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BACKGROUND OF THE INVENTION
This application is a continuation-in-part of U.S. Ser. No. 07/639,614, filed Jan. 10, 1991 now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/476,928 filed Feb. 8, 1990 now abandoned.
The present invention relates to tricyclic-cyclic amines of the formula I below, and pharmaceutically acceptable salts of such compounds. The compounds of formula I are cholinesterase inhibitors and are useful in enhancing memory in patients suffering from dementia and Alzheimer's disease.
Alzheimer's disease is associated with degeneration of cholinergic neurons in the basal forebrain that play a fundamental role in cognitive functions, including memory. Becker et al., Drug Development Research, 12, 163-195 (1988). As a result of such degeneration, patients suffering from the disease exhibit a marked reduction in acetylcholine synthesis, choline acetyltransferase activity, acetylcholinesterase activity and choline uptake.
It is known that acetylcholinesterase inhibitors are effective in enhancing cholinergic activity and useful in improving the memory of Alzheimer's patients. By inhibiting acetylcholinesterase enzyme, these compounds increase the level of the neurotransmitter acetylcholine, in the brain and thus enhance memory. Becker et al., supra, report that behavioral changes following cholinesterase inhibition appear to coincide with predicted peak levels of acetylcholine in the brain. They also discuss the efficacy of the three known acetylcholinesterase inhibitors physostigmine, metrifonate, and tetrahydroaminoacridine.
SUMMARY OF THE INVENTION
The present invention relates to compounds of the formula ##STR2## wherein P is ##STR3## Ring A is benzo, thieno, pyrido, pyrazino, pyrimido, furano, selenolo or pyrrolo;
R 2 is hydrogen, (C-C 4 )alkyl, benzyl, fluoro or cyano;
R 3 , R 4 , R 5 and R 6 are each independently selected from hydrogen, (C 1 -C 6 ) alkoxy, benzyloxy, phenoxy, hydroxy, phenyl, benzyl, halo, nitro, cyano, COOR 9 , CONHR 9 , NR 9 R 10 , NCOR 9 COR 10 , (C 1 -C 6 ) alkyl optionally substituted with from 1 to 3 fluorine atoms; SO p CH 2 -phenyl wherein p is 0, 1 or 2; pyridylmethyloxy or thienylmethyloxy; wherein the phenyl moieties of said phenoxy, benzyloxy, phenyl and benzyl groups, and the pyridyl and thienyl moieties of said pyridylmethyloxy and thienylmethyloxy may optionally be substituted with 1 or 2 substituents independently selected from halo, (C 1 -C 4 ) alkyl, trifluoromethyl, (C 1 -C 4 )alkoxy, cyano, nitro and hydroxy;
or two of R 2 , R 3 , R 4 , R 5 and R 6 are attached to adjacent carbon atoms and form, together with said adjacent carbon atoms, a saturated 5 or 6 membered ring wherein each atom of said ring is carbon, nitrogen or oxygen (e.g. a methylenedioxy or ethylenedioxy group or a lactam ring);
R 9 and R 10 are each independently selected from hydrogen and (C 1 -C 6 )alkyl, or NR 9 R 10 together form a 4 to 8 membered ring wherein one atom of the ring is nitrogen and the others are carbon, oxygen or nitrogen, or NR 9 COR 10 together form a 4 to 8 membered cyclic lactam ring;
G is carbon or nitrogen;
E is carbon, nitrogen, oxygen, sulfur, sulfoxide or sulfone;
the curved dashed line in ring B represents one double bond, so that ring B contains two double bonds, and the curved dashed line in ring D represents an optional double bond, so that ring D may contain 1 or 2 double bonds;
each of the straight dashed lines connecting, respectively, R 11 the carbon to which P is attached and X to ring D represents an optional double bond;
the carbon at any of positions 1-3 of ring D may optionally be replaced by nitrogen when such carbon is adjacent to a carbonyl group, the carbon atom of which is at position 1, 2 or 3 of ring D, so that ring D is a lactam ring;
X is O, S, NOR 1 hydrogen or (C 1 -C 6 )alkyl, with the proviso that X is double bonded to ring D only when the member of ring D to which it is bonded is carbon and X is O, S or NOR 1 ;
R 1 is hydrogen or (C 1 -C 6 )alkyl;
q is an integer from 1 to 2;
n is an integer from 1 to 3 when ring D is a lactam ring and n is an integer from 0 to 3 when ring D is not a lactam ring;
M is carbon or nitrogen;
L is phenyl, phenyl-(C 1 -C 6 )alkyl, cinnamyl, or pyridylmethyl, wherein the phenyl moieties of said phenyl and phenyl -(C 1 -C 6 )alkyl may optionally be substituted with 1-3 substituents independently selected from (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 1 -C 4 )alkoxycarbonyl, (C 1 -C 4 )alkylcarbonyl or halo;
R 11 is hydrogen, halo, hydroxy, (C 1 -C 4 ) alkyl, (C 1 -C 4 )alkoxy or oxygen;
R 12 and R 13 are each independently selected from hydrogen, fluoro, hydroxy, acetoxy, mesylate, tosylate, (C 1 -C 4 ) alkyl, and (C 1 -C 4 )alkoxy; or R 12 and R 13 may, together with the atoms to which they are attached, when both of R 12 and R 13 are attached to carbon atoms, form a three, four or five membered ring wherein each atom of said ring is carbon or oxygen.
R 7 and R 8 are each independently selected from hydrogen, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, wherein said (C 1 -C 6 )alkoxy is not attached to a carbon that is adjacent to a nitrogen; (C 1 -C 6 )alkoxycarbonyl, and (C 1 -C 6 )alkylcarbonyl;
or R 8 and R 12 , together with the atoms to which they are attached, form a saturated carbocyclic ring containing 4 to 7 carbons wherein one of said carbon atoms may optionally be replaced with oxygen, nitrogen or sulfur;
with the proviso that:
(a) when E is carbon, nitrogen, oxygen, sulfur, sulfoxide or sulfone, then G is carbon;
(b) when G is nitrogen, then E is carbon or nitrogen;
(c) when either E and G are both nitrogen, or G is carbon and E is oxygen, sulfur, sulfoxide or sulfone, then R 2 is absent;
(d) each of the atoms at positions 1, 2 and 3 of ring D may be bonded by no more than one double bond; and (e) X is attached to the position on ring D that is adjacent to the position to which the hydrocarbon substituent containing P is attached.
The present invention also relates to the pharmaceutically acceptable acid addition salts of compounds of the formula I. Examples of such pharmaceutically acceptable acid addition salts are the salts of hydrochloric acid, p-toluenesulfonic acid, fumaric acid, citric acid, succinic acid, salicylic acid, oxalic acid, hydrobromic acid, phosphoric acid, methanesulfonic acid, tartaric acid, di-p-toluoyl tartaric acid, and mandelic acid.
This invention further relates to a pharmaceutically composition for inhibiting cholinesterase comprising a compound of the formula I or a pharmaceutically acceptable acid addition salt thereof, and a pharmaceutically acceptable carrier.
The invention further relates to a method for inhibiting cholinesterase in a mammal comprising administering to a mammal an amount of a compound of the formula I or a pharmaceutically acceptable acid addition salt thereof effective in inhibiting chlolinesterase.
The invention further relates to a method for enhancing memory or treating or preventing Alzheimer's disease in a mammal comprising administering to a mammal an amount of a compound of the formula I or a pharmaceutically acceptable acid addition or salt thereof effective in enhancing memory or treating or preventing Alzheimer's disease.
The term "mammal", as used herein, includes humans.
The term "halo", as used herein, includes chloro, bromo or fluoro.
The term "(C 1 -C 4 ) alkylcarbonyl" as used herein, refers to a substituent of the formula ##STR4## wherein R 18 is (C 1 -C 4 ) alkyl.
The term "phenylcarbonyl" as used herein, refers to a substituent of the formula V above, wherein is phenyl. The term "(C 1 -C 4 ) alkoxycarbonyl" refers to a substituent of the formula V above, wherein f is (C 1 -C 4 ) alkoxy.
The term "(C 1 -C 6 ) alkoxycarbonyl" as used herein, refers to a substituent of the formula V above, wherein R 7 is (C 1 -C 6 ) alkoxy.
The term "(C 1 -C 4 )alkylcarbonyl", as used herein, refers to a substituent of the formula V above, wherein is (C 1 -C 6 )alkyl.
Preferred compounds of this invention are compounds of the formula I above, wherein E is carbon or nitrogen, G is nitrogen, ring A is benzo, pyrido or thieno, two of R 3 , R 4 R 5 and R 6 are hydrogen and the other two are independently selected from hydrogen, methyl, ethyl, propyl, methoxy, ethoxy, propyloxy, benzyloxy, hydroxy, tosyloxy, fluoro, acetoxy, N-ethylcarbamate ester and N-methylcarbamate ester; X is oxygen or sulfur and is attached to the carbon at position "1" of ring D, each of R 2 , R 11 , R 12 and R 13 is hydrogen, the hydrocarbon chain to which P is attached is single or double bonded to ring D, and P is ##STR5## Other preferred compounds of this invention are those having formula I above, wherein E is carbon, nitrogen, sulfur or oxygen, G is carbon, ring A is benzo, pyrido or thieno, two of R 3 , R 4 , R 5 and R 6 are hydrogen and the other two are independently selected from hydrogen, methyl, ethyl, propyl, methoxy, ethoxy, propyloxy, benzyloxy, acetoxy, N-methylcarbamate ester, N-methylcarbamate ester, hydroxy, tosyloxy and fluoro, X is oxygen or sulfur and attached to the carbon at position "1" of ring D, each of R 2 , R 11 , R 12 and R 13 is hydrogen, the hydrocarbon chain to which P is attached is single or double bonded to ring D, and P is ##STR6##
Specific preferred compounds of the invention are:
2,3-dihydro-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-6,7-dimethoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-7-fluoro-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-7-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-6-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-8-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-di hydro-6-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indol-1-one; 2,3-di hydro-7-benzyloxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-7-ethoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-8-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-7-p-tosyloxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-7-fluoro-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-6,7-dimethoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-9-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-7-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-6-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-8-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-6-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-6-benzyloxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-7-ethoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-8-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-7-tosyloxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-7-hydroxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-2-methyl-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-7-acetoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one;
2,3-dihydro-1-oxo-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indole-7-ol, methyl carbamate ester;
2,3-dihydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-thione;
2,3-dihydro-7-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-thione;
2,3-dihydro-7-hydroxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-thione;
1,2,3,4-tetrahydro-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-1-one;
1,2,3,4-tetrahydro-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-cyclopent[b]indol-3-one; 1,2,3,4-tetrahydro-4-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-5-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-6-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl methylene]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-8-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl methylene]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl methylene]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-4-benzoyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-6,7-dimethoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-6,7-dimethyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-4-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-5-methoxy-2-[[1-(phenylmethyl)-4 piperidinyl]methyl]-cyclopent [b]indol-3-one;
1,2,3,4-tetrahydro - 6 -methoxy- 2 -[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent [b]indo 1-3-one;
1,2,3,4-tetrahydro-8-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-4-benzyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-7-methoxy-2-[[1-(phenylmethyl)-4 -piperidinyl]methyl]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-4-benzoyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3 -one;
1,2,3,4-tetrahydro-4-tosyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3 -one;
1,2,3,4-tetrahydro-6,7-dimethoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3 -one;
1,2,3,4-tetrahydro-6-hydroxy-2-[[1-(phenylmethyl)-4 piperidinyl]methyl]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-7-hydroxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-6,7-dimethyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3-one;
1,2,3,4-tetrahydro-4-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3-thione;
1,2,3,4-tetrahydro-5-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3-thione;
1,2,3,4-tetrahydro-6-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3-thione;
1,2,3,4-tetrahydro-8-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3-thione;
1,2,3,4-tetrahydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3 -thione;
1,2,3,4-tetrahydro-6,7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3 -thione;
1,2,3,4-tetrahydro-6-hydroxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3 -thione;
1,2,3,4-tetrahydro-7-hydroxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3 -thione;
1,2,3,4-tetrahydro-6,7-dimethyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-3-thione;
2,3-dihydro-6-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-cyclopent[b](benzo [b]furan)-1-one;
2,3-dihydro-6-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-cyclopent[b](benzo [b]furan)-1-one;
2,3-dihydro-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]benzimidazol-1-one;
2,3-dihydro-6-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]]methylene]-1H-cyclopent[b](benzo [b]thieno)-1one;
6,7-dihydro-6-[[1-(phenylmethyl)-4-piperidinyl]methyl]-5H-thieno [3,2-b]-pyrrolizine-5-one;
2,3-dihydro-2 -[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a](thieno[2,3-b]pyrrol)-1-one;
2,3-dihydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a](6-azaindol )-1-one;
2,3-dihydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a](6-azaindol )-1-one;
1,2,3,4-tetrahydro-6-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]ethyl]-pyrrolo[3,4-b]indol-3-one;
1,2,3,4-tetrahydro-6-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]ethyl]-pyrrolo[3,4-b]indol-3-one;
1,2,3,4-tetrahydro-7-methyl-2-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]-pyrrolo[3,4-b]indol-3-one;
2,3-dihydro-1-hydroxy-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indole;
2,3-dihydro-1-hydroxy-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indole;
2,3-dihydro-1-acetoxy-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indole;
2,3-dihydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-oxime;
1,4-dihydro-7-chloro-2-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]pyrrolo[3,4-b]indol-3(2H)-one;
1,2-dihydro-7-methyl-2-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]pyrrolo[3,4-(benzo[b]thieno)-1H-3-one;
1,2-dihydro-6-methyl-2-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]pyrrolo[3,4-b](benzo[b]thieno) 1H-3-one;
1,2-dihydro-7-chloro-2-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]pyrrolo[3,4-b](benzo[b]thieno)1H-3-one;
2,3-dihydro-5-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-cyclopent[b](benzo[b]thieno)-1-one;
2,3-dihydro-5-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-cyclopent[b](benzo[b]thieno)-1-one;
The compounds of formula I may have optical centers and may therefore occur in different isomeric forms. The invention includes all isomers of such compounds of formula I, including mixtures thereof.
DETAILED DESCRIPTION OF THE INVENTION
The preparation of compounds having the formula I and certain of the starting materials used in their synthesis is illustrated in the following reaction schemes. In the reaction schemes and discussion that follow, the compounds of formula I are represented by the formulae I-A, I-B, I-C. . . Except where otherwise stated in the reaction schemes and discussion that follow, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , A, B, D, E, G, P, n, q, p, M, N, L, and the curved and straight dashed lines are defined as above.
All articles, books, patents and patent applications cited in the following discussion are incorporated herein by reference. ##STR7##
The novel compounds of formula I are prepared from a variety of tricyclic ketones having the formula ##STR8##
Listed below are several species of the tricyclic ketones of formula III, represented, respectively, by the formulae III-A through III-M, followed by the methods by which they may be obtained. ##STR9##
Tricyclic ketones having the formula III-A may be prepared from compounds of the formula ##STR10## by known methods described in the literature.
Compounds of the formula VI, wherein ring A is benzo may be prepared by the Fischer-Indole Synthesis (J. Chem. Soc. 7185 (1965); J. Chem. Soc., 3499 (1955); J. Chem. Soc. Trans. 59, 209 (1891); Brian Robinson, The Fischer Indole Synthesis (1982)) and by the Reissert Synthesis (Heterocyclic Compounds, 3, 18 (1962); J. Am. Chem. Soc., 71, 761 (1949)). Compounds of the formula VI, wherein ring A is pyrido, pyrazino or pyrimido, may be prepared by a method analogous to the Reissert Synthesis (J. Med. Chem., 2, 1272 (1989); J. Am. Chem. Soc., 87, 3530 (1965)). Compounds of the formula VI, wherein ring A is benzo, thieno, furano, selenolo or pyrrolo, may be prepared as described in Collect. Czech. Chem. Commun., 46, 2564 (1981), (Can. J. Chem., 56, 1429 (1978) and J. Chem. Soc. Perkin Trans. I, 931 (1987).
The tricyclic ketones of the formula III-A may be synthesized from the corresponding compounds of the formula VI, according to a procedure analogous to that described in J. Med. Chem., 28, 921 (1985). Those compounds of the formula III-A wherein R 2 is other than hydrogen may also be synthesized from the corresponding compounds of the formula VI, according to a procedure analogous to that described in Arch. Pharm., 308, 779 (1975).
Tricyclic ketones of the formula III-B wherein ring A is benzo may be prepared from the corresponding compounds having the formula ##STR11## using the Fischer-Indole Synthesis, as described in Heterocycles, 12, 913 (1979), Khim-Farm Zh, USSR, 23, 229 (1989), J. Org. Chem., USSR (English), 1586 (1966) and Japanese Patent 56083471. Compounds of the formula III-B, wherein ring A is benzo, thieno, pyrido, pyrazino, pyrimido, furano, selenolo or pyrrolo may be prepared from the corresponding compounds having the formula ##STR12## by a method analogous to that described in J. Med. Chem., 32, 1098 (1989). Alternatively, they may prepared starting with corresponding compounds of the formula ##STR13## by a procedure analogous to that described in Bull. Chem. Soc. Japan, 49, 737 (1976) and Am. Chem., 662, 147 (1963).
Tricyclic ketones having the formula III-C, may be prepared according to the methods described in J. Org. Chem., 42, 1213 (1977), J. Heterocyclic Chem. 24, 1321, (1987); J. Chem. Soc., 700 (1951), Ann. Chem., 696, 116 (1966), and J. Org. Chem., 45, 2938 (1980). Tricyclic ketones having the formula III-D, may be obtained as follows. First, a compound having the formula ##STR14## is synthesized from the corresponding compound of the formula ##STR15## by a procedure analogous to that described in J. Chem. Soc., C 1, 70 (1969). The alcohol product is then oxidized to form the desired tricyclic ketone. The oxidation reaction is generally performed using manganese dioxide or selenium dioxide in a solvent such as methylene chloride, benzene, chloroform, toluene, dioxane or tetrahydrofuran (THF) at a temperature from about room temperature to about the reflux temperature of the solvent.
Tricyclic ketones having the formula III-E may be prepared from the corresponding compounds having the formula ##STR16## by a method analogous to that described in J. Chem. Soc., 863 (1951) and J. Org. Chem., 29, 175 (1964).
Tricyclic ketones of the formulae III-F and III-G may be prepared from the corresponding compounds of the formula ##STR17## according to a procedure analogous to that described in Bull. Chem. Soc., Japan, 49, 737 (1976), Ann. Chem., 662, 147 (1963) and J. Heterocyclic Chem., 7, 107 (1970).
Tricyclic ketones having the formula III-H may be prepared from the corresponding tricyclic ketones of the formula III-G as illustrated in scheme 7. The appropriate compound of the formula III-G is reacted with one equivalent of a peracid such as m-chloroperbenzoic acid or peracetic acid, in a suitable reaction inert solvent such as chloroform or methylene chloride, at a temperature from about 0° to about 70° C., to yield the desired product of formula III-H. Alternatively, the appropriate compound of the formula III-G can be reacted with sodium periodate in a water/alcohol solvent such as water/methanol or water/ethanol at a temperature from about 0° to about 70° C.
The preparation of tricyclic ketones having the formula III-J is also illustrated in scheme 7. These compounds may be obtained starting with the corresponding compounds of the formula III-G or those of the formula III-H. The first method involves reacting the appropriate compound of the formula III-G with potassium permanganate in a suitable reaction inert solvent such as acetone/water, at a temperature from about 0° to about 50° C. Alternatively, the appropriate compound of the formula III-G may be reacted with greater than two equivalents of m-chloroperbenzoic acid or peracetic acid in a suitable reaction inert solvent such as chloroform or methylene chloride, at a temperature from about 0° to about 60° C. Such appropriate compound of the formula III-G may also, alternatively, be reacted with hydrogen peroxide in a water/alcohol solvent such as water/methanol or water/ethanol, at a temperature from about 0° to about 50° C. All three of the foregoing reactions yield tricyclic ketones of the formula III-H.
As mentioned above, tricyclic ketones of the formula III-J may also be prepared from the corresponding compounds of the formula III-H. Such compounds of the formula III-H will yield the desired tricyclic ketones of the formula III-H when reacted with either a peracid or hydrogen peroxide. Each of these reactions is typically carried out as described in the preceding paragraph.
Tricyclic ketones of the formula III-K may be prepared by a procedure analogous to those described in Ann. Chem., 1437 (1985), Ann. Chem., 1422 (1985); Ann. Chem., 239 (1989); Zimmer, H., Natural Product Gordon Research Conference, New Hampton School (July, 1989).
Tricyclic ketones of the formulae III-L and III-M may be prepared by a method analogous to that described in European Patent Application EP 317088.
Scheme 8 illustrates how tricyclic ketone intermediates containing a carbonyl group at position "2" of ring D (i.e., wherein an oxygen is double bonded to the carbon at position "2") may be obtained from the corresponding tricyclic ketones wherein the carbonyl group is at position "1" or "3" of ring D. This procedure is analogous to that described in Can. J. Chem., 60, 2678 (1982).
The novel compounds of formula I are prepared from tricyclic ketones of the formula III as illustrated in Schemes 1-6 and described below.
Referring to scheme 1, compounds of the formula I-A may be prepared by reacting a tricyclic ketone of the formula III with an aldehyde of the formula ##STR18## This reaction is generally carried out in a suitable reaction inert solvent in the presence of a base. Sodium hydride, piperidine or pyrrolidine may be used as the base, and the reaction conducted in a solvent such as tetrahydrofuran (THF), dimethylformamide (DMF), dioxane or toluene, with or without ethanol, at a temperature from about -40° to about 110° C. Alternatively, lithium or sodium diisopropylamide or lithium or sodium bis(trimethylsilyl)amide may be used as the base. When using such alternative method, the base is typically first added to the compound of formula III in a solvent such as THF, methylene chloride or toluene, preferably THF, at a temperature from about -° 78 to about 0° C., followed by addition of the aldehyde. After addition of the aldehyde, the reaction mixture is stirred at a temperature from about -78° to about 40° C., preferably from about 0° C. to about room temperature. In a second alternative method, a sodium or potassium (C 1 -C 4 ) alkoxide may be used as the base, and the reaction conducted in a reaction inert solvent such as toluene, DMF, THF or methylene chloride, with or without ethanol (1 to 3 equivalents to base), or in a lower alcohol, at a temperature from about -40° C. to about the reflux temperature of the solvent preferably from about 0° C. to about room temperature.
Preferably, the foregoing reaction of the tricyclic ketone and aldehyde is carried out using sodium hydride, piperidine, pyrrolidine or lithium diisopropyl amide as the base and THF or toluene as the solvent, at a temperature from about 0° C. to about 110° C. The foregoing reaction, using any of the three above methods, may be quenched with 1-3 equivalents of acetyl chloride, mesyl chloride or tosyl chloride, to give the desired compound of formula I-A.
Compounds of the formula I-B may be prepared by hydrogenating the corresponding compound of formula I-A. The hydrogenation is usually carried out using platinum dioxide or palladium on charcoal, in a suitable reaction inert solvent, at a temperature from about 15° to about 70° C. and a pressure from about 0. 5 to 6 atm. Examples of suitable solvents are lower alcohols, ethyl acetate and THF, with or without ethanol. The preferred solvent is a mixture of ethanol and THF or a mixture of ethanol and ethyl acetate, and the preferred temperature is about room temperature.
Formula IC, also shown in scheme 1, represents compounds wherein P is ##STR19## Compounds of the formula IC may be obtained, as illustrated in scheme 1, from tricyclic ketones of the formula III by reacting said tricyclic ketone with formaldehyde or a formaldehyde polymer and a compound of the formula ##STR20## Generally, this reaction is conducted in a suitable reaction inert solvent such as a lower alcohol/water mixture or THF, and at a temperature from about 10° C. to about 200° C. Preferably, the solvent is alcohol/water, the temperature is from about room temperature to about 100° C. and the pH of the reaction mixture is from about 2.5 to about 3.5.
Compounds of the formula I-B or I-C may be converted to the corresponding compounds of the formula I-D, I-E and I-F, by the procedure illustrated in scheme 2. Compounds of the formula I-B may be converted to the corresponding compounds of the formula I-D by the following two methods. The first method involves brominating a compound of the formula IB or IC and then subjecting the resulting brominated compound to an elimination reaction. The bromination step is typically carried out by reacting the compound of formula I-B with a brominating agent such as liquid bromine, pyridinium bromide perbromide or N-bromosuccinimide, in the presence of a catalytic amount of benzoyl peroxide, in a suitable reaction inert solvent. Examples of suitable solvents are carbon tetrachloride, methylene chloride and THF. Carbon tetrachloride is preferred. Reaction temperatures may range from about 0° to about 80° C. , with about 80° C. being preferred. The elimination reaction is typically carried out by reacting the resulting brominated compound from the previous step with a base such as diazabicycloundecane (DBU) or diazabicyclononane (DBN). Suitable solvents for this reaction include THF, methylene chloride, and chloroform, with methylene chloride being preferred. Suitable temperatures range from about 0° to about 100° C., with about 70° C. being preferred.
The second method involves adding selenium to a compound of the formula I-B and then subjecting the resulting selenium derivative to an elimination reaction. The selenium addition is typically carried out by reacting a compound of the formula I-B with a selenium agent such as phenylselenium chloride, ##STR21## in a suitable reaction inert solvent in the presence of a base. Examples of bases that may be used are sodium hydride, lithium diisopropylamide or sodium or potassium (C 1 -C 4 ) alkoxides. Examples of suitable solvents are THF, methylene chloride and toluene. THF is preferred. The reaction may be conducted at temperatures from about -78° C. to about room temperature. The elimination reaction is typically carried out by reacting the resulting selenium derivative from the previous step with an oxidizing agent such as sodium periodate. Suitable solvents for this reaction include water/lower alcohol mixtures, dioxane and THF, with ethanol/water being preferred. Reaction temperatures may range from about 0° to about 150° C. Temperatures from about 0° C. to about room temperature are preferred.
The R 11 substituent may be added to ring D of the compounds of formula I as illustrated by the conversion of compounds of the formula I-D to the corresponding compounds of the formula I-E, shown in scheme 2. This is accomplished by reacting the appropriate compound of the formula I-D with a compound of the formula (R)2 CuLi, in a suitable reaction solvent, at a temperature from about -78 to about 50° C. Examples of suitable solvents include THF, methylene chloride, dioxane, and ether. THF is the preferred solvent. The reaction may optionally be conducted in the presence of a compound having the formula (R 15 ) 3 SiCl, wherein R 15 is methyl or ethyl.
The R 12 substituent may be added to ring D of the compounds of the formula I, as illustrated by the conversion of compounds of the formula I-E to compounds of the formula I-F, also shown in scheme 2. This is accomplished by reacting the appropriate compound of the formula I-D with a base in a suitable reaction insert solvent, and then adding a compound of the formula R 16 X, wherein X is a leaving group, to the reaction mixture. Generally, this reaction is conducted at a temperature from about -78 to about 40° C., and preferably from about 0° C. to about room temperature. Bases that may be used include sodium hydride, lithium diisopropylamide, triethylamine, and sodium and potassium (C 1 -C 4 ) alkoxides. The preferred bases are lithium diisopropylamide and sodium hydride. Suitable solvents include THF, methylene chloride, toluene, ether and DMF. The preferred solvent is THF. Suitable leaving groups include iodine, bromine, rosylate and mesylate.
Compounds of the formula I that are identical, respectively, to those of formulae I-D, I-E and I-F, except that the carbonyl group is at position "2" or position "3" of ring D rather than position "1" of ring D, may be prepared by the methods described above and illustrated in scheme 2, substituting the starting compounds of, respectively, formulae I-C, I-D and I-E with the corresponding compounds wherein the carbonyl group is at position "3" of ring D.
Scheme 3 illustrates the preparation of the novel compounds of the invention having the formulae I-G and I-H from compounds of the formula I-A. The conversion of compounds of the formula I-A to the corresponding compounds of the formula I-G illustrates the addition of the R 13 substituent to ring D. This is accomplished by reacting the appropriate compound of the formula I-A with a compound of the formula (R 13 ) 2 CuLi, in a suitable solvent at a temperature from about -78° to about 40° C. Examples of suitable solvents include THF, methylene chloride, dioxane and ether. THF is the preferred solvent. The reaction may optionally be conducted in the presence of a compound having the formula (R 15 ) 3 SiCl, wherein R 15 is methyl or ethyl.
Compounds of the formula I-H may be prepared from the corresponding compounds of the formula I-G by addition of the R 12 substituent to the carbon at position "2" of ring D, according to the method described above from preparing compounds of the formula I-E from the corresponding compounds of the formula I-D.
Compounds identical to those of formulae I-G and I-H, except that the carbonyl group is at position "3" of ring D, may be prepared from the corresponding compounds identical to compounds of formulae I-A and I-G, except that the carbonyl group is at position "2" or position "3" of ring D, respectively, according to the methods described above for preparing compounds of the formulae I-G and I-H.
Scheme 4 illustrates a method of synthesizing of compounds of the formulae I-K and I-L from the corresponding compounds of the formula I-A. To obtain compounds of the formula I-K, the corresponding compounds of the formula I-A are reacted with an epoxidizing agent. An example of a suitable epoxidizing agent is sodium hydroxide/hydrogen peroxide. This reaction is usually conducted in a reaction inert solvent such as a mixture of water and a lower alcohol, preferably water/ethanol. The reaction temperature may range from about -20° to about 70° C., with about room temperature being preferred.
Compounds of the formula I-L may be obtained from the corresponding compounds of the formula I-A, via a Simmons-Smith reaction (See J. Org. Chem., 54, 5994 (1989) and J. Org. Chem., 52, 3943 (1987). This reaction is carried out by reacting a derivative of the formula I-A with methylene iodide/zinc copper amalgam. Typically, this reaction is carried out at a temperature from about 0° to about 150° C., preferably from about 0° C. to about room temperature. Suitable solvents include ether, dimethoxyethane and THF. Dimethoxyethane is the preferred solvent.
Compounds of the formula I-M may be obtained as illustrated in scheme 5. First, a tricyclic ketone of the formula III is reacted with a (C 1 -C 4 )alkyl silyl chloride or a Lewis acid, in the presence of a base. Examples of appropriate Lewis acids are (R 17 ) 2 AlCl or (R 17 ) 2 BCl, wherein R 17 is (C 1 -C 4 ) alkyl or cyclohexyl. Appropriate bases include triethylamine and diisopropylethylamine. The reaction is generally conducted at a temperature from about -78° C. to about 50° C., preferably form about -78° C. to about room temperature. Suitable solvents include THF, methylene chloride, toluene, ether or dioxane. The preferred solvent is THF Then, a compound of the formula ##STR22## is added to the reaction mixture, with or titanium tetrachloride.
Derivatives of compounds of the formula I-M, wherein the hydroxy group is replaced by either acetate, mesylate, tosylate or fluoro, may be prepared as follows. To obtain an acetate derivative, the corresponding compound of the formula I-M is reacted with acetic anhydride or acetyl chloride. This reaction is generally conducted in the presence of a base such as triethylamine, diisopropylethylamine or pyridine, and at a temperature from about 0° to about 60° C., preferably from about 10° to about 30° C. Suitable solvents include methylene chloride, chloroform and THF, with methylenechloride being preferred. The mesylate and tosylate derivatives may be obtained using the same method and substituting respectively, mesyl chloride or tosyl chloride for acetic anhydride or acetyl chloride.
Fluoro derivatives may be prepared by reacting the corresponding compound of the formula I-M with diethylaminosulfonium trifluoride. Typically this reaction is carried out at a temperature from about -78° C. to about room temperature, in an appropriate reaction inert solvent such as methylene chloride, THF or ether. The preferred temperature is from about -78° to 0° C. and the preferred solvent is THF.
Compounds identical to those having the formula IA or IB except that the carbonyl group in ring D is replaced by C═NOR 1 may be prepared by reacting the corresponding compounds of formula I-A or I-B with a compound of the formula H 2 NOR 1 HCl in a suitable reaction inert solvent and in the presence of a base. Suitable solvents include water/lower alcohols, methylene chloride and chloroform, with ethanol/water being preferred. Suitable bases include sodium acetate, pyridine or triethylamine. The reaction may be conducted at a temperature from about 0° to about 150° C. From about 30° to about 70° C. is preferred.
Scheme 6 illustrates a method of synthesizing compounds having the formulae I-O, I-P and I-Q from the corresponding compounds of the formula I-B. Compounds of the formula I-O may be prepared by reacting the corresponding compounds of the formula I-B with a reducing agent. Suitable reducing agents include sodium borohydride and lithium aluminum hydride. Solvents appropriate for use with sodium borohydride include lower alcohols, with methanol or ethanol being preferred. Solvents appropriate for use with lithium aluminum hydride include THF, ether and dioxane, with THF being preferred. Generally, this reaction is conducted at temperatures from about room temperature to 100° C. The preferred temperature is 30° C.
The compounds of the formula I-O prepared by the foregoing procedure may be converted to the corresponding compounds of the formula I-P, wherein ring D contains a double bond between the carbons at positions "1" and "2" or between the carbons at positions "2" and "3" by first converting them to the corresponding acetate, mesylate or tosylate derivatives wherein the acetate, mesylate or tosylate group replaces the hydroxy group, according to the procedures described above for converting compounds of the formula I-M to, respectively, the acetate, mesylate or tosylate derivatives thereof, and then subjecting the derivatives formed thereby to an elimination reaction. The elimination reaction is typically carried out using a base such as diazabicycloundecane or diazabicyclononane in a suitable reaction inert solvent, at a temperature from about 0° to about 100° C., preferably from about 0° to about 100° C. Suitable solvents include methylene chloride, chloroform and THF. Methylene chloride is preferred.
Compounds of the formula I-Q, wherein ring D contains a double bond between the carbons at positions "1" and "2" or between the carbons at positions "2" and "3" and wherein R 11 and the hydrocarbon chain containing P are attached to adjacent carbons of ring D connected by a double bond, may be prepared from the corresponding compounds of the formula I-B. This is accomplished by reacting the appropriate compound of the formula I-B with a compound of the formula R 11 MgX, wherein X is chloro, bromo, or iodo, in a suitable reaction inert solvent, and then adding, successively, a dilute acid such as dilute hydrochloric acid, dilute sulfuric acid or dilute phosphoric acid, and a base such as a saturated solution of sodium bicarbonate or sodium hydroxide. Generally, this reaction is conducted at temperatures from about -78° to about 100° C., preferably from about 0° C. to about room temperature for the addition of R 11 MgX, and at about room temperature for the addition of the acid. Examples of suitable solvents for the reaction with R 11 MgX are THF, ether and toluene.
Scheme 9 illustrates the preparation of compounds having the formula I-R. These are compounds of the formula I wherein the carbon at position 2 of ring D is replaced nitrogen, an oxo group (═O) is attached to the carbon at position 1 of the same ring, q is 2 and M is carbon.
Compounds of the formula I-R may be prepared by first subjecting the appropriate compound of the formula VII to reductive amination using a compound of the formula ##STR23## and a reducing agent such as sodium cyanoborohydride, sodium triacetoxyborohydride or sodium borohydride. The reductive amination is carried out in a suitable reaction inert solvent such as acetic acid, a lower alcohol, THF or mixtures containing a lower alcohol and THF, at a temperature from about 0° C. to about 60° C. Preferably, it is carried out at about room temperature in acetic acid or a THF/lower alcohol mixture.
The foregoing reaction yields a compounds of the formula VIII. Acid or base hydrolysis of this compound followed by amide formation yields the corresponding compound of formula I-R. When R is (C 1 -C 8 ) alkyl, compound of the formula VIII are hydrolyzed by base hydrolysis. Examples of bases that may be used include lithium and sodium hydroxide (lithium hydroxide is preferred). Suitable solvents include dioxane/water, ether/water, THF/water, and (C 1 -C 5 ) alkanol/water. Dioxane/water is preferred. When R is benzyl, compounds of the formula VIII are hydrolyzed under acidic conditions using, for example, aqueous hydrogen bromide in acetic acid. Alternatively, such compounds (e. g., wherein R is benzyl) may be hydrogenated using palladium on carbon in a (C 1 -C 4 ) alkanol to yield the corresponding compounds of formula IX. The hydrolysis reaction is generally run at a temperature from about 20° C. to about 120° C., preferably at about 25° C.
Compounds of the formula IR may be prepared by subjecting the corresponding compounds of formula IX to lactam formation conditions. The reagent typically used for the lactam formation is a dialkylcarbodiimide such as N-ethyl-N'-[2-(dimethylamino)ethyl]carbodiimide (EDEC), N-ethyl-N'-[2-(dimethylamino)propyl]carbodiimide (EDPC), 1-cyclohexyl-3-(2-morpholinoethyl)carbodiimide metho-p-toluenesulfonate (CMCMT) or dicyclohexylcarbodiimide. EDEC or CMCMT is preferred. This reaction is usually carried out in an aprotic solvent such as DMF or pyridine in the presence of a base at a temperature from about 10° C. to about 60° C., preferably at about room temperature.
Alternatively, the lactam formation step may be carried out using titanium IV isoproxide in dichloroethane at a temperature from about 20° C. to about 100° C., preferably from about 60° C. to about 85° C.
It is preferable to prepare certain of the compounds of the formula I by "the following methods rather than those described above due to the nature of the R 3 to R 6 substituents.
When one of the R 3 to R 6 substituents is CONHR 9 , the final product of formula I may be prepared from the corresponding compound of the formula I wherein such substituent is COOR 9 by acid or base hydrolysis, followed by reaction with thionyl chloride and a compound of the formula R 9 NH 2 . The acid hydrolysis is generally carried out using 2N-6N hydrochloric acid and the base hydrolysis is generally carried out using lithium, potassium or sodium hydroxide in water or a lower alcohol/water solvent. Temperatures for both the acid and base hydrolysis generally range from about room temperature to about 100° C. About 100° C. is preferred. The reaction with thionyl chloride, which yields the corresponding acyl chloride, is typically carried out in a reaction inert solvent such as methylene chloride, THF or chloroform, at a temperature from about 80° to about 120° C., preferably at about 100° C. The reaction of the acyl chloride with RgNH is typically carried out in a reaction inert solvent such as methylene chloride, THF or chloroform, preferably methylene chloride, at a temperature from about room temperature to about 150° C. preferably from about 30° to about 80° C.
When one of the R 3 to R 6 substituents is NR 9 R 10 , the final product of formula I may be prepared by reduction of the corresponding compound of the formula I wherein such substituent is nitro, to first produce the corresponding compound wherein such substituent is R 9 NH, followed by reductive amination. This process may be carried out as follows. First, the nitro compound is hydrogenated or reacted with a metal and an acid to yield the corresponding amine. The hydrogenation is typically carried out using hydrogen and a catalyst such as palladium on charcoal, at a temperature from about 0 to about 100° C., preferably at about room temperature, and at a pressure from about 1 to about 6 atm, preferably about 3 atm. The reduction using a metal and an acid is generally carried out using a metal such as iron or zinc, and an acid such as concentrated hydrochloric acid. Suitable temperatures for this reaction range from about 0° to about 150° C. Temperatures from about 80° to about 120° C. are preferred.
After the reduction via hydrogenation or reaction with a metal and an acid, a compound of the formula ##STR24## is added to the resulting amine, followed by either lithium aluminum hydride, diborane dimethyl- sulfide or diborane. Examples of suitable solvents for the addition of lithium aluminum hydride are THF, ether, and dioxane. THF is preferred. Suitable solvents for the addition of diborane dimethylsulfide or diborane include THF and ether. THF is preferred. The reaction with lithium aluminum hydride, diborane dimethylfulfide, or diborane is typically carried out at temperatures from about room temperature to about 100° C., preferably from about 60° to about 80° C.
Alternatively, compound of the formula ##STR25## may be added to the resulting amine in an appropriate solvent and in the presence of a base, at a temperature from about 0°to about 100° C., preferably from about 10° to about 40° C. This reaction is followed by reduction with sodium cyanoborohydride or sodium borohydride to give the corresponding compound of the formula CONHR 9 . Sodium cyanoborohydride is preferred. Lower alcohols and acetic acid are examples of suitable solvents.
The reactions with ##STR26## lithium aluminum hydride (or diborane dimethylsulfide or diborane) or ##STR27## are the repeated in the manner described above, but replacing ##STR28## to give the final product of formula I, wherein one of R 3 to R 6 is CONR 9 R 10 .
When one of R 3 to R 6 is a hydroxy group, the final product having formula I may be prepared via base hydroysis of the corresponding compound of formula I wherein such substituent is rosylate. The base hydrolysis is typically performed using a base such as sodium or potassium hydroxide or a sodium alkoxide, in a suitable reaction inert solvent such as a mixture of a lower alcohol and water or a lower alcohol alone, at a temperature from about room temperature to about 120° C., preferably about 80°to about 100° C. The reaction mixture is then neutralized using a dilute acid such as hydrochloric acid or phosphoric acid.
In each of the above reactions, pressure is not critical. Pressures in the range of about 0.5 atm to 3 atm are suitable, and ambient pressure (generally, about one atmosphere) is preferred as a matter of convenience. Also, for those reactions where the preferred temperature varies with the particular compounds reacted, no preferred temperature is stated. For such reactions, preferred temperatures for particular reactants may be determined by monitoring the reaction using thin layer chromatography.
The compounds of the invention may be administered to a patient by various methods, for example, orally as capsules or tablets, parentally as a sterile solution or suspension, and in some cases, intravenously in the form of a solution. The free base compounds of the invention may be formulated and administered in the form of their pharmaceutically acceptable acid addition salts.
The daily dose of the compounds of the invention is generally in the range of from about 1 to 300 mg/day for the average adult human, and may be administered in single or divided doses.
When incorporated for parenteral administration into a solution or suspension, the compounds of the invention are present in a concentration of at least 1 weight percent, and preferably between about 4-70 weight percent (based on the total weight of the unit). The parenteral dosage unit typically contains between about 5 to 100 mg of active compound(s).
Compounds of the present invention may be administered orally with an inert diluent or an edible carrier, or they may be enclosed in gelatin capsules or compressed into tablets. Such preparations should contain at least 0.5% of active compound(s), but the concentration may vary depending upon the particular form and may be from 4 to 70 weight percent (based on the total weight of the unit). The oral dosage unit typically contains between 1.0 mg to 300 mg of active compound.
The activity of the compounds of the present invention as cholinesterase inhibitors may be determined by a number of standard biological or pharmacological tests. One such procedure for determining cholinesterase inhibition is described by Ellman et al. in "A New and Rapid Colorimetric Determination of Acetylcholinesterase Activity", Biochem. Pharm. 1, 88, (1961).
The present invention is illustrated by the following examples. It will be understood, however, that the invention is not limited to the specific details of these examples. Melting points are uncorrected. Proton nuclear magnetic resonance spectra ( 1 H NMR) and C 13 nuclear magnetic resonance spectra (C 13 NMR) were measured for solutions in deuterochloroform (CDCl 3 ) and peak positions are expressed in parts per million (ppm) downfield from tetramethylsilane (TMS). The peak shapes are denoted as follows: s, singlet; d, doublet; t, triplet; q, quartet; m, multiplet; b, broad.
EXAMPLE 1
Ethyl-1-benzyleridine-4-carboxylate
A mixture of ethyl isonipecotate (69.25 g, 0.441 mol). -bromotoluene (75.44 g, 52.4 ml, 0.441 mol) and triethylamine (44.74 g, 61.5 ml, 0.441 mol) in 1000 ml methylene chloride was stirred at r.t. for 20 hr. The mixture was washed with brine and the organic layer was separated, dried and concentrated to give 97.016 g of ethyl 1-benzylpiperidine-4-carboxylate as a yellow oil. HNMR (CDCl)δ 1.2(t, 3H), 1.6-1.9 (m, 4H), 2.0 (dt, 2H), 2.2-2.3 (m, 1H), 2.85 (m, 2H), 3.5 (s, 2H), 4.1 (q, 2H), 7.2-7.36 (m, 5H) ppm.
EXAMPLE 2
1-benzypiperidine-4-carboxaldehyde
To a solution of ethyl 1-benzylpiperidine-4-carboxylate (9.2 g, 0.037 mol) in 400 ml of toluene was added 1.5M diisobutylaluminum hydride in toluene (28 ml, 0. 042 mol) at -78° C. The mixture was stirred at -78° C. for 1 hr and quenched with 150 ml of MeOH and the dry ice bath was removed. After stirring for 2 hr at r.t., the mixture was filtered through diatomaceous earth (Celite (trademark)) and washed with methanol. The filtrate was concentrated to dryness to give 6.91 g (92%) of 1-benzylpiperidine-4-carboxaldehyde which can be used directly or purified by vacuum distillation, bp 93°-97° C./1 mmHg. HNMR (CDCl 3 )δ 1.6-1.8 (m, 2H), 1.8-1.9 (m, 2H), 2.05-2.17 (m, 2H), 2.17-2.3 (m, 1H), 2.75-2.9 (m, 2H), 3.5 (s, 2H), 7.2-7.4 (m, 5H), 9.6 (s, 1H) ppm.
EXAMPLE 3
2,3-dihydro-1-oxo-1H-pyrrolo[1.2-a]indole
A stirred solution of ethyl indole-2-carboxylate (5.67 g, 30 mmol) in 400 ml of toluene under N was treated with sodium hydride (1.44 g, 36 mmol). Ethyl acrylate (3.6 ml, 33 mol) was added and the mixture was heated at reflux. Additional portions of ethyl acrylate (6 mmol) and sodium hydride (16 mmol) were added after 3 hr. After a total time of 6 hr, t.l.c. indicated that all starting material are consumed. The mixture was quenched with ethanol and treated with water, dilute HCl, and methylene chloride. The organic phase was washed with brine, dried over sodium sulfate, filtered, and concentrated to give 2,3-dihydro-1-oxo-2-ethoxycarbonyl-1H-pyrrolo[1,2-a]indole, which was used directly in the next step.
A solution of 2,3-dihydro-1-oxo-2-ethoxycarbonyl-1H-pyrrolo[1,2-a]indole in 400 mL of acetic acid and 25 mL of water was heated at reflux under N 2 for 16 hr. The resulting solution was cooled and concentrated to dryness. The residue was treated with water and methylene chloride. The organic layer was washed with NaHCO 3 , brine, dried and concentrated to give solid which was purified by column chromatography to give the title compound. HNMR (CDCl 3 )δ 2.17 (t, 2H), 4.38 (t, 2H), 6.95 (s, 1H), 7.06-7.2 (m, 1H), 7.2-7.4 (m, 2H), 7.7 (d, 1H) ppm.
EXAMPLE 4
2,3-dihydro-1-oxo-7-methoxy-1H-pyrrolo[1,2-a]indole
A stirred solution of ethyl 5-methoxy-indole-2-carboxylate (30 g, 137 mmol) in 1.5 L of toluene under N 2 was treated with sodium hydride (6.7 g of 60% in oil, 167 mmol) and ethylacrylate (16.3 ml, 150 mmol). The mixture was heated to reflux. After 3 hours (hr), additional ethyl acrylate (3 ml) and sodium hydride (3.3 g) were added. After a total of 8 hr, the starting material was consumed completely and the mixture was quenched with ethanol and treated with water and dilute HCl and methylene chloride. The organic layer was washed with brine, dried and concentrated to give 2,3-dihydro-1-oxo-7-methoxy-2-ethoxycarbonyl-1H-pyrrolo[1,2-a]indole, which was used directly in the next step.
A solution of the compound produced in the previous step in 2.0 L of acetic acid and 100 ml of water was heated at reflux under N 2 for 20 hr. The reaction mixture was cooled to r.t. and concentrated. The residue was treated with water and extracted with methylene chloride. The organic layer was washed with saturated sodium bicarbonate, brine, dried and concentrated to give brown solid. The brown solid was purified through silica gel to give the title compound. 1HNMR (CDCl 3 )δ 3.15 (t, 2H), 3.8 (s, 3H), 4.4 (t, 2H), 6.9 (s, 1H), 6.96-7.1 (m, 2H), 7.2-7.3 (m, 1H) ppm.
The title compounds of Examples 5-14 were prepared using a method analogous to that described in Examples 3 and 4, starting from the corresponding substituted ethyl indole-2-carboxylate:
EXAMPLE 5
2,3-dihydro-1-oxo-6,7-dimethoxy-1H-pyrrolo[1,2a]indole was prepared starting from ethyl 5,6-dimethoxy-indole-2 -carboxylate. HNMR (CDCl 3 )δ 3.2 (t, 2H), 3.9 (s, 3H), 4.0 (s, 3H), 4.4 (t, 2H), 6.75 (s, 1H), 6.9 (s, 1H), 7.1 (s, 1H) ppm.
EXAMPLE 6
2,3-dihydro-1-oxo-7-fluoro-1H-pyrrolo[2a]indole was prepared starting from ethyl 5-fluoro-indole-2- carboxylate. 1HNMR (CDCl 3 )δ 3.25 (t, 2H), 4.4 (t, 2H), 6.9 (s, 1H), 7.1-7.2 (m, 1H), 7.2-7.5 (m, 2H) ppm.
EXAMPLE 6
2,3-dihydro-1-oxo-7-methyl-1H-pyrrolo[1,2-a]indole was prepared starting from ethyl 5-methyl-indole-2-carboxyate. HNMR (CDCl 3 )δ 2.46 (s, 3H), 3.2 (t, 2H), 4.4 (t, 2H), 6.9 (s, 1H), 7.1-7.4 (m, 2H), 7.5 (s, 1H) ppm.
EXAMPLE 8
L-dihydro-1-oxo-6-methyl-1H-pyrrolo[a]indole was prepared starting from ethyl 6-methyl-indole-2-carboxylate. 1HNMR (CDCl 3 )δ 2.48 (s, 3H), 3.2 (t, 2H), 4.4 (t, 2H), 6.96 (s, 1H), 7.0 (d, 1H), 7.2 (s, 1H), 7.65 (d, 1H) ppm.
EXAMPLE 9
2,3-dihydro-1-oxo-6-methoxy-1H-pyrrolo[1,2-a]indole was prepared starting from ethyl 6-methoxy-indole-2-carboxylate. HNMR (CDCl)δ 3.2 (t, 2H), 3.9 (s, 3H), 4.4 (t, 2H), 6.75 (d, 1H), 6.85 (dd, 1H), 6.5 (s, 1H), 7.6 (d, 2H) ppm.
EXAMPLE 10
23-dihydro-1-oxo-7-ethoxy-1H-pyrrolo[2-a]indole was prepared starting from ethyl 5-ethoxy-indole-2-carboxylate. HNMR (CDCl 3 )δ 1.4 (t, 3H), 3.17 (t, 2H), 4.0 (q, 2H), 4.4 (t, 2H), 6.85 (s, 1H), 6.9-7.1 (m, 2H), 7.28 (d, 1H) ppm.
EXAMPLE 11
2,3-dihydro-1-oxo-7-benzyloxy-1H-pyrrolo[1,2a]indole was prepared starting from ethyl 5-benzyloxy-indole-2-carboxylate. 1 HNMR (CDCl 3 )δ 3.2 (t, 2H), 4.4 (t, 2H), 5.1 (s, 2H), 6.9 (s, 1H), 7.1-7.6 (m, 8H) ppm.
EXAMPLE 12
2,3-dihydro-1-oxo-8-methyl-1H-pyrrolol[1,2-a]indole was prepared starting from ethyl 4-methyl-indole-2-carboxylate. 1 HNMR (CDCl 3 )δ 2.54 (s, 3H). 3.16 (t, 2H), 4.18 (t, 2H), 6.9 (t, 1H), 6.98 (s, 1H), 7.2 (m, 1H) ppm.
EXAMPLE 13
2,3-dihydro-1-oxo-8-methoxy-1H-pyrrolo[1,2-a]indole was prepared starting from ethyl 4-methoxy-indole-2-carboxylate. 1 HNMR (CDCl 3 )δ 3.2 (t 2H), 3.95 (s, 1H), 4.4 (t, 2H), 6.5 (d, 1H), 7.0 (d, 1H), 7.3 (m, 2H) ppm.
EXAMPLE 14
2,3-dihydro-1-oxo-7-p-tosyloxy-1H-pyrrolo[1,2-a]indole was prepared starting from ethyl 5-p-tosyloxy-indole-2-carboxylate. 1 HNMR (CDCl 3 )δ 2.4 (s, 3H), 3.2 (t, 2H), 4.4 (t, 2H), 6.9 (s, 1H), 7.0 (dd, 1H), 7.2-8.4 (m, 4H), 7.67 (d, 2H) ppm.
EXAMPLE 15
1-benzyl-4-[2,3-dihydro-1-oxo-1H-pyrrolo[1,2a]indolo)-2ylidenyl]methylpiperidine:
To a solution of the title compound of Example 3 (1.71 g, 10 mmol) in 50 ml of anhydrous THF, was added sodium hydride (60% in mineral oil, 0.42 g, 10.5 mmol) at 0° C. After 5 min. a solution of 1-benzylpiperidine-4-carboaldehyde (2.03 g, 10 mmol) in anhydrous THF was added at 0C. After 5 min. the mixture was stirred at room temperature (r.t.) for an additional 30 min and thin layer chromatography (t.l.c.) showed the starting material had disappeared completely. The mixture was quenched with brine and extracted with ethyl acetate. The organic layer was washed with water, dried and concentrated to give the crude product which was purified through silica gel column chromatogrpahy to give the title compound as pale-white solid. 1 HMR (CDCl 3 )δ 1.5-1.7 (m, 4H), 1.9-2.1 (m, 2H), 2.1-2.4 (m, 1H), 2.8-3.0 (m, 2H), 3.5 (s, 2H), 4.9 (ABq, 2H), 6.7 (dd, 1H), 7.9 (s, 1H), 7.1-7.4 (m, ell), 7.7 (d, 1H) ppm.
EXAMPLE 16
2,3-dihydro-7-methoxy2-[[(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]indol-1-one
To a solution of the title compound of Example 4 (5,739 g, 28.5 mmol) in 400 ml dry THF was added sodium hydride (60% in mineral oil, 1.282 g, 32.1 mmol), then 1-benzylpiperidine-4-carboxaldehyde (6.14 g, 30.2 mmol) at 0° C. The ice-bath was removed and the mixture was stirred at r.t. for 30 min (t.l.c. showed no starting material left). The mixture was quenched with 100 ml of saturated ammonium chloride and 300 ml of ethyl acetate. The organic layer was washed with brine, dried and concentrated to give 10.268 g of yellow-brown solid which was purified through silica gel to give 8.790 g (80% yield) of the title compound as a pale-white solid. HNMR (CDCl 3 )δ 1.5-1.75 (m, 4H), 1.9-2.15 (m, 2H), 2.15-2.4 (m, 1H), 3.5 (s, 2H), 3.85 (s, 3H), 4.9 (ABq, 2H), 6.7 (dd, 1H), 6.95 (s, 1H), 7.0-7.15 (m, 2H), 7.2-7.4 (m, 6H) ppm.
The title compounds of Examples 17-27 were prepared using a method similar to that described in Examples 15 and 16, starting from the corresponding substituted 2,3-dihydro-1-oxo-1H-pyrrolo[1,2-a]indole.
EXAMPLE 17
2,3-dihydro-6,7-dimethoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]1H-pyrrolo[1,2-a]indol-1-one was prepared starting from the title compound of Example 5. 1 HNMR (CDCl 3 )δ 1.5-1.7 (m, 4H), 1.9-2.1 (m, 2H), 2.1-2.3 (m, 1H), 3.5 (s, 2H), 3.9 (s, 3H), 3.94 (s, 3H), 4.9 (ABq, 2H), 6.64 (dd, 1H), 6.72 (s, 1H), 6.96 (s, 1H), 7.04 (s, 1H), 7.2-7.3 (m, 5H) ppm.
EXAMPLE 18
2,3-dihydro-7-fluoro-2-[[1-(phenylmethyl)-4-piperidinyl]-methylene]-1H-pyrrolo[1,2-a]indol-1-one was prepared starting from the title compound of Example 6. 1 HNMR (CDCl 3 ) δ 1.5-1.7 (m, 4H), 2.0-2.15 (m, 2H), 2.15-2.4 (m, 1H), 2.8-3.0 (m, 2H), 3.55 (s, 2H), 4.95 (ABq, 2H), 6.75 (dd, H), 7.0 (s, 1H), 7.1-7.2 (m, 1H), 7.2-7.4 (m, 7H) ppm.
EXAMPLE 19
2,3-dihydro-7-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene-1H-pyrrolo]1,2-a]indol-1-one was prepared starting from the title compound of Example 7. 1 HNMR (CDCl 3 )δ 1.5-1.8 (m, 4H), 1.9-2.15 (m, 2H), 2.15-2.35 (m, 1H), 2.42 (s, 3H), 2.8-3.0 (m, 2H), 3.52 (s, 2H), 4.88 (ABq, 2H), 6.7 (dd, 1H), 6.96 (s, 1H), 7.1-7.4 (m, 7H), 7.5 (s, 1H) ppm.
EXAMPLE 20
2,3-dihydro-6-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene-1H-pyrrolo]1,2-a]indol-1-one was prepared starting from the title compound of Example 8. 1 HNMR (CDCl 3 )δ 1.5-1.8 (m, 4H), 2.0-2.15 (m, 2H), 2.15-2.35 (m, 1H), 2.5 (s, 3H), 2.95 (m, 2H), 3.55 (s, 2H), 4.95 (ABq, 2H), 6.75 (m, 1H), 7.0 (d, 1H), 7.05 (s, 1H), 7.15-7.4 (m, 6H), 7.65 (d, 1H) ppm.
EXAMPLE 21
2,3-dihydro-6-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene-1H-pyrrolo]1,2-a]indol-1-one was prepared starting from the title compound of Example 9. 1 HNMR (CDCl 3 )δ 1.55-1.8 (m, 4H), 2.0-2.15 (m, 2H), 2.15-2.4 (m, 1H), 2.95 (m, 2H), 3.5 (s, 2H), 3.9 (s, 3H), 4.9 (ABq, 2H), 6.7 (m, 2H), 6.85 (dd, 1H), 7.05 (s, 1H), 7.2-7.4 (m, 5H), 7.6 (d, 1H) ppm.
EXAMPLE 22
2,3-dihydro-7-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene-1H-pyrrolo]1,2-a]indol-1-one was prepared starting from the title compound of Example 10. 1 HNMR (CDCl 3 )δ 1.4 (t, 3H), 1.5-1.8 (m, 4H), 2.0-2.15 (m, 2H), 2.2-2.4 (m, 1H), 2.85-3.0 (m, 2H), 3.5 (s, 2H), 4.05 (g, 2H), 4.95 (ABg, 2H), 6.7 (m, 1H), 6.98 (s, 1H), 7.0-7.1 (m, 2H), 7.2-7.4 (m, 6H) ppm.
EXAMPLE 23
2,3-dihydro-7-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene-1H-pyrrolo]1,2-a]indol-1-one was prepared starting from the title compound of Example 11. 1 HNMR (CDCl 3 )δ 1.5-1.8 (m, 4H), 2.0-2.15 (m, 2H), 2.15-2.4 (m, 1H), 2.9-3.0 (m, 2H), 3.55 (s, 2H), 4.9 (d, 2H), 5.1 (s, 2H), 6.7 (m, 1H), 7.0 (s, 1H), 7.1-7.2 (m, 2H), 7.2-7.5 (m, 11H) ppm.
EXAMPLE 24
2,3-dihydro-8-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene-1H-pyrrolo]1,2-a]indol-1-one was prepared starting from the title compound of Example 12. 1 HNMR (CDCl 3 )δ 1.5-1.8 (m, 4H), 1.9-2.1 (m, 2H), 2.1-2.3 (m, 1H), 2.5 (s, 3H), 2.9 (m, 2H), 3.5 (s, 2H), 4.9 (ABq, 2H), 6.7 (m, 1H), 6.9 (d, 1H), 7.05 (s, 1H) 7 .1-7.3 (m, 7H) ppm.
EXAMPLE 25
2,3-dihydro-8-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene-1H-pyrrolo]1,2-a]indol-1-one was prepared starting from the title compound of Example 13. 1 HNMR (CDCl 3 )δ 1.55-2.1 (m, 6H), 2.15-2.35 (m, 1H), 2.95 (m, 2H), 3.55 (s, 2H), 3.95 (s, 3H), 4.95 (ABq, 2H), 6.5 (d, 1H), 6.7 (m, 1H), 7.0 (d, 1H), 7.2-7.4 (m, 7H) ppm.
EXAMPLE 26
2,3-dihydro-7(p-tosyloxy)-2-[[1-(phenylmethyl)-4-piperidinyl]methylene-1H-pyrrolo]1,2-a]indol-1-one was prepared starting from the title compound of Example 14. 1 HNMR (CDCl 3 )δ (1.4-1.7 (m, 4H), 1.95-2.1 (m, 2H), 2.1-2.3 (m, 1H), 2.4 (m, 3H), 2.9 (m, 2H), 3.5 (s, 2H), 4.9 (ABq, 2H), 6.7 (m, 1H), 6.94 (s, 1H), 7.0 (dd, 1H), 7.15-7.35 (m, 9H), 7.65 (d, 2h) ppm.
EXAMPLE 27
2,3-dihydro-9-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene-1H-pyrrolo]1,2-a]indol-1-one was prepared starting from 2,3-dihydro-1-oxo-9-methyl-1-pyrrolo[1,2-a]indole 1 HNMR (CDCl)δ 1.5-1.8 (m, 4H), 1.95-2.1 (m, 2H), 2.1-2.3 (m, 1H), 2.6 (s, 3H), 2.9 (m, 2H), 3.52 (s, 2H), 4.88 (ABq, 2H), 6.66 (dd, 1H), 7.1-7.4 (m, H), 7.68 (d, 1H) ppm.
EXAMPLE 28
2,3-dihydro-2-[[1-phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo]1,2-a]indol-1-one
The title compound of Example 15 (650 mg, 1.83 ol) was dissolved in a mixture of solvents of EtOAc (40 mL), THF (70 ml) and methanol (50 mL) and treated with PtO 2 (70 mg) and hydrogenated at 45 psi and at room temperature for 1 hour (t.l.c. indicated no starting material left). The mixture was filtered through diatomaceous earth (Celite (trademark)). The filtrate was concentrated to dryness to give the title compound as a pale-white solid. 1 HNMR (CDCl 3 ) δ 1.2-1.8 (m, 6H), 1.8-2.1 (m, 3H), 2.8-3.0 (m, 2H), 3.15-3.3 (m, 1H), 3.45 (s, 2H), 3.95 (dd, 1H), 4.55 (dd, 1H), 6.93 (s, 1H), 7.0-7.4 (m, 8H), 7.65 (d, 1H) ppm.
EXAMPLE 29
2,3-dihydro-7-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene-1H-pyrrolo]1,2-a]indol-1-one
The title compound of Example 16 (4.702 g, 12.2 ol) was dissolved in a mixture of solvents of ethyl acetate (500 ml) and ethanol (500 ml) and treated with PtO (511 mg) and hydrogenated at 30 psi at r.t. for 1.25 hr. The mixture was filtered through diatomaceous earth (Celite (trademark)) and the filtrate was concentrated to give 4,730 g (99.8%) of the title compound as a beige solid which was recrystallized from ethyl acetate to give white crystals. H (CDCl 3 )δ 1.2-1.8 (m, 6H), 1.82-2.1 (m, 3H), 2.77-2.99 (m, 2H), 3.08-3.24 (m, 1H), 3.44 (s, 2H), 3.8 (s, 3H), 3.9 (dd, 1H), 4.48 (d, 1H), 6.9 (s, 1H), 6.9-7.1 (2H), 7.1-7.3 (m, 6H) ppm. The title compound was resolved with (S)-mandelic acid and (R)-mandelic acid to give the corresponding (-) and (+) enantiomers, respectively, having [α] D 25 values of -6.3° and +3°, respectively.
The title compounds of Examples 30-40 were prepared by a method analogous to that described in examples 28 and 29, starting from the corresponding title compounds of Examples 7-27.
EXAMPLE 30
2,3-dihydro-6,7-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene-1H-pyrrolo]1,2-a]indol-1-one was prepared starting from the title compound of Example 17. 1 HNMR (CDCl 3 )δ 1.2-1.8 (m, 6H), 1.8-2.2 (m, 3H), 2.8-2.95 (m, 2H), 3.15-3.3 (m, 1H), 3.5 (s, 2H), 3.9 (s, 3H), 3.95 (s, 3H), 4.0 (dd, 1H), 4.55 (dd, 1H), 6.75 (s, 1H), 6.9 (s, 1H), 7.06 (s, 1H), 7.25-7.4 (m, 5H) ppm.
EXAMPLE 31
2,3-dihydro-7-fluoro-2]]1-phenylmethyl)-4-piperidinyl]methylene-1H-pyrrolo]1,2-a]indol-1-one was prepared starting from the title compound of Example 18. 1 HNMR (CDCl 3 )δ 1.2-1.8 (m, 6H), 1.8-2.2 (m, 3H), 2.8-3.0 (m, 2H), 3.15-3.3 (m, 1H), 3.5 (s, 2H), 4.0 (dd, 1H), 4.6 (dd, 1H), 4.6 (dd, 1H), 6.9 (s, 1H), 7.1-7.2 (m, 1H), 7.2-7.4 (m, 7H) ppm.
EXAMPLE 32
2,3-dihydro-7-methyl-2-[[1-(phenylmethy)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one was prepared from the title compound of Example 19. 1 HNMR (CDCl)δ 1.2-1.8 (m, 6H), 1.8-2.1 (m, 3H), 2.45 (s, 3H), 2.85-3.05 (m, 2H), 3.1-3.3 (m, 1H), 3.5 (s, 2H), 3.95 (dd, 1H), 4.5 (dd, 1H), 6.85 (s, 1H), 7.1-7.4 (m, 7H), 7.5 (s, 1H) ppm.
EXAMPLE 33
2,3-dihydro-6-methyl-2O[[1-(phenylmethyl)-4 -piperidinyl]methyl]-1H-pryrrolo[1,2-a]indol-1-one was prepared starting from the title compound of Example 20. 1 HNMR (CDCl)δ 1.4-1.7 (m, 4H), 1.7-1.85 (m, 2H), 2.0. -2.2 (m, 3H), 2.5 (s, 3H), 3.0 (m, 2H), 3.15-3.3 (m, 1H), 3.6 (s, 2H), 4.0 (dd, 1H), 4.55 (dd, 1H), 6.95 (s, 1H), 7.0 (d, 1H), 7.2 (s, 1H), 7.2-7.4 (m, 5H), 7.6 (d, 1H) ppm.
EXAMPLE 34
2,3-dihydro-6-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo]1,2-a]indol-1-one was prepared starting from the title compound of Example 21. 1 HNMR (CDCl 3 )δ 1.3-1.8 (m, 6H), 1.9-2.2 (m, 3H), 2.8-3.0 (m, 2H), 3.15-3.3 (m, 1H), 3.5 (s, 2H), 3.85 (s, 3H), 3.95 (dd, 1H), 4.55 (dd, 1H), 6.7 (s, 1H), 6.85 (dd, 1H), 6.9 (s, 1H), 7.2-7.4 (m, 5H), 7.6 (d, 1H) ppm.
EXAMPLE 35
3-dihydro-7-ethoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one was prepared starting from the title compound of Example 22. 1 HNMR (CDCl 3 )δ 1.4-1.6 (m, 7H), 1.6-1.8 (m, 2H), 1.9-2.1 (m, 3H), 2.9 (m, 2H), 3.25 (m, 1H), 3.5 (s, 2H), 3.95 (dd, 1H), 4.05 (q, 2H), 4.55 (dd, 1H), 6.9 (s, 1H), 7.0-7.1 (m, 2H), 7.1-7.4 (m, 6H) ppm.
EXAMPLE 36
2,3-dihydro-7-benzyloxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one was prepared starting from the title compound of Example 23. 1 HNMR (CDCl 3 )δ 1.2-1.8 (m, 6H), 1.9-2.1 (m, 3H), 2.9 (m, 2H), 3.25 (m, 1H), 3.55 (s, 2H), 4.0 (dd, 1H), 4.6 (dd, 1H), 5.1 (s, 2H), 6.9 (s, 1H), 7.05-7.2 (m, 2H), 7.2-7.5 (m, 11H) ppm.
EXAMPLE 37
2,3-dihydro-8-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one was prepared starting from the title compound of Example 24. 1 HNMR (CDCl 3 ) δ 1.3-1.8 (m, 6H), 1.9-2.2 (m, 3H), 2.55 (s, 3H), 2.9 (m, 2H), 3.2-3.35 (m, 1H), 3.5 (s, 2H), 4.0 (dd, 1H), 4.6 (dd, 1H), 6.95 (d,1H), 7.0 (s, 1H), 7.2-7.4 (m, 7H) ppm.
EXAMPLE 38
2,3-dihydro-8-methoxy-2-[[-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one was prepared starting from the title compound of Example 25. 1 HNMR (CDCl) δ 1.3-1.8 (m, 6H), 1.9-2.1 (m, 3H), 2.9 (m, 2H), 3.15-3.35 (m, 1H), 3.5 (s, 2H), 3.95 (s, 3H), 4.0 (dd, 1H), 4.6 (dd, 1H), 6.5 (d, 1H), 6.95 (d, 1H), 7.1 (s, 1H), 7.2-7.4 (m, 6H) ppm.
EXAMPLE 39
2,3-dihydro-7-(p-tosyloxy)-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo]1,2-a]indol-1-one was prepared starting from the title compound of Example 26. 1 HNMR (CDCl 3 )δ 1.2-1.7 (m, 6H), 1.8-2.0 (m, 3H), 2.37 (s, 3H), 2.75-2.9 (m, 2H), 3.1-3.3 (m, 1H), 3.42 (s, 2H), 3.92 (dd, 1H), 4.5 (dd, 1H), 6.8 (s, 1H), 6.95 (dd, 1H), 7.1-7.3 (m, 9H), 7.6 (d, 2H) ppm.
EXAMPLE 40
2,3-dihydro-9-methyl-2-[[-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one was prepared starting from the title compound of Example 27.1HNMR (CDCl 3 ) δ 1.2-1.8 (m, 6H), 1.9-2.1 (m, 3H), 2.55 (s, 3H), 2.85-2.95 (m, 2H), 3.15-3.3 (m, 1H), 3.5 (s, 2H), 3.95 (dd, 1H), 4.5 (dd, 1H), 7.15 (dd, 1H), 7.25-7.4 (m, 7H), 7.7 (d, 1H) ppm.
EXAMPLE 41
2,3-dihydro-2-methyl-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one
A solution of 2,3-dihydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one (137 mg, 0.353 mmol) in dry THF (5 ml) was treated with NaH (35 mg, 0.875 mmol) at r.t. After 5 minutes, an excess of methyl iodide (0.1 ml) was added and the mixture was stirred at r.t. for 3 hours. The mixture was quenched with water and extracted with chloroform. The organic layer was dried and concentrated to give 140 mg of material which was purified through silica gel to give the title compound. 1 HNMR (CDCl 3 )δ 1.36 (s, 3H), 1.6-2.2 (m, 7H), 2.4-2.7 (m, 2H), 3.2-3.4 (m, 2H), 3.8 (s, 3H), 4.05 (s, 2H), 4.18 (ABq, 2H), 6.9 (s, 1H), 7.0-7.1 (m, 2H), 7.2-7.3 (m, 1H), 7.3-7.4 (m, 3H), 7.4-7.6 (m, 2H) ppm.
EXAMPLE 42
1,2,3,4-tetrahydro-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]cyclopent[b]indol-1-one
To a mixture of 1,2,3,4-tetrahydrocyclopent[b]-indol-1-one (440 mg, 2.6 mmol) and 1-benzylpiperidine-4-carboxaldehyde (581 mg, 2.86 mmol) in 90 ml dry THF was added 5.4 mmol of lithium diisopropylamide at -78° C. The mixture was stirred at -78° C. for 30 minutes, then warmed up to 0° C. for 1.5 hours, and then to r.t. for 15 minutes. Acetic anhydride (0.265 g, 2.6 mmol) was added, the mixture was stirred at r.t. for 1.5 hours and quenched ammonium chloride, water and extracted with chloroform. The organic layer was dried, concentrated, and purified through silica gel to give the title compound. 1 HNMR (CDCl 3 )δ 1.45-1.7 (m, 3H), 1.8-2.3 (m, 4H), 2.8-3.0 (m, 2H), 3.46 (s, 2H), 3.55 (s, 2H), 6.5 (m, 1H), 7.1-7.4 (m, 8H), 7.9 (m, 1H), 9.2 (s, 1H) ppm.
EXAMPLE 43
1,2,3,4tetrahydro-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]cyclopent[b]indol-1-one
the title compound of Example 42 (176 mg, 0.5 mmol) was dissolved in a mixture solvents of ethyl acetate (31 ml) and ethanol (31 ml) and treated with PtO.sub. 2 (23 mg) and hydrogenated at 35 psi at r.t. for 2 hours. The mixture was filtered through diatomaceous earth (Celite (trademark)) and the filtrate was concentrated to give compound the title compound as off-white solid. 1 HNMR (CDCl 3 )δ 1.3-1.65 (m, 4H), 1.65-1.8 (m, 2H), 1.9-2.1 (m, 3H), 2.65 (dd, 1H), 2.9-3.1 (m, 3H), 3.2 (dd, 1H), 3.55 (s, 2H), 7.15-7.4 (m, 8H), 7.9 (dd, 1H), 9.15 (s, 1H) ppm.
EXAMPLE 44
1,2,3,4-tetrahydro-2-[[(phenylmethyl)-4-piperidinyl]methylene]clopent[b]indol-3-one
A solution of lithium diisopropylamide (10.64 mmol) in dry THF was cooled to -78° C. and to it was added 1,2,3,4-tetrahydrocyclopent[b]indolo-3-one (0.91 g, 5.32 mmol). The mixture was stirred at -78° C. for 30 minutes, then treated with 1-benzylpiperidine-4-carboxylaldehyde (1.29 g, 6.35 mmol) at -78° C. The mixture was warmed to r.t. for 4 hours, quenched with sodium bicarbonate, and extracted with ethyl acetate. The organic layer was dried, concentrated, and recrystallized from a mixture of ethyl acetate and ethanol to give the title compound. 1 HNMR (CDCl 3 )δ 1.63-1.74 (m, 3H), 2.07 (dt, 2H), 2,35-2.55 (m, 1H), 2.95 (brd, 2H), 3.54 (s, 2H), 3.65 (s, 2H), 6.63 (d, 1H), 7.19 (t, 1H), 7.25-7.33 (m, 5H), 7.40 (dt, 1H), 7.51 (d, 1H), 7.69 (d, 1H), 9.51 (s, 1H) ppm.
EXAMPLE 45
1,2,3-tetrahydro-6-methoxy-2-[[1-phenylmethyl)-4-piperidinyl]methyene]cyclopent[b]indol-3 -one
The title compound was prepared by a method analogous to that of Example of 44, starting from 6-methoxy-1,2,3,4-tetrahydrocyclopent[b]indol-3-one. 1 HNMR (CDCl 3 )δ 1.61-1.72 (m, 4H), 2.06 (dt, 2H), 2,36-2.40 (m, 1H), 2.91-2.95 (m, 2H), 3.53 (s, 2H), 3.60 (d, 2H), 3.88 (s, 3H), 6.57 (d, 1H), 6.83 (dd, 1H), 6.88 (d, 1H), 7.26-7.33 (m, 5H), 7.55 (d, 1H), 9.04 (s, 1H) ppm.
EXAMPLE 46
1,2,34-tetrahydro-8-methoxy-2-[[1-(phenymethyl)-4-piperidinyl]methylene]-cyclopent[b]indol-3 -one
The title compound was prepared by a method analagous to that described in Example 44, starting from 4-methoxy-1,2,3,8-tetrahydrocyclopent[b]indol-1-one. 1 HNMR (DMSO-d 6 )δ 1.42-1.53 (m, 2H), 1.66-1.69 (m, 2H), 2.04 (t, 2H), 2,38-2.5 (m, 1H), 2.81-2.85 (m, 2H), 3.48 (s, 2H), 3.70 (s, 2H), 3.90 (s, 3H), 6.35 (d, 1H), 6.58 (d, 1H), 6.99 (d, 1H), 7.24-7.34 (m, 6H), 11.8 (s, 1H) ppm.
EXAMPLE 47
1,2,3,4-tetrahydro-2-[[1-phenylmethyl)-4-piperidinyl]methylene]cyclopent[b]indol-3-one
A solution of the title compound of Example 44 in a mixture of acetic acid and ethanol was treated with PtO 2 and hydrogenated at 45 psi for 16 hours. The mixture was filtered through diatomaceous earth (Celite (trademark)) and the filtrate was concentrated, purified through silica gel column to give the title compound. 1 HNMR (CDCl 3 )δ 1.35-1.55 (m, 4H), 1.68-1.80 (m, 2H), 1.93-2.70 (m, 3H), 2.75 (d, 1H), 2.90-2.95 (m, 2H), 3.05-3.09 (m, 1H), 3.30 (dd, 1H), 3.55 (s, 2H), 7.16 (t, 1H), 7.25-7.32 (m, 5H), 7.38 (t, 1H), 7.48 (d, 1H), 7.67 (d, 1H), 9.52 (brs, 1H) ppm.
EXAMPLE 48
1,2,3,4-tetrahydro-6-methoxy-2-[[1-phenylmethyl)-4-piperidinyl]methyl]cyclopent[b]indol-3-one
The title compound was prepared by a method analogous to that described in Example 47 starting from the title compound of Example 45. 1 HNMR (CDCl)δ 1.3-1.6 (m, 3H), 1.65-1.80 (m, 3H), 1.93-2.0 (m, 3H), 2.7 (dd, 1H), 2.85-2.95 (m, 2H), 3.1-3.1 (m, 1H), 3.24 (dd, 1H), 3.5 (s, 2H), 3.87 (s, 3H), 6.81 (dd, 1H), 6.86 (d, 1H), 7.23-7.31 (m, 5H), 7.53 (d, 1H), 9.07 (brs, 1H) ppm.
EXAMPLE 49
The title compound was prepared by a method analogous to that described as in Example 47 starting from the title compound of Example 46. 1 HNMR (CDCl 3 )δ 1.32-1.53 (m, 4H), 1.65-1.69 (m, 1H), 1.76-1.80 (m, 1H), 1.91-2.12 (m, 3H), 2.85 (dd, 1H), 2.88-2.95 (m, 2H), 3.00-3.05 (m, 1H), 3.38 (dd, 1H), 3.51 (s, 2H), 3.93 (s, 3H), 6.48 (d, 1H), 7.04 (d, 1H), 7.24-7.32 (m, 6H), 9.49 (brs, 1H) ppm.
EXAMPLE 50
1,2,3,4-tetrahydro-8-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]cyclopent[b]indol-3-one
A solution of 1,2,3,4-tetrahydro-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-cyclopent[b]indol-1-one (350 mg, 1 mmol) in dry THF was treated with 60% sodium hydride in oil (48 mg, 1.2 mmol) and Mel (1.3 mmol) at r.t. The mixture was stirred at r.t. overnight, quenched with water and extracted with ethyl acetate. The organic layer was dried and concentrated to give the title compound. 1 HNMR (CDCl)δ 1.55-1.68 (m, 1H), 1.75-2,35 (m, 5H), 2.60-2.80 (m, 3H), 2.95-3.05 (m, 1H), 3.27 (dd, 1H), 3.35-3.57 (m, 2H), 3.86 (s, 3H), 4.15 (s, 2H), 7.15 (t, 1H), 7.34 (t, 1H), 7.37-7.44 (m, 4H), 7.62-7.65 (m, 3H) ppm.
EXAMPLE 51
2,3-dihydro-1-oxo-1H-pyrrolo[1,2-a]benzimidazole
A solution of 2,3-dihydro-1-hydroxy-1H-pyrrolo-[1,2-a]benzimidazole (1.0 g, 5.75 mmol)) in methylene chloride was treated with mangenese dioxide (5 g, 58 mmol) at r.t. and stirred for 10 hour. The mixture was diluted with ethyl acetate and filtered through diatomaceous earth (Celite (trademark)). The filtrate was concentrated and purified to give the title compound. 1 HNMR (CDCl 3 )δ 3.28 (t, 2H), 4.48 (t, 2H), 7.3-7.45 (m, 2H), 7.45-7.55 (m, 1H), 7.86-7.94 (m, 1H) ppm.
EXAMPLE 52
2,3-dihydro-2- [[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]benzimidazol-1-one
To a solution of 2,3-dihydro-1-oxo-1H-benzimidazole (200 mg, 1.17 mmol) in dry THF was added NaH and 1-benzylpiperidine-4-carboxaldehyde (240 mg, 1.16 mmol) at 0° C. The mixture was stirred at that temperature for 30 minutes then stirred at r.t. for 1 hour. The mixture was then quenched with saturated ammonium chloride and water and then extracted with chloroform. The organic layer was dried, concentrated, and purified from silica gel to give the title compound as a yellow solid. 1 HNMR (CDCl 3 )δ 1.4-1.7 (m, 4H), 1.9-2.1 (m, 2H), 2.1-2.3 (m, 1H), 2.7-2.9 (m, 2H), 3.44 (s, 2H), 4.92 (ABq, 2H), 6.85 (m, 1H), 7.1-7.5 (8H), 7.85 (m, 1H) ppm.
EXAMPLE 53
2,3-dihydro-2-[[--(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a]benzimidazol- 1-one
A solution of the compound of Example 52 (190 mg, 0.53 mmol) in 60 ml of a 1:1 mixture of THF and ethanol was treated with PtO 2 (20 mg) and hydrogenated at 45 psi at r.t. for 30 minutes. The mixture was filtered through diatomaceous earth (Celite (trademark)) and the filtrate was concentrated to give a tan solid. The tan solid was purified through silica gel to give compound. 1 HNMR (CDCl 3 ) δ 1.3-2.2 (m, 9H), 2.7-2.9 (m, 2H), 3.3-3.4 (m, 1H), 3.5 (s, 2H), 4.1 (dd, 1H), 4.7 (dd, 1H), 7.2-7.6 (m, 8H), 8.0 (m, 1H) ppm.
EXAMPLE 54
2,3-dihydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a[indol-1-ol
To a solution of 2,3-dihydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2a]indol-1-one (200 mg, 0.515 mmol) in EtOH (10 ml) was treated with sodium borohydride (22.5 mg, 0,595 mmol) at r.t. After 30 minutes, the mixture was heated to reflux for hour, quenched with water and extracted with methylene chloride. The organic layer was dried and concentrated to give 180 mg of a mixture of diasteromers of the title compound as a white solid. 1 HNMR (CDCl)δ 1.2-2.2 (m, 10H), 2.8-3.0 (m, 2H), 3.5 (2 sets of s, 2H), 3.55-3.8 (m, 1H), 3.8 (s, 3H), 4.1 (dd, 0.6H), 4.35 (dd, 0.4H), 4.9 (d, 0.6H), 5.05 (d, 0.4H), 6.25 (s, 0.6H), 6.3 (s, 0.4H), 6.85 (m, 1 H), 7.1 (m, 1H), 7.15 (m, 1H), 7.2-7.4 (m, 5H) ppm.
EXAMPLE 55
2,3-dihydro-1-acetoxy-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a[indole
A solution of the title compound of Example 54 (210 mg, 0.54 mmol) in 10 ml of methylene chloride was treated with acetic anhydride (83 mg, 0.81 mmol) and pyridine (72 mg, 0.91 mmol) and stirred at r.t. for 5 hour. The mixture was quenched with water and the organic layer was separated, dried and concentrated to give 219 mg of yellow oil which was purified through silica gel column chromatography to give the title compound as a yellow oil. 1 HNMR (CDCl 3 )δ 1.2-2.0 (m, 9H), 2.0 (s, 0.4H), 2.05 (s, 0.6H), 2.8-2.9 (m, 2H), 2.9-3.1 (m, 1H), 3.59 (m, 2H), 3.65-3.8 (m, 1H), 3.85 (s, 3H), 4.2 (dd, 0.4H), 4.35 (dd, 0.6H), 5.8 (d, 0.6H), 6.05 (d, 0.4H), 6.32 (s, 0.6H), 6.35 (s, 0.4H), 6.8 (m, 1H), 7.0 (m, 1H), 7.2-7.4 (m, 5H) ppm.
EXAMPLE 56
2,3-dihydro-1-methyl-2-[[1-(phenylethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-ene
To a solution of methylmagnesium bromide (5.16 mol) in 25 ml of dry tetrahydrofuran was added a solution of 2,3-dihydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one (1 g, 2.58 mmol) in dry THF (25 ml) at 0° C. The mixture was stirred at that temperature for 2 hours and then warmed to r.t., quenched with 1N HCl to pH 1 and extracted with chloroform. The organic layer was washed with saturated sodium bicarbonate and brine, dried and concentrated to give the crude material which was purified through silica gel to give the title compound. 1 HNMR (CDCl 3 )δ 1.45-2.0 (m, 5H), 2.0 (s, 3H), 2.3-2.6 (m, 4H), 3.25 (m, 2H), 3.7 (s, 2H), 3.8 (s, 2H), 3.9 (s, 2H), 6.74 (s, 1H), 6.76 (dd, 1H), 6.94 (s, 1H), 7.02 (d, 1H), 7.3-7.6 (m, 5H) ppm. 13 NMR (CDCl 3 ) 9.7, 28.4, 29.9, 32.2, 36.0, 52.8, 55.8, 61.4, 107.5, 109.1, 111.8, 112.8, 124.7, 128.9, 129.1, 130.8, 132.2, 135.0, 135.8, 55.7 ppm.
EXAMPLE 57
2,3-dihydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-oxime
A solution of 2,3-dihydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1- one (100 mg, 0.26 mmol) in EtOH (25 ml) and water (25 ml) was treated with hydroxylamine hydrochloride (54 mg) and sodium acetate (105 mg) at r.t. The mixture was refluxed for 24 hours, cooled to r.t. and the ethanol was removed. The residue was washed with water and extracted with chloroform. The organic layer was dried and concentrated to give a yellow solid. The yellow solid was purified through silica gel column to give the title compound as a mixture of diasteromers. 1 HNMR (CDCl 3 )δ 1.4-2.1 (m, 9H), 2.9-3.1 (m, 2H), 3.5-3.7 (m, 3H), 3.95 (s, 3H), 4.25-4.45 (m, 1H), 6.8-7.0 (m, 2H), 7.0-7.2 (m, 2H), 7.2-7.4 (m, 5H) ppm.
EXAMPLE 58
2,3-dihydro-6-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene-1H-cyclopent[b]benzofuran-1-one
The title compound was prepared by a method analogous to that described in Example 44, starting from 2,3-dihydro-6-methoxy-1H-cyclopent[b]benzofuran-1-one. A 79% yield of the title compound was obtained as a pale yellow solid. The material was recrystallized from ethyl acetate to give pale yellow needles, mp. 200°-201° C.; Anal. Calc. for CH 25 H 25 NO 3 : C, 77.49; H, 6.50; N, 3.61; Found C, 77.33; H, 6.51; N, 3.64.
EXAMPLE 59
1,2,3,4-tetrahydro-6-methoxy-2-[[1-(t-butoxycarbonyl-4-piperidinyl]methylene]cyclopent[b]indol-3-one
The title compound was prepared by a method analogous to that described in Example 44, starting from 6-methoxy-1,2,3,4-tetrahydrocyclopent[b]indol-3-one and 1-(t-butoxycarbonyl)piperidine-4-carboxaldehyde, mp. 235°-236° C. (dec.); Anal. Calc. for C 23 H 28 N 2 O 4 : C, 69.68; H, 7.12; N, 7.07; Found: C, 69.67; H, 6.90; N, 6.98.
EXAMPLE 60
1,2,3,4-tetrahydro-6-methoxy-2-[[1-(t-butoxycarbonyl)-4-piperidinyl]methyl]cyclopent[b]indol-3-one
PtO 2 (80 mg, 0.31 mmol) was added to a solution of the title compound of Example 59 (610 mg, 1.54 mmol) in 1:1 THF/EtOH (tetrahydrofuran/ethanol). The resulting mixture was hydrogenated at 50 psi for 7 hours. The reaction mixture was filtered through diatomaceous earth (Celite (trademark)). The filtrate was concentrated and the residue obtained was purified by chromatography to give the title compound (550 mg, 90%) as a pale yellow solid. Recrystallization from ethyl acetate/hexane of the material gave a white solid, mp. 192°-193° C.; Anal. Calc. for C 23 H 30 N 2 O 4 : C, 69.32; H, 7.59; N, 7.03; found: C, 69.40; H, 7.39; N, 7.02.
EXAMPLE 61
1,2,3,4-tetrahydro-6-methoxy-2-[[1-(t-butoxycarbonyl)-4-piperidinyl]methyl]cyclopent[b]indol-3 -thione
Lawesson's reagent (244 mg, 0.60 mmol) was added to a mixture of the title compound of Example 60 (400 mg, 1.01 mmol) in toluene and the resulting mixture was heated to 80° C. for 15 minutes. The reaction mixture was concentrated and the residue was purified by chromatography to give the title compound (280 mg, 67%) as an orange solid. Recrystallization from ethyl acetate gave orange crystals, mp. 188°-189° C.; Anal. Calc. for C 23 H 30 N 2 O 3 S: C, 66.64; H, 7.29; N, 6.76; Found: C, 66.42; H, 7.17; N, 6.59.
EXAMPLE 62
1,2,3,4-tetrahydro-6-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]cyclopent[b]indol-3-thione
Trifluoroacetic acid (7.5 ml) was added to a solution of the title compound of the Example 61 (200 mg, 0.483 mmol) and thioanisole (0.85 ml, 7.25 mmol) in methylene chloride at 0° C. After 1.5 hours, the mixture was concentrated and the residue dissolved in ethyl acetate. The organic layer was washed with 1N sodium hydroxide and brine, dried, and concentrated. The crude residue was dissolved in methylene chloride and triethylamine (0.162 ml, 1.16 mmol), followed by addition of benzyl bromide (0.069 ml, 0.58 mmol). The resulting mixture was stirred at room temperature for 24 hours. The reaction mixture was washed with saturated sodium bicarbonate, dried, and concentrated. The residue was purified by silica gel column chromatography to give the title compound (140 mg) as an orange solid. Recrystallization from ethyl acetate gave orange crystals, mp. 180°-181° C.; Anal. Calc. for C 25 H 28 N 2 OS.0.5H 2 O: C, 72.60; H, 7.07; N, 6.77; Found: C 72.72; H, 6.88; N, 6.63.
EXAMPLE 63
6,7-dihydro-6-[[-(phenylmethyl)-4-piperidiny]methyene]-5H-thieno[3,2-b]pyrrolizine-5-one
The title compound was prepared by a method analogous to that described in Example 15, starting from 2,3-dihydro-1 H-pyrrolo[1,2a](thieno[2,3-b]pyrrol)-1-one and 1-benzylpiperidine-4-carboxaldehyde. 1 H NMR (CDCl 3 )δ 1.54 (m, 4H), 1.96-2.1 (m, 2H), 2.1-2.3 (m, 1H), 2.85-3.0 (m, 2H), 3.52 (s,2H), 4.9 (d,2H), 6.65 (m, 1H), 6.9-7.1 (m, 2H), 7.2 7.4 (m, 5H) ppm.
EXAMPLE 64
6,7-dihydro-6-[[(phenylmethyl)-4-piperidinyl]methyl]-5H-thieno[3,2-b]-pyrrolizine-5-one
The title compound was prepared by hydrogenation of the title compound in Example 63 by a method analogous to that described in Example 28. 1 H NMR (CDCl 3 )δ 1.3-2.2 (m,9H), 2.9 (m, 2H), 3.15-3.35 (m, 1H), 3.5 (s,2H), 3.95 (mm, 1H), 4.5 (dd,1H), 6.9 (s,1H), 7.0 (ABq,2H), 7.3-7.4 (m,5H) ppm.
EXAMPLE 65
2,3-dihydro-7-methoxy-2-[[1(phenylmethyl)-4-piperidinyl]methylene]-1H-pyrrolo[1,2-a](6-azaindol)-1-one
The title compound was prepared by a method analogous to that described in example 15, starting from 2,3-dihydro-7-methoxy-1H-pyrrolo[1,2-a](6-azaindol)-1-one and 1-benzylpiperidine-4-carboxaldehyde. 1 H NMR (CDCl 3 )δ 1.5-2.35 (m, 7H), 2.9 (m,2H), 3.5 (s,2H), 3.9 (s,3H), 4.98 (d,2H), 6.75 (m, 1H), 6.82 (s,1H), 6.92 (s,1H), 7.2-7.3 (m,5H), 8.5 (s, 1H) ppm.
EXAMPLE 66
ethyl 3-[[1-phenylmethyl)-4-piperidinyl]ethylamino]methyl-6-methylindole-2-carboxylate
A mixture of ethyl 3-formyl-6-methylindol-2-carboxylate (2.0 g, 8.7 mmol) and 1-benzylpiperidine-4-ethylamine was dissolved in 1:1 ethanol/THF and treated with anhydrous sodium acetate, anhydrous sodium sulfate, and sodium cyanoborohydride. The mixture was stirred at room temperature overnight. The mixture was filtered. The filtrate was concentrated to dryness. The residue was diluted with water and extracted with ethyl acetate. The organic layer was separated, dried, and concentrated to give a yellow oil. The oil was purified through silica gel column chromatography to give the title compound as a yellow oil, 1 H NMR (CDCl 3 )δ 1.1-1.35 (m,2H), 1.4 (t,3H), 1.5-1.8 (m,5H), 1.8-2.0 (m,2H), 2.45 (s,3H), 2.6 (t,2H), 2.8 (m,2H), 3.44 (s,2H), 4.2 (s,2H), 4.4 (q,2H), 6.96 (d,1H), 7.14 (s,1H), 7.2-7.35 (m,5H), 7.6 (d,1H), 8.62 (brs,1H) ppm.
EXAMPLE 67
ethyl 3-[[1-phenylmethyl)-4-piperidinyl]ethylamino]methyl-5-methyl-indole-2-carboxylate
The title compound was prepared by the method analogous to that described in Example 66, starting from ethyl 3-formyl-5-methyl-indole-2-carboxylate. 1 H NMR (CDCl 3 )δ 1.42 (t,3H), 1.3-1.6 (m,2H), 1.6-1.8 (m,5H), 2.4 (s,3H), 2.5-2.7 (m,2H), 3.0 (t,2H), 3.05-3.2 (m,2H), 3.85 (s,2H), 4.3-4.6 (m,4H), 7.15 (d, 1H), 7.24 (s,1H), 7.3-7.5 (m,5H), 7.53 (s, 1H), 9.85 (brs, 1H) ppm.
EXAMPLE 68
ethyl 3-[[1-phenylmethyl)-4-piperidinyl]ethylamino]methyl-6-methoxyindole-2-carboxylate
The title compound was prepared by the method analogous to that described in Example 66, starting from ethyl 3-formyl-6-methoxyindole-2-carboxylate. 1 H NMR (CDCl)δ 1.1-1.7 (m,7H), 1.36 (t,3H), 1.8-2.0 (m,2H), 2.67 (t,2H), 2.80 (m,2H), 3.44 (s,2H), 3.78 (s,3H), 4.15 (s,2H), 4.32 (q,2H), 6.7-6.8 (m,2H), 7.1-7.3 (m,5H), 7.5 (d,1H) ppm.
EXAMPLE 69
3-[[1-phenylmethyl)-4-piperidinyl]ethylamino]methyl-6-methyl-indole-2-carboxylic acid
A solution of the title compound of Example 66 (521 mg, 1.2 mmol) in 5 ml of dioxane was treated with 2.0 ml of 0.5 M aqueous lithium hydroxide at room temperature. The mixture was stirred at room temperature overnight and quenched with 0.9 ml of 2.2N HCl gas in dioxane and concentrated to dryness. The residue was diluted with water and extracted twice with chloroform. The organic layer was dried and concentrated to give the title compound as an oil, 1 H NMR (CD 3 OD)δ 1.35-1.5 (m,3H), 1.6-1.7 (m,4H), 1.8-1.95 (m,2H), 2.4 (s,3H), 2.8 (dt,2H), 3.05 (t,2H), 4.1 (s,2H), 4.4 (s,2H), 6.95 (d, 1H), 7.2 (s,1H), 7.35-7.5 (m,5H), 7.52 (d, 1H) ppm.
EXAMPLE 70
3-[[1-phenylmethyl)-4-piperidinylamino]methyl-5-methyl-indole-2-carboxylic acid
The title compound was prepared by hydrolysis of ethyl 3-[[1-(phenylmethyl)-4-piperidinyl]ethylamino]methyl-5- methyl-indole-2-carboxylate by the method analogous to that described in Example 69. 1 H NMR (CD 3 OD)δ 1.35-2.0 (m, 9H), 2.4 (s, 3H), 2.9-3.15 (m, 1H), 3.45 (m,2H), 4.28 (s,2H), 4.45 (s,2H), 7.1 (d,1H), 7.35 (d,1H), 7.45-7.6 (m,6H) ppm.
EXAMPLE 71
3-[[phenylmethyl)-4 -piperidinyl]ethylamino]methyl-6-methoxyindole-2-carboxylic acid
The title compound was prepared by hydrolysis of ethyl 3-[[1-(phenylmethyl)-4 -piperidinyl]ethylamino]methyl-6-methoxy-indole-2-carboxylate by the method analogous to that described in Example 69. 1 H NMR (CD 3 OD)δ 1.4-1.55 (m, 2H), 1.65-1.8 (m, 3H), 1.8-1.9 (m, 2H), 2.85-2.95 (m, 2H), 3.08 (t,2H), 3.8 (s,3H), 4.2 (s,2H), 4.4 (s,2H), 6.75 (dd, 1H), 6.9 (d,1H), 7.4-7.6 (m,6H) ppm.
EXAMPLE 72
1,2,3,4-tetrahydro-6-methyl-2-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]pyrrolo[3,4-[b]indol-3-one
A solution of 3-[[1-(phenylmethyl)-4-piperidinyl]ethylamino]methyl-6-methyl-indole-2-carboxylic acid (330 mg, 0.815 mmol) in DMF (4 ml) was treated with dimethylaminopyridine (20 mg, 0.163 mmol), 4-methylmorpholine (83 mg, 0.815 mmol) and 1-(3-dimethylaminopropyl)-3-ethyl carbodimide hydrochloride (192 mg, 1 mmol) and stirred at room temperature for 19 hours. The mixture was treated with ethyl acetate and washed with sodium bicarbonate. The organic layer was washed with brine, dried, and concentrated to give the crude product. The crude material was trifurated with ethyl/acetate to give the title compound as a pale yellow solid. Recrystallization from ethyl acetate gave a pale yellow solid, mp. 189°-191° C.; Anal. Calc. for C 25 H 29 N 3 O.0.3H 2 O: C, 76.41; H, 7.59; N, 10.69; Found: C, 76.12; H, 7.23; N, 10.53.
EXAMPLE 73
1,2,3,4-tetrahydro-7-methyl-2-[[2-[-1(phenymethyl)-4-piperidinyl]ethyl]pyrrolo[3,4-b]indol-3-one
The title compound was prepared by the method analogous to that described in Example 72, starting from 3-[[1-(phenylmethyl)-4 -piperidinyl]ethylamino]methyl-5-methyl-indole-2-carboxylic acid. Anal. Calc. for C 24 H 29 N 3 O: C, 76.76; H, 7.78; N, 11.19; Found: C, 76.80; H, 7.44; N, 10.72.
EXAMPLE 74
1,2,3,4-tetrahydro-6-methoxy-2-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]-pyrrolo[3,4-bindol-3-one
The title compound was prepared by the method analogous to that described in Example 72, starting from 3-[[1-(phenylmethyl)-4-piperidinyl]ethylamino]methyl-6-methoxy-indole-2-carboxylic acid. 1 H NMR (CDCl 3 )δ 1.2-1.4 (m,3H), 1.55-1.68 (m, 2H), 1.68-1.84 (m, 2H), 1.84-2.0 (m, 2H), 2.85 (m,2H), 3.44 (s,2H), 3.64 (5,2H), 3.82 (s,3H), 34.36 (s,2H), 6.8 (dd,1H), 6.95 (d, 1H), 7.16-7.3 (m,5H), 7.42 (d,1H) ppm.
EXAMPLE 75
2,3-dihydro-7-hydroxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1one
A solution of 2,3-dihydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one (1.599 g, 4.12 mmol) in 95 ml of methylene chloride was treated with potassium carbonate (5.696 g, 41.2 mmol) and cooled to -78° C. Boron tribromide (BBr 3 ) was added dropwise to the cooled solution. After addition, the resulting solution was stirred at 0° C. for one hour, then at room temperature overnight. The mixture was treated with 36 g of potassium carbonate and 100 ml of water and stirred for one hour. The organic layer was separated, washed with water, dried and concentrated to give 1.652 g of yellow solid which was purified through silica gel column chromatography to give 0.988 g of the title compound. This material was recrystallized from ethyl acetate to give brown crystals, mp. 186°-188° C. Anal. Calc. for C 24 H 26 N 2 O 2 .0.1H 2 O: C, 76.60; H, 7.02; N, 7.45; Found C, 76.45; H, 7.18; N, 7.38.
EXAMPLE 76
2,3-dihydro-7-acetoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-H-pyrrolo[1,2-a]indol-1-one
A solution of 2,3-dihydro-7-hydroxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-1-one (255 mg, 0.68 mmol) in 25 ml of methylene chloride was treated with acetic anhydride (83 mg, 0.81 mmol) and triethyl amine (93 mg, 0.91 mmol) and stirred at room temperature overnight. The mixture was quenched with water and the organic layer was separated, dried, and concentrated to give 244 mg of title compound as an off-white solid. The solid was recrystallized from ethyl acetate to give white powder, mp. 140.5°-141.5° C. ; Anal. Calc. for C 26 H 28 N 2 O 3 : C, 74.97; H, 6.78; N, 6.73; Found: C, 74.70; H, 6.72; N, 6.66.
EXAMPLE 77
2,3-dihydro-1-oxo-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-pyrrolo[1,2-a]indol-7-ol, N-methyl carbamate ester
A solution of 2,3-dihydro-7-hydroxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl-1H-pyrrolo[1,2-a]indol-1-one (252 mg, 0.67 mmol) in 75 ml of benzene was treated with 5 mg of sodium hydride and methyl isocyanate (0.1 ml, 1.62 mmol) and stirred at room temperature for one hour. The mixture was quenched with water and the organic layer was separated, dried and concentrated to give 232 mg of the title compound as an off-white solid. The solid was recrystallized from ethyl acetate to give a white powder, mp. 148°-150° C.; Anal. Calc. for C 26 H 29 N 3 O: C, 72.36; H, 6.77; N, 9.74; Found: C, 72.41; H, 6.67; N, 9.67.
EXAMPLE 78
1,2,3,4-tetrahydro-5-methoxy-2-[[1-phenylmethyl)-4-piperidinyl]methyene]cyclopent[b]indol-3-one
The title compound was prepared by a method analogous to that described in Example 44, starting from 5 methoxy-1,2,3,4-tetrahydroclopent[b]indol-3-one. m. p. 200°-201° C.; Anal. Calc. for C 25 H 26 N 2 O 2 : C, 75.92; H, 6.88; N, 7.08; Found: C, 76.04; H, 6.52; N, 6.96.
EXAMPLE 79
1,2,3,4tetrahydro-7-methoxy-2-[[1-phenylmethyl)-4-piperidinyl]methylene]cyclopent[b]indol-3-one
The title compound was prepared by a method analogous to that described in Example 44, starting from 7-methoxy-1,2,3,4-tetrahydrocyclopent[b]indol-3-one. m. p. 239.5°-240° C.; Anal. Calc. for C 25 H 26 N 2 O 2 .0.25H 2 O: C, 76.80; H, 6.83; N, 7.16; Found: C, 76.72; H, 6.91; N, 7.01.
EXAMPLE 80
1,2,3,4-tetrahydro-6,7-dimethoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]cyclopent[b]indol-3-one
The title compound was prepared by a method analogous to that described in Example 44, starting from 6,7-dimethoxy-1,2,3,4-tetrahydrocyclopent[b]indol-3-one. mp. 244.5°-245° C.; Anal. Calc. for C 26 H 28 N 2 O 3 .0.5H 2 O: C, 73.39; H, 6.87; N, 6.58; Found: C, 73.65; H, 6.87; N, 6.58.
EXAMPLE 81
1,2,34-tetrahydro-6,7-dimethyl-2-[[1-(phenymethyl)-4-piperidinyl]methylene]cyclopent[b]indol-3 -one
The title compound was prepared by a method analogous to that described in Example 44, starting from 6,7-dimethyl-1,2,3,4-tetrahydrocyclopent[b]indol-3-one. mp. 244°-245° C.; Anal. calc. for C 26 H 28 N 2 O: C, 81.21; H, 7.34; N, 7.29; Found: C, 81.20; H, 7.19; N, 7.26.
EXAMPLE 82
1,2,3,4-tetrahydro-5-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]cyclopent[b]indol-3-one
The title compound was prepared by a method analogous to that described in Example 47, starting from the title compound of Example 78, mp. 179°-180° C.; 1 H NMR (CDCl 3 )δ 1.21-1.47, 1.66-1.78 (m, 2H), 1.91-2.11 (m, 3H), 2.72 (dd, 1H), 2.89-2.95 (m, 2H), 3.04-3.06 (m, 1H), 3.25 (dd, 1H), 3.51 (s, 2H), 3.94 (s, 3H), 6.78 (d, 1H), 7.08 (t,1H), 7.22-7.31 (m, 6H), 8.87 (s, 1H) ppm.
EXAMPLE 83
1,2,3,4-tetrahydro-7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]cyclopent[b]indol-3-one
The title compound was prepared by a method analogous to that described in Example 47, starting from, the title compound of Example 80, mp. 213°-214° C.; Anal. Calc. for C 26 H 28 N 2 O 2 : C, 77.29; H, 7.26; N, 7.21; Found: C, 76.73; H, 7.19; N, 7.26.
EXAMPLE 84
1,2,3,4-tetrahydro-6,7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]cyclopent[b]indol-3-one
The title compound was prepared by a method analogous to that described in Example 47, starting from the title compound of Example 80, mp. 215.5°-216.5° C.; Anal. Calc. for C 26 H 30 N 2 O 3 : C, 74.61; H, 7.22; N, 6.69; Found: C, 74.42; H, 7.19; N, 6.66.
EXAMPLE 85
1,2,3,4-tetrahydro-6,7-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]cyclopent[b]indol-3-one
The title compound was prepared by a method analogous to that described in Example 47, starting from the title compound of Example 81, mp. 191°-192° C.; 1 H NMR (CDCl)δ 1.38-1.54 (m, 4H), 1.68-1.80 (m, 2H), 1.93-2.05 (m, 3H), 2.35 (s, 3H), 2.38 (s, 3H), 2.70 (d, 1H), 2.87-2.94 (m, 2H), 3.05-3.08 (m, 1H), 3.25 (dd, 1H), 3.52 (s, 2H), 7.20-7.33 (m, 6H), 7.41 (s, 1H), 9.56 (s, 1H) ppm.
EXAMPLE 86
1,2,3,4-tetrahydro-6-hydroxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]cyclopent[b]indol-3-one
A mixture of 1,2,3,4-tetrahydro-6-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]cyclopent[b]indol-3-one (200 mg, 0.51 mmol) and 48% HBr (30 ml) was heated to 110° C. for 3.5 hours. The reaction mixture was allowed to cool and saturated sodium bicarbonate was added until pH 8. The mixture obtained was filtered and the aqueous filrate was extracted with ethanol and the resulting mixture was filtered. Aqueous Na 2 S 2 O 4 was added to the ethanolic filtrate and the light brown solution obtained was concentrated. The residue was partitioned between water and boiling ethyl acetate. The organic layer was combined and washed with water, brine, dried, filtered and concentrated. The residue was purified through silica gel column chromatography to give the title compound as a yellow solid (100 mg). The material was recrystallized from ethanol to give a pale yellow solid, mp. 250°-252° C.; Anal. Calc. for C 24 H 26 N 2 O 2 .0.25H 2 O: C, 76.06; H, 7.05; N, 7.39; ound: C, 76.27; H, 6.67; N, 7.36.
EXAMPLE 87
2,3-dihydro-6-methoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]cyclopent[b]benzofuran-1-one
A mixture of 10% pd/c (110 mg., 0.104 mmol) and the title compound of Example 58 in 1% conc. HCL/EtOH (v/v, 70 ml) was hydrogenated in Parr Shaker at 50 psi for 11 hours. The reaction mixture was filtered through a Celite (trademark) pad. The filtrate was concentrated and the residue obtained was dissolved in EtoAC. The organic layer was washed with 10% NaOH, brine, dried, filtered, and concentrated. The residue was purified by silica gel chromatography (25% MeOH in CH 2 Cl 2 ) to give the title compound (260 mg, 64%) as an off-white solid. Recrystallization (ZtoAC-hexane) of a sample gave a white solid, mp. 137°-138° C.; Anal. Calc. for C 25 H 27 NO 3 1/4 H 2 O: C 76.21; H, 7.03; N, 3.55; Found: C, 74.42; H, 7.19; N, 6.66.
EXAMPLE 88
1,2,3,8-tetrahydro-cyopent[a]indene-1-one
A solution of 3-indenepropionic acid (1.11 g, 5.9 mmol) in 100 ml of benzene was treated with PCl 5 (1.390 g, 6.67 mmol) and the mixture was stirred at room temperature for 2.5 hr. The reaction mixture was cooled at 0° C. and treated with a solution of stannic chloride (4.452 g, 3.97 mmol) in 50 ml of benzene. The resulting mixture was stirred at room temperature overnight and poured over cold dilure HCl and extrated with chloroform. The organic layer was washed with water, dried and concentrated to give 0.841 g (84% yield) of the title compound as a yellow solid 1H NMR (CDCl 3 )δ 2.96(m,4H), 3.5(t,2H), 7.4(m,2H), 7.6(m,2H)ppm.
EXAMPLE 89
1,2,3,8-tetrahydro-2-[[1-phenylmethyl)-4-piperidinyl]methylene]-cyclopent[a]indene-1-one
A solution of 1,2,3,8-tetrahydro-cylcopent[a]indene-1-one (0.838 g, 4.92 mmol) in 50 ml of THF was treated with NaH (200 mg, 5 mmol) at 0° C. and stirred for 3 min. A solution of 1-benzylpiperidine-4-carboxaldehyde (1.100 g, 5.41 mmol) in 5 ml of THF was added at 0° C. After addition, the mixture was stirred at room temperature for 30 min and quenched with 10 ml of methanol, then 10 ml of water. The resulting mixture was quenched with brine and extracted with chloroform. The organic layer was dried and concentrated to column chromatography using chloroform as eluent to give the title compound as a yellow solid. The solid was recrystallized from ethanol to give crystals, mp. 141°-142° C. (decomp.). 1 H NMR (CDCl 3 )δ 1.5-1.8 (m, 4H), 2.1-2.3 (m, 2H), 2.8-3.1(m,6H), 3.5(s,2H), 3.6-3.8(m, 1H), 6.6(d, 1H), 7.2-7.4(m,7H), 7.5(d,1H), 7.7(d,1H)ppm.
EXAMPLE 90
1,2,3,8-tetrahydro-2-[[1-phenylmethyl)-4-piperidinyl]methyl]cyclopent[a]indene-1-one
The title compound of example 89 (456 mg, 1.28 mmol) in 75 ml of ethyl acetate was treated with PtO 2 (45 mg) and hydrogenated at atmospheric pressure for 5 hr. The mixture was filtered through celite and the filtrate was concentrated to give an oil which was purified through silica gel column chromatography to give the title compound as a yellow oil. 1 H NMR (CDCl 3 )δ 1.2-1.4 (m, 2H), 1.4-1.85(m,5H), 1.85-2.2(m,3H), 2.8-3.0(m,6H), 3.53(s,2H), 3.7-3.8(m, 1H), 7.2-7.6(m,9H) ppm.
EXAMPLE 91
ethyl 3-[[1-(phenylmethyl)-4-piperidinyl]ethylamino]methyl-5-chloro-indole-2-carboxylate
The title compound was prepared by the method analogous to that described in Example 66, starting from ethyl 3-formyl-5-chloro-indole-2-carboxylate. 1 H NMR (CDCl 3 )δ 1.4(t,3H), 1.2-1.8(m,7H), 1.8-2.0(m,2H), 2.67(t,2H), 2.8-3.0(m,2H), 3.5(s,2h), 4.2(s,2H), 4.42(q,2H), 7.2-7.45(m,7H), 7.75 (s, 1H) ppm.
EXAMPLE 92
3-[[1-(phenylmethyl)-4-piperidinylethlamino]methyl-5-chloro-indole-2-carboxylic acid
The title compound was prepared by hydrolysis of ethyl 3-[[1-(phenylmethyl)-4-piperidinyl]ethylamino]methyl-5-chloro-indole-2-carboxylate by the method analogous to that described in Example 69. 1 H NMR (DMSO-d 6 )δ 1.0-1.7(m,7H), 1.8-2.0(m,2H), 2.7-3.0(m,4H), 3.4(s,2H), 4.3(s,2H), 7.1-7.4(m,7H), 7.75(s,1H) ppm.
EXAMPLE 93
1,4-dihydro-7-chloro-2-[2[-phenylmethyl)-4-piperidinyl]ethyl]pyrrolo[3,4-b]indol-3(2H)-one
The title compound was prepared by the method analogous to that described in Example 72, starting from 3-[[1-phenylmethyl)-4-piperidinyl]ethylamino]methyl-5-chloro-indole-2-carboxylic acid. Anal. calc. for C 24 H 26 N 3 OCl: C, 70.66; H, 6.43; N, 10.30; found: C, 70.50; H, 6.57; N, 10.24.
EXAMPLE 94
3-[[1-(phenlmethyl)-4-piperidinyl]ethylamino]methyl-5-methyl-benzo[b]thieno-2-carboxylic acid
A mixture of 3-formyl-5-methyl-benzo[b]thieno-2-carboxylic acid (1.03 g, 4.68 mmol) and 1-phenylmethyl-4-(2-aminoethyl)-piperidine (1.235 g, 5.66mmol) was dissolved in 20 ml of ethanol and 10 ml of THF. The resulting mixture was treated with anhydrous sodium acetate (1.16 g, 14.1 mmol), sodium cyanoborohydride (0.593 g, 9.44 mmol) and anhydrous sodium sulfate (3.300 g) and stirred at room temperature overnight. The reaction mixture was filtered through celite, washed with ethyl acetate. The filtrate was concentrated to dryness. The residue was dissolved in ethyl acetate and water. The organic layer was separated, washed with acid, brine, dried, filtered, and concentrated to give the title compound as a yellow solid which was used directly for the next reaction.
EXAMPLE 95
3-[[1-(phenylmethyl)-4-piperidinyl]ethylamino]methyl-6-methyl-benzo[b]thieno-2-carboxylic acid
The title compound was prepared by the method analogous to that described in Example 94, starting from 3-formyl-6-methyl-benzo[b]thieno-2-carboxylic acid (1.44 g, 6.54 mmol), 1-phenylmethyl-4-(2-aminoethyl)-piperidine (1.71 g, 7.84 mmol), sodium cyanoborohydride (0.820 g, 13.08 mmol), sodium acetate (0.540 g. 6.54 mmol) and sodium sulfate in ethanol.
EXAMPLE 96
3-[[1-(phenylmethy)-4-piperidinyl]ethylamino]methyl-5-chloro-benzo[b]thieno-2-carboxylic acid
The title compound was prepared by the method analogous to that described in Example 94, starting from 3-formyl-5-chloro-benzo[b]thieno-2-carboxylic acid (1.000 g, 4.54 mmol), 1-phenylmethyl-4-(2-aminoethyl)-piperidine (1.200 g, 5.50 mmol), sodium cyanoborohydride (0.570 g, 9.07 mmol), sodium acetate (0.450 g, 5.49 mmol) and sodium sulfate in 25 ml of ethanol and 5 ml of dry THF.
EXAMPLE 97
1,2-dihydro-7-methyl-2-[2-[1-phenylmethyl)-4-piperidinyl]ethyl]pyrrolo[3,4-(benzo[b]thieno)-1H-3-one
A mixture of 3-[[1-(phenylmethyl)-4-piperidinyl]ethylamino]methyl-5-methyl-benzo[b]thieno-2-carboxylic acid (1.000 g, 2.37 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.544 g, 2.84 mmol), dimethylaminopyridine (0.059 g, 0.48 mmol), and N-methylmorpholine (0.239 g, 2.36 mmol) in 12 ml of DMF was stirred at room temperature overnight. The mixture was quenched with water and extracted with ethyl acetate. The organic layer was dried, filtered, and concentrated to give 0.815 g of the crude material as a yellow oil. The yellow oil was purified through silica gel column chromatography using 10% methanol in chloroform as eluent to give the title compound as a pale oil. 1 H NMR (CDCl 3 )δ 1.15-1.45(m,3H), 1.5-1.8(m,4H), 1.8-2.0(m,2H), 2.47(s,3H), 2.75-2.9(m,2H), 3.45(s,2H), 3.6(t,2H), 4.4(s,2H), 7.1-7.35(m,6H), 7.5(s, 1H), 7.75(d,1H) ppm.
EXAMPLE 98
1,2-dihydro-6-methyl-2-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]pyrrolo[3,4-b](benzo[b]thieno) 1H-3-one
The title compound was prepared by the method analogous to that described in Example 97, starting from 3-[[1-phenylmethyl)-4 -piperidinyl]ethylamino]methyl-6-methylbenzo[b]thieno-2-carboxylic acid to give the title compound as a yellow glass; 1 H NMR (CDCl 3 )δ 1.2-1.4 (m, 3H), 1.5-1.8 (m, 4H), 1.8-2.0 (m, 2H), 2.46 (s, 3H), 1.8-2.0 (m, 2H), 3.5(s,2H), 3.6(t,2H), 4.4(s,2H), 7.1-7.4(m,6H), 7.58 (s, 1H), 7.64 (s, 1H) ppm.
EXAMPLE 99
1,2-dihydro-7-chloro-2-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]pyrrolo[3,4-benzo[b]thieno) 1H-3-one
The title compound was prepared by the method analogous to that described in Example 97, starting from 3[[1-(phenylmethyl)-4-piperidinyl]ethylamino]methyl-5-chlorobenzo[b]thieno-2-carboxylic acid to give the title compound as pale solid; 1 H NMR (CDCl 3 )δ 1.2-1.4(m, 3H), 1.6-1.8(m,4H), 1.8-2.05(m,2H), 2.8-3.0(m,2H), 3.5(s,2H), 3.68(t,2H), 4.5(s,2H), 7.2-7.4(m,5H), 7.42(dd, 1H), 7.74(d, 1H), 7.84(d,1H) ppm.
EXAMPLE 100
2,3-dihydro-5-methyl-1H-cyclopent[b]benzo[b]thieno)-1-one
A solution of 5-methyl-benzo[b]thieno-3-propionic acid (0.974 g, 4.43 mmol) in 100 ml of toluene was treated with PCl 5 (1.013 g, 4.87 mmol) and the resulting mixture was stirred at room temperature for 3 hr. The reaction mixture was cooled to 0° C. and SnCl 4 (3.36 g, 17.72 mmol) was added and the mixture was stirred at room temperature overnight. The mixture was quenched with dilute HCl and extracted with chloroform. The organic layer was separated, dried and concentrated to give purple solid which was triturated with di-isopropyl ether to give the tile compound as a purple crystals (615 mg). The crystals was decolorized with Darco and recystallized from ethyl acetate to give colorless crystals; mp 189.5°-190° C.; Anal. calc. for C 12 H 10 SO: C, 71.26; H, 4.98; found: C, 71.05; H, 4.72.
EXAMPLE 101
2,3-dihydro-5-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-cyclopent[b](benzo[b]thieno)-1-one
A solution of 2,3-dihydro-5-methyl-1H-cyclopent[b](benzo[b]thieno)-1-one (350 mg, 1.73 mmol) in 30 ml of dry THF was treated with sodium hydride (71 mg, 1.77 mmol) at 15° C. After 3 min, a solution of 1-benzylpiperidine-4-carboxaldehyde (406 mg, 2.0 mmol) in 5 ml of dry THF was added and stirred at 15° C. for 30 min. The mixture was quenched with water and extracted with ethyl acetate. The organic layer was dried and concentrated to give a brown solid which was recrystallized from ethyl acetate to give the title compound as white crystals; mp 192°-193.5° C. (decomp.). Anal. calc. for C 25 H 25 NOS. 0.3 H 2 O: C, 76.42; H, 6.57; N 3.56; found C, 76.30; H, 6.22; N, 3.62.
EXAMPLE 102
2 3-dihydro-5-methyl-2-[[1-phenylmethyl]-4-piperidinyl] methy]-1H-cyclopent[b](benzo[b]thieno)-1-one
A solution of 2,3-dihydro-5-methyl-2-[[1-(phenylmethyl)-4-piperidinyl]methylene]-1H-cyclopent[b](benzo[b]thieno)-1-one (300 mg) in 100 ml of ethanol and 100 ml of ethyl acetate was treated with PtO 2 (30 mg) and hydrogenated at 42 psi for 1 hr (the reaction is not done). An additional PtO 2 (70 mg) was added and the mixture was hydrogenated for 2hrs. The mixture was filtered through celite and the filtrate was concentrated to dryness to give 267 mg of yellow solid. The solid was purified through silica gel chromatotron using chloroform in chloroform as eluent to give 133 mg of the title compound as a white solid. The solid was recrystallized from ethyl acetate to give a colorless needle. Anal. calc. for C 25 H 27 NOS. 0.1 H 2 O: C, 76.76; H, 6.96; N, 3.58; found: C, 76.63; H, 7.00; N, 3.78. | Compounds of the formula ##STR1## wherein ring A, ring B, ring D, R 2 , R 3 , R 4 , R 5 , R 6 ,R 11 , R 12 , R 13 , E, G, X and P are as defined below. The compounds of formula I are cholinesterase inhibitors and are useful in enhancing memory in patients suffering from dementia and Alzheimer's disease. | 2 |
TECHNICAL FIELD OF THE INVENTION
The present invention relates to automotive anti-theft system equipment and, more specifically, relates to an apparatus and method for random problem simulation.
BACKGROUND OF THE INVENTION
There are many techniques in use to attempt to prevent unauthorized automobile use or theft. These techniques range from simple kill switches to elaborate computer controlled alarm and disabling systems. However, professional thieves study to be proficient at defeating the entire range of anti-theft techniques.
The simplest forms are the easiest to defeat. Keys can be reproduced and locks can be picked, or the thief can hot-wire the ignition system. If a hidden kill switch has been installed, it can also be located and easily bypassed. Hidden kill switches do not usually remain hidden long, due to mechanics and other users of the vehicle being told of the secret location.
At one time audible alarm systems were effective deterrents. This is no longer true because most people are conditioned to false alarms and simply ignore the audible alarms. Thieves recognize this and are no longer deterred. They know how to defeat the audible alarm before anyone becomes concerned. This type of system is only effective when the vehicle owner personally hears the alarm.
Vehicle disabling systems, such as fuel cutoff valves or ignition shut down circuits, are better alternatives. A professional thief can, however, defeat these types of systems. Most of these systems are very repeatable, and therefore become obvious to the thief. Once a thief is aware of the system, he can take appropriate action to defeat it.
Most theft deterrent systems have limited effectiveness. They are usually detectable and defeatable by a proficient thief. To be effective, a proper problem simulation system should be undetectable by the thief. It would appear to be a typical automotive problem, possessing related symptoms that recur unpredictably. It should also employ multiple symptoms related to a specific problem in a random fashion with each symptom having an associated probability of taking place. Each of the random symptoms should exist for some random duration of time before the next symptom, if any can occur.
PRIOR ART
As discussed in the background there are a number of methods to protect a motor vehicle against theft. Few of the many automotive theft-prevention patents detail allowing a vehicle to start and temporarily run before disabling a critical component, such as the fuel or ignition system.
U.S. Pat. No 5,486,806 describes a fuel flow restricting system. It allows the vehicle to run for a predetermined period of time, after which fuel flow is restricted to a small amount that limits the power the engine can provide. This is somewhat effective, but the time duration is very repeatable, which is a clue to the existence of a theft deterrent device.
An ignition disabler is described in U.S. Pat. No. 4,992,670. It allows the engine to start successfully, but disables it when the keyswitch is returned from the START position to the RUN position. This also confuses the thief initially, but the obvious pattern could be noticed and the device discovered.
In U.S. Pat. No. 5,463,372 the engine is allowed to run for a short period of time. An oscillating relay at a fixed frequency is used to interrupt the ignition system or EFI (Electronic Fuel Injection) system causing partial disablement. The time duration of this effect is adjustable by a variable resistor. This variation is set by the user and goes unnoticed by the thief. Once this sequence completes, total shutdown occurs and leaves the vehicle impaired for future start attempts. This system does not exhibit repeatable behavior. However, it is obviously not random due to the fact that it only occurs after the initial attempt to start the vehicle.
Described in U.S. Pat. No. 5,473,200 is a device that consists of a central control unit and one or more remote devices. The remote device(s) are configured such that they time out after a preset time-out period, unless they receive a signal from the central control unit. These remote receivers are on/off type devices with no random characteristics. This type of shut down sequence is not very confusing and the system could possibly be overcome by the thief.
U.S. Pat. No. 4,452,197 counts spark pulses of the ignition system. It can be configured to simply count a predetermined number of pulses, and then disable the vehicle. Optionally it can also intersperse alternating periods of spark inhibition and enablement to produce an illusion of engine misfiring before disablement. These periods are of a variable time duration that is defined by counting a fixed number of variable frequency spark pulses from the ignition control signal. Once again this variation is also set by the user and goes unnoticed by the thief. In either configuration, this system will produce a repetitive pattern that can be recognized by a potential thief.
The present state of the art does not exhibit random characteristics, and this is essential for properly simulating automotive problems. Most of the prior art is cyclic in nature but all have some form of repetition that could be detected by a knowledgeable thief. Once the device is detected, it becomes much more likely that the thief will locate and defeat it, gaining access to the "protected" vehicle. There is much less chance of this occurring if confusion is created by the device exhibiting random characteristics. A problem simulation system possessing random characteristics would appear to be very natural compared to most real life vehicle engine problems.
SUMMARY OF THE INVENTION
The present invention is a theft deterrent system that simulates problems in motor vehicles. Most vehicle problems are erratic and unpredictable, exhibiting random characteristics with no recognizable patterns. On engine startup, this device allows normal engine operation for a random time duration (greater than a predetermined minimum time) during which it can be deactivated. If it is not deactivated, it produces random problem simulation with random, erratic, and unpredictable effects similar to those of actual automotive ignition and fuel system problems. The device is not an alarm system, but can function well in conjunction with any alarm device. If a separate alarm is also on the vehicle, the two will function as backups to each other.
This system consists of several components coupled with motor vehicle subsystems. The heart of the system is the controller which supervises the entire system, communicating with one or more remote disabling receivers, which act as the interface circuitry between the controller and the motor vehicle subsystem. The controller performs verification of operator identification in addition to generation of random control information signals. A variety of methods can be used to generate the random control information signals, including receiving a radio frequency, using digital logic components, or programming a micro-controller, in order to provide a random control information signal. The functionality of the controller is based on the ignition keyswitch and anti-hijacking inputs, in addition to an input circuit. The keyswitch input simply monitors the switched battery voltage of the vehicle. The anti-hijacking button is mounted in a concealed convenient location. The input circuit could be a variety of devices, including a keypad, a voice recognition circuit, a magnetic strip, or any other common personal identification devices. A hard-wired keypad can be mounted in a convenient location (possibly hidden from view) to read in the access code. A remote keypad may also be attached to any convenient personal object and would function the same as the hard-wired keypad, in that an access code could be required rather than a single push-button enable/disable. The input circuitry could also generate a security code to accompany the operator identification. The controller would then require that the correct security code was present before allowing operator authorization. The remote disabling receivers (interface circuits) can be linked to the controller through a variety of methods, including infrared light, hard-wiring, radio frequency transmission, or any other electromagnetic connection. The disabling receivers could use either unidirectional or bidirectional communications, and be linked to the controller individually or through a common wiring bus. The controller could also generate a security code to accompany the random control information signal. The interface circuit would then require that the correct security code was present before allowing vehicle subsystem operation. The output of the remote disabling receivers are wired in series with the individual vehicle subsystems to be disabled. By disabling more than one subsystem of the vehicle, it can still be protected if by chance one of the disabling receivers is located and defeated. These receivers act as normally open switching devices that are controlled by the system controller. If power is removed from any part of this system, the vehicle will be inoperative.
When the vehicle is started, the device allows normal engine operation for some predetermined minimum time in addition to a random time period. If valid operator identification is entered during this time, the device continues to allow normal engine operation indefinitely. This is confirmed by an audible signal. Otherwise it repetitively randomly determines a symptomatic mode to exhibit until a reset signal is detected or a variable duration time-out has elapsed. The symptomatic modes consist of the signal types of run, stutter, severely impaired, and off. The run mode consists of a random (not exceeding a predetermined maximum) duration period of normal engine operation. This mode occurs very seldomly after initial startup. The stutter mode consists of very rough engine operation and significantly decreased horsepower. The duration and specific timing of this sequence are both random. The severely impaired mode consists of a random duration period which severely impairs the engine beyond the ability to continue running, yet still exhibiting signs of potential operation with random characteristics. This prevents the engine from running yet makes the problem hard to diagnose. The off mode completely disables the vehicle subsystem under control for a random time duration. If an attempt is made to restart the vehicle (with or without first switching the key off) the device will continue to randomly determine which of the symptomatic modes to exhibit. By creating so many random elements there is no chance for a pattern to develop, and therefore very little possibility that the device will be recognized by an unauthorized operator.
An added feature is programming mode, which allows the programming of a user access code. Within a predetermined time after the system has been enabled, the owner can use the keypad to optionally change the user access code. This feature is useful to ensure the master access code remains confidential. A temporary change of the user access code can secure against mechanics or other temporary users of the vehicle. A simple code change afterward regains total security.
Another feature is the valet mode. During this mode of operation the valet attendant has a limited number of start attempts and sufficient time in each to allow for parking or returning the vehicle. Upon return of the vehicle the owner can simply exit valet mode and return to a fully enabled state. If a timeout period elapses in any start attempt during valet mode, the vehicle begins the problem simulation mode of operation.
An anti-hijacking mode is included, which allows an anti-hijacking button hidden under the carpet to inform the controller that the vehicle has been hijacked. When this button has been pressed normal engine operation continues for a short period of time, after which the problem simulation mode is entered. This allows the thief a short getaway to keep him/her a safe distance from the owner.
This system allows flexibility in that the user can define a custom implementation by locating disabling receivers on any one or more vital vehicle subsystem(s). This means that every system becomes unique, and thieves are faced with unknowns on every vehicle with this device. This, in addition to the random nature of the device, results in a highly secured vehicle protection system.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A illustrates a block diagram of a minimal system configuration using an infrared transmitter and receiver to implement stutter/enabled vehicle subsystem control and shows component placement within the vehicle.
FIG. 1B illustrates a block diagram of a minimal system configuration using a hard wired receiver to implement stutter/enabled vehicle subsystem control and shows component placement within the vehicle.
FIG. 1C illustrates a block diagram of a more expanded system configuration including two different types of vehicle subsystem control (both stuttered and switched) using a combination of both hard wired and infrared receivers.
FIG. 2A depicts a typical electronic ignition system.
FIG. 2B depicts a typical electronic ignition system modified with the present invention.
FIG. 2C depicts a typical electronic fuel injection system.
FIG. 2D depicts a typical electronic fuel injection system modified with the present invention.
FIG. 2E depicts a typical electronic fuel pump system.
FIG. 2F depicts a typical electronic fuel pump system modified with the present invention.
FIG. 3 shows a schematic diagram of the system controller and associated user input devices.
FIG. 4A shows a schematic diagram of an infrared receiver.
FIG. 4B shows a schematic diagram of a hard wired receiver.
FIG. 5A depicts a possible timing diagram for the problem simulation stuttered signal used in the system.
FIG. 5B depicts a possible timing diagram for the problem simulation switched signal used in the system.
FIG. 5C depicts the timing diagram for the enabled signal used in the system.
FIG. 6A is a top level flow chart of the system software showing an overview of the code execution sequence.
FIG. 6B is an expansion of the top level flow chart detailing the entities for enablement.
FIG. 6C is an expansion of the top level flow chart detailing the processing of the user features.
FIG. 6D is an expansion of the top level flow chart detailing the random problem simulation loop sequence.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1A depicts a block diagram of a minimal system configuration for the present invention. The system controller 100, located in the interior of the motor vehicle 105, is connected to vehicle battery voltage 110 through fuse 115. The controller 100 monitors inputs from the vehicle ignition switch 120, an anti-hijacking button 125, and a numeric keypad 130, and possibly a wireless remote keypad 135. The controller 100 outputs a signal on output group 140 which is either a stuttered or enabled signal, depending on the state of the device. The signal is then transmitted by the infrared transmitter 145. This transmitted signal is then received by an infrared receiver 150 which is connected in series with a vital vehicle subsystem, such as the ignition system 155 depicted in FIGS. 2A and 2B, the fuel injection system 156 depicted in FIGS. 2C and 2D, or the fuel pump system 157 depicted in FIGS. 2E and 2F. Shown in FIG. 1B is a similar system modified from FIG. 1A excluding the infrared transmitter 145 and replacing the infrared receiver 150 with a wired receiver 160 connected directly between the controller 100 and a vital vehicle subsystem. FIG. 1C displays a more expanded block diagram of said system in FIGS. 1A and 1B. FIG. 1C includes multiple receivers, both wired 160 and infrared 150, each connected in series with an associated vehicle subsystem component and receiving a signal from either output group 140 or output group 165 from the controller 100. As stated earlier, the signal on output group 140 is either a stuttered or enabled signal, depending on the state of the device. Similarly, the signal on output group 165 is either a switched or enabled signal, depending on the state of the device. The type of vehicle subsystem under control determines which type of signal output should be connected through each receiver. The signal of output group 140 could be connected to any low power vehicle subsystem component such as an ignition pickup coil as depicted in FIGS. 2A and 2B, an ignition coil, a crank sensor, any other source of ignition sync pulses, fuel injectors as depicted in FIGS. 2C and 2D, automatic shutdown relays, or various computer signals. The signal of output group 165 could be connected to any other low power vehicle subsystem component including fuel pickup sensors, fuel pumps as depicted in FIGS. 2E and 2F, fuel valves, manifold absolute pressure sensors, or any other automotive computer sensor which would result in impaired engine operation. The system is thereby versatile enough to function well in any configuration with most vehicle subsystems in existence. Expanding the system should be trivial to those skilled in the art, however, for the purposes of this description, the focus will be on controlling a single subsystem.
The battery voltage 110 is connected through fuse 115 to the power supply section 170 of the controller 100 circuit schematic diagram exhibited in FIG. 3. The power supply 170 consists of a filter capacitor C1 connected to the input of a 5 volt monolithic regulator U2. Capacitor C2 serves to filter the 5 volt output of regulator U2. This provides the regulated 5 volt supply for the controller 100 circuitry. Supply voltage monitor U3, resistor R1, and capacitor C3 comprise a reset circuit that ensures proper operating voltage for the microcontroller U1.
The microcontroller U1 is a PIC16C71 single-chip device which contains a microprocessor, random access memory (RAM), electronically programmable read only memory (EPROM), analog to digital converters, and digital input/output circuitry, therefore little external support circuitry is necessary. Crystal Y1 in addition to capacitors C7 and C8 provide the necessary oscillator circuit for the microcontroller U1. If the device becomes enabled (which will be defined in detail later) then a digital output pin is driven to a logic high level. This logic high is coupled through diode D1 and resistor R6 to charge a time delay circuit defined by capacitor C6 and resistor R7. The output of the time delay circuit returns to an analog input pin on microcontroller U1 through resistor R8. This circuitry allows the microcontroller to continue an enabled state of operation if any short duration glitch occurs and causes a system reset. Glitch detection occurs at the time of power up by the microcontroller U1 reading the amount of charge on the time delay circuit consisting of capacitor C6 and resistor R7. If the amount of charge on capacitor C6 is above a predetermined value then microcontroller U1 re-enables itself to its previous state.
Resistor R3 pulls an input pin on the microcontroller U1 to a logic low level while the vehicle ignition switch 120 is in the OFF position. While in the ON position, the vehicle ignition switch 120 pulls the pin to a logic high level through resistor R2 informing the microcontroller U1 that operation of the vehicle is being attempted. The numeric keypad section 130 comprises a set of five normally open push-buttons, S1 through S5. They are all connected through resistor R9 to the regulated 5 volt supply and to the microcontroller U1 through a resistive ladder network consisting of resistors R10 through R14. For each individual push-button pressed, this produces a unique voltage on an analog input pin of microcontroller U1, allowing the interpretation of various system control codes. Control codes such as valet mode, programming mode, and operator identification are confirmed to the operator by audible beeps, generated by microcontroller U1 outputting a 3 kilohertz square wave through resistor R5 and into buzzer BZ1.
The microcontroller U1 is capable of generating multiple random control information signals to control the various vehicle subsystems. There are several output pins for this, which are divided into two separate groups. If the device has been enabled, both groups output an enabled signal 210 of FIG. 5C. If the device has not been enabled, problem simulation occurs and both groups output their respective signals. One set of pins, output group 140, outputs a complex waveform called the stuttered signal 200 of FIG. 5A. The other set of pins, output group 165, outputs a signal derived from the stuttered signal 200 which is called the switched signal 205 of FIG. 5B. These two signals will be described in more detail later. These signals are each communicated through current limiting resistors R15 through R20 and coupled to the interface circuit through terminal connections T1 through T6. The interface circuit consists of either directly connecting to the wired receiver 160 or to an infrared transmitter 145 which transmits the random control information signal to the infrared receiver 150. The infrared transmitter 145 passes the signal through LED D5 to be transmitted via infrared light to the infrared receiver 150. If the device is in the enabled state, microcontroller U1 monitors the anti-hijacking circuitry, which consists of push-button S6. This anti-hijacking input is pulled to a logic high level by resistor R4, and pulled to a logic low level if push-button S6 is depressed. The depression of push-button S6 allows the vehicle operator to inform the microcontroller U1 that a hijacking has occurred.
FIG. 5A through 5C depict the waveforms of the random control information signals, the stuttered signal 200, the switched signal 205, and the enabled signal 210. These provide the means for communication between the controller 100 and various receivers, either infrared 150 or wired 160. The stuttered signal 200 of FIG. 5A can be transmitted on output group 140, and is composed of random control information 200A modulated by a 3 kHz frequency and modulated again by a 40 kHz frequency. The random control information 200A consists of several signal types randomly arranged in order to produce the problem simulation effects in the vehicle subsystem. These signal types are run 215, stutter 220, severely impaired 225, and off 230 which correspond to the symptomatic modes of random duration mentioned in the summary. The run signal type 215 is simply a continuous logic high signal for the chosen duration. The stutter signal type 220 consists of two states which follow each other in a repetitive order for a random number of cycles. The first state is of random duration during which the signal is always in a logic high state. The second state is also of random duration during which the signal is switched to a logic high state for 25 milliseconds and a logic low state for 50 milliseconds repeatedly. The severely impaired signal type 225 is defined as the signal being switched to a logic high state for 25 milliseconds and then a logic low state for 175 milliseconds repeatedly for the chosen duration. The off signal type 230 is simply a continuous logic low signal for the chosen duration. Before the random control information 200A is actually communicated to the receivers it is modulated by a 3 kHz frequency. The resulting modulated signal is depicted as 200B, which has been magnified from 200A. This signal 200B is modulated again by a 40 kHz frequency. This modulation is depicted as 200C, which has been magnified again from 200B. The result of the random control information 200A modulated by both the 3 kHz and 40 kHz frequencies is the actual stuttered signal 200 that is communicated on the output group 140 to control the vehicle subsystem. The switched signal 205 of FIG. 5B can be communicated on output group 165, and is similarly composed of random control information 205A modulated by a 3 kHz frequency and modulated again by a 40 kHz frequency. The random control information 205A is derived from the stuttered signal's random control information 200A. Any time the stuttered signal's control information 200A exhibits the run signal type 215, the switched signal's control information 205A will also exhibit a run signal type 215. During any other signal type of the stuttered signal's control information 200A, the switched signal's control information 205A will exhibit an off signal type 230. Just as in the case of the stuttered signal 200, the random control information 205A is modulated by a 3 kHz frequency and magnified in 205B. This signal 205B is modulated again by a 40 kHz frequency and magnified in 205C. The result of the random control information 205A modulated by both the 3 kHz and 40 kHz frequencies is the actual switched signal 205 that is communicated on the output group 165 to control the vehicle subsystem. The enabled signal 210 of FIG. 5C can be communicated on both output groups 140 and 165, and is simply composed of a logic high signal as the control information 210A modulated by a 3 kHz frequency and magnified in 210B. This signal 210B is modulated again by a 40 kHz frequency and magnified in 210C.
The infrared receiver 150, shown in FIG. 4A, consists of an infrared module U5 which receives infrared signal information from the infrared transmitter 145. The infrared module U5 is powered by a 5 volt supply consisting of resistor R23 connected between vehicle battery voltage 110 and zener diode D3. The received infrared signal information depends on the wiring connections with the controller, and can be any one of either the stuttered signal 200 of FIG. 5A, the switched signal 205 of FIG. 5B, the enabled signal 210 of FIG. 5C, or no signal. The 40 kHz frequency contained in these signals is necessary in order for the infrared module U5 to pass any signal. The infrared module U5 removes the 40 kHz frequency and passes the remaining 3 kHz frequency and control information signal to capacitor C10. In the wired receiver 160, shown in FIG. 4B, capacitor C10 is connected through wiring directly to any one of terminals T1 through T6 of the controller 100 depicted in FIG. 3 and therefore still contains the 40 kHz frequency. From capacitor C10 the remaining circuitry of FIGS. 4A and 4B is the same for both the wired receiver 160 and the infrared receiver 150. In both circuits, capacitor C10 passes only pulsating signals (like the random control information signals), thereby preventing a bypass connection to either vehicle battery voltage 110 or vehicle ground. In either receiver, the pulsating signal is then passed through diode D2 to resistor R21 and capacitor C11 which provide envelope detection filtering. This filtering effectively removes the 3 kHz frequency, and also the 40 kHz frequency (which would still be present only in the wired receiver) from the signal leaving only the control information. This information passes through resistor R22 to the base of transistor Q1 which switches the solid state relay U4 through current limiting resistor R23, based on the control information. The normally open terminals of the solid state relay U4 are then connected in series with the vehicle subsystem under control, thereby allowing random control of its functionality which impairs the vehicle.
In describing the microcontroller U1 software, references are made to the hardware and timing signals of FIGS. 2 through 5. In order to allow for precise timing of the control signals, a software interrupt routine has been implemented. The interrupt routine occurs every 12.5 microseconds and toggles an output buffer that may or may not be coupled to the microcontroller U1 pins of output groups 140 and 165. Toggling this buffer on for 12.5 microseconds and then off for another 12.5 microseconds generates a 40 kHz squarewave frequency. A 3 kHz frequency is derived from this 40 kHz frequency, and is used to control this toggling of the 40 kHz frequency to the output buffer. This results in a signal in the output buffer which is a 3 kHz frequency modulated by a 40 kHz frequency. Two counters are used throughout the problem simulation code to determine the enabling or disabling of the coupling of the buffer to the output groups 140 and 165. The time periods of these two counters are one fifth of a second and one fortieth of a second. These counters are derived from the specific timing of the interrupt. Every 12.5 microseconds execution of the main line code is briefly interrupted by this routine, therefore no matter what process the main line code is performing, accurate timing is maintained.
A top level view of the microcontroller U1 software is graphically represented in FIG. 6A. Code execution begins with device power up in step 300. This occurs only when battery voltage 110 is applied to the device, such as during installation. Initialization of the code variables and the registers of microcontroller U1 occur next in step 302. Following this, step 304 provides a power up timer which delays device operation for a predetermined time interval. This further frustrates an unauthorized user if the device is located and tampered with. Step 306 begins the looping of the main line code, which is executed repetitively while battery voltage 110 is applied to the device. A new random number is generated every time the loop executes. Every time a random number is generated the previous random value is used as the seed for the new random number, therefore this serves to keep the system more random. After this step 308 checks the vehicle ignition switch 120. If the ignition switch is in the OFF position, the timing interrupt is disabled, and the device enters a sleep state during step 310 in order to conserve battery power. The sleep state relies on an internal watchdog timer to time-out and continue subsequent code execution. At this point the system enters the startup state and the code returns to the beginning of the main loop of step 306. If the ignition switch is in the ON position during step 308, then the device enters step 312, which is detailed in FIG. 6B.
The system is checked to see if the valet mode is active, which is indicated by the valet flag, in step 314. If the device is in the valet mode, then the enabled signal 210 is sent to the output buffers and is coupled to output pin groups 140 and 165 of the controller allowing vehicle subsystem operation in step 316. If the device is not in the valet mode then the vehicle subsystem is not allowed to operate. In either case code execution continues in step 318. The keypad 130 (which is also used as the valet input, and is the only valet circuitry necessary) is scanned for a single keypress and the five most recent keypresses are compared to both the master code (which is factory programmed) and the user code (which is programmed by the user) each time step 318 occurs. If the accumulated keypresses do not match either code, then code execution returns to FIG. 6A at step 326. If the accumulated keypresses match one of the five digit access codes then the system is checked to see if it is already in the enabled state in step 320. If the system is not in the enabled state then step 324 changes the system to the enabled state and confirms authorized operator identification entry to the user by an audible signal. The enabled state allows the enabled signal 210 to be sent to the output buffers and is coupled to output pin groups 140 and 165 of the controller allowing vehicle subsystem operation. All vehicle subsystems remain under enabled control until the vehicle ignition switch 120 is switched to the OFF position. If the system is in the enabled state during step 320 then code execution continues to step 322 where toggling between the valet mode and the enabled state occurs. This occurs anytime the user reenters the access code and is confirmed by an audible signal. The valet mode allows multiple restarts (up to a predetermined maximum) of the vehicle and allows it to operate fully until a predetermined maximum interval of time for each restart has expired, as determined by the valet timer. If this time interval expires during any valet mode operation, no more restarts will be allowed. Toggling back to the enabled state is also confirmed by an audible signal, and will not allow any restarts once the vehicle ignition switch 120 is returned to the OFF position. Once the system state has been toggled, code execution continues on FIG. 6A in step 326.
At this point, step 326 determines whether the system is in the enabled state. If the system is in the enabled state, then processing of the feature states occurs in step 328. This includes processing for the programming mode, the anti-hijacking mode, and the valet mode, and is depicted in detail in FIG. 6C.
During the first five seconds of the enabled state, step 330 allows the device to enter the programming mode upon entry of a predefined key sequence, which allows programming of the temporary user access code. The programming circuitry also consists simply of a programming input, which is also the keypad 130. This option is only available if the master access code was used to enable the system. If the programming mode has been entered (which is indicated by the programming flag), then step 332 checks to see if five keypresses have been recorded. If not, then step 334 attempts to record a keypress each time the main loop scans through this step. If five keypresses have been recorded or a programming mode time-out occurs then step 336 exits the programming mode, leaving the system in the enabled state. Step 338 occurs next regardless of what occurred in steps 330 through 336. The anti-hijacking button 125, which comprises the anti-hijacking circuitry, is checked in step 338. If the anti-hijacking input is pressed, then the device enters the anti-hijacking mode (indicated by the anti-hijacking flag). Once the device is in the anti-hijacking mode step 340 checks the anti-hijacking timer for a predetermined time-out period. If this period has elapsed, then step 342 places the system in the disabled state. Step 344 occurs next regardless of the path through steps 338 through 342. Step 344 checks to see if the device is in the valet mode. If the device is in the valet mode step 346 checks a timer for a predetermined time-out period. If this period has elapsed, then step 348 places the system in the disabled state. Step 354 of FIG. 6A occurs next regardless of the path through steps 344 through 348.
If in step 326 the device was not in the enabled state, then at this point the system must be in the startup state, and step 350 determines if the random startup time has expired. This startup time is of a randomly chosen duration which is longer than a predetermined minimum and shorter than a predetermined maximum. If the startup time has expired, then step 352 switches the system to the disabled state and continues operation at step 354. In step 354 it is determined if the device is in the disabled state. If not, then step 356 insures that the output buffer, which contains the 3 kHz and 40 kHz modulation information, is coupled to the output groups 140 and 165, thereby communicating the enabled signal 210 to the interface circuits. Code execution then returns back to the beginning of the main loop in step 306. If the system is in the disabled state during step 354 then step 358 occurs, resulting in execution of the problem simulation routine, which is detailed in FIG. 6D.
Once the system reaches the disabled state, it remains in this subloop section of code and does not return to the main loop until a time-out or reset sequence occurs. Step 360 determines if the system has been returned to the startup state. If not, then step 362 checks the ignition switch 120. If the switch is still in the ON position, then step 364 generates a random number. Considering this random number and the weights associated with the probability of each occurring, step 366 transfers control to one of steps 368 to 374 for implementation of the problem simulation. If by chance step 368 is chosen, a random number is generated to determine the duration of the run signal type 215, which effectively allows operation of the vehicle subsystems under control. This random duration lies between a predetermined minimum and maximum. If by chance step 370 is chosen, a random number is generated (between a predetermined minimum and maximum) to determine the number of stutter cycles that should occur during the stutter signal type 220. These cycles consist of either a random duration on period or a random duration period of repetitive oscillations consisting of 25 milliseconds on and 50 milliseconds off. This produces the effect of an impaired yet still operational vehicle subsystem, which in the case of the ignition subsystem results in very rough engine operation and significantly decreased horsepower. If by chance step 372 is chosen, a random number is generated (between a predetermined minimum and maximum) to determine the duration of the severely impaired signal type 225. This signal type consists of repetitive oscillations consisting of 25 milliseconds on and 175 milliseconds off. This produces the effect of a severely impaired vehicle subsystem, which in the case of the ignition subsystem results in no engine operation while still exhibiting occasional spark firing to indicate the potential for operation. If by chance step 374 is chosen, a random number is generated to determine the duration of the off signal type 230, which effectively allows no operation of the vehicle subsystems under control. This random duration lies between a predetermined minimum and maximum. Regardless of which problem simulation step occurred in steps 368 through 374, code execution resumes at step 376. This step resets the time-out interval counter that is constantly being updated by the interrupt routine. This ensures that a time-out will not occur until the ignition switch 120 is in the OFF position for the entire duration of the time-out interval. If in step 362 the ignition key 120 is in the OFF position, then control is transferred to step 378 and the time-out interval timer continues counting. Step 378 looks for either a reset sequence from the ignition switch 120 or the expiration of the predetermined time-out interval. This ignition switch reset sequence is defined as three ignition switch 120 ON/OFF cycles within a predetermined time period. If either of these conditions is met, then execution continues at step 380. The device transitions from the disabled state to the startup state and returns to step 360 where the startup state is found to exist, which then exits the problem simulation subloop and returns control to step 306 where the main loop begins again. If in step 378 neither condition is met, then control also returns to step 360 where the startup state is found to not exist, and therefore the problem simulation loop continues. This results in the problem simulation loop randomly chaining together the four problem simulation signal types with random time variations as long as the unauthorized user continues to attempt operation of the vehicle. | An anti-theft vehicle subsystem disabling device including a digital controller and one or more remote receiving vehicle subsystem interface units for randomly simulating problematic vehicle behavior. The system determines user authorization based on keycode entry of either a master code or a programmable user code. Once authorized all vehicle subsystems under control operate normally. While authorized, the system also allows optional entry into a valet mode and constantly monitors a hidden anti-hijacking button. Any time unauthorized use is determined, the digital controller randomly generates a unique controlling signal with random timing variations that is communicated to the remote receiving subsystem interface units. These units can be connected in series with vital vehicle subsystem components in order to interfere with typical subsystem component operation, thereby inducing the illusion of an actual vehicle problem severe enough to inhibit vehicle driveability. This system allows unique implementation by locating disabling receivers on any variety of vital vehicle subsystems, presenting thieves with multiple unknowns specific to each vehicle. Due to this, in addition to the random nature of the device, there is no chance for a pattern to develop, and therefore very little possibility that the device will be recognized by an unauthorized operator. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority of U.S. Provisional Patent Application No. 61/848,549 filed 7 Jan. 2013, which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to the field of construction. More particularly, the present invention relates to installation of construction items, such as windows and doors, into a rough opening.
BACKGROUND OF THE INVENTION
[0003] In the construction trade, it has long been known that items such as window and door jambs require adjustment in order to fit properly within a rough opening framed for such item. Window jambs are typically known to be installed after a window unit is in place, whereas door jambs are typically known to be provided integrated with the door unit. In either instance, the jambs require squaring up within the rough opening. Typically, beveled shims fabricated from split wood such as cedar are placed around the given item (i.e., window or door jamb) during installation and lodged in place between the item's outer edges and the rough opening. This method of “shimming” in order to square up the installed jamb is therefore well known by builders. However, this known method of shimming is inexact, awkward, and time-consuming. Moreover, it can be very difficult to shim up a jamb with precision in this manner.
[0004] Another known technique used by builders is the installation of one or more screws into the rough opening prior to placement of the jamb therein. Such screw(s) are engaged with the rough opening only as far as deemed necessary to provide spacing for the jamb. If adjustments are needed to provide more space or less space for the jamb placement, then the jamb (in the instance of a window) or frame/jamb (in the instance of a door) can be taken out of the rough opening and set aside while the screw(s) are readjusted into or out of the side(s) of the rough opening. Once the screw(s) are readjusted, the jamb or frame/jamb can be placed back into the rough opening. This trial and error cycle of adjustment can be repeated until proper spacing and squaring up is attained. It should therefore be realized that this construction method may be rather tedious and time-consuming. Moreover, the screw(s) are often knocked or tapped out of place by the jamb if precise care is not taken in placement of the window or door jamb, thereby necessitating further time-consuming iterations of adjustments.
[0005] It is, therefore, desirable to provide an apparatus and related method for quickly and easily shimming up window or door jambs during its installation into a rough opening.
SUMMARY OF THE INVENTION
[0006] It is an object of the present invention to obviate or mitigate at least one disadvantage of previous shimming apparatus and methods.
[0007] In a first aspect, the present invention provides a method of installing a construction unit within a pre-framed rough opening, the method including: embedding a plurality of adjustment mechanisms within an inner edge of a rough opening; inserting a construction unit within the rough opening for abutment with the plurality of adjustment mechanisms; and engaging each one of the plurality of adjustment mechanisms with a wrench in a rotating manner so as to adjust the abutment of the construction unit with the one or more adjustment mechanisms; wherein iteratively engaging of each one of the plurality of adjustment mechanisms serves to shim the construction unit within the rough opening until the construction unit is squarely secured within the rough opening.
[0008] In a further embodiment, there is provided an apparatus for installation of a construction unit within a pre-framed rough opening, the apparatus including: a head section including a screw interface for operative engagement with a screwdriver, a first disk-like surface for abutting engagement with the construction unit, a nut-like structure for operative engagement with a wrench; a threaded section affixed to the head section, the threaded section including a threaded surface for retained engagement with a rough opening, a screw head forming the screw interface flush with the first disk-like surface; and wherein adjustment of the apparatus via the wrench in operative engagement with the nut-like structure provides support to the construction unit within the rough opening via the first disk-like structure.
[0009] In further aspect, the present invention provides a kit for installation of a construction unit within a pre-framed rough opening, the kit including: a plurality of adjustment mechanisms each capable of shimming an outer edge of a construction unit against an inner surface of a rough opening, each one of the adjustment mechanisms having a head section including a screw interface for operative engagement with a screwdriver, a first disk-like surface for abutting engagement with the construction unit, a nut-like structure; a threaded section affixed to the head section, the threaded section including a threaded surface for retained engagement with a rough opening, a screw head forming the screw interface flush with the first disk-like surface; and a wrench capable of rotation of each the adjustment mechanism by way of operative engagement with the nut-like structure such that the first disk-like surface provides support to the construction unit within the rough opening.
[0010] Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Embodiments of the present invention will now be described, by way of example only, with reference to the attached Figures, wherein:
[0012] FIG. 1A is an elevation view of a window in place with adjustment mechanisms in accordance with the present invention with one corner of such window circled in enlargement.
[0013] FIG. 1B is the enlargement shown circled in FIG. 1A .
[0014] FIG. 2 is a partially cut-away three-dimensional illustration of the embodiment illustrated in FIG. 1B with adjustment mechanisms in accordance with the present invention and further being tightened via a wrench.
[0015] FIG. 3 is a three-dimensional view of the first embodiment of an adjustment mechanism in accordance with the present invention.
[0016] FIG. 4 is a three-dimensional view of the second embodiment of an adjustment mechanism in accordance with the present invention.
DETAILED DESCRIPTION
[0017] Generally, the present invention provides a method and apparatus that fulfills rapid installation of a construction unit which may be varied construction items, such as jambs of windows and doors, into a rough opening. Moreover, the present invention advantageously enables accurate adjustment of the given construction item being installed including shimming and squaring-up of the construction items relative to the rough opening into which it is being installed. This improves repeatability of quick installations with reduced errors such that quality of construction can be maintained and improved without time-consuming and costly labor. Still further, the present invention also serves to reduce the necessary construction skills required during, for example, window jamb or door jamb installation into a rough opening thereby enabling do-it-yourself homeowners to undertake work typically otherwise done by skilled carpenters.
[0018] With reference to FIG. 1A , there is illustrated an elevation view 100 of a window unit 10 in place with adjustment mechanisms (several being labeled as elements 11 a through 11 d ) in accordance with the present invention with one corner of such window 10 circled in enlargement. FIG. 1B is the enlargement shown circled in FIG. 1A . It is clear, therefore, from FIGS. 1A and 1B that the window unit 10 is shown within the rough opening of a section of a framed wall shown in the enlargement by studs 12 , 13 , and 14 . Such roughed-in framing construction is well known in the carpentry art and will not be further described herein. The window unit 10 typically includes a trim board which forms the jamb 10 a whereby a gap exists between the inner surfaces of the rough opening and the trim board of the window unit. It is within this gap that the inventive adjustment mechanism resides. In this particular arrangement as shown, there are ten adjustment mechanisms (several being labeled as elements 11 a through 11 d ) placed at even intervals around the periphery of the jamb 10 a . It should be understood that while ten such adjustment mechanisms are shown, there may be more or fewer used depending upon the dimensions of the given window unit. For example, a large window unit may require many more such adjustment mechanisms. Likewise, a very wide but short window unit may requirement many adjustment mechanisms on the longer top and bottom gaps, but much fewer on the shorter side gaps. Thus, the given window unit will dictate the precise placement and number of adjustment mechanisms.
[0019] It should further be understood that although a window unit is shown and described in conjunction with the present invention, the inventive adjustment mechanisms may indeed be used in any other implementation including, but not limited to, installation of door units within rough openings. Moreover, the common feature of a framed unit (e.g., window, door, or other similar structures requiring squaring up) being installed within a rough opening is a requirement for applicability of the present invention.
[0020] With regard to FIG. 2 , there is illustrated a partially cut-away three-dimensional illustration which corresponds to the structure of FIG. 1B and whereby an adjustment mechanism in accordance with the present invention being tightened via a wrench 20 . In particular, this illustrates a first embodiment 30 of the inventive adjustment mechanism which is further illustrated in the three dimensional view of FIG. 3 . In this first embodiment 30 , the adjustment mechanism includes a threaded section 32 with self-tapping tip 31 , and a head section 35 . The threaded section 32 is configured to engage the inner surface of the rough opening. Commonly, the rough opening will be provided in terms of wooden studs. In such instance, the threaded section 32 would be configured to include larger threads suitable for engagement with wood. However, if the rough opening was formed via some other material such as steel framing or concrete material (e.g., cinder blocks), then it should be readily apparent that the threaded section 32 would include, respectively, finer metal threads or hardened masonry threads and for example a self-tapping tip 31 with a hardened carbide tip (not shown). Overall, it should be readily apparent that different sized threads may be required for different rough opening materials.
[0021] With further reference to FIG. 3 , the head section 35 is seen to include two disk-like surfaces 33 and 34 with an intermediate portion 36 situated there between. While the two disk-like surfaces 33 and 34 include a circumferential periphery, the intermediate portion 36 includes a sectioned outer periphery having six (6) flat edges which preferably forms a hexagonal nut structure. The intermediate portion 36 is therefore able to be engaged with a standard wrench so long as the hexagonal nut structure formed is dimensioned for the given wrench used. The two disk-like surfaces 33 and 34 basically form a slot there between such that the wrench is slotted therein. In other words, the present invention may include an intermediate portion 36 which corresponds to a standardized wrench size using, for example, ISO Metric, American/English, British Standard, or any other standardized sizes. Thus, it should be understood that the particular dimensions of the intermediate portion 36 may vary without straying from the intended scope of the present invention. Likewise, though a hexagonal nut formation is described herein as preferred, it should be readily apparent that variations in the shape of the nut formed (e.g., square nut) may occur without straying from the intended scope of the present invention.
[0022] The gap between the two disk-like surfaces 33 and 34 in which the intermediate portion resides should be sufficiently dimensioned so as to allow a standard wrench to fit therein. However, while such standardization is desirable, it should also be understood that a proprietary width may be useful such that a non-standard, thin gap between the two disk-like surfaces 33 and 34 would therefore require a correspondingly non-standard, thin wrench. It should be understood that the benefit to a proprietary thin gap with related proprietary thin wrench would be an advantageous ability of the present invention to be used within tight workspaces where very little room is available in the gap between the window jamb's outer edge and the rough opening's inner surface. In such instance, the present invention may be provided in the form of a kit where such kit would be made available with a minimum set of adjustment mechanisms combined with a correspondingly sized, non-standard wrench. It should therefore be readily apparent that such wrench provided within the kit may be non-standard in both its thickness and also with regard to the sizing and engagement with the nut-like intermediate portion. Thus, the intermediate portion 36 may also be a non-standard nut size and/or dimension (e.g., a 7-sided nut having a maximum radius of 3.875 mm or any other proprietary configuration).
[0023] With further reference to FIG. 4 , there is illustrated a three-dimensional view of the second embodiment 40 of an adjustment mechanism in accordance with the present invention. This second embodiment 40 is similar to the first embodiment 30 except that only one disk-like surface 43 is provided in the head section 45 of the adjustment mechanism. Here, the single disk-like surface 43 exists on the head position at the extreme opposite from the tip 41 of the threaded section 42 which itself screws into the inner edge of the rough opening. Engagement with a wrench (either standard sizing or non-standard sizing) is accomplished in a manner similar to that described hereinabove with regard to the first embodiment 30 . However, it should be understood that because only one disk-like surface 43 exists, there is no slot to retain a wrench. Rather, a user would require somewhat more dexterity in manipulating the wrench during use of the second embodiment 40 versus the first embodiment 30 . Notwithstanding this minor difference, one benefit of a single disk-like surface 43 resides in reduced materials required during manufacture of the second embodiment 40 .
[0024] In either embodiment 30 or 40 with either the single or double disk-like surface(s), the same principles of installation apply. Both embodiments involve a threaded section which first engages the inner edge of the rough opening. Preferably, the threaded section is self-tapping such that a minimal amount of pressure exerted by the user may initially embed the adjustment mechanism. The threaded section may be a metal screw (for example only—a zinc 8×1¼″ phillips hex washer full thread self-drilling screw—though other sizes are possible) whereby the head section (of either embodiment) may be formed of a hardened resin shaped into the nut-like structure with either the single or double disk-like surface(s). It should be readily apparent that more durable screws may be used for installations where steel studs will need to be penetrated. In either embodiment, the metal screw Phillips head would present itself flush with the outer disk-like surface. In this manner, a user could utilize a standard Phillips head screwdriver to initially set the adjustment mechanisms at spaced intervals along the inner edge of the rough opening. While a manual screwdriver is possible, it should be understood that a motorized device may be used such as, but not limited to, air impact drivers or battery operated screwdrivers. Once the adjustment mechanisms were set firmly in place, the user would set in the jamb to generally rest upon each outer disk-like surface. Because the metal screw Phillips head would therefore no longer be accessible buy the user, a suitable wrench would then be used to fine tune the adjustment of each adjustment mechanism thereby shimming up the installed jamb within the rough opening until the jamb is squared up and firmly seated. The adjustment mechanisms would therefore remain permanently in place and the window framing completed.
[0025] As mentioned, in either embodiment the head section is formed integrally of a hardened resin material. High impact plastic may be a suitable material for this, though any moldable and suitably durable material may be used for the head section without straying from the intended scope of the present invention. Likewise, in either embodiment the threaded section is formed of a metal screw. The head of the screw should be held exposed but flush within the head section to enable a screwdriver access to initially embed the threads within the inner edge of the rough opening. It should be readily apparent that although a phillips head metal screw is shown and described, any particular screw head and related screwdriver may be utilized such as flat, star, hex, or any other configuration without straying from the intended scope of the present invention.
[0026] In manufacture of the present invention, the size of the disk-like surface(s) of either embodiment may be variable. For example, some implementations may involve use with windows that may be relatively large and/or weighty. In such instances, the disk-like surface(s) would be molded to be relatively larger in diameter so as to provide more surface area abutting, and thereby supporting, the window jamb. Likewise, smaller windows may require smaller disk-like surface(s). Still further, the threaded section may vary in size depending upon the given application. Yet still further, it should be readily apparent that when the embodiment as seen in FIG. 3 is provided having two disk-like surfaces each surface may vary in diameter relative to one another—i.e., the first disk-like surface abutting the jamb may be larger or smaller than second disk-like surface. Accordingly, changes in sizes should not vary the intended scope of the present invention.
[0027] It should also be apparent to those well versed in the materials art that the adjustment mechanism in accordance with the present invention should be manufactured in such a manner so as to avoid decoupling of the head section's material with the threaded section's material. A variety of methods may be useful in appropriately joining the head section with the threaded section. These methods may include providing the metal screw head with scoring or knurling prior to molding of the head section thereon. Likewise, the metal screw may be of non-standard type that is customized with protrusions which assist in anchoring the screw to the molded head section. It has also been found to be useful with regard to manufacture of the present invention to first heat treat the metal screw of the threaded section for embedding within the pre-molded head section. In this manner, the seating of the metal screw is markedly improved thus improving the integrity of the joint between differing materials.
[0028] The above-described embodiments of the present invention are intended to be examples only. Alterations, modifications and variations may be effected to the particular embodiments by those of skill in the art without departing from the scope of the invention, which is defined solely by the claims appended hereto. | A method, apparatus, and kit for adjustment of a construction unit with a rough opening. The construction unit may be a window, door, or similar construction element that requires shimming and squaring up within a rough opening. An adjustment mechanism is included that has a head section and threaded section. The head section engages the construction unit by abutment and the threaded section engages the rough opening by threaded retention. After initial embedding of the adjustment mechanism within the inner surface of the rough opening, the adjustment mechanism is rotationally engaged via a wrench for fine-tuned shimming of the construction unit. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to the structure of a photodiode used in an optical transceiver module for an optical communication system in which one optical fiber is used for carrying out transmission and reception of signals by using two different wavelengths, λ1 and λ2 (λ1<λ2). The photodiode can detect light having a shorter wavelength, λ1, by dexterously eliminating the influence of outgoing light having a longer wavelength, λ2. It should be noted that the photodiode is for detecting light having a shorter wavelength, not for detecting light having a longer wavelength. To be blocked is the light having a longer wavelength, not the light having a shorter wavelength.
[0003] 2. Description of Related Arts
[0004] When one optical fiber is used for both transmission and reception of signals, a laser diode (LD), which emits outgoing light, and a photodiode (PD), which receives incoming light, are placed usually in the same housing or on the same platform. Similarly, when one optical fiber is used for transmitting signals uni-directionally by using two or more different wavelengths, two or more PDs are placed usually on the same platform. A PD is a device having high sensitivity. An LD emits intense outgoing light to transfer signals to a distant place. Although the PD and LD act at different wavelengths, the PD has sensitivity to the outgoing light and detects it. When an LD and a PD are placed on the same terminal, if the PD detects the outgoing light emitted by the LD, this phenomenon is called optical crosstalk. The outgoing light acts as noise for the PD. When the PD detects the outgoing light, incoming light cannot be detected accurately. Therefore, it is necessary to minimize the crosstalk between the PD and LD. Undoubtedly, there can be electrical crosstalk between a transmitter and a receiver caused by the magnetic coupling between their electric circuits. However, to be solved here is the problem of optical crosstalk.
[0005] Researchers and engineers have devised various types of transceivers that carry out transmission and reception of signals over one optical fiber. Those transceivers employ different methods for separating the outgoing light and incoming light. The most popular method uses an optical wavelength demultiplexer to branch the path for the outgoing light and the path for the incoming light. Such a method in which the two paths are separated spatially can solve the problem of optical crosstalk relatively easily. There is a rather special transceiver module in which a PD and an LD are arranged in a straight line. Such a method in which almost the same path is used for both transmission and reception makes it difficult to solve the problem of optical crosstalk.
[0006] [0006]FIG. 1 shows a system of simultaneous bidirectional optical communication in which one optical fiber connects a central office and a subscriber for carrying out bidirectional signal transmission by using two different wavelengths, λ1 and λ2. This is a system of wavelength division multiplexing (WDM) bidirectional communication. A central office generates a signal using LD1 and sends it to PD2 at a subscriber via an optical fiber 1 , an optical wavelength demultiplexer 2 , an optical fiber 3 , an optical wavelength demultiplexer 4 , and an optical fiber 5 . The subscriber generates another signal using LD2 and sends it to PD1 at the central office via an optical fiber 6 , the optical wavelength demultiplexer 4 , the optical fiber 3 , the optical wavelength demultiplexer 2 , and an optical fiber 7 . Thus, signals can be transmitted in opposite directions at the same time over one optical fiber.
[0007] At the central office, the optical wavelength demultiplexer 2 is connected to the optical fibers 7 and 1 to separate an upstream signal and a downstream signal according to their wavelengths. The outgoing light carrying downstream signals has the wavelength λ2 and the incoming light carrying upstream signals has the wavelength λ1. The downstream and upstream signals travel over the one optical fiber 3 at the same time.
[0008] At the subscriber, the optical wavelength demultiplexer 4 is connected to the optical fibers 5 and 6 to separate incoming light and outgoing light. The photodiode PD2 receives incoming light having the wavelength λ2, and LD2 generates outgoing light having the wavelength λ1. Although not shown, there are individual electric circuits beyond PD2 and LD2.
[0009] The present invention addresses problems related to a transceiver at a central office. Problems at a central office are different from those at a subscriber because the aspect related to wavelength is reversed In the example shown in FIG. 1, the optical wavelength demultiplexers 2 and 4 spatially separate the optical paths of the outgoing light and the incoming light. Therefore, the problem of optical crosstalk can be solved by the improvement of the performance of the optical wavelength demultiplexer, for example. The problem to be solved by the present invention is the optical crosstalk between the PD and LD at a central office.
[0010] [0010]FIG. 2 shows another system in which two signals are transmitted unidirectionally from a central office to a subscriber by using different wavelengths, λ1 and λ2. This is a system of WDM unidirectional communication. A central office generates two signals by using two different LDs. They are combined at an optical wavelength multiplexer 8 and transmitted from the central office to a subscriber over one optical fiber. At the subscriber, the two signals are separated according to their wavelengths by an optical wavelength demultiplexer 4 . The photodiodes PD1 and PD2 selectively receive the signals. Here, crosstalk between PD1 and PD2 also poses a problem.
[0011] [0011]FIG. 3 shows a typical example of a conventional PD module used as a receiver in an optical communication system in which the optical paths are separated as shown in FIGS. 1 and 2. This type of PD module is still mainly used. Lead pins 9 are provided at a circular metal stem 10 , at the center of which a submount 11 supports a PD chip 12 . A lens 13 is attached to a cylindrical cap 14 welded to the stem 10 in alignment. A cylindrical sleeve 15 is placed on the cap. A ferrule 16 is inserted into the mandrel hole of the sleeve 15 . The ferrule 16 supports the end of an optical fiber 17 . The tip of the ferrule 16 is polished on the skew. The sleeve 15 is covered with a bend limiter 18 to protect the optical fiber 17 . This explains the structure of a PD module currently in use. The systems shown in FIGS. 1 and 2 also include LD modules. In an LD module, only the PD shown in FIG. 3 is replaced by an LD. Therefore, an LD module has a structure similar to that of a PD module, and no explanation about it is provided here. PD modules and LD modules now in use employ a metal case, so that optical fibers are arranged stereoscopically (three-dimensionally). Although high in performance, those modules require centering work at the time of assembly. The centering is a time-consuming job and increases the manufacturing cost. Because of the high price, those modules are not suitable in achieving widespread application.
[0012] Researchers and engineers have been energetically studying surface-mounted types for use as less costly PD modules, LD modules, or PD-LD modules. FIG. 4 shows an example of a conventional surface-mounted-type module that uses a back-illuminated-type PD. A rectangular silicon platform 19 is provided with a longitudinal, V-shaped groove 20 at the center. The groove is formed by etching. A slanted mirror face 21 is provided at the end of the V-shaped groove 20 . The etching work simultaneously forms the mirror face 21 also. A PD chip 23 is fixed directly above the end portion of the V-shaped groove 20 . The PD chip 23 , a back-illuminated-type PD, is provided with a photo-sensitive area 24 at the upper zone. The light emerging from an optical fiber 22 propagates in the V-shaped groove 20 in parallel with the surface of the silicon platform, is reflected upward by the mirror face 21 , enters the PD 23 at the back side, and reaches the photo-sensitive area 24 . A surface-mounted-type module has no centering portion. Elimination of centering work accomplishes easy manufacturing.
[0013] Both the PD modules shown in FIGS. 3 and 4 can be used for detecting the incoming light separated by the optical wavelength demultiplexers shown in FIGS. 1 and 2. An optical wavelength demultiplexer can be produced, for example, by forming a wavelength-selective branching waveguide on a silicon platform. There is also a prism-type optical wavelength demultiplexer as shown in FIG. 5. A dielectric multilayer film 27 is deposited on the oblique face of transparent triangular-column glass blocks 25 and 26 for wavelength selectivity. For example, when light emerges from an optical fiber 28 , the light having a specific wavelength is reflected and the other light having a different wavelength is transmitted In FIG. 5, however, the wavelength selectivity is used for distinguishing the outgoing light from the incoming light. More specifically, the incoming light (wavelength: λ2) emerging from the optical fiber 28 is reflected by the multilayer film 27 and introduced into a PD 30 . The outgoing light (wavelength: λ1) emitted from an LD 29 passes through the multilayer film 27 and enters the optical fiber 28 .
[0014] However, the present invention whose intention is to minimize the optical crosstalk can be most suitably applied to a transceiver module in which the optical paths are not separated by an optical wavelength demultiplexer. Such a module is called an optical path non-separated type in the present invention in order to distinguish from the foregoing optical path-separated type. In the optical path non-separated type, a PD is placed at the side of the optical fiber and an LD is placed in line with the optical fiber. This type requires no optical wavelength demultiplexer. This is advantageous because the size becomes smaller and the structure becomes simpler. On the other hand, this type has a common optical axis for outgoing light and incoming light. As a result, the problem of optical crosstalk becomes more serious.
[0015] [0015]FIG. 6 shows an example of an optical path non-separated type for a module at a subscriber. The wavelengths of the outgoing light and incoming light are opposite to those at a central office. Although not shown, there is a silicon platform in a housing 31 . An optical fiber 32 is housed longitudinally. An LD 33 is mounted opposite to the end of the optical fiber 32 . A WDM filter 35 is provided at some point in the optical fiber 32 near its end to carry out wavelength distinction. A PD 34 is placed directly above the WDM filter 35 . The outgoing light (wavelength: λ1) emitted by the LD 33 is as powerful as 1 mW, for example. The outgoing light propagates to the outside through the optical fiber 32 . The incoming light (wavelength: λ2) having propagated through the optical fiber 32 from the outside is reflected by the WDM filter 35 , enters the PD 34 at the back side, and is detected by a photo-sensitive area 36 . Whereas the out-going light is intense, the incoming light is weak. The outgoing light propagates to the WDM filter 35 through the same optical fiber 32 in the direction opposite to the incoming light. When passing through the WDM filter, part of the outgoing light may enter the PD. This intruding light causes the optical crosstalk. Notwithstanding the small percentage, the intruding light becomes an un-ignorable noise in comparison with the intensity of the incoming light, because the outgoing light is intense and the incoming light is weak.
[0016] [0016]FIG. 7 shows a conventional PD that has a wide range of sensitivity. When this type of PD is used, the problem of optical crosstalk becomes more serious. The structure of the InP-based PD shown in FIG. 7 is based on an epitaxial wafer in which an n-InP buffer layer 38 , an n-InGaAs absorption layer 39 , and an n-InP cap layer 40 are laminated on an n-InP substrate 37 . At the upper zone of the PD, a p-type region 41 and a p electrode passivation layer 44 are formed. On the bottom surface, a ring-shaped n electrode 45 and an anti-reflection layer 46 are provided. When such a PD is used as a photodetector, the level of the noise caused by the outgoing light becomes higher than the signal level of the incoming light. In other words, the signal/noise ratio (S/N ratio) becomes smaller than one. When an ordinary PD, which has sensitivity to both λ2 and λ1, is used, the foregoing undesirable phenomenon occurs.
[0017] [0017]FIG. 8 is a graph showing the sensitivity characteristics of the PD shown in FIG. 7. The P portion in the shorter wavelength region, in which the sensitivity decreases with decreasing wavelength, corresponds to the bandgap of the InP substrate. The light having a shorter wavelength than that corresponding to the bandgap is not detected because it is absorbed by the InP substrate. The R portion in the longer wavelength region, in which the sensitivity decreases with increasing wavelength, corresponds to the bandgap of the InGaAs absorption layer. The Light having a longer wavelength than that corresponding to the bandgap is not detected because its energy is lower than the bandgap of the absorption layer. In other words, the PD has sensitivity in a wide range of Q from the bandgap wavelength P of the InP substrate to the bandgap wavelength R of the InGaAs absorption layer. Therefore, the PD has sufficient sensitivity not only at the 1.3-μm band but also at the 1.55-μm band.
[0018] As described above, the PD having a conventional structure as shown in FIG. 7 has sensitivity in a wide range of 1.0 to 1.65 μm as shown in FIG. 8. It is advantageous to have sensitivity in a wide range as above because the same PD can be used for both the 1.3-μm band and 1.55-μm band. Therefore, the PD having a structure as shown in FIG. 7 is most widely used for the long-wavelength light employed in optical communications. However, when the PD is used for a transceiver module, the PD also detects the outgoing light in addition to the incoming light, which means that the outgoing light acts as noise. Consequently, the PD is disadvantageous in that optical crosstalk occurs between the outgoing light and incoming light.
[0019] In the transceiver module shown in FIG. 6, not all the intense outgoing light (wavelength: λ1) emitted from the LD placed on the silicon platform (silicon bench) enters the optical fiber. The light emitted from the LD spreads out at a considerably wide angle. Some of the light strikes the silicon platform and plastics to be scattered. The silicon platform is transparent to the outgoing light. The outgoing light having entered the space made by the silicon platform and transparent plastics passes through the silicon, is reflected, and is scattered Various complicated scattered rays of light are produced according to the distribution of the plastics, the shape of the silicon platform, and the arrangement of the other devices. When looked from the PD, the entire silicon platform shines brightly due to the scattering of the outgoing light. Such components of the outgoing light that enter the PD through various paths other than the designed path are called “scattered light” or “stray light.”
[0020] Some components of the outgoing light enter the PD from various directions and at various heights. They enter the PD at the back side, at the front side, and at the side face. Such components of the outgoing light that enter the PD without entering the optical fiber cause the crosstalk. Such crosstalk caused by the scattered light (stray light) that does not pass through the WDM filter cannot be suppressed by the improvement of the performance of the WDM filter. When the output power of the LD is increased, the outgoing light propagating through the optical fiber increases the amount of the leakage at the WDM filter. The component of the outgoing light emitted from the LD that enters the PD after being refracted and reflected at the WDM filter is called “leakage light.”
[0021] The unexamined Japanese patent publication (Tokukaihei) No.4-213876 entitled “Photodetector” proposes a photodetector that is a PD comprising two stages of absorption layers. A layer structure that absorbs 1.55-μm light is provided on an InP substrate and a p electrode is provided on the layer structure. On part of the layer structure, another layer structure that absorbs 1.3-μm light is provided and another p electrode is provided on this layer structure. A common n electrode is provided on the bottom surface of the InP substrate. Consequently, the photodetector has a two-stage structure in which PD1 for absorbing the light having λ1 (1.3 μm) is placed at the top and PD2 for absorbing the light having λ2 (1.55 μm) is placed at the bottom.
[0022] The light having λ2 and the light having λ1 enter the photodetector at the front side. Since the light having λ2 has a longer wavelength, it passes through the upper layer structure and reaches the lower layer structure to generate optical current there. In other words, PD2 absorbs the light having λ2 at the bottom. The light having λ1, which is shorter, is absorbed by PD1 in the upper structure to generate optical current there. In other words, PD1 can detect the light having λ1 at the top. In order to prevent the penetration of the light having λ1 into the lower structure, a layer having a thickness of d=mλ 1/(2n), where m is a plus integer and n is a refractive index, is provided between PD1 and PD2. The object of this layer is to reflect the light having λ1 upward so that the light having λ1 cannot enter PD2. Hence, this layer is called a “selective reflection layer.” If the light having λ1 enters PD2, the light causes PD2 to generate optical current, so that crosstalk occurs. The selective reflection layer is provided to prevent this type of crosstalk.
[0023] However, this patent application provides no preventive measure against crosstalk in the opposite case. Such a case is out of its expectations. There is no measure against the phenomenon that the light having λ2 is reflected by the n electrode at the bottom, returns to PD1, and adversely affects its performance. Since the selective reflection layer provided between PD1 and PD2 reflects the light having λ1 but transmits the light having λ2, the light having λ2 reflected at the bottom face can pass through the layer upward.
[0024] Another unexamined Japanese patent publication, (Tokukaihei) No.9-166717, entitled “Optical receiver module and optical transceiver module” proposes a photodetector for a system in which two signals having different wavelengths, λ1=1.3 μm and λ2=1.55 μm, are transmitted through one optical fiber. A first photodiode, PD1, absorbs the light having λ1 and transmits the light having λ2. A second photodiode, PD2, placed behind PD1, absorbs the light having λ2. Two independent PDs are combined in tandem. They are not such composite devices as described above. The photodiode PD1 has an absorption layer that has an intermediate bandgap wavelength as expressed in λ1<λg<λ2, where λg represents the bandgap wavelength of the absorption layer. Since λg is longer than λ1, the absorption layer absorbs and detects the light having λ1. The light having λ2 passes through PD1 and is detected by PD2. FIG. 9 shows the structure of the PD for absorbing the light having λ1 proposed by Tokukaihei No.9-166717. The PD is placed in an intermediate place to transmit the light having the longer wavelength. For this purpose, the PD has another opening at the side opposite to the light-entering face to allow the light having the longer wavelength to leave the PD. The PD can be called a dual opening type, because it has openings at both sides for transmitting light.
[0025] An n-InP buffer layer 51 , an n-InGaAsP absorption layer 52 (λg=1.42 μm), and an n-InGaAsP window layer 53 are grown epitaxially on an n-IP substrate 50 . At the center portion, Zn is diffused to provide a p-type region 54 . The center portion of the p-type region 54 is covered by an anti-reflection layer 56 . Around the anti-reflection layer 56 , a ring-shaped p electrode 55 is provided At the outside of the p electrode 55 , a passivation layer 57 is formed to protect the edge portion of the pn junction. A ring-shaped n electrode 58 is formed on the bottom surface of the InP substrate 50 . The inside of the n electrode 58 forms an opening and is covered by an anti-reflection layer 59 . Both the front and back sides have openings for transmitting light. The ring-shaped electrodes are provided without overlapping with these openings. The anti-reflection layers are provided at the openings to prevent incident light from attenuating due to reflection.
[0026] [0026]FIG. 10 shows a transmittance spectrum of the InGaAsP absorption layer 52 (λg=1.42 μm). The mixing ratio of its quaternary mixed crystal is decided for the bandgap wavelength to take an intermediate value between 1.3 μm and 1.55 μm. The measured restart proves the design concept. The light having a wavelength shorter than 1.4 μm is absorbed almost completely, which means that the light practically does not pass through the layer. A wavelength of 1.42 μm forms the boundary condition. Almost one hundred percent of the light having a wavelength longer than 1.5 μm passes through the absorption layer. The transmittance varies with the thickness. The absorption layer has an enough thickness so that the light having a shorter wavelength can be absorbed completely.
[0027] The present invention intends to prevent a PD that detects the light having a shorter wavelength from suffering the crosstalk caused by the light having a longer wavelength. In the explanation below, the shorter wavelength, λ1, is supposed to be 1.3 μm and the longer wavelength, λ2, to be 1.55 μm in order to specifically show the relation between the two wavelengths. In the present invention, however, λ1 is in the range of 1.2 to 1.38 μm, and λ2 is in the range of 1.45 to 1.65 μm. At a central office, if a PD as shown in FIG. 7, which usually has sensitivity in a wide range, is used as a photodetector, it also detects the scattered light and leakage light of the outgoing light. At a central office, the incoming light has a wavelength of 1.3 μm, and the outgoing light, 1.55 μm. This combination of wavelengths is advantageous in eliminating the effect of the outgoing light. Dexterous exploitation of the basic properties of the semiconductor enables the production of a PD for a central office that detects the incoming light (λ1=1.3 μm ) but does not detect the outgoing light (λ2=1.55 μm). This can be accomplished by selecting the bandgap wavelength λg of the absorption layer of the PD to satisfy the following formula:
λ1(incoming light)<λg<λ2(outgoing light).
[0028] This is possible because the two wavelengths at a central office have such an advantageous relationship. If the bandgap wavelength λg of the absorption layer is decided to be 1.35 to 1.45 μm, for example, then the absorption layer should have a desirable quality that it detects the incoming light but does not detect the outgoing light. A bandgap wavelength can be adjusted to 1.35 to 1.45 μm by using a quaternary mixed crystal of InGaAsP. In the present invention, however, λg is in the range of 1.3 to 1.5 μm.
[0029] [0029]FIG. 10 shows a light transmittance of an InGaAsP quaternary mixed-crystal layer having a bandgap wavelength of 1.42 μm. The absorption layer of the PD shown in FIG. 9 is made of such a mixed-crystal. Its transmittance is zero for 1.3-μm light (incoming light). In other words, it absorbs and detects 1.3-μm light completely. On the other hand, its transmittance is almost one hundred percent for 1.55-μm light (outgoing light). In other words, it transmits 1.55-μm light almost completely, which means it does not detect 1.55-μm light. Therefore, a PD as shown in FIG. 9, which has wavelength selectivity, can be used singly as a photodetector at a central office. The PD shown in FIG. 9 has an opening both at the front and back sides, because behind the PD another PD for detecting 1.55-μm light is to be placed. However, when a PD is used at a central office, only one opening is required because the PD has only to absorb 1.3-μm light. If the PD is a back-illuminated type, the front side is covered by the p electrode. If the PD is a front-illuminated type, the back side is covered entirely by the n electrode. Such a PD can be used as a photodetector at a central office without modification.
[0030] [0030]FIG. 11 shows a back-illuminated type PD conceived on the basis of the above-described consideration for the use in a central office. Although the PD is almost the same as that shown in FIG. 9, it has a slightly different structure in the vicinity of the p electrode. An n-InP buffer layer 61 , an n-InGaAsP absorption layer 62 (λg=1.42 μm), and an n-InP cap layer 63 are grown epitaxially on an n-InP substrate 60 . At the center portion of the chip, Zn is diffused to provide a p-type region 64 . A p electrode 65 having no opening is provided to cover almost the entire p-type region 64 . Since the front side is not required to admit light, no opening is provided there. At the outside of the p electrode 65 , a passivation layer 67 is formed to protect the edge of the pn junction. Since light enters the PD at the back side, the back-side structure is the same as in FIG. 9. A ring-shaped n electrode 68 is formed on the bottom surface of the InP substrate 60 . The inside of the n electrode 68 forms an opening for admitting light and is covered by an anti-reflection layer 69 . The ring-shaped electrode is provided without overlapping with the opening.
[0031] It should be possible to use a PD having such a structure as a photodetector at a central office. Nevertheless, the present inventors found that when such a PD is used as a photodetector at a central office, crosstalk occurs due to the influence of 1.55-μm light (outgoing light at the central office). It was out of the present inventors' expectations. The InGaAsP absorption layer 62 has a bandgap wavelength of 1.42 μm. Since it is shorter than 1.55 μm, the present inventors expected the absorption layer to be insensitive to 1.55-μm light as an ideal case. However, the result showed differently. The present inventors found that when the absorption layer 62 has a thickness of 5 μm, it detects about 0.2% of 1.55-μm light. The absorption layer absorbs 100% of 1.3-μm light. The fact that the absorption layer detects 1.55-μm light even in small magnitudes poses a problem. Although 1.55-μm light has an energy lower than the bandgap energy, there are some impurity levels in the bandgap, and these levels effect the slight sensitivity to 1.55-μm light. At a central office, there is imbalance in intensity of light. Whereas the 1.55-μm outgoing light generated in the office is intense, the 1.3-μm incoming light having propagated over an optical fiber is weak. The 1.55-μm outgoing light is more intense than the 1.3-μm incoming light by orders of magnitude. Therefore, even the 0.2% sensitivity can produce an un-ignorable magnitude in noise level because the multiplier has a considerable magnitude.
SUMMARY OF THE INVENTION
[0032] An object of the present invention is to offer a photodiode in which crosstalk caused by the intrusion of intense 1.55-μm outgoing light into the 1.3-μm-light detection portion at a central office can be reduced. This reduction in crosstalk can be accomplished by devising the configuration of the photodiode.
[0033] The present invention intends to reduce the crosstalk caused by 1.55-μm light by preventing or impeding the return of the outgoing light (λ2=1.55 μm) to the absorption layer after passing through the absorption layer once. In order to achieve this purpose, a layer for absorbing 1.55-μm light is additionally provided at the inside or at the outside of a PD. In the present invention, this additionally provided absorption layer is called a “filter layer.” Since these filter layers absorb unwanted 1.55-μm light, the light does not return to the absorption layer for 1.3-μm light, or its intensity is notably reduced even if it returns. This measure can effectively reduce the crosstalk to the 1.3-μm light by the 1.55-μm light predominant at a central office. The methods for providing filter layer for absorbing the 1.55-μm light include the following four types:
[0034] Type 1: To replace the InP cap layer by a thick InGaAs cap layer;
[0035] Type 2: To provide an InGaAs filter layer by epitaxial growth and remove its peripheral region;
[0036] Type 3: To laminate an InGaAs filter layer on the p-type region by the selective growing method; and
[0037] Type 4: To laminate a filter layer made of a plastic resin or another material on the entire top surface of a chip.
[0038] When a material that absorbs 1.55-μm light is provided on the p-type region as mentioned above, the 1.55-μm light (outgoing light) that has once passed through the p-type region does not return to the absorption layer, or it loses its intensity notably even if it returns. The methods are not limited to the above-mentioned four types providing that a newly conceived method can achieve a similar effect.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] In the drawings:
[0040] [0040]FIG. 1 is a schematic diagram showing a system of simultaneous bidirectional optical communication in which one optical fiber connects a central office and a subscriber for carrying out bidirectional signal transmission by using two different wavelength, λ1 and λ2;
[0041] [0041]FIG. 2 is a schematic diagram showing a system of simultaneous unidirectional optical communication in which one optical fiber connects a central office and a subscriber for carrying out unidirectional signal transmission by using two different wavelength, λ1 and λ2;
[0042] [0042]FIG. 3 is a partial cutaway and partial cross-sectional view of a conventional PD that is housed in a metal housing and that has a three-dimensional structure;
[0043] [0043]FIG. 4 is a cross-sectional view of a conventional surface-mounted-type PD module;
[0044] [0044]FIG. 5 is a schematic diagram showing the constitution of a prism-type optical wavelength demultiplexer comprising glass blocks provided with a dielectric multilayer film;
[0045] [0045]FIG. 6 is a schematic diagram showing the constitution of a conventional optical transceiver module at a subscriber that has an LD for generating outgoing going light (wavelength: λ1) and a PD for receiving incoming light (wavelength: λ2) (λ1<λ2);
[0046] [0046]FIG. 7 is a cross-sectional view of a conventional PD having an InGaAs absorption layer having sensitivity in a wide range including λ1 and λ2;
[0047] [0047]FIG. 8 is a graph showing the sensitivity-wavelength characteristic of a conventional PD, in which the axis of abscissa represents wavelength (μm) and the axis of ordinate represents sensitivity (A/W);
[0048] [0048]FIG. 9 is a cross-sectional view of the 1.3-μm-light-detecting PD in the combination of a 1.3-μm-light-detecting PD and a 1.55-μm-light-detecting PD that is disclosed in the published Japanese patent application Tokukaihei 9-166717;
[0049] [0049]FIG. 10 is a graph showing the light transmittance-wavelength characteristic of the InGaAsP layer of the PD shown in FIG. 9, in which the axis of abscissa represents wavelength (μm) and the axis of ordinate represents transmittance (%);
[0050] [0050]FIG. 11 is a cross-sectional view of a 1.3-μm-light-detecting PD produced by dosing the front-side opening of the 1.3-μm-light-detecting PD shown in FIG. 9 by the p electrode;
[0051] [0051]FIG. 12 is a cross-sectional view of a PD for detecting light having λ1 (λ1 <λ2) of Type 1 of the present invention, in which an InGaAs cap layer that can absorb light having λ2 is provided on the entire absorption layer;
[0052] [0052]FIG. 13 is a cross-sectional view of a PD for detecting light having λ1 (λ1 <λ2) of Type 2 of the present invention, in which an InGaAs filter layer that can absorb light having λ2 is provided only on the center portion of the cap layer;
[0053] [0053]FIG. 14 is a cross-sectional view of a PD for detecting light having λ1 (λ1 <λ2) of Type 3 of the present invention, in which an InGaAs filter layer that can absorb light having λ2 is selectively grown at the inside of the p electrode.
[0054] [0054]FIG. 15 is a cross-sectional view of a PD for detecting light having λ1 (λ1 <λ2) of Type 4 of the present invention, in which a plastic resin that can absorb light having λ2 is applied to the entire top surface of the chip.
[0055] [0055]FIG. 16 is a cross-sectional view of an example in which the Type 4 PD of the present invention is used for a surface-mounted-type PD module at a central office.
[0056] [0056]FIG. 17 is a cross-sectional view of an example in which the Type 4 PD of the present invention is used for a surface-mounted-type transceiver module at a central office.
DETAILED DESCRIPTION OF THE INVENTION
[0057] The present invention features a back-illuminated-type PD that has on the p-type region a layer made of a material that absorbs light having λ2 for preventing the return of the light after reflection so that the light cannot pass through the absorption layer twice. Although this PD does not prevent the first passage of light having λ2 through the absorption layer, it can prevent the second passage. This concept is realized through the process described below.
[0058] The PD for 1.3-μm light shown in FIG. 9 detects 0.1% of 1.55-μm light. However, the PD for 1.3-μm light produced for central-office use shown in FIG. 11 has a higher sensitivity to 1.55-μm light; it detects 0.2% of 1.55-μm light. Although the two PDs have the same absorption-layer thickness, 5 μm, the effects differ by a factor of two. The study on the difference revealed that the sensitivity increase is caused by the phenomenon that the 1.55-μm light is reflected by the p electrode 65 , which covers the entire p-type region, and passes through the absorption layer once more. In FIG. 11, the thicker arrow represents the light (λ1=1.3 μm) to be detected. This light is absorbed by the InGaAsP absorption layer 62 , generates an optical current in proportion to its intensity, and disappears. This function is in accordance with the design concept and poses no problem. At a central office, however, when the intense outgoing going 1.55-μm light enters at the back side, it passes through the InGaAsP absorption layer 62 upward from under, generating a slight optical current. This does not terminate the action of the light. It is reflected by the under side of the p electrode 65 and passes through the absorption layer 62 once more in the opposite direction, generating optical current again. As a result, crosstalk occurs twice. This is the reason why the PD shown in FIG. 9 has a sensitivity of 0.1% to 1.55-μm light and the PD shown in FIG. 11 has a sensitivity two times as much, 0.2%.
[0059] The present invention intends to reduce the crosstalk caused by 1.55-μm light by preventing or impeding the return of the 1.55-μm light to the absorption layer after passing through the absorption layer once. In order to achieve this purpose, a layer (filter layer) for absorbing 1.55-μm light is additionally provided at the inside or outside of the PD structure. Since these filter layers absorb unwanted 1.55-μm light, the light does not return to the absorption layer for 1.3-μm light, or its strength is notably reduced even if it returns. This measure can effectively reduce the crosstalk to the 1.3-μm light by the 1.55-μm light predominant at a central office. The present invention provides a material that absorbs light having λ2 on the p-type region. The providing methods are classified into four groups, which are explained below, according to their differences.
[0060] Type 1: Thick Cap Layer (FIG. 12)
[0061] [0061]FIG. 12 shows an embodiment of the present invention in which a thick InGaAs cap layer (filter layer) is provided on the absorption layer. An n-InP buffer layer 61 , an n-InGaAsP absorption layer 62 (λg=1.42 μm), and an n-InGaAs cap layer (filter layer) 78 are grown epitaxially on an n-InP substrate 60 . At the center portion of the chip, Zn is diffused to provide a p-type region 64 . Another p-type region is formed at the periphery of the chip at the same time. This additional p-type region is referred to as a Zn-diffused shield layer 71 . A ring-shaped p electrode 65 is provided on the p-type region 64 . Directly under the ring-shaped p electrode 65 , there lies a portion in which the n-InGaAs cap layer 78 is converted into the p-type region. Since the p electrode has an opening at its inside, it is called a ring-shaped electrode. The p electrode 65 can have any inside and outside shapes, such as a circle, oval, square, pentagon, or hexagon (this is to be applied also to Types 2 to 4).
[0062] An InP layer is used usually as the cap layer on the absorption layer. However, InP cannot absorb light having λ2 because it has a wide bandgap. Consequently, Type 1 employs InGaAs in place of InP as the cap layer so that the layer itself can absorb light having λ2. Because InGaAs has a narrow bandgap, it can absorb light having λ2. Therefore, the cap layer can also be called a filter layer.
[0063] An anti-reflection layer 72 is formed on the p-type region 64 at the inside of the p electrode 65 . Since the PD is a back-illuminated type, the anti-reflection layer 72 is not for admitting light, but for allowing the unwanted light having λ2 to leave the PD without being reflected. At the outside of the p electrode 65 , a passivation layer 67 is formed to protect the edge of a pn junction 66 . Since light enters the PD at the back side, the back-side structure is the same as in FIG. 9. A ring-shaped n electrode 68 is formed on the bottom surface of the InP substrate 60 . The inside of the n electrode 68 forms an opening and is covered by an anti-reflection layer 69 . As with the p electrode 65 , the n electrode 68 can have any inside and outside shapes, such as a circle, oval, square, or octagon (this is to be applied also to Types 2 to 4). Table I shows the thickness and carrier concentration of the epitaxial layers.
TABLE I Carrier Layer's thickness concentration Layer's name (μm) (cm −3 ) InGaAs cap layer (filter layer) (78) 5 p = 10 18 InGaAsP absorption layer (62) 5 n = 10 15 InP buffer layer (61) 4 n = 10 15 InP substrate (60) 200 n = 10 18
[0064] The p-InGaAs cap layer is produced by converting the n-InGaAs cap layer 78 into a p type by the diffusion of Zn. The layer is as thick as 5 μm in order to absorb and attenuate light having λ2. The unwanted light having λ2 passes through the absorption layer upward from under. It is absorbed by the cap layer 78 , and the remaining light leaves the PD. Dissimilar to the PD in FIG. 11, the light having λ2 is not reflected by the p electrode, so that it does not return to the absorption layer. The anti-reflection layer 72 provided at the top surface is for preventing the reflection of the light having λ2=1.55 μm when it leaves the PD, not for preventing the reflection of light incident from outside. When stray light having λ2 enters the PD from above, the InGaAs cap layer can prevent the influence of the light. Because the layer has high hole concentration, the hole-electron pairs produced by the absorption of the light having λ2 recombine without generating optical current. In short, Type 1 replaces the InP window layer in the internal structure of a conventional PD by a thick InGaAs cap layer for the purpose of absorbing light having λ2 so that it cannot return to the absorption layer.
[0065] Type 2: Local and Thick Filter Layer (FIG. 13)
[0066] [0066]FIG. 13 shows another embodiment of the present invention in which a thick InGaAs filter layer is provided only at the center portion of a chip. Whereas Type 1 shown in FIG. 12 has a uniformly thick InGaAsP cap layer, Type 2 is designed with the concept that the light having λ2 passing through the center portion of the chip can be handled with a thick filter layer provided only at the center portion. Consequently, the cap layer is made of InP.
[0067] An n-InP buffer layer 61 , an n-InGaAsP absorption layer 62 (λg=1.42 μm), an n-InP cap layer 63 , and an InGaAs filter layer 74 are grown epitaxially on an n-InP substrate 60 . At the center portion of the chip, Zn is diffused to provide a p-type region 64 . Another p-type region is formed at the periphery of the chip at the same time. This additional p-type region is a Zn-diffused shield layer. The peripheral portion of the InGaAs filter layer 74 is removed so that the center portion, which is converted into a p-type region, can be remained. A ring-shaped p electrode 70 is provided on the protruding portion at the center. An anti-reflection layer 72 is formed on the InGaAs filter layer 74 at the inside of the p electrode 70 . Since the PD is a back-illuminated type, the anti-reflection layer 72 is not for admitting light, but for allowing the unwanted light having λ2 to leave the PD without being reflected.
[0068] Directly under the ring-shaped p electrode 70 , there lies the p-InGaAs filter layer 74 , followed by the p-InP cap layer and the p-InGaAsP absorption layer Usually, an InP cap layer is placed on the absorption layer. However, InP has a wide bandgap and cannot absorb light having λ2. Consequently, Type 2 further laminates an InGaAs layer, which can absorb light having λ2, on the InP cap layer. Dissimilar to Type 1, this type absorbs light having λ2 by the thick InGaAs filter layer provided only at the center portion.
[0069] At the outside of the InGaAs filter layer 74 , a passivation layer 67 is provided to protect the edge of the pn junction. Since light enters the PD at the back side, the back-side structure is the same as in FIG. 12. A ring-shaped n electrode 68 is formed on the bottom surface of the n-InP substrate 60 . The inside of the n electrode 68 forms an opening and is covered by an anti-reflection layer 69 . The p-InGaAs filter layer 74 has a thickness of 5 μm and a carrier concentration of p =10 18 cm −3 . The layer is as thick as 5 μm in order to absorb and attenuate light having λ2. The unwanted light having λ2 passes through the absorption layer upward from under. It is absorbed by the filter layer, and the remaining light leaves the PD. Dissimilar to the PD in FIG. 11, the light having λ2 is not reflected by the p electrode, so that it does not return to the absorption layer.
[0070] The anti-reflection layer 72 provided at the top surface is for preventing the reflection of the light having λ2=1.55 μm when it leaves the PD, not for preventing the reflection of light incident from outside. When stray light having λ2 enters the PD from above, the InGaAs filter layer 74 can prevent the influence of the light. Because the layer has high hole concentration, the hole-electron pairs produced by the absorption of the light having λ2 recombine without generating optical current. In short, Type 2 additionally provides a thick InGaAs filter layer for absorbing light having λ2 so that it cannot return to the absorption layer.
[0071] Type 3: Selectively Grown Thick Filter Layer (FIG. 14)
[0072] [0072]FIG. 14 shows yet another embodiment of the present invention in which a thick filter layer is provided at the center portion of a chip. In Type 2 shown in FIG. 13, the layers up to and including the filter layer are formed by the epitaxial growth method. Type 3, however, uses an ordinary epitaxial wafer in which the layers up to and including an n-InP cap layer are grown. An InGaAs filter layer at the center portion is selectively grown by utilizing the electrode structure after the formation of the pn junction.
[0073] An n-InP buffer layer 61 , an n-InGaAsP absorption layer 62 (λg=1.42 μm), and an n-InP cap layer 63 are grown epitaxially on an n-InP substrate 60 . At the center portion of the chip, Zn is diffused to provide a p-type region 64 . Another p-type region is formed at the periphery of the chip at the same time. This additional p-type region is a Zn-diffused shield layer. A ring-shaped p electrode 70 is provided on the p-type region 64 . At the outside of the ring-shaped p electrode 70 , a passivation layer 67 is provided to protect the pn junction.
[0074] An InGaAs filter layer 75 that absorbs light having λ2 is selectively grown on the center portion of the chip's top surface that is surrounded by the ring-shaped p electrode 70 . The filter layer can be epitaxially grown by a method such as molecular-beam epitaxy (MBE), metalorganic chemical vapor deposition (MOCVD), etc. Because InGaAs cannot grow on the passivation layer and the metal electrode, it selectively grows only on the InP cap layer. Since the p electrode lies outside the periphery of the InGaAs filter layer 75 , no electric field exists in the InGaAs.
[0075] A ring-shaped n electrode 68 and an anti-reflection layer 69 are formed on the bottom surface. Incoming light (λ1=1.3 μm) and outgoing light (λ2=1.55 μm) enter at the back side. The light having λ1 is absorbed by the absorption layer 62 and detected by generating optical current. The light having λ2 passes through the absorption layer upward after being absorbed slightly by the absorption layer. The light having λ2 is absorbed mainly by the InGaAs filter layer 75 . Even if a slight amount of the light having λ2 leaves the PD, the amount of the light reflected somewhere at the outside further decreases. Virtually no light having λ2 returns to the absorption layer 62 . The light having λ2 passes through the absorption layer only once. Therefore, the crosstalk caused by the returning light having λ2 can be prevented effectively.
[0076] Type 4: Chip Whose Entire Top Surface is Covered by Plastic (FIG. 15)
[0077] Types 1 to 3 absorb light having λ2 by the semiconductor material InGaAs. However, the light can be absorbed also by plastic. FIG. 15 shows such an embodiment. An n-InP buffer layer 61 , an n-InGaAsP absorption layer 62 (λg=1.42 μm), and an n-InP cap layer 63 are grown epitaxially on an n-InP substrate 60 . Table II shows the thickness and carrier concentration of the epitaxial layers.
TABLE II Carrier Layer's thickness concentration Layer's name (μm) (cm −3 ) InP cap layer (63) 3 n = 5 × 10 15 InGaAsP absorption layer (62) 5 n = 10 15 InP buffer layer (61) 4 n = 10 15 InP substrate (60) 200 n = 10 18
[0078] At the center portion of the chip, Zn is diffused to provide a p-type region 64 . Another p-type region is formed at the periphery of the chip at the same time. This additional p-type region is a Zn-diffused shield layer A ring-shaped p-electrode 70 is provided on the p-type region 64 . At the outside of the ring-shaped p electrode 70 , a passivation layer 67 is provided to protect the pn junction. No anti-reflection layer is provided at the inside of the p electrode 70 . A ring-shaped n electrode 68 and an anti-reflection layer 69 are formed on the bottom surface. They are produced through the wafer process. After a chip is cut out from the wafer and mounted on a package, the p electrode 70 is connected to a lead pin with a lead wire 77 . Then, a plastic resin 76 that absorbs light having λ2 is applied to the entire top surface of the chip. The plastic resin is required to absorb light having λ2; it is not required to absorb the light exclusively. Therefore, the plastic resin can be black.
[0079] Incoming light (λ1=1.3 μm) and outgoing light (λ2=1.55 μm) enter at the back side. The light having λ1 is absorbed by the absorption layer and detected by generating optical current. The light having λ2 passes through the absorption layer upward after being absorbed slightly by the absorption layer. Then, the light leaves the cap layer and is absorbed by the plastic resin 76 . Only a slight amount of the light having λ2 leaves the PD. Even if the light is reflected at the case and parts, it does not return to the absorption layer. As with Types 1 to 3, the light having λ2 passes through the absorption layer only once. Therefore, the crosstalk caused by the returning light having λ2 can be prevented effectively. Type 4 requires no extra epitaxial growth. Type 4 accomplishes its purpose by applying the plastic resin after the chip is mounted on a package. As a result, Type 4 can be employed easily in practical application.
EXAMPLES
[0080] [0080]FIG. 16 shows a surface-mounted-type PD module on which a Type 4 PD is mounted. A V-shaped groove 81 is provided longitudinally on the surface of an Si platform 80 . A mirror face is provided at the end of the V-shaped groove. An optical fiber 82 is inserted into the V-shaped groove 81 and fixed there. A back-illuminated-type PD 83 of the present invention is fixed on the V-shaped groove 81 . Although it is a back-illuminated type, the PD has an opening at the top surface through which light can pass. The top surface is covered by a plastic resin 85 that absorbs light having λ2.
[0081] At a central office, the incoming light having λ1 emerges from the optical fiber 82 , enters the V-shaped groove 81 , is reflected at the mirror face, and enters the PD 83 at the back side. The light reaches an absorption layer 84 , generates optical current, and is detected by the PD. When the stray light and scattered light produced by the intense outgoing light having λ2 enter the PD from the V-shaped groove, the absorption layer scarcely detects them. After passing through the absorption layer upward, they do not return to the absorption layer. There also exists stray light having λ2 above the PD. However, since it is absorbed by a plastic resin 85 , it does not enter the absorption layer of the PD. Consequently, light having λ2 passes through the absorption layer only once. Therefore, crosstalk caused by the light having λ2 can be suppressed to 0.1% or less. The plastic resin can be applied to the PD at the stage of the chip mounting, without increasing the wafer process.
[0082] [0082]FIG. 17 shows a schematic- cross-sectional view of a surface-mounted-type optical transceiver module that uses a Type 4 PD. The transceiver module is constructed on an Si platform, which is not shown in FIG. 17, in a housing 86 . An optical fiber 87 is attached to the Si platform. An LD 89 for generating outgoing going light having λ2 at a central office is mounted opposite to the end of the optical fiber. A WDM filter 88 is provided on the skew at some point in the optical fiber near its end Aback-illuminated-type PD 90 of the present invention is placed obliquely above the WDM filter. The PD 90 is a Type 4 PD, which has on the top surface a plastic resin 92 that can absorb light having λ2.
[0083] A signal carried by the outgoing light (λ2=1.55 μm) emitted from the LD 89 enters the optical fiber 87 to be transmitted to a subscriber The incoming light (λ1=1.3 μm) carrying a signal from the subscriber propagates through the optical fiber 87 , is reflected by the WDM filter 88 , enters the PD 90 at the back side, and is absorbed by an absorption layer 91 , generating optical current. The intense outgoing light having λ2 generated by the LD 89 produces stray light and scattered light, which surround the PD. The light having λ2 which enters the PD at the back side passes through the absorption layer once, generating optical current sightly. However, the light having λ2 which enters the plastic resin 92 at the top surface is absorbed by the plastic resin, without penetrating into the PD. Therefore, the module can minimize the influence of the outgoing light at a central office.
[0084] Industrial Applicability
[0085] A central office receives light having a shorter wavelength (λ1=1.3 μm) and transmits light having a longer wavelength (λ2=1.55 μm). When the bandgap wavelength of a semiconductor is represented by λg, the light having λ2, which is longer than λg, was thought to pass through the semiconductor without causing any influence. Therefore, the phenomenon that the light having λ2 causes crosstalk to the light having λ1 was not known to a person skilled in the art. There was no concept that light having a longer wavelength causes crosstalk, to a PD for a shorter wavelength. In other words, the present inventors first found the necessity of reducing the above-mentioned crosstalk.
[0086] The present inventors first found that contrary to the conventional knowledge, the absorption layer of a PD for a shorter wavelength, λ1, slightly detects a longer wavelength, λ2. The present invention admits that in a back-illuminated-type PD for λ1, light having λ2 passes through the absorption layer once. The present invention, however, prevents the light from passing through the layer again after being reflected The first passage generates a crosstalk of 0.1%; the second passage increases it to 0.2%. The present invention prevents this increase and thereby enables the reduction of the crosstalk hitherto unknown to a person skilled in the art. | A photodiode that is used in an optical communication system using two different wavelengths, λ1 and λ2 (λ1<λ2), and that enables a reduction in the optical crosstalk caused by outgoing light having a longer wavelengths, λ2. A photodiode that receives light having a shorter wavelengths, λ1, is provided with an absorption layer made of a mate having a bandgap wavelength, λg. (λ1<λg<λ2), to detect the light having λ1. A filter layer that absorbs unwanted light having λ2 is provided over the absorption layer so that the light having λ2 cannot return to the absorption layer after passing through it once. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation in part of co-pending U.S. patent application Ser. No. 09/442,286 entitled Cylinder Cleaning Device filed in the name of Avi Ben-Porat et al. on Nov. 19, 1999, the entirety of which is incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The present invention relates to a take-up shaft used for the cleaning of a cylinder of a printing press and more particularly, to a novel device and method of attaching a cleaning cloth to the take-up shaft for small printing presses.
BACKGROUND OF THE INVENTION
[0003] One of the more difficult and time consuming tasks in the operation to clean a cylinder used in a printing press is the need to periodically remove and replace the cleaning fabric used in clearing the cylinder.
[0004] In a cylinder cleaner in which a supply of cleaning fabric is supplied to a cleaning fabric take-up roll, the cleaning fabric historically is drawn off a supply roll and secured to the take-up shaft by means of a plurality of nails or screws. The supply shaft containing the cleaning fabric is then installed onto two support members bolted to the main frame of the printing press.
[0005] In order to install or remove the supply roll and take-up roll from the support members, an operator first inserts the supply roll onto the support members and then attaches the cleaning fabric to the take-up roll by physically hammering or screwing the cleaning fabric to the take-up roll. This is accomplished by drawing out some of the cleaning fabric from the supply roll, attaching the cleaning fabric to the take-up roll and then rolling up the excess cleaning fabric onto the take-up roll, and then connecting the take-up roll to the support members. Alternatively, the cleaning fabric is attached to the take-up shaft before the supply roll is attached to the support members.
[0006] In order to remove the cleaning fabric from the take-up shaft, the cleaning fabric must be physically taken off the take-up shaft which can ruin the take-up shaft or rip the cleaning fabric. Since space is limited, especially in small printing presses, the ability to hammer or screw the cleaning fabric to the take-up shaft is problematic. Therefore, a need exists for a cleaning fabric take-up shaft that easily secures the cleaning fabric to the take-up shaft without the need to physically hammer or screw the fabric to the take-up shaft.
[0007] Additionally, the used cleaning fabric is typically removed from the cleaning device by unwinding the used fabric from the take-up shaft, which is permanently secured to the support frame. Therefore, a need exists for an efficient system for securing the supply roll and take-up shaft onto the printing press frame.
SUMMARY OF THE INVENTION
[0008] The shaft solves these and other needs associated with a cleaning cylinder device. The shaft was developed to maximize production time by reducing press down time during which the operators of a printing press insert and remove cleaning fabric supply roll and used cleaning fabric of a cylinder cleaner.
[0009] Features of the shaft for a cylinder cleaning device include a rigid one piece frame. Generally described, the rigid one piece frame supports a cleaning fabric supply roll, a cleaning fabric take-up shaft, and an inflatable bladder assembly. The shaft includes a rod that may be mounted or disposed by a locking connection and an axial groove for securing the cleaning fabric from the supply roll to the take-up roll. Both the supply roll and the take-up shaft are removably attached to the one piece frame.
[0010] In addition, shaft includes a rod that may be mounted or disposed by a sliding connection, inserted into a cylindrical sockets for securing the cleaning fabric from the supply roll to the take-up roll.
[0011] The take-up shaft further includes a first member and a second member. The first member has a planar section and a first end and a second end. The first end is larger than the second end. The second member has a proximal end and a distal end. The distal end is larger than the proximal end. In addition, the overall length of the second member is smaller than that of the first member. The second member is disposed over the first member in such a way that the proximal end of the second member is adjacent to the second end of the first member and the distal end of the second member is adjacent to the first end of the first member.
[0012] These, and other aspects of the shaft, are described in the following brief and detailed description of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Further aspects of the instant invention will be more readily appreciated upon review of the detailed description of the preferred embodiments included below when taken in conjunction with the accompanying drawings, of which:
[0014] [0014]FIG. 1 is an exploded view of a take-up shaft.
[0015] [0015]FIG. 2 is a side perspective view of the assembled shaft of FIG. 1.
[0016] [0016]FIG. 3 is another side perspective view, partly sectional, of the assembled shaft of FIGS. 1 and 2.
[0017] [0017]FIG. 4 is an enlarged perspective of a portion of the shaft of FIGS. 1 - 3 .
[0018] [0018]FIG. 5 is an exploded view of a take up shaft retaining mechanism.
[0019] [0019]FIG. 6 a is a top view of a take-up shaft retaining mechanism.
[0020] [0020]FIG. 6 b is a front view of a take-up shaft retaining mechanism.
[0021] [0021]FIG. 7 is a side view of a two pronged take-up shaft.
[0022] [0022]FIG. 8 is an exploded view of a take-up shaft, with a rod that may be mounted or disposed by locking with take-up shaft.
[0023] [0023]FIG. 9 is a perspective view of the assembled shaft of FIG. 8.
[0024] [0024]FIG. 10 is an enlarged perspective view of the tab and slot relationship between the rod and the take-up shaft.
[0025] [0025]FIG. 11 is an exploded view of the gear side assembly, or securing mechanism, of the take-up shaft.
[0026] [0026]FIG. 12 is an exploded view of the operator side assembly of the take-up shaft.
[0027] [0027]FIG. 13 is a perspective view of an assembled take-up shaft in the housing.
[0028] [0028]FIG. 14 is a perspective view of a take-up shaft having a rod.
[0029] [0029]FIG. 15 is a perspective view of the take-up shaft of FIG. 13.
[0030] [0030]FIG. 16 is an exploded view of the gear side assembly shown in FIG. 14.
[0031] [0031]FIG. 17 is a perspective view of the take-up shaft and cloth take-up ring.
[0032] [0032]FIG. 18 is a side view of the rod shown in FIG. 14.
[0033] [0033]FIG. 19 is a front view of the cloth take-up ring shown in FIG. 14.
[0034] [0034]FIG. 20 is a side view of the cloth take-up ring shown in FIG. 14.
[0035] [0035]FIG. 21 is an exploded view of a take-up shaft with a rod that is assembled onto the take-up shaft.
[0036] [0036]FIG. 22 is a perspective of the take-up shaft with a fabric assembled between the rod and the take-up shaft.
DETAILED DESCRIPTION OF THE INVENTION
[0037] In FIG. 1, a cylinder cleaning device 100 is shown. In general, the cleaning device 100 includes a frame 10 for holding a cleaning fabric take-up shaft 20 , a cleaning fabric supply shaft 30 , and an inflatable bladder assembly 40 , for pressing cleaning fabric against the cylinder to be cleaned. It is to be understood that any mechanism other than the inflatable bladder 40 , such as a blade, may be used to contact the cleaning fabric with the cylinder to be cleaned.
[0038] More specifically, the frame 10 is removably attachable to a printing press frame (not shown). The frame 10 defines a rigid cartridge housing containing the cleaning fabric take-up shaft 20 and the cleaning fabric supply shaft 30 . The rigid cartridge housing includes two side members 16 and a brace member 18 . The side members 16 include a first pair of sockets 12 for receiving the take-up shaft 20 and a second pair of sockets 14 for receiving the supply shaft 30 . The brace member 18 connects the two side members 16 , enabling the cleaning fabric take-up shaft 20 and the cleaning fabric supply shaft 30 to be attached to the frame 10 prior to insertion into the printing press frame. The rigid cartridge housing also supports the inflatable bladder assembly 40 . Thus, the frame 10 supporting the cleaning fabric take-up shaft 20 , the cleaning fabric supply shaft 30 and the inflatable bladder assembly 40 is inserted and removed from the printing press frame as a complete unit. The frame 10 is constructed using one sheet of material, i.e. aluminum or steel, although in alternate embodiments, the frame 10 includes other metals, alloys or composites generally known in the art, molded plastic, or the like.
[0039] The take-up shaft 20 is used for the winding of cleaning fabric after it has been used to clean the cylinder. The shaft 20 includes a hingeably mounted rod 22 and an axial groove 24 . As illustrated, the rod 22 aligns with the groove 24 so that the rod 22 may be inserted in the groove 24 . Preferably, a magnet is imbedded into the groove 24 to secure the rod 22 in place, although other securing means, such as a latch or adhesive, may be used. The take-up shaft 20 also includes a rectangular extension 26 , which preferably includes an extension of the groove 24 . The extension 26 is engageable with a cleaning cloth advancement mechanism 28 , which serves to rotate the take-up shaft 20 . In general, the cleaning fabric advancement mechanism 28 includes a one-way clutch and an advancement arm, which can be actuated by any number of means, such as a hydraulic piston or motor. The cleaning cloth advancement mechanism 28 may be any of the known advancement mechanisms, such as that described U.S. Pat. No. 5,176,080, herein incorporated by reference, or in U.S. Pat. No. 5,450,792, herein incorporated by reference.
[0040] Depending on the implementation, a take-up shaft 90 is used for the winding of cleaning fabric after it has been used to clean the cylinder. As illustrated in FIG. 7, the shaft 90 includes a support member 92 and two pronged members 94 . The two pronged members 94 protrude from the support member 92 and extend parallel to each other. The take-up shaft 90 also includes a securing mechanism 80 . The securing mechanism 80 for the take-up shafts will be described in greater detail below.
[0041] The supply shaft 30 includes one or more projections 32 extending from the circumference therefrom. The projections 32 are in the form of three wheels spaced along the axis of the supply shaft 30 . The circumference of each wheel 32 extends beyond that of the supply shaft 30 . Although the wheels 32 are in axial alignment, it is to be understood that each wheel 32 may be spaced at different points on the circumference of the supply shaft 30 . Additionally, fewer or more than three wheels 32 may be used. The projections may include one or more ridges extending part of or the entire length of the shaft 30 .
[0042] Cooperating with the supply shaft 30 is a spring loaded securing mechanism 36 , 38 . This mechanism will be described in greater detail with reference to FIG. 4. Also cooperating with the supply shaft 30 is a series of nylon-tipped screws 34 . When the supply shaft 30 is inserted into the opening 14 in the frame 10 , the nylon-tipped screws 34 are tightened around the shaft 30 , thereby supplying a braking force. As will be appreciated by those skilled in the art, such a braking force prevents bunching of cleaning fabric.
[0043] The assembled device 100 is shown in FIGS. 2 and 3. As illustrated, a cleaning fabric supply roll 50 can be inserted on the supply shaft 30 . In general, the supply roll 50 comprises cleaning fabric 52 wound on a cardboard core 54 . The procedure for inserting the supply roll 50 on the supply shaft 30 will be described in greater detail below.
[0044] The supply shaft 30 and the core of the supply roll 50 interlock in a key arrangement. For example, the shaft 30 includes a ridge, and the core include a mating groove.
[0045] A close-up of a socket 14 will now be described in greater detail with reference to FIG. 4. As shown, the securing mechanisms 36 , 38 are secured together with mechanism 38 extending through the socket 14 . Furthermore, the securing member 38 includes a cupped or hollow surface for receiving the end of the supply shaft 30 . Additionally, a U-shaped support 60 is secured to the interior surface of the frame 10 when the securing mechanism 36 is drawn away from the frame 10 , mechanism 38 is partially drawn out of the socket 14 . As discussed in greater detail below, when the mechanism 36 is released, a spring (not shown) draws the mechanism 38 back into the socket 14 and the mechanism 36 back towards the frame 10 .
[0046] [0046]FIG. 5 illustrates a mechanism for securing the take up shaft in place. As shown, an extension, here formed as a wedge, 70 is rotatably secured to the end of the take up shaft 20 by means of a screw 72 or rivet. The securing mechanism also includes a rod 74 having a groove 76 cut therein. The rod 74 is secured to either the frame end or the press frame (not shown) in a position such that when the take up shaft 20 is inserted into the frame 10 , the wedge 70 may be rotated and engaged with the groove 76 . Engagement of the wedge 70 with the groove 76 prevents the shaft 20 from withdrawing axially through the frame 10 .
[0047] Depending on the implementation, the mechanism for securing the take up shaft in place may be as shown in FIG. 6A and FIG. 6B. The take up shaft securing mechanism 80 comprises a rotatable sleeve 82 attached to the end of the take up shaft 20 . As shown, the sleeve has a diameter greater than the socket 12 . Furthermore, the sleeve 82 includes a threaded portion on its interior surface which may engage external threads on the socket 12 . An extension of the take up shaft 20 , which is narrower than the shaft 20 itself, extends through a hole in the center of the sleeve 82 .
[0048] The securing mechanism 80 further includes a knob 88 fixably secured to the extension of the take up shaft which passes through the sleeve 82 . As such, the knob 88 secures the sleeve 82 to the take up shaft 20 while allowing the sleeve 82 to rotate on the extension.
[0049] In operation, a cleaning fabric supply roll 50 is inserted axially onto the supply shaft 30 . Such insertion is relatively easy, as the wheels 32 exert a relatively low friction force against the cardboard core 54 of the supply roll 50 . Additionally, it has been found that the wheels 32 deform the relatively soft cardboard core 54 .
[0050] Once the cleaning cloth supply roll 50 is inserted on the supply shaft 30 , the supply shaft 30 is inserted into the frame 10 . This is performed by inserting one end into the socket 14 not having the securing mechanism 36 , 38 . The other end of the supply shaft 30 is secured into place by first drawing the securing mechanism 36 , 38 away from the supply shaft 30 and frame 10 . The supply shaft 30 is then rested on the U-shaped support 60 . With the supply shaft 30 in position, the securing mechanism 36 , 38 is then released and drawn back towards the supply shaft 30 by the spring. The hollow, cupped end of the mechanism 38 thus engages the end of the supply shaft 30 , thereby securing it in place. It should be noted that the U-shaped support 60 provides the added benefit of limiting axial movement of the supply roll 50 by abutting the cardboard core 54 .
[0051] The take up shaft 20 must also be secured to the frame 10 . To secure the shaft 20 to the frame 10 , the take up shaft 20 is inserted through the sockets 12 until the sleeve 82 abuts the socket 12 . By rotating the sleeve 82 , the threaded section 84 of the sleeve engages the threaded section of the socket 86 , thereby drawing the take up shaft further through the sockets 12 and into an operational position. It should be noted that engagement of the sleeve 82 with the socket 12 secures the take up shaft 20 in place, while allowing rotation of the shaft 20 through either actuation of the advancement mechanism 28 or manual rotation of the knob 88 . With the take up shaft secured in place, the cleaning fabric 52 can be wound through the device 100 and secured to the take up shaft 20 .
[0052] To wind the cleaning fabric 52 through the device 100 , it is drawn off of the supply roll 50 , threaded around the pad 40 , and secured to the take up shaft 20 . It should be noted that when drawing the cleaning fabric 52 from the roll 50 , the roll 50 and supply shaft 30 rotate together. This occurs because the wheels 32 , although having little frictional force axially, have edges that engage the cardboard core 54 and provide a relatively greater radial or angular frictional force. Thus, the cardboard core 54 cannot rotate without also rotating the supply shaft 30 .
[0053] Securing the cleaning fabric 52 to the take up shaft 20 involves first lifting the rod 22 from the groove 24 . The cleaning fabric 52 is then inserted underneath the rod 22 , between the rod 22 and take up shaft 20 . The rod 22 is then reinserted into the groove 24 , thereby securing the cleaning fabric 52 between the rod 22 and take up shaft 20 . The magnet helps retain the rod 22 in the groove. Next, the cleaning cloth 52 is prevented from being drawn out of the groove 24 by rotating the take up shaft 20 approximately one revolution. Such revolution may be performed manually by either grasping the take up shaft 20 or rotating the knob 88 .
[0054] When the supply roll 50 is expended and the used cleaning fabric 52 is completely wound on the take up shaft 20 , the present invention allows easy removable of the used cloth 52 . First, the take up shaft 20 is unsecured from the device. This is done by either rotating the wedge 70 , shown in FIG. 5, out of engagement with the rod 74 , or unscrewing the sleeve 82 , shown in FIG. 6 a , from the threaded socket 12 . Second, the take up shaft 20 is simply drawn out of the socket 12 a few inches. By drawing the take up shaft 20 out of the frame 10 , the used fabric 52 is automatically forced off of the take-up shaft 20 by the force exerted on the fabric 52 by the frame 10 and/or socket 12 . With the take-up shaft 20 drawn out of the frame 10 a few inches, the used fabric 52 is freed from the end of the take-up shaft 20 opposite the securing mechanism. Third, the press operator simply pulls the expended cloth 52 off the take-up shaft 20 in an axial direction. It will be appreciated by those skilled in the art that such removal of the used cleaning fabric 52 represents an improvement over the prior art because no time is taken for the unwinding of the used cleaning fabric.
[0055] The cleaning fabric of the take-up shaft 90 , drawn off the supply roll 30 , is inserted between the two pronged members 94 protruding from the support member 92 of the take-up shaft 90 . The two pronged members 94 retain the cleaning fabric by mechanically locking or pinching the cleaning fabric between the members 94 . The take-up shaft is then rotated approximately one revolution to prevent the cleaning cloth from being pulled out of the space between the pronged members 94 . Such revolution may be performed manually by either grasping the take-up roll 90 or rotating the knob 88 . The take up shaft 90 is secured to the frame in the same manner as described above for the take-up shaft 20 .
[0056] [0056]FIG. 8 shows the components of a fully assembled take-up shaft 800 , having a first member 820 and a second member 822 , wherein the second member may be, but is not necessarily a rod, according to one embodiment of the present invention. As opposed to the rod 22 , mounted or disposed by hinging, of the take-up shaft 20 , the second member 822 , is mounted or disposed to the take-up shaft 820 , by locking to the first member 820 . An exploded view of a gear side assembly 827 , or securing mechanism, is shown, wherein the second member 822 is attached. Also, an exploded view of an operator side assembly 828 is shown, wherein the first member 820 is attached. Additionally, as shown in FIGS. 9 and 10, the first member 820 is attached to the gear side assembly 827 by connecting with the second member 822 .
[0057] [0057]FIG. 9 shows the components of a fully assembled take up shaft 800 , wherein the second member 822 is placed into an axial groove 824 of the first member 820 . A tab 821 is located on the end of the first member 820 that is to be placed into a slot 823 of the second member 822 , and thereby attached to the gear side assembly 827 , or securing mechanism. The other end of the first member 820 attaches to the operator side assembly 828 . The tab and slot connection may contain fewer components, thereby reducing cost of production and improving reliability of repair. FIG. 10 shows a close up view of the tab and slot connection, as described in FIG. 9.
[0058] [0058]FIG. 11 shows the components of the gear side assembly 827 , or securing mechanism, for the take-up shaft 820 of the present invention. The cylindrical end of the second member 822 slides into the cylindrical opening of a wedge 870 . A plate 873 is attached to the cylindrical end of the second member 822 by a screw 872 , thereby immobilizing the gear side assembly 827 , or securing mechanism.
[0059] [0059]FIG. 12 shows the components of the operator side assembly 828 for the take-up shaft 800 of the present invention. The first member has a cylindrical extension 826 that slides into the cylindrical opening of an axial rod 830 , having an axial rod cylindrical extension 831 . The axial rod cylindrical extension 831 passes through a circular opening of a handle 832 and is fastened to the handle 832 with a fastener 833 . A brace 829 slides over the axial rod 830 , and the handle 832 slides over the brace 829 , therefore rendering the operator side assembly 828 immobile.
[0060] [0060]FIG. 13 shows the fully assembled take-up shaft 800 , comprising the first member 820 , the gear side assembly 827 , or the securing mechanism, and the operator side assembly 828 , in the housing 810 . An operator of the fully assembled take-up shaft 800 would operate at the operator side assembly 828 , using the handle 832 . Fabric is secured between the second member 822 and the first member 820 as is described above.
[0061] As shown in FIG. 14, a take-up shaft 1400 has a first member 1420 and a second member 1422 , wherein the second member may be, but is not necessarily a rod. The second member is mounted or disposed to the first member 1420 by a sliding attachment. Both ends of the first member 1420 have a rectangular extension 1421 for connecting purposes. One end of both the second member 1422 and the first member 1420 slide into a cloth take-up ring 1423 , wherein the second member 1422 is above the first member 1420 and both are held immobile within a cylindrical hole of the cloth take-up ring 1423 . The top of the first member 1420 is substantially flat, such that the second member 1422 rests on top of it. In other embodiments of the present invention, the first member 1420 may have an axial groove to secure the second member 1422 . The tab and slot connection shown requires no connecting pieces between the second member 1422 and the first member 1420 .
[0062] [0062]FIG. 15 shows one end of the first member 1420 and the second member 1422 attached to a handle 1424 , for operator use. The other side of the first member 1420 and the second member 1422 , being the same side connected to the cloth take-up ring 1423 , are further attached to a gear assembly 1425 , or securing mechanism. Fabric is secured between the mounted second member 1422 and the first member 1420 as is described above.
[0063] [0063]FIG. 16 shows an exploded view of the gear assembly 1425 , or securing mechanism that is attached to the first member 1420 . A support socket 1426 attaches at one end to a support pin 1428 , having a support pin cylindrical extension 1430 . The other end of the support socket 1426 , attaches to the cloth take-up ring 1423 , as shown in FIG. 14.
[0064] [0064]FIG. 17 is a side perspective of the second member 1422 and the cloth take-up ring 1423 , without the first member 1420 . One end of the second member 1422 attaches to the cloth take-up ring 1423 at an axial groove 1429 (seen in FIG. 19) of the cloth take-up ring 1423 . FIG. 18 is a side view of the second member as shown in FIG. 14, without any attachment to either the first member 1420 or the cloth take-up ring 1423 . One end of the second member 1422 , being the end that is to be attached to the cloth take-up ring 1423 has a larger diameter than a second end of the second member 1422 . The second end of the second member 1422 has an extension 1431 . FIG. 19 and FIG. 20 are a side view and front view of the cloth take-up ring 1423 as shown in FIG. 14, without any attachment to either the second member 1422 or the first member 1420 . The cloth take-up ring 1423 has a first ring 1432 , having a first end and a second end, where the first end is substantially cylindrical and the second end is substantially conic, a second ring 1435 , being substantially cylindrical and having a smaller diameter than the first ring and an axial groove 1429 for attaching to the second member 1422 , where the axial groove 1435 extends through both the first ring 1432 and the second ring 1435 .
[0065] [0065]FIG. 21 shows an exploded view of a take-up shaft 2100 having a first member 2120 and a second member 2122 , wherein the second member may be, but is not necessarily, a rod. The second member 2122 is wedged in an axial groove 2123 of the first member 2120 . The axial groove 2123 is of substantially equal length to that of the second member 2122 . The second member 2122 is fit into the axial groove 2123 of the first member, wherein a fabric 2130 is placed underneath the second member 2122 , as shown in FIG. 22. The weight of the second member 2122 maintains is large enough to maintain enable on a rotation of the second member 2122 about and axis of its length A, without substantial motion in a transverse direction B. No components or fasteners are necessary to attach the second member 2122 to the first member 2120 , or to have the fabric 2130 remain between the second member 2122 and the first member 2120 .
[0066] It should be understood that the above description is only representative of illustrative examples of embodiments and implementations. For the reader's convenience, the above description has focused on a representative sample of all possible embodiments, a sample that teaches the principles of the present invention. Other embodiments may result from a different combination of portions of different embodiments. The description has not attempted to exhaustively enumerate all possible variations. The alternate embodiments may not have been presented for a specific portion of the invention, and may result from a different combination of described portions, or that other undescribed alternate embodiments may be available for a portion, is not to be considered a disclaimer of those alternate embodiments. It will be appreciated that many of those undescribed embodiments are within the literal scope of the following claims, and others are equivalent. | A novel apparatus and method of a take-up shaft used in the cleaning of a cylinder of a printing press. The take-up shaft includes features that allow the securing of a cleaning fabric from a supply roll without the need to physically fix or mount the fabric to the supply roll with screws or other fasteners that could cause the fabric to tear. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates generally to a coupler for wireless communications, and more particularly to the use of a novel air-core or dielectric core coupler as a matching device to the characteristic impedance of the air for a transmitter and receiver for wireless communications.
A well-known problem in wireless communications concerns the effects of reflections of a transmitted signal off of the walls of buildings, people, etc. on the transmitted signal as in propagates through the air. These reflected signals cause notches that come and go in the bandwidth where communication takes place, thus degrading transmitted signals. Any such degradation of transmitted signals in wireless communications are extremely costly because it will limit the usage of bandwidth which will result in slower communication speeds and in certain areas the communication devices will not work or will work poorly.
Most of the work to find solutions to the problems of signal losses due to reflected signals has focused on digital signal processing techniques such as Spread Spectrum and CDMA. In Spread spectrum techniques, the bandwidth of a transmitted signal is spread over a large range of bandwidth to communicate the same information in several frequencies. This way, notches in the communications bandwidth will not stop communication to everywhere. The drawback with this technology is that the need to use a wide bandwidth and the interference that is generated from the transmitter and from reflections can result in a complete inability to communicate.
The CDMA technology uses a single carrier frequency and is capable of detecting reflected signals in delayed time sequence. In theory, this should work fine, but, in reality, very fast sampling is required as well as the ability to detect very weak signals. This means a very high price today for effective communications. Also, due to non-real-time communication detection, this technology is probably limited to a couple of MBps transmission speed.
Moreover, regardless of the utility of techniques such as CDMA, reflected signals will still cause notches in the communications band of interest as a result of the basic physics that limits the antenna as a matching device for transmitters and receivers. The characteristic impedance change in the air from walls and other objects reflects back to the transmitter and receiver, which causes notches in the communications bandwidth. The two impedances (air and transmitter/receiver) need to be matched to each other to avoid notches in the communications bandwidth.
There is thus a need for a coupler that is capable of matching the impedance of the air with the impedance of a wireless transmitter and receiver in order to eliminate notches in the communications bandwidth.
SUMMARY OF THE INVENTION
Briefly stated, in a first embodiment, the present invention is a communications apparatus for transmitting electric or electromagnetic signals over air having a characteristic impedance. The communications apparatus comprises:
a transmitter having an output impedance, the transmitter for transmitting the electric or electromagnetic signals at a preselected frequency; and
a coupler connected to the transmitter, the coupler comprising a transformer having a non-magnetic core, the transformer communicating the electric or electromagnetic signals to the air, the coupler matching the output impedance of the transmitter to the characteristic impedance of the air.
In a second embodiment, the present invention is a communications apparatus for receiving electric or electromagnetic signals from air having a characteristic impedance. The communications apparatus comprises:
a receiver having an input impedance, the receiver for receiving the electric or electromagnetic signals at a preselected frequency; and
a coupler connected to the receiver, the coupler comprising a transformer having a non-magnetic core, the transformer receiving the electric or electromagnetic signals from the air, the coupler matching the input impedance of the receiver to the characteristic impedance of the air.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing summary, as well as the following detailed description of preferred embodiments of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings embodiments that are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings, like numerals are used to indicate like elements throughout. In the drawings:
FIG. 1 is a graphical illustration of the characteristic impedance of the air-core coupler of the present invention;
FIG. 2 is a combination schematic and block diagram of an air-core wireless transmitter/receiver according to a first preferred embodiment of the present invention;
FIG. 3 is a combination schematic and block diagram of an air-core wireless transmitter/receiver according to a second preferred embodiment of the present invention;
FIG. 4 is a combination schematic and block diagram of an air-core wireless transmitter/receiver according to a third preferred embodiment of the present invention;
FIG. 5 is a combination schematic and block diagram of an air-core wireless transmitter/receiver according to a fourth preferred embodiment of the present invention;
FIG. 6 is a combination schematic and block diagram of an air-core wireless transmitter/receiver according to a fifth preferred embodiment of the present invention; and
FIG. 7 is a combination schematic and block diagram of an air-core wireless transmitter/receiver according to a sixth preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
My co-pending U.S. patent application Ser. No. 09/344,258 (“the '258 Application”), now U.S. Pat. No. 6,104,707, discloses a novel phase shift linear power, phone, twisted pair, and coaxial line coupler for both transmission and reception. The phase shift linear coupler comprises a novel air-core or dielectric core transformer which can be used for phone line, coaxial, LAN and power line communication through power line transformers. The phase shift linear coupler further comprises an associated coupling capacitor network in order to achieve resistive matching to approximately the lowest known value of the line characteristic impedance and to maximize stable signal transmission onto the line. This resonance effectively creates a band pass filter at carrier frequency. The disclosure of the '258 Application is incorporated herein by reference in its entirety.
The present invention uses the novel phase shift linear coupler of the '258 Application to match the impedance of the air with the impedance of a wireless transmitter and receiver in order to eliminate notches in the communications bandwidth.
The importance of the coupler of the present invention is that it can remain a matching device to the characteristic impedance of the air. As in the '258 Application, the coupler of the present invention comprises an air-core or dielectric-core transformer and an optional coupling capacitor, Ceq. Any impedance change on the primary winding of the transformer does not reflect much to the secondary winding of the transformer and vice versa. Therefore, the only impedance that will be seen by the air is the primary winding, either alone or resonated with the capacitor Ceq. Such serial or parallel resonance will create a low impedance, which will be close to 1 ohm. As the frequency is increased, the impedance will increase also to approximately 100-200 ohm, depending on which impedance is the best to match the air characteristic impedance, and how much bandwidth is needed.
For example, FIG. 1 shows the coupler characteristic impedance to the air. If the air impedance is 100 ohm at F 1 then 6 dB matching from the coupler will be from 50 ohm (F 4 ) to 200 ohm (F 3 ), which will cover a wide bandwidth from F 3 to F 4 . By contrast, if the air characteristic impedance is only 10 ohm, the 6 dB matching will be from 5 to 20 ohm, resulting in a smaller bandwidth. For this reason, there is a wider bandwidth outside of homes and buildings than inside, where the air characteristic impedance is smaller. Lowering the coupler impedance can result in wider bandwidth matching in low characteristic impedance (e.g., 10 ohm) air.
As discussed in the '258 Application, a significant advantage of the coupler of the present invention is the phase linearity achieved. The matching produced by the coupler of the present invention can open up wide linear bandwidth communication over air at rates of up to several Gbps.
As in the '258 Application, the coupler of the present invention preferably has two coaxial solenoids or air-coils of different diameter with primary and secondary inductances L 1 and L 2 respectively. Both L 1 and L 2 are inductively and capacitively coupled creating an air-core transformer. Preferably, the air-gap is filled with resin, which reduces inductive loading effects from the coupler secondary to the primary by using the capacitance created in the air core transformer. The size of the gap is selected to reduce inductive loading effects from the coupler secondary to the primary. A coupling capacitor, Ceq, is also preferably provided.
Inductive loading effects from the secondary to the primary of the air-core transformer are minimized at the transmit/receive frequency. The effective transceiver input impedance, as seen at the secondary (inside coil), can be designed to be 55 OHM inductive. The effective air and reflected devices input impedance, as seen at the primary (outer coil), is equal to an impedance that is created by the resonance of the coupling capacitor Ceq and the primary inductance at a given frequency. Its value can be chosen to optimally match the air characteristic impedance (Zo).
Referring now to the drawings, wherein like numeral designate like or corresponding parts throughout each of the several views, there is shown in FIG. 2 a first preferred embodiment of an air-core transmitter/receiver 10 according to the present invention. The air-core transmitter/receiver 10 includes a wireless transmitter or receiver 12 , an air-core transformer 14 , a tuning capacitor (Ceq 1 ) 16 , and an antenna 18 . Any wireless transmitter or receiver 12 can be used with the present invention, for both mobile units and base stations.
The air-core transformer 14 has a novel, air coil structure which functions as a respective inductively and capacitively coupled air-core transformer for both transmission and reception. The air-core transformer 14 is phase shift linear and comprises a primary winding 20 and a smaller, coaxial secondary winding 22 . The primary winding 20 has a winding diameter 2 R which is greater than a diameter of the secondary winding 2 r. Accordingly, an air gap is created between the primary winding 20 and the secondary winding 22 . Of particular significance is the fact that both the primary and secondary windings 20 , 22 of the air-core transformer 14 can have about the same number of turns (designated by N 1 =N 2 ), and are thus at a 1:1 ratio. Accordingly the transmitter or receiver 12 does not require a high transmission voltage. Further Ceq 1 16 is set to resonate with the primary winding 20 at the carrier frequency FA, thus creating a band pass filter at the carrier frequency FA. This maximizes the current at the carrier frequency FA.
The transmitter or receiver is connected to the secondary winding 22 of the air core transformer 14 , which will match approximately 50 OHM at the frequency of interest FA. The primary winding 20 of the air-core transformer 14 is connected in series with Ceq 1 16 and the antenna 18 . The primary winding is designed to match the most common characteristic impedance of the air where the wireless transmitter/receiver will be used. The primary winding 20 is also preferably connected to a ground 24 . Although it is not necessary to ground the primary winding 20 , it is desirable to do so, because the efficiency of the transmitter/receiver 12 will be increased.
Any antenna 18 may be used with the present invention, although the antenna 18 is preferably designed to match the air core transformer 14 and the desired transmission or reception frequency FA.
For higher frequencies (e.g., 200 Mhz-500 GHz), the structure of the air-core or dielectric core transformer differs from that of the '258 Application. Such alternative transformer designs are also preferable for use in the present invention with wireless transmitters/receivers where small size is important—e.g., particularly in mobile units. The coupler may no longer be two coaxial solenoids or air-coils of different diameter wrapped with magnet wire, but instead is much smaller and resembles a chip which is filled with any type of plastic or non-conductive material, such as resin, glue material, ceramic or any other hard non-conductive material (“chip material”). The coupler preferably comprises very thin conductive plates separated by chip material. The plates are preferably made from copper, but can also be made from silver, gold, or any other conductive material, whether it is active or passive. The plates can be any shape (e.g., square, rectangular, round, etc.) but are preferably circular. The size of such layered air-core transformers will depend on the frequency of usage. For example, a 30 GHz coupler primary diameter will be less then 1 millimeter, the layer thickness will be less then about 0.1 millimeter, which results in about a 0.3 nH inductance. Similarly, the thin rectangular copper plate sizes will be around a couple of millimeters long, 0.1 millimeters thick and the primary and secondary inductors will be about 0.5 millimeters away from each other, on top of each other. Consequently, such devices will look like a very small capacitor. However, the present invention uses the end to end inductor values to resonate the capacitor for matching the power line characteristic impedance.
Alternatively, the plates can be formed directly in a chip by deposition of metallic layers or through doping silicon. Doped silicon is conductive when it is active—e.g., a DC level of voltage turns on a transistor to make it an active device. Thus, the plates when formed of doped silicon may take the form of some type of active device such as a transistor or a diode. Of course, it will be appreciated that other designs of air-core or dielectric-core transformers can be used without departing from the spirit or scope of the present invention. For example, a piece of coax cable can be used as an air-core transformer. The shield of the coax cable is the primary of the transformer and the inside wire is the secondary of the transformer. This coax type of air-core transformer can be used for very high frequency communications above 500 MHz. Similarly two copper or iron pipes (or aluminum or copper foil) can be placed inside each other. The outside pipe or foil is the primary of the air-core transformer, and the inner pipe or foil is the secondary. This design can also be used over 100 MHz.
One of ordinary skill in the art will also appreciate that other more simple integrated circuits can also be used to create transformers for use in the coupler of the present invention. Today's integrated circuits using active transistors can simulate and/or create an aircore transformer that can have the necessary inductance and capacitance values to work exactly as a regular air-core transformer.
Although the structure of the couplers as described above differs from that disclosed in the '258 Application, the function of the coupler is the same. The plates (or pipes or foils) of the coupler are inductively and capacitively coupled creating an air-core or dielectric-core transformer. The coupling of the primary and secondary of the transformer varies with frequency, however. The primary and secondary are coupled about equally magnetically and electrically (i.e., capacitively and inductively coupled) below 100 MHz of frequency and more inductively coupled (magnetically) at frequencies higher than 100 MHz. At frequencies on the order of 100 GHz, the primary and secondary of the transformer will be mostly inductively coupled.
Turning to FIG. 3, a second preferred embodiment of the air-core transmitter/receiver 10 according to the present invention is shown. The second preferred embodiment is identical to the first preferred embodiment except as described below. As shown in FIG. 3, no antenna 18 is used in this embodiment, but rather the serial tuning capacitor (Ceq 1 ) 16 serves as the antenna. The serial tuning capacitor (Ceq 1 ) 16 will resonate with the primary winding 20 of the air-core transformer 14 at the communications frequency of interest FA.
In a third preferred embodiment of the air-core transmitter/receiver 10 of the present invention, which is identical to the first preferred embodiment except as discussed below, a parallel tuning capacitor (Ceq 1 ) 16 is used rather than a serial tuning capacitor (Ceq 1 ) 16 . As shown in FIG. 4, the tuning capacitor (Ceq 1 ) 16 is connected in parallel with the primary winding 20 of the air-core transformer 14 . The primary winding 20 is also connected to the antenna 18 . The primary winding 20 resonates in parallel with Ceq 1 16 at the frequency of interest FA.
Turning to FIG. 5, a fourth preferred embodiment of the air-core transmitter/receiver 10 according to the present invention is shown. The fourth preferred embodiment is identical to the third preferred embodiment except as described below. As shown in FIG. 5, no antenna 18 is used in this embodiment, but rather the parallel tuning capacitor (Ceq 1 ) 16 serves as the antenna. The parallel tuning capacitor (Ceq 1 ) 16 resonates with the primary winding 20 of the air-core transformer 14 at the communications frequency of interest FA.
In a fifth preferred embodiment of the air-core transmitter/receiver 10 of the present invention, which is identical to the first preferred embodiment except as discussed below, no tuning capacitor (Ceq 1 ) 16 is used. As shown in FIG. 6, the antenna 18 is connected directly to the primary winding 20 of the air-core transformer 14 . The primary winding 20 resonates at the frequency of interest FA.
Finally, turning to FIG. 7, a sixth preferred embodiment of the air-core transmitter/receiver 10 according to the present invention is shown. The sixth preferred embodiment is identical to the fifth preferred embodiment except as described below. As shown in FIG. 7, no antenna 18 is used in this embodiment, but rather the primary winding 20 of the air-core transformer 14 serves as the antenna. The primary winding 20 of the air-core transformer 14 resonates at the communications frequency of interest FA.
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above, without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiment disclosed, but it is intended to cover modifications within the spirit and scope of the present invention. | An apparatus for communication of electric or electromagnetic signals over air includes a transmitter or receiver and a coupler. The coupler has a capacitive circuit connected with an air-core or dielectric-core transformer. The capacitive circuit resonates with the transformer at a preselected frequency. The coupler eliminates noise and is matched to the characteristic impedance of the air at the preselected frequency, which linearizes communication and allows high-speed data and voice communication over long distances. | 7 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a road traffic signal light. Specifically, the present invention relates to an LED signal light for road traffic that is distinguishable by both persons with normal vision and persons with color vision deficiency.
[0002] Presently, signal lights, using a light bulb as a light source transmitting light through colored filters of red, yellow, and green, are being replaced by LED signal lights constituted of collections of LED elements of high chromaticity and luminance of red, yellow, and green lights.
[0003] An LED signal light, arranged by assembling LED elements that emit light of the same luminance and chromaticity, has a high level of visibility in comparison to a light bulb signal light. It is rapidly spreading in use for the excellence in preventing wash-out caused by morning and afternoon sunlight, resulting from reflected lights against inside mirror.
[0004] Meanwhile, the colors of a road traffic signal light are mainly defined based on the visible ability and perception for persons with normal color vision, and adequate considerations have not necessarily been made for color deficient persons who used to distinguish kinds of signals according to brightness differences in case of light bulb type. Especially, since both the luminance and chromaticity in case of LED signal lights are constant and maximize, it has been pointed out that yellow and red appear the same to color deficient persons.
[0005] As an LED signal light that is distinguishable by color deficient persons, there is a traffic signal light with the arrangement shown in FIG. 9 . With the traffic signal light 101 , each of lamps 102 , 103 , and 104 has a holding plate, holding a plurality of light emitting diodes, and each of lamps 102 , 103 , and 104 performs lighting display of a different shape according to the configuration of the plurality of light emitting diodes. Specifically, the red lamp 102 displays an X shape by the plurality of light emitting diodes, the yellow lamp 103 displays a triangular shape by lighting of the plurality of light emitting diodes, and the green lamp 104 displays a circular shape by lighting of the plurality of light emitting diodes to enable color deficient persons to distinguish according to lighting shape (see Patent Document 1).
[0006] Also, a road traffic signal light shown in FIG. 10 is constituted of plural types of small light sources as 105 and 106 that differ in wavelengths to form a green signal light emitting surface 107 , where 108 is a partially enlarged view of the light emitting surface 107 . By providing a single green signal light as a whole, distributing of the small light sources 105 and 106 , a color deficient person is made to recognize a green signal light (see Patent Document 2).
[0007] Patent Document 1: Japanese Published Unexamined Patent Application No. H10-3596 (Abstract, FIG. 1)
[0008] Patent Document 2: Japanese Published Unexamined Patent Application No. H8-138192 (Abstract, FIG. 1)
[0009] Although with the invention of Patent Document 1, the red, yellow, and green lamps of the traffic signal light are lighted in the X, triangular, and circular shapes to enable a color deficient person to distinguish which lamp is lighted, for a normal vision person, such a traffic signal light is strangely perceived from a normal signal light, and is specifically recognizable as a design for the color deficient person.
[0010] Also, the chromaticity and luminance ranges of a traffic signal light are defined by regulations, and when lamps are lighted in the X, triangular, and circular shapes, each lighting area becomes much smaller than a normal signal light area. Therefore, it becomes extremely difficult to secure the prescribed luminance level. It is thus considered that under daylight, a color deficient person may have difficulty in distinguishing which of the red, yellow, and green lamps is lighted.
[0011] The invention of Patent Document 2, in order to alleviate misrecognition of a red signal and a green signal by a protan, assembles small light sources of plural types that differ in main wavelength to provide a green signal light, in which lights of no less than two colors are mixed.
[0012] Here, among color deficient persons, there are protans and deutans, and although Patent Document 2 described that the number of protans is the highest, in correct actuality, the number incidence of deutan deficiency is the highest and is said to be approximately three times the number of protan deficiency. Also, the document is potentially misleading in that both protans and deutans misrecognize green and red signals. A green signal in Japan, a chromaticity closer to blue is applied for the color deficient person to help distinguishing green from red. Actually, they tend to have a rather high sensitivity to blue, so that erroneous perception between red and yellow is more of a problem in reality.
[0013] The signal light of Patent Document 2 is thus aimed at alleviating misrecognition of green by just protans and is not aimed at color deficient persons in general. Also, even if misrecognition is alleviated for just green, as long as the problem of distinguishing between red and yellow remains, the problem of erroneous perception by color deficient persons is not resolved.
[0014] The present invention has been made in view of the above points and an objective thereof is to provide a red or a yellow LED signal light with a symbolic pattern based on chromaticities that are distinguishable by color deficient persons even from a certain distance without causing color mixing as a whole.
SUMMARY OF THE INVENTION
[0015] To achieve the above objective, the present invention provides a red LED road traffic signal light with a set of light emitting LED elements different in chromaticity from the red LED elements.
[0016] Here, color deficient persons are classified according to the three patterns as protan, deutan, and tritan deficiency. Confusion lines for a protan defect, deutan defect, and tritan defect are shown in FIGS. 11A , 11 B, and 11 C.
[0017] With the color confusion lines for the protan and deutan deficiency ( FIGS. 11A and 11B ), red and yellow lie along the same color confusion line and are thus extremely difficult to distinguish by protan and deutan. Meanwhile, with the confusion lines for the tritan defect ( FIG. 11C ), because red, yellow, and green do not lie on the same line, the respective colors are distinguished. The protan defect and the deutan defect are thus the subjects of color deficiency in regard to signal lights.
[0018] Ranges of red, yellow, and green approved for signal lights in a xy coordinate system are defined as shown by the chromaticity diagram by the Commission Internationale de l clairage (CIE) in FIG. 12 . In this xy coordinate system, although red and yellow lie along a confusion line, green is set in a coordinate area, within a green designation area, that is close to blue and is shifted from the confusion lines for protans and deutans. Thus, for protans and deutans, whereas a green light is distinguishable, distinction between red and yellow is difficult.
[0019] Thus, with the present invention, in order to enable distinction between red and yellow, distinguishing LED elements of a purplish color, differing in chromaticity from the red LED elements, are mixed in the red lamp and configured, for example, in an X-like pattern. As the set of illuminant colors, red appears as a dull brown color and the purple is clearly perceived as a bright blue color to a color deficient person, so that the vision difference is greater than a normal vision person due to the illuminant color hue difference.
[0020] Furthermore, the color emission of the distinguishing LED elements is a purplish color, such as purple, reddish purple, bluish purple, etc. which is a similar color with respect to red, so it is thus difficult from a distance to distinguish a purplish color from red for a normal vision person. Therefore, an LED signal light that does not give an odd impression for both color deficient and normal vision persons can be provided.
[0021] Also, in order to achieve the above objective, the present invention provides an LED road traffic signal light that is a red LED signal light, constituted of a set of red light emitting LED elements with an X-like pattern that is lower in luminance than the surrounding red LED elements.
[0022] A color deficient person, because of having difficulty distinguishing color hues, tends to be rather sensitive to lightness and saturation. A color deficient person, who has difficulty distinguishing different hues, is thus much better than normal vision persons in the ability to distinguish brightness of similar colors.
[0023] Thus, with the present invention, by configuring red distinguishing LED elements, made lower in luminance than the surrounding red LED elements, in, for example, an X-like pattern in the set of red LED elements to enable a color deficient person distinguishing of red. Since a color deficient person is more sensitive to brightness differences than a normal vision person, the distinguishing LED elements and the other LED elements are thereby perceived more clearly than a normal vision person.
[0024] Also, in order to achieve the above objective, the present invention provides an LED road traffic signal light that is a red LED signal light, constituted of a set of red light emitting LED elements with an X-like pattern that differs in chromaticity from the red LED elements and is made lower in luminance than the surrounding red LED elements.
[0025] Here, by configuring the distinguishing LED elements of a purplish color that differ in chromaticity from the surrounding red LED elements in an X-like pattern, for example, and by making the distinguishing LED elements lower in luminance, color deficient persons are able to distinguish the color of the signal light from a standard distance of 100 m required by the Commission Internationale de l clairage (CIE).
[0026] With the present invention, by configuring the distinguishing LED according to a pattern (for example, an X-mark) in a red LED signal light and making the distinguishing LED elements be of a purplish color, the emitting light can be chromatically recognizable by the color deficient persons (protan and deutan), and an LED signal light can be provided for both normal vision persons and color deficient persons without giving an odd impression to normal vision persons.
[0027] Also, by forming, in the LED element set of the red LED signal light, the distinguishing LEDs that are made low in luminance than the set of other LED elements and configured according to a pattern (for example, an X-mark) to enable clear recognition by color deficient persons, an LED signal light can be provided that can be distinguished by both normal vision persons and color deficient persons without giving an odd impression to normal vision persons.
[0028] Also, by forming, in the LED element set of the red LED signal light, the distinguishing LED emitting light of a chromaticity that can be recognized clearly by color deficient persons (protan and deutan), made low in luminance than the set of other surrounding LED elements, and is configured according to a pattern (for example, an X-mark) enables color deficient persons clear recognition for distinguishing between yellow and red LED signals even from a distance of 100 m.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1 is an explanatory sectional view of Embodiment 1 of an LED road traffic signal light to which the present invention is applied;
[0030] FIG. 2 is an explanatory view of an example of a configuration of distinguishing LED elements of a purplish color in a red LED signal light to which the present invention is applied;
[0031] FIG. 3 is a xy chromaticity diagram of colored light in the red LED signal light to which the present invention is applied;
[0032] FIG. 4 is a photograph of a lighted state of the configuration of LED elements in the red LED signal light shown in FIG. 2 as viewed by a normal vision person;
[0033] FIG. 5 is a photograph resulting from a computer simulation using authorized software for simulating the view of a color deficient person for the lighted state shown in FIG. 4 ;
[0034] FIG. 6 is an explanatory view of a configuration of surrounding red LED elements in a red LED signal light according to Embodiment 2 to which the present invention is applied;
[0035] FIG. 7 is an explanatory view of a configuration of distinguishing LED elements in a red LED signal light according to Embodiment 2 to which the present invention is applied;
[0036] FIG. 8 is a graph comparing the level of recognition for distinguishing LED elements configured in an X-shape by color deficient persons and normal vision persons at a position of 100 m rectilinear distance from a traffic light;
[0037] FIG. 9 is an explanatory diagram of an example of a conventional traffic signal light for color deficient persons;
[0038] FIG. 10 is an explanatory diagram of another example of a conventional traffic signal light for color deficient persons;
[0039] FIG. 11 shows the diagrams of isochromatic color confusion lines for protan, deutan, and tritan deficiency; and
[0040] FIG. 12 is a diagram of standard chromaticity coordinates according to traffic regulations.
DETAILED DESCRIPTION OF THE INVENTION
[0041] To further the understanding of the present invention, embodiments of the present invention shall now be described with reference to the drawings.
Embodiment 1
[0042] FIG. 1 is an explanatory sectional view of an example of an LED road traffic signal light to which the present invention is applied, and FIG. 2 is an explanatory view of an example of a configuration of LED elements in the red LED signal light.
[0043] With the LED signal light 1 shown here, a plurality of red LED elements 3 is positioned in parallel on a printed circuit board 2 , and a colorless, transparent or lightly colored transparent lens cover 4 is fitted in front of the LED elements.
[0044] The set of LED elements 3 is lighted, unlighted, and made to flash by an emission controller (not shown) and each LED element can be adjusted in luminance freely.
[0045] The red LED elements 3 are configured in a circular shape on the circular printed circuit board 2 , and the distinguishing LED elements 5 are configured in an X-shape within the set of red LED elements 3 .
[0046] The distinguishing LED elements 5 are used either full color LEDs emitting the light of reddish purple, purple, bluish purple and other purplish color of a chromaticity that can be distinguished readily by color deficient persons, or LEDs of a designated chromaticity that can be distinguished from a maximum distance at a certain range without causing color mixing.
[0047] A full color LED is an LED element, with which lights of the three primary colors of red, green, and blue are emitted within a single LED element, so that no less than 24 colors can be produced by mutually mixing these colors.
[0048] Thus, by configuring the full color LED elements, which have been controlled to emit a reddish purple, purple, or bluish purple color at the same current voltage in the X-shape within the red LED elements, the reddish purple, purple, or bluish purple color selected lights up in the X-shape within the set of red LED elements.
[0049] The emission color of the distinguishing LED elements is set to a purplish color, such as reddish purple, purple, or bluish purple as shown in FIG. 3 , because the chromaticity of reddish purple, purple, and bluish purple are contained in a portion A of the chromaticity coordinates for colored light that contains xy coordinates of red as the signal light.
[0050] Within the xy coordinate range of the portion A in FIG. 3 , reddish purple is the closest to red followed by purple and bluish purple. In this case, while the easiness of distinction is in the order of bluish purple, purple, and reddish purple by normal vision persons, all of these can be recognized as being distinct in chromaticity for color deficient persons from that of the other red LEDs, and the distinction is further enabled from a longer distance by intensifying a bluish tint.
[0051] A state of lighting by the configuration of LED elements in the red LED signal light shown in FIG. 2 as viewed by a normal vision person is shown in FIG. 4 . In this case for normal vision persons, an LED signal light with the distinguishing LED elements can be provided in the manner that do not give an odd impression and indistinguishable from a certain distance. This is because these emitted distinguishing colors as purple, reddish purple, and bluish purple are a similar and associated color to surrounding red.
[0052] A computer simulation of how the signal light is perceived by color deficient persons, based on the lighting state shown in FIG. 4 , is shown in FIG. 5 . In this case, the red color of the red LED elements disappears as being a dull brown, on the contrary the distinguishing LED elements of the purplish color turns out to appear a bright blue. Thus, the distinguishing LED elements configured in a pattern can be distinguished more clearly by the apparent hue difference.
Embodiment 2
[0053] FIG. 6 shows a configuration of LED elements in a red LED signal light to which the present invention is applied.
[0054] Here, the red LED elements 3 are configured in a circular shape on the circular printed circuit board 2 , and the distinguishing LED elements 5 are configured in an X-shape within the set of red LED elements 3 .
[0055] The distinguishing LED elements 5 are the same kind of other red LED elements, and by the emission controller, the luminance of the LED elements configured in the X-shape is lowered to the performance level as much as approximately the 20% as the limit compared to the luminance of the other surrounding LED elements.
[0056] Color deficient persons can distinguish a sensitive luminance difference than normal vision persons, so that they can perceive the lighting of the LED elements configured in the X-shape as a brightness difference, while normal vision persons are hardly noticeable.
Embodiment 3
[0057] FIG. 7 shows a configuration of LED elements in a red LED signal light to which the present invention is applied.
[0058] Here, the red LED elements 3 are configured in a circular shape on the circular printed circuit board 2 , and the distinguishing LED elements 5 are configured in an X-shape within the set of red LED elements 3 .
[0059] The emission color of the distinguishing LED elements 5 is set to purple, reddish purple, bluish purple or other purplish color that is a similar color with respect to red, and by the emission controller, the luminance of the LED elements configured in the X-shape is lowered to the performance level as much as approximately the 20% as the limit compared to the luminance of the other surrounding LED elements.
[0060] The distinguishing LED elements 5 are thus effective by using full color LEDs of a varying chromaticity as reddish purple, purple, bluish purple, or other purple color that can be readily perceived by color deficient persons, and by utilizing the effective combination of “chromaticity difference” and “luminance difference” that appealed a significant statistical difference in perceptible distances between color deficient persons and normal vision persons.
[0061] An experiment was conducted in a time zone from 1:00 P.M. to 4:00 P.M., when direct sunlight will not hit the LED panel, to examine whether there is a significant difference in the color recognition by color deficient persons and normal vision persons from a position of 100 m rectilinear distance from a traffic light. The underlying methods were of recognizing luminance differences and of recognizing the various combinations of chromaticity and luminance differences for distinguishing LED elements configured in the X-shape.
[0062] For considering the presence or non-presence of astigmatism, a sample set consisting of 24 normal vision persons and seven color deficient persons (from weak to strong deutan deficiency) of ages from 21 to 82 and eyesight ranges from 0.5 to 2.0 was applied. Because it is known that protan deficiency is much fewer in number and recognizes red a much darker color than deutan deficiency, the contrast of the X-mark within a red LED signal light is more emphasized in the perception by protan. Accordingly, with the methods of the present experiment, protans exhibited higher numerical values than the data acquired from deutans. The present results using deutans thus exhibited numerical values on the safe side.
[0063] Tritans do not have problems in distinguishing signal lights.
[0064] As can be seen from FIG. 8 , which is a graph showing the proportion of persons that could see the X-mark from 100 m, color deficient persons exhibited a recognition rate of 100% while normal vision persons exhibited 24% in the examination conducted in six stages (patterns 1 through 6 ), where lightness difference in an X-mark was decreased stepwise from a conspicuous level. These examination results showed that color deficient persons were more sensitive to brightness difference than normal vision persons.
[0065] In the proceeding examination, using four stages of combination (patterns 8 through 11 ) as to differences in chromaticity and luminance, the recognition rate was 93% for color deficient persons and only 1% for normal vision persons. With this method of combining chromaticity and luminance differences, the luminance difference was adjusted to be lower than in the method employed only the luminance difference. The degree of compensation by color to luminance level was examined. It was found that as the blue tint color was increased, the recognizable distance increased gradually even when the luminance difference was lessened with normal vision persons.
[0066] With the method employing just the luminance difference, at the stage of pattern 6 , that is, the luminance of the distinguishing LED elements configured in the X-shape being set to approximately ⅓ to ⅕ compared to the luminance of the surrounding LED elements, the recognition rate of color deficient persons was 100%, while the normal vision persons were unable to detect at all, exhibiting a recognition rate as 0% that achieved the underlying objective.
[0067] With the method combining chromaticity and luminance differences, at the stage of pattern 10 , that is, the distinguishing LED elements were bluish purple in chromaticity and the luminance of the distinguishing LED elements was set to approximately ½ of the surrounding LED elements, the recognition rate of color deficient persons was 100%, while the normal vision persons were unable to detect at all exhibiting a recognition rate as 0%. The underlying objective was thus achieved.
[0068] The above results showed that the phenomenon existed with the method employed only a luminance difference, where all of the color deficient persons could distinguish the X-mark from the distance of 100 m, and none of the normal vision persons could. The distance is prescribed by the Commission Internationale de l clairage (CIE) as the requirement of the color recognition for signal light. The proportion of normal vision persons that could distinguish, however, tended to increase when the luminance difference level is wider than the pattern 6 . Meanwhile, using the method of combining chromaticity and luminance differences, the phenomenon where only the party of normal vision persons could not distinguish was observed over a wider range of combinations due to the synergistic effect of chromaticity and luminance. The stability of the prospective effect can thus be expected in the implementation.
[0069] Although the configuration pattern of the distinguishing LED elements does not need to be the X-shape, and any pattern configuration enabling the lighting and flashing of the red signal light distinguishable from others may be employed. Because the X-shape universally expresses the meaning of O, it is preferable in that when it is displayed inside a red signal light, color deficient persons can instantly recognize it to mean: “stop.”
Description of the Symbols
[0070] 1 LED signal light
[0071] 2 printed circuit board
[0072] 3 red LED element
[0073] 4 transparent lens cover
[0074] 5 distinguishing LED element | An LED road traffic signal light equipped with symbol patterning by chromaticity where a color-blind person can distinguish between red and yellow LED signal lights even at a predetermined distance without causing entire mixture discoloring. A red LED signal light comprising a group of LED elements emitting red light, wherein the group of LED elements is mixed with an identification LED element having a chromaticity different from that of the red LED element, or mixed with an identification LED element having a different luminance, or mixed with an identification LED element combining different chromaticity and luminance, thus constituting an LED road traffic signal light which can be distinguished by both physically unimpaired person and color-blind person. | 5 |
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/932,174, filed May 30, 2007, and entitled “Modified Artificial Rock Climbing Arrangement Adapted For Water Environment,” which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to recreational devices and, more particularly, pertains to the adaptation of an artificial rock climbing arrangement combined with water sports equipment.
BACKGROUND OF THE INVENTION
[0003] Both rock climbing and water sports have increased in popularity tremendously over the last few decades, and with this increase, artificial rock climbing walls and water sports equipment have become quite popular.
[0004] Artificial rock climbing walls allow climbers to practice and hone their skills, and allow beginners to experience rock climbing in a safe environment away from dangerous conditions such as high elevation, loose rocks, etc., that exist while climbing actual rock formations. In addition, artificial rock climbing walls allow purchasers of climbing boots, harnesses, and other equipment to test these articles in a store prior to purchase. Hence, artificial rock climbing walls are becoming commonplace for indoor gymnasiums, resorts, climbing equipment retail stores, and the like. In the past few years, water-based artificial rock climbing walls have begun to take root as a water sports activity, more particularly with residential swimming pools, high schools, colleges, community pools, and lake residents.
[0005] A typical artificial climbing structure will have modular panels constructed of plywood, fiberglass, or other composite material with T-nuts inserted through or molded in the panels. The T-nuts allow components called climbing holds to be affixed to the climbing surface in a manner which defines a climbing route. These climbing holds are often threadably fastened to the T-nuts so that the holds can be added, removed or changed to vary the features and difficulty of ascending the artificial wall. The climbing holds are typically made of resin-concrete, and can be shaped as desired. For example, an easy hold would provide a large external ledge, which is easily grabbed or stepped on. A more difficult hold will only extend slightly from the climbing surface, making it more difficult for the climber to support their weight. Today's climbing holds serve a functional, decorative and an entertainment purpose.
[0006] More recent advancements and climbing wall structures have enhanced the look and feel of the climbing surface. Textured fiberglass panels having molded features that more nearly approximate those of natural walls are also now available. The molded panels incorporate T-nuts or other hold attachments structures so that the difficulty of the various routes can be changed after the panels are assembled. Alternate artificial rock climbing structures make use of clear lexan polycarbonate for a see-through look. Yet other artificial rock climbing structures make use of specialized graphic designs to attract children and provide a means for subsidized advertising dollars. Hence, advancements to artificial climbing structures for use in a fixed location such as a climbing gym, climbing store and the like, have gradually enhanced these practice climbing facilities by providing realistic walls that closely approximate natural rock formations. In addition, advancements to artificial climbing structures in a water environment have enhanced water-parks, swimming pools, and lakes by providing a new water-sport device to swimmers.
[0007] As climbing has further increased in popularity, attempts have been made to provide portable climbing structures that can be set up for temporary use at fairs or other events. Also, many colleges, universities and resorts have built elaborate artificial rock climbing facilities.
[0008] Water based rock climbing walls, on the other hand, allow swimmers to enjoy rock climbing in a pool or lake environment where the water cushions your fall. Swimming ranks number one in sports participation rankings with over 90 million participants annually. Being conservative, water based climbing walls are expected to grow 20-25% per year fueled by today's young adults along with their passion for climbing. Hence, water based artificial rock climbing walls provide an optional activity for indoor and outdoor water-parks, community pools, private pools, resorts, swim clubs, recreation centers, and the like. Over the past several years community pools have been struggling to increase attendance, since teens are drawn to large theme and water parks. Water based rock climbing walls provide community pools with an economical solution to regain that lost attendance.
[0009] Water-based artificial rock climbing walls must be built and designed with numerous environmental concerns in mind, such as, salt water, fresh water, chlorinated water, wind, and the sun's damaging ultraviolet radiation. Obviously, salt water and chlorinated water are corrosive to all metallic components. Therefore, a protective coating may be required for steel, aluminum, and stainless steel. Examples of protective coatings may include, but are not limited to, paint, epoxy coating, powder coating, anodizing, and hard coating depending on the circumstances. Plastics, fiberglass, and other composites have very resilient qualities to the sun, salt, and chlorine.
[0010] Water sports, lake homes, and larger and more expensive water toys, such as trampolines, aluminum rafts, and specialized water ski equipment, have also increased in popularity. This is due in part to the substantial increase in valuations of lake homes and the growing importance of leisure time. In general, owners of lake homes feel wealthier and can justify the feeling of having more disposable income to enjoy their leisure activities.
[0011] A new trend appears to be in the hotel and indoor water-park combination. This trend is growing rapidly and is fueled by leisure travel patterns favoring the drive-to regional hotel resort. Hotels with indoor water-parks achieve a higher occupancy rate and higher revenue per room. Water based climbing walls along with slides, wave-pools, lazy rivers, water buckets, dark tunnels, drops, mat racers, and surf pools are just a few of the attractions offered at indoor water parks.
[0012] All across America there appears to be a growing health concern regarding obesity. It is said that today's parents are expected to outlive their children. Simply, children are lacking exercise. Water based climbing walls provide a new and exciting form of exercise. Children of all ages love to climb.
[0013] In light of the above, it would be desirable to provide improved artificial rock climbing systems and methods. It would be particularly desirable to provide climbing structures that were better suited for use with water sports activities keeping product evolution in mind. Similar to most product life cycles, there will be numerous improvements, betterments, and modifications as time goes on.
SUMMARY OF THE INVENTION
[0014] It is an object of the present invention to provide a water based artificial rock climbing arrangement which may include assist members, i.e., either or both assist shocks and/or power system for easy setup and teardown when mounted to an in-water or near water support surface.
[0015] It is a further object of the present invention to provide a water based artificial rock climbing arrangement which may include a removable water-start panel, and/or an anti-entrapment shield in order to provide climbers with an easier starting point, to minimize entrapment areas of the climbing wall, and to provide additional safety features.
[0016] It is a further object of the present invention to provide a water based artificial rock climbing arrangement which may include a removable anti-climb-over panel to eliminate over-the-top climbing and to provide additional safety features.
[0017] It is a further object of the present invention to provide a water based artificial rock climbing arrangement which may include adjustable and hinged support bars.
[0018] It is a further object of the present invention to provide a water-based artificial rock climbing arrangement with add-on accessories, such as, but not limited to, a removable climbing wall height extension panel, and a simulated water-fall sprinkler system.
[0019] In one aspect of the invention, an artificial rock climbing arrangement includes a generally rigid framework removably attached to a support surface located adjacent a body of water. Further details of representative constructions of an artificial rock climbing arrangement can be found in commonly owned U.S. Pat. No. 6,872,167, to Meissner, filed Mar. 1, 2002, which is incorporated herein by reference.
[0020] A climbing panel structure may be mounted on the framework for defining an artificial climbing surface, the panel structure carrying a plurality of climbing holds. A support structure is secured between the framework and the support surface for mounting the framework and the climbing surface in a substantially vertical orientation when a climber scales the climbing surface. The framework may have a variety of shapes including round, square, or an inverted U-shape, for example, and may include a pair of parallel legs connected together by a bight portion.
[0021] A modification to this invention may include an inner lip or C-channel securely attached to the inside edge of the parallel legs in order to slide in place or otherwise securely fasten the climbing panels. Also, the inverted U-shape may be replaced with just the pair of parallel legs supported by the panel system and sway bar supports.
[0022] In addition, the framework legs may have bottom ends provided with mounting devices removably secured to an end of the support surface. In some embodiments, the mounting devices permit pivotable movement of the framework and the climbing surface relative to the support surface. In another embodiment, the mounting devices prevent pivotable movement of the framework and the climbing surface relative to the support surface. The support surface may take the form of a pier, pontoon boat, pool deck, or other suitable surfaces, such as, luxury yacht, deck boat, floating raft, cruise boat, house boat, etc. The framework and the climbing surface may be movable between a use position and a non-use position. The panel structure may be modular and includes one or more adjacently joined panels removably fastened to the framework. The framework can be made of various materials including, but not limited to steel, aluminum, extruded aluminum, and stainless steel. The framework may be coated with various materials including, but not limited to lacquers, enamels, powder coat, anodizing, hard coating, and epoxy for protection from the elements.
[0023] In an exemplary embodiment, the support structure may include a pair of diagonal support bars, each being connected between one leg of the framework and a connecting plate, square tube, or anchor system attached to the side or the top of the support surface behind the framework. Each connecting plate, square tube, or anchor system may allow for more than one position, one for holding the framework and climbing surface at an angle of generally 90 degrees relative to the support surface, and another for holding the framework and climbing surface at an angle beyond 90 degrees (e.g., between 90 degrees and 135 degrees, or greater) relative to the support surface. The support structure may also provide for linear movement to allow for different amounts of over-hang or under-hang of the complete framework in relation to the support surface edge in order to provide a universal mounting system.
[0024] Each mounting device may be comprised of a mounting plate, a tube, e.g., square or round, or anchor system attached to the edge or the top of the support surface. The mounting plate, square tube, or anchor system may include a pair of spaced apart tubular or flat stock receivers. A triangular or polygonal bracket or plate may be provided on or near the bottom of each framework leg and may have a tubular or flat stock knuckle disposed between the receivers on the mounting plate, square tube, or anchor system. A removable hinge pin may be passed through the aligned receivers and knuckle.
[0025] The diagonal support bars may consist of a hinge system to allow the entire framework to be in a folded down non-use position or a substantially vertical position. The hinge system having a pair of spaced apart flat stock receivers and knuckle securely attached to the diagonal support bar. The hinge pin may be non-removable for safety reasons. The hinge system may also contain a locking mechanism whereby the diagonal support bars would be locked in a fully extended and straight position when the entire framework is in a substantially vertical position. The locking mechanism may consist of a rounded or square shaped rod slideably inserted inside of both halves of the diagonal support bars. The rounded or square shaped rod may completely slide into one-half of the diagonal support bars when unlocked and may slide into both halves of the diagonal support bars when locked.
[0026] The diagonal support bars may consist of lengthwise adjustable ends. One end may be comprised of a threaded male and female component and the other end may be comprised of a male and female telescoping component. The threaded end may be used for small adjustments and the telescoping end may be used for large adjustments. Adjustments are required to align the hinge system, to allow for different climbing angles of the entire framework structure, and to provide a universal product which can be used for more than one type of installation.
[0027] An option includes a pair of assist shocks in combination with or without a pair of actuators in order to provide an automated (motorized) easy-up vertical climbing wall. One end of the assist shocks or actuators may be removably secured to the pair of parallel framework legs and the other end may be removably secured to the mounting plate, square tube, or anchor system, which is mounted on the support surface. The lifting means of the shocks or actuators may comprise of compressed gas, spring, hydraulic, compressed air, low or high voltage electric, or some other power system.
[0028] An additional option includes a removable water-start panel and/or a removable anti-climb-over panel may be installed in order to provide additional safety features. Each of these panels may consist of an independent framework, which will mate or unite with the pair of parallel framework legs. The independent framework of the anti-climb-over panel may be such that when attached to the pair of parallel framework legs, the angle of the panel may be substantially greater than that of the overall framework, thus making it impossible to climb over. In addition, the anti-climb-over panel may have no climbing holds attached to it. The independent framework of the anti-climb-over panel may be attached to the pair of parallel framework legs by telescoping or sliding inside of the framework legs and secured with a retaining pin and/or threaded tension bolt. The independent framework of the water-start panel may be such that when attached to the pair of parallel framework legs, the panel may be partially submerged in water, thus making it easier to begin the climb. Similarly, the independent framework of the water-start panel may be attached to the pair of parallel framework legs by telescoping or sliding inside of the framework legs and secured with a retaining pin and/or threaded tension bolt.
[0029] An additional option may include a sprinkler fitting that may be mounted to the top panel or framework providing for the added thrill of climbing in a simulated waterfall. A pump and hose system (not shown) may be mounted to the framework and support surface.
[0030] The rock climbing arrangement contemplates several different mounting devices, each of which provides for easy set-up and knock down by respective insertion and removal of hinge and retainer pins.
[0031] The entire invention or embodiment may be offered for sale as a kit, which can be installed by someone familiar with water-based rock climbing walls.
[0032] In addition, the entire invention or embodiment may comprise of a modular form whereby more than one embodiment may be placed along side another embodiment by modifying one of the framework legs, whereby two panel mount lips are affixed to each side of a framework leg allowing for panel mounts on both sides.
[0033] An additional option may include alternative shapes (e.g., partial or continuous non-linear) to the climbing wall surface, such as, but not limited to a C-Shape, S-Shape, or Inverted L-Shape. Obviously, there would be limitations placed on the shapes of the climbing wall surface due to safety concerns, manufacturing capabilities, and applied engineering and physics of climbing.
[0034] An additional option may include alternative fixed mounting systems and may include non-fixed mounting systems. The non-fixed mounting systems may include its own counter-weight to hold the wall and the weight of a climber in a generally vertical position. The non-fixed mounting system may eliminate the use of bolts or fasteners being attached to the support surface. The counter-weight may consist of a tank enclosure securely fastened to the base connecting plate, square tube, or other base support system located behind the framework legs. The tank enclosure may then be filled with water, sand, or other flow-based material to provide the necessary counter-weight. The tank enclosure may then be emptied of its contents allowing for easy mobility of the water-based artificial rock climbing arrangement. The tank enclosure may include a fill cap along with a discharge valve, or it may consist of a reversible pump system either mechanical or electrical in order to fill and empty the tank enclosure.
[0035] An additional option may include add-on accessories, such as, but not limited to a removable climbing wall height extension panel, or simulated water-fall sprinkler system. The removable climbing wall height extension panel may allow customers/users with the ability to increase the height of the climbing wall without incurring large costs associated with the purchase of a new climbing wall. Obviously, not all customers/users would be able to take advantage of this accessory due to safety concerns with respect to minimum water depths. A buoy system may also be provided to identify an area for swimmers to stay out of while a climber is attempting to climb the wall. The increased height of the climbing wall would require an increase in the minimum water depth. The height extension panel would be removable in the event that a lower climbing wall is again desired. Sprinkler fittings may be mounted to the top panel or framework providing for the added thrill of climbing in a simulated waterfall. A pump and hose system may be mounted to the framework and climbing wall surface.
[0036] In one embodiment, the artificial rock climbing system is adapted for removable attachment to a support surface adjacent a body of water. The system and methods comprise a generally rigid framework with a climbing surface mounted between the framework, a pair of receivers for hindedly coupling the framework to the support surface, a pair of adjustable support bars coupled between the framework and the receivers, the support bars adapted for positions including a locked, climbing position, and an unlocked, collapsed non-use position, and a pair of assist members for assisted lifting and/or lowering of the framework.
[0037] In an additional embodiment, systems and methods of raising and/or lowering an artificial rock climbing wall system are provided. One embodiment of a method comprises providing an artificial rock climbing wall adapted for removable attachment to a support surface adjacent a body of water, the rock climbing wall including positions between a lowered non-use position and a raised climbing position, and activating an assist member for assisted raising and/or lowering of the rock climbing wall, the assist member positioned between the rock climbing wall and the support surface.
[0038] Various other objects, features and advantages for the invention will be made apparent from the following description taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] The drawings illustrate the best mode presently contemplated of carrying out the invention.
[0040] FIG. 1 is a perspective view of an artificial rock climbing arrangement pivotally attached to the edge of a support surface located adjacent a body of water showing parallel diagonal support bars, assist shocks, and actuators.
[0041] FIG. 2 is a view like FIG. 1 showing the artificial rock climbing arrangement in a collapsed, non-use position.
[0042] FIG. 3 is a close-up view showing the threaded end of the diagonal support bar as seen in FIG. 1 .
[0043] FIG. 4 is a close-up view showing the telescoping end of the diagonal support bar as seen in FIG. 1 .
[0044] FIG. 5 is a close-up view showing the hinged section of the diagonal support bar as seen in FIG. 1 .
[0045] FIG. 6 is a perspective view like FIG. 1 , showing the artificial rock climbing arrangement showing a removable anti-climb-over panel and removable water start panel.
[0046] FIG. 7 is a perspective view like FIG. 1 , showing the artificial rock climbing arrangement showing a panel mount inner lip welded onto the inside edge of the framework legs with sway bar supports and without the U-shape and bight portion.
[0047] FIG. 8 is a perspective view like FIG. 1 , showing the artificial rock climbing arrangement showing an anti-entrapment shield mounted to the lower rear portion of the framework legs and panel system.
[0048] FIG. 9 is a perspective view like FIG. 1 , showing an alternative C-Shape to the framework legs and climbing wall surface, and in addition, a non-fixed counter-weight ballast system attached to the base of the rock climbing arrangement.
[0049] FIG. 10 is a perspective view like FIG. 6 , showing a removable climbing wall height extension panel.
[0050] FIG. 11 is a perspective view of an alternative mounting configuration for the climbing wall to mount to the support structure.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0051] Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structures. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.
[0052] Referring now to the drawings, FIGS. 1 through FIGS. 11 illustrate embodiments of an artificial rock climbing arrangement 10 which may be removably attached to a support surface in the form of a pool deck 12 , for example, located adjacent a body of water 14 . The rock climbing arrangement 10 may be comprised of a generally rigid framework 16 , a modular panel structure 18 mounted on or between the framework 16 , a pair of diagonal support bars 20 between the framework 16 and the pool deck 12 for maintaining the framework 16 and panel structure 18 in a substantially vertical climbing orientation (locked) and an easily collapsed non-use position (unlocked), a pair of assist members, i.e., shocks 22 (gas, spring, hydraulic, air or other) for assisted lifting and/or lowering, a pair of actuators 24 (electric, hydraulic, or other) for motorized or power-up lifting and/or lowering, and a pair of tubular receivers 26 for hindedly coupling the bottom of the framework 16 and triangular plate 28 to the edge of the pool deck 12 . Also, the diagonal support bar 20 , assist shocks 22 , and actuators 24 are adjustably mounted to the tubular receivers 26 using various shaped couplings 27 .
[0053] FIG. 11 depicts an alternative configuration for hingedly coupling a receiver 26 to the framework 16 . As can be seen, bracket 29 may be coupled to the receiver 26 , with a retaining pin 30 hingedly coupling the bracket 29 to the triangular plate 28 and the framework 16 .
[0054] FIG. 2 depicts the rock climbing arrangement 10 pivoted downward to a non-use position along with the diagonal support bars 20 , assist shocks 22 , and actuator 24 in a folded or collapsed non-use position. The non-use position may be defined by the framework 16 and the climbing structure folded rearwardly and downwardly to a horizontal or near horizontal level on top of the pool deck 12 after the diagonal support bars 20 have been unlocked.
[0055] FIGS. 3 , 4 , and 5 depict close-up views of possible elements of the diagonal support bars. FIG. 3 shows one end of the diagonal support bar 20 having a threaded coupling 40 which may be used to allow for small adjustments in the length of the diagonal support bar 20 . Rotational movement of the threaded coupling 40 will lengthen or shorten the overall length of the diagonal support bar 20 . FIG. 4 shows one end of the diagonal support bar 20 having a telescoping coupling 42 which may be used to allow for large adjustments in the length of the diagonal support bar 20 . A retaining pin 44 may be inserted through an aperture 46 located in both the diagonal support bar 20 and telescoping coupling 42 . Lateral movement of the telescoping coupling 42 along with the removal and subsequent insertion of the retaining pin 44 will lengthen or shorten the overall length of the diagonal support bar 20 . FIG. 5 shows a hinge system 48 which allows the diagonal support bar 20 to maintain a rigidly straight or extended position and to allow the diagonal support bar 20 to maintain a collapsed or folded position. In order for the diagonal support bar 20 to maintain a rigidly straight or extended position, pressure may be placed on knob 52 of locking pin 50 and locking pin 50 may be slidably equally received inside both halves of the diagonal support bar 20 . When reverse pressure is placed knob 52 of the locking pin 50 and the locking pin 50 is completed received inside one-half of the diagonal support bar 20 , the centrally located hinge system 48 may be allowed to pivot freely and provide for a folded or collapsed position.
[0056] FIG. 6 depicts a removable water-start panel 60 and a removable anti-climb-over panel 66 . The water-start panel 60 may be mounted to a pair of tubular frames 62 which may be received by the main framework legs 16 of the overall climbing structure. The tubular frames 62 may be locked in place by inserting retaining pin 64 through an aperture in the framework legs 16 and a matching aperture in the tubular frames 62 . The water-start panel 60 and tubular frames 62 may be partially submerged in the water 14 . The water-start panel may be used to provide for an easier and safer climbing position. The anti-climb-over panel 66 may be mounted to a pair of tubular frames 68 which may be received by the main framework legs 16 of the overall climbing structure. The tubular frames 68 may be locked in place by inserting retaining pin 64 through an aperture in the framework legs 16 and a matching aperture in the tubular frames 68 . The anti-climb-over panel may be used to prohibit climbing over the wall. Climbing holds may not be mounted to the anti-climb-over panel. The tubular frames 68 may include an angle of bend approximating 20 degrees, for example, although the angle may be more or less. The tubular frames 68 may include a round collar 70 near the angle of bend in order to provide a slide stop.
[0057] FIG. 7 depicts an alternative modular panel structure 18 mounting system. Whereby, a lip 90 may be welded to the inside edges of the main framework legs 16 . The modular panel structure 18 may be mounted to the lip 90 by drilling holes in the modular panel structure 18 and lip 90 and affixing through bolts and retaining nuts, for example. A sway bar support 92 may be affixed to the rear side of the main framework legs 16 and the rear side of the modular panel structure 18 at the flange in order to prohibit rotational movement of the main framework legs 16 . FIG. 7 also shows the use of a water-fall/sprinkler accessory system 130 .
[0058] FIG. 8 is a partial view of an artificial rock climbing arrangement 10 , which depicts an anti-entrapment shield 100 mounted to the lower rear portion of the framework legs 16 , triangular plate 28 , and the lower flange of modular panel structure 18 . The anti-entrapment shield 100 may or may not rest on the support surface or pool deck 12 .
[0059] FIG. 9 depicts the rock climbing arrangement 10 having an alternative panel structure 18 and an alternative framework 16 forming a C-Shape to the climbing surface. It is to be appreciated that additional non-linear shapes are also possible for the panel structure 18 and framework 16 . Additional framework and climbing surface shapes may include partial non-linear portions, or the framework and climbing surfaces may be a continuous non-linear shape.
[0060] FIG. 9 also depicts the rock climbing arrangement 10 having an alternative ballast counter-weight tank enclosure 110 releasably fastened to the rear portion of the tubular receivers 26 , which may, in combination, rest on the support surface or pool deck 12 with no mounting bolts or fasteners. The tank enclosure 110 shows a fill cap 111 and a discharge valve 112 in order to fill and empty the tank enclosure 110 .
[0061] FIG. 10 depicts a removable height extension panel 120 . The removable height extension panel 120 may be mounted to a pair of tubular frames 121 which are received by the main framework legs 16 of the overall climbing structure. The tubular frames 121 may be locked in place by inserting retaining pin 64 through an aperture in the framework legs 16 and a matching aperture in the tubular frames 121 . The anti-climb over panel 66 along with the tubular frames 68 may then be mounted and received by the tubular frames 121 of the height extension panel 120 . Again, the tubular frames 68 are locked in place by inserting retaining pin 64 through an aperture in the tubular frames 121 and a matching aperture in the tubular frames 68 . The removable height extension panel may be used to increase the overall height of the climbing wall. The tubular frames 121 may include a round collar 70 near the bottom edge of the removable height extension panel 120 in order to provide a slide stop.
[0062] The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact constructions and operations shown and described. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims. | Improved climbing structures, systems, and methods for use on an artificial rock climbing arrangement which includes a generally rigid framework removably attached to a support surface located adjacent a body of water. The framework makes use of assist shocks in combination with actuators in order to provide an automated (motorized) easy-up vertical climbing wall. A panel structure is mounted on the framework for defining a climbing surface, the panel surface carrying a plurality of climbing holds. A hinged adjustable support bar is secured between the framework and the support surface for maintaining the framework and the climbing surface in a substantially vertical orientation when a climber scales the climbing surface. The hinged adjustable support bar is diagonally mounted with telescoping and threaded ends. | 0 |
FIELD OF THE INVENTION
The invention relates to an X-ray diffractometer device, comprising an X-ray source, a collimator device for the source, a sample support, a collimator device for the beam reflected by the sample and a counter producing an output signal in the form of a voltage which is proportional to the number of photons reflected by the sample.
The invention also relates to the use of this glancing device in the slanting incidence mode.
The invention is used in the characterization of multi-layer structures utilized in the X-ray technique, such as, for example, multi-layer mirrors for X-ray optical devices, as well as for measuring the widths of layers of metal, semiconducting or insulating materials having different optical indices.
Thus, the invention allows the measurement of the widths of layers in the nanometer range, the measurement of these widths when two or three nanometer layers of different materials are stacked (two- or three-layer systems), the measurement of the pitch with which the stacking is repeated, the measurement of characteristic parameters of the materials forming these layers, and consequently the identification of these materials, the determination of the surface roughness or the average roughness of the stack.
BACKGROUND OF THE INVENTION
An X-ray diffractometer device is already known from the prior art apparatus, type designation PW1050, marketed by Messrs. PHILIPS (I α E ANALYTICAL ALMELO, the Netherlands).
This device comprises an X-ray source, a system of collimation slits for the beam coming from the source, a sample support, arranged such that the incident beam reaches the sample at an angle of incidence equal to (π/2)-θ, or, put differently: at an angle θ to the plane of the sample-support, a collimation slit system of the reflected beam, and a detector for detecting the number of reflected photons, of the proportional counter type.
Proportional counter must here be understood to mean a device containing gas which can be ionized by the flux of photons to be detected and supplies a signal in the form of a voltage which is proportional to the number of photons. Actually, the response of the proportional counter is only linear in a certain range of intensities. When the intensities reflected by the sample are too weak or too strong, one lands outside the linearity region of the counter.
Now, the diffractometry device already commercially available is not suitable for the intended use to characterize multi-layer samples, and also not for measuring layer widths, because of the fact that it can only operate in a certain range of angles of incidence. Thus, this apparatus is perfectly suitable for measuring mesh parameters of samples of powders of different materials, since in the case of powders, the angles of incidence do not have very high values, that is to say they are generally not located in the range of glancing angles or orthogonal incidences. The measurement of the mesh parameters is obtained by interpreting variations in the output signal of the proportional counter. These variations form peaks having an amplitude which is proportional to the number of photons received by the detector and whose distance is also characteristic of the material, more specifically of its mesh parameters. Comparing these measurements to the data contained in Classifying Tables renders it possible to determine the mesh parameters of the powder under investigation and to derive therefrom the nature of the composite material.
Measuring the mesh parameters by means of this method, using the known apparatus with the type designation mentioned in the foregoing, is founded on the Bragg relation:
2d. Sin θ=λ,
wherein λ= the wavelength of the source, constant value,
θ= the angle between the path of the incident beam and a reticular plane of the investiagted material,
d= the mesh parameter of the material forming the investigated powder, for example.
As the prior art apparatus is arranged for investigating powders, in conditions far removed from glancing incidence, the measurements performed with this apparatus can only be applied to materials having a mesh parameter d of a low value.
Now, at present it is necessary that one can characterize not only powders, but also bulky elements, for example multi-layer mirrors operating in the field of soft X rays, or thin metal, semiconducting or insulating layers, all solid materials.
For example, the said bulky element or multilayer mirror is formed by an alternation of at least two materials having different indices of refraction: a what is called heavy material and a what is called light material. The spacing between the layers is imposed by the structure of the mirror.
Characterizing this type of bulky element requires the measurement of large parameters d. Consequently, from the relation stated hereinbefore, the result is that, the wavelength of the source being fixed, only the measurement at very small angles of incidence θ (glancing incidence) renders it possible to obtain the characterization of materials having large parameters d, or, when layer thicknesses are measured, allows measuring of widths comprised between 1 and 300 nm.
It is not possible with the known apparatus, whose type designation has been mentioned hereinbefore, to operate in the case of very glancing incidence because of limitations of the proportional counter. In fact, with glancing incidence, the reflected intensities are very strong, and because of a saturation phenomenon, the proportional counter is outside the range of intensities in which its response is linear. Consequently, it is not possible to obtain the characterization of the intended samples, mentioned in the foregoing, using the known apparatus.
On the other hand, for solid samples such as the said multi-layer mirrors, it must be necessary that the angle of incidence (π/2)-θ of the values wherein θ=0 to the values wherein θ is still low but not zero, for example θ=2° or θ=4° . During this variation, the reflected intensity varies in large proportions. If, for example, the reflected intensity is within the linearity range of the proportional counter for θ=0°, it is no longer in this range, by lack of intensity for θ=2°. Conversely, if the intensity is within the linearity range of the proportional counter for θ=2°, it is no longer in this range for θ=0° because of the excessive increase of the reflected intensity.
A solution known to a person skilled in the art of optics of the problem created by an excessively high luminous intensity in a system, is to interpose an absorbing filter.
But, as has been stated in the foregoing, this solution is not directly applicable to the prior art apparatus, because of the fact that if the reflected intensity is within the linearity range of the counter in one of the measuring conditions, it is no longer in this range from the instant at which the conditions for the same measurement have changed.
A solution must therefore be found for the problem of interposing a given filter as a function of the photonic intensity reflected from a given sample when the measuring conditions vary during one measurement.
The solution then found renders it possible to realise measurements not only of solid samples but also of samples with large mesh parameters, as well as of samples which are simultaneously solid and have large parameters, that is to say when the parameters of the sample vary from one measurement to the other.
SUMMARY OF THE INVENTION
According to the invention, this problem is solved using a device having characteristics as defined in the opening paragraph and furthermore having characteristics defined in the characterizing part of the claim 1.
Such a device has the advantage that, as soon as the reflected intensity approaches a value from which the proportional counter does not operate linearly anymore, the absorbing filter, when active, is automatically replaced by a different filter whose absorption is such that the proportional counter again operates linearly.
Thus, on the one hand the proportional counter always operates in the range in which it is linear, and on the other hand all the measurements can be effected continuously, whatever the angle and/or type of sample, without the need for action on the part of the operator.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention and its advantages will be better understood from the following description given with reference to the accompanying Figures:
FIG. 1 is a schematic view of a standard diffractometer device, additionally provided with a measurement automation system in accordance with the invention;
FIG. 2a is a schematic view of the mechanical portion of this automation system in a plan view;
FIG. 2b is a schematic view of the mechanical portion of this system taken on the line III--III of FIG. 2a;
FIG. 3 illustrates, by means of a block diagram, the processing procedure of the measuring signal in the automation system;
FIG. 4a shows an example of a measurement obtained with the aid of the diffractometry device provided with the automation system, before digital processing;
FIG. 4b shows the same example of a measurement after digital processing.
As is shown in FIG. 1, an X-ray diffractometer apparatus includes at least the elements known from the commercially available Philips apparatus PW1050, i.e.
a linear X-ray source 1 ; actually, the X-ray sources available on the market have a linear source this source is furthermore positioned such with respect to the optical axis of the device that it encloses with this axis a smaller or a wider angle, denoted sampling angle ; the useable luminous intensity may depend on the sample angle;
a collimator system 2 and 3 including the Soller slits 2 and a divergence slit 3;
a goniometric sample support 11 comprising sample orientation means 10, not shown; these orientation means comprise more specifically the control of the angle of incidence; for the sake of simplicity, the expression "incidence θ" will be used to designate the angle θ between the beam and the sample plane when the angle of incidence is (π/2)-θ;
a collimator system 5 formed by a so-called receiving slit;
a monochromator 7 of the graphite monochromator type, in the field of XR (X-rays);
a proportional counter 8.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In accordance with the invention, the prior art apparatus is modified to render the measurement of large parameters d possible, the value d of predetermined parameters being linked to θ and λ, the wavelength of the source by the relation
2d Sin θ=λ, the so-called Bragg relation.
On the one hand, to obtain the measurement of ever larger parameters d, the choice of the source is influenced, that is to say the choice of λ. To this effect the X-ray source is chosen from among one of the sources specified in Table I which shows the wavelengths λ in Å=(1/10)nm as a function of the rays Kα of several X-ray metal sources.
On the other hand, one opts for having the angle θ vary in the range in which the incidence is a glancing incidence, i.e. for
0°≦θ2° of angle
This modified apparatus is used in the determination of the mesh parameters of solid materials, the width of mulyi-layer materials such as interferential mirrors for X rays, surface roughness values or average stack roughness values.
When the apparatus operates in the glancing incidence mode, the intensity reflected by a solid sample 10, located on the sample support 11, is much greater than when the sample is a powder.
For a flat sample, the reflection of the beam is total, i.e. the reflectivity is equal to 1, up to an angle θ c which more specifically depends on the wavelength λ, the density and the nature of the material.
The result is that the proportional counter 8 receives a quantity of photons which is greater than provided by the designer and the counter then is in a non-linear operating range.
To resolve this problem, in accordance with the invention, there is inserted in the path of the beam reflected by the sample, between the receiving slit 5 and the graphite monochromator 7, an appropriate filter 62, for absorbing a portion of the reflected intensity in such a manner that the intensity of the baem propagating towards the porportional counter 8 corresponds to a linear operating range of this counter.
In addition, when in order to perform the measurements, one causes the angle of incidence to vary, for example between 0 and 2°, the reflected intensity varies. As a function of the material, the reflected intensity can decrease in a certain range of variation of the angle θ, evidence peaks for certain values of θ, the amplitude of the peaks and the position of the peaks being characteristics of the material which characteristics allow the determination of the parameters mentioned hereinbefore with reference to the Classifying Tables.
To enable the continual use of the proportional counter 8 in a linear operating range whatever the angle of incidence θ and consequently the value of the reflected intensity, means 6 are provided in accordance with the invention with the object of inserting a plurality of filters 62, for example 62a, 62b etc. between the receiving slit 5 and the graphite monochromator 7. The absorption of these filters is chosen as a function of the reflected intensity to provide that the proportional counter 8 always operates in a linear operating range.
The Table I shows as a function of the X-ray sources and their associated wavelength λ (in Å), examples of filters made of different metals (Ni, Al, Cu) having widths e in μm to obtain the absorption coefficients A=I 0 /I, I 0 being the incident intensity, and I the intensity after absorption by the filter.
In the Table I the filter widths e are given, as well as the metals from which the filters are made, in such a manner that absorption coefficients A are obtained which are as close to the value 10 as possible; examples of filters are also given (width e, and metal material) to obtain an absorption A as close as possible to 5. Other values of the absorption A may be chosen by a person skilled in the art by interpolating values on the basis of Table I. For example, absorption coefficients A are obtained having the respective values 10 0 , 10 1 , . . . 10 n (wherein n is an integer) by multiplying the widths e from e=0 (corresponding to A=1) up to nxe when e corresponds to an ansorption coefficient of approximately 10.
In accordance with the invention, an automation system is thereafter provided for positioning the appropriate filter 62 to ensure that the proportional counter continually operates in a linear operating range whatever the angle of incidence θ.
The automation system 20 includes mechanical means 6 to support the filters and to position them and data processing means for controlling the filter supports.
In accordance with the invention, there is further provided a system 30, 40, 50 for processing the signal Y coming from the proportional counter as a function of the information X formed by the incidence θ, to obtain a curve Y as a function of continuous X by associating the curve section obtained in the various intensity regions covered during a measurement, and to obtain a systematic comparason to theoretical curves so as to automatically effect the determination of the envisaged parameters.
FIG. 1 shows, in addition to the automation device 20, the display screen 30 on which the curves of the intensities I appear as a function of the angle θ; the data processing computer is denoted by reference numeral 40; and the block 50 represents the theoretical curves obtained on the computer.
FIG. 2a is a front view, i.e. a view perpendicularly to the plane of FIG. 1, of mechanical means 6 for supporting the filters and putting them in position.
TABLE I______________________________________Source λ(source)Å Metal(filter) e(filter)μm A______________________________________Mo Kα 0.709 Ni 50 8.2Cu Kα 1.542 Ni 50 9Ni Kα 1.659 Ni 50 14.3Ni Kα 1.659 Al 100 5.4Ni Kα 1.659 Al 140 10.0Co Kα 1.790 Al 100 8.11Fe Kα 1.937 Al 60 5Fe Kα 1.937 Al 90 10.8Cr Kα 2.290 Al 60 12.93Cr Kα 2.290 A 45 6.8ρ(Ni) = 8,90ρ(Al) = 2,70______________________________________
TABLE II______________________________________ Metal NoSource λ(source)Å (filter) (filter) e(filter)μm A______________________________________Ni Kα 1.659 Al 62 e 140 10 62 d 2 × 140 .sup. 10.sup.2 62 c 3 × 140 .sup. 10.sup.3 62 b 4 × 140 .sup. 10.sup.4 62 a 5 × 140 .sup. 10.sup.5 62 f 0 1______________________________________
These mechanical means 6 comprise a filter support 60 having N windows, to accomodate N filters. When N=6 as is shown in FIG. 2a, the filters have reference numerals 62a, 62b, 62c, 62f and 62e. They are arranged such that, when one passes in a continuous manner from one filter to the other, they have an absorption with decreases by a constant factor.
In the specific case represented by way of example in FIG. 2a, a filter support 60 in the shape of a round plate is chosen which can rotate around its axis 61. The filters are accomodated in equally spaced peripheral apertures. The value of the absorption coefficients A of the filters is chosen such that it decreases by a factor closest possible to 10 when one passes from one filter to the other.
Thus, using Table I, it is possible to realise the automation device shown in FIG. 2a, while chosing, for example, the different filters of the Table II, for, for example, a NiK α source.
In order to bring a given filter 62 into the path of an X-ray beam reflected by the sample 10, the plate 60 rotates around its axis 61 under the action of a transmission belt 64 connected to a second plate 68. This plate 68 is driven, for example via its shaft 69, or via any other means, simultaneously with the plate 60, by a first motor, denoted "filter motor". The second plate 68 includes apertures 66a to 66e equal to the number of filters 62a to 62f, uniformly distributed around its circumference.
FIG. 2b is a sectional view along the axis III--III of FIG. 2a. So as to position a given filter in the path of the beam reflected by the sample 10, two emitter-receiver diodes 71a, 71b are arranged on either side of the plate 68, at a distance from the axis 69 equal to the distance of the apertures 66. The apertures 66 are posioned such that when a filter is in the chosen position, an aperture 66 is simultaneously located in the axis of the emitter-receiver diodes 71a-71b, so that the signal from the receiver diode controls stopping of the "filter motor" driving the plates 60 and 68.
The "filter motor" which simultaneously drives the positioning control plate 68 and the filter support plate 60 is moreover controlled by data processing means. The object to be achieved by the device in accordance with the invention is to obtain the continuous recording of the signal supplied by the proportional counter as a function of the incidence θ=X.
The functions put into effect by the control processing means are shown in FIG. 3.
These functions include encoding, by means of an encoder 27, of a signal corresponding to the filter located in the path of the reflected beam. This encoded information is then transferred as data to a microprocessor card in combination with a main computer 25.
The function of starting (start-stop) the first motor, called "filter motor", is denoted 26. On the other hand, the signal Y provided by the proportional counter 8 is recorded in mV as a function of θ, (signal X). As soon as the signal X gets either less than a predetermined value, or higher than an other predetermined value, the stop order for a second motor, called "sample motor", which causes the sample to proceed by one step Δθ when there is incidence θ+Δθ, is given to the microprocessor card 24, via an encoder 21. The order to stop reaches the "sample motor" 28 via the start-stop function 22, via the encoder 21.
The "filter motor" 26 then starts operating to allow, via the system 6, the positioning of either a more absorbing or less absorbing filter. This operation is effected by the control 26 of the "filter motor" which reaches the system via the encoder 27.
Once the rotation of the filter support 60 has been realised, the "filter motor" is stopped (by the diode system 71a-71b) and the command to restart the recording is given by the start-stop control 22 of the "sample motor" via the encoder 21. On the other hand, the function 23 is a function to reverse the "sample motor" when the said motor arrives at the end of run 0 or θ in one direction or the other.
When the least absorbing filter is in position (for example the filter 62f, having absorption 1), recording of the data Y coming from the counter and X coming from the sample motor might continue without cessation, even if the measured value becomes low at a predetermined low limit value.
The encoder 21 located on the sample motor allows in essence the choice of the measuring steps Δθ0.
In these, using the device in accordance with the invention, an extension of the counting rate of the proportional counter is obtained.
FIG. 4a shows an irregular curve obtained by means of the device in accordance with the invention. In the portion A of the curve, the reflected intensity, plotted at Y, is first very great. Therefore a highly absorbing filter is used. Thereafter the intensity decreases as a function of the angle θ plotted at the X axis. In the bottom region of the portion A, this intensity will be difficult to define if the recording is not cut off at point A 2 . The highly absorbing filter is then replaced by a filter which is approximately 10 times less absorbing, by rotating the filter support 60, the recording is thereafter restarted. Then the portion B 1 -B 2 is obtained. At B 2 , the intensity becomes still weaker and recording is again stopped. The filter is replaced by a filter approximately 10 times less absorbing, by rotating the filter support 60, the recording is thereafter restarted.
If in contrast thereto, the intensity increases to beyond a predetermined value, the recording is again stopped and a filter having a higher absorption is brought into position.
Thus, positioning of the filter appropriate to the predetermined intensity range is effected automatically. There is no need for the operator to interfere in this operation during the course of recording of the signal Y of the counter as a function of X=θ.
To obtain furthermore a smooth recording curve, second data processing means are accomodated. FIG. 4b shows the curve of FIG. 4a when the data have been processed. The curve is then a continuous curve, the terminals A 2 and B 1 , B 2 and C 1 etc. having been brought to coincidence.
These second data processing means comprise a logic circuit but may optionally be constituted by a wired circuit. When a logic circuit is sued, the following algorith is employed:
______________________________________1) Initialising the measurement of the signal supplied by theproportional counter, i.e. a mV multimeter having a range from 0to 100 mV.2) MEASURING a) Boundary of the graph b) Boundary of the measurement c) Filter change test d.sub.1) If the multimeter measures >90 mV →, the most absorbing filter is placed in position ; d.sub.2) If the multimeter measurement < bounds of the minimal reflection (for example, 20 or 50 mV)→, the least absorbing filter is positioned;3) End of measuremnt a) SAVING the file b) NORMALISING and correcting the measurements. c) STORING a measurement → name of the file4) RETRIEVING the a.sub.1) linearmeasurements a.sub.2) linear-logarithmical.5) PRINTING: printed output6) FORMATTING (ASCII) = Converting a file intomachine language for use by the main computer.______________________________________ | The invention relates to an X-ray diffractometer device, comprising an X-ray source, a collimator device for the source, a sample support, a collimator device for the beam reflected by the sample and a counter producing an output signal in the form of a voltage which is proportional to the number of photons reflected by the sample. This device furthermore includes a motor drive for the sample support, recording means for the signal Y originating from the proportional counter as a function of the angle θ between the plane of incidence of the sample and the incident beam, denoted X, mechanical means having a support for a plurality of filters having different coefficients of absorption and including a motor drive for this filter support, data processing means for selecting one of the filters of the filter support and for controlling the motor drive of the sample support, the motor drive of the filter support and the recording means, respectively. | 6 |
BACKGROUND OF THE INVENTION
The present invention generally relates to the field of aircraft navigation, and particularly to a split PPS/SPS architecture for military aircraft flying in civilian airspace.
Emerging Global Air Traffic Management (GATM) and Joint Precision Approach and Landing System (JPALS) requirements continue to drive military aircraft toward a need for civil interoperability when engaged in flight in the national airspace. However, this interoperability cannot compromise the performance of military aircraft systems when in a tactical environment. Military aircraft are increasingly being required to show “civil interoperability” up to, and including Federal Aviation Administration (FAA)/civil aviation authority (CAA) certification of onboard equipment, including GPS equipment.
The tremendous growth in air traffic presents increasing challenges for air traffic service providers, air carriers, and the military. Such growth is straining airspace capacity and airport resources. The air traffic system requires significant upgrades to increase system capacity and flight efficiency while continuing to meet flight safety standards. The International Civil Aviation Organization (ICAO), Federal Aviation Administration (FAA), and other civil aviation authorities (CAA) plan to implement a new air traffic architecture to meet this need. This new architecture takes advantage of emerging technologies in communication, navigation, and surveillance to improve air traffic management.
The current plan is to implement a new air traffic environment to culminate in 2010 with the attainment of dynamic routing, commonly referred to in the U.S. as “free flight.” Dynamic routing gives operators the freedom to choose their own routes, speeds, and altitudes, in real-time, thus providing visual flight rules (VFR) flexibility with instrument flight rules (IFR) protection and separation and a shift from air traffic control (ATC) to air traffic management (ATM). The civil aviation community refers to these changes as Communication, Navigation, Surveillance/Air Traffic Management (CNS/ATM). Due to the major impact to Department of Defense global operations, these new concepts will be referred to as Global Air Traffic Management (GATM).
The ability to reduce aircraft separations and implement other new air traffic management (ATM) procedures while maintaining or improving safety standards is based on the use of new technology. The most critical technology elements of the new Communication, Navigation, Surveillance/Air Traffic Management (CNS/ATM) environment are satellite-based navigation, increased use of data links rather than voice for pilot/controller communication in oceanic/remote airspace as well as en-route and terminal environments, and improved surveillance that will enhance both ground and cockpit situational awareness. If aircraft are not equipped with the appropriate new technologies, they will not be able to operate in airspace where new separation standards and ATM procedures are implemented by civil aviation authorities, and will therefore be excluded from that airspace. For Department of Defense aircraft to operate in this new environment, significant modifications to existing aircraft must be accomplished.
One element of the GATM problem is Satellite based navigation or GPS. Implementation of GPS in all military aircraft is now mandated by 2005. To meet this mandate, military aircraft system program offices (SPOs) integrated P(Y) code GPS in three basic configurations: stand-alone receiver 3 A, Miniature Airborne GPS Receiver (MAGR), cargo utility GPS receiver (CUGR), integrated with a flight management system (FMS) CDNU GPS Embedded Module (CGEM), or embedded/integrated with an inertial (GPS Embedded Module (GEM)), or GRAM.
Historically, the military and the civilian market follow different paths to certify their systems for flight. The FAA/CAA drives a process intensive, regimented development process to ensure a receiver meets the technical standard order (TSO) for flight critical systems. The military also follows a regimented development process; however, to date most military systems are not required to meet the FAA/CAA guidelines. Instead, the military self-certifies their systems as meeting the needs for flight in civil airspace.
To meet the emerging GATM requirements, the military market encourages the use of commercially available aviation equipment. However, military and civil markets have diverging requirements. For the civilian market, Local Area Augmentation System (LAAS), Wide-Area Augmentation System (WAAS) and the new civil frequency are the near term driving requirements. In the military market, Wide-Area Augmentation System (WAAS), Joint Precision Approach and Landing System (JPALS), the new military M-Code Signal (Lm), selective availability anti-spoofing module (SAASM) and navigation warfare (NAVWAR) anti-jamming (AJ) enhancements are driving requirements. This divergence in driving requirements is causing a debate over the best way to pre-position aircraft for flight in civil airspace and address the concerns to meet the divergent civil and military needs.
The first part of the controversy is the use of precise encrypted P(Y) code GPS in civil airspace. P(Y) GPS is designed to meet the rigorous needs of the tactical military environment. Unfortunately, the drive for military use complicates and diverges from the goals of a civil certified GPS receiver. PPS receivers utilize L 1 and L 2 to calculate the GPS position and perform ionosphere corrections. L 1 is a protected frequency for safety of flight operations, but L 2 is not. Therefore, in order for the PPS receiver to operate in the civil airspace, the receiver must be capable of excluding L 2 from the solution.
A second issue is the certification of PPS receivers by foreign CAA. The current generation of PPS receiver has classified software that is not accessible for inspection by foreign governments (the exception is Category A & B memorandum of understanding (MOU) countries). Since every foreign government retains the right to approve aviation equipment for flight in their sovereign airspace, they need to be able to inspect the software operating within the GPS receiver. To utilize a PPS receiver, the military would require a country-by-country waiver or agreement to allow the use of a PPS receiver within their airspace. This is further complicated with the incorporation of Selective Availability Anti-Spoofing Module (SAASM) since no foreign government has access to the classified algorithms within the Selective Availability Anti-Spoofing Module (SAASM).
Finally, a technical standard order (TSO) does not exist for a PPS receiver. While a manufacturer may claim some level of TSO or TSO equivalency, the fact remains that a TSO has not been written for PPS receivers and therefore the PPS portion of a receiver can not be TSO'd. In addition, it is unlikely that a TSO will be developed in the near future because of the issues presented previously.
Therefore, it would be desirable to provide a navigation system that is suitable for certification by civil aviation authorities (CAA) yet still provide the tactical environment capability (high anti-jam, anti-spoof) required for military needs.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a split PPS/SPS architecture for military aircraft flying in civilian airspace. To satisfy disparate Civil and Military aviation requirements, separate GPS receivers will satisfy the operational need of the Military User and the certification requirements of the Civil Aviation Authorities (CAA) at a lower life cycle cost than an approach to meet both requirements in a single receiver.
In a first aspect of the present invention, a navigation system suitable for use in civilian airspace, includes a first precise positioning service (PPS) global positioning system (GPS) receiver in a first line replaceable unit (LRU). A second standard positioning service (SPS) global positioning system (GPS) receiver in a second line replaceable unit (LRU) is also included. The second standard positioning service (SPS) global positioning system (GPS) receiver in the second line replaceable unit (LRU) is suitable for at least one of certification, upgrade and replacement independent of the first precise positioning service (PPS) global positioning system (GPS) receiver in the first line replaceable unit (LRU).
In a second aspect of the present invention, a vehicle including a navigation system includes a first precise positioning service (PPS) global positioning system (GPS) receiver in a first line replaceable unit (LRU). A second standard positioning service (SPS) global positioning system (GPS) receiver in a second line replaceable unit (LRU) is also included. The second standard positioning service (SPS) global positioning system (GPS) receiver in the second line replaceable unit (LRU) is suitable for at least one of certification, upgrade and replacement independent of the first precise positioning service (PPS) global positioning system (GPS) receiver in the first line replaceable unit (LRU).
In a third aspect of the present invention, a navigation system suitable for use in civilian airspace, includes a first precise positioning service (PPS) global positioning system (GPS) receiver in a first line replaceable unit (LRU). A second standard positioning service (SPS) global positioning system (GPS) receiver in a second line replaceable unit (LRU) is also included. The second standard positioning service (SPS) global positioning system (GPS) receiver in the second line replaceable unit (LRU) is certified under a technical standard order corresponding to operation utilizing a standard positioning service and is suitable for at least one of certification, upgrade and replacement independent of the first precise positioning service (PPS) global positioning system (GPS) receiver in the first line replaceable unit (LRU).
In a fourth aspect of the present invention, a navigation system suitable for use in civilian airspace includes a line replaceable unit (LRU). A first precise positioning service (PPS) global positioning system (GPS) receiver and a second standard positioning service (SPS) global positioning system (GPS) receiver are included with the line replaceable unit (LRU). The second standard positioning service (SPS) global positioning system (GPS) receiver is suitable for at least one of certification, upgrade and replacement independent of the first precise positioning service (PPS) global positioning system (GPS).
It is to be understood that both the forgoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention and together with the general description, serve to explain the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The numerous advantages of the present invention may be better understood by those skilled in the art by reference to the accompanying figures in which:
FIG. 1 is a table depicting exemplary options for compliance with flight requirements in civilian airspace;
FIG. 2 is a block diagram depicting exemplary options as shown in FIG. 1 wherein navigational systems include various combinations of certified and non-certified global navigation system components;
FIG. 3 is a chart illustrating exemplary evaluation criteria including cost aspects of the exemplary options shown in FIGS. 1 and 2;
FIG. 4 is a chart illustrating exemplary evaluation including upgrade costs of the exemplary options shown in FIGS. 1 and 2;
FIG. 5 is a chart is shown illustrating exemplary evaluation criteria including risks and issues of the exemplary options shown in FIGS. 1 and 2;
FIG. 6 is a chart depicting a summary of the exemplary criteria as discussed in relation to FIGS. 3, 4 and 5 for evaluating compliance options; and
FIG. 7 is a block diagram depicting exemplary embodiments of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings.
Referring generally now to FIGS. 1 through 7, exemplary embodiments of the present invention are disclosed.
There are a number of choices to satisfy future airspace requirements: combined SPS & PPS receiver—not certified; combined SPS & PPS receiver—certified; separate SPS (TSO'd) & PPS (non-TSO'd) receivers in one line replaceable unit (LRU); or separate SPS (TSO'd) & PPS (non-TSO'd) receivers in separate line replaceable units, examples of which are shown in FIG. 1 . The first option is a combined SPS and PPS receiver that is not SPS TSO'd, not PPS TSO'd, and not LRU certified. The second option is a combined SPS and PPS receiver, wherein the SPS receiver is TSO'd, the PPS is not TSO'd, and it is line replaceable unit (LRU) certified. The third option is a separate SPS & PPS receiver in one line replaceable unit (LRU), where it is SPS TSO'd, is not PPS TSO'd and is line replaceable unit (LRU) certified. The fourth option is a separate SPS & PPS receiver in separate line replaceable units, wherein the SPS is TSO'd, the PPS is not TSO'd, and the SPS is line replaceable unit certified and the PPS is not line replaceable unit certified. Certification of the LRU will include testing to meet the applicable RTCA requirements levied on that LRU. It should be appreciated that there are numerous other possible permutations of the options shown in FIG. 1 . However, these options are shown for the sake of clarity of the discussion as representative of the most likely set of options to be analyzed given the current military GPS integration and the emerging GATM requirements for civil compatibility.
Referring now to FIG. 2, an illustration of the exemplary options of the present invention as described in relation to FIG. 1 is shown. The first option 202 includes a non-certified navigation line replaceable unit 204 which includes a combined non-TSO'd SPS and PPS GPS receiver 206 . The second option 208 includes a certified navigation line replaceable unit 210 with a combined TSO'd SPS/Non-TSO'd PPS GPS receiver 212 . The third option 214 includes a certified navigation line replaceable unit 216 including a TSO'd SPS GPS Receiver 218 and a Non-TSO'd PPS GPS Receiver 220 . The third option 214 includes the TSO'd SPS GPS Receiver 218 and the Non-TSO'd PPS GPS Receiver 220 in a single certified line replaceable unit 216 . The fourth option 222 includes a first non-certified navigation line replaceable unit 224 including a non-TSO'd PPS GPS Receiver 226 and a second certified Navigation line replaceable unit 228 including a TSO'd SPS GPS receiver 230 . Thus, the fourth option provides separate line replaceable units 224 and 228 to enable the replacement and testing of the PPS GPS receiver 226 and the SPS GPS receiver 230 separately.
Referring generally now to FIGS. 3 through 5, exemplary criteria are shown that may be utilized for analysis of the desirability of the exemplary options shown in FIGS. 1 and 2. To structure this analysis, the four exemplary options will be evaluated based on development costs, integration costs, certification costs, upgrade costs, hardware costs and total life cycle cost. In addition, the operational impact to the existing platforms will be identified, such as aircraft certification issues and future upgrade issues.
Referring now to FIG. 3 a chart is shown illustrating exemplary evaluation criteria including cost aspects of the exemplary options shown in FIGS. 1 and 2. The first option includes a non-certified navigation line replaceable unit including a combined non-TSO'd SPS and PPS GPS receiver. The development costs of both the system and receiver, as well as the initial system integration costs would be low, but the aircraft certification costs would be very high. This is due to the fact that neither the PPS nor the SPS receiver is TSO'd, an essential system of the aircraft, thus making it especially difficult to certify the aircraft. The second option includes a certified navigation line replaceable unit with a combined TSO'd SPS/Non-TSO'd PPS GPS receiver. The system development costs would be low, but the receiver development costs would be high. This is because both the PPS and the SPS receiver must be developed and maintained to stringent RTCA/DO-178B software development standards. The initial system integration costs for the coarse acquisition GPS receiver would be low since the MMR already drives the instruments, but the integration costs for the P(Y) GPS receiver would be medium because of the necessity of rewiring to unique PPS interfaces. Further, the effect on aircraft certification costs would be low because the LRU is already certified.
The third option includes a TSO'd SPS GPS Receiver and the Non-TSO'd PPS GPS Receiver in a single certified line replaceable unit. The system development costs would be of a medium cost factor as the system would have to be designed to accept the single line replaceable unit. However, the receiver development costs would be low since the receivers themselves would not be combined. The initial system integration costs for the coarse acquisition GPS receiver would be low since the MMR already drives the instruments, but the integration costs for the P(Y) GPS receiver would be medium because of the necessity of rewiring to unique PPS interfaces. Additionally, the aircraft certification costs would be low since the line replaceable unit is certified.
The fourth option includes a first non-certified navigation line replaceable unit including a non-TSO'd PPS GPS Receiver and a second certified Navigation line replaceable unit including a TSO'd SPS GPS receiver. The development costs of the fourth option would be of a medium level due to the requirement of integrating the separate unit in the system. However, the initial system integration costs would be low. Further, the receiver development costs would be low since extensive modifications to the receiver would not be necessary and the aircraft certification costs would be low due to the use of a certified line replaceable unit with a certified SPS receiver. Therefore, in the fourth option, the SPS receiver in the line replaceable unit may be TSO'd and upgraded separately from the PPS receiver, providing greater flexibility and increased cost savings.
Referring now to FIG. 4, a chart is shown illustrating exemplary evaluation criteria including upgrade costs of the exemplary options shown in FIGS. 1 and 2. The first option, a non-TSO'd combined SPS & PPS receiver, would have low upgrade costs. For example, upgrading a selective availability anti-spoofing module (SAASM), Wide-Area Active Surveillance (WAAS), Joint Precision Approach and Landing System (JPALS), and the like would barely be affected because this option is not certified. However, the second option, a TSO'd navigation line replaceable unit with a combined TSO'd SPS/Non-TSO'd PPS GPS receiver, would have very high upgrade costs because the entire unit would have to be recertified. The third option, a TSO'd SPS GPS Receiver and the Non-TSO'd PPS GPS Receiver in a single line replaceable unit, would have a medium upgrade cost, but would have lower upgrade costs than option two. This is because the receiver is in one integrated unit, thus requiring a higher certification cost but it may be removed and certified separately from the system. The fourth option, a first non-TSO'd navigation line replaceable unit including a non-TSO'd PPS GPS receiver and a second TSO'd Navigation line replaceable unit including a TSO'd SPS GPS receiver would have low upgrade costs. This is because the by providing a SPS receiver and PPS receiver in separate line replaceable units, upgrades made to either receiver may be done as needed without unnecessary changes to the non-upgraded portion. However, the equipment size of option four is greater than for options one, two or three due to the provision of separate line replaceable units (LRUs).
The equipment costs of option one and option two are lower than for options three and four due to the configuration as a line replaceable unit. However, the life cycle costs for options one and four are lower than for options two and three. In the case of option four, the life-cycle cost is lower due to the ability to replace either the SPS receiver or PPS receiver as needed, whereas the totality of the SPS and PPS receiver must be replaced in options two and three if defective or in need of upgrade. Thus, even though option four may have a higher initial cost in certain instances, the long-term costs of operation of option four will be lower.
Referring now to FIG. 5, a chart is shown illustrating exemplary evaluation criteria including risks and issues of the exemplary options shown in FIGS. 1 and 2. The operational impact of option one is great, even to the point where civil interoperability is questionable because the unit is not certified. However, the civil interoperability of options two, three, and four is good, due in large part to the certification of the combined SPS & PPS receiver in options two and three as well as the separate SPS receiver in option four. Thus, the certification of the unit is desirable to promote interoperability of the system in a civil airspace.
The impact on the certification of the aircraft varies greatly by option. For example, for option one it is very difficult to certify the aircraft because the GPS receiver is not certified, and there is no recertification of the GPS when changed. For option two, there is questionable aircraft certification because the TSO could be invalidated if the PPS receiver is allowed to drive landing instruments. Additionally, the receiver must be recertified after every modification, regardless of whether the modification is to the SPS receiver or the PPS receiver. Option three makes it fairly easy to certify the aircraft because the line replaceable unit (LRU) is certified. However, there is a need for certification update when the PPS receiver is changed. Since the PPS and SPS receivers are separate modules, it is expected that recertification will be relatively easy and inexpensive. Option four offers easy aircraft certification due to the certification of the separate SPS, and its certification as a line replaceable unit. Thus, like option two, recertification is only necessary when the SPS receiver is changed. However, unlike options two and three, option four offers easy change-ability of the SPS receiver as a line replaceable unit.
Additionally, certification may have an effect on upgrading the unit. For example, in option two, the receiver must be recertified after every modification. Therefore, the costs of the recertification will likely cause a delay in upgrades. Regarding option three, having a non-TSO'd PPS receiver in the line replaceable unit may also delay upgrades, as it is necessary to reintegrate and recertify the line replaceable unit when upgrading. There are no upgrade issues with options one and four. Thus, upgrades may be performed without additional recertification and reintegration costs in these instances.
Referring now to FIG. 6, a chart is shown summarizing the exemplary criteria as discussed in relation to FIGS. 3, 4 and 5 for evaluating compliance options. Option one has a low total cost of ownership due to the uncertified status of the combined SPS and PPS receiver. However, option one also has low certification and operation compliance for the exact same reasons. Thus, option one cannot be considered under the premise that the multi mode receiver (MMR) must be TSO certified. Option two has high certification and operational compliance, however, the cost of ownership is very high due to the price of combining and updating the PPS and SPS receivers. Option two has extremely high recertification costs, since the P(Y) changes will, by definition, impact the FAA safety critical functions. This is because the C/A receiver and P(Y) receiver share common signal processing hardware. Option three is desirable due to the high certification and operation compliance with a medium cost of ownership due to the combination of TSO'd and non-TSO'd receivers in the same line replaceable unit, forcing a reintegration of the line replaceable unit when upgrading. This option does require minor line replaceable unit (LRU) recertification after each PPS upgrade. However, these costs are minimal, provided that the P(Y) GPS receiver changes do not impact the FAA safety critical functions. In addition, this approach does have a size advantage over option four. The cost of replacing the entire line replaceable unit including both the PPS receiver and SPS receiver is the basis of a medium cost of ownership. Option four is desirable, with a lower total cost of ownership due to the ability to replace either the SPS receiver or the PPS receiver as needed, as well as the ability to upgrade separately as well. Additionally, option four has a high level of certification and operation compliance due to the certification of the SPS receiver for civilian flight operations. Thus, commercially available equipment may be utilized with extensive modifications for tactical use. In essence, this approach provides the solution with the lowest life cycle cost (LCC), wile allowing maximum flexibility for future upgrades in both the C/A and P(Y) receivers.
Referring now to FIG. 7, exemplary embodiments of the present invention are shown wherein a split architecture SPS/PPS receiver is shown suitable for utilization in a navigation system. An advantage of option four is its ability to integrate with existing navigation equipment such as the EGI and MAGR, shown in FIG. 7 . The system may include a first non-TSO'd navigation line replaceable unit including a non-TSO'd PPS GPS receiver and a second TSO'd navigation line replaceable unit including a TSO'd SPS GPS receiver. In a first example, a navigation system 702 may include a global navigation and landing unit (GNLU) using a coarse acquisition (C/A) GPS receiver 704 . The navigation system 702 may also include an embedded GPS/Inertial (EGI) navigation unit 706 . Thus, the global navigation and landing unit (GNLU) may be certified separately to enable the aircraft to comply with civilian airspace requirements yet still utilize the precision of the embedded GPS/Inertial (EGI) navigation unit 706 . Additionally, a navigation system 708 may include a multi mode receiver (MMR) with coarse acquisition (C/A) GPS receiver 710 and embedded GPS/Inertial (EGI) navigation unit 712 . Likewise, the multi mode receiver (MMR) with coarse acquisition (C/A) GPS receiver may be certified separately to enable the aircraft to comply with civilian airspace requirements yet still utilize the precision of the embedded GPS/Inertial (EGI) navigation unit 712 . Further, a navigation system 714 may include a multi mode receiver (MMR) with coarse acquisition (C/A) GPS receiver 716 and a miniature airborne GPS receiver (MAGR) 718 . Thus, the split PPS/SPS architecture for military aircraft flying in civilian airspace of the present invention is able to satisfy disparate requirements of the Civil Aviation Authorities (CAA) and Military aviation requirements while remaining cost effective in both production, operation and upgrade expenses. It should be apparent that although exemplary PPS and SPS receivers are discussed, a variety of PPS and SPS receivers are contemplated by the present invention without departing from the spirit and scope thereof.
It is believed that the split PPS/SPS architecture for military aircraft flying in civilian airspace of the present invention and many of its attendant advantages will be understood by the forgoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely an explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes. | In an exemplary embodiment of the present invention, a navigation system suitable for use in civilian airspace includes a first precise positioning service (PPS) global positioning system (GPS) receiver in a first line replaceable unit (LRU). A second standard positioning service (SPS) global positioning system (GPS) receiver in either the same line replaceable unit (LRU) or in a second line replaceable unit (LRU) is also included. The second standard positioning service (SPS) global positioning system (GPS) receiver is suitable for at least one of certification, upgrade and replacement independent of the first precise positioning service (PPS) global positioning system (GPS) receiver. | 6 |
RELATED APPLICATION
[0001] This application is a continuation application of PCT Application No. PCT/CN2013/087929, filed on Nov. 27, 2013, which claims priority to Chinese Patent Application No. 201210499229.5, entitled “METHOD AND SYSTEM FOR IMPLEMENTING REMOTE DEBUGGING”, and filed on Nov. 29, 2012, the entire contents of all of which are incorporated herein by reference
FIELD OF THE TECHNOLOGY
[0002] The present disclosure generally relates to the field of communications technologies and, more particularly, relates to a method and a system for implementing remote debugging.
BACKGROUND OF THE DISCLOSURE
[0003] Remote debugging refers to a debugging policy of using a debugging tool on a computer to debug a program on another computer.
[0004] In an existing remote debugging technology, two parties are mainly included: a debugger and a debuggee. A party that debugs by using a debugging tool is referred to as a “debugger”, for example, a client Visual Studio 2010 that runs a debugging tool; and a party that is debugged by using a debugging tool is referred to as a “debuggee”, for example, a server-side MSVSMON in which a debugging tool is run. By means of the remote debugging, a debugger may enter, from a debugging environment of the debugger itself at the first time, an environment in which a debuggee has a problem, track, and position the root of the problem, thereby improving efficiency of discovering a problem and solving the problem by the debugger, so that the remote debugging becomes very popular among software debuggers.
[0005] In the existing remote debugging technology, a remote debugging and analysis function based on a local area network (LAN) is implemented by using a third-party debugging tool, and at present, common third-party debugging tools include: Visual Studio and WinDbg on a Windows platform, and GNU Debugger (gdb) on a Linux platform. Both the two tools: Visual Studio and the WinDbg are from Microsoft Corporation, while the gdb is a standard debugging device in a GNU system.
[0006] Although all the third-party tools described above provide a remote debugging function, that is, a client of a debugging tool and a server-side program are provided, a connection between a debugger and a debuggee cannot be directly established when the debugger and the debuggee are located in different LANs, because the LANs usually use their own gateways. That is, the remote debugging function of these debugging tools cannot be directly used.
SUMMARY
[0007] Embodiments of the present invention provide a method and a system for implementing remote debugging, which can implement cross-LAN remote debugging. To achieve the foregoing objective, the following technical solutions are used in the embodiments of the present invention.
[0008] One aspect of present disclosure provides a method for implementing remote debugging by a remote debugging system, the remote debugging system including a remote debugging client, a debugger agent, a transit agent, a debuggee agent, and a remote debugging server, the remote debugging client and the debugger agent both belonging to a first LAN, the debuggee agent and the remote debugging server both belonging to a second LAN, the second LAN and the first LAN being different communication networks, and the transit agent belonging to an external communication network excluding the first LAN and the second LAN. The method includes sending, by the remote debugging client, debugging information to the debugger agent; acquiring, by the debugger agent, a process identifier corresponding to the remote debugging client, a receive port identifier, and keyword information corresponding to the debugger agent; and encapsulating the process identifier corresponding to the remote debugging client, the receive port identifier, the keyword information corresponding to the debugger agent, and the debugging information in a packet, and sending the packet to the transit agent; performing, by the transit agent, decapsulation processing on the packet to obtain the keyword information corresponding to the debugger agent, determining, according to a stored mapping table, the debuggee agent that has a correspondence to the debugger agent, and forwarding the packet to the debuggee agent that has a correspondence to the debugger agent; performing, by the debuggee agent, decapsulation processing on the packet to obtain the debugging information, the process identifier corresponding to the remote debugging client, and the receive port identifier, and sending, according to the receive port identifier, the debugging information to a corresponding port of the remote debugging server corresponding to the process identifier; and performing, by the remote debugging server, debugging according to the debugging information.
[0009] Another aspect of present disclosure provides a system for implementing remote debugging. The system includes a remote debugging client, a debugger agent, a transit agent, a debuggee agent, and a remote debugging server. The remote debugging client and the debugger agent both belong to a first LAN. The debuggee agent and the remote debugging server both belong to a second LAN, and the second LAN and the first LAN are different communication networks. The transit agent belongs to an external communication network excluding the first LAN and the second LAN. The remote debugging client is configured to send debugging information to the debugger agent. The debugger agent is configured to acquire a process identifier corresponding to the remote debugging client, a receive port identifier, and keyword information corresponding to the debugger agent; and to encapsulate the process identifier corresponding to the remote debugging client, the receive port identifier, the keyword information corresponding to the debugger agent, and the debugging information in a packet, and to send the packet to the transit agent. The transit agent is configured to perform decapsulation processing on the packet to obtain the keyword information corresponding to the debugger agent, to determine, according to a stored mapping table, the debuggee agent that has a correspondence to the debugger agent, and to forward the packet to the debuggee agent that has the correspondence to the debugger agent. The debuggee agent is configured to perform decapsulation processing on the packet to obtain the debugging information, the process identifier corresponding to the remote debugging client, and the receive port identifier, and to send, according to the receive port identifier, the debugging information to a corresponding port of the remote debugging server corresponding to the process identifier. The remote debugging server is configured to perform debugging according to the debugging information.
[0010] According to the method and the system for implementing remote debugging provided by the embodiments of the present invention, a transit agent, a debugger agent, and a debuggee agent are configured in a remote debugging system, where the transit agent may forward, according to a stored mapping table, information sent by the debugger agent and the debuggee agent to transmit information between a remote debugging client and a remote debugging server that are in different LANs. Compared with the existing technology in which remote debugging can be implemented only in a same LAN, the embodiments of the present invention can implement remote debugging across different LANs to provide applicability of the remote debugging.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] To describe the technical solutions in the embodiments of the present invention or in the existing technology more clearly, the following briefly introduces the accompanying drawings required for describing the embodiments or the existing technology. Apparently, the accompanying drawings in the following description show merely some embodiments of the present invention, and a person of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts.
[0012] FIG. 1 is a flowchart of a method for implementing remote debugging according to first exemplary embodiment of the present invention;
[0013] FIG. 2 is a flowchart of a method for establishing a mapping relationship between a debugger agent and a debuggee agent according to the first exemplary embodiment of the present invention;
[0014] FIG. 3 is a flowchart of a method for synchronizing a port state according to the first exemplary embodiment of the present invention; and
[0015] FIG. 4 is a block diagram of a system for implementing remote debugging according to second exemplary embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
[0016] The following clearly and completely describes the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are merely some but not all of the embodiments of the present invention. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present disclosure.
Embodiment 1
[0017] This exemplary embodiment of the present invention provides a method for implementing remote debugging using a remote debugging system. The remote debugging system includes a remote debugging client, a debugger agent, a transit agent, a debuggee agent, and a remote debugging server. The remote debugging client and the debugger agent both belong to a first LAN, the debuggee agent and the remote debugging server both belong to a second LAN, the second LAN and the first LAN are different communication networks, and the transit agent belongs to an external communication network excluding the first LAN and the second LAN. The LANs are separated by using a corresponding gateway.
[0018] In the exemplary system, the transit agent is used as a core forwarding module, and generally, only one transit agent is configured in one remote debugging system and is configured on an independent server; while one or more debugger agents and debuggee agents may be separately configured, and all the debugger agents and debuggee agents are connected to the same transit agent. For ease of management, it is usually set that one debugger agent is responsible for sending and receiving debugging information of one or more remote debugging clients in one LAN, and one debuggee agent is responsible for sending and receiving debugging information of one or more remote debugging servers in one LAN.
[0019] In the remote debugging system provided by this exemplary embodiment of the present invention, the remote debugging clients and the remote debugging servers are all set based on any one or multiple of remote debugging tools, including, for example, Visual Studio or WinDbg on a Windows platform, and gdb on a Linux platform. The debugger agent may be integrated in a same device with the one or more remote debugging clients, and the debuggee agent may be integrated in a same device with the one or more remote debugging servers.
[0020] Based on the foregoing remote debugging system, this exemplary embodiment of the present invention provides the method for implementing remote debugging. As shown in FIG. 1 , the method includes as follows.
[0021] 101 : The remote debugging client sends debugging information to the debugger agent.
[0022] The debugging information may include, but is not limited to, connection establishment request information, disconnection request information, and debugging data.
[0023] 102 : The debugger agent acquires a process identifier corresponding to the remote debugging client, a receive port identifier, and keyword information corresponding to the debugger agent.
[0024] The process identifier is in a one-to-one correspondence to the remote debugging client. Because the debugger agent needs to be responsible for forwarding and receiving information of multiple remote debugging clients, process identifiers need to be used for differentiation.
[0025] The receive port identifier is used to represent a port at which the remote debugging server receives the debugging information.
[0026] The keyword information is used to identify a correspondence, which is stored in the transit agent, between the debugger agent and the debuggee agent.
[0027] 103 : The debugger agent encapsulates the process identifier corresponding to the remote debugging client, the receive port identifier, the keyword information corresponding to the debugger agent, and the debugging information in a packet.
[0028] A manner of encapsulating the packet is customized in the present disclosure, and therefore, in this exemplary embodiment, multiple independent fields are needed in the packet for separately identifying a type of the packet, the process identifier, the receive port identifier, and debugging data. The type of the packet is used to represent whether the packet is control information or data information, for example, when the debugging information sent by the remote debugging client to the debugger agent is connection establishment request information, the type of the packet should be identified as control information; and when the debugging information sent by the remote debugging client to the debugger agent is debugging data, the type of the packet should be identified as data information. A method for encapsulating the packet may be extended based on the TCP (transmission control protocol).
[0029] 104 : Send the packet to the transit agent.
[0030] 105 : The transit agent performs decapsulation processing on the packet, to obtain the keyword information corresponding to the debugger agent. A method for performing the decapsulation processing corresponds to a method, which is described in step 103 , for performing the encapsulation processing.
[0031] 106 : The transit agent determines, according to a stored mapping table, the debuggee agent that has a correspondence to the debugger agent.
[0032] 107 : The transit agent forwards the packet to the debuggee agent that has the correspondence to the debugger agent.
[0033] 108 : The debuggee agent performs decapsulation processing on the packet, to obtain the debugging information, the process identifier corresponding to the remote debugging client, and the receive port identifier.
[0034] A method for performing the decapsulation processing is the same as that in the description in step 105 , and also corresponds to the method, which is described in step 103 , for performing the encapsulation processing.
[0035] 109 : The debuggee agent sends, according to the receive port identifier, the debugging information to a corresponding port of the remote debugging server corresponding to the process identifier.
[0036] 110 : The remote debugging server performs debugging according to the debugging information.
[0037] A procedure of a method for sending the debugging information by the remote debugging client to the remote debugging server are described in step 101 to step 110 , and the debugging information flows from the remote debugging client to: the debugger agent, the transit agent, the debuggee agent, and the remote debugging server. It should be noted that, in a procedure of a method for sending debugging information by the remote debugging server to the remote debugging client, the debugging information flows from the remote debugging server to the debuggee agent, the transit agent, the debugger agent, and the remote debugging client, and specific implementation of forwarding by functional modules is similar to that of the method described in step 101 to step 110 .
[0038] According to the method for implementing remote debugging provided by this exemplary embodiment of the present invention, a transit agent, a debugger agent, and a debuggee agent are configured in a remote debugging system, where the transit agent completes, according to a stored mapping table, the forwarding of information sent by the debugger agent and the debuggee agent, thereby implementing information transmission between a remote debugging client and a remote debugging server that are located in different LANs. Compared with the existing technology in which remote debugging can be implemented only in a same LAN, this exemplary embodiment of the present invention can implement cross-LAN remote debugging, and provide applicability of the remote debugging.
[0039] Further, this exemplary embodiment of the present invention provides a method for establishing a mapping relationship between the debugger agent and the debuggee agent, for setting a mapping table of a transit device. The method is performed before step 101 . As shown in FIG. 2 , the method specifically includes the following.
[0040] 201 : The transit agent acquires identifier information of all debuggee agents.
[0041] The identifier information of the debuggee agent may be implemented by using information having an identification function, such as socket. For example, socket of the debuggee agent is 555, and socket of the debugger agent is 444.
[0042] 202 : The transit agent allocates unique keyword information to each debuggee agent.
[0043] The keyword information may be set to natural numbers such as 1 and 2, and for a specific implementation method thereof, reference may be made to Table 1 below.
[0000]
TABLE 1
Mapping Table
Socket of a
Socket of a
Keyword
User
State of a
debuggee
State of a
debugger
information
User IP
name
debuggee
agent
debugger
agent
1
11.11.11.11
Zhangsan
READY
555
0
0
2
22.22.22.22
Lisi
BUSY
666
BUSY
777
3
33.33.33.33
Wangwu
ERROR
888
ERROR
999
[0044] In Table 1, the keyword information is a row identifier of each row, and the identifier information of the debuggee agent and the identifier information of the debugger agent are identified by using socket. The state of the debuggee and the state of the debugger may be indicated by using 0 (meaning “no such a device”), READY (meaning “remote debugging may be performed”), BUSY (meaning “remote debugging is being performed”), or ERROR (meaning “device error”).
[0045] It should be noted that Table 1 is only an example in this exemplary embodiment of the present invention, and in the mapping table, the keyword information, the socket of the debuggee agent, and the socket of the debugger agent must be stored. It may be understood that settings of other entries are not necessary for monitoring and maintenance by a maintainer.
[0046] 203 : The transit agent stores the identifier information of the debuggee agent and the keyword information in the mapping table in a mutually corresponding manner.
[0047] A correspondence between identifier information of a debuggee agent and keyword information may be indicated by using a storage method in the first row in Table 1, that is, a mutual correspondence between identifier information of a debuggee agent and allocated keyword information is indicated by storing the identifier information of the debuggee agent and the allocated keyword information in a same row in Table 1.
[0048] 204 : The debugger agent acquires keyword information selected by a user.
[0049] A specific implementation method for acquiring keyword information selected by a user is as follows and includes: receiving, by the debugger agent, state information of the debuggee agent that is sent by the transit agent, the state information of the debuggee agent including the identifier information of the debuggee agent and the keyword information, that correspond to each other; displaying, by the debugger agent, the state information of the debuggee agent; and receiving, by the debugger agent, the keyword information of the debuggee agent that is input by the user, and determining that the keyword information of the debuggee agent that is input by the user is the keyword information selected by the user.
[0050] 205 : The debugger agent sends the keyword information selected by the user and the identifier information of the debugger agent to the transit agent.
[0051] 206 : The transit agent determines, according to the keyword information, a debuggee agent corresponding to the keyword information selected by the user.
[0052] 207 : The transit agent establishes a mapping relationship among the three of the keyword information selected by the user, identifier information of the debuggee agent corresponding to the keyword information selected by the user, and the identifier information of the debugger agent.
[0053] For storage of the mapping relationship among the three of the keyword information selected by the user, the identifier information of the debuggee agent corresponding to the keyword information selected by the user, and the identifier information of the debugger agent, reference may be made to content recorded in the second row and the third row in Table 1. That is, the keyword information selected by the user, the identifier information of the debuggee agent corresponding to the keyword information selected by the user, and the identifier information of the debugger agent among which the mapping relationship exits are recorded in the same row in Table 1.
[0054] 208 : The transit agent stores the mapping relationship in the mapping table. Further, in this exemplary embodiment, the remote debugging server opens or closes a port to adapt to data transmission in various environments. In this case, the debugger agent must also adjust a port state of the debugger agent correspondingly, to ensure accuracy and security of data transmission with the remote debugging client. This exemplary embodiment of the present invention provides a method for synchronizing a port state. As shown in FIG. 3 , the method includes the following.
[0055] 301 : The debuggee agent determines, when detecting that a state of at least one port of the remote debugging server changes, port identifier information corresponding to the at least one port. A state of a port includes two types: an opened state and a closed state.
[0056] 302 : The debuggee agent performs encapsulation according to a current state of the at least one port, the corresponding port identifier information, and the identifier information of the debuggee agent, to generate port indication information. The port indication information may only represent a current state of one port, or may represent current states of multiple ports at the same time.
[0057] 303 : The debuggee agent sends the port indication information to the transit agent.
[0058] 304 : The transit agent performs decapsulation processing on the port indication information to obtain the keyword information corresponding to the debuggee agent.
[0059] 305 : The transit agent determines, according to the stored mapping table, the debugger agent that has a correspondence to the debuggee agent.
[0060] 306 : The transit agent forwards the port indication information to the debugger agent that has a correspondence to the debuggee agent.
[0061] 307 : The debugger agent determines a to-be-adjusted port according to the port indication information, and adjusts a state of the to-be-adjusted port.
[0062] A method for determining a to-be-adjusted port according to the port indication information may include: directly adjusting, according to the port identifier information carried in the port indication information, a port that has the same port identifier information as the port indication information.
[0063] According to the method for implementing remote debugging provided by this exemplary embodiment of the present invention, a transit agent, a debugger agent, and a debuggee agent are configured in a remote debugging system, where the transit agent completes, according to a stored mapping table, forwarding of information sent by the debugger agent and the debuggee agent, thereby implementing information transmission between a remote debugging client and a remote debugging server that are in different LANs. Compared with the existing technology in which remote debugging can be implemented only in a same LAN, this exemplary embodiment of the present invention can implement cross-LAN remote debugging, and provide applicability of the remote debugging.
Embodiment 2
[0064] This exemplary embodiment of the present invention provides a system for implementing remote debugging. As shown in FIG. 4 , the remote debugging system includes a remote debugging client 41 , a debugger agent 42 , a transit agent 43 , a debuggee agent 44 , and a remote debugging server 45 , where the remote debugging client 41 and the debugger agent 42 both belong to a first LAN, the debuggee agent 44 and the remote debugging server 45 both belong to a second LAN, the second LAN and the first LAN are different communication networks, and the transit agent 43 belongs to an external communication network excluding the first LAN and the second LAN. The LANs are separated by using corresponding gateways.
[0065] The remote debugging client 41 is configured to send debugging information to the debugger agent 42 .
[0066] The debugger agent 42 is configured to acquire a process identifier corresponding to the remote debugging client 41 , a receive port identifier, and keyword information corresponding to the debugger agent 42 ; and to encapsulate the process identifier corresponding to the remote debugging client 41 , the receive port identifier, the keyword information corresponding to the debugger agent 42 , and the debugging information in a packet, and to send the packet to the transit agent 43 .
[0067] The transit agent 43 is configured to perform decapsulation processing on the packet to obtain the keyword information corresponding to the debugger agent 42 , to determine, according to a stored mapping table, the debuggee agent 44 that has a correspondence to the debugger agent 42 , and to forward the packet to the debuggee agent 44 that has the correspondence to the debugger agent 42 .
[0068] The debuggee agent 44 is configured to perform decapsulation processing on the packet to obtain the debugging information, the process identifier corresponding to the remote debugging client 41 , and the receive port identifier, and to send, according to the receive port identifier, the debugging information to a corresponding port of the remote debugging server 45 corresponding to the process identifier.
[0069] The remote debugging server 45 is configured to perform debugging according to the debugging information.
[0070] Optionally, the debugging information includes connection establishment request information, disconnection request information, and debugging data.
[0071] Optionally, the transit agent 43 is further configured to acquire identifier information of all debuggee agents 44 , to allocate unique keyword information to each debuggee agent 44 , and to store a correspondence between the identifier information of the debuggee agent 44 and the keyword information in the mapping table.
[0072] The debugger agent 42 is further configured to acquire keyword information selected by a user, and to send the keyword information selected by the user and the identifier information of the debugger agent 42 to the transit agent 43 .
[0073] The transit agent 43 is further configured to determine, according to the keyword information, a debuggee agent corresponding to the keyword information selected by the user, and establish a mapping relationship among the three of the keyword information selected by the user, identifier information of the debuggee agent corresponding to the keyword information selected by the user, and the identifier information of the debugger agent 42 , and to store the mapping relationship in the mapping table.
[0074] Optionally, the debugger agent 42 is specifically configured to enable the debugger agent 42 to receive state information of the debuggee agent 44 that is sent by the transit agent 43 , the state information of the debuggee agent 44 including the correspondence between the identifier information of the debuggee agent 44 and the keyword information; to display the state information of the debuggee agent 44 ; and to receive the keyword information of the debuggee agent 44 that is input by the user, and to determine that the keyword information of the debuggee agent 44 that is input by the user is the keyword information selected by the user.
[0075] Optionally, the debuggee agent 44 is configured to determine, when detecting that a state of at least one port of the remote debugging server 45 changes, port identifier information corresponding to the at least one port, to perform encapsulation according to a current state of the at least one port, the corresponding port identifier information, and the identifier information of the debuggee agent 44 , to generate port indication information, and to send the port indication information to the transit agent 43 .
[0076] The transit agent 43 is configured to perform decapsulation processing on the port indication information to obtain the keyword information corresponding to the debuggee agent 44 , to determine, according to the stored mapping table, the debugger agent 42 that has a correspondence to the debuggee agent 44 , and to forward the packet to the debugger agent 42 that has the correspondence to the debuggee agent 44 .
[0077] The debugger agent 42 is further configured to determine a to-be-adjusted port according to the port indication information, and to adjust a state of the to-be-adjusted port.
[0078] According to the system for implementing remote debugging provided by this exemplary embodiment of the present invention, a transit agent, a debugger agent, and a debuggee agent are configured in a remote debugging system, where the transit agent completes, according to a stored mapping table, forwarding of information sent by the debugger agent and the debuggee agent, thereby implementing information transmission between a remote debugging client and a remote debugging server that are in different LANs. Compared with the existing technology in which remote debugging can be implemented only in a same LAN, this exemplary embodiment of the present invention can implement cross-LAN remote debugging, and provide applicability of the remote debugging.
[0079] According to the description of the foregoing embodiments, a person skilled in the art may clearly understand that, the present disclosure may be implemented by software in addition to necessary universal hardware and certainly, may also be implemented by hardware. In most circumstances, the former is a better implementation manner. Based on such an understanding, the technical solutions of the present disclosure essentially, or a part contributing to the existing technology may be implemented in a form of a software product. The computer software product is stored in a readable storage medium, such as a floppy disk, a hard disk, or an optical disc of a computer, and includes several instructions for instructing a computer device (which may be a personal computer, a server, a network device, or the like) to perform the methods described in the embodiments of the present invention.
[0080] The foregoing descriptions are merely specific implementation manners of the present disclosure, but are not intended to limit the protection scope of the present disclosure. Any variation or replacement readily figured out by a person skilled in the art within the technical scope disclosed in the present disclosure shall fall within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims. | The present disclosure discloses a method and a system for implementing remote debugging, and relates to the field of communications technologies. The disclosed methods and systems can implement remote debugging across different local area networks (LANs). A transit agent, a debugger agent, and a debuggee agent are configured in a remote debugging system. The transit agent may, according to a stored mapping table, forward information sent by the debugger agent and the debuggee agent, to transmit information between a remote debugging client and a remote debugging server that are in different LANs. | 6 |
CLAIM OF PRIORITY
[0001] The present application claims priority from Japanese application JP 2004-192530 filed on Jun. 30, 2004, the content of which is hereby incorporated by reference into this application.
FIELD OF THE INVENTION
[0002] The present invention relates to a network comprising a packet relay device with a function of virtual router, and more particularly, it relates to a system to reduce multicast traffic flowing within the network, by means of sharing the multicast traffic among multiple virtual routers in a single router.
BACKGROUND OF THE INVENTION
[0003] With speedup in access line, a demand for voice and/or video streaming service is increasing. Currently used streaming service employs a unicast system which transmits from a voice/video server, data packets respectively dedicated to multiple subscriber terminals. Therefore, the voice/video server is forced to transmit a large number of packets, causing problems such that data transmission load is high in the voice/video server, as well as increasing a load on a relay network which relays the large number of packets.
[0004] In view of the situation above, telecommunication carriers, such as CDSP (content delivery service provider), and ISP (Internet Service Provider), now consider employing multicast system for the voice/video streaming service. In the multicast system, the voice/video server transmits only one data packet to multiple subscriber terminals, and a packet relay device within a relay network copies the data packet as appropriate, thereby executing a packet transfer to the multiple subscriber terminals. Therefore, the number of packets transmitted by the voice/video server is suppressed to a small number, and the load onto the server can be reduced. Furthermore, the number of packets flowing in the relay network is also suppressed to a small number and the load onto the relay network can be reduced as well.
[0005] In the meantime, the telecommunication carriers may construct a network employing a virtual router (hereinafter, referred to as “VR”), for the purpose of reducing a cost in building the network or separating traffic among subscribers. VR is a technique to configure a function of multiple virtual routers within one packet transfer device. Since such function of multiple routers can be implemented with one packet transfer device, it is possible to reduce the number of installed routers in the circumstance where multiple routers are required at the same spot.
[0006] For example, as for multiple ISPs, ADSL (Asynchronous Digital Subscriber Line) line service provider or FTTH (Fiber To The Home) line service provider, for providing an access network to connect the ISPs and the subscribers, may be capable of providing a function of routers dedicated to the ISPs, respectively. Alternatively, a telecommunication carrier who offers a wide area IP network service called as IP-VAN (IP Virtual Private Network) allocates a VR to each of customers, thereby providing the VPN service without interference in traffic among customers and establishing communication within each customer only.
[0007] FIG. 2 shows a configuration of a conventional packet relay device in a form of functional block of VR, with which a network adapted for multicast transfer can be constructed, as well as VR function is being installed therein. The packet relay device as shown in FIG. 2 implements VR 61 a and VR 61 b . Each of the VRs is provided with UPLINK information 611 a , 611 b , multicast routing tables 612 a , 612 b , PIM 613 a , 613 b , IGMP PROXY 614 a , 614 b , and the like. Reference numerals 12 a to 12 d denote subscriber terminals, and they are connected to the packet relay device 6 via communication lines. Subscriber terminals requesting to participate in a multicast delivery target group transmit IGMP Report messages 13 a to 13 d to the packet relay device 6 .
[0008] The packet transfer device which has received the IGMP Report messages refers to Uplink information using as a key a multicast group address included in each of the IGMP Report messages, selects an interface connected to a line being upstream of the multicast, and transmits to the upstream router a PIM protocol message to allow the terminal to participate in the multicast group. In FIG. 2 , VR 61 a and VR 61 b respectively receive IGMP Report messages 13 a , 13 b and 13 c , 13 d , and transmit PIM protocol messages 13 e and 13 f to the upstream routers.
[0009] The multicast system has a function to reduce the load on the relay network, but there is a possibility the load on the relay network is increased if the multicast system is employed in the network utilizing a VR. In order to clarify a problem to be solved by the present invention, as a reference example, an example in which a network is constructed using the packet relay device as shown in FIG. 2 and data delivery in the network is preformed through multicast system will be described with reference to FIG. 3 . In FIG. 3 , multicast traffic 32 comprising data packets is delivered from the multicast server 3 , via ISP 41 a , router 2 a , VR 61 a and VR 61 b , and via SP 41 b , router 2 b , VR 61 c and VR 61 d , respectively to the subscriber terminals 12 a to 12 d and 12 e to 12 h . Here, VR 61 a and VR 61 b are located within the packet relay device 6 a , and VR 61 c and VR 61 d are located within the packet relay device 6 b.
[0010] A multicast packet is copied by a router on a path from the multicast server to the subscriber terminal, and then the copy is delivered to the subscriber terminal. In FIG. 3 , a data packet from the multicast server 3 is copied by a router (not illustrated) in the Internet 4 and delivered to the routers 2 a and 2 b . Subsequently, the copied data packets are delivered to VR 61 a and VR 61 c from the router 2 a , and another copied data packets are delivered to VR 61 b and VR 61 d from the router 2 b.
[0011] In the multicast delivery, it is desirable to carry out copying in a router located as close as possible to a subscriber, thereby reducing the number of data packets transferred within the network and also reducing the load onto the relay network. However, in the example of FIG. 3 , the data packets belonging to the identical multicast delivery (packets having the same destination address and data) are redundantly delivered from the router 2 a and the router 2 b , to the VR 61 a and VR 61 b in the packet relay device 6 a , and to the VR 61 c and VR 61 d in the packet relay device 6 b.
[0012] The situation above occurs since the VRs with conventional function have to operate independently even if they are located within the same packet relay device, and the multicast traffic cannot be shared between the VRs. Therefore, as it is shown in FIG. 3 , the router 2 a and the router 2 b have to transmit the multicast traffic to all the VRs within the packet relay devices 6 a and 6 b , increasing the load onto the relay network.
SUMMARY OF THE INVENTION
[0013] Considering the problem above, the object of the present invention is to provide a communications network when a multicast system is utilized in a network comprising a packet relay device mounting VR function, the communications network being capable of reducing the load onto a relay network lower than before, and a packet relay device which is capable of implementing the communications network.
[0014] When a network has been configured employing a packet transfer device with the VR function, for example, in the network having the configuration as shown in FIG. 3 , in order to suppress to the minimum the number of multicast packets via the relay network 5 , it is sufficient to transmit one packet to each of the packet relay devices 6 a and 6 b , from either of the routers 2 a and 2 b , the packet being copied within each of the packet relay devices 6 a and 6 b , shared between the VRs, and to transmit those copied packets to the subscriber terminals.
[0015] Therefore, in the present invention, packet transfer across the VRs within the packet relay device can be executed, thereby reducing the number of multicast packets via the relay network. Specifically, the present invention allows a multicast routing table held by each VR to register a line interface identifier of another VR as outgoing line interface information indicating a destination address of the packet. Here, the multicast routing table includes information comprising a combination of a multicast group address and multiple line interface identifiers. When the VR transfers a multicast packet, the VR refers to the multicast routing table using as a key the multicast group address held by the packet, and obtains an outgoing line interface identifier to transmit the packet.
[0016] In the case of conventional VR, each VR operates independently. Therefore, it has been imperative that the outgoing interface identifier of the multicast routing table held by each VR corresponds to a line interface identifier belonging to the VR itself which holds the multicast routing table. On the other hand, the VR according to the present invention allows an interface identifier indicating a line interface of another VR to be registered as an outgoing line interface identifier. Accordingly, a multicast packet received by an arbitrary one VR within the same packet relay device can be shared among multiple VRs within the same relay device.
[0017] By configuring a network by employing the packet relay device implementing the features above, traffic in multicast packet transfer is concentrated, whereby the traffic volume can be reduced than before. Internal configuration of the packet relay device as described above and details of a packet transfer method will be explained in the following preferred embodiments of the present invention.
[0018] According to the present invention, as for packet relay devices arranged dispersedly in subscriber accommodation stations or the like, it is possible to share the multicast traffic among VRs within a single packet relay device, thereby reducing the multicast traffic in a multicast packet relay network.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a schematic diagram showing an example of multicast delivery through an access network employing a router adapted for VR according to the present invention;
[0020] FIG. 2 is a conceptual diagram showing an existing router adapted for VR;
[0021] FIG. 3 is a schematic diagram showing an example of multicast delivery through an access network employing an existing router adapted for VR;
[0022] FIG. 4 is a schematic diagram showing a hardware configuration of the router adapted for VR according to the present invention;
[0023] FIG. 5 is conceptual diagram of the router adapted for VR according to the present invention;
[0024] FIG. 6 shows Uplink information;
[0025] FIG. 7 shows Uplink VR information;
[0026] FIG. 8 shows a multicast routing table of the router adapted for VR according to the present invention;
[0027] FIGS. 9A and 9B show multicast routing tables of the existing router adapted for VR;
[0028] FIG. 10 shows VR configuration information;
[0029] FIG. 11 shows an operational flowchart of the router adapted for VR according to the present invention;
[0030] FIG. 12 shows a conceptual diagram of multicast by the router adapted for VR according to the present invention;
[0031] FIG. 13 shows an IGMP message format;
[0032] FIG. 14 shows a conceptual diagram of multicast by the existing router adapted for VR;
[0033] FIG. 15 shows a conceptual diagram of a router adapted for VR according to another embodiment of the present invention;
[0034] FIGS. 16A and 16B show multicast routing tables of a router adapted for VR according to another embodiment of the present invention; and
[0035] FIG. 17 shows a conceptual diagram of multicast by a router adapted for VR according to another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
[0036] Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be explained. FIG. 1 is a configuration diagram of Internet access network (hereinafter, referred to as “access network”) which has been constructed by applying packet relay devices 1 a , 1 b according to the present embodiment, to routers for accommodating subscriber circuits. The packet relay devices 1 a , 1 b are arranged dispersedly in a subscriber accommodation station on the subscriber side in the access network, and the packet relay devices respectively accommodates subscriber terminals 12 a to 12 d , and 12 e to 12 h . In FIG. 1 , the packet relay device 1 a includes therein VR 11 a and VR 11 b , and the packet relay device 1 b includes therein VR 11 c and VR 11 d . The VR 11 a and VR 11 c are allocated to ISP 41 a , and the VR 11 b and VR 11 d are allocated to ISP 41 b.
[0037] With this configuration, it is not necessary for the subscriber accommodation station to install routers with respect to each ISP, whereby the number of installed routers are reduced. The ISP 41 a is connected to VR 11 a in the packet relay device 1 a and VR 11 c in the packet relay device 1 b , via the router 2 a and the relay network 5 . The ISP 41 b is connected to VR 11 b in the packet relay device 1 a and VR 11 d in the packet relay device 1 b , via the router 2 b and the relay network 5 . The VR 11 a accommodates the subscriber terminals 12 a and 12 b , the VR 11 b accommodates the subscriber terminals 12 c and 12 d . Furthermore, VR 11 c accommodates the subscriber terminals 12 e and 12 f , the VR 11 d accommodates the subscriber terminals 12 g and 12 h . The relay network 5 may be a wide area network, for example, constructed by ATM (Asynchronous Transfer Mode) network and the like.
[0038] FIG. 1 shows an example that multicast server 3 within the Internet 4 performs multicast data delivery to the subscriber terminals 12 a to 12 h . Multicast traffic 31 from the multicast server 3 goes through the ISP 41 a , router 2 a , relay network 5 , and then it is transmitted to the VR 11 a in the packet relay device 1 a , and to the VR 11 c in the packet relay device 1 b . Subsequently, the multicast traffic 31 is copied between the VR 11 a and VR 11 b within the packet relay device 1 a , and also it is copied between the VR 11 c and VR 11 d within the packet relay device 1 b . Then, the copied multicast traffic is delivered from VR 11 a , VR 11 b , VR 11 c , and VR 11 d to the subscribers 12 a to 12 h.
[0039] Here are two multicast traffic flows which pass through the relay network 5 , i.e., a traffic flow from the router 2 a to the VR 11 a in the packet relay device 1 a , and a traffic flow from the router 2 a to the VR 11 c in the packet relay device 1 b . In general, when there is m number of packet relay devices, the number of multicast traffic flows passing through the relay network 5 is m. It is to be noted that multiple number of VRs for receiving the multicast packet may exist among the VRs mounted on the packet relay device 1 a or 1 b as shown in FIG. 1 . Furthermore, VR prepared for receiving is not fixed constantly, and it may be changed according to a type of the multicast packet. In FIG. 7 , for example, the VR for receiving the multicast addressed to MC address 1 is defined as VR 1 . When there is a request from a subscriber to participate in the multicast addressed to MC Address 1 , Uplink VR information is referred to, so as to inform an upstream router of the request. Consequently, the VR 1 becomes the VR for receiving the multicast. As to the Uplink VR information, there will be a detailed explanation in the following, with reference to FIG. 7 .
[0040] In order to see an effect brought about by reducing the traffic in the network as shown in FIG. 1 , traffic volume in the network as shown in FIG. 3 will be explained as a comparative example. FIG. 3 is a configuration diagram showing an access network constructed by applying to a subscriber accommodation station, conventional packet relay devices 6 a , 6 b which do not have VR function as provided by the present embodiment. The network configuration in FIG. 3 is the same as that of FIG. 1 , except the packet relay devices 6 a and 6 b . Similar to the case of FIG. 1 , there is shown an example to perform multicast data delivery from the multicast server 3 within the Internet 4 to the subscriber terminals 12 a to 12 h . Here, the multicast traffic 32 from the multicast server 3 branches out within the Internet 4 , and each reaches ISP 41 a and ISP 41 b.
[0041] From the ISP 41 a , the multicast traffic 3 . 2 goes through the router 2 a and the relay network 5 , and then it is transmitted to the VR 61 a in the packet relay device 6 a and to the VR 61 c in the packet relay device 6 b . From the ISP 41 b , the multicast traffic is transmitted to the VR 61 b in the packet relay device 6 a , and the VR 61 d in the packet relay device 6 b . Then, the multicast traffic is delivered to the subscriber terminals 12 a and 12 b from the VR 61 a in the packet relay device 6 a , to the subscriber terminals 12 c and 12 d from the VR 61 b , to the subscriber terminals 12 e and 12 f from the VR 61 c in the router 6 b , and to the subscriber terminals 12 g and 12 h from the VR 61 d.
[0042] Here, there are four multicast traffic flows which pass through the relay network 5 , i.e., a traffic flow from the router 2 a to the VR 61 a , a traffic flow from the router 2 a to the VR 61 c , a traffic flow from the router 2 b to the VR 61 b , and a traffic flow from the router 2 b to the VR 61 d . In general, if there is m number of packet relay devices and n number of ISPs, the number of multicast traffic flows passing through the relay network 5 is m×n.
[0043] As described above, it is found that by constructing a network by employing the packet relay devices 1 a , 1 b having the multicast function according to the present embodiment, the number of traffic flows through the relay network 5 can be reduced to m from m×n.
[0044] Next, a configuration of the packet relay device according to the present embodiment will be explained. FIG. 4 shows a schematic diagram of a hardware configuration of the packet relay device 1 a or 1 b according to the present embodiment. The packet relay device according to the present embodiment comprises a control function unit 81 , a memory unit 82 , and a packet transfer function unit 83 , and these units are connected via a control bus. The memory unit 82 holds the aforementioned Uplink information 111 , the multicast routing table 112 , and Uplink VR information 115 . Furthermore, the memory unit 82 holds VR configuration information 821 indicating VR configuration. When the packet transfer function unit 83 receives a multicast data packet via the line interface units 84 a to 84 e , the packet transfer function unit 83 refers to the multicast routing table 112 , and transfers the data packet to the line interface indicated by the outgoing IF identifier in the table. At this stage, if there are multiple line interfaces indicated by the outgoing IF identifier, the packet transfer function unit 83 copies the data packet and thus copied packets are transmitted from those line interfaces respectively.
[0045] FIG. 5 shows a functional block diagram of the multicast packet relay device according to the present embodiment. In addition, FIG. 5 shows a procedure for a subscriber terminal to participate in a target of multicast delivery in the packet relay device 1 according to the present embodiment. The packet relay device according to the present embodiment includes VRs 11 a and 11 b . The VR 11 comprises Uplink information 111 a , multicast routing tables 112 a , PIM-SM function 113 a , IGMP Proxy function 114 a , and Uplink VR information 115 a . The VR 11 b comprises Uplink information 111 b , multicast routing tables 112 b , PIM-SM function 113 b , IGMP Proxy function 114 b , and Uplink VR information 115 b . As the outgoing interface identifier defined in each of the multicast routing tables 112 a , 112 b , it is possible to register not only a line interface identifier belonging to the VR holding the multicast routing table, but also a line interface identifier of arbitrary VR.
[0046] The packet relay devices 1 a , 1 b according to the present embodiment hold Uplink VR information to indicate a VR which shares a multicast packet. The Uplink VR information is information comprising a combination of multicast group address and VR identifier. Here, the VR identifier is information which specifies a VR having a line interface for receiving a multicast packet holding the multicast group address. In other words, it is information which indicates a VR having a line interface serving as upstream of the multicast. In the packet relay device according to the present embodiment, the Uplink VR information is appropriately set in each VR, thereby allowing the multicast packet to be shared among the VRs.
[0047] Transferring multicast packets is carried out on the basis of the multicast routing table. A VR which received a multicast delivery request transmitted by a subscriber terminal notifies an upstream router of the request, and simultaneously records in the multicast routing table a line interface identifier to connect the multicast group address with the subscriber terminal, whereby the multicast routing table is created. The multicast group address is included in the multicast delivery request.
[0048] In addition, when the VR implemented by the packet relay devices 1 a , 1 b according to the present embodiment receives a multicast delivery request, the VR refers to the Uplink VR information using as a key the multicast group address included in the request, and passes to a VR indicated by thus obtained VR identifier, the multicast delivery request and a line interface identifier which received the request. The VR which has been passed the multicast delivery request and the line interface identifier, processes the multicast delivery request, and registers in the multicast routing table the multicast group address and the line interface identifier thus passed. Then, the VR performs multicast protocol processing such as IGMP (Internet Group Management Protocol) Proxy function, or PIM (Protocol Independent Multicast), and newly creates a multicast delivery request, followed by transmitting the request from the line interface being an upstream of the multicast.
[0049] FIG. 6 shows Uplink information 111 a , 111 b respectively held by the VRs 11 a and 11 b in the packet relay device 1 according to the present embodiment. The Uplink information is information indicating a line as a multicast upstream, and comprises a combination of multicast group address 6111 and Uplink interface identifier 6112 .
[0050] FIG. 7 shows an example of Uplink VR information 115 a , 115 b respectively held by the VRs 11 a , 11 b in the packet relay device 1 according to the present embodiment. The Uplink VR information comprises a combination of multicast group address 1111 and VR number 1112 . Upon receipt of an IGMP Report message from a subscriber terminal, each VR refers to the Uplink VR information using as a key the multicast group address set in the Group Address field of the IGMP Report message, identifies a VR (upstream VR) for receiving the multicast traffic indicated by the multicast group address, and passes to thus identified VR, the IGMP group message and an identifier of the line interface which received the message.
[0051] Subsequently, in the VR which received the IGMP Group message and the line interface identifier, PIM protocol processing or IGMP Proxy protocol processing is performed. FIG. 5 shows that the VR 11 b which received the IGMP Report messages 13 c , 13 d refer to the Uplink VR information 114 b , selects the VR 11 a as an upstream VR, and a PIM protocol message or IGMP Report message 13 e is transmitted.
[0052] The packet relay device according to the present embodiment performs a multicast control processing by use of the Uplink VR information as described above, whereby a multicast routing table across the VRs is created. FIG. 8 shows an example of the multicast routing table 112 a of the VR 11 a . In FIG. 8 , the multicast group address MC Address 1 is associated with the transmission interfaces, line interface identifiers 1 , 2 , belonging to the VR 11 a , and the line interface identifiers 3 , 4 , belonging to the VR 11 b . The VR 11 a transfers a multicast packet according to this routing table.
[0053] For comparison purposes, FIGS. 9A and 9B show an example of multicast routing tables which are used in a conventional packet relay device 6 as shown in FIG. 2 . In this multicast routing table, the multicast group address 6122 is associated with multiple outgoing interface identifiers 6123 serving as transmission interfaces of the multicast packet.
[0054] In the conventional multicast routing table, only the line interface belonging to the VR which holds the multicast routing table can be specified as the transmission interface. On the other hand, the multicast routing table according to the present embodiment can specify a line interface belonging to a VR other than the VR which holds the multicast routing table. Accordingly, multicast transfer across VRs is made possible.
[0055] FIG. 10 shows VR configuration information 821 . The VR configuration information 821 comprises a combination of interface identifier 8211 and VR number 8212 , and indicates a correspondence between the line interface and VR. For example, FIG. 10 shows that the interfaces 1 and 2 belong to the VR having the VR number 1 , and the interfaces 3 and 4 belong to the VR having the VR number 2 . As shown in FIG. 4 , the control function unit 81 is connected to the management terminal 9 . An administrator of the packet relay device uses the management terminal 9 , and sets VR configuration information 821 , Uplink information 111 , and Uplink VR information 115 . The packet transfer function 83 has line interface units 84 a to 84 e , copies multicast packets received from those line interfaces as appropriate, with reference to the multicast routing table 112 , and then, transfers those copied packets to another line interfaces.
[0056] FIG. 11 shows a flow diagram to provide a summary of processing for creating the multicast routing table in the packet relay device 1 according to the present embodiment. By use of the flow diagram, operations of the VR in the packet relay device 1 according to the present embodiment will be explained in the following.
[0057] The VR that has received an IGMP Report message ( 70 ) refers to the Uplink VR information ( 71 ). If the Uplink VR corresponds to own VR, it performs PIM protocol processing or an IGMP Proxy processing ( 72 , 73 ). At this stage, the VR refers to the Uplink information ( 74 ), and transmits a PIM protocol packet or an IGMP Report message to an upstream line ( 75 ). In addition, the VR registers in the multicast routing table, an identifier of the line interface which received the IGMP Report message, as an outgoing interface identifier associated with the multicast group address included in the IGMP Report message ( 76 ).
[0058] On the other hand, if the Uplink VR is another VR, the IGMP Report message thus received is passed to an upstream VR together with the line interface identifier which received the IGMP Report message ( 72 , 78 ). In the upstream VR, a processing for receiving the IGMP Report message is newly performed, by use of the IGMP Report message which has been passed ( 79 ).
[0059] According to the processing as described above, the multicast traffic is shared among VRs within the same packet relay device, and the multicast delivery as shown in FIG. 1 is carried out. In FIG. 1 , at first, the router 2 a transmits multicast packets to the VR 11 a in the router 1 a and to the VR 11 c in the router 1 b . Subsequently, multicast delivery is performed from the VR 11 a to the subscriber terminals 12 a , 12 b accommodated in the VR 11 a , and to the subscriber terminals 12 c , 12 d accommodated in the VR 11 b . Furthermore, multicast delivery is performed from the VR 11 c to the subscriber terminals 12 e , 12 f accommodated in the VR 11 c , and to the subscriber terminals 12 g , 12 h accommodated in the VR 11 d .
[0060] FIG. 12 shows a situation where multicast packets are transmitted to the subscriber terminals 12 c , 12 d accommodated in the VR 11 b , in addition to the subscriber terminals 12 a , 12 b accommodated in the VR 11 a . Next, a method for a subscriber terminal to participate in a multicast group in the multicast packet transfer will be explained.
[0061] FIG. 13 shows a format of IGMP Ver. 2 message. The IGMP Ver. 2 is a multicast control protocol between a subscriber terminal and a packet relay device, currently used most frequently. The IGMP Ver. 2 message includes Type field, Maximum Response Time field, Checksum field, and Group Address field. The IGMP Report message includes a value of 0×16 in the Type field, and multicast group address indicating a participating subscriber terminal group is set in the Group Address field. It is to be noted that Checksum is information used for data error detection. It is also to be noted that the Maximum Response Time field is not used for the IGMP Report message.
[0062] As another type of IGMP message, there are IGMP Leave Group message and IGMP Query message. When a subscriber terminal leaves from a multicast group, the address of the multicast group is set in the Group Address field in the IGMP Leave group message and it is transmitted to the packet relay device. The IGMP Leave Group message has a value of 0×17 in the Type field, and the Max Response Time field is not used.
[0063] The packet relay device accommodating a subscriber terminal transmits an IGMP Query message to the subscriber terminal on regular basis. The subscriber terminal receives the IGMP Query message, and if the multicast group address in the Group Address field of the IGMP Query message indicates the multicast subscriber terminal group to which the subscriber terminal itself belongs, the subscriber terminal transmits an IGMP Report message. As thus described, the packet relay device accommodating the subscriber terminal prompts the subscriber terminal to transmit an IGMP Report message, thereby checking a participation status of the subscriber terminal in the multicast group. The IGMP Query message has a value of 0×11 in Type field, and in the Group Address field, there is set a multicast group address as to which it is inquired whether or not the terminal is participating. Furthermore, in the Max Response Time field, there is a setting of time period permitted until the IGMP Report message is returned from the subscriber terminal.
[0064] In order to implement the multicast function, the VR 11 a and VR 11 b within the packet relay device 1 includes respectively, PIM functions 113 a , 113 b or IGMP Proxy functions 114 a , 114 b , each being a multicast routing protocol to create a multicast routing table. The VR 11 a and VR 11 b further holds respectively, Uplink information 111 a , 111 b required for protocol operations, and the multicast routing tables 112 a , 112 b which are created with those protocols.
[0065] A procedure for creating the multicast routing table, according to PIM function or IGMP Proxy function will be explained in the following. The PIM functions 113 a , 113 b and the IGMP Proxy functions 114 a , 114 b are protocols to create the multicast routing table. Upon receipt of an IGMP Report message from the subscriber terminal, the PIM function refers to Uplink information using as a key the multicast group address included in the IGMP Report message, selects an interface which is connected to a line being upstream of the multicast, and transmits a PIM protocol message to the upstream router for allowing the terminal to participate in the multicast group. In FIG. 5 , the VR 11 a receives the IGMP Report messages 13 a and 13 b , and VR 11 b receives the IGMP Report messages 13 c and 13 d , and PIM protocol message 13 e is transmitted to the upstream router. Here, as for the VR 11 a , the Uplink VR described in the Uplink VR information indicates its own VR. Therefore, the VR 11 a refers to the Uplink information and transmits the PIM protocol message directly from its own VR to the upstream router. However, as for the VR 11 b , since the Uplink VR described in the Uplink VR information indicates the VR 11 a , the PIM protocol message is not transmitted to the upstream router directly from the VR 11 b itself.
[0066] Similarly, when the IGMP Proxy function receives an IGMP Report message from the subscriber terminal, it refers to the Uplink VR information and Uplink information using as a key the multicast group address included in the IGMP Report message, selects an interface connected to the upstream line of the multicast, and transfers the IGMP Report message from the subscriber terminal on the current line to the upstream router.
[0067] There may be considered following modes for setting the Uplink information, i.e., manually setting by an administrator, and automatically setting of a line being the shortest route to the multicast server on the basis of unicast routing information. Since each VR operates as an independent router, Uplink interface identifier which is set in the Uplink interface information 6112 has to be an identifier indicating a line interface belonging to that VR. In addition, the Uplink VR information is information set by the administrator.
[0068] In the conventional VR, the multicast routing table is managed independently with respect to each VR. In FIG. 2 , the VR 61 a has the multicast routing table 612 a , and the VR 61 b has the multicast routing table 612 b . Here, since each VR operates independently, the outgoing interface identifier indicates any of the line interfaces belonging to the VR holding the multicast routing table. As shown in FIG. 14 , the VR 61 a and VR 61 b within the router 6 transfer the multicast packets according to the respective multicast routing tables.
[0069] On the other hand, in the VR according to the present embodiment, the multicast routing table is managed across the VRs. FIG. 5 and FIG. 12 show that the VR 11 a holds the multicast routing table 112 a , and the VR 11 b holds the multicast routing table 112 b . As shown in FIG. 12 , it is possible for any of the multicast routing tables to have an identifier indicating a line interface belonging to a VR which is different from the VR having that multicast routing table. Accordingly, as shown in FIG. 5 and FIG. 12 , the VR 11 a and VR 11 b within the router 1 are allowed to transfer the multicast packets across the VRs.
[0070] In FIG. 6 , the multicast routing table using as a key the multicast group address is illustrated as an example. However, when a protocol which can specify a multicast server is used, such as IGMP v 3 , PIM-SSM (Source Specific Multicast), a combination of a sender address (address of the multicast server) and the multicast group address is used as a key.
[0071] With the packet relay device which performs multicast packet transfer across the VRs, it is possible to carry out a multicast transfer service without increasing the load of the network data packet transfer, even in the network configuration employing VRs.
Second Embodiment
[0072] In the present embodiment, a VR implementation method, in a type of internal link, will be explained. FIG. 15 shows a functional block diagram of the packet relay device according to the present embodiment. In addition, the hardware configuration of the packet relay device according to the present embodiment can be implemented in the same configuration as shown in FIG. 4 . The packet transfer device 9 used in the present embodiment has the same configuration as that of the conventional packet transfer device 6 , except that the packet transfer device 9 has an internal line 92 . In other words, the Uplink information 911 a , 911 b , multicast routing table 912 a , 912 b , PIM-SM functions 913 a , 913 b , IGMP Proxy functions 914 a , 914 b respectively correspond to Uplink information 611 a , 611 b , multicast routing tables 612 a , 612 b , PIM-SM functions 613 a , 613 b , and IGMP Proxy functions 614 a , 614 b of the conventional packet transfer device 6 . The internal line 92 is a logical line to establish connection between the VRs. FIG. 15 shows that the internal line 92 connects the VR 91 a and the VR 91 b within the router 9 .
[0073] With reference to FIGS. 15, 16 , and 17 , an operation of the router adapted for VR according to the present embodiment will be explained. FIG. 15 shows that VR 91 b holds Uplink information 911 b which uses the internal line 92 as a line connecting to the upstream router, and uses the VR 91 a as an upstream VR. In FIG. 15 , the VR 91 b receives IGMP Report messages 13 c and 13 d from the subscriber terminals 12 c , 12 d . The VR 91 b which received the IGMP Report messages 13 c and 13 d performs PIM or IGMP Proxy protocol processing, and creates a multicast routing table. When the PIM function is used, the VR 91 b transmits a PIM protocol message 13 d to the VR 91 a via the internal line 92 . When the IGMP Proxy function is used, the VR 91 b transmits an IGMP Report message to the VR 91 a via the internal line 92 . This processing is the same as the multicast protocol processing performed by a usual router.
[0074] Next, the VR 91 a , which has received the PIM protocol message or the IGMP Report message from the VR 91 b , performs a protocol processing according to the PIM function or IGMP Proxy function, as in the case of the usual router, and transmits the PIM protocol message or the IGMP Report message 13 e to the upstream router.
[0075] FIG. 16A and FIG. 16B show the multicast routing tables 912 a and 912 b in the present embodiment, which are created respectively by the VR 91 a and the VR 91 b according to the procedure as described above. In the multicast routing table 912 a , the internal line 92 is set in the interface information associated with the multicast group address MC Address 1 , and this is a point different from the multicast routing table held by the existing router 6 adapted for VR. In the present embodiment, as shown in FIG. 17 , the multicast routing tables 912 a and 912 b use the line interfaces 1, 2, 3, and 4, so as to transmit the multicast traffic flows to the subscriber terminals 12 a , 12 b , 12 c , and 12 d , respectively.
[0076] In the present embodiment, since an upstream VR is specified by use of the Uplink information, it is not necessary to specify the Uplink VR information, which is required in the first embodiment. Therefore, it is possible for a VR administrator to obtain an effect of the present invention, even if its operation is closer to the operation of a conventional router. | An object of the present invention is to solve a problem that when multicast is utilized in a network configured with virtual routers, traffic in the relay network is increased. According to the present invention, the number of multicast packets via the relay network is reduced by performing a multicast packet transfer across the virtual routers within the same router. Specifically, it is allowed to register in a multicast routing table held by each virtual router, a line interface identifier of another virtual router as outgoing line interface information, whereby multicast packet transfer from a virtual router to another virtual router is made possible. In order to specify a virtual router to share the multicast packet, each virtual router holds information to specify a virtual router having a line interface to receive the multicast traffic indicated by the multicast group address. | 7 |
TECHNICAL FIELD
[0001] The present application relates to a booklet maker or sheet folding apparatus, as would be used in conjunction with a printing or copying apparatus.
BACKGROUND
[0002] Booklet makers and sheet folders are well-known devices for forming folded booklets or folded sheet sets. It is becoming common to include booklet makers and sheet folders in conjunction with office-range copiers and printers (as used herein, a “copier” will be considered a type of “printer”). In basic form, a booklet maker/sheet folder includes a slot for accumulating signature sheets, as would be produced by a printer. In booklet mode, the accumulated sheets, forming the pages of a booklet, are positioned within the stack so that a stapler mechanism and complementary anvil can staple the stack precisely along the intended crease line. In one embodiment, the creased and stapled sheet sets are then pushed, by a blade, completely through crease rolls, to form the final main fold in the finished booklet. The basic hardware of a booklet maker, such as including the crease rolls, can be controlled to provided C- or Z-folds to sheets or sets of sheets as well. The finished booklets or sheets are then accumulated in a tray downstream of the crease rolls.
[0003] Whether the final product of a booklet maker is a multi-page booklet, or a folded sheet or set of sheets, if it is desired to mail the product without an envelope, it is known to place a sticker on an edge of the product to prevent the booklet or folded sheet from opening or unfolding in the mail.
PRIOR ART
[0004] U.S. Pat. No. 5,980,676 discloses a finishing device for a copier or digital printer which places tapes along the edges of output sheet sets.
SUMMARY
[0005] According to one embodiment, there is provided an apparatus for processing sheets, comprising a roller pair forming a main nip therebetween, the roller pair being operable to move at least one sheet through the main nip in a process direction and a reverse direction opposite the process direction. A sticker applicator is operatively disposed upstream of the main nip along the process direction. A control system, operative of the roller pair and the main nip, causes the roller pair to move a sheet in the reverse direction to receive a sticker from the sticker applicator, and then to move the sheet through the main nip in the process direction.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a simplified elevational view of a “finisher module,” including a booklet maker, as would be used with an office-range digital printer.
[0007] FIG. 2 is a simplified elevational view, showing an embodiment of a sticker applicator in conjunction with folding hardware.
DETAILED DESCRIPTION
[0008] FIG. 1 is a simplified elevational view of a “finisher module,” generally indicated as 100 , including a sheet folder and booklet maker, as would be used with an office-range digital printer. Printed signature sheets from the printer 99 are accepted in an entry port 102 . Depending on the specific design of finisher module 100 , there may be numerous paths such as 104 and numerous output trays 106 for print sheets, corresponding to different desired actions, such as stapling, hole-punching and C- or Z-folding. It is to be understood that the various rollers and other devices which contact and handle sheets within finisher module 100 are driven by various motors, solenoids and other electromechanical devices (not shown), under a control system, such as including a microprocessor (not shown), within the finisher module 100 , printer 99 , or elsewhere, in a manner generally familiar in the art. For present purposes what is of interest is the booklet maker generally indicated as 110 , the basic hardware of which can be used in other types of folding as well.
[0009] Booklet maker 110 defines a slot 112 . Slot 112 accumulates signature sheets (sheets each having typically four page images thereon, for eventual folding into pages of the booklet) from the printer 99 . Each sheet is held within slot 112 at a level where a stapler 114 can staple the sheets along a midline of the signatures, the midline corresponding to the eventual crease of the finished booklet. In order to hold sheets of a given size at the desired level relative to the stapler 114 , there is provided at the bottom of slot 112 an elevator 116 , which forms the “floor” of the slot 112 on which the edges of the accumulating sheets rest before they are stapled. The elevator 116 is placed at different locations along slot 112 depending on the size of the incoming sheets.
[0010] As printed signature sheets are output from printer 99 , they accumulate in slot 112 . When all of the necessary sheets to form a desired booklet are accumulated in slot 112 , elevator 116 is moved from its first position to a second position where the midpoint of the sheets are adjacent the stapler 114 . Stapler 114 is activated to place one or more staples along the midpoint of the sheets, where the booklet will eventually be folded.
[0011] After the stapling, elevator 116 is moved from its second position to a third position, where the midpoint of the sheets are adjacent a blade 14 and crease rolls 10 and 12 , which form a crease nip 16 . The action of blade 14 and crease rolls 10 and 12 performs the final folding, and sharp creasing, of the sheets into the finished booklet. Blade 14 contacts the sheet set along the stapled midpoint thereof, and bends the sheet set toward the nip of crease rolls 10 and 12 , which draw all the sheets in and form a sharp crease. The creased and stapled sheet sets are then drawn, by the rotation of crease rolls 10 and 12 , completely through the nip, to form the final main fold in the finished booklet. The finished booklets are then conducted along path 122 and collected in a tray 124 .
[0012] The basic hardware of a finisher as shown in FIG. 1 , especially as regards booklet maker 110 , can also be controlled to create C-, and in some cases, Z-folds in sheets or sets of sheets.
[0013] FIG. 2 is an elevational view of a sticker applicator that can be used with the basic hardware shown in FIG. 1 . As can be seen, downstream of crease rolls 10 , 12 along a basic process direction of the finisher module is what can be called a roller pair 20 , 22 , together forming what can be called a main nip 24 . In this embodiment, the rollers 20 , 22 are selectably controllable (through a control system and motors, not shown) to direct a sheet S disposed in main nip 24 either in the process direction (i.e., toward the output tray, or to the right in the Figure) or, as needed, in a reverse direction opposite the process direction (i.e., toward the crease nip 16 , or toward the left in the Figure). In this way, as part of a process, the rollers 20 , 22 can “back up” a folded sheet or set of sheet some distance as needed at certain times.
[0014] In FIG. 2 , a sheet indicated as S, which in this view has emerged from folding through crease nip 16 and is disposed in main nip 24 , can in practice be a single sheet, or set of sheets, which has been folded once or in a C- or Z-shape, or can be a multi-sheet, and possibly stapled, booklet. (In any case, for present purposes, a booklet or other folded set of sheets will include at least one sheet.) The trailing edge of such a sheet S along the process direction is “open,” or in other words, not a fold line, and therefore, once the sheet exits the system and is mailed, the sheet is liable to unfold. It is therefore desirable to place a sticker over the open, trailing edge of the sheet S, in effect to keep the sheet folded or the booklet closed.
[0015] Disposed between crease rolls 10 , 12 and roller pair 20 , 22 is what can generally be called a sticker applicator 30 . The applicator 30 provides stickers (such as small pieces of paper or tape, having adhesive on one side thereof) and applies the stickers to the trailing edge of a sheet S held in main nip 24 .
[0016] The sticker applicator 30 in this embodiment includes a dispenser having a supply spool 32 for retaining a supply of stickers on substrate such as backing tape, and take-up spool 34 for taking up the tape as sticker are removed. As shown, the sticker-bearing tape is threaded around a pin 36 , which causes a sharp turn in the motion of the backing tape BT; as the backing tape BT makes the sharp turn, a single sticker ST is effectively peeled from the backing tape and disposed along the path of a sheet S. The backing tape BT would typically be pulled by a friction roller nip (not shown) associated with take-up spool 34 . Because of the large variation in diameter of the take-up spool 34 over the course of its use, it is preferably over-driven with a slipping drive. The main body of sticker applicator 30 can be in the form of an easily replaceable cartridge, so that a spent roll of backing tape on take-up spool 34 can be quickly replaced with a new roll of backing tape on supply spool 32 .
[0017] Because a sticker ST must be placed on a trailing edge of a sheet passing mainly through the process direction, the roller pair 20 , 22 is controlled to momentarily “back up” the sheet S so that the trailing edge of the sheet S is pushed against the sticky (toward the right in the Figure) side of the sticker ST. At an appropriate moment, the applicator interposes a sticker ST in a path of a folded sheet S moving in the reverse direction. In one embodiment, the sheet S can be backed up to such an extent that the sticker ST is placed on the trailing edge and the trailing edge is backed up into crease nip 16 , where the sticker ST is folded down by the crease nip 16 over the trailing edge of sheet S. In this embodiment, the crease rolls 10 , 12 function both to perform a main fold in the sheet S as it moves in the process direction and fold the sticker ST when the sheet moves in the reverse direction. Once the sticker ST is placed on and folded over the trailing edge of sheet S, the direction of roller pair 20 , 22 is again reversed to push the sheet through the process direction (to the right in the Figure) and to an output tray as desired.
[0018] In a practical application of the apparatus in FIG. 2 , the spooling of the backing tape BT around pin 36 is coordinated with the motion of a sheet or booklet past sticker applicator 30 so that, at times in the process when the sheet S is moving in the process direction past the sticker applicator 30 , a sticker ST is not peeled off and placed in the path; rather, the sticker ST is peeled from the backing tape and placed in the path only at such time as the roller pair 20 , 22 is “backing up” the sheet S to receive the sticker. This coordination of the actions of applicator 30 (in particular, of take-up spool 34 ) with the motion of a sheet S can be carried out by precise timing of the motion of the hardware, or with a mechanical or optical feedback system (not shown) governing the motion of the backing tape and/or the sheet S. An optical feedback system governing the backing tape BT could exploit, for instance, synchronization marks or holes on the backing tape BT, such as between each sticker ST.
[0019] The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others. | In a finishing apparatus, such as would be used with a copier or high-speed printer, an applicator places stickers on a folded sheet or booklet, to prevent the sheet or booklet from unfolding or opening. At one point in the operation, the folded sheet or booklet is “backed up” in its basic process direction to receive a sticker on its trailing edge, and backed up further so that the sticker is folded over the trailing edge by a pair of crease rolls. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is divisional of U.S. patent application Ser. No. 14/555,220 filed 26 Nov. 2014, which is divisional of U.S. patent application Ser. No. 13/904,587 filed 29 May 2013, now U.S. Pat. No. 9,079,954, and which is a continuation-in-part of PCT International Application No. PCT/US2013/043116, filed 29 May 2013, which claims the benefit of U.S. patent application Ser. No. 13/904,587, filed 29 May 2013, and claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 61/652,549 filed 29 May 2012, all of which are herein specifically incorporated by reference in their entirety.
SEQUENCE LISTING
[0002] This application incorporates by reference the sequence listing submitted in computer readable form as file 8150US02_ST25.txt created on Nov. 26, 2014 (206,400 bytes).
FIELD OF THE INVENTION
[0003] The invention relates to a cell or cells expressing a recombinant stress-response lectin for the improved production of a multi-subunit protein. Specifically, the invention provides a mammalian cell and cell-line derived therefrom containing a gene encoding EDEM2, and which yields antibody at a high titer.
BACKGROUND OF THE INVENTION
[0004] The manufacture of therapeutically active proteins requires proper folding and processing prior to secretion. Proper folding is particularly relevant for proteins, such as antibodies, which consist of multiple subunits that must be properly assembled before secretion. Eukaryotic cells have adapted a system that ensures the proper folding of proteins and the removal of misfolded proteins from the secretory pathway. This system is called the unfolded protein response (UPR) pathway, and it is triggered by the accumulation of misfolded proteins in the endoplasmic reticulum (ER).
[0005] An early event of the UPR is the activation of the transcription factor Xbp1, which in turn activates the transcription of endoplasmic reticulum degradation-enhancing alpha-mannosidase-like protein 2 (EDEM2), a member of the endoplasmic reticulum associated degradation (ERAD) pathway. EDEM2 facilitates the removal of misfolded proteins. The ERAD pathway comprises five steps: (1) chaperone-mediated recognition of malformed proteins, (2) targeting of malformed proteins to the retrotranslocation machinery or E3-ligases, which involves EDEM2, (3) initiation of retrotranslocation; (4) ubiquitylation and further retrotranslocation; and (5) proteosome targeting and degradation.
[0006] Antibodies are multi-subunit proteins comprising two heavy chains and two light chains, which must be properly folded and associated to form a functional heterotetramer. Any improvement in the efficient and accurate processing of the heavy and light chains to improve the yield or titer of functional antibody heterotetramers is desired.
SUMMARY OF THE INVENTION
[0007] Applicants made the surprising discovery that the ectopic expression of EDEM2 in a protein-manufacturing cell line increases the average output of protein per cell, increases the titer of protein secreted into the media, and increases the integrated cell density of production cell lines.
[0008] Thus, in one aspect, the invention provides a cell containing (a) a recombinant polynucleotide that encodes a stress-induced mannose-binding lectin and (b) a polynucleotide that encodes a multi-subunit protein. In some embodiments, the stress-induced mannose-binding lectin is an EDEM2 protein, non-limiting examples of which are provided in Table 1, and the multi-subunit protein is an antibody. In other embodiments, the cell also contains a polynucleotide that encodes the active spliced form of XBP1, non-limiting examples of which are provided in Table 2. In one embodiment, the cell is a mammalian cell, such as a CHO cell used in the manufacture of biopharmaceuticals.
[0009] In another aspect, the invention provides a cell line derived from the cell described in the previous aspect. By “derived from”, what is meant is a population of cells clonally descended from an individual cell and having some select qualities, such as the ability to produce active protein at a given titer, or the ability to proliferate to a particular density. In some embodiments, the cell line, which is derived from a cell harboring the recombinant polynucleotide encoding a stress-induced mannose-binding lectin and a polynucleotide encoding a multi-subunit protein, is capable of producing the multi-subunit protein at a titer of at least 3 grams per liter of media (g/L), at least 5 g/L, or at least 8 g/L. In some embodiments, the cell line can attain an integrated cell density (ICD) that is at least 30% greater, at least 50% greater, at least 60% greater, or at least 90% greater than the integrated cell density attainable by a cell line derived from what is essentially the same cell but without the recombinant polynucleotide encoding the stress-induced mannose-binding lectin.
[0010] In another aspect, the invention provides an isolated or recombinant polynucleotide comprising a nucleic acid sequence encoding an EDEM2 protein, which is operably linked (cis) to a constitutive and ubiquitously expressed mammalian promoter, such as the ubiquitin C promoter. In some embodiments, the EDEM2 protein has the amino acid of SEQ ID NO: 8, or an amino acid sequence that is at least 92% identical to any one of SEQ ID NO: 1-7. In some embodiments, the polynucleotide comprises a nucleic acid sequence of SEQ ID NO: 16. In one particular embodiment, the polynucleotide consists of a nucleic acid sequence of SEQ ID NO: 14; and in another particular embodiment, SEQ ID NO: 15.
[0011] In another aspect, the invention provides an isolated or recombinant polynucleotide comprising a nucleic acid sequence encoding an XBP1 protein, which is operably linked to (in cis) a constitutive and ubiquitously expressed mammalian promoter, such as the ubiquitin C promoter. In some embodiments, the XBP1 protein has the amino acid of SEQ ID NO: 13, or an amino acid sequence that is at least 86% identical to any one of SEQ ID NO: 9-12. In some embodiments, the polynucleotide comprises a nucleic acid sequence of SEQ ID NO: 18. In one particular embodiment, the polynucleotide consists of a nucleic acid sequence of SEQ ID NO: 17.
[0012] In another aspect, the invention provides a cell that contains an EDEM2-encoding polynucleotide, as described in the prior aspect, and a polynucleotide that encodes a multi-subunit protein, such as an antibody. In some embodiments, the cell also contains an XBP1-encoding polynucleotide, as described in the preceding aspect. In one embodiment, the multi-subunit protein is an antibody, and the heavy chain of the antibody comprises an amino acid sequence of SEQ ID NO: 43 and SEQ ID NO: 44, and the light chain of the antibody comprises an amino acid sequence of SEQ ID NO: 45 and SEQ ID NO: 46. In this and several embodiments, each polypeptide subunit of the multi-subunit protein is encoded by a separate polynucleotide. Thus, for example, a polynucleotide encoding an antibody may include a polynucleotide encoding a heavy chain and a polynucleotide encoding a light chain, hence two subunits. In some embodiments, the cell is a Chinese hamster ovary (CHO) cell.
[0013] In one embodiment, the encoded multi-subunit protein is an anti-GDF8 antibody having a heavy chain variable region amino acid sequence of SEQ ID NO: 20 and a light chain variable region amino acid sequence of SEQ ID NO: 22. In one embodiment, the anti-GDF8 antibody comprises a heavy chain having an amino acid sequence of SEQ ID NO: 19 and a light chain having an amino acid sequence of SEQ ID NO: 21. In one embodiment, the polynucleotide that encodes the heavy chain of the anti-GDF8 antibody comprises a nucleic acid sequence of SEQ ID NO: 23; and the polynucleotide that encodes the light chain of the anti-GDF8 antibody comprises a nucleic acid sequence of SEQ ID NO: 25. In one embodiment, the polynucleotide that encodes the heavy chain of the anti-GDF8 antibody consists of a nucleic acid sequence of SEQ ID NO: 24; and the polynucleotide that encodes the light chain of the anti-GDF8 antibody consists of a nucleic acid sequence of SEQ ID NO: 25.
[0014] In another embodiment, the encoded multi-subunit protein is an anti-ANG2 antibody having a heavy chain variable region amino acid sequence of SEQ ID NO: 28 and a light chain variable region amino acid sequence of SEQ ID NO: 30. In one embodiment, the anti-ANG2 antibody comprises a heavy chain having an amino acid sequence of SEQ ID NO: 27 and a light chain having an amino acid sequence of SEQ ID NO: 29. In one embodiment, the polynucleotide that encodes the heavy chain of the anti-ANG2 antibody comprises a nucleic acid sequence of SEQ ID NO: 31; and the polynucleotide that encodes the light chain of the anti-ANG2 antibody comprises a nucleic acid sequence of SEQ ID NO: 33. In one embodiment, the polynucleotide that encodes the heavy chain of the anti-ANG2 antibody consists of a nucleic acid sequence of SEQ ID NO: 32; and the polynucleotide that encodes the light chain of the anti-ANG2 antibody consists of a nucleic acid sequence of SEQ ID NO: 34.
[0015] In another embodiment, the encoded multi-subunit protein is an anti-ANGPTL4 antibody having a heavy chain variable region amino acid sequence of SEQ ID NO: 36 and a light chain variable region amino acid sequence of SEQ ID NO: 38. In one embodiment, the anti-ANGPTL4 antibody comprises a heavy chain having an amino acid sequence of SEQ ID NO: 35 and a light chain having an amino acid sequence of SEQ ID NO: 37. In one embodiment, the polynucleotide that encodes the heavy chain of the anti-ANGPTL4 antibody comprises a nucleic acid sequence of SEQ ID NO: 39; and the polynucleotide that encodes the light chain of the anti-ANGPTL4 antibody comprises a nucleic acid sequence of SEQ ID NO: 41. In one embodiment, the polynucleotide that encodes the heavy chain of the anti-ANGPTL4 antibody consists of a nucleic acid sequence of SEQ ID NO: 40; and the polynucleotide that encodes the light chain of the anti-ANGPTL4 antibody consists of a nucleic acid sequence of SEQ ID NO: 42.
[0016] In another aspect, the invention provides a method of manufacturing a multi-subunit protein, by culturing a cell of the previous aspect in a medium, wherein the multi-subunit protein is synthesized in the cell and subsequently secreted into the medium. In some embodiments, the multi-subunit protein is an antibody, such as for example anti-GDF8, anti-ANG2, anti-ANGPTL4, or an antibody having a heavy chain sequence of SEQ ID NO: 43 and 44, and a light chain sequence of SEQ ID NO: 45 and 46. In some embodiments, the multi-subunit protein attains a titer of at least 3 g/L, at least 5 g/L, at least 6 g/L, or at least 8 g/L. In some embodiments, the cell proliferates in the medium and establishes an integrated cell density of about ≧5×10 7 cell-day/mL, about ≧1×10 8 cell-day/mL, or about ≧1.5×10 8 cell-day/mL.
[0017] In another aspect, the invention provides a multi-subunit protein, which is manufactured according to the method described in the preceding aspect. In one embodiment, the manufactured protein is an antibody. In some embodiments, the antibody consists of a heavy chain, which comprises an amino acid sequence of SEQ ID NO: 43 and SEQ ID NO: 44, and a light chain, which comprises an amino acid sequence of SEQ ID NO: 45 and SEQ ID NO: 46. In one specific embodiment, the manufactured multi-subunit protein is an anti-GDF8 antibody having a heavy chain variable region amino acid sequence of SEQ ID NO: 20 and a light chain variable region amino acid sequence of SEQ ID NO: 22. In another specific embodiment, the manufactured multi-subunit protein is an anti-ANG2 antibody having a heavy chain variable region amino acid sequence of SEQ ID NO: 28 and a light chain variable region amino acid sequence of SEQ ID NO: 30. In yet another specific embodiment, the manufactured multi-subunit protein is an anti-ANGPTL4 antibody having a heavy chain variable region amino acid sequence of SEQ ID NO: 36 and a light chain variable region amino acid sequence of SEQ ID NO: 38.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1A shows consistently higher protein titer (in mg/L) for EDEM2-expressing clonal cell-lines (gray circles) compared to XBP1-expressing clonal cell-lines (black circles).
[0019] FIG. 1B depicts the integrated cell density (cell-days/mL) for EDEM2-expressing clones (gray circles) compared to XBP1-expressing clones (black circles). Each clone (#1-24) expresses the same gene of interest (antibody), under the same regulatory conditions, and expressing either XBP1 (RGC91) or EDEM2 (RGC92) at a transcriptionally active locus.
[0020] FIG. 2A shows the FACS scans (flow cytometry-based autologous secretion trap (FASTR)) of several clones expressing XBP1. Inconsistency in the peaks is indicative of unstable growth (i.e. a variable or heterogeneous mixture) of the cells in the clones tested.
[0021] FIG. 2B shows the FACS scans of several clones expressing EDEM2, having little to no variation in the peaks representative of clonal stability in the clones tested. FIG. 2B depicts the clonal stability of several clonal cell-lines expressing EDEM2 and an antibody of interest.
DESCRIPTION OF THE INVENTION
[0022] Before the present invention is described, it is to be understood that this invention is not limited to particular methods and experimental conditions described, as such methods and conditions may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.
[0023] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. As used herein, the term “about”, when used in reference to a particular recited numerical value or range of values, means that the value may vary from the recited value by no more than 1%. For example, as used herein, the expression “about 100” includes 99 and 101 and all values in between (e.g., 99.1, 99.2, 99.3, 99.4, etc.).
[0024] Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods and materials are now described. All publications mentioned herein are incorporated herein by reference in their entirety.
[0025] As used herein, the term “recombinant polynucleotide”, which is used interchangeably with “isolated polynucleotide”, means a nucleic acid polymer such as a ribonucleic acid or a deoxyribonucleic acid, either single stranded or double stranded, originating by genetic engineering manipulations. A recombinant polynucleotide may be a circular plasmid or a linear construct existing in vitro or within a cell as an episome. A recombinant polynucleotide may be a construct that is integrated within a larger polynucleotide molecule or supermolecular structure, such as a linear or circular chromosome. The larger polynucleotide molecule or supermolecular structure may be within a cell or within the nucleus of a cell. Thus, a recombinant polynucleotide may be integrated within a chromosome of a cell.
[0026] As used herein, the term “stress-induced mannose-binding lectin” refers to a mannose-binding protein, which means a protein that binds or is capable of binding mannose, derivatives of mannose, such as mannose-6-phosphate, or a glycoprotein that expresses mannose or a mannose derivative in its glycocalyx; and whose activity is upregulated during stress. Cellular stress includes inter alia starvation, DNA damage, hypoxia, poisoning, shear stress and other mechanical stresses, tumor stress, and the accumulation of misfolded proteins in the endoplasmic reticulum. Exemplary stress-induced mannose-binding lectins include the EDEM proteins EDEM1, EDEM2 and EDEM3, Yos 9, OS9, and XTP3-B (see Vembar and Brodsky, Nat. Rev. Mol. Cell. Biol. 9(12): 944-957, 2008, and references cited therein).
[0027] As used herein, the term “EDEM2” means any ortholog, homolog, or conservatively substituted variant of endoplasmic reticulum degradation-enhancing alpha-mannosidase-like protein. EDEM2 proteins are generally known in the art to be involved endoplasmic reticulum-associated degradation (ERAD), being up-regulated by Xbp-1 and facilitating the extraction of misfolded glycoproteins from the calnexin cycle for removal. (See Mast et al., Glycobiology 15(4): 421-436, 2004; Olivari and Molinari, FEBS Lett. 581: 3658-3664, 2007; Olivari et al., J. Biol. Chem. 280(4): 2424-2428, 2005; and Vembar and Brodsky 2008, which are herein incorporated by reference.) Exemplary EDEM2 sequences are depicted in Table 1, which is cross-referenced to the Sequence Listing.
[0000]
TABLE 1
Animal
SEQ ID NO:
% id human
% id mouse
% id hamster
Mouse
1
93
100
96
Rat
2
94
98
96
Hamster
3
93
96
100
Human
4
100
93
93
Chimpanzee
5
99
94
93
Orangutan
6
97
92
92
Zebra fish
7
69
70
69
Consensus
8
100
100
100
[0028] As used herein, the term “Xbp1”, also known as XBP1 or X-box binding protein 1, means any ortholog, homolog, or conservatively substituted variant of Xbp1. Xbp1 is a transcription factor and functional element of the UPR. ER stress activates both (1) the transcription factor ATF6, which in turn upregulates the transcription of Xbp1 mRNA, and (2) the ER membrane protein IRE1, which mediates the splicing of the precursor Xbp1 mRNA to produce active Xbp1. As mentioned above, activated Xbp1 in turn upregulates the activity of EDEM2. (See Yoshida et al., Cell Structure and Function 31(2): 117-125, 2006; and Olivari, 2005.) Exemplary Xbp1 amino acid sequences are depicted in Table 2, which is cross-referenced to the Sequence Listing.
[0000]
TABLE 2
Animal
SEQ ID NO
% id human
% id mouse
% id hamster
Mouse
9
86
100
92
Hamster
10
86
92
100
Human
11
100
86
86
Zebra fish
12
47
47
48
Consensus
13
100
100
100
[0029] As used herein, the term “antibody” is generally intended to refer to immunoglobulin molecules comprising four polypeptide chains, two heavy (H) chains and two light (L) chains inter-connected by disulfide bonds, as well as multimers thereof (e.g., IgM); however, immunoglobulin molecules consisting of only heavy chains (i.e., lacking light chains) are also encompassed within the definition of the term “antibody”. Each heavy chain comprises a heavy chain variable region (abbreviated herein as HCVR or VH) and a heavy chain constant region. The heavy chain constant region comprises three domains, CH1, CH2 and CH3. Each light chain comprises a light chain variable region (abbreviated herein as LCVR or VL) and a light chain constant region. The light chain constant region comprises one domain (CL1). The VH and VL regions can be further subdivided into regions of hypervariability, termed complementary determining regions (CDRs), interspersed with regions that are more conserved, termed framework regions (FR). Each VH and VL is composed of three CDRs and four FRs, arranged from amino-terminus to carboxy-terminus in the following order: FR1, CDR1, FR2, CDR2, FR3, CDR3, FR4. An “isolated antibody” or “purified antibody” may be substantially free of other cellular material or chemicals.
[0030] The term “specifically binds”, or the like, means that an antibody or antigen-binding fragment thereof forms a complex with an antigen that is relatively stable under physiologic conditions. Specific binding can be characterized by a dissociation constant of at least about 1×10 −6 M or greater. Methods for determining whether two molecules specifically bind are well known in the art and include, for example, equilibrium dialysis, surface plasmon resonance, and the like. An isolated antibody that specifically binds human GDF8 (for example) may, however, have cross-reactivity to other antigens, such as GDF8 molecules from other species (orthologs).
[0031] Various antibodies are used as examples of multi-subunit proteins secreted by cells harboring the polynucleotide encoding a stress-induced mannose-binding lectin. Those examples include anti-GDF8, anti-ANG2, and anti-ANGPTL4 antibodies. These and similar antibodies are described in US Pat. Apps. No. 20110293630, 20110027286, and 20110159015 respectively, which are incorporated herein by reference.
[0032] As used herein, the term “cell” refers to a prokaryotic or eukaryotic cell capable of replicating DNA, transcribing RNA, translating polypeptides, and secreting proteins. Cells include animal cells used in the commercial production of biological products, such as insect cells (e.g., Schneider cells, Sf9 cells, Sf21 cells, Tn-368 cells, BTI-TN-5B1-4 cells; see Jarvis, Methods Enzymol. 463: 191-222, 2009; and Potter et al., Int. Rev. Immunol. 10(2-3): 103-112, 1993) and mammalian cells (e.g., CHO or CHO-K1 cells, COS or COS-7 cells, HEK293 cells, PC12 cells, HeLa cells, Hybridoma cells; Trill et al., Curr. Opin. Biotechnol. 6(5): 553-560, 1995; Kipriyanov and Little, Mo. Biotechnol. 12(2): 173-201, 1999). In one embodiment, the cell is a CHO-K1 cell containing the described UPR pathway polynucleotides. For a description of CHO-K1 cells, see also Kao et al., Proc. Nat'l. Acad. Sci. USA 60: 1275-1281, 1968.
[0033] As used herein, the term “promoter” means a genetic sequence generally in cis and located upstream of a protein coding sequence, and which facilitates the transcription of the protein coding sequence. Promoters can be regulated (developmental, tissue specific, or inducible (chemical, temperature)) or constitutively active. In certain embodiments, the polynucleotides that encode proteins are operably linked to a constitutive promoter. By “operably linked”, what is meant is that the protein-encoding polynucleotide is located three-prime (downstream) and cis of the promoter, and under control of the promoter. In certain embodiments, the promoter is a constitutive mammalian promoter, such as the ubiquitin C promoter (see Schorpp et al., Nucl. Acids Res. 24(9): 1787-1788, 1996); Byun et al., Biochem. Biophys. Res. Comm. 332(2): 518-523, 2005) or the CMV-IE promoter (see Addison et al., J. Gen. Virol. 78(7): 1653-1661, 1997; Hunninghake et al., J. Virol. 63(7): 3026-3033, 1989), or the hCMV-IE promoter (human cytomegalovirus immediate early gene promoter) (see Stinski & Roehr, J. Virol. 55(2): 431-441, 1985; Hunninghake et al., J. Virol. 63(7): 3026-3033, 1989).
[0034] As used herein, the phrase “integrated cell density”, or “ICD” means the density of cells in a culture medium taken as an integral over a period of time, expressed as cell-days per mL. In some embodiments, the ICD is measured around the twelfth day of cells in culture.
[0035] As used herein, the term “culture” means both (1) the composition comprising cells, medium, and secreted multi-subunit protein, and (2) the act of incubating the cells in medium, regardless of whether the cells are actively dividing or not. Cells can be cultured in a vessel as small as a 25 mL flask or smaller, and as large as a commercial bioreactor of 10,000 liters or larger. “Medium” refers to the culture medium, which comprises inter alia nutrients, lipids, amino acids, nucleic acids, buffers and trace elements to allow the growth, proliferation, or maintenance of cells, and the production of the multi-subunit protein by the cells. Cell culture media include serum-free and hydrolysate-free defined media as well as media supplemented with sera (e.g., fetal bovine serum (FBS)) or protein hydrolysates. Non-limiting examples of media, which can be commercially acquired, include RPMI medium 1640, Dulbecco's Modified Eagle Medium (DMEM), DMEM/F12 mixture, F10 nutrient mixture, Ham's F12 nutrient mixture, and minimum essential media (MEM).
[0036] As used herein, the phrase “conservatively substituted variant”, as applied to polypeptides, means a polypeptide having an amino acid sequence with one of more conservative amino acid substitutions. A “conservative amino acid substitution” is one in which an amino acid residue is substituted by another amino acid residue having a side chain (R group) with similar chemical properties (e.g., charge or hydrophobicity). In general, a conservative amino acid substitution will not substantially change the functional properties of a protein. In cases where two or more amino acid sequences differ from each other by conservative substitutions, the percent or degree of similarity may be adjusted upwards to correct for the conservative nature of the substitution. Means for making this adjustment are well known to those of skill in the art. See, e.g., Pearson (1994) Methods Mol. Biol. 24: 307-331, which is herein incorporated by reference. Examples of groups of amino acids that have side chains with similar chemical properties include 1) aliphatic side chains: glycine, alanine, valine, leucine and isoleucine; 2) aliphatic-hydroxyl side chains: serine and threonine; 3) amide-containing side chains: asparagine and glutamine; 4) aromatic side chains: phenylalanine, tyrosine, and tryptophan; 5) basic side chains: lysine, arginine, and histidine; 6) acidic side chains: aspartate and glutamate, and 7) sulfur-containing side chains: cysteine and methionine. Preferred conservative amino acids substitution groups are: valine-leucine-isoleucine, phenylalanine-tyrosine, lysine-arginine, alanine-valine, glutamate-aspartate, and asparagine-glutamine. Alternatively, a conservative replacement is any change having a positive value in the PAM250 log-likelihood matrix disclosed in Gonnet et al. (1992) Science 256: 1443-45, herein incorporated by reference. A “moderately conservative” replacement is any change having a nonnegative value in the PAM250 log-likelihood matrix.
EMBODIMENTS
The Cell
[0037] In one aspect, the invention provides a cell useful in the production of a protein having therapeutic or research utility. In some embodiments, the protein consists of multiple subunits, which must be properly folded and assembled to produce sufficient quantities of active protein. Antibodies are an example of multi-subunit proteins having therapeutic or research utility. In some embodiments, the cell harbors a recombinant genetic construct (i.e., a polynucleotide) that encodes one or more of the individual subunits of the multi-subunit protein. In other embodiments, the genetic construct encoding the individual polypeptide subunits is naturally occurring, such as for example the nucleic acid sequences encoding the subunits of an antibody in a B cell.
[0038] To facilitate the proper assembly and secretion of the multi-subunit protein, the cell contains a recombinant polynucleotide that encodes a stress-induced mannose-binding lectin, which in some embodiments is a component of the ERAD. In some embodiments, the stress-induced mannose-binding lectin is an endoplasmic reticulum degradation-enhancing alpha-mannosidase-like protein 2 (EDEM2). It is envisioned that any encoded EDEM2 or conservatively-substituted variant can be successfully employed in the instant invention. Table 1 lists some examples of vertebrate EDEM2 proteins. A multiple pairwise comparison of those protein sequences, which was performed using the Clustal W program of Thompson et al., Nucl. Acids Rev. 22(22): 4673-80, 1994 (see also Yuan et al., Bioinformatics 15(10): 862-3, 1999), revealed that each of the disclosed EDEM2 polynucleotide sequences is at least 69% identical to each other EDEM2 sequence. A Clustal W comparison of the disclosed mammalian EDEM2 sequences revealed that each sequence is at least 92% identical to the other. Thus, in some embodiments, the cell contains a polynucleotide that encodes an EDEM2 polypeptide having a sequence that is at least 92% to any one of a mammalian EDEM2. A consensus EDEM2 amino acid sequence was built by aligning a mouse, rat, hamster, chimpanzee, and human EDEM2 polypeptide amino acid sequences. That consensus sequence is depicted as SEQ ID NO: 8. Thus, in some embodiments, the cell contains a polynucleotide that encodes an EDEM2 polypeptide having an amino acid sequence of SEQ ID NO: 8.
[0039] In various embodiments, the cell contains a recombinant polynucleotide that encodes an EDEM2 polypeptide having an amino acid sequence that is at least 92% identical to the mouse EDEM2 (mEDEM2) amino acid sequence; and in a particular embodiment, the polypeptide is mEDEM2 or a conservatively substituted variant thereof.
[0040] In some embodiments, the multi-subunit protein is an antibody, and the cell contains a polynucleotide encoding any one or more of a polypeptide comprising an amino acid sequence of SEQ ID NO: 43, SEQ ID NO: 44, SEQ ID NO: 45, and SEQ ID NO: 46. SEQ ID NO: 43 and 44 each represent consensus sequences of the roughly N-terminal and C-terminal portions, respectively, of particular antibody heavy chains. Thus, the polynucleotide encoding a protein subunit in one embodiment encodes a polypeptide comprising both SEQ ID NO: 43 and SEQ ID NO: 44. SEQ ID NO: 45 and 46 each represent consensus sequences of the roughly N-terminal and C-terminal portions, respectively, of particular antibody light chains. Thus, the polynucleotide encoding a protein subunit in one embodiment encodes a polypeptide comprising both SEQ ID NO: 45 and SEQ ID NO: 46. In some embodiments, in addition to the recombinant polynucleotide encoding the EDEM2 protein, the cell contains at least two polynucleotides, each of which encodes a particular subunit of the multi-subunit protein. For example, and as exemplified below, the cell contains a polynucleotide encoding an antibody heavy chain comprising an amino acid sequence of SEQ ID NO: 43 and SEQ ID NO: 44, and another polynucleotide encoding an antibody light chain comprising an amino acid sequence of SEQ ID NO: 45 and SEQ ID NO: 46.
[0041] In some embodiments, the cell, in addition to containing the stress-response polynucleotide and one or more polynucleotides encoding a polypeptide subunit, as described above, also contains a polynucleotide that encodes an unfolded protein response transcription factor that operates upstream of EDEM2. The upstream transcription factor is in some cases the spliced form of an XBP1. It is envisioned that any encoded XBP1 can be successfully employed in the instant invention. Table 2 lists some examples of sequences of vertebrate XBP1 spliced-form polypeptides. A multiple pairwise comparison of those polypeptide sequences, which was performed using Clustal W (Thompson 1994; Yuan 1999), revealed that each of the disclosed spliced XBP1 polynucleotide sequences is at least 48% identical to each other XBP1 sequence. A Clustal W comparison of the disclosed mammalian XBP1 sequences revealed that each sequence is at least 86% identical to the other. Thus, in some embodiments, the cell contains a polynucleotide that encodes a spliced-form of an XBP1 polypeptide having a sequence that is at least 86% to any one of a mammalian spliced XBP1. A consensus XBP1 amino acid sequence was built by aligning a mouse, hamster, and human XBP1 amino acid sequences. That consensus sequence is depicted as SEQ ID NO: 13. Thus, in some embodiments, the cell contains a polynucleotide that encodes an XBP1 polypeptide having an amino acid sequence of SEQ ID NO: 13.
[0042] In various embodiments, the cell contains a polynucleotide that encodes an XBP1 polypeptide having an amino acid sequence that is at least 86% identical to the mouse XBP1 (mXBP1) amino acid sequence (SEQ ID NO: 9); and in a particular embodiment, the polypeptide is mXBP1, or a conservatively substituted variant thereof.
[0043] The invention envisions that any cell may be used to harbor the lectin-encoding polypeptide for the production of a properly folded and active multi-subunit protein. Such cells include the well-known protein production cells such as the bacterium Escherichia coli and similar prokaryotic cells, the yeasts Pichia pastoris and other Pichia and non- pichia yeasts, plant cell explants, such as those of Nicotiana , insect cells, such as Schneider 2 cells, Sf9 and Sf21, and the Trichoplusia ni -derived High Five cells, and the mammalian cells typically used in bioproduction, such as CHO, CHO-K1, COS, HeLa, HEK293, Jurkat, and PC12 cells. In some embodiments, the cell is a CHO-K1 or a modified CHO-K1 cell such as that which is taught in U.S. Pat. Nos. 7,435,553, 7,514,545, and 7,771,997, as well as U.S. Published Patent Application No. US 2010-0304436 A1, each of which is incorporated herein by reference in its entirety.
[0044] In some particular embodiments, the invention provides ex vivo a CHO-K1 cell that contains (1) a mEDEM2-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 16, (2) an XBP1-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 18, (3) an antibody heavy chain-encoding polynucleotide comprising a nucleotide sequence that encodes a polypeptide comprising the amino acid sequences of SEQ ID NO: 43 and 44, and (4) an antibody light chain-encoding polynucleotide comprising a nucleotide sequence that encodes a polypeptide comprising the amino acid sequences of SEQ ID NO: 45 and 46.
[0045] In one particular embodiment, the invention provides ex vivo a CHO-K1 cell that contains (1) a mEDEM2-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 16, (2) an XBP1-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO:18, (3) an antibody heavy chain-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 23, and (4) an antibody light chain-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 25.
[0046] In another particular embodiment, the invention provides ex vivo a CHO-K1 cell that contains (1) a mEDEM2-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 16, (2) an XBP1-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 18, (3) an antibody heavy chain-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 31, and (4) an antibody light chain-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 33.
[0047] In yet another particular embodiment, the invention provides ex vivo a CHO-K1 cell that contains (1) a mEDEM2-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 16, (2) an XBP1-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 18, (3) an antibody heavy chain-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 39, and (4) an antibody light chain-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 41.
[0048] The Cell Line
[0049] In another aspect, the invention provides a cell line, which comprises a plurality of cells descended by clonal expansion from a cell described above. At least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99%, or about 100% of the constituent cells of the cell line contain a recombinant polynucleotide that encodes a stress-induced mannose-binding lectin, which in some embodiments is a component of the ERAD. In some embodiments, the stress-induced mannose-binding lectin is an endoplasmic reticulum degradation-enhancing alpha-mannosidase-like protein 2 (EDEM2). It is envisioned that any encoded EDEM2 or conservatively-substituted variant thereof can be successfully employed in the instant invention. Table 1, as discussed in the previous section, lists some examples of vertebrate EDEM2 proteins. In some embodiments, the constituent cell contains a polynucleotide that encodes an EDEM2 polypeptide having a sequence that is at least 92% identical to any mammalian EDEM2. In some embodiments, the constituent cell contains a polynucleotide that encodes an EDEM2 polypeptide having the mammalian consensus amino acid sequence of SEQ ID NO: 8. In some embodiments, the constituent cell contains a recombinant polynucleotide of SEQ ID NO: 1 or a conservatively substituted variant thereof.
[0050] In some embodiments, the multi-subunit protein that is produced by the cell line is an antibody, and the constituent cell of the cell line contains a polynucleotide encoding any one or more of a polypeptide comprising an amino acid sequence of SEQ ID NO: 43 and SEQ ID NO: 44 (which represent consensus sequences of the N-terminal and C-terminal portions, respectively, of particular antibody heavy chains), and SEQ ID NO: 45 and SEQ ID NO: 46 (which represent consensus sequences of the N-terminal and C-terminal portions, respectively, of particular antibody light chains). In some embodiments, in addition to the recombinant polynucleotide encoding the EDEM2 protein, the constituent cell of the cell line contains at least two polynucleotides, each of which encodes a particular subunit of the multi-subunit protein. For example, the constituent cell contains a polynucleotide encoding an antibody heavy chain comprising an amino acid sequence of SEQ ID NO: 43 and SEQ ID NO: 44, and another polynucleotide encoding an antibody light chain comprising an amino acid sequence of SEQ ID NO: 45 and SEQ ID NO: 46.
[0051] In some embodiments, the constituent cell, in addition to containing the stress-response polynucleotide and one or more polynucleotides encoding a polypeptide subunit, as described above, also contains a polynucleotide that encodes an unfolded protein response transcription factor, which operates upstream of EDEM2, such as a spliced form of an XBP1. It is envisioned that any encoded XBP1 can be successfully employed in the instant invention. Table 2, as discussed in the preceding section, lists some examples of sequences of vertebrate XBP1 spliced-form polypeptides. Clustal W analysis of those sequences revealed that each of the disclosed spliced XBP1 polynucleotide sequences is at least 48% identical to each other XBP1 sequence; and a comparison of the mammalian XBP1 sequences revealed that each sequence is at least 86% identical to the other. Thus, in some embodiments, the constituent cell of the cell line contains a polynucleotide that encodes a spliced-form of an XBP1 polypeptide having a sequence that is at least 86% to any one of a mammalian spliced XBP1. In some embodiments, the constituent cell contains a polynucleotide that encodes an XBP1 polypeptide having a consensus amino acid sequence of SEQ ID NO: 13.
[0052] In various embodiments, the cell contains a polynucleotide that encodes an XBP1 polypeptide having an amino acid sequence that is at least 86% identical to the mouse XBP1 (mXBP1) amino acid sequence (SEQ ID NO: 9); and in a particular embodiment, the polypeptide is mXBP1 of SEQ ID NO: 9, or a conservatively substituted variant thereof.
[0053] The invention envisions that the cell line comprises constituent cells whose parent is selected from a list of well-known protein production cells such as, e.g., the bacterium Escherichia coli and similar prokaryotic cells, the yeasts Pichia pastoris and other Pichia and non- pichia yeasts, plant cell explants, such as those of Nicotiana , insect cells, such as Schneider 2 cells, Sf9 and Sf21, and the Trichoplusia ni -derived High Five cells, and the mammalian cells typically used in bioproduction, such as CHO, CHO-K1, COS, HeLa, HEK293, Jurkat, and PC12 cells. In some embodiments, the cell is a CHO-K1 or a modified CHO-K1 cell, such as that which is taught in U.S. Pat. Nos. 7,435,553, 7,514,545, and 7,771,997, as well as U.S. Published Patent Application No. US 2010-0304436 A1.
[0054] In some embodiments, the cell line, which is cultured in media, is capable of producing the multi-subunit protein and secreting the properly assembled multi-subunit protein into the media to a titer that is at least 3 g/L, at least 5 g/L, or at least 8 g/L.
[0055] Furthermore, the constituent cells of the cell line are capable proliferating in culture to such an extent as to attain an integrated cell density that is about 30% greater than the integrated cell density of a cell line that does not contain the recombinant polynucleotide encoding the stress-induced mannose-binding lectin. In some cases, the cell line is able to attain an integrated cell density that is at least about 50% greater, at least 60% greater, or at least 90% greater than the integrated cell density of a cell line that does not contain the recombinant polynucleotide that encodes a stress-induced mannose-binding lectin. In some embodiments, the integrated cell density of the cell line is assessed after about 12 days in culture.
[0056] In some particular embodiments, the invention provides a cell-line comprising clonally-derived constituent cells, wherein the constituent cell is a CHO-K1 cell that contains (1) a mEDEM2-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 16, (2) an XBP1-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 18, (3) an antibody heavy chain-encoding polynucleotide comprising a nucleotide sequence that encodes a polypeptide comprising the amino acid sequences of SEQ ID NO: 43 and 44, and (4) an antibody light chain-encoding polynucleotide comprising a nucleotide sequence that encodes a polypeptide comprising the amino acid sequences of SEQ ID NO: 45 and 46.
[0057] In one particular embodiment, the invention provides a cell-line comprising clonally-derived constituent cells, wherein the constituent cell is a CHO-K1 cell that contains (1) a mEDEM2-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 16, (2) an XBP1-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 18, (3) an antibody heavy chain-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 23, and (4) an antibody light chain-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 25.
[0058] In another particular embodiment, the invention provides a cell-line comprising clonally-derived constituent cells, wherein the constituent cell is a CHO-K1 cell that contains (1) a mEDEM2-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 16, (2) an XBP1-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 18, (3) an antibody heavy chain-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 31, and (4) an antibody light chain-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 33.
[0059] In yet another particular embodiment, the invention provides a cell-line comprising clonally-derived constituent cells, wherein the constituent cell is a CHO-K1 cell that contains (1) a mEDEM2-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 16, (2) an XBP1-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 18, (3) an antibody heavy chain-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 39, and (4) an antibody light chain-encoding polynucleotide comprising a nucleotide sequence of SEQ ID NO: 41.
[0060] The EDEM2 Polynucleotide
[0061] In another aspect, the invention provides a polynucleotide that encodes an EDEM2 protein. The EDEM2-encoding polynucleotide is recombinant and can be manufactured, stored, used or expressed in vitro, as in a test tube, or an in vitro translation system, or in vivo, such as in a cell, which can be ex vivo, as in a cell culture, or in vivo, as in an organism. In some embodiments, the EDEM2-encoding polynucleotide is within a gene, meaning that it is under the control of and down stream of a promoter, and up stream of a polyadenylation site. The EDEM2-encoding polynucleotide or gene can be within a plasmid or other circular or linear vector. The EDEM2-encoding polynucleotide or gene can be within a circular or linear DNA construct, which can be within a cell as an episome or integrated into the cellular genome.
[0062] As described above, the EDEM2-encoding polynucleotide encodes any ortholog, homolog or conservatively substituted EDEM2 polypeptide of Table 1, or an EDEM2 polypeptide having an amino acid sequence that is at least 92% identical to any one of SEQ ID NO: 1-5 and 8, including the mammalian consensus sequence of SEQ ID NO: 8.
[0063] In some cases, the recombinant or isolated EDEM2-encoding polynucleotide is operably linked to a mammalian promoter. The promoter can be any promoter, but in some cases it is a mammalian promoter, such as for example a ubiquitin C promoter.
[0064] In a particular embodiment, the EDEM2-encoding polynucleotide essentially consists of, from 5′ to 3′, a promoter, such as a ubiquitin C promoter, followed by an optional intron, such as a beta globin intron, followed by an EDEM2 coding sequence, followed by a polyadenylation sequence, such as an SV40 pA sequence. A specific example, which is also a particular embodiment, of such an EDEM2-encoding polynucleotide is described by SEQ ID NO: 16. Conserved variants of that sequence are also envisioned to be embodiments of the invention.
[0065] In some cases, the recombinant EDEM2-encoding polynucleotide is part of a plasmid, which can be linear, circular, episomal, integrated, a static DNA construct, or a vector for delivering the EDEM2 gene or expressing the EDEM2 protein. In one particular embodiment, the plasmid contains (1) an EDEM2 gene, which is under the control of a ubiquitin C promoter and terminates with an SV40 polyadenylation signal, and (2) a selectable marker, such as a polynucleotide encoding a polypeptide that confers resistance to zeocin or a polynucleotide encoding a polypeptide that confers resistance to neomycin, under the control of a promoter, such as an SV40 promoter, and terminated with a polyadenylation sequence, such as a PGK pA sequence. In one particular embodiment, the plasmid comprises, in a circular format running in a 5′ to 3′ direction, a ubiquitin C promoter, a beta globin intron, an EDEM2 coding sequence, an SV40 pA sequence, an SV40 promoter, a neomycin-resistance coding sequence, and a PGK pA sequence. A specific example of this embodiment is exemplified by a plasmid having the sequence of SEQ ID NO: 14. In another particular embodiment, the plasmid comprises, in a circular format running in a 5′ to 3′ direction, a ubiquitin C promoter, a beta globin intron, an EDEM2 coding sequence, an SV40 pA sequence, an SV40 promoter, a zeocin-resistance coding sequence, and a PGK pA sequence. A specific example of this embodiment is exemplified by a plasmid having the sequence of SEQ ID NO: 15.
[0066] The XBP1 Polynucleotide
[0067] In another aspect, the invention provides a polynucleotide that encodes an XBP1 protein. The XBP1-encoding polynucleotide is recombinant and can be manufactured, stored, used or expressed in vitro, as in a test tube, or an in vitro translation system, or in vivo, such as in a cell, which can be ex vivo, as in a cell culture, or in vivo, as in an organism. In some embodiments, the XBP1-encoding polynucleotide is within a gene, meaning that it is under the control of and down stream of a promoter, and up stream of a polyadenylation site. The XBP1-encoding polynucleotide can be within a plasmid or other circular or linear vector. The XBP1-encoding polynucleotide or gene can be within a circular or linear DNA construct, which can be within a cell as an episome, or integrated into the cellular genome.
[0068] As described above, the XBP1-encoding polynucleotide encodes any ortholog, homolog or conservatively substituted XBP1 polypeptide of Table 2, or an XBP1 polypeptide having an amino acid sequence that is at least 86% identical to any one of SEQ ID NO: 9, 10, and 11, including the mammalian consensus sequence of SEQ ID NO: 13.
[0069] In some cases, the recombinant or isolated XBP1-encoding polynucleotide is operably linked to a mammalian promoter. The promoter can be any promoter, but in some cases it is a mammalian promoter, such as for example a ubiquitin C promoter.
[0070] In a particular embodiment, the XBP1-encoding polynucleotide essentially consists of, from 5′ to 3′, a promoter, such as a ubiquitin C promoter, followed by an optional intron, such as a beta globin intron, followed by an XBP1 coding sequence, followed by a polyadenylation sequence, such as an SV40 pA sequence. SEQ ID NO: 18 describes an example of an XBP1-encoding polynucleotide. Conserved variants of that exemplary sequence are also envisioned to be embodiments of the invention.
[0071] In some cases, the recombinant XBP1-encoding polynucleotide is part of a plasmid, which can be linear, circular, episomal, integrated, a static DNA construct, or a vector for delivering the XBP1 gene or expressing the spliced and active XBP1 protein. In one particular embodiment, the plasmid contains (1) an XBP1 gene, which is under the control of a ubiquitin C promoter and terminates with an SV40 polyadenylation signal, and (2) a selectable marker, such as a polynucleotide encoding a polypeptide that confers resistance to zeocin or a polynucleotide encoding a polypeptide that confers resistance to neomycin, under the control of a promoter, such as an SV40 promoter, and terminated with a polyadenylation sequence, such as a PGK pA sequence. In one particular embodiment, the plasmid comprises, in a circular format running in a 5′ to 3′ direction, a ubiquitin C promoter, a beta globin intron, an XBP1 coding sequence, an SV40 pA sequence, an SV40 promoter, a zeocin-resistance coding sequence, and a PGK pA sequence. A specific example of this embodiment is exemplified by a circular plasmid having the sequence of SEQ ID NO: 17.
[0072] The Antibody Heavy and Light Chain-Encoding Polynucleotides
[0073] In another aspect, the invention provides a polynucleotide that encodes an antibody heavy chain polypeptide (HC). The HC-encoding polynucleotide is recombinant and can be manufactured, stored, used or expressed in vitro, as in a test tube, or an in vitro translation system, or in vivo, such as in a cell, which can be ex vivo, as in a cell culture, or in vivo, as in an organism. In some embodiments, the HC-encoding polynucleotide is within a gene, meaning that it is under the control of and down stream from a promoter, and up stream of a polyadenylation site. The HC-encoding polynucleotide may be within a plasmid or other circular or linear vector. The HC-encoding polynucleotide or gene may be within a circular or linear DNA construct, which may be within a cell as an episome or integrated into the cellular genome.
[0074] In some cases, the recombinant or isolated HC-encoding polynucleotide is operably linked to a mammalian promoter. The promoter can be any promoter, but in some cases it is a mammalian promoter, such as for example a ubiquitin C promoter or an hCMV-IE promoter.
[0075] In a particular embodiment, the HC-encoding polynucleotide is an HC gene, which essentially comprises, from 5′ to 3′, a promoter, for example an hCMV-IE promoter, followed by an optional intron, such as a beta globin intron, followed by a heavy chain coding sequence, such as for example a sequence encoding an amino acid sequence of SEQ ID NO: 43 and 44, SEQ ID NO: 19, SEQ ID NO: 27, or SEQ ID NO: 35, followed by a polyadenylation sequence, for example an SV40 pA sequence. A specific example of an HC gene is described by SEQ ID NO: 23, SEQ ID NO: 31, or SEQ ID NO: 39. Conserved variants of any one of these sequences are also envisioned to be embodiments of the invention.
[0076] In some cases, the recombinant HC-encoding polynucleotide is part of a plasmid, which can be linear, circular, episomal, integrated, a static DNA construct, or a vector for delivering the heavy chain gene or expressing the heavy chain sububunit. In one particular embodiment, the plasmid contains (1) an HC gene, which is under the control of an hCMV-IE promoter and terminates with an SV40 polyadenylation signal, and (2) a selectable marker, such as a polynucleotide encoding a polypeptide that confers resistance to hygromycin, under the control of a promoter, such as an SV40 promoter, and terminated with a polyadenylation sequence, such as a PGK pA sequence. In one particular embodiment, the plasmid comprises, in a circular format running in a 5′ to 3′ direction, an hCMV-IE promoter, a beta globin intron, an antibody heavy chain coding sequence (which encodes a HC having an amino acid of SEQ ID NO: 43 and 44, SEQ ID NO: 19, SEQ ID NO: 27, or SEQ ID NO: 35), an SV40 pA sequence, an SV40 promoter, a hygromycin-resistance coding sequence, and a PGK pA sequence. A specific example and particular embodiment of such a plasmid containing an HC gene is described by SEQ ID NO: 24, SEQ ID NO: 32, or SEQ ID NO: 40. Conserved variants of any one of these sequences are also envisioned to be embodiments of the invention.
[0077] In another aspect, the invention provides a polynucleotide that encodes an antibody light chain polypeptide (LC). The LC-encoding polynucleotide is recombinant and can be manufactured, stored, used or expressed in vitro, as in a test tube, or an in vitro translation system, or in vivo, such as in a cell, which can be ex vivo, as in a cell culture, or in vivo, as in an organism. In some embodiments, the LC-encoding polynucleotide is within a gene, meaning that it is under the control of and down stream from a promoter, and up stream of a polyadenylation site. The LC-encoding polynucleotide or gene may be within a plasmid or other circular or linear vector. The LC-encoding polynucleotide or gene may be within a circular or linear DNA construct, which may be within a cell as an episome or integrated into the cellular genome.
[0078] In some cases, the recombinant or isolated LC-encoding polynucleotide is operably linked to a mammalian promoter. The promoter can be any promoter, but in some cases it is a mammalian promoter, such as, e.g., a ubiquitin C promoter or an hCMV-IE promoter.
[0079] In a particular embodiment, the LC-encoding polynucleotide is an LC gene, which essentially comprises, from 5′ to 3′, a promoter, for example an hCMV-IE promoter, followed by an optional intron, such as a beta globin intron, followed by a light chain coding sequence, such as for example a sequence encoding an amino acid sequence of SEQ ID NO: 45 and 46, SEQ ID NO: 21, SEQ ID NO: 29, or SEQ ID NO: 37, followed by a polyadenylation sequence, such as an SV40 pA sequence. A specific example and particular embodiment of such an LC gene is described by SEQ ID NO: 25, SEQ ID NO: 33, or SEQ ID NO: 41. Conserved variants of any one of these sequences are also envisioned to be embodiments of the invention.
[0080] In some cases, the recombinant LC-encoding polynucleotide is part of a plasmid, which may be linear, circular, episomal, integrated, a static DNA construct, or a vector for delivering the light chain gene or expressing the light chain sububunit. In one particular embodiment, the plasmid contains (1) an LC gene, which is under the control of an hCMV-IE promoter and terminates with an SV40 polyadenylation signal, and (2) a selectable marker, such as a polynucleotide encoding a polypeptide that confers resistance to hygromycin, under the control of a promoter, such as an SV40 promoter, and terminated with a polyadenylation sequence, such as a PGK pA sequence. In one particular embodiment, the plasmid comprises, in a circular format running in a 5′ to 3′ direction, an hCMV-IE promoter, a beta globin intron, an antibody light chain coding sequence (which encodes a LC having an amino acid of SEQ ID NO: 45 and 46, SEQ ID NO: 21, SEQ ID NO: 29, or SEQ ID NO: 37), an SV40 pA sequence, an SV40 promoter, a hygromycin-resistance coding sequence, and a PGK pA sequence. A specific example and particular embodiment of such a plasmid containing an LC gene is described by SEQ ID NO: 26, SEQ ID NO: 34, or SEQ ID NO: 42. Conserved variants of any one of these sequences are also envisioned to be embodiments of the invention.
[0081] Methods of Manufacturing Multi-Subunit Proteins
[0082] In another aspect, the invention provides a method for manufacturing a multi-subunit protein by culturing a cell, or a constituent cell of a cell line, which is capable of producing and secreting relatively large amounts of a properly assembled multi-subunit protein, in a medium, wherein the multi-subunit component is secreted into the medium at a relatively high titer. The cell utilized in this manufacturing process is a cell described in the foregoing aspects, which contains an ERAD lectin-encoding polynucleotide described herein.
[0083] Methods of culturing cells, and in particular mammalian cells, for the purpose of producing useful recombinant proteins is well-known in the art (e.g., see De Jesus & Wurm, Eur. J. Pharm. Biopharm. 78:184-188, 2011, and references cited therein). Briefly, cells containing the described polynucleotides are cultured in media, which may contain sera or hydrolysates, or may be chemically defined and optimized for protein production. The cultures may be fed-batch cultures or continuous cultures, as in a chemostat. The cells may be cultured in lab bench size flasks (˜25 mL), production scale-up bioreactors (1-5 L), or industrial scale bioreactors (5,000-25,000 L). Production runs may last for several weeks to a month, during which time the multi-subunit protein is secreted into the media.
[0084] The subject cell has an enhanced ability to produce and secrete properly assembled multi-subunit proteins. In some embodiments, the multi-subunit protein, for example an antibody, is secreted into the media at a rate of at least 94 ρg/cell/day, at least 37 ρg/cell/day, or at least 39 ρg/cell/day. In some embodiments, the multi-subunit protein attains a titer of at least at least 3 g/L, at least 5 g/L, at least 6 g/L, or at least 8 g/L after about twelve days of culture.
[0085] Furthermore, the subject cell has an enhanced ability to proliferate and attain a relatively high cell density, further optimizing productivity. In some embodiments, the cell or cell-line seed train attains an integrated cell density in culture of at least 5×10 7 cell-day/mL, at least 1×10 8 cell-day/mL or at least 1.5×10 8 cell-day/mL.
[0086] Optionally, the secreted multi-subunit protein is subsequently purified from the medium into which it was secreted. Protein purification methods are well-known in the art (see e.g., Kelley, mAbs 1(5):443-452). In some embodiments, the protein is harvested by centrifugation to remove the cells from the liquid media supernatant, followed by various chromatography steps and a filtration step to remove inter alia viruses and other contaminants or adulterants. In some embodiments, the chromatography steps include an ion exchange step, such as cation-exchange or anion-exchange. Various affinity chromatographic media may also be employed, such as protein A chromatography for the purification of antibodies.
[0087] Optionally, the manufacturing method may include the antecedent steps of creating the cell. Thus, in some embodiments, the method of manufacturing the multi-subunit protein comprises the step of transfecting the cell with the vector that encodes the stress-induced mannose-binding lectin, as described above, followed by selecting stable integrants thereof. Non-limiting examples of vectors include those genetic constructs that contain a polynucleotide that encodes an EDEM2 having an amino acid sequence of any one of SEQ ID NO: 1-8, an amino acid sequence that is at least 92% identical to any one of SEQ ID NO: 1-8, or any one of a conservatively substituted variant of SEQ ID NO: 1-8. Useful vectors also include, for example, a plasmid harboring the gene of SEQ ID NO: 16, the plasmid of SEQ ID NO: 15, and the plasmid of SEQ ID NO: 14. One should keep in mind that the plasmid sequences (e.g., SEQ ID NO: 14, 15, 17, 24, 26, 32, 34, 40, and 42) are circular sequences described in a linear manner in the sequence listing. Thus, in those cases, the 3-prime-most nucleotide of the written sequence may be considered to be immediately 5-prime of the 5-prime-most nucleotide of the sequence as written. In the example of the plasmid of SEQ ID NO: 14, transformants are selected through resistance to neomycin; for SEQ ID NO: 15, by selection through ZEOCIN resistance.
[0088] Detailed methods for the construction of polynucleotides and vectors comprising same, are described in U.S. Pat. Nos. 7,435,553 and 7,771,997, which are incorporated herein by reference, and in, e.g., Zwarthoff et al., J. Gen. Virol. 66(4):685-91, 1985; Mory et al., DNA. 5(3):181-93, 1986; and Pichler et al., Biotechnol. Bioeng. 108(2):386-94, 2011.
[0089] The starting cell, into which the vector that encodes the stress-induced mannose-binding lectin is placed, may already contain the constructs or genetic elements encoding or regulating the expression of the subunits of the multi-subunit protein, or XBP1 for those embodiments utilizing XBP1. Alternatively, the vector that encodes the stress-induced mannose-binding lectin may be put inside the cell first, and followed by the other constructs.
[0090] Multi-Subunit Proteins Manufactured by the Process
[0091] In another aspect, the invention provides a multi-subunit protein that is made according to the process disclosed herein. Given the inclusion of one or more elements that facilitate the proper folding, assembly, and post-translational modification of a multi-subunit protein, such as an antibody, one of ordinary skill in the art would reasonably expect such a protein to have distinct structural and functional qualities. For example, an antibody manufactured by the disclosed process is reasonably believed to have a particular glycosylation pattern and a quantitatively greater proportion of non-aggregated heterotetramers.
EXAMPLES
[0092] The following examples are presented so as to provide those of ordinary skill in the art with a complete disclosure and description of how to make and use the methods and compositions of the invention, and are not intended to limit the scope of what the inventors regard as their invention. Efforts have been made to ensure accuracy with respect to numbers used (e.g., amounts, temperature, etc.) but some experimental errors and deviations should be accounted for. Unless indicated otherwise, parts are parts by mole, molecular weight is average molecular weight, percent concentration (%) means the mass of the solute in grams divided by the volume of the solution in milliliters times 100% (e.g., 10% substance X means 0.1 gram of substance X per milliliter of solution), temperature is in degrees Centigrade, and pressure is at or near atmospheric pressure.
Example 1
Cell Lines
[0093] CHO-K1 derived host cell line was transfected with two plasmids encoding heavy and light chain of a human antibody. Both plasmids contain the hph gene conferring resistance to hygromycin B (Asselbergs and Pronk, 1992, Mol. Biol. Rep., 17(1):61-70). Cells were transfected using LIPOFECTAMIN reagent (Invitrogen cat.#18324020). Briefly, one day before transfection 3.5 million cells were plated on a 10 cm plate in complete F12 (Invitrogen cat.#11765) containing 10% fetal bovine serum (FBS) (Invitrogen cat.#10100). On the day of transfection the cells were washed once and medium was replaced with OPTIMEM from (Invitrogen cat.#31985). DNA/Lipofectamin complexes were prepared in OPTIMEM medium and then added to the cells. The medium was changed again to the complete F12 with 10% FBS 6 hours later. The stable integration of the plasmids was selected using hygromycin B selection agent at 400 μg/ml. Clonal antibody expressing cell lines were isolated using the FASTR technology (described in the U.S. Pat. No. 6,919,183, which is herein incorporated by reference).
[0094] The antibody expressing lines were then re-transfected with the EDEM2 encoding plasmid. EDEM2 plasmids contained either neomycin phosphotransferase (plasmid construct designated “p3”) or sh ble (plasmid “p7”) genes to confer resistance to either G418 or zeocin respectively. The same transfection method was used. Depending on the selectable marker, cells were selected with either G418 or zeocin at 400 μg/ml or 250 μg/ml, respectively. The clonal cell lines were then isolated using FASTR technology.
[0000]
TABLE 3
Cell Lines
Name
Enhancers
Constructs
Protein
C1
EDEM2 + XBP1
HC/LC = p1/p2
αAng2
C2
XBP1
EDEM2 = p3
XBP1 = p4
C3
EDEM2 + XBP1
HC/LC = p5/p6
αGDF8
C4
XBP1
EDEM2 = p7
C5
EDEM2
XBP1 = p4
C6
EDEM2 + XBP1
HC/LC = p8/p9
αAngPtl4
C7
XBP1
EDEM2 = p3
XBP1 = p4
Example 2
[0095] The antibody production was evaluated in a scaled-down 12-day fed batch process using shaker flasks. In this method the cells were seeded in a shaker flask at the density of 0.8 million cells per mL in the production medium (defined media with high amino acid). The culture was maintained for about 12 days, and was supplemented with three feeds as well as glucose. The viable cell density, and antibody titer were monitored throughout the batch.
[0096] To determine the effect of mEDEM2 on enhanced protein production, the production of proteins by CHO cell lines containing mEDEM2 and mXBP1 were compared to production by control cells that contained mXBP1, but not mEDEM2. Protein titers were higher in those cell lines expressing mEDEM2 versus those cell lines that did not express mEDEM2.
[0000]
TABLE 4
TITERS
Production rate
Titre g/L
Cell Line
Enhancers
(ρg/cell/day)
(% increase)
C1
EDEM2 + XBP1
39
8.1 (93)
C2
XBP1
39
4.2
C3
EDEM2 + XBP1
37
5.9 (55)
C8
XBP1
32
3.8
C6
EDEM2 + XBP1
94
5.3 (152)
C7
XBP1
52
2.1
C5
EDEM2
29
3.1 (343)
C9
—
9
0.7
Example 3
Integrated Cell Days
[0097] Integrated Cell Density (“ICD”) is a phrase used to describe the growth of the culture throughout the fed batch process. In the course of the 12-day production assay, we monitored viable cell density on days 0, 3, 5, 7, 10, and 12. This data was then plotted against time. ICD is the integral of viable cell density, calculated as the area under the cell density curve. EDEM2 transfected lines have higher ICD in a 12-day fed batch process (see Table 5).
[0000]
TABLE 5
INTEGRATED CELL DENSITIES
ICD 10 6 cell-day/mL
Cell Line
Enhancers
(% increase)
C1
EDEM2 + XBP1
205 (93)
C2
XBP1
106
C3
EDEM2 + XBP1
157 (34)
C4
XBP1
117
C6
EDEM2 + XBP1
56 (51)
C7
XBP1
37
C5
EDEM2
116 (59)
C9
—
73
Example 4
Anti-GDF8 Antibody Production
[0098] The effect of ectopic expression of EDEM2, XBP1, or both on the production of an anti-GDF8 antibody having a heavy chain sequence of SEQ ID NO: 19 and a light chain sequence of SEQ ID NO: 21 was examined. Individual cell-lines were examined for titer and integrated cell density and placed into “bins”, or ranges of values. Ectopic expression of EDEM2 significantly increased the number of cell lines that express antibody in the 5-6 g/L titer range. The combination of XBP1 and EDEM2 showed more than an additive effect toward the increase in high titer cell lines. The expression of EDEM2 in the antibody secreting cells also significantly increased the number of cell lines that attain a high ICD (see Table 6).
[0000]
TABLE 6
con-
Titre Bins (g/L)
ICD Bins (10 6 cell-day/mL)
struct
<1
1-3
3-5
5-6
30-50
50-100
100-200
E + X
0%
33.3%
44.4%
22.2%
11.1%
50%
38.9%
X
0%
37.5%
54%
8.3%
14.3%
85.7%
0%
E
0%
33%
60%
7%
0%
27%
73%
—
82%
18%
0%
0%
13%
67%
21%
Example 5
Productivity and Stability of EDEM2-Expressing Cells
[0099] The effect of ectopic expression of XBP1 or EDEM2 on the production of a monospecific antibody of interest (identified as clonal cell lines RGC91 or RGC92, respectively) was examined. Individual cell lines were examined for protein titer and integrated cell density, as well as stability.
[0100] Modified CHO K1 host cells stably expressing XBP1 (RGC91) or EDEM2 (RGC92) at a transcriptionally active locus (U.S. Pat. No. 8,389,239B2, issued Mar. 5, 2013) were transfected with a recombinant plasmid vector comprising the antibody gene of interest and a hygromycin resistance gene (hyg).
[0101] 400 μg/mL hygromycin was used for selection of transfected cells. Positive integrants expressing the antibody of interest (randomly integrated in the CHO genome), and also stably expressing either XBP1 or EDEM2, were confirmed and isolated by fluorescence-activated cell sorting (FACS) analysis. The isolated clones were expanded in suspension cultures in serum-free production medium. Clones were isolated from selected pools and were subjected to a 12 day fed batch productivity assay, and the protein titer of the antibody of interest was determined. Integrated cell density is calculated by measuring viable cell count on a given day in the production assay (counts are taken every 3 days and plotted on a curve against cell count).
[0102] As shown in FIG. 1A , the average protein titers for clones isolated from RGC91 and RGC92 was 4.2 and 5.2, respectively (for 24 representative antibody-expressing clones). Ectopic expression of EDEM2 increased the number of clones that attain antibody titer above 5 g/L ( FIG. 1A ) compared to XBP1-expressing clones. Clonal cell lines expressing EDEM2 isolated from the RGC92 host also maintained higher (25%-100% higher) integrated cell densities when compared to clones isolated from XBP1-expressing RGC91 host (see FIG. 1B ). EDEM2 clones established an ICD greater than 100 ( FIG. 1B ) in most clones tested. Clones isolated from EDEM2 expressing RGC92 host also resulted in significantly higher stability ( FIG. 2B ), as observed in flow cytometry-based autologous secretion trap (FASTR) scans (for reference, U.S. Pat. No. 6,919,183B2, issued Jul. 19, 2005) showing a homogenous producing population, in the representative sample of 24 clonal cell lines tested. Many of the clones isolated from XBP1 expressing RGC91 host appear to have a non-producing heterogeneous cell population ( FIG. 2A ). Without being bound to any one theory, EDEM2 facilitated the removal of misfolded proteins in the high expressing clones, thereby reducing stress in the cell during protein production and resulting in a more stable cell population. | The present invention relates to discovery of the ectopic expression of EDEM2 in a production cell to improve the yield of a useful multi-subunit protein. Thus, the present invention provides for production cell lines, such as the canonical mammalian biopharmaceutical production cell—the CHO cell, containing recombinant polynucleotides encoding EDEM2. Also disclosed is a production cell containing both an EDEM2-encoding polynucleotide as well an XBP1-encoding polynucleotide. Improved titers of antibodies produced by these cell lines are disclosed, as well as the improved cell densities attained by these cells in culture. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a cuff of a blood pressure monitor for measuring the blood pressure as being mounted on the body of a subject, and more particularly relates to a structure of the cuff of a wrist-mount blood pressure monitor used in a wrist-mount blood pressure monitor for measuring the blood pressure on the wrist.
[0003] 2. Description of the Related Art
[0004] Recently, importance of self-control of blood pressure has recognized, and the wrist-mount blood pressure monitor capable of measuring more easily than the brachial type is widely used at home as a household blood pressure monitor. A schematic configuration of a conventional wrist-mount blood pressure monitor 100 is explained by referring to FIG. 12 and FIG. 13. FIG. 12 is a general perspective view showing the appearance of the wrist-mount blood pressure monitor 100 , and FIG. 13 is a block diagram showing an internal structure of the wrist-mount blood pressure monitor 100 . Referring to both diagrams, the wrist-mount blood pressure monitor 100 comprises a main body 101 incorporating a control device for measuring the blood pressure, and a cuff 102 of a wrist-mount blood pressure monitor which the main body 101 is attached.
[0005] A display 103 and a start switch 104 are provided on the outer surface of the main body 101 , and a pressure sensor 105 , a pressurizing pump 106 , an exhaust valve 107 , and a CPU 108 for controlling these devices are provided in its inside.
[0006] The cuff 102 of wrist-mount blood pressure monitor comprises an air bag 109 for collecting the air sent out from the pressurizing pump 106 and oppressing an artery of the wrist, a band 110 having the air bag 109 disposed at its inner side for mounting on the wrist, and a fastener 111 for winding and fixing the band 110 on the wrist.
[0007] Measurement of blood pressure by using the wrist-mount blood pressure monitor 100 having such configuration is explained by referring to FIG. 14 to FIG. 16. In FIG. 14 to FIG. 16, for the sake of convenience, only the cuff 102 of the wrist-mount blood pressure monitor is shown, and the main body 101 is not shown. FIG. 14 is a schematic sectional view of the cuff 102 of the wrist-mount blood pressure monitor along the longitudinal direction before mounting on the wrist, and air is not supplied into the air bag 109 yet. FIG. 15 is a sectional diagram showing a deflated state of the cuff 102 of the wrist-mount blood pressure monitor mounted on the wrist 1 . FIG. 16 is a sectional view showing an inflated state of the cuff 102 of the wrist-mount blood pressure monitor mounted on the wrist 1 .
[0008] The cuff 102 of the wrist-mount blood pressure monitor shown in FIG. 14 is fixed by using the band 110 so that the air bag 109 comes to a position confronting the radial artery 5 and ulnar artery 7 of the wrist 1 . Herein, the principal constituents of the wrist 1 include, as shown in FIG. 15,the radius 2 positioned at the thumb side, the ulna 3 positioned as the little finger side, the deep flexor digital tendon 4 a and palmar long flexor tendon 4 b positioned near the radius 2 , the radial artery 5 , the superficial flexor digital tendon 6 a and ulnar carpal tendon 6 b positioned near the ulna 3 , and the ulnar artery 7 .
[0009] When the cuff 102 of the wrist-mount blood pressure monitor is completely mounted on the wrist 1 , by supplying air from the pressurizing pump 106 into the air bag 109 as shown in FIG. 16, the radial artery 5 or the ulnar artery 7 (or both) of the wrist 1 is oppressed, and the exhaust valve 107 is released, and in the process of discharging air from the air bag 109 , the pressure in the air bag 109 is measured by the blood pressure sensor 105 , and the blood pressure measurement data is obtained.
[0010] The wrist-mount blood pressure monitor is said to be inferior in precision to the brachial type blood pressure monitor. One of the causes is lack of oppression force on the artery of the wrist. Lack of oppression force on the artery means that the pressure of the vascular inner wall to be measure (hereinafter called vascular inner wall pressure) is smaller as compared with the air bag inner pressure. When the vascular inner wall pressure and air bag inner pressure are equal, by measuring the air bag inner pressure, an accurate vascular inner wall pressure is obtained, so that an accurate blood pressure can be measured.
[0011] However, when the oppression force is insufficient, the air bag inner pressure becomes higher than the vascular inner wall pressure, and the air bag inner pressure is directly measured as the blood pressure, so that a higher blood pressure than the actual pressure is measured. One of the causes of such lack of oppression force is lack of oppression width (hereinafter cuff width) in the wrist by the air bag.
[0012] The guideline of cuff width of brachial type blood pressure monitor is specified by AHA (American Heart Association), but there is no guideline for the cuff width of wrist-mount blood pressure monitor. Accordingly, the definition of cuff width of the brachial type blood pressure monitor (width of specific multiple of diameter of applicable brachial girth) is directly applied to the wrist. At the present, the cuff width of wrist-mount blood pressure monitor is set at about 50 to 60 mm. If the cuff width of the wrist-mount blood pressure monitor is determined according to this definition, lack of oppression force occurs. One of the causes is that the wrist contains many muscles and tendons not existing in the brachium, and the bones are present relatively near the cuticle, and the oppression of artery by the air bag is impeded.
[0013] As shown in a sectional view in FIG. 16, a sufficient air is supplied in the air bag 109 , and the air bag 109 is inflated toward the wrist 1 side. However, due to the presence of the radius 2 and palmar long flexor tendon 4 b , the inflation of the air bag 109 is impeded, and the radial artery 5 is not oppressed sufficiently, and also the inflation of the air bag 109 is impeded by the presence of the superficial flexor digital tendon 6 a and ulnar carpal tendon 6 b , and the ulnar artery 7 is not sufficiently oppressed.
[0014] If the oppression of artery by the air bag 109 is not impeded at all, as schematically shown in FIG. 17, a specified cuff width W 1 can be obtained by sufficiently inflating the air bag 109 , but in the presence of the radius 2 , palmar long flexor tendon 4 b , and others, as schematically shown in FIG. 18, inflation of the air bag 109 is impeded by the presence of the radius 2 , palmar long flexor tendon 4 b , and others, and hence the cuff width W 2 is insufficient.
[0015] It is hence a primary object of the invention to present a cuff of wrist-mount blood pressure monitor capable of oppressing the artery positioned at the wrist securely without having effects of muscle, tendon and bone existing in the wrist area.
SUMMARY OF THE INVENTION
[0016] The cuff of a wrist-mount blood pressure monitor according to the invention comprises an inflatable bag receiving a predetermined amount of a fluid for pressurizing an artery of the wrist, and mounting means for mounting the inflatable bag on the wrist, in which the inflatable bag includes a first inflatable portion, and a second inflatable portion disposed between the first inflatable portion and the wrist, being made of a material having a higher stretchability than the material of the first inflatable portion.
[0017] In this configuration, when a fluid is supplied into the inflatable bag, both the first inflatable portion and second inflatable portion are inflated by the supply of the fluid. Since the second inflatable portion is made of a material having a higher stretchability than the material of the first inflatable portion, a specified pressure to the wrist side is assured by inflation of the first inflatable portion. Moreover, the second inflatable portion is inflated in a state of tight contact with the wrist, the second inflatable portion flexibly intrudes into the tendons and bones, so that the second inflatable portion may intrude into the spaces between a tendon and a tendon, between a tendon and a bone, or between a bone and a bone.
[0018] Accordingly, regardless of the presence of muscle, tendon or bone in the wrist, it is possible to sufficiently apply a pressure to the artery of the wrist since the pressure from the first inflatable portion is applied to the wrist with which the second inflatable portion comes into contact. As a result, insufficient pressurizing force can be improved, so that it is possible to measure the blood pressure with good accuracy even in a wrist-mount blood pressure monitor.
[0019] Owing to these features, as mentioned above, by inflation of the first inflatable portion, a specified pressure to the wrist side is assured, and the second inflatable portion is inflated in a state of tight contact with the wrist, so that the second inflatable portion may flexible intrude into the muscles, tendons and bones.
[0020] Further preferably, the shape of the second inflatable portion at the wrist side is formed of extruding portions and dent portions. By the shape of extruding portions and dent portions, a higher expanding and contracting property may be obtained, and intrusion of the second inflatable portion into the muscles, tendons and tone when inflated can be realized more securely.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] [0021]FIG. 1 is a schematic view of a sectional structure of a cuff 10 of a wrist-mount blood pressure monitor along the longitudinal direction before mounting on the wrist in a preferred embodiment of the invention.
[0022] [0022]FIG. 2 is a sectional view showing the cuff 10 of a wrist-mount blood pressure monitor being mounted on the wrist 1 .
[0023] [0023]FIG. 3 is a sectional view showing a state of pressing the wrist 1 by the cuff 10 of a wrist-mount blood pressure monitor.
[0024] [0024]FIG. 4 is a schematic view showing the principle of oppression of the wrist by using the cuff 10 of a wrist-mount blood pressure monitor.
[0025] [0025]FIG. 5 is a sectional view showing a structure at the time of deflation of first air bag 14 B and second air bag 16 B in embodiment 1.
[0026] [0026]FIG. 6 is a sectional view showing a structure at the time of inflation of first air bag 14 B and second air bag 16 B in embodiment 1.
[0027] [0027]FIG. 7 is a sectional view showing a structure at the time of deflation of first air bag 14 C and second air bag 16 C in embodiment 2.
[0028] [0028]FIG. 8 is a sectional view showing a structure at the time of inflation of first air bag 14 C and second air bag 16 C in embodiment 2.
[0029] [0029]FIG. 9 is a general perspective view (a), a sectional arrow view of X-X (b), and a sectional view in inflated state (c), showing a first undulated shape at the wrist 1 side of the second air bag 16 C.
[0030] [0030]FIG. 10 is a general perspective view showing a second undulated shape at the wrist 1 side of the second air bag 16 C.
[0031] [0031]FIG. 11 is a sectional view when the cuff 10 of a wrist-mount blood pressure monitor is applied in a structure for oppressing only the vicinity of the radial pedicular process.
[0032] [0032]FIG. 12 is a general perspective view showing a structure of conventional wrist-mount blood pressure monitor 100 .
[0033] [0033]FIG. 13 is a block diagram showing an internal structure of conventional wrist-mount blood pressure monitor 100 .
[0034] [0034]FIG. 14 is a sectional structural view of cuff 102 of a wrist-mount blood pressure monitor along the longitudinal direction before mounting on the wrist.
[0035] [0035]FIG. 15 is a sectional view in deflated state showing a state of cuff 102 of a wrist-mount blood pressure monitor mounted on the wrist 1 .
[0036] [0036]FIG. 16 is a sectional view in inflated state showing a state of cuff 102 of a wrist-mount blood pressure monitor mounted on the wrist 1 .
[0037] [0037]FIG. 17 is a schematic diagram showing an ideal state of oppression of the wrist by using the cuff of a wrist-mount blood pressure monitor.
[0038] [0038]FIG. 18 is a schematic diagram showing problems of oppression of the wrist by using the cuff of a wrist-mount blood pressure monitor.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0039] Referring to the drawings, preferred embodiments of the invention of the cuff of a wrist-mount blood pressure monitor are explained. The basic structure of the wrist-mount blood pressure monitor using the cuff of wrist-mount blood pressure monitor in the embodiments is same as that of the conventional wrist-mount blood pressure monitor 100 explained in FIG. 12, and the detailed description is omitted, and only the features of the structure of the cuff of wrist-mount blood pressure monitor of the invention are explained below.
[0040] First, the structure of the cuff of wrist-mount blood pressure monitor based on the invention and its principle of oppressing the wrist are explained below while referring to FIG. 1 to FIG. 4. FIG. 1 is a schematic view of a sectional structure of a cuff 10 of a wrist-mount blood pressure monitor along the longitudinal direction before mounting on the wrist in a preferred embodiment of the invention, FIG. 2 is a sectional view showing the cuff 10 of a wrist-mount blood pressure monitor being mounted on the wrist 1 , FIG. 3 is a sectional view showing a state of pressing the wrist 1 by the cuff 10 of a wrist-mount blood pressure monitor, and FIG. 4 is a schematic view showing the principle of oppression of the wrist by using the cuff 10 of a wrist-mount blood pressure monitor.
[0041] (Configuration)
[0042] First, referring to FIG. 1, the configuration of the cuff of a wrist-mount blood pressure monitor is explained. This cuff 10 of a wrist-mount blood pressure monitor comprises a first air bag 14 A as a first inflatable portion used for collecting the air sent out from a pressurizing pump and oppressing an artery of the wrist, and a second air bag 16 A as a second inflatable portion disposed between the first air bag 14 A and the wrist, being made of a material of a higher stretchability than the material of the first air bag 14 A. A band 11 is mounting means for mounting the first air bag 14 A and second air bag 16 A on the wrist, and a fastener 15 is used for winding around and fixing the band 11 on the wrist. In FIG. 1, air is not supplied into the air bags yet.
[0043] (Principle of Oppression on Wrist)
[0044] Secondly, the principle of oppression on the wrist by using the cuff 10 of a wrist-mount blood pressure monitor is explained by referring to FIG. 2 to FIG. 4. Referring to FIG. 2, by using the band 11 , the first air bag 14 A and second air bag 16 A are fixed to the positions confronting the radial artery 5 and ulnar artery 7 of the wrist 1 . The constituents of the wrist 1 are same as explained in FIG. 15, and same reference numerals are given and detailed description is omitted.
[0045] Next, referring to FIG. 3, when air is supplied, the first air bag 14 A is inflated toward the wrist 1 side, and further the second air bag 16 A, when air is supplied, is inflated to intrude mainly into the tendons or bones of the wrist 1 .
[0046] Explaining in further detail, by inflation of the second air bag 16 A, the second air bag 16 A intrudes into the radius 2 and palmar long flexor tendon 4 b . As a result, the second air bag 16 A gets into the space between the radius 2 and palmar long flexor tendon 4 b , and the radial artery 5 is sufficiently oppressed by the second air bag 16 A. Also by inflation of the second air bag 16 A, the second air bag 16 A intrudes into the superficial flexor digital tendon 6 a and ulnar carpal tendon 6 b . As a result, the second air bag 16 A gets into the space between the superficial flexor digital tendon 6 a and ulnar carpal tendon 6 b , so that the ulnar artery 7 is sufficiently oppressed by the second air bag 16 A.
[0047] As shown in FIG. 4, when air is supplied into the first air bag 14 A and second air bag 16 A, both the first air bag 14 A and second air bag 16 A are inflated by supply of fluid, but since the second air bag 16 A is made of a material of a higher stretchability than the material of the first air bag 14 A, by inflation of the first air bag 14 A, a specified pressure to the wrist 1 side is maintained. In a state in tight contact with the wrist 1 , the second air bag 16 A is inflated, and the second air bag 16 A flexibly intrudes into the tendons or bones, so that the second air bag 16 A gets into the space between the radius 2 and palmar long flexor tendon 4 b , and hence the pressure from the first air bag 14 A is applied to the wrist 1 which is kept in contact with the second air bag 16 A regardless of the presence of the radius 2 and palmar long flexor tendon 4 b of the wrist 1 . Similarly, the second air bag 16 A gets into the space between the superficial flexor digital tendon 6 a and ulnar carpal tendon 6 b . As a result, a sufficient cuff width W 3 can be obtained.
[0048] From the viewpoint of intrusion of the air bags into the tendons and bones, the air bags may be made of stretchable materials only. However, in the case of using air bags made of stretchable materials only, sufficient pressure is not applied in the direction for oppressing the wrist, but the air bags are largely inflated in the lateral direction, and the wrist cannot be oppressed sufficiently. Therefore, as mentioned above, it is important to combine the first air bag 14 A as the first inflatable portion, and the second air bag 16 A as the second inflatable portion made of a material of higher stretchability than the first air bag 14 A.
[0049] (Embodiment 1)
[0050] A configuration of exemplary embodiment 1 on the basis of the above principle of oppression is explained by referring to FIG. 5 and FIG. 6. FIG. 5 shows only the air bags of the cuff 10 of wrist-mount blood pressure monitor in a deflated state before supply of air, and FIG. 6 shows an inflated state after supply of air.
[0051] As shown in FIG. 5, the structure comprises a first air bag 14 B as a first inflatable portion, and a second air bag 16 B as a second inflatable portion positioned between the first air bag 14 B and the wrist, being made of a material of a higher stretchability than the material of the first air bag 14 B. A specific material of the first air bag 14 B is vinyl chloride (a film thickness of about 0.3 mm). Other material usable for the first airbag 14 B includes EVA (vinyl acetate; a film thickness of about 0.3 mm), and urethane (a film thickness of about 0.3 mm).
[0052] To encourage inflation to the wrist side, a taper is formed of side walls 14 a , 14 b (accordion structure). When deflated, the thickness of the first air bag 14 B is about 1.2 mm.
[0053] Specific materials for the second air bag 16 B include thin films of silicone and latex, and the film thickness is about 0.3 mm. Other materials for the second air bag 16 B include silicone and latex.
[0054] In the first air bag 14 B and second air bag 16 B, air feed pipes 14 c , 16 c are provided, and a common air feed tube 17 is coupled to equalize the air pressure between the first air bag 14 B and second air bag 16 B.
[0055] In the configuration above, when air is fed into the first air bag 14 B and second air bag 16 B, as shown in FIG. 6, since a taper is formed in the first air bag 14 B, it is inflated mainly in a direction of oppressing the wrist. On the other hand, the second air bag 16 B is inflated in all directions. As a result, as mentioned above, the artery of the wrist can be oppressed sufficiently.
[0056] (Embodiment 2)
[0057] A configuration of exemplary embodiment 2 on the basis of the above principle of oppression is explained by referring to FIG. 7 and FIG. 8. FIG. 7 shows only the air bags in a state before supply of air, and FIG. 8 shows a state after supply of air.
[0058] As shown in FIG. 7, the structure comprises a first air bag 14 C as a first inflatable portion, and a second air bag 16 C as a second inflatable portion positioned between the first air bag 14 C and the wrist, being made of a material of a higher stretchability than the material of the first air bag 14 C. Specific materials and thickness of the first air bag 14 c are same as in embodiment 1. In structure, similarly, a taper is formed of side walls 14 a , 14 b for encouraging inflation to the wrist side. Specific materials for the second air bag 16 C are also same as in embodiment 1 , but the structural feature of this embodiment is that the shape of the second air bag 16 C at the wrist side is an undulated shape 18 .
[0059] By this undulated structure 18 , as shown in FIG. 8, when air is supplied into the first air bag 14 C and second air bag 16 C, a higher stretchability than in embodiment 1 is obtained at the wrist side of the second air bag 16 C, and when inflated, the second air bag 16 C can intrude more securely into the tendons or bones. Or if the required size of the second air bag 16 C in inflated state is same as in embodiment 1, in deflated state, the size of the second air bag 16 C is smaller than in embodiment 1, so that the size of the air bag can be reduced.
[0060] [0060]FIG. 9 and FIG. 10 perspective development views showing the specific shape of the undulated shape 18 at the wrist 1 side of the second air bag 16 C. FIG. 9 shows a first undulated shape 18 A, in which (a) is a general perspective view, (b) is a sectional arrow view of X-X of (a), and (c) is a sectional view in inflated state. FIG. 10 is a general perspective view showing a second undulated shape 18 B at the wrist 1 side of the second air bag 16 C.
[0061] The undulated shape 18 A in FIG. 9( a ) comprises extruding portions 18 a and dent portions 18 b disposed alternately like waves along the longitudinal direction (see sectional view in FIG. 9( b )), and in inflated state, as shown in FIG. 9( c ), all parts corresponding to the extruding portions 18 a and dent portions 18 b come to the outer side, so as to be inflated largely. The length of the extruding portions 18 a is about 30 mm, the width is about 7.5 mm, and the height is about 2 mm.
[0062] On the other hand, the undulated shape 18 B shown in FIG. 10 comprises block-shaped extruding portions 18 a disposed in a matrix, and dent portions 18 b disposed between the extruding portions 18 a like a lattice. The size of one extruding portion 18 a is about 7.5 mm×7.5 mm, and the height is about 2 mm. In the case of this undulated shape 18 B, too, same as in the undulated shape 18 A, when inflated, all parts corresponding to the extruding portions 18 a and dent portions 18 b come to the outer side, so as to be inflated largely.
[0063] In embodiments 1 and 2, the first air bags 14 A, 14 B, 14 C, and second air bags 16 A, 16 B, 16 C are provided in order to oppress both the radial artery 5 and ulnar artery 7 of the wrist, but a method of oppressing only the vicinity of the radial pedicular process is proposed by S. Mutsu et al. in “Analysis by finite element method about fitting position and size of cuff for local oppression in measurement of blood pressure by the wrist” (11th fall general meeting of Japan Society of ME). This paper, however shows or, teaches nothing about the technology of using first air bag and second air bag.
[0064] Therefore, the structure of these embodiments can be also applied in a structure for oppressing only the vicinity of the radial pedicular process. FIG. 11 shows the structure of the cuff 10 of a wrist-mount blood pressure monitor being applied for oppressing only the vicinity of the radial pedicular process. In this case, too, by inflation of the first air bag 14 A, a specified pressure to the wrist 1 side is assured, and the second air bag 16 A is inflated in a state of tight contact with the wrist 1 , and the second air bag 16 A intrudes flexibly into the tendons or bones, so that the second air bag 16 A gets into the space between the radius 2 and palmar long flexor tendon 4 b , so that the radial artery 5 can be sufficiently oppressed.
[0065] In the foregoing embodiments, the first air bag and second air bag are composed as independent air bags, but they may be made of a single air bag as far as the region of the first air bag is inflated mainly toward the wrist 1 side when air is supplied and the region of the second air bag is inflated to intrude mainly into the tendons or bones of the wrist 1 when air is supplied.
[0066] In the embodiments, air is used as the fluid, but not limited to air, but other gas having similar properties may be used (for example, oxygen, carbon dioxide, helium). Not limited to gas, water or other liquid may be also used. When liquid is used, an airtight structure must be employed in the fluid passage so as to avoid liquid leak.
[0067] Therefore, the present embodiments are illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that fall within metes and bounds of the claims, or equivalence of such metes and bounds thereof are therefore intended to be embraced by the claims.
[0068] According to the cuff of a wrist-mount blood pressure monitor according to the invention, the pressure from the first inflatable portion is applied to the wrist which is kept in contact with the second inflatable portion regardless of the presence of tendons and bones of the wrist, and the artery of the wrist can be oppressed sufficiently. As a result, the problem of lack of oppression force of the artery is eliminated, and the blood pressure can be measured precisely by using a wrist-mount blood pressure monitor. | A cuff of a wrist-mount blood pressure monitor capable of oppressing an artery of the wrist securely without having effects of muscle, tendon or bone existing in the wrist area is presented. This cuff 10 of a wrist-mount blood pressure monitor comprises a first air bag 14 A as a first inflatable portion, and a second air bag 16 A as a second inflatable region disposed between the first inflatable portion 14 A and the wrist, being made of a material of a higher stretchability than the material for the first air bag 14 A. | 0 |
CROSS REFERENCE
This application is a division of U.S. patent application Ser. No. 10/033,460filed on Dec. 28, 200 now abandoned, which is a continuation-in-part of U.S. patent application Ser. No. 09/811,119 filed Mar. 17, 2001 now U.S. Pat. No. 6,682,269which is a continuation-in-part of U.S. patent application Ser. No. 09/377,094 filed on Aug. 19, 1999, now U.S. Pat. No. 6,250,850.
FIELD OF THE INVENTION
This invention relates generally to retaining walls. More particularly, the present invention relates to manufactured blocks that are used to construct mortarless retaining walls.
BACKGROUND OF THE INVENTION
Retaining walls can be both functional and decorative and range from small gardening applications to large-scale construction. Such walls are typically used to maximize horizontal surface areas by providing lateral support between differing ground levels, and reduce the possibility of erosion and slumping. They may be constructed of a variety of materials and shapes. Some have been constructed of wood timbers, others of rock in a natural form (such as limestone). Still others have been constructed of manufactured aggregate or concrete blocks.
Constructing a fit and true retaining wall can be a more labor intensive and exacting endeavor than one would believe. In addition to laying a level first course, the builder must take pains to ensure that each subsequent course is level. Otherwise, an error made in positioning a block in a lower course may become magnified as successive courses are stacked thereabove and become readily apparent to the human eye. This is especially true of mortarless wall constructions because there is no way to effectively compensate for irregularities and discontinuities, as opposed to block and mortar construction.
Present mortarless wall building methods usually include laying a course of blocks, filling the space behind the course with fill material, packing the fill material, and carefully removing extraneous fill material from the top of each completed course prior to the addition of the next course. This fill material usually consists of small, stones or similar material and is preferred because it provides a path for moisture to follow and relieves water pressure that may build up behind a wall. It is also preferred because of its ability to reduce water borne material from seeping between the joints of the blocks due to inclement weather. The final step of removing the extraneous fill material is time consuming but necessary to ensure the next course of blocks lies flat in intimate contact on the lower course.
One particular problem the prior art has failed to overcome is developing a retaining wall block configured to minimize or prevent unintended discontinuities and irregularities caused by blocks being stacked on extraneous fill material, dirt, and debris that is often present on the upper surface of the lower course of blocks.
For example, some larger blocks incorporate through-holes that extend from their bottom surface to their top surfaces. These through-holes are intended to reduce the amount of material required to form the block, thereby reducing its cost and weight, and they also create space into which fill material may be introduced once a course is finished. At first blush it would appear that, because the presence of through-holes reduces the surface area of the top and bottom of the block, they would also serve to decrease the area of possible interference by small stones and debris between courses. However, the mere presence of through-holes ensures the chances that some of the fill material dumped therein will spill over onto the remaining upper surfaces. Thus, through-holes actually exacerbate, rather than alleviate the problem.
Smaller blocks, on the other hand, cannot easily incorporate through-holes without jeopardizing their structural integrity, and this inability of smaller blocks to accommodate through-holes creates other problems. Fabricating a solid block out of material such as concrete may often result in a block which may weigh as much as or more than a larger block that includes through-holes. And, working with such blocks may be more difficult than working with larger blocks with through-holes. That is, the absence of through-holes or interruptions in the side walls makes it difficult to grasp and lift these blocks. This becomes an important consideration in light of the number of blocks that must be lifted and set in place during the construction of even a relatively small retaining wall.
There is a need for a retaining wall block, which may accommodate debris between courses without adversely affecting the overall structure and aesthetics of the resulting wall. There is also a need for a small retaining wall block that has a reduced unit weight due to the absence of block material in an area that will not adversely affect the strength of the block or its appearance. And, there is a need for a small retaining wall block that is relatively easy to grasp and pick up off of a stack of similar blocks.
SUMMARY OF THE INVENTION
The present invention relates to a retaining wall block so shaped that when placed on top of a lower course of similar blocks, it lies flat despite the inevitable presence of dirt, small stones, and other debris. This feature alleviates the time-consuming step of meticulously cleaning the top of each course of blocks before the next course may be laid on top of it.
In order to achieve the tolerance of small stones and debris between courses, a portion of the bottom surface of the block of the present invention is non-planar, and preferably, concave. This non-planar portion significantly reduces the area for block-to-block contact between successive courses. It also functions to provide an area of clearance or a gap between adjacent blocks where debris can migrate without causing interference or instability between courses. The non-planar portion may be curved, preferably in the shape of a portion of a cylinder and extends from one side surface to the other. Alternatively, the non-planar portion could be shaped to form a portion of a sphere, oval, or any other shape that is capable of tolerating small stones and debris between courses. Preferably, the non-planar portion covers more than one half of the area of the bottom surface of the block.
In addition to the non-planar portion of the bottom surface, the present invention further comprises a plurality of grooves formed in the bottom surface and extending substantially transversely thereacross, preferably in parallel between the front and back surfaces. The grooves preferably are angled upwardly to form an inverted “V” shape when the block is given its intended orientation. The grooves allow spaces of increased clearance for larger stones. The grooves preferably comprise two opposed surfaces of a predetermined width and which are angled to form a “V” shape and meet to form an angle α. The angled walls of the grooves not only reduce the weight of the block and act as a splitting aid, but also act to direct larger stones into the grooves, thereby positioning them into an area of maximum clearance. Alternatively, the first and second surfaces may be joined by a third, curved or flat, surface juxtaposed between the first and second surfaces. Such a third surface would give the groove an inverted “U” shape. Preferably the grooves are integrally formed with the block and have a predetermined depth, which more or less follows the contour of the non-planar bottom surface.
The bottom surface further comprises one or more downward projections proximate the rear surface and having an abutting surface which contacts the rear surface of a lower course of blocks when the block is stacked thereon. It is envisioned that the abutting surface is either parallel to the rear surface of the block, or forms an angle β with the rear surface. These projections create an automatic and uniform setback among successive courses of blocks so that the resulting retaining wall is angled rearwardly. This also adds resistive strength to the wall against the natural forces exerted on the wall by the earth the wall is retaining, by tying successive courses of blocks to those course below them.
In an alternative embodiment, the block generally comprises a substantially continuous top surface, front and back surfaces extending from the top surface, multi-faceted side surfaces extending from the top surface and spanning from the front surface to perpendicularly intersect the back surface, and a bottom surface having a predetermined surface area that is integral with the front and side surfaces. An upwardly extending gutter is formed into the bottom surface of the block and is spaced away from the rear surface of the block a predetermined distance. The gutter formed into the bottom surface of the block preferably has a forward edge that has a minimal surface area that acts to support a rear portion of the block upon a lower course of blocks.
In order to further lighten a block constructed according this embodiment, the multifaceted side surfaces of the blocks include an inwardly inset sidewall portion that perpendicularly intersects the rear surface of the block. The multifaceted side surfaces of the block may further comprise a shoulder formed between the aforementioned sidewalls and a forward portion of the multifaceted side surfaces wherein the shoulder and the forward portion of the multifaceted side wall intersect at an obtuse angle.
Preferably, the downward projection has a generally trapezoidal cross-sectional shape and is spaced away from the rear surface of the block a predetermined distance. In addition, the abutting surface of the downward projection is preferably contiguous with a rear face of the gutter.
The front surface of the aforementioned preferred embodiments may be configured to have a plurality of planar segments or may be curvilinear. However, it is understood that other configurations are possible. For example, the front surface may be planar, angular, or prismatic and have a wide variety of finishes.
The present invention advantageously provides a block for use in building a retaining wall that produces a level course of blocks, despite the presence of a small amount of debris on the lower course of blocks.
The present invention is also advantageous in that it provides a relatively small block with material removed from strategic locations to provide a block which is lighter than it would have been had it been solid, yet the removal of material has not adversely affected the strength of the block, nor the appearance of the resulting wall.
The present invention advantageously provides a block that has areas for a person building a retaining wall to grasp the block when lifting the block off of a stack of such blocks and placing the block on a lower course of blocks in the wall being constructed.
These and other objectives and advantages of the invention will appear more fully from the following description, made in conjunction with the accompanying drawings wherein like reference characters refer to the same or similar parts throughout the several views.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a block of the present invention, looking up at the bottom to reveal the details of the bottom surface;
FIG. 2 is a cross sectional view of the block of the present invention taken along lines 2 — 2 of FIG. 1 ;
FIG. 3 is a cross sectional view of the block of the present invention taken along lines 3 — 3 of FIG. 1 and shown with other blocks in phantom, stacked, as in a retaining wall;
FIG. 4 is a bottom plan view of the block of FIG. 1 ;
FIG. 5 is a perspective view of the block shown in FIG. 1 in a stacked relationship with other blocks, as in a wall, and showing debris resting on a lower course of blocks and accommodated for by the concave area of the bottom surface of the block of the present invention;
FIG. 6 is a perspective view of an alternative embodiment of the present invention, looking up at the bottom to show the detail of the bottom surface;
FIG. 7 is a sectional elevational view taken along lines 7 — 7 of FIG. 6 ;
FIG. 8 is an end elevational view of a block of the embodiment shown in FIG. 6 , in stacked relation, as in a wall, with other blocks shown in phantom;
FIG. 9 is a bottom plan view of a block of the embodiment shown in FIG. 6 ;
FIG. 10 is a bottom plan view of a block of the present invention;
FIG. 11 is a cross-sectional view of the block of FIG. 10 taken along cutting lines 11 — 11 in FIG. 10 ;
FIG. 12 is a cross-sectional view of the block of FIG. 10 taken along cutting lines 12 — 12 in FIG. 10 ;
FIG. 13 is a top plan view of the block of FIG. 10 ;
FIG. 14 is a front elevational view of the block of FIG. 10 ;
FIG. 15 is a side elevational view of a first side of the block of FIG. 10 ;
FIG. 16 is a side elevation view of a second side of the block of FIG. 10 ;
FIG. 17 is a perspective view of an alternative embodiment of the block shown in FIG. 1 in a stacked relationship with other blocks, as in a wall, and showing debris resting on a lower course of blocks and accommodated for by the non-planar area of the bottom surface of the block of the present invention and also showing a curved front surface;
FIG. 18 is a perspective view of an alternative embodiment of the present invention, looking up at the bottom to show the detail of the bottom surface;
FIG. 19 is a bottom plan view of a block of the embodiment shown in FIG. 18 ;
FIG. 20 is a bottom plan view of an alternative embodiment of the block of the present invention in which the front surface is curved;
FIG. 21 is a top plan view of the block of FIG. 20 ;
FIG. 22 is a front elevation view of the block of FIG. 20 ; and,
FIG. 23 is a side elevation view of a series of blocks of FIG. 20 as they would appear in a stacked relation.
DETAILED DESCRIPTION
Referring now to FIG. 1 , there is shown a retaining wall block 10 having a front surface 12 , side surfaces 14 a and 14 b extending rearwardly from front surface 12 and integral with rear surface 16 . Top surface 18 is generally planar and continuous across its extents. Top surface 18 extends from side surface 14 a to side surface 14 b, and from front surface 12 to rear surface 16 . Preferably, top surface 18 is generally perpendicular to side surfaces 14 a and 14 b, and also to front surface 12 and rear surface 16 .
In the embodiment shown in FIGS. 1–9 , front surface 12 comprises three parts, 12 a, 12 b, and 12 c. Part 12 c is generally parallel to rear surface 16 and lies between parts 12 a and 12 b. Parts 12 a and 12 b are angled such that they extend from part 12 c and diverge rearwardly to meet side surfaces 14 a and 14 b, respectively. Parts 12 a, 12 b, and 12 c are shown as split faces as opposed to formed or finished faces. Creating a face with a rock splitter results in an irregular, more natural appearing surface. Also shown in the Figures is a rear surface 16 that has a smaller width than front surface 12 such that side surface 14 a and 14 b must converge rearwardly in order to be integral with rear surface 16 . This shape allows the construction of straight, concave, convex, or serpentine walls without interrupting the relatively uniform appearance created by the front surfaces 12 of a plurality of blocks 10 forming a wall.
Bottom surface 20 extends from front surface 12 to rear surface 16 and from side surface 14 a to side surface 14 b. Bottom surface 20 includes a non-planar portion 22 . Non-planar portion 22 is depicted in FIGS. 1 , 3 , and 4 as a relatively cylindrical indentation in bottom surface 20 , extending from side surface 14 a to side surface 14 b. The non-planar portion 22 does not intersect the front surface 12 , and preferably does not extend substantially forward of the intersection where side surfaces 14 a and 14 b meet parts 12 a and 12 b of front surface 12 . This ensures that non-planar portion 22 is substantially hidden from view in a completed wall, regardless of whether the wall is straight, concave, convex, or serpentine.
Allowing non-planar portion 22 to extend from side surface 14 a to side surface 14 b creates a gap 24 between the bottom surface 20 and the upper surface of a lower course of blocks when block 10 is placed thereon. This gap 24 may be used for ease in picking the block up and setting the block down. Also, as shown in FIGS. 1 , 3 and 4 , non-planar portion 22 extends rearwardly but ends forward of downward projection 34 , which is described in more detail below. Ending the non-planar portion 22 forward of downward projection 34 provides another flat surface for block-to-block contact to assist in the leveling and stabilization of block 10 on a lower course of blocks.
Alternatively, it is envisioned that non-planar portion 22 be an indentation of any shape, such as the generally ovate or spherical shape of the embodiment shown in FIGS. 6–9 . Preferably, non-planar portion 22 is large enough to occupy at least 30 percent, more preferably on the order of 50 to 75 percent, of the surface area of bottom surface 20 .
In one embodiment, bottom surface 20 also includes at least one, preferably a plurality of, grooves 28 . As shown in FIG. 2 , grooves 28 are preferably “V”-shaped and extend from the bottom surface into the block toward top surface 18 . In the embodiment depicted in FIGS. 1 and 2 , grooves 28 are spaced generally equidistant from each other and oriented such that they extend from front to back generally across the non-planar portion 22 . It is envisioned that grooves 28 could be located generally anywhere across bottom surface 20 . It is preferred, however, that grooves 28 do not intersect front surface 12 so that grooves 28 remain hidden from view when block 10 is part of a completed wall.
Grooves 28 having the preferred “V” shape generally comprise at least a first surface 30 and a second surface 32 . First surface 30 extends from bottom surface 20 and is integral with second surface 32 . Second surface 32 extends from first surface 30 to bottom surface 20 thereby forming an angle α between first surface 30 and second surface 32 as seen in FIGS. 2 and 7 . Angle α is preferably less than 180 degrees. Alternatively, first surface 30 and second surface 32 could be joined by a third surface (not shown in the Figures), which extends along the length of the groove and is juxtaposed between the first and second surfaces. This third surface could be curved, thereby forming a “U” shaped groove, or the third surface could be flat, thereby forming a rectangular groove. However, a “V” shaped groove generally eases manufacturing.
As shown in all Figures, bottom surface 20 also includes at least one downward projection 34 . Downward projection 34 may extend across bottom surface 20 , adjacent rear surface 16 as shown in FIGS. 1 , 2 , and 4 . Alternatively, projection 34 may be broken into more than one projection 34 as shown in FIGS. 6 , 7 and 9 . Projection 34 has an abutting surface 36 which is used to abut against the rear surface 16 of a lower course of blocks, thereby forming a setback between successive courses of blocks. This setback adds strength and stability to the resulting wall.
Abutting surface 36 may be substantially parallel to rear surface 16 . Alternatively, for ease of manufacture, abutting surface 36 may angle rearwardly forming a relatively small angle β with rear surface 16 as shown in FIG. 3 . Angle β is preferably less than 45 degrees, more preferably less than 30 degrees. A smaller angle β provides more resistance to horizontal block slippage due to external forces against the back of the resulting wall.
Referring now to FIGS. 10–16 , there is shown a preferred embodiment of a retaining wall block 50 having a front surface 52 , side surfaces 54 a and 54 b extending rearwardly from front surface 52 toward rear surface 56 . Top surface 58 is generally planar and continuous across its extents. Top surface 58 extends from side surface 54 a to side surface 54 b, and from front surface 52 to rear surface 56 . Preferably, top surface 58 is generally perpendicular to side surfaces 54 a and 54 b, and also to front surface 52 and rear surface 56 .
In the embodiment shown in FIGS. 10–16 , front surface 52 comprises three parts, 52 a, 52 b, and 52 c. In general, these parts will referred to as the front surface parts or as the face of the block 50 . Part 52 c is generally parallel to rear surface 56 and lies between parts 52 a and 52 b. Parts 52 a and 52 b are angled such that they extend from part 52 c and diverge rearwardly to meet side surfaces 54 a and 54 b, respectively. Parts 52 a, 52 b, and 52 c are in FIGS. 10–16 shown as formed or smooth faces as opposed to split faces. Block 50 may preferably be formed by splitting as described above in conjunction with FIGS. 1–9 . Creating a face with a rock splitter results in an irregular, more natural appearing surface. As can be seen in the Figures, rear surface 56 has a smaller width than front surface 52 . Side surfaces 54 a and 54 b converge rearwardly toward the rear surface 56 at obtuse angle to the rear surface 56 . This shape allows the construction of straight, concave, convex, or serpentine walls without interrupting the relatively uniform appearance created by the front surfaces 52 of a plurality of blocks 10 forming a wall.
Block 50 has a heel portion 70 that comprises the rear surface 56 , a projection 72 , and a gutter 74 . As can be seen most clearly in FIGS. 10 and 13 , sides 54 a and 54 b incorporate shoulders 76 a and 76 b, respectively. Shoulders 76 may also be seen as a forward boundary of the heel portion 70 of the block 50 . Note that shoulders 76 form an obtuse angle with respect to sides 54 . Heel portion side walls 78 a and 78 b extend rearwardly from respective shoulders 76 a and 76 b and intersect with rear surface 56 of block 50 . Heel portion side walls 78 a and 78 b are preferably formed perpendicular to shoulders 76 a and 76 b and to rear surface 56 of block 50 . The resulting sides 54 comprise multiple facets and provide a number of benefits. Formation of side walls 78 a and 78 b as illustrated in the FIGS results in a lighter block 50 as the block 50 will have a smaller volume. As a corollary benefit, less concrete material is used in the formation of block 50 where side walls 78 a and 78 b are formed as indicated.
Bottom surface 60 extends from front surface 52 to gutter 74 and from side surface 54 a to side surface 54 b. Bottom surface 60 includes a non-planar portion 62 . Non-planar portion 62 is depicted in FIGS. 11 , 12 , 15 , and 16 as a relatively cylindrical indentation in bottom surface 60 , extending from side surface 54 a to side surface 54 b. Preferably, non-planar portion 62 does not extend substantially forward of where side surfaces 54 a and 54 b intersect parts 52 a and 52 b of front surface 52 . In this way non-planar portion 62 will be substantially hidden from view in a completed wall, regardless of whether the wall is straight, concave, convex, or serpentine.
Allowing non-planar portion 62 to extend from side surface 54 a to side surface 54 b creates a gap 64 between the bottom surface 60 and the upper surface of a lower course of blocks when block 50 is placed thereon. This gap 64 may be used for ease in picking the block 50 up and setting the block down. As can be seen in FIGS. 11 , 12 , 15 , and 16 , gap 64 extends all the way to the edge 75 of gutter 74 . Because gap 64 extends all the way to edge 75 of gutter 74 , a block 50 in an upper course of blocks will rest upon a block 50 in a lower course of blocks upon that portion of bottom surface 60 that extends between the front face parts 52 a, 52 b, and 52 c and the forward edge 63 of the non-planar portion 62 and the edge 75 of gutter 74 . As can be appreciated, the rear of the block 50 is supported only on edge 75 and not on a planar surface, i.e. edge 75 , while having any number of curvilinear and/or rectilinear shapes, has a small surface area with respect to the remainder of bottom surface 60 . This affords the benefits of increased friction between two courses of blocks 50 and prevents the entrapment of sand, gravel, or bits of concrete between the upper surface 58 of a lower course of blocks and the bottom surface 60 of an upper course of blocks.
Gutter 74 extends upwardly from edge 75 into the body of block 50 toward the top surface 58 . Gutter 76 extends laterally between heel portion side walls 78 a and 78 b and has a generally “U” shaped cross-sectional area. Note that the exact cross-sectional shape of the gutter 76 may vary. However it is important to form the gutter 74 without sharp-edged surfaces. Therefore, the cross-sectional shape of the gutter 74 will be gently curved within the constraints of its position and size. Such a shape avoids the formation of unwanted stress concentration points that might facilitate the fracture of the block.
The rear face of the gutter 74 extends downwardly, away from the top surface of block 50 and beyond edge 75 to form an abutting surface 80 of projection 72 . Projection 72 and its abutting surface 80 function in the same manner as projection 34 and its abutting surface 36 , described above. That is, projection 72 acts to rearwardly offset each course of blocks 50 from the lower course upon which the upper course of blocks 50 rest. Projection 72 is preferably offset forwardly from the rear surface 56 . As can be seen in the Figures, rear face 82 of projection 72 is moved forward of the rear surface 56 of the block 50 . Additionally, it is preferred to cant the rear face 82 of projection 72 forwardly so that the projection has a generally trapezoidal cross-sectional shape with radiused edges. While this trapezoidal shape is not the only shape that may be used, it does afford additional durability to the projection 72 in that the lack of sharp edges prevents chipping and fracture of the projection 72 . The trapezoidal shape of the abutting surface 80 of the projection 72 aids in the rapid construction of walls by preventing the entrapment of sand, gravel, or pieces of concrete between the abutting surface 80 of the projection 72 of a block 50 in an upper course and the rear surface 56 a block 50 in a lower course.
The formation of a heel structure 70 such as that illustrated in FIGS. 10–16 has the additional benefit of strengthening the projection 72 by forcing more of the concrete from which the blocks 50 are formed into the area of the mold that forms the projection 72 . Projection 72 of block 50 therefore has fewer voids, is more dense and is consequently stronger.
In the preferred embodiment, bottom surface 60 also includes at least one, and preferably a plurality of, grooves 86 that are similar in shape and disposition to the grooves 28 described above in conjunction with FIGS. 1 and 2 . Grooves 86 preferably have the “V”-shape as described above. While the grooves 86 may be located generally anywhere across the bottom surface 60 , it is preferred to locate the grooves substantially within the curved portion 62 of the bottom surface 60 . As seen in FIG. 10 , grooves 68 may extend from front to back from a position on surface 60 somewhat forward of the point where front surfaces 52 a and 52 b interest side surfaces 54 a and 54 b, respectively, to a position just forward of edge 75 of gutter 74 . Care must be taken to space the grooves 86 away from edge 75 sufficiently to avoid weakening edge 75 . Grooves 86 not only result in a lighter block 50 , but also realize a cost savings in the use of less concrete to form the blocks 50 . Additionally, grooves 86 may aid installers in the field by providing a fracture line along with the block 50 may be broken to fill a gap in wall made from blocks 50 .
Referring now to FIG. 17 , block 110 includes a front surface 112 that comprises an outwardly curved, or curvilinear surface that is free from vertices that extend substantially from the top surface to the bottom surface, as opposed to a block having a front surface with vertices formed by facets, as depicted in FIG. 13 , for example. Although the front surface 112 is depicted as having a roughened texture that approximates a split-face look, it will be appreciated that other textures are possible. Also shown in the Figure is a rear surface 116 which has a smaller width than front surface 112 such that side surface 114 a and 114 b converge rearwardly in order to be integral with rear surface 116 . This shape allows the construction of straight, concave, convex, or serpentine walls without interrupting the relatively uniform appearance created by the front surfaces 112 of a plurality of blocks 110 forming a wall. As will be appreciated, the curvature of the front surface 112 of the block 110 may be configured so that the front surfaces of a plurality of blocks may also form closed, substantially cylindrical structures.
Although not depicted, the bottom surface of the block of this embodiment is identical to the bottom surface depicted in FIGS. 1 and 4 . Thus, the bottom surface extends from front surface to rear surface 116 and from side surface 114 a to side surface 114 b. Bottom surface includes a non-planar portion with a plurality of upwardly extending grooves (not shown). Non-planar portion is similar to the non-planar portion 22 depicted in FIGS. 1 , 3 and 4 , in that it is relatively cylindrical and extends from side surface 14 a to side surface 14 b. As with the non-planar portion 22 of FIGS. 1 , 3 , and 4 , the non-planar portion of this embodiment does not extend substantially forward of the points where side surfaces 114 a and 114 b intersect with the front surface 112 . This enables the non-planar portion to be substantially hidden from view in a completed wall, regardless of whether the wall is straight, concave, convex, or serpentine. Similarly, extending the non-planar portion from side surface 114 a to side surface 114 b creates a gap 124 between the bottom surface and the upper surface of a lower course of blocks that may also be used to facilitate manipulation of the block. Also, as shown in the Figure, non-planar portion 122 extends rearwardly towards downward projection 134 , but stops short a predetermined distance therebefore.
Referring now to FIGS. 18 and 19 , another embodiment shows a block 110 that includes a front surface 112 that comprises an outwardly curved, or curvilinear surface, which is free from vertices that extend substantially from the top surface to the bottom surface. The front surface 112 of this embodiment is also depicted as having a roughened texture that approximates a split-face look, but it is understood that other textures are possible. As with the embodiment as depicted in FIGS. 6–9 , the block of this embodiment includes a non-planar portion 122 that is substantially concave or ovate in shape, and a plurality of upwardly extending “V” shaped grooves 128 having convergent surfaces 130 , 132 .
Referring now to FIG. 20 , another embodiment shows also shows a block 150 that includes a front surface 152 that comprises an outwardly curved or curvilinear surface, which is free from vertices that extend substantially from the top surface to the bottom surface, as opposed to a block having a front surface with vertices formed by facets, as depicted in FIG. 13 , for example. Retaining wall block 150 also includes side surfaces 154 a and 154 b that extend rearwardly from front surface 152 toward rear surface 156 . Bottom surface 160 extends from front surface 152 to a gutter 174 and from side surface 154 a to side surface 154 b. Bottom surface 160 includes a non-planar portion 162 that is a relatively cylindrical indentation in bottom surface 160 , extending from side surface 154 a to side surface 154 b (See also, FIG. 23 ). The non-planar portion 162 is arranged so that it stops short of the front surface 152 , and preferably does not extend substantially forward of the points of intersection where side surfaces 154 a and 154 b meet the front surface 152 . This ensures that non-planar portion 162 is substantially hidden from view in a completed wall, regardless of whether the wall is straight, concave, convex, or serpentine.
A gap 164 , formed by the non-planar portion 162 , extends all the way from a forward edge 163 to the edge 175 of gutter 174 . Thus, a block 150 in an upper course of blocks will rest upon a block 150 in a lower course of blocks upon that portion of bottom surface 160 that extends between the front surface 152 and the forward edge 163 of the non-planar portion 162 , and the edge 175 of gutter 174 .
In this embodiment, bottom surface 160 also includes at least one, and preferably a plurality of, grooves 186 that are similar in shape and disposition to the grooves 28 described above in conjunction with FIGS. 1 and 2 , and as depicted in FIGS. 10 , 11 , and 12 . Grooves 186 preferably have the “V”-shape as described above. While the grooves 186 may be located generally anywhere across the bottom surface 160 , it is preferred to locate the grooves substantially within the curved portion 162 of the bottom surface 160 . As seen in FIG. 20 , grooves 168 may extend substantially from front to back from a position on surface 160 somewhat forward of the point where front surface 152 interests side surfaces 154 a and 154 b, respectively, to a position just forward of edge 175 of gutter 174 . Grooves 186 not only result in a lighter block 150 , but also realize a cost savings in the use of less concrete to form the blocks 150 . Additionally, grooves 186 may aid installers in the field by providing a fracture line along with the block 150 may be broken to fill a gap in wall made from blocks 150 .
Block 150 also has a heel portion 170 that comprises the rear surface 182 , a projection 172 and a gutter 174 . As can be seen more clearly in FIG. 21 , sides 154 a and 154 b incorporate shoulders 176 a and 176 b, respectively. Shoulders 176 may also be seen as a forward boundary of the heel portion 170 of the block 150 . Note that shoulders 176 form an obtuse angle with respect to sides 154 . Heel portion side walls 178 a and 178 b extend rearwardly from respective shoulders 176 a and 176 b and intersect with rear surface 156 of block 150 . Heel portion side walls 178 a and 178 b are preferably formed perpendicular to shoulders 176 a and 176 b and to rear surface 156 of block 150 . The resulting sides 154 comprise multiple facets and provide a number of benefits. Formation of side walls 178 a and 178 b as illustrated in the Figures results in a lighter block 150 as the block 150 will have a smaller volume.
Referring now to FIG. 21 , top surface 158 is generally planar and continuous across its extents. Top surface 158 extends from side surface 154 a to side surface 154 b, and from front surface 152 to rear surface 156 . Preferably, top surface 158 is generally perpendicular to side surfaces 154 a and 154 b, and also to front surface 152 and rear surface 156 . As can be seen in the Figures, rear surface 156 has a smaller width than front surface 152 . Side surfaces 154 a and 154 b converge rearwardly toward the rear surface 156 at obtuse angle to the rear surface 156
Referring now to FIG. 22 , the front surface 152 comprises a curvilinear surface that may be curved outwardly. This curvature enables blocks 152 to form wall structures that are substantially cylindrical. Although a relatively shallow arc that extends between the sides 154 a, 154 b is depicted, it will be appreciated that front surface 152 may be formed in different arcs, for example, a hemispherical arc. Moreover, the arced front surface 152 may be oriented so that it extends between the top and bottom surfaces 158 , 160 , or comprises a series of curvilinear surfaces in a scallop-like configuration.
Referring now to FIG. 23 , gap 164 between adjacent courses of blocks 150 can be more easily seen. As with the previous embodiments, gap 164 may be used to facilitate manipulation of blocks 150 . As can be appreciated, the rear of the block 150 is supported only on edge 175 and not on a planar surface. This minimizes the surface area supporting the rear of the block 150 and reduces the effects of extraneous material such as rocks, sand, or bits of concrete that may be present on the upper surface 158 of a lower course of blocks.
Gutter 174 has a generally “U” shaped cross-sectional area that extends upwardly from edge 175 into the body of block 150 and laterally between heel portion side walls 178 a and 178 b. As will be appreciated, the exact cross-sectional shape of the gutter 176 may vary. The rear face of the gutter 174 extends downwardly, away from the top surface of block 150 and beyond edge 175 to form an abutting surface 180 of projection 172 . Projection 172 and its abutting surface 180 functions in the same manner as projection 34 and its abutting surface 36 , described above. Projection 172 is preferably offset forwardly from the rear surface 156 . As can be seen in the Figures, rear face 182 of projection 172 is moved forward of the rear surface 156 of the block 150 so that the projection 172 is generally intermediate or interposed between the rear surface 156 and the rear edge 175 of the non-planar portion 162 . The positioning of the projection 172 away from the rear surface has an advantage in that it is less likely to be chipped and fractured while the block is being manipulated and positioned. In other words, it is in a location that offers greater protection. Note that the abutting surface 180 and the rear face 182 of projection 172 are canted towards each other so that the projection 172 has a generally trapezoidal cross-sectional shape. The trapezoidal shape of the projection 172 aids in the rapid construction of walls by preventing the entrapment of sand, gravel, or pieces of concrete between the abutting surface 180 of a block 150 in an upper course and the rear surface 156 a block 150 in a lower course.
The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims. | A block for use in constructing a multiple course retaining wall. The block has a substantially planar top surface, a front surface, wherein said front surface is of a substantially curvilinear shape, a rear surface, opposed side surfaces, and a bottom surface. The bottom surface has a predetermined area and a non-planar portion, with the non-planar portion comprising a continuous area making up at least one-quarter of the bottom surface and creating a cavity between the bottom surface of the block and a top surface of a lower course of blocks when the block is placed on the top surface of the lower course of blocks. The cavity allows dirt and other foreign matter to exist between successive courses of blocks without creating instability between the block and the lower course of blocks. | 4 |
The invention disclosed below relates to a protective collar used to enhance the protection given by a crash helmet to the head and neck of a wearer, when engaged in such activities as motor racing.
It is nowadays a virtually universal practice—and often a requirement—for participants in such sports as motor racing (including open wheel, speedway, dragster-type, sports cars and sedan cars and even go karts) and motor boat racing to wear crash helmets for protection in the event of an accident. Such helmets help to protect the head and upper neck of their wearer, and are considered to be of proven benefit. From early bowl-shaped helmets which simply covered the top of the head, to helmets extending downwards approximately to the wearer's jawline at the sides and partly down the rear of the head to cover the upper neck, there have evolved “full face” helmets which also have a section extending around the wearer's chin, the face being protected by a transparent visor. Such helmets are also widely worn by motorcyclists for ordinary use on public roads.
In sporting applications particularly, other protective equipment has been developed for wearing by participants, such as protective suits, boots and the like. Vehicles other than motorcycles have been fitted with reinforced structures, rapidly-deployable airbags and restraining harnesses for further protection.
Yet collisions and other types of accidents occur and injuries incurred in them may still be very severe, and these include injuries to the upper neck and head areas of persons wearing full-face crash helmets. One measure which has been taken to give additional protection to such persons is the use of a collar of resilient material worn between the upper body and the base of a crash helmet. Some such collars are split at the front so that they can be more easily placed around the neck and have fastenings at the front so that once around the neck they will remain there. These can limit to some degree the movement of a helmet (and the head inside it) during an impact or rapid deceleration. They can, however, be uncomfortable and unduly restrictive to head movement in ordinary situations, as when a wearer wishes to look quickly from side to side while driving in a race.
It should be understood that the combination of a head and a helmet is of considerable weight and if it is allowed to move violently in an impact, rapid deceleration or other event, large stresses can be placed on the upper spine, potentially leading to excessive extension and/or bending resulting in injury such as spine fractures, “whiplash”, other soft tissue injuries and the like.
A related development has been the provision of collars which themselves employ rapidly-deployable airbags which inflate when an impact is sensed, the inflated bag purportedly protecting the upper body and steadying the helmet against excessively violent movement. Such devices are expensive and comparatively complex and appear not to have become popular.
The present invention has been developed to provide protection against the effects of excessively violent movement of the head and neck of a full-face crash helmet wearer more effectively than the simple resilient collars mentioned above and without the complexity, expense and possible unreliability of airbag-type devices. A particular objective has been to improve the protection of a full-face crash helmet wearer in the event of a side impact. An additional objective has been to give such protection while limiting as little as possible the freedom of movement of the wearer.
SUMMARY OF THE INVENTION
According to the invention there is provided a protective collar for use with full-face crash helmets,
including a collar member at least partially formed from a resilient material which in use extends peripherally entirely around a user's neck
said collar member having a recess in which a lower part of a full-face crash helmet is receivable and securable and helmet retaining means for retaining said crash helmet within said recess,
said recess having an upwardly facing bottom surface which in use abuts said lower part of said helmet and a peripherally extending wall surface which extends upwardly from said surface to a top surface of said collar, faces into said recess and in use of said collar closely fits against said lower part of said helmet around the periphery thereof,
wherein in use of said collar said user's neck passes through an opening in said collar member, said opening having an upper end within said recess and inwardly facing surfaces conforming closely to at least both sides and the back of said user's neck.
The feature of close fitting of the protective collar in particular, in combination with the other features mentioned above, gives advantages in use which will be further explained below. Preferably, the periphery of said opening said collar has a thickness greater than or equal to the average depth of said recess. This thickness, below said recess in a direction perpendicular to said bottom surface, may be substantially constant. A front part of said opening in use of said collar may extend in a forward direction clear of said user's neck. This is for comfort—for example to clear a wearer's “Adam's apple”—and to provide an air inlet to the helmet interior.
Preferably, the collar member has a split at a peripheral location so that parts of said collar on opposing sides of said split are separable by a user to enable said collar to be fitted around said lower part of said helmet. This facilitates putting the collar on after the helmet is secured to the wearer's head in conventional fashion. It is then desirable that the collar include closure means for holding said parts on opposing sides of said split in defined positions against each other after fitting of said collar around said helmet.
Loop-pile fasteners of the type known by the trade name “Velcro” are particularly suitable for the closure means and may be applied in several ways. Thus, the closure means may include a strap secured to said collar member and having secured at one end thereof a first half of a loop-pile fastener combination such as “Velcro”, a second half of said fastener combination being secured to said collar member and located so that when said fastener halves are mated with each other said split is held closed. Preferably, this strap is secured to an external surface of said collar member. It may provide significant reinforcement or stiffening for the collar member.
Alternatively, the closure means may include a strap secured to said collar member and having secured at one end thereof a first half of a loop-pile fastener combination such as “Velcro”, a second half of said fastener combination being secured to a second end of said strap and said strap being secured to an external surface of said collar member. This strap can extend substantially entirely around the collar member's periphery and, again, provide a significant reinforcement or stiffening effect.
In yet another alternative, the closure means may include a strap secured to said collar member and having secured at one end thereof a first half of a loop-pile fastener combination such as “Velcro”, a second half of said fastener combination being secured to a second strap and said strap and said second straps being secured to external surfaces of said collar member. In this case, extending the first and second straps around a large part of the collar member's periphery can stiffen or reinforce it.
Preferably, the split is at a peripheral location which in use of said collar is at the most forward point of said collar. It is also preferred that said parts of said collar on opposing sides of said split have formations which in use of said collar fit cooperatively against each other.
It is especially preferred that said collar member includes left and right formations on opposing sides which in use with said user in a looking-straight-ahead position are located adjacently to left and right upper surfaces of said user's thorax between said user's neck and left and right shoulders and which are shaped and extend downwardly so as to be close to but clear of said surfaces. Alternatively, these formations may in use contact said surfaces, but sufficiently lightly to allow rotation of said helmet by said user without substantial restriction.
It is also especially preferred that said collar member includes at least one downwardly depending front formation at a front part of said collar member which in use is located adjacently to and clear of a clothed surface of an upper chest portion of said user and which is adapted to contact said clothed surface of said upper chest portion in the event of a predetermined amount of forward bending of said user's neck from a normal looking-straight-ahead position. In particular, there may be two said front formations on said collar member said two front formations being laterally spaced apart from each other. This allows air to pass between them for ventilation of the helmet interior as disclosed below.
It is further especially preferred that said collar member includes a formation downwardly depending from a rear part thereof which in use is located adjacently to and clear of a the nape of the neck (or a surface of clothing thereon) and which is adapted to contact the said nape or surface of clothing in the event of a predetermined amount of rearward bending of said user's neck from a normal looking-straight-ahead position.
Said helmet retaining means may include at least one loop-and-pile fastener part secured to said collar member within said recess and positioned to mate with a cooperating part of said loop-and-pile fastener on said lower part of said helmet when said lower part is received in said recess.
Preferably, the collar member is formed at least in part from a resilient expanded plastics foam. It may even more preferably be formed as a single integral member.
The appended claims are explicitly made a part of this disclosure.
A preferred embodiment of the invention will now be described in detail by reference to the following Figures:
FIG. 1 is a perspective view of a protective collar according to the invention, together with a full-face crash helmet;
FIG. 2 is a plan view of a collar member being a component of the protective collar shown in FIG. 1 ;
FIG. 3 is a cross sectional view of the component shown in FIG. 2 , taken at Station “AA”;
FIG. 4 is a side elevation of the component shown in FIG. 2 , taken in the direction of arrow “B”;
FIG. 5 is a front view of the component shown in FIG. 2 taken in the direction of arrow “C”;
FIG. 6 is a cross-sectional sketch of a user of the collar and helmet shown in FIG. 1 , seen from ahead, with the helmet seen in transverse cross-section;
FIG. 7 is a view the same as FIG. 6 save for omission of the collar therein.
DESCRIPTION OF PREFERRED EMBODIMENT
FIG. 1 shows a protective collar 1 according to the invention, together with a full-face crash helmet 2 with which collar 1 is used. Collar 1 includes as its main component a collar member 3 formed as a single piece of expanded plastics foam of suitable resilience and deformability. Collar 1 also includes a webbing strap 4 . To one end of the strap 4 is secured a pad 6 which forms a first half of a loop-pile fastener of known type (available for example under the trade name “Velcro”). The strap 4 extends peripherally around, and is secured over most of its length by adhesive to, an external surface 5 of collar member 3 . Secured to a second end of strap 4 is a pad 7 forming a second half of the loop-pile fastener.
Collar member 3 is generally ring-shaped, with a central opening 8 within a recess 9 . Recess 9 is defined by a lower surface 10 and an inwardly-facing wall 11 upstanding from surface 10 and extending peripherally around collar member 3 . Recess 9 is so shaped and sized that a lower part 12 of helmet 2 can be received in recess 9 , snugly fitting therein around its entire periphery and with its lower rim 13 abutting surface 10 . To retain helmet 2 within recess 9 , recess 9 is provided with several loop-pile fastener halves 14 , each positioned to cooperate with loop-pile fastener halves 15 secured to helmet 2 .
In use of the collar 1 , the neck of a user 23 (not shown in FIG. 1 ) passes through opening 8 . The collar member 3 has a split 16 extending through it at its forwardmost point, so that it can be sprung apart there by a user wearing helmet 2 and placed around helmet 2 . Adjoining loop-pile fastener halves 14 and 15 then mate with each other. Then, to fully secure collar 1 in position, ends of strap 4 are passed to each other so that pads 6 and 7 abut and fasten strap 4 snugly around the surface 5 of collar member 3 . Some tension can be put in the strap 4 so that the split 16 is kept firmly closed.
Below surface 10 , collar member 3 is of a substantial (and in this preferred embodiment substantially constant) thickness, typically greater than the depth of recess 9 . Opening 8 is sized and shaped so that around most of its periphery it closely fits against the user's neck. To minimize possible discomfort, longitudinally-extending flutes 17 are provided around the periphery so that only surfaces 18 actually contact the neck. Flutes 17 allow for some ventilation and drainage of sweat from inside the helmet 2 as necessary. Hidden lines associated with the flutes 17 and surfaces 18 are omitted from FIG. 4 , for clarity.
An extension 78 of opening 8 is provided at a forward end of opening 8 . This provides a pathway for air into the helmet 2 and clearance for a user's “Adam's apple” (where applicable).
Collar member 3 is extended laterally by formations 19 and 20 which, in use of collar 1 and with the user 23 looking straight ahead, are located above those parts of his or her body between the neck and shoulders. As best seen in FIG. 5 , formations 19 and 20 have downward extensions 21 and 22 . FIG. 5 does show user 23 and it will be seen that extensions 21 and 22 are arranged to lie slightly above the user's body. Thus they provide no obstacle to user 23 turning to look to either side. (Some very slight brushing of clothing of the user 23 by extensions 21 and 22 is acceptable, however, although not preferred.) Note that FIG. 5 shows the collar member 3 only in a normal position of use of collar 1 , the strap 4 having been omitted for clarity.
Collar member 3 also has a rear neck pad 24 which extends downwardly from collar member 3 at its rear. Neck pad 24 does not in a normal driving position of user 23 contact the nape of his or her neck, but is arranged to do so in the event of a small degree of backward rotation of the user's head.
Collar member 3 also has two chest pads 25 and 26 which extend downwardly from collar member 3 at its front, on opposing sides of split 16 . Chest pads 25 and 26 do not in a normal driving position of user 23 contact his or her chest, but are arranged to contact the chest in the event of a small degree of forward rotation of the user's head.
Chest pads 25 and 26 are spaced apart laterally, thereby to define a space 27 between them. Particularly when the collar 1 is used in conditions where there is significant airflow on front surfaces of the helmet 2 and collar 1 (as for example in some open-wheel racing cars) air flows through space 27 and upwards through extension 78 of opening 18 into helmet 2 .
Because chest pads 25 and 26 , rear neck pad 24 and extensions 21 and 22 do not in a normal driving position contact the body of user 23 , the user 23 has a small but adequate amount of freedom to move the head, as necessary.
Chest pads 25 and 26 , extensions 21 and 22 and rear neck pad 24 are all separate from each other on collar member 3 , so that they operate substantially independently.
Helmet 2 is of conventional type (save for the added loop-pile fastener halves 15 ) and may have a normal chinstrap arrangement for securing on the user's head. The collar 1 is independent of, and does not significantly affect operation of, chinstrap.
External surface 5 of collar member 3 is cylindrical in the sense that its cross-sectional shape in plan view is substantially constant (although not circular) with height. This facilitates the use of a comparatively wide webbing-type strap 4 which in practice gives a degree of additional stiffening or reinforcement to collar member 3 , by being wrapped firmly around it in use of collar 1 .
Split 16 is not a simple cut in collar member 3 , but as best seen in FIG. 2 has opposing male and female faces ( 79 and 80 ) which are shaped to cooperate with each other when the strap 4 is secured around collar member 3 . This is to ensure that there is proper alignment of the parts of collar member 3 on opposing sides of the split 16 . This is also in the interests of the most secure possible retention of helmet 2 in recess 9 of collar member 3 .
FIG. 6 shows a cross-sectional sketch of user 23 , seen from ahead, wearing helmet 2 and collar 1 (both seen in cross-section) and undergoing a side impact. The impact is such that the user's head 28 and the helmet 2 are moving in the direction of arrow 29 , but are very rapidly stopping, so that they are actually subject to a rapid deceleration in the direction of arrow 29 . The net effect is equivalent to a large, short-lived lateral force acting at the combined centre of mass of the helmet 2 and head 28 with a line of action as shown by vector 39 in FIG. 6 . With helmet 2 secured within recess 9 of collar member 3 , helmet 2 and collar 1 effectively act essentially as a single unit protecting head 28 . The main forces applied to the user 23 due to deceleration of the head/helmet/collar combination will then be approximately as shown (not to scale) by the following vectors in FIG. 6 —a friction force 33 and a downward force 34 on the upper body 32 , a side force 35 applied to the neck 30 , an upward force 36 applied to the chin 31 by chinstrap 37 and a side force 38 applied by helmet 2 to head 28 . Of course, this is an idealization. These forces are actually resultants of pressure and shear stress distributions over areas of contact between the helmet/collar combination and the user 23 . It has been assumed that the head 28 is heavier than the helmet 2 , as is intended to be the case in practice, and forces developed against the top of the head 28 by chinstrap tension have been ignored as they are not relevant to this disclosure.
If the user 23 undergoes the same impact without the benefit of collar 1 , and attempts to resist his head 28 being thrown sideways, then as shown in FIG. 7 , neck 30 is subject at its base to a bending moment or torque (represented by arrow 40 ) and shear force 41 . These are large for severe impacts, and in practice the neck 30 both bends and extends and there may be serious injury to the spinal column and/or surrounding soft tissue.
Returning to FIG. 6 , the effect of the collar member 3 being closely fitting about neck 30 is that force 39 causes both forces 33 and 35 . Without such close fitting between collar member 3 and neck 30 , there would be no force 35 , and force 33 would be correspondingly larger for a given dynamic force 39 (i.e. for a given deceleration rate). Then, if such larger friction force cannot be developed, or if the collar deformation required to do so is large, lateral displacement of head 28 will be greater, with more bending and stretching of neck 30 , with higher risk of injury. That is, a close fit of neck 30 in opening 8 of collar member 3 allows more effective transfer of loads associated with a side impact to the upper body 32 and less head/neck deflection.
Exactly the same principle applies in the case of forward impacts, in which very rapid stopping throws head 28 forward. In that case, some dynamic load is transferred directly as pressure to the nape of neck 30 by collar member 3 .
Accordingly, collar 1 has better performance than a conventional collar without a close fit around the neck, or no collar at all. In the case of a conventional collar (not shown) between helmet 2 and upper body 32 and snugly fitting around neck 30 , it is believed that more of the component of lateral dynamic force 39 due to the mass of the helmet 2 would have to be absorbed by the neck 30 than in the case of collar 1 , as the better lateral support of helmet 2 in recess 9 of collar 1 is absent.
There are other advantages of the collar 1 as described above. For example, collar 1 , despite its apparent bulk, is of generally rounded shape and somewhat streamlines a wearer's helmet/neck area. Turbulence of air in the space below the helmet 2 is thought to be reduced by collar 1 . This, together with direct lateral support of neck 30 , in turn may help reduce buffeting-type uncontrolled movement of the helmet at high speeds in non-enclosed vehicles.
Many variations may be made without departing from the spirit and scope of the invention. | The invention provides a protective collar for use with a full-face crash helmet, particularly for use in motor sports. The collar is at least partially formed from a resilient material that in use extends peripherally entirely around a user's neck. The collar has a recess in which a lower part of the crash helmets is received and secured, and helmet retaining means (e.g loop-pile fastening strips) are provided for retaining the helmet within the recess. The recess has an upwardly facing bottom surface which abuts the lower part of the helmet and a peripherally extending, inwardly facing wall surface which extends upwardly from the bottom surface. The wall surface closely fits against the lower part of the helmet around the periphery of the helmet. The collar is shaped to limit movement, both laterally and in a fore-and-aft direction, of the wearer's head in the event of a violent acceleration or deceleration, such as may occur in an accident. | 0 |
FIELD OF THE INVENTION
The present invention relates to a ventilation duct construction, comprising a ventilation duct which is provided with insulation and through which air is allowed to flow, as well as a method of providing a ventilation duct. An increased fire-retardant capability of the ventilation duct is achieved by means of the invention.
Fire-retardant capability is here defined as the capability to resist such a temperature rise of the duct air as causes a temperature rise on the outside of the construction.
TECHNICAL BACKGROUND
To prevent fire from spreading in ventilation ducts, it is common to provide the ventilation ducts with some kind of insulating material, such as rock wool, which is resistant to high temperatures and thus prevents fire from spreading. Conventionally, insulation is arranged on the outside of the wall of the duct and is in most cases provided with an outer metal cover.
The ventilation ducts serve to convey air, but noise also propagates easily. By insulating, at least in some sections of the ducts, the inside of the ducts with sound-absorbing material, such as rock wool or glass wool, and lately also materials which are less fire-retardant, e.g. polyester insulation, it is possible to absorb noise efficiently. Hereinafter, sound-absorbing sections of ventilation ducts will also be referred to as sound absorbers.
In case of fire, it is very important to keep down the temperature of the outside of insulated ventilation ducts or sound absorbers as long as possible to increase the fire safety of the surroundings and close objects.
Since sound absorbers often are enlarged in cross-section compared with other ventilation duct sections and contain insulation with a limited fire-retardant capability, the problems of bulkiness and of obtaining a sufficient degree of fire-retardancy may be accentuated.
SUMMARY OF THE INVENTION
Therefore, one object of the present invention is to provide an insulated ventilation duct construction, in which the time during which the outside temperature can be kept down in case of fire is prolonged, while the construction remains compact.
It is also an object to provide a simple method which increases the fire-retardancy of an insulated ventilation duct or duct sound absorber.
According to the present invention, these and other objects which will become apparent in the following are achieved by means of a ventilation duct construction, a sound absorber construction and a method, which have the features stated in the appended claims.
The invention is thus based on the understanding that the fire-retardant capability can be increased by arranging, at least partially, a supplemental thin boundary layer outwardly of the insulated duct or the sound absorber, which boundary layer, on the one hand, provides a supplemental cover configuration having what might be considered as a heat-exchange function and, on the other, provides an additional air insulation effect.
According to one aspect of the invention, a protective or shielding sheet made of metal is thus arranged at least partially around and close to the duct and its associated insulation, not in direct contact with the insulated duct, but instead at a short distance from the same so that an air gap is formed therebetween.
Surprisingly, it has been found that this simple measure imparts a much improved fire-retardant capability to the construction. Preferably, the thermal bridge between the shielding sheet and the duct and its associated insulation is made very small, which can easily be achieved with the aid of suitably designed spacer means. Thus, the time of heating the shielding sheet is prolonged and in particular the time of heating its outside, i.e. the outside of the entire construction.
One advantage of said construction is that the shielding sheet, at least initially, has a cooling effect on the hot air in the gap which has been heated by fire. The thicker the selected shielding sheet, the better the cooling capability. The selection of the width of the air gap as well as the thickness of the shielding sheet must be adjusted to the demands on weight and space. It has been found that a satisfactory effect is obtained even when using a very thin shielding sheet and a very small air gap. The shielding sheet is made of metal, such as galvanised steel sheet or stainless steel sheet. A typical shielding sheet of galvanised steel shows a satisfactory effect even with a thickness of less than 10 mm. The shielding sheet preferably has a thickness of less than a few millimeters, more preferably about 1 mm. The size of the air gap, i.e. the distance between the shielding sheet and the insulated duct, is typically less than 50 mm, preferably less than 20 mm, more preferably less than a few millimeters, such as about 1 mm.
The shielding sheet also has another effect, namely that of distributing the heat over the shielding sheet in case it is locally exposed to a considerable temperature rise. This function is particularly pronounced if the shielding sheet is made of a material having good thermal conductivity.
According to one embodiment, the shielding sheet can be provided with through-holes to improve the circulation of air and heat exchange. This is because cold ambient air is to be drawn into the gap through openings at the ends of the shielding sheet, when the hot air leaks out of the gap through the holes of the shielding sheet. As a result, a circulation of air is provided which contributes to the cooling of the air gap and the shielding sheet. The number, shape and size of the holes can be selected depending on the desired qualities of the shielding sheet. However, the size and the number of the holes have to be chosen, since too big or too many holes could counteract the purpose of the shielding sheet. It has, however, been found that good effects are achieved also when the total area of the holes equals half the area of the shielding sheet.
Depending on the circumstances and the security aspects that must be taken into consideration, the position of the shielding sheet may vary. It is possible to surround an entire ventilation duct of about one hundred meters with a shielding sheet in accordance with the invention, preferably in separate sections so as to provide openings for the intake of air. But it is also possible to provide a ventilation duct with shielding sheet only locally along one or more specially selected sections, such as a sound absorber section. Irrespective of the above-mentioned alternatives, it is not necessary to arrange shielding sheet along the entire circumference of the ventilation duct. It is quite possible that extra protection is needed only along a part of the circumference of the duct.
If the ventilation duct is being passed through a through hole in a wall, a shielding sheet according to the invention may be provided at the location of such a section of the ventilation duct.
Thus, according to another aspect of the invention a protecting or shielding sheet is arranged at least partially around and close to a section of the duct near a wall having a through hole, through which the duct is passed. The shielding sheet comprises a first portion extending essentially in parallel with the ventilation duct, and a second portion extending essentially in parallel with the penetrated wall and being located at an end of said first portion nearest to the penetrated wall. The shielding sheet is thus arranged at such a distance that an air gap is formed between the shielding sheet and both the duct and the penetrated wall.
This second aspect of the invention is particularly advantageous in case of fire on one side of the wall through which the ventilation duct is penetrated. Such a fire may increase the temperature in the ventilation duct on said one side, the rising temperature effect propagating through the duct and thus reaching the other side of the wall. A shielding sheet on the other side will provide the inventive fire-retardant effect.
The first portion of the shielding sheet has primarily a cooling effect on the air in the gap between the ventilation duct and the first portion, while the second portion has primarily a cooling effect on the air in the gap between the penetrated wall and the second portion. Thus, the second portion helps to keep the penetrated wall at a lower temperature than would have been the case without the shielding sheet according to the invention. A relatively long second portion means more cooling capacity.
In one embodiment the first and the second portion of the shielding sheet may be integrated. They may be constructed from one and the same blank or from two different blanks brought together. Alternatively, instead of providing a shielding sheet with an integrated first and second portion, two shielding sheet may be arranged in a spaced apart relationship, i.e. in no contact with each other. One sheet will be in parallel with the ventilation duct and the other sheet will be in parallel with the penetrated wall. This achieves a practical opening between the two sheets for intake and/or outlet of air.
Suitably, insulation is provided in connection with said through hole in the penetrated wall. The insulation may for instance be packed between the outside of the duct wall and the wall defining the through hole. The insulation seals the through hole around the ventilation duct. Any, suitable insulating material may be applied. An example is mineral wool packed in the inner, middle part of the hole and the respective hole opening around the duct insulation is sealed with filling material, such as plaster or the like.
The cross-sectional shape of the ventilation duct or the sound absorber may vary. Typical shapes are rectangular and circular, but other shapes are also feasible, since the invention is not limited to any particular shape of the duct. The shape of the shielding sheet is suitably selected according to the shape of the ventilation duct or the sound absorber, and preferably in such manner that the shapes conform with each other. A shielding sheet according to the second aspect of the invention, i.e. applied at a wall penetration, will besides having a shape (said first portion) that confirms with the ventilation duct, also have a generally flat shape (said second portion) near the wall. If e.g. the ventilation duct is circular, said flat shape may be a circular ring or disc with a hole.
The manner in which the duct is insulated does not limit the scope of the invention. It is, for instance, possible to arrange, on the outside of the wall of the duct, a standard insulation, the outside of which is a metal cover adjacent to which the shielding sheet is arranged with the air gap. A ventilation duct section with sound-absorbing insulation is also possible, the shielding sheet being arranged so that an air gap forms between the same and the outer cover of the sound absorber. Other types of insulation are, of course, also feasible, such as thermal insulation.
As already mentioned, the shielding sheet can be kept at a suitable distance from the ventilation duct with the aid of spacer means so that said air gap forms. As examples of spacer means, mention can be made of pins, screws, rivets and distance plates which are arranged between and fixed to the shielding sheet and/or the wall of the ventilation duct or the insulation placed thereon, with or without a cover. In case of said arrangement in connection with a penetrated wall, spacer means may be arranged between the penetrated wall and the shielding sheet (or second portion of the shielding sheet) parallel to that wall.
The design of the spacer means should allow the thermal bridge to be minimised. Thus the spacer means should be small and limited to a small number. It is also possible to form the air gap without any connection at all, and thus without a thermal bridge, between the shielding sheet and the ventilation duct. One possibility is to equip the construction with magnets so that the shielding sheet is kept “floating” about the ventilation duct. If there is enough space, another possibility of completely avoiding thermal bridges is to provide the shielding sheet with an outer suspension which is connected to external holding elements.
Even if the shielding sheet has been discussed so far in connection with both ordinary insulated ventilation ducts and duct sound absorbers (ventilation duct sections with sound-proofing), the function of the shielding sheet is the same, irrespective of the type of duct to which it is applied. The use of a shielding sheet according to the invention does not have to be limited to these variants but could also, for instance, be used in connection with heat or condensation insulated ducts.
Besides the discussed ventilation duct construction, the present invention, as already mentioned, relates to a method which increases the fire-retardant capability of an insulated ventilation duct. According to the method, this is achieved by placing a shielding sheet made of metal externally at least partially around the insulated duct at such a distance from the same that an air gap forms between the shielding sheet and the insulated duct. The invention is thus also applicable to existing installations, both to a conventional existing sound absorber and to other ventilation duct sections.
The invention can also facilitate the mounting of a fire-protected sound absorber in a section of a ventilation duct. It is thus possible, for instance, to remove the fire insulation in the desired section, perforate the duct wall to “let out the sound”, arrange sound insulation with an outer cover which forms the duct wall on the perforated duct wall and finally arrange the shielding sheet according to the invention around the outer cover so that an air gap forms between the shielding sheet and the outer cover.
One common way of arranging a sound absorber in an existing ventilation duct is to cut off the duct and insert by splicing the sound absorber. The one skilled in the art will realise that a sound absorber equipped with a shielding sheet according to the present invention can also be arranged in a ventilation duct in the same manner.
The invention makes it possible to lower the requirements placed on the absorbing material of a sound absorber as concerns fire-retardancy for the benefit of improved absorbency, resulting in the possibility of reducing the dimensions in the transverse direction, while maintaining the same total fire-retardancy level.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 schematically shows a longitudinal cross-section of a ventilation duct construction according to an embodiment of the present invention.
FIG. 2 schematically shows a cross-section of the construction in FIG. 1 along the line II—II.
FIG. 3 schematically shows a perspective view of the sound absorber in FIGS. 1 and 2.
FIG. 4 schematically shows a longitudinal cross-section of a ventilation duct construction according to another embodiment of the present invention.
FIG. 5 schematically shows a cross-section of the construction in FIG. 4 along the line V—V.
FIG. 6 shows a diagram in which a comparison is made between a sound absorber having a shielding sheet according to the present invention and a sound absorber without a shielding sheet.
FIG. 7 schematically shows a longitudinal cross-section of a ventilation duct construction according to yet another embodiment of the present invention.
FIGS. 8A and 8B schematically show perspective views of the shielding sheet in FIG. 7 .
FIG. 9 schematically shows a longitudinal cross-section of a ventilation duct construction according to yet another embodiment of the present invention.
FIG. 10 schematically shows a longitudinal cross-section of a ventilation duct construction according to yet another embodiment of the present invention.
FIG. 11 schematically shows a longitudinal cross-section of a ventilation duct construction according to a further embodiment of the present invention.
FIG. 12 schematically shows a longitudinal cross-section of a ventilation duct construction according to a further embodiment of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 schematically shows a longitudinal cross-section of a ventilation duct construction 1 according to an embodiment of the present invention. The Figure illustrates part of a ventilation duct 4 through which air is allowed to flow. The ventilation duct 4 is provided with a sound absorber section 6 , which is fixed by means of annular flanges 7 projecting over and surrounding the wall 12 of the ventilation duct 4 . In usual manner, the sound absorber 6 comprises an annular sound insulation 8 which is made of glass wool and which is open inwards to absorb noise propagating inside the ventilation duct 4 . The sound insulation 8 is placed at an outer cover 10 of the sound absorber 6 . On each side of the sound absorber 6 , a fire insulation 14 made of rock wool is arranged on the outside of the wall 12 of the ventilation duct 4 , said fire insulation 14 being delimited outermost by a metal cover 16 . The wall 12 of the ventilation duct 4 and its associated fire insulation 14 and metal cover are joined to the sound absorber 6 by means of the flanges 7 , so that the wall 12 of the ventilation duct 4 merges into the duct-forming outer cover 10 . A sleeve-shaped shielding sheet 18 which has a thickness of about 0.7 mm and is made of galvanised steel sheet is arranged around the outer cover 10 of the sound absorber 6 in accordance with the invention. Rivets 20 which are arranged between the shielding sheet 18 and the outer cover 10 keep the shielding sheet 18 at a distance of about 1 mm from the outer cover 10 so that an air gap 22 forms therebetween. Openings 23 at the ends of the sheet allow cold ambient air to enter into the gap. The shielding sheet is also perforated (which is shown in FIG. 3 ), and therefore a satisfactory air circulation with a cooling effect is obtained. The sound absorber 6 which is provided with the shielding sheet 18 obtains considerably increased fire-retardancy compared with a sound absorber without a shielding sheet. This will be discussed in more detail in connection with FIG. 6 .
The shielding sheet 18 preferably does not form part of a mechanically continuous fluid path with the insulated duct 4 . In other words, fluid that flows through the duct 4 is not directed such that it flows through any passage defined by the shielding sheet 18 either before or after flowing through the duct.
FIG. 2 schematically shows a cross-section of the construction in FIG. 1 along the line II—II. It is apparent that in this embodiment the sound absorber is round in cross-section.
FIG. 3 schematically shows a perspective view of the sound absorber in FIGS. 1 and 2, a perforated shielding sheet 18 being illustrated, which provides a satisfactory air circulation, resulting in cooling of the shielding sheet 18 and the air gap 22 .
FIG. 4 schematically shows a longitudinal cross-section of a ventilation duct construction 2 according to another embodiment of the present invention. In this Figure, the same reference numerals are used as in FIG. 1 for equivalent construction components. In contrast to the embodiment in FIG. 1, the wall 12 of the ventilation duct, adjacent to the sound absorber section, merges into the wall 24 of a foraminated pipe, which is an integral part of the sound absorber. The foraminated pipe through which noise is emitted serves as a support for the sound insulation 8 resting thereon. Also in this case, the sound insulation 8 is, in usual manner, provided with an outer cover 10 . Yet another difference is that the shielding sheet 26 according to this embodiment is arranged not only around the sound absorber 6 , but also around adjoining sections of the ventilation duct part. Consequently, increased fire-retardancy is obtained for the critical sound absorber section as well as adjoining sections. In the Figure, the shielding sheet 26 is divided so that openings 28 allow the inflow of cooling air in a manner corresponding to that of the openings 23 in FIG. 1. A very good effect is, however, obtained for the shielding sheet 26 also without the openings 28 .
FIG. 5 schematically shows a cross-section of the construction in FIG. 4 along the line V—V. As shown, the sound absorber in this embodiment is quadrangular in cross-section, which is to illustrate that the sound absorber is connected to a ventilation duct with quadrangular cross-section.
FIGS. 1-5 are only shown for the purpose of exemplification and thus not according to scale. In addition, it goes without saying that the person skilled in the art will understand that there are many other embodiments within the scope of the invention. The sound absorber in FIG. 1 may, for instance, be provided with a foraminated pipe according to the construction in FIG. 4, just like the sound absorber in FIG. 4 can be designed in a different manner, without a foraminated pipe. Moreover, the cross-sectional shapes are exchangeable, as is also the length of the shielding sheet, and it is possible to select either a perforated or a non-perforated shielding sheet.
FIG. 6 shows a diagram in which a comparison is made between a sound absorber with a shielding sheet according to the present invention and a sound absorber without a shielding sheet. Fire tests were performed by connecting a furnace to an inlet end of the respective sound absorbers, so that the air duct of the sound absorbers was connected with the furnace air. The temperature of the furnace was increased according to a standard fire curve (to about 600° C. after 6 min and up to slightly more than 900° C. after 60 min). Several thermoelements were placed on the outside of the respective constructions, i.e. on the outside of the shielding sheet and the outside of the cover of the sound absorber, respectively. In the Figure, temperature values measured by a thermoelement, which was placed in the centre of the respective constructions, are compared. The dashed curve shows the temperature change on the outside of an ordinary sound absorber without any shielding sheet. The unbroken curve shows the temperature change on the outside of an inventive shielding sheet which is arranged on a sound absorber. As clearly appears from the curves, a marked difference is obtained between the sound absorber with a shielding sheet and the sound absorber without a shielding sheet. The steep inclination at the beginning of the dashed curve is also worth noting. After only not quite ten minutes, the outside temperature of the conventional sound absorber increases dramatically, whereas when comparing with the sound absorber provided with a shielding sheet an even and slowly increasing temperature can be noted. As already suggested, measurements have also been made at other measuring points than in the centre of the sound absorbers, such as at the inlet end, at the other end and at a plurality of points in between. However, for the sake of clarity we have chosen to illustrate the difference with the measurement in the centre. It can, however, be mentioned that at all measuring points the sound absorber which is provided with shielding sheet exhibited the lowest temperatures after the 60 min long fire test. At certain measuring points, there was a difference of as much as 150° C. between the sound absorber with shielding sheet and the sound absorber without shielding sheet. The shielding sheet which was used in the test was not perforated and had a thickness of 0.7 mm and was placed around the sound absorber so that the air gap had a width of 1.0 mm. The sound absorber had the following dimensions: length 500 mm, width 285 mm, height 215 mm.
FIG. 7 schematically shows a longitudinal cross-section of a ventilation duct construction 40 according to yet another embodiment of the present invention. The Figure illustrates part of a ventilation duct 42 through which air is allowed to flow. The ventilation duct construction 40 also comprises a wall 44 having a through hole 46 , through which the ventilation duct 42 is passed. The through hole 46 surrounding the ventilation duct 42 is sealed by means of insulation 48 , such as fire insulation of any suitable type, e.g. mineral wool. The two ends of the through hole 46 are suitably defined by a respective plaster coat 50 , which boarders on the outer surface of the penetrated wall 44 . A shielding sheet 52 , made of galvanised steel sheet is arranged around the ventilation duct wall 54 on one side of the penetrated wall 44 . The shielding sheet 52 comprises two portions. A first portion 56 of the shielding sheet 52 has essentially a tubular or sleeve shape, similarly to the shielding sheets shown in FIGS. 1-5. The first portion 56 extends in parallel with the ventilation duct 42 and surrounds the same. A second portion 58 of the shielding sheet 52 is generally ring-shaped, in the form of a disc with a hole. The second portion 58 is located at the end of the first portion 56 nearest to the penetrated wall 44 , and extends in parallel with the penetrated wall 44 . Thus, the second portion 58 is like a thin first portion end having an enlarged diameter (see FIGS. 8 A and 8 B). Rivets 60 which are arranged between the shielding sheet 52 and both the duct wall 54 and the penetrated wall 44 keep the shielding sheet 52 at a distance of about 1 mm from both the duct wall 54 and the penetrated wall 44 so that an air gap 62 forms therebetween. Openings 64 at the end of the sheet 52 allow cold ambient air to enter into the gap 62 . In case of fire at a location on the other side of the penetrated wall 44 , i.e. the side not provided with the shielding sheet 52 , the air inside the adjacent ventilation duct 42 will be affected. The temperature in the ventilation duct 42 will rise, and this temperature rise will propagate along the ventilation duct 42 through the penetrated wall 44 . The shielding sheet 52 will have the previously described function of increasing the fire-retardant capability of the ventilation duct construction 40 . The angled shielding sheet 52 will delay temperature rise on the outside of the construction 40 caused by heat from the inside of the ventilation duct 42 as well as heat penetrating the through hole 46 and the insulation 48 . It is to be noted that the penetrated wall 44 is to be regarded as a part of the ventilation duct construction 40 .
FIGS. 8A and 8B schematically show perspective views of the shielding sheet 52 in FIG. 7 . In FIG. 8A the second portion 58 is seen nearest to the viewer, while in FIG. 8B the second portion 58 is seen farthest from the viewer. As is seen from these Figures, the shielding sheet 52 comprises a first tubular portion 56 and a second thin annular portion 58 . The second portion 58 is arranged perpendicularly to the end of the first portion 56 . The diameter of the second portion 58 is suitably large enough to shield at least the insulation sealing the through hole in the penetrated wall. It is to be understood that for a ventilation duct having a rectangular, square or other non-circular cross-section, the shielding sheet is suitably designed with corresponding cross-sections.
FIG. 9 schematically shows a longitudinal cross-section of a ventilation duct construction 70 according to yet another embodiment of the present invention. This ventilation duct construction 70 is similar to that of FIG. 7 . However, in this case a shielding sheet 72 , 74 is provided on both sides of a penetrated wall 76 . This embodiment increases the fire-retardant capability of the construction on both sides of the wall 76 .
FIG. 10 schematically shows a longitudinal cross-section of a ventilation duct construction 80 according to yet another embodiment of the present invention. Unlike the previously shown embodiments with a penetrated wall, the longitudinal axis of the ventilation duct 82 does not conform with the normal of the penetrated wall 84 . Therefore the shielding sheet 86 is designed so that the longitudinal axis of the first portion 88 does not conform with the normal of the plane of the second portion 90 , but runs in parallel with the extension of the duct 82 . The second portion 90 extends in parallel with the penetrated wall 84 . Furthermore, FIG. 10 illustrates that on the outside of the ventilation duct wall 92 a fire insulation 94 is arranged. The fire insulation is delimited outermost by a metal cover 96 (as in FIGS. 1 and 4 ). The shielding sheet 86 according to this embodiment is arranged not only in the vicinity of the penetrated wall 84 but also further away along the ventilation duct 82 . Consequently, increased fire-retardancy is obtained for the entire shielded ventilation duct. In FIG. 10 as in FIG. 4, the shielding sheet 86 is divided so that openings 98 allow the inflow of cooling air.
FIG. 11 schematically shows a longitudinal cross-section of a ventilation duct construction 110 according to a further embodiment of the present invention. In this embodiment, as in FIG. 10, a ventilation duct 112 is provided with insulation 114 at the duct wall 116 . Shielding sheets 118 are provided on both sides of a penetrated wall 120 . In this embodiment, instead of having an integrated sheet with a first and a second portion, a first shielding sheet 122 and a second shielding sheet 124 is provided on each side of the penetrated wall 120 . The first shielding sheet 122 and the second shielding sheet 124 are spaced apart, i.e. they are not in contact with each other. Thus, an opening 126 is created between the first shielding sheet 122 and the second shielding sheet 124 for intake and/or outflow of air. Furthermore additional respective openings 128 , 130 are provided on both the first shielding sheet 122 and the second shielding sheet 124 , for further improvement of the air circulation.
It is to be understood that even though certain embodiments have been shown in FIGS. 7-11 others are possible as well. Thus, the shown features may be combined in numerous ways. It is also to be noted that the through hole may be without sealing insulation, if the penetrated wall in itself is insulating. The through hole around the ventilation duct may be without insulation, and only be sealed at the outer surfaces of the penetrated wall by means of gypsum.
FIG. 12 schematically shows a longitudinal cross-section of a ventilation duct construction 140 according to a further embodiment of the present invention. In this embodiment a ventilation duct 142 is provided with a hatch 144 , which may be opened for accessing and cleaning the ventilation duct 142 . The sections of the ventilation duct 142 adjacent to the hatch 144 are in usual manner provided with insulation 146 . The hatch 144 itself is in this Figure without insulation, however, the person skilled in the art understands that the inside of the hatch 144 may also be provided with insulation. A sleeve-shaped shielding sheet 148 made of galvanised steel sheet is arranged partly around the section with the hatch in accordance with the invention. Spacer pins 150 which are arranged between the shielding sheet 148 and the hatch 144 keep the shielding sheet 148 at a distance of about 1 mm from the hatch 144 so that an air gap 152 forms therebetween. Openings 154 at the ends of the sheet 148 allow cold ambient air to enter into the gap 152 .
It should be noted that the embodiments shown in the Figures are not to scale and are only illustrated schematically for elucidatory purposes.
It is to be understood that even though certain embodiments have been shown numerous modifications and variations can be made without departing from the scope of the present invention defined in the accompanied claims. | The present invention relates to an ventilation duct construction and a method which increases the fire-retardant capability of a ventilation duct. According to the invention, an improved fire-retardant capability of a ventilation duct or sound absorber is obtained by providing the ventilation duct with a shielding sheet at a distance from the same so that an air gap is formed therebetween. The time during which the outside temperature of the construction can be kept down is prolonged, while the construction remains compact. | 5 |
This application claims the benefit of U.S. Provisional Application No. 60/240,492, filed Oct. 13, 2000.
FIELD OF THE INVENTION
The present invention relates, in general, to an improved surgical biopsy instrument and, more particularly, to a remote thumbwheel mechanism for use in a surgical biopsy instrument.
BACKGROUND OF THE INVENTION
The diagnosis and treatment of patients with cancerous tumors, pre-malignant conditions, and other disorders has long been an area of intense interest in the medical community. Non-invasive methods for examining tissue and, more particularly, breast tissue include palpation, X-ray imaging, MRI imaging, CT imaging, and ultrasound imaging. When a physician suspects that tissue may contain cancerous cells, a biopsy may be done using either an open procedure or in a percutaneous procedure. In an open procedure, a scalpel is used by the surgeon to create an incision to provide direct viewing and access to the tissue mass of interest. The biopsy may then be done by removal of the entire mass (excisional biopsy) or a part of the mass (incisional biopsy). In a percutaneous biopsy, a needle-like instrument is inserted through a very small incision to access the tissue mass of interest and to obtain a tissue sample for examination and analysis. The advantages of the percutaneous method as compared to the open method are significant: less recovery time for the patient, less pain, less surgical time, lower cost, less disruption of associated tissue and nerves and less disfigurement. Percutaneous methods are generally used in combination with imaging devices such as X-ray and ultrasound to allow the surgeon to locate the tissue mass and accurately position the biopsy instrument.
Generally there are two ways to percutaneously obtain a tissue sample from within the body, aspiration or core sampling. Aspiration of the tissue through a fine needle requires the tissue to be fragmented into small enough pieces to be withdrawn in a fluid medium. Application is less intrusive than other known sampling techniques, but one can only examine cells in the liquid (cytology) and not the cells and the structure (pathology). In core biopsy, a core or fragment of tissue is obtained for histologic examination which may be done via a frozen or paraffin section. The type of biopsy used depends mainly on various factors and no single procedure is ideal for all cases.
A number of core biopsy instruments which may be used in combination with imaging devices are known. Spring powered core biopsy devices are described and illustrated in U.S. Pat. Nos. 4,699,154, 4,944,308, and Re. 34,056. Aspiration devices are described and illustrated in U.S. Pat. Nos. 5,492,130; 5,526,821; 5,429,138 and 5,027,827.
U.S. Pat. No. 5,526,822 describes and illustrates an image-guided, vacuum-assisted, percutaneous, coring, breast biopsy instrument which takes multiple tissue samples without having to re-puncture the tissue for each sample. The physician uses this biopsy instrument to “actively” capture (using the vacuum) the tissue prior to severing it from the body. This allows the physician to sample tissues of varying hardness. The instrument described in U.S. Pat. No. 5,526,822 may also be used to collect multiple samples in numerous positions about its longitudinal axis without removing the instrument from the body. A further image-guided, vacuum-assisted, percutaneous, coring, breast biopsy instrument is described in commonly assigned U.S. Ser. No. 08/825,899, filed on Apr. 2, 1997 and in U.S. Pat. Nos. 6,007,497; 5,649,547; 5,769,086; 5,775,333; and 5,928,164. A handheld image-guided, vacuum-assisted, percutaneous, coring, breast biopsy instrument is described in U.S. Pat. No. 6,086,544 and in U.S. Pat. No. 6,120,462. The instrument described therein moves drive motors and other electronic components into a control unit separate from and remotely located from the biopsy probe. Biopsy probe cutter rotational and translational motion is transferred from the motors in the control unit to the biopsy probe via flexible coaxial cables. This arrangement improves the cleanability of the reusable hardware that remains in close proximity to the biopsy site as well as improves the life and durability of the electric motors and electronic components now remotely located from the biopsy probe. The biopsy instrument described and illustrated in U.S. Pat. No. 6,086,544 and in U.S. Pat. No. 6,120,462 was designed primarily to be a “hand held” instrument to be used by the clinician in conjunction with real time ultrasound imaging. Several imageguided, vacuum-assisted, percutaneous, coring, breast biopsy instruments are currently sold by Ethicon Endo-Surgery, Inc. under the Trademark MAMMOTOME™.
The majority of breast biopsies done today, however, utilize an x-ray machine as the imaging modality. Using x-ray requires that the biopsy instrument be affixed to the x-ray machine by some type of bracket arrangement. Since the biopsy instrument is fixed to a portion of the x-ray machine there is now a need for a means to conveniently rotate the biopsy probe once it is advanced into the breast in order to accurately position the vacuum port at the distal end of the probe.
In U.S. Pat. No. 5,769,086 a biopsy probe is disclosed which includes an electric motor, connected to the proximal end of the biopsy probe via a gear train. Activating the motor causes rotation of the piercing element of the biopsy probe so that multiple tissue specimens may be obtained by the clinician at any location around the center axis of the probe. U.S. Pat. No. 5,649,547 illustrates and describes a biopsy instrument which includes a “thumb wheel” at the proximal end of the biopsy probe piercing element. The thumb wheel provides a convenient place for the clinician to grasp the piercing element to manually rotate the biopsy probe about its center axis so that multiple tissue samples could be taken at any position, as determined by the clinician, about the axis of the probe. There are a couple of problems, however, that become evident when this arrangement is put into clinical use. First, when the biopsy probe is used in combination with and mounted to an x-ray machine, it can be difficult for the clinician to get access to the thumb wheel portion of the biopsy probe because of brackets, hoses, and other obstructions in the area around the probe.
It would, therefore, be advantageous to design an image-guided, vacuum assisted, percutaneous, coring, cable driven breast biopsy instrument which may be conveniently mounted to an x-ray machine, and incorporate in it a remotely located means to manually rotate the probe, located in an area away from the surgical site and easily accessible by the clinician. It would further be advantageous to design an image-guided, vacuum assisted, percutaneous, coring, cable driven breast biopsy instrument which may be conveniently mounted to an x-ray machine which would incorporate a port rotation knob located at the proximal end of the biopsy instrument.
SUMMARY OF THE INVENTION
The present invention is directed to a biopsy instrument including a base assembly including a firing mechanism movably attached to a distal end of the base assembly, a probe assembly detachably mounted to the base assembly and a drive assembly detachably mounted to the cutter assembly and including a flexible drive shaft operatively connected to the cutter. The probe assembly including a piercer assembly and a cutter assembly detachably affixed to the base assembly. The piercer assembly including a piercer and a probe mount supporting the piercer. The piercer including a distal port, a vacuum lumen, a cutter lumen and a first gear mechanism affixed to a proximal end of the piercer. The cutter assembly includes a cutter adapted to move through the cutter lumen, an adjustment wheel extending from a proximal end of the cutter assembly and a drive rod connected to the adjustment wheel, the drive rod being operatively connected to the first gear mechanism.
The present invention is further directed to a biopsy instrument including a base assembly including a firing mechanism moveably attached to a distal end of the base assembly, a probe assembly moveably attached to the base assembly and a drive assembly detachably mounted to the cutter assembly, the drive assembly including a flexible drive shaft operatively connected to the cutter. The probe assembly including a piercer assembly which includes a piercer moveable from a proximal position to a distal position, a probe mount supporting the piercer and a cutter assembly detachably affixed to the base assembly. The piercer including a distal port, a vacuum port, a cutter lumen and a first gear affixed to a proximal end of the piercer. The probe mount including a second gear affixed to a drive shaft and the second gear meshing with the first gear and a fork coupling detachably mountable to the firing mechanism. The cutter assembly including a cutter adapted to move through the cutter lumen, an adjustment wheel extending from a proximal end of the cutter assembly and a drive rod connected to the adjustment wheel, the drive rod being slideably affixed to a proximal end of the drive shaft such that rotation of the adjustment wheel rotates the piercer as the piercer moves from the proximal position to the distal position.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features of the invention are set forth with particularity in the appended claims. The invention itself, however, both as to organization and methods of operation, together with further objects and advantages thereof, may best be understood by reference to the following description, taken in conjunction with the accompanying drawings in which:
FIG. 1 is an isometric view of a surgical biopsy system of the present invention comprising a biopsy device, control unit, and remote.
FIG. 2 is an isometric view of the biopsy probe assembly and base assembly, shown separated, with the upper base housing shown removed.
FIG. 3 is an isometric view of the biopsy probe assembly with the top shell and bottom shell shown separated to expose internal components.
FIG. 4 is an exploded isometric view of the biopsy probe assembly of the present invention without the top shell and bottom shell.
FIG. 5 is a longitudinal section view of the distal end of the biopsy probe assembly.
FIG. 6 is an exploded isometric view of the lower transmission assembly of the present invention.
FIG. 7 is an isometric view of the transmission showing the upper transmission assembly exploded.
FIG. 8 is an isometric view of the biopsy probe assembly and base assembly, separated, with the upper base housing not shown, as viewed from the proximal end.
FIG. 9 is an exploded isometric view of the firing mechanism of the present invention.
FIG. 10 is an exploded isometric view of an embodiment of the firing fork assembly.
FIG. 11 is an exploded isometric view of the triggering mechanism of the present invention.
FIG. 12 is an isometric view of the safety latch.
FIG. 13 is an isometric view of the safety button.
FIG. 14 is a top view of the firing mechanism of the present invention showing the mechanism in the post-fired position.
FIG. 15 is a partial, plan sectional view of the firing mechanism in the post-fired position showing the firing latch and firing rod.
FIG. 16 is a top view of the firing mechanism of the present invention showing the mechanism in the pre-fired position.
FIG. 17 is a partial, plan sectional view of the firing mechanism in the pre-fired position showing the firing latch and firing rod.
FIG. 18 is a top view of the firing mechanism of the present invention showing the arming mechanism in the relaxed position.
FIG. 19 is a partial, plan sectional view of the firing mechanism in the relaxed position showing the firing latch and firing rod.
FIG. 20 is an isometric view of the safety latch and safety button shown in the locked position.
FIG. 21 is an isometric view of the safety latch and safety button shown in the firing position.
FIG. 22 is an exploded isometric view of an alternate embodiment of the firing fork assembly.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is an isometric view showing a surgical biopsy system 10 comprising biopsy device 40 , a control unit 100 , and remote 20 . Biopsy device 40 comprises probe assembly 42 operatively and removably attached to base 44 . Base 44 is removably attached to a moveable table 12 such as a stereotactic guidance system as may be found on mammographic x-ray machines, an example of which is Model MAMMOTEST PLUS/S available from Fischer Imaging, Inc., Denver, Colo.
Probe assembly 42 includes an elongated piercer 70 having a piercer tip 72 for penetrating soft tissue of a surgical patent. Piercer 70 comprises a piercer tube 74 and vacuum chamber tube 76 . Vacuum chamber tube 76 of piercer 70 may be fluidly connected to control unit 100 . Similarly, axial vacuum to probe assembly 42 may be obtained by fluid connection to control unit 100 . MAMMOTOME™ system tubing set Model No. MVAC1 available from Ethicon Endo-Surgery Inc., Cincinnati, Ohio is suitable for use to permit detachable fluid connection of lateral vacuum line 32 and axial vacuum line 34 to control unit 100 . Lateral vacuum line 32 and axial vacuum line 34 are made from a flexible, transparent or translucent material, such as silicone tubing, allowing for visualization of the material flowing through them. Lateral connector 33 and axial connector 35 are female and male luer connectors, respectively, commonly known and used in the medical industry. Base 44 is operatively connected to control unit 100 by control cord 26 , translation shaft 22 , and rotation shaft 24 . Translation shaft 22 and rotation shaft 24 are preferably flexible so as to permit for ease of mounting of biopsy device 40 to moveable table 12 .
Control unit 100 is used to control the sequence of actions performed by biopsy device 40 in order to obtain a biopsy sample from a surgical patient. Control unit 100 includes motors and a vacuum pump, and controls the activation of vacuum to probe assembly 42 and the translation and rotation of the cutter (not visible) in probe assembly 42 . A suitable Control unit 100 is a MAMMOTOME™ system control module Model No. SCM12 with software Model No. SCMS1 available from Ethicon Endo-Surgery Inc., Cincinnati, Ohio.
Remote 20 is operatively and removably connected to control unit 100 . Remote 20 may be used by the surgical biopsy system operator to control the sequence of actions performed by biopsy device 40 . Remote 20 may be a hand operated or foot operated device. A suitable remote 20 is MAMMOTOME™ Remote Key-pad Model No. MKEY1 available from Ethicon Endo-Surgery Inc., Cincinnati, Ohio.
FIG. 2 is an isometric view showing probe assembly 42 and base 44 separated. Upper base housing 50 is normally fixedly attached to base 44 , but has been shown removed from base 44 to provide a view of transmission 301 . Top shell tab 46 is located on the distal end of cantilever beam 41 and projects above the top surface of gear shell 18 . Top shell tab 46 inserts into tab window 48 in upper base housing 50 upon assembly of probe assembly 42 to base 44 . Once probe assembly 42 and base 44 are properly assembled, top shell tab 46 must be pushed down through tab window 48 by the user before probe assembly 42 and base 44 can be separated. A plurality of raised ribs 58 is provided on gear shell 18 to improve the user's grip on the instrument. Post 14 extends above the top surface of base shell 38 and inserts into keyhole 16 (not visible) located on the underside of gear shell 18 . Tube slot 68 in upper base housing 50 provides clearance for axial vacuum line 34 . First tang 54 and second tang 56 protrude from opposite sides of probe housing 52 and insert into first recess 64 and second recess 66 , respectively, in firing fork 62 . The proximal end of probe housing 52 fits slidably within gear shell 18 and firing fork 62 fits slidably within base shell 38 . Thus, once probe assembly 42 and base 44 are operatively assembled, probe housing 52 and firing fork 62 are able to move a fixed linear distance in a distal and proximal direction in front of gear shell 18 and base shell 38 . FIGS. 1 and 2 show probe housing 52 and firing fork 62 in their most distal position.
FIGS. 3 and 4 are views of probe assembly 42 . FIG. 3 is an isometric view of probe assembly 42 with the top shell 17 and bottom shell 19 shown separated, the top shell 17 rotated ninety degrees, to expose internal components. FIG. 4 is an exploded isometric view of the same probe assembly 42 without top shell 17 or bottom shell 19 . Gear shell 18 is formed from top shell 17 and bottom shell 19 , each injection molded from a rigid, biocompatible thermoplastic material such as polycarbonate. Upon final assembly of probe assembly 42 , top shell 17 and bottom shell 19 are joined together by ultrasonic welding along joining edge 15 , or joined by other methods well known in the art. Probe assembly 42 comprises piercer 70 having an elongated, metallic piercer tube 74 and a piercer lumen 80 (see FIGS. 4 and 5 ). On the side of the distal end of piercer tube 74 is port 78 for receiving tissue to be extracted from the surgical patient. Joined along side piercer tube 74 is an elongated, tubular, metallic vacuum chamber tube 76 having a vacuum lumen 82 (see FIGS. 4 and 5 ). Piercer lumen 80 is in fluid connection with vacuum lumen 82 via a plurality of vacuum holes 77 (See FIG. 5) located in the bottom of the “bowl” defined by port 78 . Vacuum holes 77 are small enough to remove the fluids but not large enough to allow excised tissue portions to be removed through lateral vacuum line 32 , which is fluidly connected to vacuum lumen 82 . A metallic, sharpened piercer tip 72 is fixedly attached to the distal end of piercer 70 . It is designed to penetrate soft tissue, such as the breast tissue of a female surgical patient. In the present embodiment piercer tip 72 is a three sided, pyramidal shaped point, although the tip configuration may also have other shapes.
Refer now, momentarily, to FIG. 5 . FIG. 5 is a section view of the distal end of probe assembly 42 , illustrating primarily probe housing 52 , piercer 70 , and union sleeve 90 . The proximal end of piercer 70 is fixedly attached to union sleeve 90 having a longitudinal bore 84 through it. Union sleeve 90 contains a first o-ring groove 27 and second o-ring groove 28 , spaced apart so as to allow for a traverse opening 37 between them in fluid communication with longitudinal bore 84 . First o-ring 29 and second o-ring 30 mount in first o-ring groove 27 and second o-ring groove 28 , respectively. Sleeve gear 36 is integral to union sleeve 90 and is located at its most proximal end. Lead-in cone 25 is a conical shaped metallic structure that attaches to the proximal end of union sleeve 90 . Union sleeve 90 is inserted into housing bore 57 located in the distal end of probe housing 52 , and rotatably supports the proximal end of piercer 70 . Positioning wheel 31 slides over piercer 70 and the distal end of union sleeve 90 and rotatably attaches to probe housing 52 , hence trapping lead-in cone 25 and union sleeve 90 within housing bore 57 in the distal end of probe housing 52 . Locating projection 11 on the distal end of union sleeve 90 functionally engages alignment notch 13 in positioning wheel 31 . Thus, rotating positioning wheel 31 likewise causes the rotation of piercer 70 . This allows port 78 to be readily positioned anywhere within the 360° axis of rotation of piercer 70 .
Referring again to FIGS. 3 and 4, housing extension 47 is located at the proximal end of probe housing 52 . Housing flange 53 is located at the most proximal end of housing extension 47 on probe housing 52 and is assembled just inside of top shell front slot 55 in top shell 17 . Shell insert 39 is assembled into top shell front slot 55 . First insert tab 59 and second insert tab 60 , both located on shell insert 39 , engage first shell recess 61 and second shell recess 63 , located within top shell front slot 55 , respectively. Thus, upon complete assembly of probe assembly 42 , the most proximal end of probe housing 52 containing housing flange 53 is trapped within gear shell 18 , yet slideable along housing extension 47 distal and proximal within top shell front slot 55 . Tissue sampling surface 65 is a recessed surface within probe housing 52 which provides a surface where each tissue sample will be deposited during the operation of the present invention, prior to retrieval by the clinician.
An elongated, metallic, tubular cutter 96 (see FIG. 5) is axially aligned within cutter bore 51 of probe housing 52 , longitudinal bore 84 of union sleeve 90 , and piercer lumen 80 of piercer 70 so that cutter 96 may slide easily in both the distal and proximal directions. Cutter 96 has a cutter lumen 95 through the entire length of cutter 96 . The distal end of cutter 96 is sharpened to form a cutter blade 97 for cutting tissue held against cutter blade 97 as cutter 96 is rotated. The proximal end of cutter 96 is fixedly attached to the inside of cutter gear bore 102 of cutter gear 98 . Cutter gear 98 may be metal or thermoplastic, and has a plurality of cutter gear teeth 99 , each tooth having a typical spur gear tooth configuration as is well known in the art. Cutter seal 79 is a lip type seal and is fixedly attached to the proximal end of cutter gear 98 , and is made of a flexible material such as silicone. Tissue remover 132 fits rotatably and slidably through cutter seal 79 . Probe seal 81 is also a lip type seal made of a flexible material such as silicone rubber and is fixedly inserted into the proximal end of cutter bore 51 at the proximal end of probe housing 52 . Cutter 96 fits rotatably and slidably through cutter seal 79 . Cutter seal 79 and probe seal 81 operate to prevent fluids from entering the space within gear shell 18 during a surgical biopsy procedure.
Still in FIGS. 3 and 4, cutter gear 98 is driven by elongated drive gear 104 having a plurality of drive gear teeth 106 designed to mesh with cutter gear teeth 99 . The function of elongated drive gear 104 is to rotate cutter gear 98 and cutter 96 as they translate in both longitudinal directions. Elongated drive gear 104 is preferably made of a thermoplastic material, such as liquid crystal polymer. Distal drive axle 108 projects from the distal end of elongated drive gear 104 and mounts rotatably into an axle support rib (not visible) molded on the inside of top shell 17 and held in place by first gear support rib located on bottom shell 19 . Gear shaft 110 projects from the proximal end of drive gear 104 and is rotatably supported by a gear shaft slot 69 located in the proximal end of top shell 17 and by second gear support rib 137 located on bottom shell 19 . Drive gear slot 101 is located on the most proximal end of gear shaft 110 as a means for rotationally engaging drive gear 104 .
Still referring to FIGS. 3 and 4, cutter carriage 124 is provided to hold cutter gear 98 and to carry cutter gear 98 as it is rotated and translated in the distal and proximal directions. Cutter carriage 124 is preferably molded from a thermoplastic material and is generally cylindrically shaped with a threaded bore 126 through it and with carriage foot 130 extending from its side. Carriage foot 130 has a foot recess 128 formed into it and foot slot 127 for rotatably holding cutter gear 98 in the proper orientation for cutter gear teeth 99 to mesh properly with drive gear teeth 106 . Lower carriage guide 103 projects down from cutter carriage 124 and slidably engages lower guide slot 107 molded on the inside surface of bottom shell 19 . Upper carriage guide 105 projects up from carriage foot 130 and slidably engages a upper guide slot 109 molded on the inside of top shell 17 . Cutter carriage 124 is attached via threaded bore 126 to elongated screw 114 , which is parallel to drive gear 104 . Screw 114 has a plurality of conventional lead screw threads 116 and is preferably made of a thermoplastic material. The rotation of elongated screw 114 in one direction causes cutter carriage 124 to move distally, while the reverse rotation of elongated screw 114 causes cutter carriage 124 to move proximally. As a result, cutter gear 98 moves distally and proximally according to the direction of the screw rotation, which in turn advances cutter 96 distally or retracts it proximally. In the present embodiment, elongated screw 114 is shown with a right hand thread so that clockwise rotation (looking from the proximal to distal direction) causes cutter carriage 124 to translate in the proximal direction. Distal screw axle 118 projects from the distal end of elongated screw 114 and mounts rotatably into an axle support rib (not visible) molded on the inside of top shell 17 and held in place by first screw support rib 111 located on bottom shell 19 . Screw shaft 120 projects from the proximal end of elongated screw 114 and is rotatably supported by a screw shaft slot 71 located in the proximal end of top shell 17 and by second screw support rib 112 located on bottom shell 19 . Lead screw slot 122 is located on the most proximal end of screw shaft 120 as a means for rotationally engaging elongated screw 114 .
At this point in the detailed description it should be pointed out that during the operation of the biopsy instrument cutter 96 translates in either direction between a fully retracted position, just proximal to tissue sampling surface 65 as referenced by cutter blade 97 , and a fully deployed position wherein cutter blade 97 is located just distal to port 78 . As cutter 96 translates between these end points there are a number of intermediate positions wherein adjustments may be made to the cutter rotational and translational speed as commanded by control unit 100 . These intermediate positions and the adjustments made to the cutter depend on the programming of control unit 100 .
Referring now to FIG. 5, the distal end of lateral vacuum line 32 is attached to lateral fitting 92 located on the distal end of probe housing 52 . Lateral fitting 92 has lateral hole 117 through it along its axis in fluid communication with housing bore 57 . Lateral hole 117 in lateral fitting 92 is positioned within housing bore 57 such that when union sleeve 90 is inserted into housing bore 57 lateral hole 117 is located in the space created between first and second o-rings, 29 and 30 respectively. Locating lateral hole 117 in the space between first and second o-rings 29 and 30 , respectively, allows for the communication of fluids between vacuum lumen 82 and control unit 100 .
Referring again to FIGS. 3 and 4, axial vacuum line 34 is fluidly attached to tissue remover support 129 which is in turn fluidly attached to the proximal end of an elongated, metallic, tubular tissue remover 132 . Axial vacuum line 34 allows for the communication of fluids between piercer lumen 80 , cutter lumen 95 , and control unit 100 . Tissue remover support 129 fits into axial support slot 73 located in the proximal end of top shell 17 . Strainer 134 is located on the distal end of tissue remover 132 and functions to prevent passage of fragmented tissue portions through it and into control unit 100 . Tissue remover 132 inserts slidably into cutter lumen 95 of cutter 96 . During the operation of the biopsy instrument, tissue remover 132 is always stationary, being fixedly attached at its proximal end to tissue remover support 129 which is fixed within axial support slot 73 located in the proximal end of top shell 17 . When cutter 96 is fully retracted to its most proximal position, the distal end of tissue remover 132 is approximately even with the distal end of cutter 96 (see FIG. 5 ). The distal end of cutter 96 , when at its most proximal position, and probe housing 52 at its most distal position, is slightly distal to housing wall 67 which is proximal and perpendicular to tissue sampling surface 65 .
Probe rotation rod 85 is an elongated, solid metal rod. Rotation rod gear 86 is a spur gear fixedly attached to the distal end of probe rotation rod 85 . Rotation rod flat 87 is located at the proximal end of probe rotation rod 85 . Rotation rod flat 87 is approximately one-third to one-half the rod diameter in depth and extending from its proximal end approximately one inch in length. Rotation rod flat 87 thus creates a “D” shaped geometry at the proximal end of probe rotation rod 85 . Rod bushing 88 is made of molded thermoplastic and is cylindrical in shape. At its distal end is bushing bore 89 which is a “D” shaped hole approximately one inch in depth, designed to slidably receive the proximal end of probe rotation rod 85 . Rod bushing 88 fits rotatably into axial support slot 73 below tissue remover support 129 at the proximal end of top shell 17 . The longitudinal position of rod bushing 88 is fixed by the raised sections on both sides of bushing groove 93 , upon assembly into the proximal end of top shell 17 . Rod bushing drive slot 91 is located on the most proximal end of rod bushing 88 as a means for rotationally engaging rod bushing 88 . Rotation gear 86 is rotatably fixed into gear cavity 115 on the underside of probe housing 52 , the opening being in communication with housing bore 57 (see FIG. 5 ). Rotation rod gear 86 operably engages sleeve gear 36 located at the proximal end of union sleeve 90 . The distal end of probe rotation rod 85 with rotation rod gear 86 attached is rotatably fixed to the underside of probe housing 52 by rotation gear cover 94 . Rotation gear cover 94 is molded from a thermoplastic material and is fixedly attached to probe housing 52 by four raised cylindrical pins which press fit into four holes (not visible) in probe housing 52 . Probe rotation rod 85 inserts rotatably and slidably through rod hole 43 in shell insert 39 . The proximal end of probe rotation rod 85 slidably engages bushing bore 89 in rod bushing 88 . Thus, rotation of rod bushing 88 causes rotation of probe rotation rod 85 which is fixedly attached to rotation rod gear 86 causing rotation of union sleeve 90 which is fixedly attached to piercer 70 , which contains port 78 .
It is important for the user of the surgical biopsy system of the present invention to be able to “fire” the piercer 70 into the tissue of a surgical patient. It is also important that the user be able to rotate piercer 70 about its axis so as to properly position port 78 , regardless of linear position of piercer 70 pre-fired vs. post-fired (positions discussed later). The slidable interface between probe rotation rod 85 and rod bushing 88 plays an important role in providing this capability. Probe rotation rod 85 follows the linear movement of piercer 70 , while the linear movement of rod bushing 88 is restricted by the fact that it is rotatably attached to top shell 17 . Thus the “D” shaped geometry on the proximal end of rotation rod 85 and the “D” shaped hole in the distal end of rod bushing 88 , designed to slidably receive the proximal end of rotation rod 85 , permit the user to turn port rotation knob 45 , which is operably connected to rod bushing 88 through a chain of elements described later, and effect the rotation of piercer 70 , irrelevant of the linear position of piercer 70 .
Bottom shell 19 fixedly attaches to top shell 17 as described earlier. Its function is to hold in place and contain the elements previously described, which have been assembled into top shell 17 . Keyhole 16 is centered at the distal end of bottom shell 19 . It slidably and removably engages post 14 (See FIG. 2 ), permitting probe assembly 42 to be operatively and removably connected to base 44 . First screw support rib 111 and second screw support rib 112 are each integrally molded to bottom shell 19 and support the distal and proximal ends, respectively, of elongated screw 114 . First gear support rib 136 and second gear support rib 137 likewise are each integrally molded to bottom shell 19 and support the distal and proximal ends, respectively, of elongated drive gear 104 . Rod bushing support rib 139 integrally molded to bottom shell 19 supports the distal end of rod bushing 88 .
FIG. 6 is an exploded isometric view of lower transmission assembly 302 . Translation shaft 22 and rotation shaft 24 is each a flexible coaxial cable comprising a flexible rotatable center core surrounded by a flexible tubular casing, as is well known in the art. At their most proximal ends is provided a coupling means for removably and operatively connecting translation shaft 22 and rotation shaft 24 to control unit 100 . The distal ends of translation shaft 22 and rotation shaft 24 each insert through first boot bore 309 and second boot bore 311 , respectively. Flex boot 303 is molded from a thermoplastic elastomer such as, for example, polyurethane, and functions as a “flex relief” for translation shaft 22 , rotation shaft 24 , and control cord 26 . Rotation shaft ferrule 305 is a metallic tubular structure comprising a through bore with a counter bore at its proximal end for fixedly attaching, via crimping or swaging as is well known in the art, to the outer tubular casing of rotation shaft 24 . At the distal end of rotation shaft ferrule 305 is a flared, counter bored section for receiving first bearing assembly 315 . A suitable example of first bearing assembly 315 is Model No. S9912Y-E1531PSO, available from Stock Drive Products, New Hyde Park, N.Y. Rotation shaft adapter 319 is made of stainless steel and has a proximal end with a counter bore. Its proximal end inserts through the bore of first bearing assembly 315 and the counter bore slips over the distal end of the rotatable center core of rotation shaft 24 and is fixedly attached by crimping or swaging. The distal end of rotation shaft adapter 319 is inserted through the bore in first bevel gear 321 and is fixedly attached by a slotted spring pin. Similarly, translation shaft ferrule 307 is a metallic tubular structure comprising a through bore with a counter bore at its proximal end for fixedly attaching, via crimping or swaging, to the outer tubular casing of translation shaft 22 . At the distal end of translation shaft ferrule 307 is a flared, counter bored section for receiving thrust washer 317 . Translation shaft adapter 323 is made of stainless steel and has a proximal end with a counter bore. Its proximal end inserts through the bore of thrust washer 317 and the counter bore slips over the distal end of the rotatable center core of translation shaft 22 and is fixedly attached by crimping or swaging. The distal end of translation shaft adapter 323 is slotted as a means to engage the proximal end of encoder shaft 312 , which extends through encoder 310 . Encoder 310 communicates information to control unit 100 about the translation position and translation speed of cutter 96 . Encoder 310 includes an electrical cord containing a plurality of electrical conductors, which has an electrical connector affixed at its most distal end for removable electrical connection to printed circuit board 262 (See FIG. 9 ). A suitable miniature encoder 310 is commercially available as Model sed10-300-eth2 from CUI Stack, Inc. Encoder shaft 312 has two opposing flats on its proximal end, which engage translation shaft adapter 323 , and a cylindrical distal end which is inserted into a counter bore in the proximal end of gear adapter 316 and is fixedly attached by a slotted spring pin. The distal end of gear adapter 316 is inserted through the bore of second bearing assembly 318 , through the bore of shaft spacer 322 , and finally through the bore in second bevel gear 325 which is fixedly attached to gear adapter 316 by a slotted spring pin.
Encoder housing assembly 329 comprises left encoder housing half 326 and right encoder housing half 328 , which are molded thermoplastic shells. When assembled, left encoder housing half 326 and right encoder housing half 328 encase encoder 310 and capture the distal end of translation shaft 22 and rotation shaft 24 . Left encoder housing half is attached to transmission plate 330 (see FIG. 7) using a cap screw. Encoder 310 is placed in first shell cavity 332 , preventing rotational or lateral movement of the outer housing of encoder 310 . The distal end of rotation shaft ferrule 305 rests in second shell cavity 334 , which prevents lateral movement of rotation shaft 24 . The distal end of translation shaft ferrule 307 rests in third shell cavity 336 , which again prevents lateral movement of translation shaft 22 . Second bearing assembly 318 rests in fourth shell cavity 338 . Right encoder housing half 328 , containing essentially a mirror image of the cavities found inside left encoder housing half 326 , assembles to left encoder housing half 326 and transmission plate 330 via two cap screws.
Still referring to FIG. 6, control cord 26 is flexible and contains a plurality of electrical conductors for communication information between biopsy device 40 and control unit 100 (see FIG. 1 ). At the proximal end of control cord 26 is provided a means of removable electrical connection to control unit 100 . The distal end of control cord 26 inserts through third boot bore 313 located in flex boot 303 . Control cord strain relief 369 is a flexible thermoplastic material and is over molded to the distal end of control cord 26 and is fixedly attached to transmission plate 330 in a recessed area at strain relief bore 371 (see FIG. 7 ), to restrict linear and rotational movement of the distal end of the cord. The most distal end of control cord 26 contains a connector for removably and electrically affixing control cord 26 to printed circuit board 262 (see FIG. 9 ).
FIG. 7 is an isometric view of transmission 301 . Upper transmission assembly 304 is shown exploded. Translation coupling assembly 337 consists of translation drive coupling 340 , third bearing assembly 344 , first coupling spacer 348 , and third bevel gear 350 . Third bearing assembly 344 is press fit into first counter bore 345 in transmission plate 330 . Translation drive coupling 340 has a flat bladed distal end which will operatively couple with lead screw slot 122 (see FIG. 8) located at the proximal end of elongated screw 114 . The cylindrical proximal end of translation drive coupling 340 inserts through first counter bore 345 , through the bore of third bearing assembly 344 , through the bore of first coupling spacer 348 , and finally through the bore in third bevel gear 350 which is fixedly attached to translation drive coupling 340 by a slotted spring pin. The gear teeth of third bevel gear 350 mesh with the gear teeth of second bevel gear 325 . Thus, rotation of the center core of translation shaft 22 results in the rotation of translation drive coupling 340 . When translation drive coupling 340 is operatively coupled to elongated screw 114 via lead screw slot 122 , rotation of translation shaft 22 causes rotation of elongated screw 114 which results, as discussed earlier, in the distal or proximal translation of cutter 96 , depending on the direction of translation shaft 22 rotation.
In a similar manner, rotation coupling assembly 339 consists of rotation drive coupling 342 , fourth bearing assembly 346 , second coupling spacer 349 , and fourth bevel gear 351 . Fourth bearing assembly 346 is press fit into second counter bore 347 in transmission plate 330 . A suitable example of fourth bearing assembly 346 , as well as second and third bearing assemblies 318 and 344 , respectively, is available as Model No. S9912Y-E1837PSO, available from Stock Drive Products, New Hyde Park, N.Y. Rotation drive coupling 342 has a flat bladed distal end which will operatively couple with drive gear slot 101 (see FIG. 8) located at the proximal end of elongated drive gear 104 . The cylindrical proximal end of rotation drive coupling 342 inserts through second counter bore 347 , through the bore of fourth bearing assembly 346 , through the bore of second coupling spacer 349 , and finally through the bore in fourth bevel gear 351 , which is fixedly attached to rotation drive coupling 342 by a slotted spring pin. The gear teeth of fourth bevel gear 351 mesh with the gear teeth of first bevel gear 321 . Thus, rotation of the center core of rotation shaft 24 results in the rotation of rotation drive coupling 342 . When rotation drive coupling 342 is operatively coupled to elongated drive gear 104 via drive gear slot 101 , rotation of rotation shaft 24 causes rotation of elongated drive gear 104 , which results in the rotation of cutter 96 . A suitable example of first, second, third, and fourth bevel gears 321 , 325 , 350 , and 351 , respectively, is Model No. A1M-4-Y32016-M available from Stock Drive Products, New Hyde Park, N.Y.
Continuing in FIG. 7, port drive coupling 353 has a flat bladed distal end which will operatively couple with rod bushing drive slot 91 (see FIG. 8) located at the proximal end of rod bushing 88 . The cylindrical proximal end of port drive coupling 353 inserts through the bore in first port gear 355 , which is fixedly attached by a slotted spring pin, then inserted through first port coupling bore 359 . First coupling washer 362 slips over the proximal end of drive port coupling 353 and first coupling e-ring 364 snaps into a groove at the most proximal end of drive port coupling 353 , which now rotatably secures the assembly to transmission plate 330 . Knob post 367 is made of stainless steel, is generally cylindrical, and has a flange on its most distal end and a flat approximately one-third to one-half its diameter in depth and extending from its proximal end one half inch in length. Knob post 367 inserts through the bore of second port gear 357 , which is fixedly attached by a slotted spring pin to the distal end of knob post 367 . Suitable examples of first and second port gears 355 and 357 , respectively, are available as Model No. A1N1-N32012, available from Stock Drive Products, New Hyde Park, N.Y. The proximal end of knob post 367 is inserted through second port coupling bore 360 until second port gear 357 aligns and meshes with first port gear 355 . Second coupling washer 363 slips over the proximal end of knob post 367 and second coupling e-ring 365 snaps into a groove located adjacent to the distal end of knob post 367 , thus rotatably securing the assembly to transmission plate 330 . Port rotation knob 45 fixedly attaches to the proximal end of knob post 367 . A suitable port rotation knob 45 is Model No. PT-3-P-S available from Rogan Corp., Northbrook, Ill. Thus, when port drive coupling 353 is operatively coupled to rod bushing 88 via rod bushing drive slot 91 , user rotation of port rotation knob 45 causes rotation of rod bushing 88 which results in the rotation of piercer 70 . This allows port 78 to be readily positioned anywhere within the 360° axis of rotation of piercer 70 .
Transmission plate 330 attaches to the proximal end of upper base shell 161 via two screws.
There is an important benefit derived from the design of transmission 301 just described. The fact that the translation shaft 22 , rotation shaft 24 , and control cord 26 enter the biopsy device 40 at a right angle to the device's center axis permits for a short overall length for the biopsy device. This allows the device to fit into a smaller area than would accommodate a device with the shafts protruding directly out the back (proximal end) parallel to the center axis.
FIG. 8 is an isometric view of probe assembly 42 and base 44 , as viewed from their proximal ends. Upper base housing 50 is not shown so as to permit a clear view of transmission 301 fully assembled. Also clearly visible are lead screw slot 122 , drive gear slot 101 , and rod bushing drive slot 91 , which operably connect to transmission 301 as previously described.
FIG. 9 is an exploded isometric view of firing mechanism 160 . Upper base shell 161 is shown exploded and lower base shell 204 is shown exploded and rotated 90 degrees clockwise. Also exploded and rotated 90 degrees clockwise for clarity is printed circuit board 262 and frame screw 163 .
Firing mechanism 160 , shown in FIG. 9, operates to fire the distal end of probe assembly 42 into tissue. Base shell 38 (see FIG. 2) supports and houses firing mechanism 160 , and is assembled from upper base shell 161 and lower base shell 204 . Base hooks 165 on lower base shell 204 insert into base slots 162 in upper base shell 161 to enable assembly of the components to create base shell 38 . Frame screw 163 inserts through a clearance hole in frame bottom 204 and fastens into firing latch block 242 to tie upper base shell 161 and lower base shell 204 together.
Firing fork 62 extends from firing mechanism 160 through to the exterior of base shell 38 to accept probe housing 52 of probe assembly 42 (see FIG. 2 ). FIG. 9 shows firing fork 62 in its most distal allowable position and shows other components of firing mechanism 160 in appropriate positions for firing fork 62 to be at its most distal allowable position.
Upon mating of the probe assembly 42 with the base 44 , first tang 54 and second tang 56 insert into first recess 64 and second recess 66 , respectively, in firing fork 62 at the distal end of firing fork assembly 164 . Features on firing fork 62 also include probe slot 167 , which is approximately “U” shaped to accept probe assembly 42 , and clearance slot 169 , allowing clearance for probe rotation rod 85 .
Firing fork assembly 164 , shown exploded in FIG. 10, is a unique assembly detachable from the rest of firing mechanism 160 without the use of tools. Firing fork 62 slides over the outer diameter of firing spade 178 while firing fork keys 181 insert into firing spade slots 180 . Firing spade slots 180 prevent rotation of firing fork 62 relative to firing spade 178 . Firing spade 178 possesses a threaded internal diameter at its distal end and a proximal spade end 196 at its proximal end. Proximal spade end 196 can comprise a flattened section, resembling, for example, the working end of a flathead screwdriver. The threaded diameter at the distal end of firing spade 178 receives screw 182 to hold firing fork 62 to firing spade 178 . The head 184 of screw 182 abuts the distal end of firing spade 178 upon tightening. Abutting the head 184 of screw 182 against the distal end of firing spade 178 prevents tightening of the screw against the firing fork 62 . The head 184 of screw 182 and the proximal end 186 of firing spade slot 180 provide proximal and distal stops for firing fork 62 while allowing slight axial play.
Firing spacer 188 attaches at the proximal end of firing spade 178 with the aid of dowel pins 190 . Firing spacer 188 slips onto and is rotatable relative to firing spade 178 . It should be noted that minimizing the clearance between the inside diameter of firing spacer 188 and the outside diameter of firing spade 178 improves the stability of firing fork assembly 164 , an important attribute.
Near the proximal end of firing spacer 188 , easily visible depth marker line 189 is inscribed. Dowel pins 190 press into receiving holes 192 on firing spacer 188 and ride within firing spade groove 194 to allow rotation of firing spacer 188 relative to firing spade 178 while preventing axial movement of firing spacer 188 relative to firing spade 178 . A threaded internal diameter at the proximal end of firing spacer 188 facilitates assembly and removal of the firing fork assembly 164 for cleaning.
FIG. 9 shows that firing fork assembly 164 threads onto end fitting 166 , pinned at the distal end of firing fork shaft 168 . End fitting 166 can be made of a soft stainless steel for easy machining of slot and threads while firing fork shaft 168 can be made of a hardenable stainless to accommodate induced stress. Proximal spade end 196 fits into spade slot 198 of end fitting 166 to prevent rotation of firing fork assembly 164 relative to firing fork shaft 168 . The threaded internal diameter of the proximal end of firing spacer 188 screws onto the threaded outer diameter of end fitting 166 to removably attach firing fork assembly 164 . Small firing bushings 170 , fashioned from a plastic such as acetal, support firing fork shaft 168 and allow it to move proximally and distally. Proximal saddle support 172 and distal saddle support 173 , machined into upper base shell 161 , support small firing bushings 170 while long clamp plate 174 and short clamp plate 175 capture and retain small firing bushings 170 into proximal and distal saddle supports 172 and 173 , respectively. Long clamp plate 174 and short clamp plate 175 can attach to proximal saddle support 172 and distal saddle support 173 using fasteners, such as, for example, clamp plate mounting screws 176 . Flanges at each end of the small firing bushings 170 bear against the proximal and distal sides of saddle supports 172 and clamp plates 174 to restrain small firing bushings 170 from moving proximally and distally with the movement of firing fork shaft 168 . Additional support is gained by the large firing bushing 200 surrounding firing spacer 188 . Large firing bushing 200 , split for easy assembly, resides in firing bushing housing 202 machined into upper base shell 161 and lower base shell 204 .
Firing fork shaft 168 carries other parts that facilitate the operation of firing mechanism 160 . Spring collar roll pin 212 fixedly attaches spring collar 214 to firing fork shaft 168 . Shock pad 216 adheres to the distal side of spring collar 214 and contacts distal interior wall 218 of base shell 38 when firing fork shaft 168 is in its distal position. Shock pad 216 can be made from many shock-absorbing materials, such as, for example, rubber. Main spring 217 surrounds firing fork shaft 168 and bears against the distal side of distal saddle support 173 and the proximal side of spring collar 214 to force firing fork shaft 168 distally. Magnet holder roll pin 208 fixedly attaches magnet holder 206 to firing fork shaft 168 . Magnet 210 is crimped into magnet holder 206 . Nearer the proximal end of firing fork shaft 168 , firing main link pin 224 passes through firing fork shaft slot 225 to hold firing fork shaft 168 to carriage 220 . Firing main link pin 224 also captures curved firing levers 222 retaining them to the carriage 220 . Firing main link pin 224 is flanged on one end. The other end of firing main link pin 224 extends through carriage 220 to retain carriage 220 , firing fork shaft 168 , and curved firing levers 222 , where it is retained by welding to the lower curved firing lever.
Curved firing levers 222 and firing linkages 226 drive the arming of firing mechanism 160 . Curved firing levers 222 pin to firing linkages 226 using firing link pins 228 which are welded to firing levers 222 . Firing linkages 226 in turn pin to upper base shell 161 using frame link dowel pins 230 pressed into upper base shell 161 . Long clamp plate 174 retains firing linkages 226 using clamp plate mounting screws 176 . Each pinned joint of curved firing levers 222 , firing linkages 226 , and carriage 220 is rotatably movable about the axis of the pin.
Each curved firing lever 222 has a portion that extends laterally outwards through a slot located on either side of base shell 38 (See FIG. 2 ). A curved firing lever end 232 is attached to each curved firing lever 222 on the extension of curved firing lever 222 external to base shell 38 . Curved firing lever end 232 provides a convenient user interface for arming the firing mechanism. Arming the mechanism will be described later. The coil of torsion spring 234 surrounds each pinned joint of curved firing levers 222 and firing linkages 226 . The legs of link torsion springs 234 extend outwardly to hook into curved firing levers 222 and firing linkages 226 , applying a torque rotating them relative to each other.
Locating firing linkages 226 and curved firing levers 222 at different distances from upper base shell 161 allows them clearance to pass by each other upon operation. Curved firing levers 222 have bends to offset them in a direction perpendicular to upper base shell 161 . The offset bends let them move within planes at different distances from upper base shell 161 while having the curved firing lever ends emerge from the slot created for that purpose in upper base shell 161 . Spacer 223 separates the links on the pin 230 . Having a curved firing lever 222 and firing linkage 226 on each side of the longitudinal centerline allows access by the user to operate firing mechanism 160 from either side of base shell 38 .
Fasteners secure a printed circuit board 262 to lower base shell 204 and latch block 242 . Printed circuit board 262 contains Hall-effect switch 264 for sensing the proximity of magnet 210 . A suitable Hall-effect switch 264 is Model No. A3142ELT available from Allegro Microsystems, Inc., Worcester, Mass. When firing fork 168 and associated magnet 210 are in the most proximal position (pre-fired position, as described later), magnet 210 is held in a position near Hall-effect switch 264 .
FIG. 11 is an exploded isometric view of triggering mechanism 235 , seen in FIG. 9 . Triggering mechanism 235 safely latches and fires firing fork shaft 168 . Triggering mechanism 235 comprises firing latch 236 , firing latch block 242 , firing button shaft 244 and roller 241 , firing latch spring 246 , firing button shaft spring 247 , safety block 248 , safety latch 250 , safety latch torsion spring 251 , safety latch cover 252 , and firing button 254 .
Firing latch block 242 encloses the proximal portion of firing latch 236 and serves as a mounting platform for components of triggering mechanism 235 . Firing latch pin 237 and firing block pin 239 rigidly retain firing latch block 242 to upper base shell 161 . Firing latch pin 237 rotatably pins firing latch 236 to upper base shell 161 while passing through firing latch block 242 . Firing latch 236 pivots within a slot in upper base shell 161 . Firing latch spring 246 is compressed between firing latch block 242 and firing latch 236 , thereby forcing the distal end of firing latch 236 towards firing fork shaft 168 . Firing latch 236 possesses a firing latch hook 238 at its distal end, which removably latches into a firing fork shaft retainer 240 located at the proximal end of firing fork shaft 168 . Firing button shaft 244 slidably moves proximally and distally within a bore in firing latch block 242 and has roller 241 rotatably pinned to its distal portion to engage firing latch 236 to cause rotation of firing latch 236 . Firing button shaft spring 247 forces firing button shaft 244 proximally. Firing button shaft 244 is retained by safety block 248 , which is mounted to the proximal side of firing latch block 242 . Safety latch 250 resides within a counter bore on the proximal side of safety block 248 and is retained by safety latch cover 252 . Fasteners such as screws hold safety latch cover 252 in place.
Safety latch 250 is designed to facilitate locking and unlocking of the firing mechanism. Safety latch 250 can be rotated within the counter bore on safety block 248 through a rotation angle, while safety latch torsion spring 251 has extending legs hooked into safety block 248 and safety latch 250 to apply torque to safety latch 250 . Safety block 248 defines a locked position safety latch stop 245 and an unlocked position safety latch stop 243 separated by the rotation angle. Safety latch handle 249 extends radially from safety latch 250 to facilitate grasping and rotating of safety latch 250 by the user. Safety latch handle 249 also forms surfaces to abut safety latch stops 245 and 243 to limit the rotation angle. In the locked position, safety latch torsion spring 251 forces safety latch handle 249 against the locked position safety latch stop 245 , while in the unlocked position, the user forces safety latch handle 249 against unlocked position safety latch stop 243 . In the illustrated embodiment of the invention, the rotation angle through which safety latch 250 can be rotated is about thirty-five degrees. FIG. 12 shows that safety latch 250 contains two firing button stops 256 with one firing button stop 256 on each side of the longitudinal axis of firing button 254 at assembly. The firing button stops 256 interact with firing button 254 to effect locking (preventing lateral movement) and unlocking (allowing lateral movement) of firing button 254 .
FIG. 13 shows an isometric view of firing button 254 . Firing button 254 fixedly attaches to firing button shaft 244 (see FIG. 11 ), extends proximally through the center of safety latch 250 (see FIG. 12 ), and presents a proximal, flattened, cylindrical thumb pad 257 located at its most proximal end to the user. Firing button 254 comprises a smaller firing button outer diameter 258 having narrow flats 259 and wide flats 261 angularly offset from each other by the rotation angle traveled by safety latch 250 . Larger firing button outer diameter 260 is free of flats. A distal contact surface 255 exists proximally of narrow flats 259 and is substantially perpendicular to the longitudinal axis of firing button 254 . Firing button stops 256 , located on safety latch 250 , are separated by a distance slightly larger than the distance between wide flats 261 and less than the smaller firing button outer diameter 258 . Firing button stops 256 can flex in the radial direction, but resist flexing in the axial direction. The difference in stiffness in different directions can be accomplished by, for example, different thicknesses of the firing button stops 256 in the axial direction and in the radial direction.
When safety latch 250 is in the locked position, pushing firing button 254 will force distal contact surface 255 against firing button stops 256 . Firing button stops 256 prevent further proximal axial movement of firing button 254 because of rigidity in the axial direction.
Following is a functional description of the operation of the firing mechanism of the present invention:
A user arms and fires the firing mechanism during use of the probe assembly 42 in a surgical procedure. The user begins in the fired position depicted in FIGS. 14 and 15, grasps one of the curved firing lever ends 232 , and moves outboard end of curved firing lever 222 proximally. This begins action wherein each grasped curved firing lever 222 , each firing linkage 226 , carriage 220 , and upper base shell 161 act as four-bar linkage systems with upper base shell 161 being the stationary link and carriage 220 being a translational link. Motion can be described of all three movable links relative to the upper base shell 161 . Either curved firing lever end 232 can be moved by the user. Duplicity exists in the illustrated embodiment of the invention to facilitate user access from either side of base 44 .
Rotating either curved firing lever 222 in a direction that moves the curved firing lever end 232 proximally effects motion of the two members pinned to curved firing member 222 . Curved firing member 222 transfers motion through one pinned joint to carriage 220 to move it proximally along firing fork shaft 168 . Curved firing member 222 also transfers motion through a second pinned joint to firing linkage 226 , rotating the pinned joint towards firing fork shaft 168 . Firing linkage 226 is pinned to stationary upper base shell 161 and rotates about the pinned joint located on upper base shell 161 .
Carriage 220 , driven by curved firing member 222 , translates proximally along firing fork shaft 168 carrying main link pin 224 within firing fork shaft slot 225 until firing main link pin 224 reaches the proximal end of firing fork shaft slot 225 . Further proximal motion of carriage 220 and firing main link pin 224 begins to drive proximal motion of firing fork shaft 168 . Firing fork shaft 168 translates proximally through small firing bushings 170 .
As firing fork shaft 168 translates proximally, it carries with it attached firing fork assembly 164 . Firing fork shaft 168 also carries proximally attached spring collar 214 , decreasing the distance between spring collar 214 and distal saddle support 173 . Main spring 217 , located between spring collar 214 and distal saddle support 173 , becomes more compressed exerting more force against spring collar 214 . Firing fork shaft 168 continues to move proximally and continues to compress main spring 217 until the proximal end of firing fork shaft 168 reaches firing latch 236 (see FIG. 15 ). The proximal end of firing fork shaft 168 contacts firing latch 236 and exerts a force rotating it out of the path of proximally advancing firing fork shaft 168 . The proximal end of firing fork shaft 168 and the distal end of firing latch 236 have contoured surfaces to act as cams to assist in lifting firing latch 236 . Rotating firing latch 236 compresses firing latch spring 246 , exerting a force to hold firing latch 236 onto the proximal end of firing fork shaft 168 . Once the firing fork shaft retainer 240 has proceeded proximally to a position under firing latch hook 238 , firing latch spring 246 urges firing latch hook 238 into firing fork shaft retainer 240 by rotating firing latch 236 towards firing fork 168 . Firing assembly 160 is now in the pre-fire position shown in FIGS. 16 and 17.
The user can now release curved firing lever end 232 . Once the user releases curved firing lever end 232 , main spring 217 applies force urging firing fork 168 distally along its axis. The distal force moves firing fork shaft retainer 240 towards firing latch hook 238 extending down into firing fork shaft retainer 240 (see FIG. 19 ). The proximal wall of firing fork shaft retainer 240 is angled so that the reactive force of the proximal wall of firing fork shaft retainer 240 against firing latch hook 238 rotates firing latch hook 238 further into the firing fork shaft retainer 240 , preventing inadvertent release. The proximal wall of firing latch hook 238 is angled to mate with the angle of the proximal wall of firing fork shaft retainer 240 . After the user has released curved firing lever end 232 , link torsion springs 234 apply torque to curved firing levers 222 and firing linkages 226 rotating them towards each other. Rotating curved firing levers 222 and firing linkages 226 towards each other initiates motion that returns carriage 220 to its distal position. With firing fork 168 held by firing latch 236 while firing levers 222 and firing linkages 226 are in the most distal position, firing mechanism 160 is in the relaxed position shown in FIGS. 18 and 19. When carriage 220 returns to its distal position, curved firing levers 222 contact stops on the sides of raised bosses on upper base shell 161 .
Firing fork shaft 168 has now carried magnet 210 (see FIG. 9) which is located within magnet holder 206 proximally into a position near Hall-effect switch 264 on printed circuit board 262 . Hall-effect switch 264 senses the presence of magnet 210 and communicates with control unit 100 that firing fork 168 is in a proximal position and ready to fire.
Safety latch 250 “guards” firing button 254 . In the locked position shown in FIG. 20, firing button stops 256 on the safety latch 250 are located distally of distal contact surface 255 on firing button 254 . Firing button stops 256 on safety latch 250 are also located on either side of narrow flats 259 (see FIG. 13 ). Smaller firing button outer diameter 258 is larger than the distance between firing button stops 256 . Attempting to push firing button 254 distally will cause distal contact surface 255 to contact firing button stops 256 . The rigidity of the firing button stops 256 in the axial direction prevents further distal movement of the firing button and prevents inadvertent firing of the mechanism.
After the user has determined the proper location in which to insert the piercer 70 of biopsy device 40 into a surgical patient, the user can now unlock and fire firing mechanism 160 . Unlocking and firing the mechanism requires two separate actions, rotating the safety latch 250 and pressing the firing button 254 . The operator first grasps safety latch handle 249 to rotate safety latch 250 against the torque applied to it by safety latch torsion spring 251 (not visible). FIG. 21 shows rotating safety latch 250 so that safety latch handle 249 travels from locked position safety latch stop 245 to unlocked position safety latch stop 243 which aligns firing button stops 256 with wide flats 261 on smaller firing button outer diameter 258 . Since the distance between firing button stops 256 is larger than the distance between wide flats 261 , clearance now exists for wide flats 261 to pass between firing button stops 256 . Safety latch 250 is now in the “firing” position.
In the next step, the operator presses firing button 254 by placing force on cylindrical thumb pad 257 to urge firing button 254 distally. When firing button 254 is pressed, wide flats 261 move between firing button stops 256 allowing firing button 254 to proceed distally. Firing button 254 , attached to firing button shaft 244 , pushes firing button shaft 244 distally. The roller 241 on firing button shaft 244 contacts the cam surface on firing latch 236 to rotate firing latch 236 so that firing latch hook 238 lifts out of firing fork shaft retainer 240 (see FIG. 19 ). Once firing latch hook 238 is clear of firing fork shaft retainer 240 , main spring 217 drives firing fork shaft 168 distally carrying firing fork assembly 164 and piercer 70 of probe assembly 42 towards the target. Distal motion of firing fork shaft 168 continues until shock pad 216 contacts distal interior wall 218 of base shell 38 (see FIG. 14 ). Hall-effect switch 264 senses the departure of magnet 210 distally and communicates the departure to control unit 100 .
After firing the firing mechanism 160 the user releases firing button 254 , then releases safety latch handle 249 . When the user releases firing button 254 , firing button shaft spring 247 forces firing button shaft 244 proximally. Firing button 254 moves proximally as well, returning distal contact surface 255 and firing button smaller diameter 258 proximal of firing button stops 256 . The proximal movement of firing button 254 also places narrow flats 259 between firing button stops 256 . Releasing safety latch handle 249 allows safety latch torsion spring 251 to rotate safety latch 250 back towards the locked position with safety latch handle 249 forced against locked position safety latch stop 245 . With only narrow flats 259 and wide flats 261 between firing button stops 256 , safety latch 250 can freely rotate without interference from firing button stops 256 .
When firing button shaft 244 travels proximally, the roller 241 of firing button shaft 244 and cammed surface of firing latch 236 separate (see FIG. 15 ). Firing latch spring 246 then rotates firing latch 236 into a position where firing latch hook 238 is moved towards firing fork shaft 168 . An arming and firing cycle is now complete. Firing assembly 160 has returned to the post-fired position depicted in FIGS. 14 and 15.
It should be noted that if, after firing, the user of the firing mechanism 160 does not release firing button 254 before releasing safety latch handle 249 , the mechanism still operates properly because of incorporated unique design features. When firing button 254 is in the distal, pressed position, smaller firing button outer diameter 258 is between firing button stops 256 . Clearance for firing button stops 256 is made by alignment of firing button stops 256 with wide flats 261 . Releasing safety latch handle 249 before releasing firing button 254 causes safety latch torsion spring 251 to rotate safety latch 250 back towards the locked position and causes firing button stops 256 to rotate out of alignment with wide flats 261 . When the firing button stops 256 rotate out of alignment with wide flats 261 smaller firing button outer diameter 258 comes between firing button stops 256 . Smaller firing button outer diameter 258 is larger than the distance between firing button stops 256 . However, firing button stops 256 , designed to flex in the radial direction, separate by bending away from each other in the center when forced apart by smaller firing button outer diameter 258 . Because of the radial flexibility of firing stops 256 , firing button stops 256 apply little force to smaller firing button outer diameter 258 . With little force applied, firing button 254 slides easily through firing button stops 256 while returning to the proximal position. Firing button 254 returning to its proximal position brings smaller firing button outer diameter 258 between firing button stops 256 to allow safety latch 250 to continue to rotate back to the locked position. The difference in flexibility of the firing button stops radially and axially allows latching and release of triggering mechanism 235 regardless of order of operation of the components. Rigidity in the axial direction stops inadvertent operation of firing button 254 and flexibility in the radial direction allows interference with smaller firing button outer diameter 258 while still maintaining smooth release operation.
If desired, firing fork assembly 164 can be disassembled without tools from the rest of firing mechanism 160 and cleaned. Before a subsequent firing, an operator can attach a clean firing fork assembly 164 by mating proximal spade end 196 with spade slot 198 and threading firing spacer 188 onto end fitting 166 . When assembling firing fork assembly 164 with the firing mechanism in the post-fired position, an assembler can use depth marker line 189 to ensure proper assembly. The assembler can check alignment of depth marker line 189 with the outside surface of base shell 38 . A depth marker line 189 aligned with base shell 38 denotes a proper assembly. A depth marker line 189 that is misaligned with base shell 38 could indicate an improper assembly such as cross threading of firing spacer 188 or incomplete tightening of firing spacer 188 .
FIG. 22 shows an alternate embodiment of firing fork assembly 164 . Thumbscrew 191 threads into a threaded hole 187 on firing fork 62 . Threaded hole 187 on firing fork 62 passes through to a larger counter bore hole with flats on either side, commonly called a double-D hole 213 . Firing fork assembly 164 comprises thumbscrew 191 threaded onto firing fork 62 . Undercut 195 has an outer diameter less than the minor diameter of threaded hole 187 on firing fork 62 and thus maintains clearance between threaded hole 187 and undercut 195 . Thumbscrew 191 , after assembly to firing fork 62 , can thus turn freely on firing fork 62 utilizing the clearance between threaded hole 187 and undercut 195 . An alternate embodiment of firing fork shaft end fitting 166 , shown in FIG. 22, has end fitting flats 211 machined on either side of the second embodiment of end fitting 166 . End fitting 166 is welded to the distal end of firing fork shaft 168 . The configuration of end fitting 166 with end fitting flats 211 will accept double-D hole 213 of the alternate embodiment of firing fork 62 . Use of end fitting flats 211 with double-d hole 213 prevents rotation of firing fork 62 relative to end fitting 166 and firing fork shaft 168 . The alternate embodiment of firing fork assembly 164 threads into alternate embodiment of end fitting 166 which is welded onto firing fork shaft 168 . The alternate embodiment end fitting 166 has a threaded internal diameter 193 to accept the threaded proximal end of thumbscrew 191 . Thumbscrew 191 has a knurled, easily grasped surface so that the alternate embodiment of firing fork assembly 164 can be assembled and disassembled without the use of tools.
Dual four-bar mechanisms have been utilized in the present embodiment of the invention to facilitate ease of use by providing access by the user from either side of base 44 . A variation that would become evident to one skilled in the art after reading the description would be a single four-bar mechanism to create the firing mechanism.
While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims. | The present application is directed to an image-guided, vacuum assisted, percutaneous, coring, cable driven breast biopsy instrument which may be conveniently mounted to an x-ray machine wherein the biopsy instrument incorporates a rotation knob at the proximal end of the instrument to manually rotate the distal end of the probe, thus allowing the clinician to conveniently position the tissue port next to the tissue to be sampled. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to a headlight mounting and adjustment mechanism and, more particularly, to a device for adjusting the direction in which at least one headlight is aimed.
As is well known to those skilled in the art, it is important for automobile headlights to be aimed correctly. If they are aimed too high or to the left, the headlights might blind an oncoming driver and, this light blinding could, cause a serious automobile accident. However, an accident could occur even if the headlights are aimed too low or to the right, because, although the headlights may not blind an oncoming driver, the driver of the automobile will not be able to see objects at a distance ahead of him. Thus, incorrect aiming of the headlights reduces the driver's ability to see the road properly at night.
Accordingly, automobile headlights are required to have the capability of vertical and horizontal aiming adjustment not only for the automobile manufacturer's expediency, but also for the purpose of the occasional adjustment to be performed by the automobile user or a mechanic of an automobile repair station. In general, this headlight adjustment is effected to the headlight assemblies relative to a headlight support which may be a part of the automobile front body structure or a headlight housing which is fixedly attached to the front body structure.
In most automobiles, a headlight assembly comprises reflector having one or more lamps and a lens positioned frontwardly of the lamps, and the reflector is rigidly mounted on the headlight support, for example, the automobile front body structure, through a plurality of spaced bolt members thereby forming a device for the adjustment of the headlight direction and concurrently used to secure the reflector to the front body structure.
According to the prior art, the headlight adjustment is carried out by adjusting the extension of the bolt members, and the substantially simultaneous adjustment of some of the bolt members is required even when the headlight is desired to be adjusted correctly in only one direction. In this way, the prior art headlight adjustment mechanism requires a relatively complicated and time-consuming procedure for adjustment and, yet, this complicated and time-consuming procedure is often amplified in view of the fact that the adjustment of some of the bolt members causes a movement of the reflector in a direction diagonally of the vertical and horizontal directions.
SUMMARY OF THE INVENTION
Accordingly, the present invention has been developed so as to substantially eliminate the disadvantages and inconveniences inherent in the prior art headlight mounting and adjustment mechanisms and is intended to provide an improved adjusting device for the adjustment of the headlight direction, and the device is simple in construction and easy to operate because the headlight adjustment in both the vertical and horizontal directions can be effected substantially at one location which is adjacent the reflector.
Another important object of the present invention is to provide an improved device of the type referred to above, which device allows the headlight assembly to be easily installed relative to the headlight support because of the reduced number of fastening elements used to connect the headlight assembly to the headlight support as compared to the prior art.
A further object of the present invention is to provide an improved device of the type referred to above, which is relatively cheap to manufacture.
To this end, according to the present invention, at least one headlight assembly comprises a generally frustum-shaped, reflector having at least one lamp removably positioned therein in a manner known to those skilled in the art, and a pair of spaced mounting stays laterally outwardly protruding from the reflector of the construction described above is supported for adjustment relative to and by a headlight support, for example, a housing fixedly attached to an automobile front body structure in such a manner that one of the mounting stays is fixed to the reflector and is connected to the headlight support by a threaded connecting member while another or second mounting stay is elastically yieldingly connected to a sliding block. The sliding block is supported within a guide wall structure which is rigidly secured to the headlight support, and the slide block is supported for movement between front and rear positions within the guide wall structure. A horizontal adjustment bolt member threadably extends through the sliding block and is rotating but axially non-movably secured to the headlight support, so that, by rotating the horizontal adjusting bolt member in the appropriate direction, the sliding block can be moved between the front and rear positions for left-to-right or horizontal adjustment of the reflector. For the purpose of the up-and-down or vertical adjustment of the reflector, a vertical adjusting bolt member extends through the second mentioned mounting stay and is adjustably threaded into the sliding block for, when the vertical adjusting bolt member is turned in either direction, forcing the second mentioned mounting stay to pivot about the point of connection of the second mentioned mounting stay to the sliding block to tilt the reflector upwardly or downwardly.
Preferably, the mounting stays are oppositely positioned with respect to each other so that the headlight assembly can steadily be supported by the headlight support after the headlight adjustment has been performed.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and features of the present invention will become apparent from the following description taken in conjunction with a preferred embodiment thereof with reference to the accompanying drawings, in which:
FIG. 1 is a partially cutaway perspective view of a headlight mounting and adjustment mechanism according to the present invention with a reflector shown in phantom;
FIG. 2 is a longitudinal sectional view of an essential portion of the headlight mounting adjustment mechanism shown in FIG. 1, showing sliding block connected to a horizontal adjusting bolt member and one of the mounting stays for mounting the reflector; and
FIG. 3 is a longitudinal sectional view of a threaded connecting member used to secure the reflector to the headlight support.
DETAILED DESCRIPTION OF THE INVENTION
Before the description of the present invention proceeds, it is to be noted that like parts are designated by like reference numerals throughout the accompanying drawings.
Referring to the accompanying drawings, a headlight mounting and adjustment mechanism comprises a generally frustum-shaped reflector or headlight assembly 10, shown by the phantom lines, having a lamp or light 11 removably fixed at a location corresponding to or adjacent the apex of the frustum in any manner known to those skilled in the art. The reflector 10 is secured to a headlight support 12 in a manner as will be described in detail later, said headlight support 12 being shown in the form of a housing.
The reflector 10 has a pair of spaced mounting stays 13 and 14 laterally outwardly protruding from the reflector at a location corresponding to the base of the frustum. These mounting stays 13 and 14 are preferably positioned in opposition to each other and are welded to, or otherwise integrally formed with, the peripheral edge of the reflector 10 at a position adjacent the opening or base of the reflector 10. So far illustrated, the stay 13 is formed of a metal strip having one end fixed to the reflector 10 and the stay 13 is bent to assume; a substantially U-shaped configuration with the other end thereof protruding laterally towards the reflector 10. When the stay 13 of the shape described above and shown is utilized, the employment of any known welding technique is preferred for connecting the stay 13 to the reflector. However, when the stay 13 is formed with said other end thereof laterally protruding in a direction away from the reflector, the stay 13 may be either welded to the reflector 10 or formed integrally therewith.
The stay 13 is, as best shown in FIG. 3, mounted on a threaded connecting member 15 which has one end rotatably but axially non-movably connected to the stay 13, and the other end of the member 15 is threaded into and elastically yieldably received by an elastic bearing block 16 rigidly secured to the headlight support 12 in any known manner. One purpose of the elastic bearing block 16 is to permit the threaded connecting member 15 to tilt with respect to a vertical plane and a horizontal plane when the headlight adjustment mechanism is effected in a manner as will subsequently be described. It is to be noted that threading of the connecting member 15 into the elastic bearing block 16 can be accomplished by turning the connecting member 15 by the use of a screw driver engageable in a groove 15a formed at one end of the connecting member 15 opposite to the head portion thereof and remote from the stay 13. Alternatively, it may be possible to adjust the connecting member 15 by the use of a rod if the connecting member 15 is formed with a radially extending hole for receiving the rod.
The stay 14 opposite to the stay 13 has a pair of tongues 17 and 18, the tongue 17 extending in a direction generally parallel to the axis of the opening of the reflector 10 and parallel to the direction in which the headlight assembly is aimed, whereas the tongue 18 extends laterally outwardly from the reflector 10 and in a direction perpendicular to the direction in which the tongue 17 extends. The tongues 17 and 18 have a mounting aperture 17a and a generally U-shaped recess 18a respectively.
Positioned adjacent the stay 14 and operatively supported by the headlight support 12 is a generally rectangular sliding block 19. This sliding block 19 is housed within a generally elongated guide wall structure 20 for sliding movement between front and rear positions and has rib 19a and, as best shown in FIG. 2, a bearing projection 19b, both integrally formed therewith or otherwise rigidly connected thereto. The rib 19a laterally extends in a direction parallel to the direction of movement of the sliding block 19 and protrudes longitudinally outwardly from the sliding block toward the tongue 17. The bearing projection 19b extends longitudinally outwardly from the rib 19a in a direction perpendicular to the direction of movement of the sliding block 19. As best shown in FIG. 2, an elastic bushing 21 made of any suitable rubber material is mounted on the bearing projection 19b for the purpose as will become clear from the subsequent description, said elastic bushing 21 being held in position on the bearing projection 19b by a stop washer 22 which is mounted in any known manner on the bearing projection 19b on a side of the elastic bushing 21 remote from the slide block 19.
The guide wall structure 20 is rigidly secured at one end thereof to the headlight support 12 in any known manner, for example, by the use of a known welding technique or a known rivetting technique and longitudinally extends therefrom in a direction parallel to the direction in which the headlight assembly is aimed. This guide wall structure 20 is composed of a pair of opposed lateral side walls having a large space therebetween and a pair of opposed longitudinal side walls having a small space therebetween, the four walls being assembled to form the guide wall structure 20 so as to assume a generally rectangular cross section. In this guide wall structure 20, one of the longitudinal side walls facing the stay 14 is formed with a guide slot 20a extending in a direction parallel to the direction of movement of the slide block 19 between the front and rear positions.
While the guide wall structure 20 is constructed as hereinbefore described, the slide block 19 is movably housed within the guide wall structure 20 with the rib 19a accommodated in the guide slot 20a and with the bearing projection 19b protruding outwardly from the guide wall structure 20, as best shown in FIG. 2. The bearing projection 19b is inserted through the bearing aperture 17a in the tongue 17 in such a manner that the peripheral edges defining the bearing aperture 17a contact the elastic bushing 21 mounted on such bearing projection 19b. It is to be noted that the stop washer 22 is mounted on the bearing projection 19b after the bearing projection 19b has been inserted through the bearing or mounting aperture 17a in the tongue 17 with the elastic bushing 21 mounted either in the bearing aperture 17a or on the bearing projection 19b. The elastic bushing 21 serves to elastically yieldably connect the stay 14, specifically the tongue 17, to the sliding block 19 in order to accommodate the movement of the tongue 17 in a plane parallel to the longitudinal axis of the bearing projection 19b which may take place during the horizontal adjustment.
For the purpose of the horizontal adjustment, a horizontal adjusting bolt member 23 is employed. This adjusting bolt member 23 has a head portion 23a which is accessible by a screw driver and which extends threadingly through the sliding block 19, the free end of said adjusting bolt member 23 being rotably but axially non-movably connected to the headlight support 12 in a manner as best shown in FIG. 2. Because the sliding block 19 is confined within the guide wall structure 20, a turning of the adjusting bolt member 23 is either direction results in the movement of the sliding block 19 between the front and rear positions. This movement of the sliding block 19 is transmitted to the reflector 10 through the bearing projection 19b by way of the tongue 17 so that the direction in which the headlight assembly is aimed in a horizontal plane can be adjusted.
For the purpose of the vertical adjustment, a vertical adjusting bolt member 24 is employed. This adjusting bolt member 24 has a head portion 24a accessible by a screw driver, an end portion of the bolt member 24 adjacent the head portion 24a being engaged in the bearing recess 18a in the tongue 18. The engagement of that portion of the bolt member 24 in the bearing recess 18a is preferably such as to permit the rotation of the bolt member 24 about the longitudinal axis thereof but not the axial movement of the bolt member 24 relative to the tongue 18. However, in view of the employment of the elastic bearing block 16 which enables the threaded connecting member 15 to assume a tilted position relative to the headlight support 12, the peripheral edge portion of the tongue 18 defining the recess 18a can be held constantly in engagement with the head portion 24a of the bolt member 24 irrespective of the position of the headlight assembly in the horizontal plane.
The vertical adjusting bolt member 24 extends so as to be in parallel relation to the horizontal adjusting bolt member 23, and bolt member 24 has its free end portion adjustably threaded into the sliding block 19 as best shown in FIG. 1. It will readily be seen that, by turning the adjusting bolt member 24 in either direction, the tongue 18 of the stay 14 can be drawn towards or away from the sliding block 19 irrespective of the position of the sliding block 19, with the tongue 17 consequently rotating a certain angle about the longitudinal axis of the bearing projection 19b. Thus, the lighting direction of the headlight assembly in a vertical plane can be adjusted.
It is to be noted that the sliding block 19 may be made of any known rigid material, however, the use of a hard synthetic resin is preferred because of its light-weight and inexpensive features. It is also to be noted that, although the guide wall structure 20 has been described as having the guide slot 20a defined in one of the opposed, longitudinal side walls thereof, it may be constructed of a generally rectangular metallic plate by folding it so as to assume a generally C-shaped cross section with the spaced ends of the rectangular metallic plate defining the guide slot 20a. In addition, in order that the headlight assembly can steadily be supported relative to the headlight support 12, the stay 14, in opposition to the stay 13, is preferably located such that the tongues 17 and 18 thereof are positioned on respective sides of the imaginary center line or axis which divides the reflector 10 into upper and lower halves.
From the foregoing description of the present invention, it is now clear that, by turning the horizontal adjusting bolt member 23 causing the sliding block 19 to move between the front and rear positions along the horizontal adjusting bolt member 23, the reflector 10 can be pivoted in the horizontal plane about the point of connection of the threaded connecting member 15 to the elastic bearing block 16. On the other hand, by turning the vertical adjusting bolt member 24 varying the depth to which the vertical adjusting bolt member 24 is threadingly inserted into the sliding block 19, the stay 14 can be pivoted about the longitudinal axis of the bearing projection 19b thereby causing the reflector 10 to pivot in the vertical plane about an imaginary pivot line or axis between the point of connection of the threaded connecting member 15 to the elastic bearing block 16 and the point of pivot of the tongue 17 about the longitudinal axis of the bearing projection 19b. It is to be noted that the turning of the vertical adjusting bolt member 24 in either direction results in no substantial axial movement of the sliding block 19.
Although the present invention has fully been described in connection with the preferred embodiment thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications are apparent to those skilled in the art. For example, although the reflector 10 is shown as having an opening which is circumferentially generally rectangular in shape, it may have a generally circular shape. In addition, although the vertical adjusting bolt member 24 has been described and shown as being threadably engaged with the sliding block 19, it may extend either loosely through or completely clear of the slide block 19 and be threadably engaged with the headlight support 12 through an elastic bearing block similar to the block 16. When, as just described, the vertical adjusting bolt member 24 extends between the tongue 18 and the headlight support 12 clear of the sliding block 19, the sliding block 19 must have a lateral width smaller than that shown in FIG. 1 so as to form a clearance between one end face of the sliding block 19 and one of the longitudinal side walls of the guide wall structure 20 adjacent the vertical adjusting bolt member 24. Moreover, a compression spring may be mounted on the vertical adjusting bolt member 24 between the tongue 18 and the sliding block 19 or between the tongue 18 and the headlight support 12.
Any other changes and modifications are understood to be within the spirit and scope of the present invention unless they depart therefrom. | A headlight mounting and adjustment mechanism particularly suited for use in a motor vehicle for adjusting the direction in which the headlight is aimed includes a headlight assembly elastically yieldably supported by a headlight support at one location. A dual adjustment device is provided for effecting the up-and-down or vertical adjustment and also the left-to-right or horizontal adjustment of the headlight assembly. The dual adjustment device includes a sliding block supported for sliding movement between front and rear positions by a guide wall structure fixedly attached to the headlight support, and the sliding block has a bearing projection operatively and rotatably coupled to the headlight assembly, a horizontal adjusting bolt member threadingly extended through the slide block and received by the headlight support, and a vertical adjusting bolt member having one end coupled to the headlight assembly and the other end threadingly engaged with the sliding block or the headlight support so that by turning the vertical adjusting bolt member the up-and-down adjustment of the headlight assembly is achieved. | 1 |
FIELD OF THE INVENTION
The invention relates to a system and method for transferring a fluid between a container and an apparatus which uses the fluid. The invention particularly concerns a system and method for delivering liquid photographic processing chemicals from individual containers stored in separate compartments to a photographic processor apparatus and receiving effluent chemicals from the processor into emptied containers, while minimizing the possibility of delivering an incorrect liquid chemical from a container to the processor or receiving an effluent from the processor to a container holding fresh chemicals.
BACKGROUND OF THE INVENTION
Many types of equipment, such as photographic processor apparatus, require that a certain processing fluid be at least periodically delivered to the apparatus. Some such apparatus also require that effluent fluids be received from the apparatus. Photographic processor apparatus, in particular, require that liquid processing chemicals be added to the apparatus either to replenish liquids already in the apparatus or to provide a completely fresh batch of liquids to the apparatus. Similarly, spent or effluent processing chemicals must be received from the apparatus from time to time.
Various techniques are known for delivering liquid chemicals to photographic processors. Many involve the use of tanks where chemical concentrates are mixed with water. In other techniques, chemical concentrates are fed directly into the processor by a metering device and are mixed in the processor itself by the action of the pumps and filters. In the latter case, the chemical concentrates typically are supplied from cubitainers, drums, or bag-in-the-box containers.
At least two significant problems may occur when supplying chemicals to processors using either of these techniques. First, the known techniques provide quite an opportunity for spills and leaks. Second, the known techniques provide an opportunity for mixing or feeding the wrong chemicals into the processor or for delivering the chemicals improperly within the processor. In the latter regard, current processors known as minilabs have tanks in which the chemical concentrates are poured and then mixed with water. This provides an opportunity for several errors. The concentrates and water may be mixed incorrectly due to their being added to the tank in the wrong order. The wrong concentrates may be added. The wrong quantity of water may be added. The concentrates and water may be mixed in the wrong tank, such as bleach replenisher in the developer replenisher tank. There are currently no commercially available processors having features to prevent or substantially lessen the probability of such errors.
One attempt to solve the problem of adding the wrong chemical concentrates is to color code the bottles so they match the tanks into which they are to be poured in the processor. Another attempt has been to match the shape of the bottle to the shape of the inlet of the tank into which the bottle is to be placed. Even these methods leave a significant margin for error.
Accordingly a need has long been recognized for a system and method for transferring fluid between a container and an associated apparatus, while minimizing the possibility of delivering the wrong fluids to the apparatus.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a system and method for delivering a particular fluid to a photographic processor apparatus with minimal opportunity to misdeliver the fluid.
Still another object of the invention is to provide a system and method for delivering a fluid between a container and an apparatus for using the fluid, with minimal possibility for delivering the wrong fluid.
Yet another object of the invention is to provide a system that uses sensors and a microprocessor for ensuring delivery of the correct fluid between a container and an apparatus for using the fluid.
Our invention is defined by the claims. Our system is particularly suited for delivering fluid between at least one container for fluid and an associated apparatus for using fluid. The system may include at least one container for fluid; a first status code member associated with the container to indicate whether the container has been opened; a second status code member associated with the container to indicate whether or not the container has been emptied of a first fluid; and a third status code member associated with the container to indicate a type of the first fluid. To determine the condition of the status code members, our system also may include a first sensor associated with the apparatus to cooperate with the first status code member and produce a first signal indicative of an opened or unopened container; a second sensor associated with the apparatus to cooperate with the second status code member and produce a second signal indicative of a container emptied of a first fluid; and a third sensor associated with the apparatus to cooperate with the third status code member and produce a third signal indicative of a type of fluid. A controller is provided for receiving and processing the first to third signals to determine whether the proper container has been installed to deliver the first fluid to the apparatus.
Our system also may include a fourth status code member associated with the container to indicate whether the container has been refilled with a second fluid; a fourth sensor associated with the apparatus to cooperate with the fourth status code member and produce a fourth signal indicative of a container refilled with the second fluid; the controller also receiving and processing the fourth signal to determine whether the proper container has been installed to receive the second fluid from the apparatus.
The first, second and fourth status code members preferably are alterable; and our system may also include a first, selectively operable code change member associated with the apparatus for altering the first status code member from a closed container configuration to an opened container configuration; a second, selectively operable code change member associated with the apparatus for altering the second status code member from a full container configuration to an emptied container configuration; a third, selectively operable code change member associated with the apparatus for altering the fourth status code member from a container with the first fluid configuration to a container with the second fluid configuration. The first, second and third code change members are operatively connected to and selectively operable by the controller. In one embodiment of our system, each status code member may include a recess in the container and a puncturable membrane across the recess; each sensor may include a movable probe for engaging an intact membrane or entering the recess through a broken membrane; and each code change member may include a moveable piercer for breaking the membrane. In a preferred embodiment, the first fluids are liquid photoprocessing chemicals; the apparatus is a photographic processor; and the second fluids are spent chemicals from the processor.
Our method may include the steps of providing at least one container for photographic processor chemicals; providing a first status code member associated with the container to indicate whether the container has been opened; providing a second status code member associated with the container to indicate whether or not the container has been emptied of a first liquid; providing a third status code member associated with the container to indicate a type of the first liquid; sensing a condition of the first status code member and producing a first signal indicative of an opened or unopened container; sensing a condition of the second status code member and producing a second signal indicative of a container emptied of a first liquid; sensing a condition of the third status code member and producing a third signal indicative of a type of the first liquid; processing the first to third signals to determine whether a proper container has been sensed for delivery of the first liquid to the photoprocessor; and delivering the first liquid to the photoprocessor when the proper container has been sensed.
Our method also may include the steps of providing a fourth status code member associated with the container to indicate whether the container has been refilled with a second liquid from the photoprocessor; sensing a condition of the fourth status code member and producing a fourth signal indicative of a container for receipt of the second liquid from the photoprocessor; processing the fourth signal to determine whether a proper container has been sensed to receive the second liquid from the photoprocessor; and receiving the second liquid from the photoprocessor when the proper container has been sensed.
When the first, second and fourth status code members are alterable, our method also may include the steps of, after beginning the delivering step, altering the first status code member from a closed container configuration to an opened container configuration; after completing the delivering step, altering the second status code member from a full container configuration to an emptied container configuration; and after beginning the receiving step, altering the fourth status code member from a container with the first liquid configuration to a container with the second liquid configuration. When each status code member comprises a recess in the container and a puncturable membrane across the recess; each sensing step determines the status of the membrane; and each altering step punctures the membrane.
Accordingly, important advantageous effects of the present invention are that it provides an interface between a photographic processor apparatus and supply cartridge for fluid chemicals. The interface and a controller in the processor are effective to prevent a user from leaving a container installed at the wrong location in the processor; to identify a type of cartridge being used; and to signal the operator of the processor whether a cartridge is (i) full or partially full of fresh fluid, (ii) empty, or (iii) full or partially full of effluent from the processor. Another important advantageous effect of the system of the present invention is that the interface between the container and the processor communicates with the controller of the processor to prevent delivery of chemicals from an incorrect cartridge.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing as well as other objects, features and advantages of this invention will become more apparent from the appended Figures, wherein like reference numerals denote like elements, and wherein:
FIG. 1 shows a schematic side elevation view of a photographic processor apparatus of a general type in which the system and method of our invention may be used;
FIG. 2 shows a schematic end elevation view, partially broken away, from the right as viewed in FIG. 1;
FIG. 3 shows a perspective view, partially broken away, of a cartridge for liquid chemicals according to our invention;
FIG. 4 shows an exploded perspective view of the cartridge of FIG. 3;
FIG. 5 shows a fragmentary, exploded, perspective view of the interface between the cartridge and the processor;
FIG. 6 shows a schematic sectional view of one embodiment of the interface;
FIG. 7 shows a schematic, fragmentary, plan view of the interface of FIG. 5, just as the sensor probes of the processor are about to engage the cartridge;
FIG. 8 shows the apparatus of FIG. 7 after the cartridge has engaged fully with the processor and one sensor probe has been extended;
FIG. 9 shows a sectional view of the apparatus of FIG. 7 plus associated logic and control modules;
FIG. 10 shows a sectional view of the apparatus of FIG. 9, with a second sensor probe extended;
FIG. 11 shows a sectional view of the apparatus of FIG. 9 with a third sensor probe extended;
FIGS. 12 to 16 show various stages of use of the interface on the cartridge; and
FIG. 17 shows a flow chart of logic processing steps executed by the microprocessor of the photographic processor apparatus.
DETAILED DESCRIPTION OF THE INVENTION
The following is a detailed description of the preferred embodiments of the invention, reference being made to the drawings in which the same reference numerals identify the same elements of structure in each of the several Figures.
Referring to FIGS. 1 and 2, a photographic processor apparatus 10 is shown which may be provided with cartridges 12, 14 for delivery of fresh liquid chemicals to the processor and cartridges 16, 18 for receipt of spent chemical effluents from the processor. In the conventional manner, processor 10 includes, as shown in phantom lines, a developer tank 20, a bleach tank 22, a fix tank 24 and stabilizer tanks 26, 28, 30.
In the illustrated embodiment, each cartridge 12, 14 comprises one or more internal, flexible bags 32 and each cartridge is supported on a shelf 34. Flow of liquid from each flexible bag is controlled by a corresponding two-part valve 36 of the type shown in copending, commonly assigned U.S. patent application Ser. No. 08/220,984 filed 31 Mar. 1994 by Clark E. Harris and David L. Patton, the contents of which are hereby incorporated by reference. One part of each valve 36 is installed on the cartridge and the other, mating part is installed in the processor in position to mate with the first part when the cartridge is fully installed. Once the parts of valve 36 have mated, liquid is pumped from cartridge 14 by a replenishment pump 38 through a conduit 40. A recirculation pump 42 receives the output from pump 38 and discharges to a filter and heater assembly 44 through a conduit 46. From assembly 44, the liquid flows into an upper portion of tank 30 through a conduit 48. A conduit 50 at the bottom of tank 30 directs a portion of the contents of the tank back to pump 42 for recirculation and mixing. When replenishment pump is stopped, liquid can be recirculated continuously or intermittently through a circuit comprising recirculation pump 42, conduit 46, assembly 44, conduit 48, tank 30 and conduit 50. A similar liquid delivery system is provided for cartridge 12.
To ensure that the correct cartridge is connected to tanks 20 to 30, each cartridge 12, 14 includes an interface block 52 which mates with a corresponding sensor probe assembly 54 in the processor, preferably before the parts of valve 36 have mated. A programmable controller 56 for the processor receives signals from each probe assembly 54 over a cable 58. Beneath cartridges 12, 14, each cartridge 16, 18 also includes at least one flexible bag 60 for receiving effluents from the processor. Cartridges 16, 18 are installed on respective shelves 62. Each cartridge 16, 18 also comprises one part of a control valve assembly 64, the mating part of the valve being installed in the processor. An overflow conduit 66 leads from the bottom of each tank 20 to 30 to a corresponding valve assembly 64 to enable each cartridge 16, 18 to receive effluents. As in the case of cartridges 12, 14, an interface block 68 on cartridge each cartridge 16, 18 mates with a corresponding sensor probe assembly 70 in the processor, preferably before the parts of valve 64 have mated. A cable 72 delivers signals from each assembly 70 to controller 56. In the conventional manner, processor 10 also includes a photographic paper supply 74, a dryer 76 and a printer 78, which form no part of the present invention.
In operation of processor 10, a cartridge is placed on a shelf in the processor; so that, the interface block on the cartridge engages the sensor probe assembly in the processor, preferably before the parts of valve 36, 64 have mated. Controller 56 determines, using logic to be discussed later in this specification, whether the cartridge is the proper one to deliver fresh liquid to tanks 22 to 24 or to 26 to 28; or to receive effluent from the processor. A cartridge placed in the wrong location will cause the controller to signal the operator to remove and replace the cartridge. Once a cartridge of fresh liquid is properly placed and the parts of the corresponding control valves are mated, the controller actuates the corresponding probe assembly to alter a portion of the interface block to indicate that the cartridge has been opened. When a cartridge has been emptied of fresh liquid, the probe assembly alters another portion of the interface block to indicate that the cartridge is empty. Once a cartridge has been properly placed to receive effluent and has been filled, the corresponding probe assembly alters still another portion of the interface block to indicate that the cartridge is full of effluent. Thus, in accordance with our invention, the interface block and probe assembly cooperate to provide signals to the controller to indicate if a cartridge is full of fresh liquid, contains a particular fresh liquid, is partially full of fresh liquid, is empty or partially full of effluent, or is full of effluent.
FIGS. 3 and 4 show the overall arrangement of cartridges 12 to 18 for use in accordance with the principles of our invention. Each cartridge may comprise an outer rigid container 80, a closure portion 82 removably mounted to container 80, at least one flexible bag 32, 60 which holds the processing chemicals, and flow control valve 36, 64 connected to the flexible bag. Each control valve has a neck portion which securely engages one of a corresponding plurality of spaced openings 84 in closure portion 82. Interface blocks 52, 68 may be provided at one corner of closure 82, or at any convenient location on the closure. A plurality of status code members such as bores or recesses or openings 86 1 . . . 86 n , preferably four in number, are provided into block 52, 68 in any convenient pattern. Those skilled in the art will appreciate that the number of code members may be chosen to correspond with the number of characteristics of the cartridge to be monitored. As will be further discussed regarding FIGS. 12 to 16, when a cartridge is fresh and not yet inserted into a processor apparatus, a predetermined pattern of the code members 86 is closed by means such as a plastic membrane 88. In the illustrated embodiment, membrane 88 is shown to be transparent; however, this need not be.
The pattern of open and closed status code members thus can indicate the condition and contents of the cartridge. When a cartridge 12 to 18 is first placed on one of shelves 34, 62, interface block 52, 68 mates with the corresponding sensor probe assembly 54, 68 as shown progressively in FIGS. 5, 7 and 8. Initially, the sensor probe assembly simply senses the presence or absence of membrane 88 over each of status code elements 86. Whether membrane 88 is intact or punctured tells controller 56 the condition of the cartridge. For example, the presence of membrane 88 over element 86 1 would indicate an opened container of fresh liquid, while absence of the membrane would indicate a previously opened container. The presence of membrane 88 over element 86 2 would indicate a container not yet emptied of fresh liquid, while absence of the membrane would indicate a container emptied of fresh liquid. The presence of membrane 88 over element 86 3 would indicate a container not yet filled with effluent, while absence of the membrane would indicate a container filled with effluent. Finally, the presence of membrane 88 over element 86 4 would indicate a fill cartridge whose contents will be emptied to fill the processor, while absence of the membrane would indicate a run cartridge whose contents are used to replenish the processor. The membrane over element 864 typically would be punctured or left intact at the time the cartridge is originally filled.
As previously indicated, status code members 86 may be provided in a wide variety of patterns in addition to the simple linear array illustrated. Fewer or more status code members may be used. FIG. 7 shows schematically one type of switch and penetrator assembly 90 suitable for use in sensor probe assemblies 54, 70. A cover or support plate 92 is provided with a bore 94 within which a switch 96 is mounted. The switch is connected electrically to controller 56. An actuator plunger 98 extends axially from switch 96; so that, the plunger will make contact with membrane 88 when a cartridge is inserted and be forced into switch 96 to indicate the presence of the membrane. A support bracket or flange 100 positions switch 96. Slidably mounted in bore 94 and surrounding switch 96 is a cylindrical plunge knife 102, having an angled cutting edge 102 rather like an oversized hypodermic needle. An axially extending slot 106 in knife 102 allows passage of bracket 100 and permits the knife to move axially within the bore. An actuator 108, illustrated schematically, is connected mechanically to knife 102 and electrically to controller 56. When, knife 102 is extended, it punctures membrane 88 to alter the status code at that location.
FIGS. 5 to 7 show the interface block approaching the sensor probe assembly during installation of a cartridge. FIG. 17 illustrates the logic of operation of the system. Initially, plunge knives 102 would be withdrawn, as shown in FIG. 7. Assuming that a cartridge of fresh chemicals is being installed, FIG. 12 shows the condition of membrane 88 for a fill cartridge; and FIG. 13, for a run cartridge with the membrane removed over status element 86 4 . As the cartridge is installed, each of switch plungers 98 is forced toward its switch 96 to signal controller 56 that the membrane is present or absent. The controller will detect from the condition of the membrane at status element 86 4 that the cartridge is a fill or run cartridge. If the shelf should not receive that type of cartridge, the controller will signal the operator to remove and replace the cartridge. Note that no plunge knife is needed at location 86 4 , as shown schematically in FIGS. 5, 7 and 8. The controller will then check the condition of the membrane at status element 86 2 to detect from the condition of the membrane whether or not the cartridge has been emptied of fresh liquid. An emptied cartridge would exhibit membrane 88 as in FIG. 15 and would belong on one of shelves 62. A not yet emptied cartridge would exhibit membrane 88 as in FIGS. 12 to 14 and would belong on one of shelves 34. If necessary, the controller will signal the operator to remove and replace the cartridge. The controller will then check the condition of the membrane at status element of all four status elements to detect whether the cartridge is full as in FIGS. 12, 13 or 16; partially full as in FIG. 14; or either partially full or empty as in FIG. 15. A configuration of FIG. 15 will indicate a cartridge that is empty or partially filled with effluent and ready to receive effluent from the processor. A configuration of FIGS. 12 to 14 will indicate a cartridge that is full or partially full with fresh liquid and ready to deliver fresh liquid to the processor. A configuration of FIG. 16 will indicate a cartridge that is full of effluent and should be removed and replace.
When the processor is ready to receive fresh liquid from a full cartridge, as shown in FIG. 9, the controller actuates the plunge knife for location 86 1 , which then pierces the membrane to produce the configuration of FIG. 14. When the cartridge has been emptied, as shown in FIG.10, the controller actuates the plunge knife for location 86 2 to produce the configuration of FIG. 15. Conventional techniques, such as optical sensors or weighers, not illustrated, are used to detect an empty cartridge 12, 14.The cartridge is now ready for use to receive effluent. When a cartridge on one of shelves 62 is ready to receive effluent, the controller allows effluent to drain away to the cartridge. Conventional techniques, as previously mentioned, are used to detect a cartridge 16, 18 full of effluent. Once the cartridge is full of effluent, as shown in FIG. 11, the controller actuates the plunge knife at location 86 3 to produce the configuration of FIG. 16.
Parts List
10 . . . photographic processor apparatus
12, 14, 16, 18 . . . cartridges for liquid chemicals
20 . . . developer tank
22 . . . bleach tank
24 . . . fix tank
26, 28, 30 . . . stabilizer tanks
32 . . . flexible bag within 14, 16
34 . . . shelf for 14, 16
36 . . . flow control valve
38 . . . replenishment pump
40 . . . conduit
42 . . . recirculation pump
44 . . . filter and heater assembly
46 . . . conduit to 44 from 42
48 . . . conduit to top of 30 from 44
50 . . . conduit from bottom of 30 to 42
52 . . . interface block on 14, 16
54 . . . sensor probe assembly
56 . . . programmable controller for 10
58 . . . cable
60 . . . flexible bag within 18, 20
62 . . . shelf for 18
64 . . . flow control valve
66 . . . overflow conduit from 30 to 64
68 . . . interface block on 18, 20
70 . . . sensor probe assembly
72 . . . cable
74 . . . photographic paper supply
76 . . . dryer
78 . . . printer
80 . . . outer rigid container
82 . . . closure
84 . . . openings in 82
86 1 . . . 86 n . . . status code bores in 52, 68
88 . . . membrane over 86 1 . . . 86 n
90 . . . switch and penetrator assembly
92 . . . cover plate
94 . . . bore
96 . . . switch
98 . . . plunger to engage
100 . . . support bracket
102 . . . cylindrical plunge knife
104 . . . angled cutting edge
106 . . . slot in 102
108 . . . actuator for 102
110 . . . logic and control module
Our invention has therefore been described with reference to certain embodiments thereof, but it will be understood by persons skilled in the art that variations and modifications can be effected without departing from the scope of our invention. | A system and method are taught for transferring fluids between a container and an associated apparatus for using the fluid. Interface members (52, 68; 86, 88) on the container (80, 82) cooperate with sensor probe assemblies (54, 70; 90-108) and a controller (56) in the associated apparatus to indicate the status of the container as full or partially full of fresh liquid, emptied of fresh liquid, or full or partially full of effluent liquid. The likelihood of delivering the wrong liquid to the associated apparatus is minimized. The invention is particularly useful for delivery of liquid chemicals to a photographic processor apparatus. | 6 |
FIELD OF THE INVENTION
[0001] This invention generally relates to display illumination articles for enhancing luminance from a surface and more particularly relates to a turning film having multiple slopes that redirects light from a light guiding plate.
BACKGROUND OF THE INVENTION
[0002] Liquid crystal displays (LCDs) continue to improve in cost and performance, becoming a preferred display type for many computer, instrumentation, and entertainment applications. The transmissive LCD used in conventional laptop computer displays is a type of backlit display, having a light providing surface positioned behind the LCD for directing light outwards, towards the LCD. The challenge of providing a suitable backlight apparatus having brightness that is sufficiently uniform while remaining compact and low cost has been addressed following one of two basic approaches. In the first approach, a light-providing surface is used to provide a highly scattered, essentially Lambertian light distribution, having an essentially constant luminance over a broad range of angles. Following this first approach, with the goal of increasing on-axis and near-axis luminance, a number of brightness enhancement films have been proposed for redirecting a portion of this light having Lambertian distribution in order to provide a more collimated illumination.
[0003] A second approach to providing backlight illumination employs a light guiding plate (LGP) that accepts incident light from a lamp or other light source disposed at the side and guides this light internally using Total Internal Reflection (TIR) so that light is emitted from the LGP over a narrow range of angles. The output light from the LGP is typically at a fairly steep angle with respect to normal, such as 70 degrees or more. With this second approach, a turning film, one type of light redirecting article, is then used to redirect the emitted light output from the LGP toward normal. Directional turning films, broadly termed light-redirecting articles or light-redirecting films, such as that provided with the HSOT (Highly Scattering Optical Transmission) light guide panel available from Clarex, Inc., Baldwin, N.Y., provide an improved solution for providing a uniform backlight of this type, without the need for diffusion films or for dot printing in manufacture. HSOT light guide panels and other types of directional turning films use arrays of prism structures, in various combinations, to redirect light from a light guiding plate toward normal, or toward some other suitable target angle that is typically near normal relative to the two-dimensional surface. As one example, U.S. Pat. No. 6,746,130 (Ohkawa) describes a light control sheet that acts as a turning film for LGP illumination.
[0004] Referring to FIG. 1 , the overall function of a light guiding plate 10 in a display apparatus 100 is shown. Light from a light source 12 is incident at an input surface 18 and passes into light guiding plate 10 , which is typically wedge-shaped as shown. The light propagates within light guiding plate 10 until Total Internal Reflection (TIR) conditions are frustrated and then, possibly reflected from a reflective surface 142 , exits light guiding plate at an output surface 16 . This light then goes to a turning film 20 and is directed to illuminate a light-gating device 120 such as an LCD or other type of spatial light modulator or other two-dimensional backlit component that modulates the light. For optimized viewing under most conditions, the emitted light should be provided over a range of relatively narrow angles about a normal V. A polarizer 124 is typically disposed in the illumination path in order to provide light-gating device 120 such as a liquid crystal cell with suitably polarized light for modulation. A reflective polarizer 125 may be provided between absorptive polarizer 124 and turning film 20 .
[0005] Referring to FIG. 2 , there is shown a schematic cross-sectional view of a conventional turning film 20 a used with light guiding plate 10 , showing key angles and geometric relationships. Turning film 20 a has a number of prismatic structures facing downward toward light guiding plate 10 , each structure having a near surface 24 (being near relative to light source 12 , as shown in the embodiment of FIG. 1 ) and a far surface 26 , both sides slanted from a film normal direction V as determined by an apex angle α, and base angles β 1 and β 2 , relative to a horizontal S. Light from light guiding plate 10 is incident over a small range of angles about a central input angle θ in . The output angle θ out of light delivered to the LC display element is determined by a number of factors including the central input angle θ in , the refractive index n of turning film 20 a , and the base angle β 1 at which far surface 26 is slanted. Output angle θ out for emitted light is preferably normal with respect to turning film 20 a , however output angle θ out can be considered a target angle, which may be at some inclination with respect to normal for some applications. For most conventional turning films, the target angle is near normal. In a typical arrangement, base angles β 1 and β 2 are about 56 degrees, and apex angle α, 68 degrees. The primary (or principal) ray 50 a having an input angle around θ in ≈70° is redirected to near normal direction. However, some secondary rays 50 c , 50 c 1 having an input angle around θ in <70° may take paths as shown in FIG. 2 . Secondary ray 50 c 1 is redirected toward a relative large angle from the normal direction. Further, secondary ray 50 c is totally reflected back by the light exiting surface 92 . Consequently, the light utilization of this existing turning film is not satisfactory.
[0006] Referring to FIG. 3 , there is shown a schematic cross-sectional view of an improved turning film 90 a having multiple slopes. The turning film 90 a , while improving the light utilization, has base angle β 1 generally less than 90°. Moreover, during the manufacture of the turning film 90 a , it may be difficult to precisely control the base angle β 1 due to the asymmetry of the turning film 90 a . Thus, while there have been solutions proposed for turning films suitable for some types of display apparatus and applications, there remains a need for improved turning films.
SUMMARY OF THE INVENTION
[0007] The present invention provides a light redirecting article for redirecting light toward a target angle, the light redirecting article comprising: (a) an input surface comprising a plurality of light redirecting structures each light redirecting structure having: (i) a near surface having two slopes, sloping away from normal in one direction as defined by a first inclination base angle β 1 , a second inclination angle β 2 , and a first half apex angle α 2 , for accepting incident illumination over a range of incident angles; (ii) a far surface sloping away from normal, in the opposite direction relative to the input surface, as defined by a second base angle γ 1 and a second half apex angle α 1 ; and (b) an output surface opposing to the input surface, wherein the near and far surfaces are opposed to each other at an angle (α 1 +α 2 ), and the base angle β 1 is greater than or equal to 90 degrees.
[0008] The present invention also provides a light redirecting article for redirecting light toward a target angle, the light redirecting article comprising: (a) an input surface comprising a plurality of light redirecting structures, each light redirecting structure having: (i) a near surface having two slopes, sloping away from normal in one direction as defined by a first inclination base angle β 1 , a second inclination angle β 2 , and a first half apex angle α 2 , for accepting incident illumination over a range of incident angles; (ii) a far surface sloping away from normal, in the opposite direction relative to the input surface, as defined by a second base angle γ 1 and a second half apex angle α 1 ; and (b) an output surface opposing to the input surface, wherein the near and far surfaces are opposed to each other at an angle (α 1 +α 2 ), two neighboring light redirecting structures have a gap G and a pitch P, and G/P is in the range of between about 0.08 and 0.12.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a cross sectional view showing components of a conventional display apparatus;
[0010] FIG. 2 is a schematic cross-sectional view showing a turning film with prismatic structure facing downward, toward the light guiding plate;
[0011] FIG. 3 is a schematic cross-sectional view showing a single unit of a prior turning film having two slopes on the near surface of the prismatic structures with a base angle less than 90°;
[0012] FIG. 4A is a schematic cross-sectional view showing two units of a turning film having a base angle equal to or greater than 90° according to the present invention;
[0013] FIG. 4B is a schematic cross-sectional view showing two unit of a turning film having a gap G according to the present invention;
[0014] FIG. 5 is a schematic cross-sectional view showing a turning film of the present invention in an LCD display system;
[0015] FIG. 6A is a schematic top view showing an LCD with a pair of polarizers oriented at 45 degrees relative to the grooves of the light redirecting structure of the turning film;
[0016] FIG. 6B is a schematic top view showing an LCD with a pair of polarizers oriented at parallel or perpendicular to the grooves of the light redirecting structure of the turning film; and
[0017] FIG. 6C is a schematic top view showing a turning film with arcuate grooves.
DETAILED DESCRIPTION OF THE INVENTION
[0018] The apparatus of the present invention uses light-redirecting structures that are generally shaped as prisms. True prisms have at least two planar faces. Because, however, one or more surfaces of the light-redirecting structures need not be planar in all embodiments, but may be curved or have multiple sections, the more general term “light redirecting structure” is used in this specification.
[0019] FIG. 3 shows one unit of a turning film 90 a , which comprises a substrate 96 having a light inputting surface 94 and a light exiting surface 92 . On the side of the light inputting surface 94 of the film 90 a is a prismatic structure which is described by points P 1 , P 2 , P 3 , and P 4 and characterized by a near surface 24 and a far surface 26 , and the near surface is composed of at least first flat segment 24 a and second flat segment 24 b , the angle β 2 between the first segment 24 a and the horizontal direction S is smaller than the angle β 1 between the second segment 24 b and the horizontal direction S. The prismatic structure can be further described by two half apex angles α 1 and α 2 , the pitch P and height H, and three projection dimensions L 1 , L 2 , and L 3 . The prismatic structure is made of a material of refractive index n, and the substrate may have its index of refraction greater than, equal to, or less than n. The shape and the refractive index n of the prismatic structure are chosen so that the primary ray 50 a from the light guide plate 10 , secondary ray 50 b having larger incident angle than the primary ray 50 a , and secondary ray 50 c having smaller incident angle than the primary ray 50 a are characterized as following: the primary ray 50 a is refracted by the first segment 24 a of the near surface 24 , subsequently reflected due to the total internal reflection at the far surface 26 , and finally emerges out toward the target angle (normally within 5 degrees from the normal of the film); the secondary ray 50 b is also refracted by the first segment 24 a of the near surface 24 , subsequently reflected due to the total internal reflection at the far surface 26 , and finally emerges out in a direction that is bent more from its original direction than the primary ray 50 a ; and the secondary ray 50 c is refracted by the second segment 24 b of the near surface 24 , subsequently reflected due to the total internal reflection at the far surface 26 , and finally emerges out in a direction that is closer to the target direction than it would if the second segment 24 b has the same slope as the first segment 24 a.
[0020] FIG. 4A shows two neighboring units of a turning film 90 b according to the present invention, which comprises a substrate 96 having a light inputting surface 94 and a light exiting surface 92 . On the side of the light inputting surface 94 of the film 90 b is a prismatic structure which is described by points P 1 , P 2 , P 3 , and P 4 for one unit and points P 1 ′, P 2 ′, P 3 ′, and P 4 ′ for another unit, and characterized by a near surface 24 and a far surface 26 , and the near surface is composed of at least first flat segment 24 a and second flat segment 24 b , the angle β 2 between the first segment 24 a and the horizontal direction S is smaller than the angle β 1 between the second segment 24 b and the horizontal direction S. The prismatic structure can be further described by two half apex angles α 1 and α 2 , the pitch P and height H, and three projection dimensions L 1 , L 2 , and L 3 . The prismatic structure is made of a material of refractive index n, and the substrate may have its index of refraction greater than, equal to, or less than n. The shape and the refractive index n of the prismatic structure are chosen so that the primary ray 50 a from the light guide plate 10 , secondary ray 50 b having larger incident angle than the primary ray, and secondary ray 50 c having smaller incident angle than the primary ray have similar characteristics as the turning film 90 a shown in FIG. 3 .
[0021] According to one aspect of the present invention, the improved turning film 90 b has a near based angle β 1 ≧90°. Note that in FIG. 4A , the based angle β 1 is sharp, but it can also be rounded, meaning that there may be a curvature near Points P 1 ′ and P 1 .
[0022] According to another aspect of the present invention, the improved turning film 90 b has a gap G between the base points P 4 ′, P 1 of two neighboring prisms. As a result, projection dimension L 1 is negative as it is the difference between the projected coordinates onto the horizontal direction S of two neighboring points of one prism, while keeping L 1 /P+L 2 /P+L 3 /P=1.
[0023] Inventive (denoted as “I”) and comparative examples (denoted as “C”) of turning film 90 b are shown in Table 1-Table 2. In all of these examples, refractive index n is held constant at 1.5, and pitch P of the prisms is about 50 μm, though it can be in the range of 15 to 150 μm, preferably in the range of 20 to 75 μm, more preferably in the range of 25 to 50 μm. When n and P are held constant, there are 4 independent parameters to specify the shape of turning film 90 b , which are chosen to be L 1 /P, L 2 /P, β 1 , and β 2 . The height H and angles can be calculated as
[0000]
H
=
P
[
l
1
tan
(
β
1
)
+
l
2
tan
(
β
2
)
]
,
α
1
=
tan
-
1
(
1
-
l
1
-
l
2
h
)
,
α
2
=
90
°
-
β
2
α
≡
α
1
+
α
2
γ
1
=
90
°
-
α
1
,
where
l
1
≡
L
1
P
,
l
2
≡
L
2
P
,
h
≡
H
P
.
[0000] When α 1 =α 2 , it follows
[0000]
l
2
=
1
-
l
1
2
-
l
1
2
tan
(
β
1
)
tan
(
β
2
)
,
or
l
1
=
1
-
2
l
2
1
+
tan
(
β
1
)
tan
(
β
2
)
.
[0000] Consistent with the above discussion, when β 1 =90°,
[0000]
l
1
≡
L
1
P
=
0
;
[0000] and when β 1 ≧90°,
[0000]
l
1
≡
L
1
P
<
0.
[0024] In Table 1-2, Columns L 1 /P, β 1 , and β 2 are independent parameters. L 2 /P is chosen to be
[0000]
L
2
/
P
=
l
2
=
1
-
l
1
2
-
l
1
2
tan
(
β
1
)
tan
(
β
2
)
[0000] to ensure α 1 =α 2 =90°−β 2 , and α≡2α 1 . The four right most columns represent the output of turning film in terms of total power, maximum intensity ratio, maximum intensity angle, and on-axis intensity ratio. The turning film of the present invention has: Power ≧85%, Maximum intensity ratio ≧1.1 and Maximum intensity angle is within −5° and −5°.
[0000]
TABLE 1
summarizes impact of β 1 and G/P when β 1 ≧ 90°.
Maximum
Maximum
On-axis
β 1
Intensity
Intensity
Intensity
Ex
L 1 /P
L 2 /P
(°)
G/P
Power
Ratio
angle (°)
ratio
C1.1
−0.36029
0.25498
105.9
0.32
0.870
0.810
3.5
0.699
C1.2
−0.32143
0.24770
104.7
0.3
0.881
0.859
1.5
0.766
C1.3
−0.28472
0.24082
103.4
0.28
0.888
0.937
2.5
0.846
C1.4
−0.25000
0.23431
102.2
0.26
0.893
0.990
1.5
0.950
C1.5
−0.21711
0.22814
100.9
0.24
0.895
1.013
0.5
1.012
C1.6
−0.18590
0.22229
99.6
0.22
0.896
1.066
−0.5
1.046
C1.7
−0.15625
0.21673
98.3
0.2
0.895
1.081
−0.5
1.080
I1.1
−0.12805
0.21145
97.0
0.18
0.895
1.114
0.5
1.105
I1.2
−0.10119
0.20641
95.7
0.16
0.895
1.124
1.5
1.110
I1.3
−0.07558
0.20161
94.3
0.14
0.894
1.129
1.5
1.117
I1.4
−0.05114
0.19703
93.0
0.12
0.894
1.157
1.5
1.132
I1.5
−0.02778
0.19265
91.7
0.1
0.894
1.157
1.5
1.137
I1.6
−0.00543
0.18846
90.3
0.08
0.893
1.167
1.5
1.146
C1.8
0.01596
0.18445
89.0
0.06
0.893
1.189
1.5
1.157
C1.9
0.03646
0.18061
87.7
0.04
0.892
1.173
1.5
1.134
C1.10
0.05612
0.17693
86.3
0.02
0.892
1.168
1.5
1.161
C1.11
0.07500
0.17339
85.0
0
0.892
1.196
1.5
1.155
[0025] In Table 1, Ex. C1.1-C1.7, C1.8-C.11 and I1.1-I1.6 show the impact of β 1 , L 1 /P, L 2 /P, and Gap/P, given α 1 =α 2 =α=34°, and β 2 =56°. Turning films of inventive examples I1.1 through I1.6 all have β 1 ≧90° and meet the criteria: high power (>0.88), large maximum peak intensity ratio (≧1.10), and small maximum intensity angle from the normal (≦±5°). When β 1 is out of the preferred range between 90° and 98°, or Gap/P is out of the preferred range of between 0.19 and 0.07, the outputs from comparative examples C1.1-C1.7 do not meet all of the criteria, in terms of power (>0.85), maximum intensity ratio (≧1.10), and maximum intensity angle (≦±5°, indicating inferior performance.
[0026] Compared to comparative examples C1.8-C1.11 which have either G/P=0, or G/P out of the preferred range, the present invention of examples I1.1-I1.6 may be easier for manufacturing due to the existence of the gap between the base points P 4 , P 4 ′ (or P 1 , P 1 ′) of two neighboring prisms, and/or the base angle β 1 ≧90°.
[0000]
TABLE 2
summarizes impact of G/P when β 1 ≧ 90°.
Maximum
Maximum
On-axis
Intensity
Intensity
Intensity
Ex
G/P
Power
Ratio
angle (°)
ratio
I2.1
0.00000
0.899
1.119
2.5
1.062
I2.2
0.01961
0.899
1.112
1.5
1.073
I2.3
0.03846
0.898
1.107
3.5
1.061
I2.4
0.05660
0.897
1.130
1.5
1.061
I2.5
0.07407
0.897
1.137
1.5
1.090
I2.6
0.09091
0.897
1.154
2.5
1.108
I2.7
0.10714
0.895
1.153
2.5
1.110
I2.8
0.12281
0.897
1.154
0.5
1.133
I2.9
0.13793
0.894
1.131
1.5
1.095
I2.10
0.15254
0.896
1.121
1.5
1.108
I2.11
0.16667
0.894
1.112
0.5
1.101
I2.12
0.18033
0.895
1.131
1.5
1.118
I2.13
0.19355
0.895
1.129
−0.5
1.125
I2.14
0.20635
0.894
1.144
0.5
1.128
I2.15
0.21875
0.893
1.133
−0.5
1.125
I2.16
0.23077
0.893
1.115
−0.5
1.093
I2.17
0.24242
0.893
1.118
−0.5
1.095
C2.1
0.25373
0.894
1.090
−0.5
1.063
C2.2
0.26471
0.894
1.093
−1.5
1.045
C2.3
0.27536
0.893
1.089
−1.5
1.059
C2.4
0.28571
0.893
1.086
−2.5
1.016
[0027] Table 2 shows the impact of G/P when the other parameters are kept constant; L 1 /(P−G)=−0.10119, L 2 /(P−G)=0.20641, β 1 =95.7°, β 2 =56°, α 1 =α 2 =α=34°, and n=1.5. The shape of the prisms specified by those parameters is identical to example I1.2 in Table 1.
[0028] Turning films of inventive examples I2.1-I2.17 meet the criteria: high power (>0.88), large maximum peak intensity ratio (≧1.10), and small maximum intensity angle from the normal (≦±5°), while comparative examples C2.1-C2.4 do not. Note that the maximum intensity ratio first decreases with G/P, then increases with G/P. The maximum intensity ratio reaches a local maximum value of about 1.15 when G/P is in the range of between about 0.08 and 0.12. As G/P further increases, the maximum intensity ratio decreases and then increases to a second local maximum value of about 1.14 when G/P is about 0.21. When G/P is greater than about 0.25, the maximum intensity ratio becomes below than 1.10, as shown in examples C2.1-C2.4.
[0029] Thus, Table 2 shows a turning film according to the present invention having a selective G/P ratio to maximize the maximum intensity ratio while allowing easy manufacture.
[0030] Though the preferred G/P range of between about 0.08 and 0.12 is found for a turning film 90 b having a base angle β 1 ≧90°, applicants find that this G/P range also works well for a turning film 90 c having a base angle β 1 <90°. FIG. 4B is a schematic cross-sectional view showing two neighboring units of a turning film 90 c having two slopes on the near surface of the prismatic structures and the based angle β 1 <90° and a gap G according to the present invention. Like parts in FIGS. 3 , 4 A and 4 B are designated by the same parts number.
[0000]
TABLE 3
summarizes impact of G/P when β 1 < 90°.
Maximum
Maximum
On-axis
Intensity
Intensity
Intensity
Ex
G/P
Power
Ratio
angle (°)
ratio
I3.1
0.0099
0.892
1.204
0.5
1.177
I3.2
0.0291
0.891
1.173
1.5
1.165
I3.3
0.0476
0.889
1.185
1.5
1.169
I3.4
0.0654
0.890
1.178
0.5
1.175
I3.5
0.0826
0.889
1.189
−0.5
1.175
I3.6
0.0991
0.888
1.172
−0.5
1.162
I3.7
0.1071
0.888
1.199
0.5
1.193
I3.8
0.1150
0.888
1.179
−0.5
1.170
I3.9
0.1228
0.887
1.188
−1.5
1.182
I3.10
0.1379
0.886
1.153
−1.5
1.134
I3.11
0.1453
0.887
1.158
−0.5
1.147
I3.12
0.1525
0.886
1.168
−1.5
1.124
I3.13
0.1597
0.885
1.165
−1.5
1.120
I3.14
0.1667
0.886
1.166
−1.5
1.116
I3.15
0.1736
0.887
1.169
−1.5
1.109
I3.16
0.1803
0.886
1.162
−1.5
1.123
I3.17
0.1870
0.885
1.148
−1.5
1.127
I3.18
0.1935
0.886
1.141
−2.5
1.105
I3.19
0.2000
0.884
1.130
−0.5
1.120
I3.20
0.2063
0.885
1.170
−2.5
1.100
I3.21
0.2126
0.886
1.140
−1.5
1.119
I3.22
0.2188
0.884
1.140
−2.5
1.084
I3.23
0.2248
0.885
1.114
−2.5
1.064
I3.24
0.2308
0.884
1.157
−2.5
1.105
I3.25
0.2366
0.884
1.128
−2.5
1.066
I3.26
0.2424
0.885
1.147
−2.5
1.045
I3.27
0.2481
0.882
1.134
−1.5
1.072
I3.28
0.2537
0.885
1.160
−2.5
1.073
I3.29
0.2593
0.882
1.118
−2.5
1.075
I3.30
0.2647
0.885
1.130
−2.5
1.080
I3.31
0.2701
0.883
1.143
−2.5
1.096
I3.32
0.2754
0.884
1.116
−3.5
1.063
I3.33
0.2857
0.885
1.113
−1.5
1.037
I3.34
0.2908
0.883
1.115
−2.5
1.035
I3.35
0.2958
0.885
1.112
−2.5
1.066
I3.36
0.3007
0.883
1.110
−3.5
1.045
C3.1
0.3056
0.885
1.098
−1.5
1.016
C3.2
0.3377
0.882
1.077
−2.5
0.989
C3.3
0.3421
0.883
1.096
−2.5
0.978
C3.4
0.4737
0.881
1.002
−6.5
0.788
[0031] Table 3 shows the impact of G/P when the other parameters are kept constant; L 1 /(P−G)=0.077, L 2 /(P−G)=0.16633, β 1 =85°, β 2 =56°, α 1 =α 2 =α=34°, and n=1.5. The shape of the prism specified by L 1 /(P−G)=0.077, L 2 /(P−G)=0.16633, β 1 =85°, β 2 =56°, α 1 =α 2 =α=34°, and n=1.5.
[0032] The inventive examples I3.1-I3.36 meet the criteria: high power (>0.88), large maximum peak intensity ratio (≧1.10), and small maximum intensity angle from the normal (≦±5°). When the ratio of gap over the pitch G/P is out of the preferred range of between 0 and 0.3, the outputs from comparative examples C3.1-C3.4 do not meet all of the criteria, in terms of power (>0.85), maximum intensity ratio (≧1.10), and maximum intensity angle (≦±5°), indicating inferior performance.
[0033] Examples I3.3-I3.9 in Table 3 also show a more preferred range for G/P is between 0.08 and 0.12. In this range, the turning film of the present invention is easy to fabricate, and also has reasonably good optical performance as shown by the large maximum peak intensity ratio greater than 1.17.
Display Apparatus and Orientation of Polarizers
[0034] The apparatus and method of the present invention allow a number of possible configurations for support components to provide light for an LCD. FIG. 5 is a schematic cross-sectional view showing a display apparatus 60 using turning film 90 , which can be 90 b or 90 c according to the present invention. An LC spatial light modulator 70 modulates light received from light guiding plate 10 and turning film 90 . A back polarizer 72 and a front polarizer 73 are provided for LC spatial light modulator 70 .
[0035] FIG. 6A is a schematic top view showing polarized light transmission axes 172 and 173 for LC spatial light modulator 70 , using a pair of polarizers that are oriented at 45 degrees relative to light redirecting structures 75 and grooves of turning film 90 that extend vertically in the view of FIG. 6A . In this case, the LC spatial light modulator 70 can be a twisted nematic (TN) LCD, which is the dominant mode used in a notebook and monitor display.
[0036] FIG. 6B is a schematic top view showing polarized light transmission axes 172 and 173 for LC spatial light modulator 70 , using a pair of polarizers oriented at parallel or perpendicular relative to the grooves and light redirecting structures 75 of turning film 90 . In this case, the LC spatial light modulator 70 can use vertically aligned (VA) LCD or IPS LC elements. Rear polarizer transmission axis 172 is parallel to the plane of the cross section.
[0037] In one embodiment the display apparatus comprises a pair of crossed polarizers, wherein the light redirecting structures are elongated in an elongation direction and wherein each of the crossed polarizers is oriented either substantially parallel or perpendicular to the elongation direction of the light redirecting article. In another embodiment the display apparatus comprises a pair of crossed polarizers, wherein the light redirecting structures are elongated in an elongation direction and wherein the polarizers are substantially oriented at ±45 degrees relative to the elongation direction of the light redirecting article.
[0038] FIG. 6C is a schematic top view showing turning film 90 with arcuately elongated light redirecting structures 75 in another embodiment. This arrangement is advantageous for employing a point light source such as Light Emitting Diode (LED) at one or more corners of light guiding plate 10 in order to have a more compact design. The rear polarizer transmission axis 172 is more or less parallel to the plane of the cross section.
Materials for Forming Turning Film
[0039] Turning film 90 b - 90 c of the present invention can be fabricated using polymeric materials having indices of refraction ranging typically from about 1.40 to about 1.66. Possible polymer compositions include, but are not limited to: poly(methyl methacrylate)s, poly(cyclo olefin)s, polycarbonates, polysulfones and various co-polymers comprising various combinations of acrylate, alicyclic acrylate, carbonate, styrenic, sulfone and other moieties that are known to impart desirable optical properties, particularly high transmittance in the visible range and low level of haze. Various miscible blends of the aforementioned polymers are also possible material combinations that can be used in the present invention. The polymer compositions may be either thermoplastic or thermosetting. The former are manufacturable by an appropriate melt process that requires good melt processability while the latter can be fabricated by an appropriate UV cast and cure process or a thermal cure process.
[0040] Turning film 90 b - 90 c of the present invention may be fabricated using materials having an index of refraction in the range of 1.12 and 1.40. Example materials are inorganic materials, for example, MgF. Also, materials having a grating formed between a common polymeric material having refractive index in the range of 1.48 and 1.59 and air (n=1). Further, a mix of low index materials (n<1.4) and materials having indices of refraction from about 1.40 to 1.50 may be used as well.
Maximum Intensity Ratio (or Optical Gain), Maximum Intensity Angle (or Peak Angle), and Power of a Turning Film
[0041] In general, light distribution is specified in terms of spatial and angular distributions. The spatial distribution of light can be made quite uniform, achieved by careful placement of micro features on top and/or bottom sides of a light guide plate. The angular distribution of light is specified in terms of luminous intensity I as a function of polar angle θ and azimuthal angle. The angular distribution of light is measured with EZ Contrast 160 (available from Eldim, France). Polar angle θ is the angle between the light direction and the normal of the light guide plate V. The azimuthal angle is the angle between the projection of the light onto a plane that is perpendicular to the normal direction V and a direction that is parallel to the length direction of the light guide plate. The length direction of the light guide plate is perpendicular to the light source 12 and the normal direction V. The angular distribution of light can also be specified in terms of luminance L as a function of polar angle θ and azimuthal angle. The luminance L and the luminous intensity I are related by L=I/cos(θ).
[0042] The maximum intensity angle, also referred as peak angle of a light distribution is defined as the polar angle at which the maximum luminous intensity occurs. Each luminous intensity distribution then defines a maximum (or peak) luminous intensity and a maximum intensity (or peak) angle.
[0043] The maximum intensity ratio, also referred as optical gain, or normalized peak intensity, of a turning film, is defined as a ratio of the maximum luminous intensity of the light that is transmitted through the turning film over the maximum luminous intensity of the light that is emitted from a light guide plate. As a result, the maximum intensity ratio of a turning film is not dependent upon the absolute level of the light source, but is primarily dependent upon the turning film design itself.
[0044] The power of a turning film is the ratio of the total amount of light passing through the turning film over the total amount of light incident upon the turning film. Thus, various turning film designs can be compared in terms of two critical quantities: maximum intensity ratio (or optical gain) and maximum intensity angle of the light that is transmitted through the turning film. | The present invention provides a light redirecting article for redirecting light toward a target angle, the light redirecting article comprising: an input surface comprising a plurality of light redirecting structures. Each light redirecting structure has (i) a near surface having two slopes, sloping away from normal in one direction as defined by a first inclination base angle β 1 , a second inclination angle β 2 , and a first half apex angle α 2 , for accepting incident illumination over a range of incident angles and (ii) a far surface sloping away from normal, in the opposite direction relative to the input surface, as defined by a second base angle γ 1 and a second half apex angle α 1 . In addition, light redirecting structures has (b) an output surface opposing to the input surface, wherein the near and far surfaces are opposed to each other at an angle (α 1 +α 2 ), and the base angle β 1 is greater than or equal to 90 degrees. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a rotor for a reluctance type electric rotating machine which can achieve the similar effects to those achieved by skew.
[0003] 2. Description of the Related Art
[0004] A reluctance type rotating machine or, for example, a reluctance type rotating machine provided with permanent magnets includes a rotor formed with a magnetic convex portion where a flux is easy to pass (d axis) and a magnetic concave portion where a flux is difficult to pass (q axis) and a permanent magnet which is disposed in a stator provided with a stator winding. The magnetic convex portion (d axis) has a high magnetic flux density in an air gap, whereas the magnetic concave portion (q axis) has a low magnetic flux density in an air gap. These variations in the magnetic flux density produce reluctance torque. Furthermore, torque is also developed by a magnetic attractive force and a magnetic repulsive force between poles of the permanent magnet and stator.
[0005] FIGS. 16 and 17 illustrate an example of conventional rotor for a reluctance type rotating machine with permanent magnets. The illustrated machine is an 8-pole machine. FIG. 16 is a side view of the rotor with an end plate and a rotational shaft being eliminated. FIG. 17 is a sectional view taken along line 17 - 17 . Referring to FIG. 16 , the rotor 100 includes a rotor core 101 made by stacking a number of annular silicon steel sheets. The rotor core 101 has pairs of generally rectangular magnet insertion holes 102 formed in an outer circumference thereof as shown in FIG. 17 . Permanent magnets 103 are inserted and fixed in the insertion holes 102 respectively. The outer circumference of the rotor core 101 is further formed with cavities 104 located between the respective pairs of permanent magnets 103 as shown in FIG. 17 . Each cavity 104 is formed into a generally triangular shape. In the rotor 100 , each pair of insertion holes 102 , permanent magnets 103 and each cavity 104 constitute the aforesaid magnetic concave portion 105 where a flux is difficult to pass (q axis). Each portion between the concave portions 105 constitutes the aforesaid magnetic convex portion 106 where a flux is easy to pass (d axis). The magnetic concave and convex portions 105 and 106 are formed alternately with a predetermined angle therebetween. See JP-A-2000-339922, for example.
[0006] The rotor core 101 has keys 107 formed on an inner circumference thereof. The keys 107 are adapted to engage key grooves of a rotational shaft respectively. Furthermore, a center line Lo passing the keys 107 is adapted to pass the center of the magnetic convex portion 106 . A center line La passes the center of the magnetic convex portion 105 adjacent to the center line Lo. The center line Lo is adapted to meet the center line La at an angle θ. The angle θ is at 22.5 degrees when the rotor 100 has 8 poles. The rotor 100 is adapted to be disposed in a stator (not shown) provided with a stator winding.
[0007] It is well known that squirrel-cage induction motors result in crawling due to torque developed by high harmonics. There is a possibility that permanent-magnet reluctance type rotating machines as the reluctance type rotating machine may cause the similar crawling to that caused by the squirrel-cage induction motors. As a result, the crawling results in torque ripple, oscillation, vibration and noise.
SUMMARY OF THE INVENTION
[0008] Therefore, an object of the present invention is to provide a rotor for a reluctance type rotating machine which can achieve the similar effects to those achieved by skew and reduce torque ripple, oscillation, vibration and noise.
[0009] The present invention provides a rotor for a reluctance type rotating machine comprising a rotor core formed by stacking a number of annular core materials each of which includes magnetic concave and convex portions alternately formed on an outer circumference thereof and a central through hole, the rotor core having a key axially extending on an outer circumference thereof, the rotor core being divided into a plurality of blocks, the core materials constituting at least one block having the magnetic concave and convex portions shifted by a predetermined angle relative the iron core materials constituting the other or another block on the basis of a center line passing the key, and a rotational shaft inserted through the central hole of the rotor core, the shaft having a key groove engaging the key of the rotor core.
[0010] In the above-described construction, the core materials constituting at least one block are formed so that the magnetic concave and convex portions are shifted by a predetermined angle from the core materials constituting the other or another block relative to a center line passing the key. Accordingly, for example, a center line passing the center of the magnetic concave portion of at least one block has a locus shifted from one of another or the other block. Consequently, since the similar effects to those achieved by skew can be achieved, the torque ripple, oscillation, vibration and noise can be reduced.
[0011] Each block may include the magnetic concave portions each of which is provided with a pair of magnet insertion holes which are opposed to each other so that a distance therebetween is gradually increased as the insertion holes proceed nearer to the outer circumference of the rotor, and permanent magnets may be inserted and fixed in the insertion holes respectively.
[0012] A magnetic torque by the permanent magnets can also be achieved in addition to reluctance torque. Furthermore, harmonic values of counter electromotive force can be reduced by the similar effects to those achieved by skew.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Other objects, features and advantages of the present invention will become clear upon reviewing the following description of the embodiments made with reference to the accompanying drawings, in which:
[0014] FIGS. 1A and 1B are sectional views taken along lines 1 A- 1 A and 1 B- 1 B in FIG. 2 , showing the rotor in accordance with a first embodiment of the present invention;
[0015] FIG. 2 is a side view of the rotor core of the rotor;
[0016] FIG. 3 is a partial plan view of the rotor;
[0017] FIG. 4 is a longitudinal section of the rotor;
[0018] FIG. 5 is a longitudinal section of the reluctance type rotating machine with permanent magnets;
[0019] FIG. 6 is a view similar to FIG. 2 , showing the rotor in accordance with a second embodiment of the invention;
[0020] FIG. 7 is a view similar to FIG. 3 ;
[0021] FIG. 8 is a sectional view taken along line 8 - 8 in FIG. 6 ;
[0022] FIG. 9 is a view similar to FIG. 2 , showing the rotor in accordance with a third embodiment of the invention;
[0023] FIG. 10 is a view similar to FIG. 3 ;
[0024] FIG. 11 is a sectional view taken along line 11 - 11 in FIG. 9 ;
[0025] FIG. 12 is a view similar to FIG. 2 , showing the rotor in accordance with a fourth embodiment of the invention;
[0026] FIG. 13 is a view similar to FIG. 3 ;
[0027] FIG. 14 is a view similar to FIG. 2 , showing the rotor in accordance with a fifth embodiment of the invention;
[0028] FIG. 15 is a sectional view taken along line 15 - 15 in FIG. 14 ;
[0029] FIG. 16 is a side view of a rotor of a conventional reluctance type rotating machine with permanent magnets; and
[0030] FIG. 17 is a sectional view taken along line 17 - 17 in FIG. 16 .
DETAILED DESCRIPTION OF THE INVENTION
[0031] Several embodiments of the present invention will be described. FIGS. 1A to 5 illustrate a first embodiment in which the invention is applied to a reluctance type rotating machine with permanent magnets. The reluctance type rotating machine possesses eight poles. A rotor 1 of the reluctance type rotating machine includes a rotor core 2 made by stacking a number of annular silicon steel sheets serving as a core material. The rotor core 2 is divided into four blocks 3 and 4 having the same thickness as shown in FIG. 2 . The blocks 3 and 4 are stacked alternately.
[0032] Each block 3 or the silicon steel sheets composing each block 3 will be described with reference to FIG. 1A . Each block 3 has a number of pairs of generally rectangular magnet insertion holes 5 formed in an outer circumferential portion thereof. The paired magnet insertion holes 5 are opposed to each other so that a distance therebetween is gradually increased as the magnet insertion holes 5 near an outer circumferential edge. Permanent magnets 6 are inserted into the paired magnet insertion holes 5 respectively and fixed by an adhesive agent, filler or the like. The outer circumferential portion of each block 3 also has cavities 7 formed between the permanent magnets 6 of each pair. Each cavity 7 is formed into a generally triangular shape having two sides parallel to the paired permanent magnets 6 and the other side extending along the outer circumference. The two sides of each cavity 7 may or may not be parallel to the paired permanent magnets 6 .
[0033] Each block 3 includes each portion thereof corresponding to the paired magnet insertion holes 5 , permanent magnets 6 and cavity 7 and serving as a magnetic concave portion 8 (q axis) where a flux is difficult to pass. Each block 3 further includes each portion thereof located between the magnetic concave portion 8 and serving as a magnetic convex portion 9 (d axis) where a flux is easy to pass. The magnetic concave and convex portions 8 and 9 are formed alternately so that each of the magnetic concave and convex portions 8 and 9 meets the other at a predetermined angle. Each block 3 further has two keys 10 and 11 which are formed on the inner circumference thereof so as to be 180-degree apart from each other and so as to extend axially.
[0034] A center line Lo passing the centers of the keys 10 and 11 also passes the magnetic convex portions 9 in each block 3 . Now, assume a center line Loa shifted from the center line Lo by a predetermined angle Δθ in the direction opposite the direction of rotation of the rotor (clockwise). The center line Loa forms a predetermined angle θ with a center line Lb passing the center of the magnetic concave portion 8 adjacent to the center line Loa. Accordingly, the center line Loa passes the center of the magnetic convex portion 9 . The angle θ is represented as 180/n when n is the number of poles of the rotor 1 . Furthermore, when a stator 50 (see FIG. 5 ) has slots the number of which is represented as 6×n, the magnetic concave and convex portions 8 and 9 representative of a pole position of each block 3 are shifted by the slot pitch a relative to the center line Lo. Accordingly, the angle Δθ is obtained from:
Δθ=(360× a )/(6× n )=(60× a )/ n
Thus, the angle Δθ is represented as −(60×a)/n in degree. The minus sign indicates shift in the direction opposite the direction of rotation of the rotor (clockwise).
[0036] Each block 4 or the silicon steel sheets composing each block 4 will be described with reference to FIG. 1B . Each block 4 has magnet insertion holes 12 which are similar to the magnet insertion holes 5 and formed in an outer circumferential portion thereof. Permanent magnets 13 are inserted into the paired magnet insertion holes 12 respectively and fixed by an adhesive agent, filler or the like. The outer circumferential portion of each block 4 also has cavities 14 which are similar to the cavities 7 and are formed between the permanent magnets 13 of each pair.
[0037] Each block 4 includes each portion thereof corresponding to the paired magnet insertion holes 12 , permanent magnets 13 and cavity 14 and serving as a magnetic concave portion 15 (q axis) where a flux is difficult to pass. Each block 4 further includes each portion thereof located between the magnetic concave portion 15 and serving as a magnetic convex portion 16 (d axis) where a flux is easy to pass. The magnetic concave and convex portions 8 and 9 are formed alternately so that each of the magnetic concave and convex portions 8 and 9 meets the other at a predetermined angle. Each block 4 further has two keys 10 and 11 which are formed on the inner circumference thereof so as to be 180-degree apart from each other and so as to extend axially.
[0038] A center line Lo passing the centers of the keys 10 and 11 also passes the magnetic convex portions 16 in each block 4 . Now, assume a center line Lob shifted from the center line Lo by a predetermined angle Δθ in the rotation direction X of the rotor (counterclockwise). The center line Lob forms a predetermined angle θ with a center line Lc passing the center of the magnetic concave portion 15 adjacent to the center line Lob. Accordingly, the center line Lob passes the center of the magnetic convex portion 16 . The angle θ is represented as 180/n when n is the number of poles of the rotor 1 . The angle Δθ is represented as +(60×a)/n in degree. The plus sign indicates deviation in the rotation direction X of the rotor (counterclockwise).
[0039] As obvious from FIGS. 1A and 1B , the block 4 is made by stacking the silicon steel sheets which are the same as those of the block 3 and reversed inside out. Accordingly, the blocks 3 and 4 of the rotor core 2 can be composed of a single type of silicon steel sheets. Two annular end plates 17 and 18 are attached to both ends of the rotor core 2 respectively as shown in FIG. 4 .
[0040] The rotating shaft 19 , rotor core 2 and end plates 17 and 18 are integrated together by shrinkage fitting thereby to be assembled. In this case, as shown in FIG. 4 , the keys 10 and 11 of the rotor core 2 are adapted to correspond with key grooves 20 of the rotating shaft 19 respectively. Only one of the key grooves 20 is shown in FIG. 4 . The rotating shaft 19 is formed with a flange 21 for positioning the rotor core 2 and end plates 17 and 18 .
[0041] Upon completion of assembly of the rotor 1 , the magnetic concave and convex portions 8 and 9 of the block 3 are shifted by the predetermined angle Δθ in the direction opposite the rotation direction X (clockwise) on the basis of the center line Lo. Further, the magnetic concave and convex portions 15 and 16 of the block 4 are also shifted by the predetermined angle Δθ in the rotation direction X (counterclockwise) on the basis of the center line Lo. As a result, the center lines Lb and Lc of the blocks 3 and 4 have linear loci which are zigzagged but not straightforward as in the conventional reluctance type rotating machines, as shown in FIG. 3 . Accordingly, the rotor 1 can achieve the effects similar to those of skew in the rotors for squirrel-cage induction motors. In this case, an amount of shift is required to be ±0 between the center lines Lb and the center lines Lc. More specifically, the sum total of a shift angle Δθ (−) of the center lines Lb and a shift angle Δθ (+) of the center lines Lc is required to be ±0 and the sum total of loci lengths of the center lines Lb (total thickness of the block 3 ) is required to be equal to the sum total of loci lengths of the center lines Lc (total thickness of the block 4 ) or the difference between both sums is required to be ±0.
[0042] The permanent-magnet reluctance type rotating machine 60 comprises the rotor 1 disposed in the stator provided with stator winding (not shown) as shown in FIG. 5 . The rotor 1 includes the magnetic concave portions 8 and 15 (q axis) where a flux is difficult to pass and the magnetic convex portions 9 and 16 (d axis) where a flux is easy to pass. By causing electric current to flow into the stator winding, magnetic energy is stored in air gaps over the magnetic concave and convex portions 8 and 15 , and 9 and 16 respectively. The magnetic energy differs from one air gap to another. The changes in the magnetic energy develop reluctance torque. Furthermore, since the rotor 1 is provided with the permanent magnets 6 and 13 , torque is also developed by a magnetic attractive force and magnetic repulsive force between the permanent magnets 6 and 13 and magnetic poles of the stator. Consequently, the rotor 1 is rotated.
[0043] In the foregoing embodiment, the magnetic concave and convex portions 8 and 9 of the block 3 are shifted by the predetermined angle Δθ in the direction opposite the rotation direction X (clockwise) on the basis of the center line Lo. Further, the magnetic concave and convex portions 15 and 16 of the block 4 are also shifted by the predetermined angle Δθ in the rotation direction X (counterclockwise) on the basis of the center line Lo. As a result, the linear loci of the center lines Lb and Lc of the blocks 3 and 4 are zigzagged and accordingly, the rotor 1 can achieve the effects similar to those of skew in the rotors for squirrel-cage induction motors. Consequently, torque ripple, oscillation, vibration and noise can be reduced in the permanent-magnet reluctance type rotating machine, and a peak value of back electromotive force can be reduced in the stator winding.
[0044] Additionally, an amount of shift is set so as to be ±0 between the center lines Lb and the center lines Lc in the rotor core 2 . Consequently, magnetic obstacle can be prevented although the rotor 1 can achieve the effects similar to those of skew in the rotors for squirrel-cage induction motors.
[0045] FIGS. 6 to 8 illustrate a second embodiment of the invention. Describing the difference of the second embodiment from the first embodiment, the rotor core 26 employed instead of the rotor core 2 includes blocks 3 and 27 stacked alternately. Each block 27 comprises the silicon steel sheets which are the same as those of each block 4 but are reversed by 180 degrees or more specifically, each block 4 is reversed by 180 degrees. The other construction of the rotor of the second embodiment is the same as that of the first embodiment.
[0046] In the construction of the second embodiment, too, the linear loci of the center lines Lb and Lc of the blocks 3 and 27 are zigzagged in the same manner as in the first embodiment. Consequently, the rotor of the second embodiment can achieve the same effects as those of the first embodiment.
[0047] The annular silicon steel sheets constituting the rotor core 26 are formed by punching a rolled elongated silicon steel sheet. It is well known that the rolling results in shift in the thickness in the rolling direction and in the direction perpendicular to the rolling direction. In the second embodiment, however, the blocks 27 obtained by reversing the blocks 4 by 180 degrees. Consequently, since the deviation in the thickness is absorbed, the thickness of the rotor core 26 can be rendered uniform.
[0048] The thicknesses of the four blocks 3 and 27 are equal to one another in the second embodiment. However, the total thickness of the blocks having the respective center lines Lb may be equal to the total thickness of the blocks having the respective center lines Lc.
[0049] FIGS. 9 to 11 illustrate a third embodiment of the invention. Describing the difference of the third embodiment from the first embodiment, the rotor core 28 employed instead of the rotor core 2 is divided into four blocks 29 , 30 and 31 . Each block 29 has a thickness set to be equal to or less than one half of that of each of blocks 30 and 31 . The thickness of each block 29 is set at one half of that of each of the blocks 30 and 31 in the embodiment. The block 30 is formed by stacking the same silicon steel sheets as those of each block 4 (see FIG. 1B ). The block 31 is formed by stacking the same silicon steel sheets as those of each block 3 (see FIG. 1A ). The block 30 has a thickness equal to one of the block 31 and larger than the blocks 3 and 4 . The rotor core 28 has a thickness equal to that of the rotor core 2 .
[0050] Each block 29 or the silicon steel sheets composing each block 29 will be described with reference to FIG. 11 . Each block 29 has a number of pairs of generally rectangular magnet insertion holes 32 which are formed in an outer circumferential portion thereof and are similar to the insertion holes 5 . The permanent magnets 33 are inserted into the paired magnet insertion holes 32 respectively and fixed by an adhesive agent, filler or the like. The outer circumferential portion of each block 29 also has cavities 34 which are formed between the permanent magnets 33 of each pair and are similar to the cavities 7 .
[0051] Each block 29 includes each portion thereof corresponding to the paired magnet insertion holes 32 , permanent magnets 33 and cavity 34 and serving as the magnetic concave portion 35 (q axis) where a flux is difficult to pass. Each block 29 further includes each portion thereof located between the magnetic concave portion 35 and serving as a magnetic convex portion 36 (d axis) where a flux is easy to pass. The magnetic concave and convex portions 35 and 36 are formed alternately with a predetermined angle therebetween. Each block 29 further has two keys 10 and 11 which are formed on the inner circumference thereof so as to be 180-degree apart from each other and so as to extend axially.
[0052] The center line Lo passing the centers of the keys 10 and 11 also passes the magnetic convex portions 36 in each block 29 . The center line Lo forms a predetermined angle θ with a center line Ld passing the center of the magnetic concave portion 35 adjacent to the center line Lo. The angle θ is represented as 180/n when n is the number of poles of the rotor 1 . Thus, the silicon steel sheets constituting each block 29 are similar to those employed in the conventional rotor core as shown in FIG. 17 .
[0053] In the above-described construction, the center lines Lb and Lc of the blocks 31 and 30 have linear loci which are zigzagged. Accordingly, the rotor can achieve the effects similar to those of skew in the rotors for squirrel-cage induction motors as in the first embodiment. In particular, the center lines Ld of the blocks 29 located at both ends of the rotor core 28 have loci are located between the loci of the center lines Lc and Lb. Accordingly, since the mechanical balance can be improved between the rotor core 28 and the stator winding, the waveform characteristic of the back electromotive force can be improved in the stator winding.
[0054] FIGS. 12 and 13 illustrate a fourth embodiment of the invention. The difference of the fourth embodiment from the first embodiment will be described. The rotor core 39 employed instead of the rotor core 2 includes a block 40 formed by integrating the blocks 3 and a block 41 formed by integrating the blocks 4 .
[0055] In the foregoing construction, the loci of the center lines Lb and Lc of the respective blocks 40 and 41 are as shown in FIG. 13 . Accordingly, the fourth embodiment can achieve the same effects as those of the first embodiment.
[0056] FIGS. 14 and 15 illustrate a fifth embodiment of the invention. The difference of the fifth embodiment from the fourth embodiment will be described. The rotor core 42 employed in the fifth embodiment includes blocks 43 and 44 . One half 44 a of the block 44 is formed by stacking the silicon steel sheets (see FIG. 1B ) which are the same as those of the block 41 . The other half 44 b of the block 44 is formed by stacking the silicon steel sheets (see FIG. 8 ) which are the same as those of the block 27 . Furthermore, one half 43 a of the block 43 is formed by stacking the silicon steel sheets ( FIG. 1A ) which are the same as those of the block 40 . The other half 43 b is formed by reversing by 180 degrees and stacking the silicon steel sheets which are the same as those of the block 40 or more specifically, by reversing the portion 43 a by 180 degrees. The other construction of the rotor of the fifth embodiment is the same as that of the first embodiment. Consequently, the fifth embodiment can achieve the same effects as those of the fourth and second embodiments.
[0057] The portions 43 a and 43 b and the portions 44 a and 44 b constituting the respective blocks 43 and 44 are set at one halves of the thicknesses of the blocks 43 and 44 respectively in the fifth embodiment. However, these portions may be set substantially at one halves respectively.
[0058] The permanent magnets are provided on the rotor core in each of the foregoing embodiments. However, the permanent magnets may or may not be provided on the rotor core. Further, the generally triangular cavities are formed in the rotor core so as to compose the concave and convex portions in each of the foregoing embodiments. However, the cavities may be circular, elliptic, rectangular or rhombic. Additionally, the rotor core may have mechanical concave and convex portions formed therein so that the magnetic concave and convex portions are formed.
[0059] The number of poles of the rotor should not be limited to eight. The same effect can be achieved even when the number of poles is any other number. Furthermore, the number of slots of the stator may be set at any suitable number. Additionally, the number of blocks of the rotor should not be limited to two and four. Five or more blocks may be provided by stacking the silicon steel sheets having the magnetic concave and convex portions shifted. In this case, an amount of shift of the center line is required to be ±0.
[0060] The foregoing description and drawings are merely illustrative of the principles of the present invention and are not to be construed in a limiting sense. Various changes and modifications will become apparent to those of ordinary skill in the art. All such changes and modifications are seen to fall within the scope of the invention as defined by the appended claims. | A rotor for a reluctance type rotating machine includes a rotor core formed by stacking a number of annular core materials each of which includes magnetic concave and convex portions alternately formed on an outer circumference thereof and a central through hole, the rotor core having a key axially extending on an outer circumference thereof, the rotor core being divided into a plurality of blocks, the core materials constituting at least one block having the magnetic concave and convex portions shifted by a predetermined angle relative to the core materials constituting the other or another block on the basis of a center line passing the key, and a rotational shaft inserted through the central hole of the rotor core, the shaft having a key groove engaging the key of the rotor core. | 8 |
RELATED APPLICATIONS
The present application claims priority to Japanese Application Number 2013-001300, filed Jan. 8, 2013, the disclosure of which is hereby incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to a power supply device for electric discharge machining, and in particular to a power supply device for finish machining.
2. Description of the Related Art
In electric discharge machining, arc discharges are generated by applying voltages between an electrode and a workpiece in a machining fluid. The heat generated by these electric discharges melts the workpiece while rapidly heating the machining fluid, causing its vaporization and explosion that blows off the molten portion of the workpiece. Machining progresses by repeating this process at a high frequency. Since the machined surface is formed by a collection of small craters produced by electric discharges, the size of each crater determines the surface roughness.
In wire electric discharge machining, which is a kind of electric discharge machining, it is generally known that electric discharge of short duration is repeated at a high frequency by applying a high-frequency AC voltage 102 , which is a power supply output voltage 100 , across a machining gap between a wire electrode and a workpiece to achieve micromachining, as shown in FIGS. 10A and 10B . FIG. 10A shows an exemplary high-frequency AC voltage 100 that is generated by the power supply in a wire electric discharge machine. Rectangular wave voltages generated by the power supply are transmitted through a coaxial cable or the like from the power supply to the machining gap and applied in the sinusoidal form of blunt waveforms as shown in FIG. 10B across the machining gap.
Japanese Patent Application Laid-Open No. 61-260915, for example, discloses that a machined surface with a surface roughness of 1 μm Rmax or lower can be obtained by applying high-frequency AC voltages in the range of 1-5 MHz. Japanese Patent Application Laid-Open No. 2010-194693 discloses a machining technique, in which positive and negative voltages are applied, as shown in FIG. 12A , across the machining gap between a wire electrode and a workpiece with a quiescent period equal to or longer than individual voltage application periods provided between individual voltage applications so as to obtain trapezoidal wave voltages.
The technique disclosed in Japanese Patent Application Laid-Open No. 61-260915, however, apparently has the following problems:
(1) Degradation in Straightness Accuracy
If high-frequency AC voltages are used in wire electric discharge machining, the wire electrode bends due to electrostatic attraction between the wire electrode and the workpiece, because voltages are continuously applied across the machining gap, as shown in FIG. 10B . This degrades the straightness accuracy of machining, because the amount of machining increases in the central part of the sheet thickness of the workpiece, resulting in a barrel-like form.
(2) Degradation in Roughness of the Machined Surface
When machining is performed using an AC voltage, electric discharges are theoretically interrupted at every half cycle of the voltage, i.e., at zero crossing points 104 of the discharge current, as shown in FIG. 10B , because the voltages are reversed from positive to negative or from negative to positive over time. At higher AC frequencies, individual electric discharge arcs are not sufficiently extinguished. If electric discharges occur immediately after voltage applications, the electric discharges tend to occur repeatedly at the same place. If electric discharges continue at a high frequency, the resultant surface roughness would become worse than that obtained by AC half-wave electric discharges. Since the surface roughness tends to vary with the density of electric discharges, streaks may be produced on the machined surface.
(3) Difficulty in Determining the Machining State
In electric discharge machining, the machining state is typically determined by measuring an average voltage applied across the machining gap in order to control the electrode feeding speed and to change the machining conditions. With high-frequency AC voltages at several MHz or higher, however, measurement errors increase because a rectifier circuit for obtaining the average voltage does not respond. At high frequencies, resonance phenomena often occur between the machining power supply and the machining gap. If the electric discharge gap length, sheet thickness, the machining fluid flowing state, or the like changes, electric constants of the machining gap change, which inevitably causes the machining voltage to vary. This makes it more difficult to determine the machining state from the average voltage. This is a bottleneck in improving the machining accuracy, because it is difficult to perform feedback control responsive to the machining state, so that the electrode is fed at a constant speed in the finishing region, for example.
As a solution to these problems, the above-mentioned Japanese Patent Application Laid-Open No. 2010-194693 discloses a machining technique using a trapezoidal wave voltage 118 as shown in FIG. 12C . The trapezoidal wave voltage 118 is formed by applying a power supply output voltage 110 across the machining gap between an electrode and a workpiece with a quiescent period 112 equal to or longer than individual voltage application periods provided between applications of positive voltage 114 and negative voltage 116 , as shown in FIG. 12A . FIG. 12B shows a power supply output current which corresponds to the power supply output voltage shown in FIG. 12A , wherein positive currents 111 and negative currents 113 are alternately applied.
In electric discharge machining, multiple machining is typically performed by gradually weakening the intensity of machining pulses in the order of rough machining, intermediate machining, and finish machining until the desired accuracy and surface roughness are achieved. In recent years, in order to reduce the machining period, attempts have been made to reduce the number of machining times by performing part of the intermediate machining using a power supply for finish machining. More specifically, in the prior art, rough machining and intermediate machining are performed until a surface roughness of 3-5 μm Rz is achieved and then machining is performed using a power supply for finish machining several times up to a surface roughness of about 1 μm Rz. In recent years, instead, when a surface roughness of about 10 μm Rz is achieved, machining is performed using a power supply for finish machining to reduce the number of machining times and the machining period.
In this case, the amount of machining per unit time of the power supply for finish machining increases than ever and accordingly the output voltage from the machining power supply increases, which overheats switching elements and other components in the conventional power supply exceeding their rated values and makes them unserviceable. There is the need, therefore, to provide a new power supply that can output a higher current.
FIG. 11 is a schematic block diagram of the bipolar voltage application circuit 10 that is typically used as in Japanese Patent Application Laid-Open Nos. 61-260915 and 2010-194693 mentioned above.
Reference numerals 11 and 12 represent DC power supplies; reference numerals 13 and 14 represent switching elements. Reference numerals 15 , 16 , and 17 represent a damping resistance, inductance, and a resistance, respectively. Reference numerals 18 and 19 represent a line-to-line capacitance and an electrode, respectively. Reference numerals 20 , 21 , and 22 represent a workpiece, machining gap stray capacitance, and a leak resistance, respectively. The inductance 16 , resistance 17 and line-to-line capacitance 18 represent equivalent components included in the wiring route represented by the feeding cable 24 between the power supply and the machining gap. Reference character Vbb represents a voltage applied across the machining gap between the electrode 19 and the workpiece 20 . The switching elements 13 , 14 are turned on and off by a control circuit (not shown) and output power supply output voltages shown in FIGS. 10A and 12A , for example.
The inductance 16 , resistance 17 , line-to-line capacitance 18 of the feeding cable 24 exist in the bipolar voltage application circuit 10 and the machining gap stray capacitance 21 and leak resistance 22 exist in the machining gap between the opposite surfaces of the electrode 19 and the workpiece 20 . In rough machining and intermediate machining, a machining current having sharply rising peaks is favorable, so the circuit is configured such that the impedance in the entire circuit becomes as small as possible, which reduces the inductance L and resistance R and increases the line-to-line capacitance C. If the output energy from the power supply is reduced to improve the surface roughness as in the finish machining, the stray capacitance cannot be charged rapidly and the frequency of the high-frequency AC voltages applicable across the machining gap including the line-to-line capacitance is limited to about 200-300 kHz.
SUMMARY OF THE INVENTION
In view of these problems, the power supply device is configured such that 500 kHz or higher frequency AC voltages can be applied for finish machining by designing the circuit so as to switch to a feeding cable having a reduced line-to-line capacitance and reduce the machining gap stray capacitance as far as possible.
In such a circuit for finish machining, if positive and negative voltages are applied across the machining gap with a quiescent period provided between individual voltage applications as disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 2010-194693, charges are first accumulated in the line-to-line capacitance 18 and machining gap stray capacitance 21 , which causes the machining gap voltage Vbb to rise. In a subsequent quiescent period in which voltages are not applied, the charges accumulated in the line-to-line capacitance 18 and the machining gap stray capacitance 21 are discharged through the leak resistance 22 and thus the machining gap voltage gradually drops. When the voltage application frequency increases to 500 kHz or more as in the above-mentioned Japanese Patent Application Laid-Open No. 2010-194693, the quiescent period becomes relatively short and the voltage drop during the quiescent period is accordingly reduced and substantially negligible.
If a damping resistance 15 for vibration suppression is inserted into the circuit to suppress vibrations in the transition states between the voltage application periods and the quiescent periods, the machining gap voltage can be shaped into a substantially trapezoidal form as shown in FIG. 12C . A higher resistance value of the damping resistance 15 provides a greater vibration suppression effect but reduces the voltage changing speed, resulting in a blunt waveform.
Here, in a power supply in the prior art, the positive and negative polarities of the voltages to be applied across the machining gap are alternated with a quiescent period in between as shown in FIG. 12A . In this scheme, when electric discharge does not occur, the machining power supply needs to charge the machining gap stray capacitance voltage from −E to +E or from +E to −E, which requires fourfold energy compared with when charging from 0 V to +E or from 0 V to −E.
An object of the present invention is to provide a power supply device for electric discharge machining that minimizes the output current from the power supply for finish machining by applying trapezoidal wave voltages, such that a power supply in the prior art can also be used even in a part of the intermediate machining region.
The power supply device for electric discharge machining according to the present invention includes a voltage applying means for applying both positive and negative voltages across the machining gap between the electrode and the workpiece at intervals of not longer than one microsecond with a quiescent period equal to or longer than each voltage application period provided between individual voltage applications, a machining-gap open-state determining means for determining whether or not the machining gap between the electrode and the workpiece is in open state before individual voltage applications, an average voltage detecting means for detecting an average machining gap voltage during machining, the average machining gap voltage being an average value of the machining gap voltages over a period from a preset reference time to the present time, an open-state counting means for counting the number of successive machining gap open states having the same polarity, and an applied polarity determining means for determining the polarity of the voltage to be applied across the machining gap on the basis of the result of determination by the machining-gap open-state determining means, the average machining gap voltage detected by the average voltage detecting means, and the number of successive machining gap open states counted by the open-state counting means. The voltage of the polarity determined by the applied polarity determining means is applied across the machining gap.
According to the present invention, if electric discharge does not occur, the positive and negative polarities are not alternately switched and the voltage of the same polarity is applied next, unlike in the prior art in which the positive and negative polarities of the voltages to be applied across the machining gap are simply alternated with a quiescent period in between. Since the polarity of the voltage to be applied next is determined on the basis of the result of determination by the machining-gap open-state determining means, the average machining gap voltage, and the number of successive open states with the same polarity, it is possible to reduce wasteful energy that does not contribute directly to machining because, when electric discharge does not occur, the voltage to be applied next need not be charged by switching from −E to +E or from +E to −E.
When the machining gap before voltage application is in open state, the applied polarity determining means compares a preset maximum number of successive open states with the value counted by the open-state counting means. If the value counted by the open-state counting means does not reach the maximum number of successive open states, the applied polarity determining means can determine the application of the same polarity as the last one across the machining gap; if the value counted by the open-state counting means reaches the maximum number of successive open states, the applied polarity determining means can determine the application of the polarity opposite to the last one. Furthermore, if the machining gap is not in open state before voltage application, when the average voltage detecting means detects a positive polarity, the applied polarity determining means can determine the application of the negative polarity as the polarity to be applied next, and when the average voltage detecting means detects a negative polarity, the applied polarity determining means can determine the application of the positive polarity as the polarity to be applied next.
In the embodiment described above, it is only necessary to supplement the amount of machining gap voltage reduced by the leak resistance before voltage application as shown in FIG. 3 , because the voltage of the same polarity as the last one is applied until the preset maximum number of successive open states is reached. This significantly reduces the output current from the power supply.
If water or other electrolytic material is used as the machining fluid, successive open states for a long time with the same polarity may cause electrolytic corrosion due to unipolar machining. This electrolytic corrosion or other problems due to unipolar machining can be prevented by forcibly switching the polarity of the applied voltage when the number of applications of voltage of the same polarity reaches a preset number of successive open states.
Furthermore, when electric discharge occurs or the machining gap is short-circuited, i.e., not in open state, the voltage of the polarity opposite to the result of detection by the average voltage detecting means is applied next, so that the average machining gap voltage during machining approaches 0 V and thereby electrolytic corrosion or other problems are prevented.
When the absolute value of the voltage applied across the machining gap between the electrode and the workpiece exceeds the preset maximum voltage, the application of voltages may be inhibited.
When voltages of the same polarity are successively applied across the machining gap, the machining gap voltage may rise stepwise to converge to a final value, not becoming constant. In the above embodiment, however, a maximum absolute value of the voltages applied across the machining gap between the electrode and the workpiece is set in advance and, when this maximum value is exceeded, the application of voltages is inhibited by forcibly turning off the switching elements in the voltage applying means. This can prevent the machining gap voltage to rise stepwise and can thus avoid the situation in which individual waveforms of the voltages applied across the machining gap do not become constant.
If an average value of the output current from the voltage applying means over a period from a preset reference time to the present time during machining exceeds a preset maximum current, the voltage application may be suspended and resumed after a predetermined quiescent period.
In the above embodiment, when the machining current exceeds the preset maximum current, the application of voltages is temporarily stopped, so that machining can be performed always at the rated current and the machining capacity can actually be enhanced.
As described above, the present invention can provide a power supply device for electric discharge machining in which the polarity of the voltage to be applied is determined on the basis of the result of determination by the machining-gap open-state determining means, the average machining gap voltage during machining, and the number of successive open states with the same polarity, so that the polarity switching frequency of the voltages to be applied across the machining gap can be reduced such that electrolytic corrosion does not occur, the output current that does not contribute directly to machining can be reduced, a power supply having a large output current is not required, and the amount of machining can be increased even with a small current.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and features of the present invention will be apparent from the following description of embodiments with reference to the appended drawings, in which:
FIG. 1 shows a first embodiment of the power supply device for electric discharge machining according to the present invention;
FIG. 2A illustrates the change in voltage waveform of a high-frequency AC voltage between the machining gap open periods and the electric discharge periods in the prior art;
FIG. 2B illustrates the change in voltage waveform of a trapezoidal wave voltage between the machining gap open periods and the electric discharge periods in the prior art;
FIG. 3 shows the changes in the power supply output voltage, power supply output current, and machining gap voltage in the power supply device for electric discharge machining according to the present invention;
FIG. 4 is a timing chart showing an operation of the power supply device for electric discharge machining in FIG. 1 ;
FIG. 5 is a flowchart illustrating an operation of the power supply device for electric discharge machining in FIG. 1 ;
FIG. 6 shows a second embodiment of the power supply device for electric discharge machining according to the present invention;
FIG. 7A shows the change in voltage waveform of the machining gap voltage in the power supply device for electric discharge machining in FIG. 6 , illustrating that successive applications of voltages of the same polarity raises stepwise the machining gap voltage;
FIG. 7B shows the change in voltage waveform of the machining gap voltage in the power supply device for electric discharge machining in FIG. 6 , illustrating that the waveforms of the voltages applied in individual cycles can be kept uniform by forcibly turning off the switching command when the maximum machining gap voltage is exceeded;
FIG. 8 shows a third embodiment of the power supply device for electric discharge machining according to the present invention;
FIG. 9 is a timing chart illustrating an operation of the power supply device for electric discharge machining in FIG. 8 ;
FIG. 10A shows the change in power supply output voltage in the power supply device for electric discharge machining in the prior art;
FIG. 10B shows the change in machining gap voltage in the power supply device for electric discharge machining in the prior art;
FIG. 11 is a schematic block diagram of a bipolar voltage application circuit; and
FIG. 12A to 12C show the changes in power supply output voltage ( FIG. 12A ), power supply output current ( FIG. 12B ), and machining gap voltage ( FIG. 12C ) in the power supply device for electric discharge machining in the prior art in which positive and negative polarities of the voltages to be applied are alternated with a quiescent period provided between individual voltage applications.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIG. 1 , a first embodiment of the power supply device for electric discharge machining according to the present invention will be described.
In FIG. 1 , reference characters 41 X, 41 Y denote DC power supplies. Reference characters 42 X, 42 Y denote switching elements that output positive and negative polarity voltages, respectively. Reference numerals 43 , 44 , 45 , and 46 denote a damping resistance, feeding cable, electrode, and a workpiece, respectively. Reference numerals 47 , 48 denote voltage dividing resistors. Reference numerals 51 , 53 , and 55 denote a machining gap voltage integrator circuit, machining gap voltage absolute value circuit, and a voltage application timing generator, respectively. Reference numeral 57 denotes an open-state determining voltage V1. Reference numerals 59 , 61 , 63 , and 65 denote a comparator, preset counter, OR gate, and a flip-flop, respectively. Reference characters 67 X, 67 Y denote AND gates. Reference characters 69 X and 69 Y denote first and second driver circuits.
The machining gap voltage between the electrode 45 and the workpiece 46 is divided by a voltage divider including voltage dividing resistors 47 , 48 and the divided voltage is input to the machining gap voltage integrator circuit 51 and the machining gap voltage absolute value circuit 53 .
When the divided voltage is input, the machining gap voltage integrator circuit 51 determines an average machining gap voltage during machining, which is a value averaged over a period from a preset reference time. If the average machining gap voltage is positive, the machining gap voltage integrator circuit 51 outputs a high-level logic signal. When the average machining gap voltage is negative, the machining gap voltage integrator circuit 51 outputs a low-level logic signal. On the other hand, in the machining gap voltage absolute value circuit 53 , when the divided voltage is input, the absolute value of the machining gap voltage is output in the form of an analog voltage. The output analog voltage is input to the comparator 59 .
The comparator 59 compares the voltage output from the machining gap voltage absolute value circuit 53 (absolute value of the machining gap voltage) with a preset open-state determining voltage 57 (V1). If the absolute value of the machining gap voltage is equal to or lower than the open-state determining voltage V1, the output from the comparator 59 becomes high.
The voltage application timing generator 55 outputs an ON command a toward the AND gates 67 X, 67 Y to drive the switching elements in association with preset application periods and quiescent periods. The voltage application timing generator 55 also outputs count pulses b toward the preset counter 61 to count the number of voltage applications.
The preset counter 61 counts the count pulses b sent from the voltage application timing generator 55 . When the counted value reaches a preset value, the preset counter 61 outputs a count-up signal c and resets an internal counter value (clears the value to 0). The preset counter 61 has a reset input. When a high-level signal is input through the reset input, the internal counter value is reset (cleared to 0).
The output from the comparator 59 and the count-up signal output from the preset counter 61 are input to the OR gate 63 and a signal resulting from the logical OR of these inputs is output. This logical OR signal from the OR gate 63 is input to the clock input of the flip-flop 65 .
The output from the machining gap voltage integrator circuit 51 is input to the flip-flop 65 as D input and the output from the OR gate 63 is input as clock input. At a rising edge of the clock input signal from the OR gate 63 , Q and *Q outputs are determined on the basis of the state of the D input. When a clock input signal is input to the flip-flop 65 while its D input is high, the Q output becomes high and the *Q output becomes low. When a clock input signal is input while the D input is low, the Q output becomes low and the *Q output becomes high.
Referring now to FIGS. 2A and 2B , the changes in voltage waveform of a high-frequency AC voltage and a trapezoidal wave voltage between the machining gap open periods and the electric discharge periods in the prior art will be described.
FIG. 2A shows a high-frequency AC voltage 150 . FIG. 2B shows a trapezoidal wave voltage 158 . In FIG. 2A , reference numerals 152 , 154 , 156 indicate the points at which electric discharge occurs. Typically, electric discharge often occurs near peak values of the machining gap voltage. Then, the machining gap voltage rapidly drops to an arc voltage as shown in FIG. 2A . Even if electric discharge does not occur, the machining gap voltage drops after reaching its peak. Especially when electric discharge is delayed and occurs after the peak, the difference in voltage is small between the case in which electric discharge has occurred and the case in which electric discharge does not occur.
On the other hand, the voltage waveform of the trapezoidal wave voltage 158 changes between the machining gap open periods and the electric discharge periods as shown in FIG. 2B . If electric discharge does not occur during one cycle period, the voltage is substantially maintained at the peak value as indicated by a dotted line. If electric discharge occurs at the points of occurrence of electric discharge indicated by reference numerals 160 , 162 , 164 , the machining gap voltage drops to the arc voltage and then is kept equal to or lower than the arc voltage during the quiescent periods indicated by reference numerals 166 , 168 , 170 because the output from the power supply is left turned off.
As can be seen from the large difference between the voltage values indicated by the dotted and solid lines in the voltage waveforms in FIGS. 2A and 2B , the machining gap voltage clearly changes between the presence and absence of electric discharge. Accordingly, the presence or absence of electric discharge can be detected easily by comparing the machining voltages with a predetermined reference voltage. By making use of this, the comparator 59 in the power supply device illustrated in FIG. 1 detects the presence or absence of electric discharge by comparing the absolute value of the machining gap voltage output from the machining gap voltage circuit 53 with the open-state determining voltage V1.
Referring next to the timing chart in FIG. 4 , an operation of the power supply device shown in FIG. 1 will be described below.
The “machining gap voltage 71 ” is the voltage applied across the machining gap between the electrode 45 and the workpiece 46 . The “average machining gap voltage 73 ” is the average value of the machining gap voltage during machining (i.e., an average value of the machining gap voltages measured by the machining gap voltage integrator circuit 51 over a period from a preset reference time). The “counter 75 ” is a counted value in the preset counter 61 . In this embodiment, five values (0, 1, 2, 3, and) are set as the preset values, the counted value 4 is then reset to 0.
Reference characters a, b, c, d, e, f, g, h, X, Y in FIG. 4 represent high or low levels of the signals in the wires denoted by the same reference characters in FIG. 1 . More specifically, reference character a represents an ON command signal that is output by the voltage application timing generator 55 at predetermined intervals to drive the switching elements. Reference character b represents the count pulse signal that is output by the voltage application timing generator 55 before the end of each quiescent period. Reference character c represents the count-up signal output by the preset counter 61 . Reference character d represents the signal output by the comparator 59 . This signal becomes high when the absolute value of the machining gap voltage becomes equal to or lower than the open-state determining voltage V1. Reference character e represents a signal that results from the logical OR of the output from the comparator 59 and the count-up signal from the preset counter 61 and is input to the flip-flop 65 as a clock signal. Reference character f represents the output from the machining gap voltage integrator circuit 51 . This signal becomes high when the average machining gap voltage during machining (i.e., an average value of the machining gap voltages over a period from a preset reference time) is positive and becomes low when the average machining gap voltage is negative. Reference character g represents the Q output of the flip-flop 65 , while reference character h represents the *Q output of the flip-flop 65 .
Initially, the average machining gap voltage 73 is a negative voltage having a small absolute value, so that the signal f becomes low, the Q output g of the flip-flop becomes low, and the *Q output h becomes high. When an operation starts in this state, the voltage application timing generator 55 first outputs an ON command a to turn on the switching elements. Since the output of the comparator 59 is kept high, the output states of the flip-flop 65 remain in the initial state, i.e., the Q output g is low and the *Q output h is high. This causes one (first) driver circuit 69 X of the two driver circuits 69 X, 69 Y to operate and output a drive signal X to the switching element on the positive voltage application side. With this, a positive voltage pulse is applied across the machining gap. If the machining gap open state continues as is, the machining gap voltage gradually drops after the switching element is turned off, so its waveform becomes generally trapezoidal.
Before the end of the quiescent period, the voltage application timing generator 55 outputs a count pulse b to increment the counter value (counter 75 ) of the preset counter 61 from 0 to 1. Subsequently, the voltage application timing generator 55 outputs again an ON command a to turn on the switching element. Then, if the machining gap is still open, the signals do not change and the application of the positive voltage is repeated and the value of the average machining gap voltage 73 increases until the counted value in the preset counter 61 reaches 4.
Before the end of a quiescent period after the positive polarity voltage is successively applied five times, the voltage application timing generator 55 outputs the count pulse b to increment the counter value to 5, which matches the preset value 5. With this, the preset counter 61 outputs the count-up signal c and clears the value in the internal counter to 0. With the output of the count-up signal c, the clock input e to the flip-flop 65 changes from low to high. Since the signal f to the input D of the flip-flop 65 is high, the Q and *Q outputs are reversed, so that the signal g changes from low to high and the signal h changes from high to low.
In this state, if the voltage application timing generator 55 outputs an ON command a to turn on the next switching element, the other (second) driver circuit 69 Y of the two driver circuits 69 X, 69 Y operates and outputs a drive signal Y to the switching element on the negative voltage application side. This causes the average machining gap voltage 73 that has been rising to start to drop. As in the above case in which the positive voltage pulse is applied across the machining gap, if the machining gap stays open with the negative polarity voltage pulse applied across the machining gap, the counted value (counter 75 ) in the preset counter 61 increments at every voltage application pause cycle.
Suppose here that an insulation breakdown occurs in the machining gap and electric discharge occurs when the counted value (counter 75 ) in the preset counter 61 reaches 2 as shown in FIG. 4 , for example. This causes the machining gap voltage to rapidly drop from the open-circuit voltage to about an arc voltage, which is equal to or lower than the open-state determining voltage. This changes the output d of the comparator 59 from low to high. The output d (high) from the comparator 59 is input to the reset input of the preset counter 61 to clear the counter value of the preset counter 61 to 0 and at the same time is input to the OR gate 63 to change the clock input e output from the OR gate 63 toward the flip-flop 65 from low to high.
Since the average machining gap voltage is still biased toward the positive polarity as shown in the average machining gap voltage graph in FIG. 4 , the signal f to the input D stays high and the output signals Q, *Q from the flip-flop 65 do not change. Accordingly, the next application of voltage is again to the negative polarity side.
Since the output d of the comparator 59 stays high, the counter value of the preset counter 61 is 0 even if the next count pulse b is input to the preset counter 61 .
If the machining gap is short-circuited, which is a state in which the machining gap voltage does not rise even if the switching element of the power supply is turned on, the output of the comparator 59 stays high and accordingly the counter value of the preset counter 61 is left cleared to 0.
When the machining gap returns from the short-circuited state to the open state in the next voltage application cycle, the counted value in the preset counter 61 is incremented one by one at the end of each voltage application cycle. When the counted value reaches 5, the preset counter 61 outputs the count-up signal c, which clears the internal counter value to 0. At this time, since the average machining gap voltage is negative as shown in the graph of the average machining gap voltage 73 in FIG. 4 , the signal f to the input D of the flip-flop 65 is low and the outputs Q, *Q of the flip-flop 65 are reversed again, so that the Q output signal g changes from high to low and the *Q output signal h changes from low to high. Consequently, the output X of the driver circuit 69 X on the positive polarity side becomes effective and the positive voltage is applied across the machining gap.
FIG. 5 is a flowchart illustrating an operation of the power supply device for electric discharge machining in FIG. 1 . The operation will now be described step by step.
(Step SA 1 ) The maximum number C (five in this embodiment) of successive open states of the machining gap is set as a preset value in the preset counter 61 . (Step SA 2 ) The counted value c in the preset counter 61 is cleared (reset to 0). (Step SA 3 ) A positive polarity pulse is applied. (Step SA 4 ) Whether the machining gap is in open state or not is determined. If the machining gap is in open state (Yes), the process proceeds to Step SA 6 ; if electric discharge occurs or the machining gap is short-circuited, i.e., not in open state (No), the process proceeds to Step SA 5 . (Step SA 5 ) Whether the average value of the machining gap voltage over a period from the preset reference time to the present time (i.e., average machining gap voltage) is equal to or higher than 0 is determined. If the average machining gap voltage is equal to or higher than 0 (Yes), the process proceeds to Step SA 8 ; if lower than 0 (No), the process returns to Step SA 2 . (Step SA 6 ) The counted value c in the preset counter 61 is incremented by one. (Step SA 7 ) Whether or not the current counted value c is lower than the maximum number C of successive open states set in Step SA 1 is determined. If the counted value c is lower than the maximum number C of successive open states (Yes), the process returns to Step SA 3 ; if equal to or higher than the maximum number C of successive open states (No), the process proceeds to Step SA 8 . (Step SA 8 ) The counted value c is cleared (reset to 0). (Step SA 9 ) A negative polarity pulse is applied. (Step SA 10 ) Whether the machining gap is in open state or not is determined.
If the machining gap is in open state (Yes), the process proceeds to Step SA 12 ; if electric discharge occurs or the machining gap is short-circuited, i.e., not in open state (No), the process proceeds to Step SA 11 .
(Step SA 11 ) Whether the average value of the machining gap voltages over a period from the preset reference time to the present time (i.e., machining gap average voltage) is equal to or higher than 0 is determined. If the machining gap average voltage is equal to or higher than 0 (Yes), the process proceeds to Step SA 8 ; if lower than 0 (No), the process returns to Step SA 2 . (Step SA 12 ) The counted value c in the preset counter 61 is incremented by one. (Step SA 13 ) Whether or not the current counted value c is lower than the maximum number C of successive open states set in Step SA 1 is determined. If the counted value c is lower than the maximum number C of successive open states (Yes), the process returns to Step SA 9 ; if equal to or higher than the maximum number C of successive open states (No), the process returns to Step SA 2 .
Referring next to FIGS. 6-7B , a second embodiment of the power supply device for electric discharge machining according to the present invention will be described.
When voltages of the same polarity are successively applied, the machining gap voltage may rise stepwise and converge to a final value, preventing individual waveforms of the applied voltages from becoming uniform, as shown in FIG. 7A . This problem does not occur in a case where each voltage application period of the voltage applying means is long enough to allow the machining gap voltage to become equal to the DC power supply voltage output from the machining power supply. Since the voltage application period is typically set to a short value to increase the electric discharge frequency, the voltage is turned off before the machining gap voltage reaches the DC power supply voltage, which causes the machining gap voltage to rise stepwise as in FIG. 7A and reach a final convergent value, which is the DC power supply voltage.
To solve this problem, in the present embodiment, a maximum machining gap voltage 93 lower than the DC power supply voltage is set in advance for each voltage value setting of the DC voltage source, as shown in FIG. 6 , and the absolute value of the machining gap voltage 91 and the maximum machining gap voltage 93 are compared with each other in the comparator 97 . The output from the comparator 97 is kept high while the absolute value of the machining gap voltage 91 is lower than the maximum machining gap voltage 93 .
In the power supply device for electric discharge machining in FIG. 6 , the output from the comparator 97 and a switching command 95 are input to the AND gate 67 (corresponding to the AND gates 67 X, 67 Y in the power supply device for electric discharge machining in FIG. 1 ). When the absolute value of the machining gap voltage 91 exceeds the maximum machining gap voltage 93 , the output from the comparator 97 becomes low and is input to the AND gate 67 . The output from the AND gate 67 is input to the driver circuit 69 (corresponding to the driver circuits 69 X, 69 Y in the power supply device for electric discharge machining in FIG. 1 ) and causes the driver circuit 69 to operate to forcibly turn off the switching elements in the voltage applying means.
Since the switching command is forcibly turned off when the maximum machining gap voltage is exceeded, the machining gap voltage does not exceed the maximum machining gap voltage and the waveforms of the voltages applied in individual cycles becomes identical, as shown in FIG. 7B .
Referring next to FIGS. 8 and 9 , a third embodiment of the power supply device for electric discharge machining according to the present invention will be described.
Generally, the electric discharge frequency and machining current during machining are not constant but always vary depending on the machined shape and the machining state. Since the machining conditions are usually determined such that the maximum current during machining does not exceed the rated current of the power supply, some reserves remain at many places with respect to the rated current of the power supply. Accordingly, if voltage application is temporarily stopped when the machining current reaches the rated current of the power supply, machining can be performed constantly at the rated current, which substantially enhances the machining capability.
Referring now to FIGS. 8 and 9 , the configuration and operation of the power supply device in this embodiment will be described more specifically. Although only the circuit on the positive polarity side is shown in these figures, the circuit on the negative polarity side can be controlled in the same way.
An average machining current k is determined by measuring the machining current with a current detector 213 and passing the measured signal through a low-pass filter 215 . The average machining current k and the rated machining current 217 , which is preset in the machining power supply circuit, are compared with each other in the comparator 219 . When the average machining current k exceeds the rated machining current 217 , the output l from the comparator reverses and triggers a one-shot pulse generator 223 . The output m from the one-shot pulse generator 223 is normally high, but with the trigger input, the output m from the one-shot pulse generator 223 stays low for a predetermine time period. Logic operation AND of the output m from the one-shot pulse generator 223 and a switching-on command a from the voltage application timing generator 221 are executed in the AND gate, so that the voltage application across the machining gap can temporarily be stopped. Here, the output from the AND gate 67 X in FIG. 1 becomes the output from the voltage application timing generator 221 in FIG. 8 . This can prevent the output current from the voltage application circuit from exceeding the rated current. | In a power supply device for electric discharge machining, the polarity of the voltage to be applied is determined on the basis of a result of determination whether the machining gap is in open state or not, an average value of voltages applied across the machining gap voltage during machining, and the number of successive open states with the same polarity. This eliminates the need to significantly vary the voltages to be applied from positive to negative and from negative to positive, thereby reducing the output energy required by the machining power supply. | 1 |
BACKGROUND OF THE INVENTION
The invention relates to a method for controlling a converter having at least two phase modules, which each have an upper and a lower valve branch, which each have at least two series-connected two-pole subsystems, with a constant, freely variable number of subsystems of each phase module being operated such that their terminal voltages are in each case equal to a capacitor voltage across the energy storage capacitor in the associated subsystem, with the remaining subsystems of this phase module being operated such that their terminal voltages are equal to zero.
A polyphase converter is known from DE 101 03 031 A1. FIG. 1 illustrates a circuit arrangement of a converter such as this, in more detail. According to this circuit arrangement, this known converter circuit has three phase modules, which are each annotated 100 . These phase modules 100 are each electrically conductively connected on the DC voltage side by a respective connection P or N to a positive and a negative DC voltage busbar P 0 and N 0 . There is a DC voltage U d between these two DC voltage busbars P 0 and N 0 . Each phase module 100 has an upper and a lower valve branch T 1 , T 3 and T 5 , as well as T 4 and T 6 , respectively. Each of these valve branches T 1 to T 6 has a number of two-pole subsystems 11 which are electrically connected in series. Four of these subsystems 11 are shown for each valve branch T 1 , . . . , T 6 in this equivalent circuit. Two-pole subsystems 12 ( FIG. 3 ) can also be electrically connected in series instead of the two-pole subsystems 11 ( FIG. 2 ). Each junction point between two valve branches T 1 and T 2 , T 3 and T 4 or T 5 and T 6 of a phase module 100 forms a respective connection L 1 , L 2 or L 3 of this phase module 100 on the AC voltage side. Since, in this description, the converter has three phase modules 100 , a three-phase load, for example a three-phase motor, can also be connected to their connections L 1 , L 2 and L 3 , which are also referred to as load connections, on the AC voltage side.
FIG. 2 shows one embodiment of a two-pole known subsystem 11 in more detail. The circuit arrangement shown in FIG. 3 represents a functionally completely equivalent variant, which is likewise known from DE 101 03 031 A1. These known two-pole subsystems 11 and 12 each have two semiconductor switches 1 , 3 and 5 , 7 which can be switched off, two diodes 2 , 4 and 6 , 8 , and a unipolar energy storage capacitor 9 and 10 . The two semiconductor switches 1 and 3 , as well as 5 and 7 , respectively, which can be switched off are electrically connected in series, with these series circuits being connected electrically in parallel with a respective energy storage capacitor 9 or 10 . One of the two diodes 2 , 4 and 6 , 8 is electrically connected in parallel with each semiconductor switch 1 and 3 , or 5 and 7 , respectively, which can be switched off such that these diodes 2 , 4 and 6 , 8 are electrically connected back to back in parallel with the corresponding semiconductor switches 1 , 3 , 5 or 7 which can be switched off. The unipolar energy storage capacitor 9 or 10 in the respective subsystem 11 or 12 comprises either a capacitor or a capacitor bank composed of a plurality of such capacitors with a resultant capacity C 0 . The connecting point of the emitter of the respective semiconductor switch 1 or 5 which can be switched off and the anode of the respective diode 2 or 6 forms a connecting terminal X 1 of the respective subsystem 11 or 12 . The connecting point of the two semiconductor switches 1 and 3 which can be switched off and of the two diodes 2 and 4 form a second connecting terminal X 2 of the subsystem 11 . The connecting point of the collector of the semiconductor switch 5 which can be switched off and the cathode of the diode 6 forms a second connecting terminal X 2 of the subsystem 12 .
In both illustrations of the embodiments of the two subsystems 11 and 12 , as illustrated in FIGS. 2 and 3 , insulated gate bipolar transistors (IGBTs) are used as semiconductor switches 1 , 3 and 5 , 7 which can be switched off. Furthermore, MOS field-effect transistors, also referred to as MOSFETs, can be used. Gate turn-off thyristors (GTO thyristors) or integrated gate commutated thyristors (IGCTs) can likewise be used as semiconductor switches 1 , 3 and 5 , 7 which can be turned off.
According to DE 101 03 031 A1, the respective subsystems 11 and 12 of each phase module 100 of the polyphase converter shown in FIG. 1 can be controlled in a switching state I, II or III, respectively. In the switching state I, the respective semiconductor switch 1 or 5 which can be turned off is switched on, and the respective semiconductor switch 3 or 7 which can be turned off in the subsystem 11 or 12 is switched off. This results in a terminal voltage U X21 , at the connecting terminals X 1 and X 2 , in the respective subsystem 11 or 12 being equal to zero. In the switching state II, the respective semiconductor switch 1 or 5 which can be turned off is switched off, and the respective semiconductor switch 3 or 7 which can be turned off in the subsystem 11 or 12 is switched on. In this switching state II, the terminal voltage U X21 that occurs is equal to the capacitor voltage U C across the respective energy storage capacitor 9 or 10 . In the switching state III, both the respective semiconductor switches 1 , 3 and 5 , 7 which can be turned off are switched off, and the capacitor voltage U C across the respective energy storage capacitor 9 or 10 is constant.
FIG. 4 shows a circuit arrangement of a further embodiment of a subsystem 14 , in more detail. This two-pole subsystem 14 was registered in a prior national patent application with the official file reference 2005P12105 DE, and has four semiconductor switches 21 , 23 , 25 and 27 which can be turned off, four diodes 22 , 24 , 26 and 28 , two unipolar capacitors 29 and 30 and electronics 32 , also referred to in the following text as the electronic assembly 32 . The four semiconductor switches 21 , 23 , 25 and 27 which can be turned off are connected electrically in series. Each of these semiconductor switches 21 , 23 , 25 and 27 has a diode 22 , 24 , 26 and 28 electrically connected back-to-back in parallel with it. One respective unipolar capacitor 29 or 30 is electrically connected in parallel with two respective semiconductor switches 21 , 23 and 25 , 27 which can be turned off. The respective unipolar capacitor 29 or 30 in this subsystem 14 comprises either a capacitor or a capacitor bank composed of a plurality of such capacitors with a resultant capacitance C 0 . The connecting point of the two semiconductor switches 21 and 23 which can be turned off and of the two diodes 22 and 24 forms a second connecting terminal X 2 of the subsystem 14 . The connecting point of the two semiconductor switches 25 and 27 which can be turned off and of the two diodes 26 and 28 forms a first connecting terminal X 1 of this subsystem 14 . The connecting point of the emitter of the semiconductor switch 23 which can be turned off, of the collector of the semiconductor switch 25 which can be turned off, of the anode of the diode 24 , of the cathode of the diode 26 , of the negative connection of the unipolar capacitor 29 and of the positive connection of the unipolar capacitor 30 forms a common potential which is electrically conductively connected to a reference-ground potential connection M of the electronics assembly 32 . This electronics assembly 32 is linked for signalling purposes by means of two optical waveguides 34 and 36 to a higher-level converter control system, which is not illustrated in any more detail. The common potential is used as a reference ground potential for the electronics assembly 32 .
This subsystem 14 can be controlled in four switching states I, II, III and IV. In the switching state I, the semiconductor switches 21 and 25 which can be turned off are switched on, and the semiconductor switches 23 and 27 which can be turned off are switched off. In consequence, the terminal voltage U X21 at the connecting terminals X 2 and X 1 in the subsystem 14 is equal to the capacitor voltage U C across the capacitor 29 . In the switching state II, the semiconductor switches 21 and 27 which can be turned off are switched on while, in contrast, the semiconductor switches 23 and 25 which can be turned off are switched off. The terminal voltage U X21 of the subsystem 14 now corresponds to the sum of the capacitor voltages U C across the unipolar capacitors 29 and 30 . In the switching state III, the semiconductor switches 23 and 25 which can be turned off are switched on, and the semiconductor switches 21 and 27 which can be turned off are switched off. In this switching state, the terminal voltage U XZ1 of the subsystem 14 is equal to 0. In the switching state IV, the semiconductor switches 23 and 27 which can be turned off are switched on while, in contrast, the semiconductor switches 21 and 25 which can be turned off are switched off. In consequence, the terminal voltage U X21 of the subsystem 14 changes from the potential level “zero” to the potential level “capacitor voltage U C ” which is the voltage across the unipolar capacitor 30 . In the switching states I and IV, the respective energy store 29 or 30 receives or emits energy depending on the terminal current direction. In the switching state III, the capacitors 29 and 30 receive or emit energy depending on the terminal current direction. In a switching state III (“zero”), the energy in the capacitors 29 and 30 remains constant. This subsystem 14 according to the invention therefore corresponds, in terms of its functionality, to the known subsystem 11 being connected in series with the known subsystem 12 .
The maximum number of respective energy stores 9 and 10 which can in fact be connected in series between a positive terminal P and the connection Lx, where x=1, 2, 3, on the AC voltage side of each phase module 100 of the polyphase converter as shown in FIG. 1 is referred to as the series operating cycle n. The maximum number of respective energy stores 9 and 10 which are actually connected in series between a positive terminal p and the connection Lx, where x=1, 2, 3, on the AC voltage side is reached when all the subsystems 11 , 12 and/or all the subsystems 14 of this valve branch T 1 , T 3 or T 5 have been switched to the switching state II (U 11 =n·U C and U 21 =n·U C and U 31 =n·U C , respectively). It is advantageous, but not absolutely essential, to provide the same series operating cycle n between the connection Lx on the AC voltage side and a negative terminal N of each phase module 100 . The subsystems 11 and 12 shown in FIGS. 2 and 3 have a respective energy storage capacitor 9 or 10 , while the subsystem 14 shown in FIG. 4 contains two energy storage capacitors 29 and 30 . This therefore results in a series operating cycle of n=4 for the polyphase converter shown in FIG. 1 , when four subsystems 11 and 12 are electrically connected in series in each case between the positive terminal P and the connection Lx, on the AC voltage side of each phase module 100 . However, if four subsystems 14 as shown in FIG. 4 are connected in series between the positive terminal P and the connection Lx on the AC voltage side of each phase module 100 , then this results in a series operating cycle of n=8, since eight energy stores 29 and 30 can then be electrically connected in series. In applications in the field of power distribution, a polyphase converter such as this with distributed energy stores for each phase module 100 has at least 20 energy storage capacitors 9 , 10 or 29 , 30 connected electrically in series. Converters such as these are used for high-voltage direct-current transmission systems (HVDC system) or for flexible AC transmission systems, so-called FACTS.
The following explanatory notes are based on the assumption that all the energy stores in the subsystems 11 , 12 or 14 of each valve branch T 1 , T 2 : T 3 , T 4 or T 5 , T 6 , respectively, of each phase module 100 of the polyphase converter and shown in FIG. 1 each have the same capacitor voltage U C . Methods for initial production of this state and for maintaining it during operation of a converter such as this are known from DE 101 03 031 A1.
FIG. 5 shows an electrical equivalent circuit of the polyphase converter shown in FIG. 1 . In this electrical equivalent circuit, the individual equivalent circuit components of each subsystem of a valve branch T 1 . . . , T 6 are combined to form an electrical equivalent circuit of one valve branch T 1 , . . . , T 6 .
In general, it is advantageous to design the polyphase converter such that, averaged over time, a suitable number of the systems 11 , 12 and/or 14 are always being operated, such that the sum of their terminal voltages is given by: ΣU X21 =n·U C (switching state II). This corresponds to precisely half of the energy stored in the series-connected subsystems 11 , 12 and/or 14 , and leads to a mean intermediate-circuit voltage of U d =n·U C . This corresponds to a drive level b on the DC voltage side of 0.5, with the drive level b representing the ratio of the actual intermediate-circuit voltage U d to the maximum possible intermediate-circuit voltage U dmax . This drive level is calculated using the following equation:
b
=
U
d
U
d
max
=
U
d
2
·
n
·
U
c
(
1
)
Equivalent capacitance value of each valve branch T 1 , . . . , T 6 , averaged over time, is therefore C/m, where m=n/2. In order to prevent large uncontrolled equalizing currents flowing through the DC voltage busbars P 0 and N 0 between the individual phase modules 100 of the polyphase converter with distributed energy stores, the same nominal value is generally predetermined in each case between the terminals P and N of each phase module 100 for the respective voltages U 11 , U 12 , and U 21 , U 22 , and U 31 , U 32 and this means that:
U 11 +U 12 =U 21 +U 22 =U 31 +U 32 =U d . (2)
If the respective semiconductor switches 1 , 3 ; 5 , 7 and 21 , 23 , 25 , 27 of all the phase modules 100 of the polyphase converter with distributed energy stores are operated in a balanced form, then, for balancing reasons, the arithmetic mean values of the valve branch currents i 11 , i 12 , i 21 , i 22 , i 31 and i 32 become:
ī 11 =ī 12 ī 21 ī 22 =ī 31 =ī 32 =⅓· I d . (3)
Because of the effective impedances of the phase modules 100 of the polyphase converter when the phases are being operated and loaded in a balanced form, these values are passive. The time profiles of the valve branch currents i 11 (t), i 12 (t), i 21 (t), i 22 (t), i 31 (t) and i 32 (t) therefore correspond to the following equations:
i 11 ( t )˜⅓ ·I d +½ ·i L1 ( t ),
i 12 ( t )˜⅓ ·I d +½ ·i L1 ( t ),
i 21 ( t )˜⅓· I d +½ ·i L2 ( t ),
i 22 ( t )˜⅓ ·I d +½ ·i L2 ( t ),
i 31 ( t )˜⅓ ·I d +½ ·i L3 ( t ),
i 32 ( t )˜⅓ ·I d −½ ·i L3 ( t ), (4)
According to these equations, the valve branch currents i 11 (t), i 12 (t), i 21 (t), i 22 (t), i 31 (t) and i 32 (t) each have corresponding fundamental profiles comprising a DC component ⅓· and an AC component which corresponds to half the output current i Lx (t). This combination results from the balanced operation and the identical impedances, resulting from this, in all the valve branches T 1 , . . . , T 6 ( FIG. 5 ).
In order to ensure the passive setting of these valve branch currents i 11 (t), i 12 (t), i 21 (t), i 22 (t), i 31 (t) and i 32 (t) the following rules should be observed with regard to the operation of the semiconductor switches 1 , 3 ; 5 , 7 and 21 , 23 , 25 , 27 which can be turned off in a respective subsystem 11 , 12 or 14 :
Within one phase module 100 , care should always be taken to ensure that a constant number of energy stores in the subsystems 11 , 12 and/or 14 are connected in series at any given time.
This means that, when a switching state change occurs from the switching state I to the switching state II in any given subsystem 11 or 12 , or a change from the switching state I to II; IV to II; III to IV or III to I in any given subsystem 14 , or from the switching state II to the switching state I in any given subsystem 11 or 12 , or a change occurs from the switching state II to I; II to IV; IV to III or I to III in any given subsystem 14 in an upper or lower respective valve branch T 1 , T 3 , T 5 or T 2 , T 4 , T 6 of a phase module 100 , a corresponding switching state change must also take place from the switching state II to the switching state I of any given subsystem 11 or 12 or a change from the switching state II to I; II to IV; IV to III or I to III of any given subsystem 14 or from the switching state I to the switching state II of any given subsystem 11 or 12 or a change from the switching state I to II; IV to II; III to IV or III to I of any given subsystem 14 in a lower or upper respective valve branch T 2 , T 4 , T 6 or T 1 , T 3 , T 5 . With a drive level b of 0.5 on the DC voltage side, this means that the subsystems 11 , 12 and/or 14 of a phase module 11 must always be switched such that n and only n energy stores in the subsystems 11 , 12 and/or 14 are actually connected in series (U d =n·U C ).
If this condition is not satisfied, then this leads to undesirable and uncontrolled equalizing currents between the phase modules 100 of the polyphase converter with distributed energy stores as shown in FIG. 1 . These equalizing currents are excited by a voltage/time integral ΔU ph , which can be calculated using the following equation:
Δ U ph =k·U C ·ΔT (5)
In this case, ΔT is a difference time interval which can occur when a switching state change occurs. This difference time interval ΔT is very much less than 1 μs. The factor k is a constant indicating the difference between the number of energy stores actually connected in series in the subsystems 11 , 12 and/or 14 and the series operating cycle n. If the drive level b on the DC voltage side is 0.5, then: −n≦k≦n. The equalizing currents which are excited by this voltage/time integral ΔU ph can be calculated using the electrical equivalent circuit shown in FIG. 5 . In order to prevent high voltage/time integrals ΔU ph resulting in the excitation of high equalizing currents, the drive for the polyphase converter with distributed energy stores should be designed such that only one or only a small number of subsystems 11 , 12 and/or 14 of one valve branch T 1 , . . . , T 6 can have their switching states changed at any one time.
This measure limits the constant k to low values.
Basic profiles of the valve branch voltages U x1 and U x2 , where x=1, 2, of an upper respective valve branch T 1 , T 3 or T 5 and a lower respective valve branch T 2 , T 4 or T 6 of a phase module 100 of a polyphase converter with distributed energy stores are each illustrated, by way of example, in a graph plotted against time t in FIGS. 6 and 7 . The graph in FIG. 8 shows the profile of the sum of the two valve branch voltages U x1 and U x2 plotted against time t. In accordance with the control method described above, the sum of the two valve branch voltages U x1 and U x2 is always constant and corresponds to the intermediate-circuit voltage U d . The switching operations illustrated in FIGS. 6 and 7 are required in order to allow the illustrated profile of the valve branch voltages U x1 and U x2 to be set. These valve branch voltages U x1 and U x2 of a phase module 100 are controlled by a higher-level control system.
According to the known control method, when the number of energy stores which are actually connected in series in the upper respective valve branch T 1 , T 3 or T 5 is changed, a corresponding number of subsystems 11 , 12 and/or 14 in the lower respective valve branch T 2 , T 4 or T 6 have their switching state changed such that, in each phase module 100 , a constant number n of energy stores are still connected in series in the subsystems 11 , 12 and/or 14 for a drive level b of 0.5 on the DC voltage side. This results in a constant DC voltage of U d =n·U C .
If this known method is used in all the parallel-connected phase modules 100 of the polyphase converter with distributed energy stores, this generally leads to there being no significant equalization processes in the form of equalizing currents between these phase modules 100 . However, this is also dependent on the impedance relationships illustrated in FIG. 5 .
SUMMARY OF THE INVENTION
The invention is now based on the idea of being able to influence the valve branch currents i 11 , i 12 , i 21 , i 22 , i 31 and i 32 differently from their passively set profile.
In principle, additional valve branch currents i Zxy (t) can be set and controlled as required in each valve branch T 1 , T 2 ; T 3 , T 4 or T 5 , T 6 , respectively, in a time profile for a valve branch current i 11 (t), i 12 (t), i 21 (t), i 22 (t), i 31 (t) and i 32 (t). These additional valve branch currents i Zxy (t) result in the time profiles of the valve branch currents, according to equation system ( 4 ), becoming:
i 11 ( t )=⅓ ·I d +½ ·i L1 ( t )+ i Z11 ( t ),
i 12 ( t )=⅓ ·I d +½ i L1 ( t )+ i Z12 ( t ),
i 21 ( t )=⅓ ·I d +½ ·i L2 ( t )+ i Z21 ( t ),
i 22 ( t )=⅓ ·I d +½ ·i L2 ( t )+ i Z22 ( t ),
i 31 ( t )=⅓ ·I d +½ ·i L3 ( t )+ i Z31 ( t ),
i 32 ( t )=⅓ ·I d +½ ·i L3 ( t )+ i Z32 ( t ) (6)
In order to ensure that the output currents i Lx (t) do not change, the additional valve branch currents i Zxy (t) are set such that the additional valve branch currents i Zxy (t) of each phase module 100 are the same. This means that:
i Z11 ( t )= i Z12 ( t ),
i Z12 ( t )= i Z22 ( t ), (7)
i Z31 ( t )=i Z32 ( t ),
The invention is now based on the object of developing the known control method for a polyphase converter with distributed energy stores such that predetermined additional valve branch currents occur.
According to one aspect of the invention, this object is achieved by a method for controlling a polyphase converter having at least two phase modules, which have an upper and a lower valve branch, which each have at least two series-connected two-pole subsystems, with switching operations in the upper valve branch and corresponding switching operations in the lower valve branch of each phase module being carried out with a freely variable time interval between them.
According to another aspect of the invention this object is achieved by a method for controlling a polyphase converter having at least two phase modules, which each have an upper and a lower valve branch, which each have at least two series-connected two-pole subsystems, with at least two further switching operations, which are offset with respect to one another for a predetermined time interval, being carried out between time-synchronized switching operations in the upper and lower valve branch of each phase module ( 100 ), in an upper and/or a lower valve branch of each phase module.
Since additional voltage/time integrals are used in the valve branch voltages of a phase module as a manipulated variable to influence the valve branch currents, the valve branch currents can be influenced deliberately.
Voltage/time integrals such as these are produced, according to the invention, by the switching operations in the two valve branches of each phase module of the polyphase converter with distributed energy stores no longer being carried out synchronized in time, but with a freely variable time interval.
Voltage/time integrals such as these are also produced according to the invention by providing a further switching operation between the switching operations which are synchronized in time.
These further switching operations can be carried out in an upper and/or a lower valve branch of each phase module of the polyphase converter with distributed energy stores. This results in a balanced drive at the times of the additional switching operations in the upper and/or lower valve branches of each phase module of the polyphase converter with distributed energy stores.
In one advantageous method, the switching operations of an upper valve branch of a phase module are carried out delayed and/or advanced with respect to switching operations of a lower valve branch of this phase module. This allows a predetermined additional voltage/time integral to be set dynamically over one period of the valve branch voltages of a phase module.
In a further advantageous method, the two methods are combined with one another in order to generate additional voltage/time integrals. This means that a required predetermined voltage/time integral can be generated at any desired time.
A valve branch current can in each case be calculated as a function of the additional voltage/time integrals in conjunction with the electrical equivalent circuit of the valve branches of the polyphase converter with distributed energy stores. If the valve branch currents of the individual phase modules of the polyphase converter with distributed energy stores are measured, then an additional voltage/time integral can be determined at any time, ensuring that the existing valve branch currents are changed such that equalizing currents can no longer flow between the phase modules of the polyphase converter with distributed energy stores.
The use of the control method according to the invention results in dynamic control of the valve branch currents of a polyphase converter with distributed energy stores. Inter alia, this use results in a number of advantages:
damping of current oscillations, for example caused by:
transient load change processes faults, for example unbalances in a power supply system or a machine, ground faults, lightning strikes, switching overvoltages, . . . inadequate damping of capacitive networks by the inductances and resistances provided in the design.
Faults coped with better. Poor operating points coped with such as:
operating points at low output frequencies.
Capabilities to optimize the design of the subsystems and of the polyphase converter in terms of capacitor complexity and the need for power semiconductors. A uniform load ensured on all semiconductor switches which can be turned off. Balancing of highly unbalanced voltage on the individual converter elements after fault disconnection.
BRIEF DESCRIPTION OF THE DRAWING
The rest of the explanation of the invention refers to the drawing, which schematically illustrates a plurality of embodiments of one method according to the invention for controlling a polyphase converter with distributed energy stores, and in which:
FIG. 1 shows a circuit arrangement of a known converter with distributed energy stores,
FIGS. 2 to 4 each show a circuit arrangement of one embodiment of a known subsystem,
FIG. 5 shows an electrical equivalent circuit of the valve branches of the converter shown in FIG. 1 ,
FIGS. 6 and 7 each use a graph plotted against time t to show a valve branch voltage of an upper and lower valve branch of a phase module of the known converter shown in FIG. 1 ,
FIG. 8 uses a graph plotted against time t to show the sum voltage of the two valve branch voltages shown in FIGS. 6 and 7 ,
FIGS. 9 and 10 each use a graph plotted against time t to show the valve branch voltages of a phase module of the converter shown in FIG. 1 , when using a first embodiment of the control method according to the invention,
FIG. 11 uses a graph plotted against time t to show the sum voltage of the two valve branch voltages shown in FIGS. 9 and 10 ,
FIGS. 12 and 13 each use a graph plotted against time t to show valve branch voltages of a phase module of the converter shown in FIG. 1 when using a second embodiment of the control method according to the invention,
FIG. 14 uses a graph plotted against time t to show the associated sum voltage,
FIGS. 15 and 16 each use a graph plotted against time t to show a valve branch voltage of a phase module of the converter shown in FIG. 1 , with these being the valve branch voltages which occur when using a combination of the two embodiments of the control method according to the invention, and
FIG. 17 shows a graph plotted against time t of the associated sum voltage.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The graph in FIG. 9 shows the profile of a valve branch voltage U x1 of an upper valve branch T 1 , T 3 and T 5 of a phase module 100 of the converter shown in FIG. 1 , plotted against time t. The time profile of a valve branch voltage U x2 of a lower valve branch T 2 , T 4 or T 6 of this phase module 100 is illustrated in more detail in the graph in FIG. 10 . The sum voltage of these two valve branch voltages U x1 and U x2 of a phase module 100 of the converter shown in FIG. 1 is illustrated, plotted against time t, in the graph in FIG. 11 . If this sum voltage is compared with the sum voltage in FIG. 8 , it is evident that the sum voltage shown in FIG. 11 has additional voltage/time integrals ΔU ph1 , . . . , ΔU ph4 . These additional voltage/time integrals ΔU ph1 , . . . , ΔU ph4 occur because the switching operations in the upper and lower respective valve branches T 1 and T 2 ; T 3 and T 4 as well as T 5 and T 6 of a phase module 100 are no longer carried out synchronized in time. Any given subsystem 11 , 12 changes from the switching state I to the switching state II at the time t 1 , or any given subsystem 14 in the lower respective valve branch T 2 , T 4 or T 6 of the phase module 100 changes from the switching state I to II or IV to II, or III to IV, or III to I at the time t 1 in comparison to the change of the switching state II to the switching state I of any given subsystem 11 , 12 or the change from the switching state II to I, II to IV, IV to III, or I to III of any given subsystem 14 in the upper respective valve branch T 1 , T 3 or T 5 of this phase module 100 , delayed by a time interval ΔT 1 . The additional voltage/time integral ΔU ph1 resulting from this is calculated using the following equation:
Δ U ph =k·U C ·ΔT Z (8)
In this case, the factor k indicates the difference between the energy stores (in the switching state II in subsystems 11 , 12 and in the switching state I or II or IV in the subsystem 14 ) which are actually connected in series and through which current passes during the time interval ΔT Z , and the series operating cycle n. In this example, the series operating cycle is n=4. This results in a factor of k=−1 for the time interval ΔT 1 . At the time t 4 , any given subsystem 11 , 12 changes from the switching state I to the switching state II, or any given subsystem 14 in the upper valve branch T 1 , T 3 or T 5 changes from the switching state I to II, IV to II, III to IV, or III to I, with an advance corresponding to the time interval ΔT 2 with respect to any given subsystem 11 , 12 changing from the switching state II to the switching state I or any given subsystem 14 in the lower valve branch T 2 , T 4 , or T 6 changing from the switching state II to I, II to IV, IV to III or I to III. The factor is therefore k=+1 during the time interval ΔT 2 . The magnitude of the additional voltage/time integrals ΔU ph1 , . . . , ΔU ph4 can be determined using the freely variable time interval ΔT Z . The mathematical sign of the additional voltage/time integral ΔU ph and therefore the mathematical sign of an additional valve branch current i Zxy (t) are determined by means of the factor k. The additional valve branch current i Zxy (t) can be varied by generating a plurality of additional voltage/time integrals ΔU ph distributed over the period of the fundamental frequency of the valve branch voltage U x1 or U x2 , respectively, of a respective upper or lower valve branch T 1 , T 3 , T 5 or T 2 , T 4 , T 6 . The valve branch currents i xy (t) can be dynamically controlled by means of this method according to the invention for controlling a polyphase converter with distributed energy stores as shown in FIG. 1 .
The graph in FIG. 12 shows the profile of a valve branch voltage U x1 of an upper valve branch T 1 , T 3 or T 5 of a phase module 100 of a converter shown in FIG. 1 . The profile of a valve branch voltage U x2 of a corresponding respective valve branch T 2 , T 4 or T 6 of this phase module 100 is plotted against time t in the graph in FIG. 13 . The associated sum voltage of these two valve branch voltages U x1 and U x2 is illustrated plotted against time t in the graph in FIG. 14 . These two valve branch voltages U x1 and U x2 differ from the two valve branch voltages U x1 and U x2 shown in FIGS. 6 and 7 by additional switching operations being carried out in addition to the switching operations that are synchronized in time. Two switching operations have been inserted in the profile of the valve branch voltage U x1 in the time period t 2 -t 1 , resulting in connection of a further respective subsystem 11 or 12 or a further energy store of a subsystem 14 of the respective upper valve branch T 1 , T 3 or T 5 of a phase module 100 for a time interval ΔT 1 . Further switching operations such as these are carried out in the time period t 5 -t 4 for a time interval ΔT 2 . Two switching operations have been inserted in the profile of the valve branch voltage U x2 in the time period t 8 -t 7 . These switching operations result in two respective subsystems 11 and 12 or two respective energy stores in the subsystems 14 being turned off for a time interval ΔT 3 in the lower valve branch T 2 , T 4 or T 6 , respectively, of a phase module 100 . In the time period t 11 -t 10 , respective further switching operations are carried out in the upper and lower valve branch T 1 , T 3 , T 5 and T 2 , T 4 , T 6 . As a result of these switching operations, a respective subsystem 11 or 12 or an energy store in a subsystem 14 of a phase module 100 is turned off for this time interval ΔT 4 in the upper respective valve branch T 1 , T 3 or T 5 and a respective subsystem 11 or 12 or an energy store in a subsystem 14 is likewise turned off for the same time interval ΔT 4 in the lower respective valve branch T 2 , T 4 or T 6 . These further switching operations in the upper and/or lower valve branches T 1 , T 3 , T 5 and/or T 2 , T 4 , T 6 result in additional voltage/time integrals ΔU ph1 , . . . , ΔU ph4 being generated, which each generate additional valve branch currents i Zxy (t) in the respective valve branches T 1 , T 2 ; T 3 , T 4 or T 5 , T 6 of each phase module 100 of the converter shown in FIG. 1 . These additional voltage/time integrals ΔU ph1 , . . . , ΔU ph4 can be obtained from the sum voltage of the two valve branch voltages U x1 and U x2 . The magnitude of these additional voltage/time integrals ΔU ph1 , . . . , ΔU ph4 depends on which additional valve branch currents i Zxy (t) are required in the respective valve branches T 1 , T 2 ; T 3 , T 4 or T 5 , T 6 of each phase module 100 . These additional voltage/time integrals ΔU ph1 , . . . , ΔU ph4 are calculated using the equation (7). The additional voltage/time integrals ΔU ph1 , . . . , ΔU ph4 obtained from this can also be distributed over time over one period of the fundamental frequency of the valve branch voltage U x1 or U x2 , respectively, in the method for additionally introduced switching operations.
A combination of the methods for producing additional voltage/time integrals ΔU ph1 , . . . , ΔU ph4 by delayed and/or advanced switching operations with additional switching operations leads to the profiles of the valve branch voltages U x1 and U x2 of an upper and lower respective valve branch T 1 , T 2 ; T 3 , T 4 or T 5 , T 6 of a phase module 100 of the converter shown in FIG. 1 . These valve branch voltages U x1 and U x2 are respectively shown in a graph plotted against time t in FIGS. 15 and 16 . An associated sum voltage of these valve branch voltages U x1 and U x2 plotted against time is illustrated in the graph in FIG. 17 . | The invention relates to a method for controlling a power converter comprising at least two phase modules, each of which is provided with an upper and a lower valve leg that is equipped with at least two serially connected bipolar subsystems, respectively. According to the invention, the switching actions in the two valve legs (T 1 , T 2 ; T 3 , T 4 ; T 5 , T 6 ) of each phase module ( 100 ) of the multiphase power converter having distributed energy stores are performed at a freely selected interval (ΔTZ) rather than synchronously. The inventive control method for a multiphase power converter having distributed energy stores thus makes it possible to dynamically regulate valve leg currents (i 11 , i 12 , i 21 , i 31 , i 32 ). | 7 |
This is a file wrapper continution of application Ser. No. 08/542,646, filed Oct. 13, 1995 now abandoned.
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates to a method of producing and treating chemical cellulose pulps so as to minimize the use of bleaching chemicals and/or to optimize bleaching sequences.
Pulp mills have recently attempted to abandon the use of elementary chlorine, and sometimes chlorine dioxide as well. The reasons for this appear to be both environmental and economical (market acceptance). Disadvantages caused by elementary chlorine include both considerable malodorous gaseous emissions and liquid effluents from chemical pulp mills into water systems. Chlorine dioxide does not cause odor problems as significant as those of chlorine, but discharges to waterways are a concern. When comparing these chlorine chemicals with each other by means of the AOX number designating the loading on water systems, elementary chlorine is many times more detrimental than chlorine dioxide.
During the past few years, a large number of chlorine-free bleaching methods have been developed, often using oxygen, ozone, and/or peroxide. However, in many countries sequences using chlorine dioxide are also popular because the price of chlorine dioxide is very competitive compared with that of other chemicals (today approximately half of the price of competing peroxide). Also the strength and brightness values achieved by chlorine dioxide bleaching are at least approximately of the same scale as those for hydrogen peroxide bleaching at the same consumption of chemical (kg/adt).
When bleaching of cellulose pulps is effected using oxygen, peroxide or ozone, removal of heavy metals is almost essential. Detrimental metals include manganese, copper and iron, which catalyze reactions harmful to the quality of pulp. They degrade bleaching chemicals, which decreases the efficiency of bleaching and increases the consumption of chemicals. In cellulose pulps, heavy metals are primarily bound to carboxyl acid groups.
It has been suggested that removal of metals be effected in such a way that prior to the critical bleaching stage, pulp is pre-treated with an acid, e.g. sulphuric acid. Published Canadian patent application 1206704 discloses that the acid treatment is carried out at a temperature of at least 50° C., preferably at 60 to 80° C., at pH 1 to 5. It is stated in the publication that even acid treatment at a lower temperature results in significant removal of detrimental metal ions, but acid treatment at the temperatures according to the publication modifies lignin so that dissolution thereof is significantly improved in alkaline peroxide treatment following the add treatment (Lachenal, D. et al., Tappi Proceedings, International Pulp Bleaching Conference, 1982, p. 145-161). Thus, the acid stage causes the kappa number to drop in the peroxide stage, whereas no decrease in the kappa number has been found in the acid stage. It is also stated that in theory, the acid treatment could be effected even at a temperature of 100° C., but this could result in pulp of poorer quality.
In published EP patent application 511695 it is suggested that after acid treatment, metal ions advantageous for peroxide bleaching, such as magnesium ions, should be added, since some of these desirable magnesium ions are removed in the acid treatment. According to this publication, the acid treatment is effected at a temperature of 10 to 95° C., most preferably at 40 to 80° C., and at pH 1 to 6, most preferably 2 to 4.
The acid treatment is followed by a stage in which suitable alkaline earth metal is added. Further, it is mentioned that during acid treatment, pulp can be treated with a suitable bleaching and/or delignification chemical, such as chlorine dioxide.
Removal of detrimental metals may be made more efficient by using chelating agents for binding metals in connection with the acid treatment. One such method is disclosed in the SE patent 501651, which brings forward an acid treatment similar to that in the above-mentioned EP publication 511695, with the difference being that acid treatment is effected in the presence of a chelating agent. However, chelating agents used for binding metals contribute to increased bleaching costs.
The primary aim of the above-described acid treatments of pulp is to achieve such a composition of metals which is preferable for chlorine-free bleaching chemicals. In these stages, the kappa number may be decreased by 1 to 2 units due to a washing and extraction phenomenon. As mentioned earlier, the metal composition affects the consumption of bleaching chemicals, the reason for the use of known acid stages being therefore removal of metals from the pulp.
One of the most important disadvantages of prior art bleaching is an undesirably large consumption of bleaching chemicals, especially chlorine-free ones, which significantly raises the production costs of bleached pulp. Also with chlorine dioxide bleaching there must be attempts to reduce the consumption of ClO 2 both for financial and environmental reasons. Further, a degree—in some cases a great degree—of brightness reversion is a typical feature of pulps bleached with oxygen and peroxide.
The invention seeks to eliminate or minimize the disadvantages of the prior art and to provide a totally new procedure for bleaching cellulose pulps, in particular cellulose pulps delignified under alkaline conditions, by means of either totally chlorine-free bleaching chemicals, or by using chlorine dioxide. The cellulose pulp produced according to the invention is easily bleached, e.g. by means of oxygen and/or peroxide.
It is known that cellulose pulps contain 4-O-methyl-α-D-glucuronic acid groups (glucuronic acid groups). According to the invention it has been discovered that sulphate pulps also contain, in addition to glucuronic acid groups, a significant amount of 4-deoxy-β-L-threo-hex-4-enopyranosyl uronic acid groups (i.e. hexenuronic acid groups) bound to xylan. The amount of hexenuronic acid in some pulps is even substantially greater than the amount of known glucuronic acid groups. The term “hexenuronic acid” as used in the present specification and claims encompasses all 4-deoxy-β-L-threo-hex-4-enopyranosyl uronic acid groups.
It has been discovered that in bleaching of pulp, hexenuronic acid consumes bleaching chemicals reacting electrophilically, such as chlorine, chlorine dioxide, ozone and peracids (Buchert et al., 3rd European Workshop on Lignocellulosics and Pulp, Stockholm, 28.-31.8.1994). However, the hexenuronic acid does not affect the consumption of oxygen and hydrogen peroxide used as bleaching chemicals in alkaline conditions, because they do not react with hexenuronic acid. Thus, no degradation of hexenuronic acid occurs in oxygen and/or peroxide bleaching. Instead, special problems of bleaching pulp with oxygen and/or peroxide are relatively low brightness, and/or a tendency of such pulps to undergo brightness reversion.
The invention is based on the concept that by selectively removing hexenuronic acid from cellulose pulps in connection with bleaching it is possible to reduce the consumption of bleaching chemicals. Surprisingly, it has been discovered that at the same time, the brightness reversion tendency of pulp decreases. Also, bleaching becomes more selective, since the heavy metals can be removed more efficiently.
The selective removal of hexenuronic acid according to the invention is effected in part by making the water suspensions of cellulose pulps slightly acidic—typically, the pH is set between about 2 and about 5—and by treating the water suspensions at an elevated (above ambient) temperature. To achieve a preferable result the temperature is at least about 85° C., most preferably at least about 90° C. Practical utilization of temperatures as high as this has previously been avoided in acid treatment, because it has been assumed that the quality of pulp would suffer. The primary purpose of acid treatment has been removal of detrimental metals. In above-described acid treatments, the purpose of which is removal of metals, the temperature does not play a significant role. What is significant is that the pH of the pulp is so low that metals separate from fibers. In laboratories the treatment is generally carried out at room temperature (20-25° C.). In mills removal of metals is typically effected at a temperature of between 60 to 85°C., which is the temperature prevailing naturally in the acid treatment stage due to water circulations. If a mill wished to practice acid treatment at a higher temperature for some reason, the acid treatment stage would have to be separately heated with steam or the like. This has naturally been avoided since it has been assumed that the strength qualities of the pulp would deteriorate. Therefore, according to what has been known so far, there has been no reason to use hot [over 85° C.] acid stages. The higher temperatures mentioned in the prior art (e.g. CA 1206704) only mean that removal of metals is also possible at higher temperatures.
Duration of the treatment does not play a significant role for removal of metals, except insofar as it is sufficiently long to allow metals separation, typically over 10 minutes. Extra time is not harmful for removal of metals but it naturally causes extra costs to the mill, since long treatment times require use of larger tanks. Large tanks have also been avoided because it has been feared that the acid stage would harm the strength qualities of the pulp. Thus, long treatment times in connection with add stages as mentioned in the prior art only mean that a long treatment time does not have a harmful effect on removal of metals.
In particular, it has to be noted that there have been definite reasons for avoidance of long and hot (e.g. 2 to 3 hours and 85° C.) acid treatments in mill conditions. These above-described reasons have been so significant that prior to the invention it has not been discovered that the kappa number of pulp can be decreased by 2 to 9, preferably 3 to 6, units by means of this kind of treatment. Not even in laboratory experiments has this been discovered, since the whole idea has been regarded as being contrary to all existing knowledge. What is especially surprising is that such acid treatment can be carried out without damaging the strength qualities of pulp, if the kappa number of the pulp to be treated has been made to drop sufficiently, i.e. under about 24, preferably under about 14, by cooking or possibly further delignification, despite the fact that pulp treatment with both acid (stage A) and chelating agents (stage Q) has been examined intensively during the last five years in connection with peroxide bleaching. Therefore, it is very surprising that a relatively long and hot acid stage is desirable when both a high temperature and a long time, even when used separately, have previously been regarded as detrimental factors in connection with acid treatment of pulp.
It should also be noted that pH in known acid treatments has to be rather low, i.e. 1.5-2, for decreasing e.g. the manganese content of the pulp considerably. In the pH range below 2, the carboxylic acid type groups become entirely protonated, resulting in low metal levels. Between pH 2 and 6, metal ions compete with hydrogen ions for the carboxyl acid sites, resulting in increasing metal levels as pH increases (Devenyns, J. et al., Tappi Pulping Conference Proceedings, 1994, 381-388; Bouchard, J. et al., International Pulp Bleaching Conference 1994, 33-39). On the other hand, in the method of the present invention the carboxyl acid type groups (hexenuronic aids) are removed, which means that the number of the carboxyl acid sites is decreased and the pulp can become occupied by metals to a lesser extent.
Practicing the invention it is possible to easily produce bleached cellulose pulp by means of a sulphate method or an equivalent alkaline method that forms hexenuronic acid in the pulp. It is characteristic of the pulp manufactured according to the invention that it contains at most only a small amount of hexenuronic acid, and can be easily bleached without chlorine (ECF) or chlorine-containing chemicals (TCF), or even with mere oxygen gas and/or peroxide. The consumption of bleaching chemicals can also be substantially reduced. Further, it is typical of the pulp produced in this way that, expressed as a pc-number, the brightness reversion thereof is smaller than 2.
The treatment of the pulp in a water suspension practiced according to the invention in acidic circumstances at a temperature of over 85° C. is hereafter also called “acidic pre-treatment”. According to the invention, cellulose pulp is treated in the presence of water at a temperature of at least 85° C. at a pH in the range from about 2 to about 5 (typically at a pH in the range from 2.0-5.0) in order to remove hexenuronic acid from the cellulose pulp. Preferably, the pH value of the water suspension of the cellulose pulp is maintained between 2.5 and 4.0. The lowest pH values (2.5 to 3.5) are preferable for softwood and the highest (3 to 4) for hardwood.
Various acids—inorganic acids, e.g. mineral acids such as sulphuric, nitric and hydrochloric acid, and organic acids such as formic and/or acetic acid—may be used to set the pH value for the pulp slurry. If so desired, the acids may be buffered, e.g. with the salts of the acids, such as formiates, in order to keep the pH value as even as possible during the treatment. There may be great variations in the temperature, ranging from just above 85° C. upwardly. Preferably, the temperature is kept at about 90 to 110° C. If the treatment is practiced under atmospheric conditions, 100° C. is a natural maximum limit, however even higher temperatures are possible if pressure vessels are used. Thus, the treatment may be effected in a bleaching tank under a pressure of about 200 to 500 kPa, at a temperature of about 110 to 130° C. To avoid excessive degradation of fiber, the maximum limit of the temperature is usually set to about 180° C. (unless chemicals or treatments can be provided which give temperature protection).
The duration of the treatment varies according to the pH value, the temperature, and the specific pulp treated. Naturally, it also depends on how complete the removal of hexenuronic acids is desired to be. In general, the treatment time is at least t minutes, where t=0.5 exp(10517/(T+273)−24) (t=0.5 exp(10517/(T+273)−24)). T is the temperature of the acid treatment in degrees C. The degradation of hexenuronic acid groups is in accordance with first-order reaction kinetics. It is known that the relation between reaction rate constant k and temperature T (degrees Kelvin) is k=A e −E/RT (Arrhenius Relationship), where A is the constant depending on the reaction in question, E the activation energy and R the gas constant. On the other hand it is known that for the first-order reaction the reaction time in minutes is t=(1/k)ln (c o /c), where c is the concentration of the hexenuronic acids and c o is the original concentration. By using the Arrhenius equation and t=(1/k)ln (c o /c) and test results (e.g. from Example 8 below) the equation of t=0.5 exp(10517/(T+273)−24) was obtained. In general t is between 5 minutes and 10 hours. In the examples described below, the treatment is practiced under atmospheric conditions. The typical treatment time at a temperature of 90° C. is about 1.5 to 6 hours, at 95° C. about 50 minutes to 5 hours, at 100° C. about 0.5 to 4 hours. Under pressure, e.g. at a temperature of 120 to 130° C., the treatment may be effected typically within about 5 to 50 minutes.
The intention is to remove as large a part of the hexenuronic acid as possible, preferably at least about 50%, especially preferably at least about 80%, and most suitably at least about 90% (e.g. about 90-97%). The concept “pulp contains at most a small amount of hexenuronic acid” means that the amount of hexenuronic acid is at most 50%, especially preferably at most 25%, and most suitably at most 10% of the amount which is present after cooking in corresponding pulp which has not been treated. To prevent excessive degradation of carbohydrate substance, no attempts are usually made to remove the hexenuronic acid completely, i.e., there is no attempt to remove more than about 97-99% of the hexenuronic acid.
The treatment may be continuous (e.g. in a flow-through reactor), or batch. Pulp is treated in the presence of water, in other words the pulp received from the pulp cooking (and/or other delignification) process is slurried with water so that the consistency of the slurry in the pre-treatment according to the invention is about 0.1 to 60% (solids by weight), preferably about 1-20%. The pre-treatment is preferably effected by mixing. In continuous mixing, stationary mixers may be used.
The invention may be practiced with pulps which are produced by means of a sulphate process or other alkaline methods, and contain hexenuronic acid. The term “sulphate process” means a cooking method in which the primary cooking chemicals are sodium sulfide and sodium hydroxide (kraft cooking). Other alkaline cooking processes include, for example, extended cooks based on extending conventional sulphate cooking until the kappa number of the pulp has dropped below the value of approximately 20. These methods typically include oxygen treatment. Extended cooking methods include, for example, extended batch cooking (+AQ), EMCC® available from Kamyr, Inc. of Glens Falls, N.Y., batch cooking, Super-Batch/O 2 , MCC®/O 2 available from Kamyr, Inc. of Glens Falls, N.Y., and continuous cooking/O 2 . According to experiments, hexenuronic acid forms about 0.1 to 10 mol-% (a significant amount) of the hydrolysis products of the xylanase treatment of softwood pulp received from these cooking methods. After pre-treatment according to the invention the concentration of hexenuronic acid will drop to about 0.01 to 1 mol-%.
In the specification, the term “in connection with bleaching” means that the acidic pre-treatment is effected either prior to bleaching, during bleaching or, at the latest, after bleaching. When substances reacting electrophilically, e.g. chlorine, chlorine dioxide, ozone or peracids, are used as bleaching chemicals, it is especially preferable to effect pre-treatment prior to bleaching because in this way it is possible to reduce the consumption of bleaching chemicals. It if the treatment is practiced on unbleached pulp it changes characteristics. e.g. bleachability, of the cellulose pulp. On the other hand, when using oxygen gas and/or peroxide in bleaching (or bleaching treatment), it is also possible to effect pre-treatment according to the invention after bleaching. In the latter case, the treatment is preferably carried out immediately after bleaching prior to possible drying of the pulp (i.e. to air-dried pulp). The pre-treatment may be effected between the bleaching stages of a bleaching sequence.
The following are examples of suitable bleaching sequences:
A-O-Z-P
AQ-O-Z-P
A-O-ZQ-P
A-O-Pn
AQ-O-Pn
O-A-Z-P
O-AQ-Z-P
O-A-ZQ-P
O-A-Pn
O-AQ-Pn
O-A-D-E-D
O-AD-E-D
A-O-D-E-D
O-A-X-Pn
In the above sequences the following symbols are used:
A=acidic pre-treatment at an elevated temperature according to the invention;
O=oxygen treatment;
P=peroxide treatment;
P n =several subsequent peroxide treatment stages;
E=alkali stage;
Z=ozone treatment (ZQ meaning that complexing agent is added in ozone treatment);
Q=complexing agent treatment (AQ meaning that complexing agent is added in add treatment);
D=chlorine dioxide treatment (AD meaning that there is no washing between the stages);
X=enzyme treatment; and
“-”=between stage washing.
Between bleaching stages using an oxygen chemical, there may be alkali stages. In order to make bleaching more efficient, known enzymes, such as cellulases, hemicellulases and lignases, may be employed.
The pre-treatment according to the invention is effected in a bleaching sequence either prior to an oxygen or peroxide stage, or subsequent to that, but prior to a chlorine dioxide stage, ozone stage or peracid stage (e.g. a formic acid or peracetic acid stage), in order to reduce the consumption of ozone and/or peracids. Since it is possible to improve bleachability of pulps by the pre-treatment according to the invention, the invention enables the consumption of bleaching chemicals to be significantly reduced, and/or the use of chlorine dioxide, ozone or peracids in bleaching to be eliminated.
Many chemical methods of producing chemical pulp have as the last stage an oxygen delignification stage. The pre-treatment of the invention may be effected either prior to this oxygen stage, or subsequent to it, preferably subsequent to the oxygen stage. In bleaching of hardwood pulp, the consumption of chlorine dioxide has decreased by 30-40% at a brightness level ISO 88%, the bleaching sequence being O-A-D-E-D. In bleaching softwood pulp, the corresponding reduction of consumption has been 10-20%. In both cases the yield has remained almost unchanged compared with bleaching without a stage A. Additionally, experiments have shown that stage D following stage A may be carried out without washing between the stages, in other words with the sequence O-AD-E-D.
In chlorine-free bleaching sequences comprising a bleaching stage with an electrophilic bleaching chemical, e.g. ozone or peracid, it is preferable that the acid treatment is carried out prior to the first stage Z, and preferably in such a way that the pulp is washed before moving on to stage Z, in order to guarantee efficient removal of hexenuronic acid from the pulp. The ozone consumption caused by hexenuronic acid (HexA) and thereby also the decrease in chemical consumption by practicing the method according to the invention can be calculated theoretically by taking into account that the hexenuronic acid consumes an equivalent amount of ozone (1 eq O 3 /HexA). Typically, the saving in the consumption is 1 to 3 kg O 3 per ton pulp. In the acid treatment, furan derivatives forming out of hexenuronic acid consume twice the amount of ozone, and therefore it is preferable to wash the pulp as efficiently as possible after the acid treatment, prior to the bleaching stage. [The above discussion is applicable to all other chlorine-free electrophilic bleaching chemicals, such as peracetic acid, persulphuric acid, and peroxomolybdates.]
Reducing the consumption of the bleaching chemical by acid treatment according to the invention is based on the fact that in removal of hexenuronic acid, the amount of reactive acid groups in bleaching is decreased, and thus there will also be less material to be bleached.
According to one preferable embodiment, the primary bleaching chemical used is a peroxide-containing substance (usually hydrogen peroxide). Thus, it is possible to produce pulp, the brightness reversion tendency of which, expressed as a post number pc [number], is smaller than 2. The brightness reversion tendency cannot be prevented by any other efficient way than by removing hexenuronic acid. Since in the acid treatment according to the invention detrimental heavy metal concentrations are also reduced, it is preferable to effect the acid treatment prior to the first P-stage. Peroxide treatment is most suitably accompanied by oxygen gas pre-treatment.
The pH of the pulp slurry treated with oxygen is first set to the value of about 3-4 and the temperature of the pulp is raised to about 90-130° C., and it is kept at that temperature at least 5 minutes, subsequent to which it is treated with hydrogen peroxide under alkaline conditions in order to produce bleached pulp. Instead of hydrogen peroxide, a peroxide-containing substance may be used (for example Caro's acid or a corresponding substance), which degrades in suitable conditions (e.g. alkaline conditions) to form hydrogen peroxide or peroxo-ions.
In order to remove heavy metals bound to the cellulose pulp, the pre-treatment according to the invention may be effected in the presence of chelates which bind heavy metals. EDTA and DTPA are examples of suitable chelating agents. In general, chelating agents are dosed into the pulp in the proportion of about 0.2% of the pulp by weight. However, an advantage of the acidic pre-treatment according to the invention is that metals can be removed rather efficiently even without chelating agent treatment, as disclosed in Example 10.
Acidic pre-treatment may also be practiced to unbleached or bleached pulp to modify characteristics relating to the qualities of paper. Thus, by removing acid groups water retention capacity of the pulp can be decreased, whereby it is possible to produce stiffer pulp applicable for use in packing boards, for example.
According to one aspect of the present invention a method of treating chemical cellulose pulp produced by alkaline delignification and having a kappa number of under 24, having hexenuronic acid therein, comprises the steps of: (a) Treating chemical cellulose pulp produced by alkaline delignification having a kappa number under 24 by removing at least 50% of the hexenuronic acid from the pulp. And, (b) bleaching the chemical cellulose pulp produced by alkaline delignification having a kappa number under 24 in at least one bleaching stage. Step (a) is typically practiced by treating the pulp at a temperature over 85° C. and at a pH between about 2-5 for sufficient time to remove at least 50% of the hexenuronic acid and to reduce the kappa number by at least 2 units. Typically step (a) is practiced for at least a time t, where t=0.5 exp(10517/(T+273)−24), in minutes, and where T is the treatment temperature in degrees C.
While step (a) may be practiced prior to, substantially simultaneously with, or after step (b), where step (b) is practiced by bleaching the pulp electrophilically (using chlorine, chlorine dioxide, ozone, peracid, etc.) step (a) is practiced before step (b). During the practice of step (a) the pulp has a consistency of between 0.1-50%, preferably about 1-20%. Step (a) is most desirably practiced at a temperature of between about 90-110° C. and a pH of between about 2.5-4 and for between five minutes to ten hours, most desirably between 10-240 minutes. The pulp treated in step (a) may be hardwood pulp having a kappa number of about 14 or less, or softwood pulp with such a kappa number. Where step (b) is practiced by bleaching the pulp in an ozone stage it is typically followed by at least one additional bleaching stage. Step (a) is practiced to reduce the kappa number about 3-6 units under most circumstances, and desirably to remove at least 80% of the hexenuronic acid (e.g. about 90-97%), and to produce pulp with a pc-number small than 2 (even if step (b) is peroxide bleaching).
According to another aspect of the present invention, a method of producing chemical cellulose pulp is provided comprising the following steps: (a) Effecting alkaline delignification of comminuted cellulosic fibrous material to produce chemical cellulose pulp having a kappa number of under 24, and having hexenuronic acid therein (e.g. at a concentration of about 0.1-10 mol-% of the hydrolysis products with x y lanase thereof). (b) Treating the chemical cellulose pulp from step (a) at a temperature of between 85-180° C. and at a pH between about 2-5 for at least a time t, where t=0.5 exp(10517/(T+273)−24), in minutes, and where T is the treatment temperature in degrees C., to remove at least 50% of the hexenuronic acid from the pulp (e.g. to reduce the concentration thereof to about 0.01-1 mol-% of the hydrolysis products with x y lanase). And, (c) Bleaching the chemical cellulose pulp from step (a) in at least one bleaching stage prior to, simultaneously with, or after step (b). Step (b) is typically practiced at atmospheric pressure for a time between 10-360 minutes, or when at superatmospheric pressure over 100° C. for a time between 5-100 minutes; and to remove about 90-97% of the hexenuronic acid.
The invention also contemplates cellulose chemical pulp produced by the steps of: (a) Effecting alkaline delignification of comminuted cellulosic fibrous material to produce chemical cellulose pulp having a kappa number of under 24, and having hexenuronic acid therein. (b) Treating the chemical cellulose pulp from step (a) at a solids consistency between 0.1-50% at a temperature of between 86-180° C. and at a pH between 2.0-6.0 for at least a time t, where t=0.5 exp(10517/(T+273)−24), in minutes, and where T is the treatment temperature in degrees C., to remove at least 50% of the hexenuronic acid from the pulp. And (c) bleaching the chemical cellulose pulp from step (a) in at least one bleaching stage prior to, simultaneously with, or after step (b), so that the pulp has a brightness of at least about 80 ISO (preferably at least 90 ISO). Even where step (e) is peroxide bleaching, the pulp produced still has a pc number less than 2.
It is a primary object of the present invention to significantly enhance the bleachability of chemical cellulose pulp produced by alkaline delignification. This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graphical representation illustrating the effect of acidity on hydrolysis velocities of arabinose amd hexenuronic acid of pine sulfate pulp at a temperature of about 80° C.; and
FIG. 2 is a graphical representation of reaction time plotted against temperature for different levels of hexenuronic acid removal.
DETAILED DESCRIPTION
FIG. 1 graphically illustrates the effect of acidity on the hydrolysis velocities of arabinose acid groups and hexenuronic acid of pine sulphate pulp at a temperature of about 80° C. Theoretical curves have been fitted to experimental points in accordance with the equations illustrated in Example 2 respectively.
FIG. 2 illustrates the dependency of the time necessary for removal of hexenuronic acid on the temperature at a scale of 80 to 140° C., birch sulphate pulp having been treated with acid at pH 3.5, according to the invention. At this pH the reaction velocity is nearly maximal. At higher pH values the retention time should be longer at a certain temperature. The three upper curves illustrate the optimal operating range, wherein 95%, 90% and 80%, respectively, of the hexenuronic acid has been removed. The broken line illustrates the lowest limit of the retention time, where 60% of the hexenuronic acid has been removed.
In the examples below the kappa numbers of the pulps have been defined according to standard SCAN-C 1:77, the viscosity according to standard SCAN-CM 15:88, and the brightness according to standard SCAN-C 11:75. The brightness reversion tendency is measured by means of a dry heating method (24 h, 105° C.). The PC number was counted from the results.
EXAMPLE 1
4-O-methylglucuronoxylan isolated from hardwood was treated in 1 M sodium hydroxide liquor at a temperature of 160° C. for 2 hours. The liquor was cooled and the xylan precipitated from the liquor by adjusting the liquor neutral. The precipitated xylan was washed and dried, subsequent to which it was treated with endoxylanase. The hydrolysate was fractionated by using anion exchange chromatography and gel filtration. In this way, the oligosaccharide fraction was isolated, which fraction was by means of NMR spectroscopy discovered to contain 4-deoxy-p-L-threo-hex4-enuronoxylotriose (80%) and -tetraose (20%).
Part of the oligosaccharide liquor was dissolved into 10 mM acetate buffer (pH 3.7) in deuterium oxide. The liquor was inserted into an NMR tube and changes therein were followed by means of 1H NMR spectroscopy at a temperature of 80° C. for 17 hours.
The degradation of hexenuronic acid groups was in accordance with the first order. The conversion was 55% 17 hours after the reaction time. Hydrolysis of xylosidic linkages was not to be discovered. When hexenuronic acid degraded, an almost equivalent amount of compounds was generated, which compounds were identified as furan-2-carboxylic acid (δ H3 =7.08 ppm), J H3′H4 =3.5 hz, J H4,H5 =1.7 Hz, J H5 =0.8 Hz), and formic acid (δ H =8.37 ppm). In addition, a small amount of component identified as 2-furaldehyde-5-carboxylic acid (δ H3 =7.13 ppm, δ H4 =7.52 ppm, δ CHO =9.60 ppm, J H3,H4 =3.5 Hz) was generated.
According to the example, the hexenurosidic linkages may be selectively hydrolyzed under mild conditions without significant hydrolysis of xylosidic linkages. Correspondingly, it can be concluded that glucosidic and mannosidic linkages of cellulose and glucomannan, being stronger than xylosidic linkages of xylan, are stable in these conditions.
EXAMPLE 2
Pine sulphate pulp (kappa number 25.9) was incubated in buffered liquors (pH 1.5-7.8) at different temperatures (25, 50 and 80° C.) for 2 hours. Subsequent to the treatments, the pulp samples were washed with water. The washed pulps were treated with xylanase, and the hydrolysates were analyzed by means of 1 H NMR spectroscopy.
Changes in the carbohydrate composition of the pulp were found only at the highest temperature used (80° C.). Deviating from hydrolysis of ordinary glycosides, hydrolysis of hexenuronic acid groups was not directly proportional to the hydronium ion concentration (Equation 1), but the pH dependancy of the reaction velocity clearly showed that the reaction occured through a free hexenuronic acid group without catalysis caused by a bydronium ion (Equation 2, FIG. 1 ).
k=k O [H 3 O + ] (1)
k=k O {1/(1+K a /[H 3 O + ]} (2)
According to the example, hexenuronic acid groups of the cellulose pulp may be selectively removed under slightly acidic conditions (pH>2) at a raised temperature. Partial hydrolysis of arabinose groups occurs, but the loss in yield caused by this is diminutive due to the low concentration of arabinose in cellulose pulps (softwood pulps 1%, hardwood pulps 0%).
EXAMPLE 3
The oligosaccharide liquor (15.5 mg, 0.025 mmol) was added into boiling 0,01 M formiate buffer (pH 3.3, 27 ml). The liquor was refluxed for 3 hours. Samples (0.5 ml) were taken at suitable intervals and diluted with water (5 ml). The absorption of light was measured at a wavelength scale of 200-500 nm. Forming of furan-2-carboxylic acid (λmax=250 nm) was in accordance with the first order (k=0,44 h −1 ).
The molar absorptivity calculated per amount of the hexenuronic acid groups was 8,700. This absorptivity value may be used to define the hexenuronic acid concentration of cellulose pulps.
EXAMPLE 4
The oligosaccharide mixture (2.0 mg, 3.22 μmol) was dissolved into water (4.8 ml). 0.6 ml 2 M sulphuric acid and 0.6 ml 0.02 M potassium permanganate (12.0 μmol) was added into the liquor. In ten minutes, 0.12 ml 1 M potassium iodide and 100 ml water was added into the liquor. The iodine concentration of the liquor was defined spectrophotometrically (350 nm, ε=16,660). The consumption of permanganate was calculated on the basis of Equation 3.
2MnO 4 −+10I−+16H+−→2Mn 2+ +5I 2 +8H 2 O (3)
The consumption of permanganate was 7.98 μmol, i.e. 2.5 calculated per equivalent hexenuronic acid group. Since the definition of kappa number used for representing lignin concentration of cellulose pulps is done under exactly the same reaction conditions, hexenuronic acid groups may cause a considerable error in respect to the real lignin concentration.
EXAMPLE 5
Birch sulphate pulp (3 g, kappa number 16.5) was treated in 0.06 M formiate buffer (pH 3.2, 250 ml) at a temperature of 100° C. for 4 hours. Degradation of hexenuronic acid groups was followed by means of absorption of light (250 nm, ε=8,700) caused by 2-furan-carboxylic acid. The total amount of bexenuronic acid groups was calculated to be 70 meq/kg of pulp. The kappa number of the treated pulp was 10.6.
According to the invention, a considerable amount of hexenuronic acid groups can be removed from sulphate pulp, with resulting significant drop in kappa number (used for representing the delignification grade). A similar reduction can be expected to occur in the consumption of electrophilic bleaching chemicals reacting with hexenuronic acid.
EXAMPLE 6
Pine sulphate pulp bleached with oxygen and peroxide (9 g, kappa number 5.3) was treated in 0.06 M formiate buffer (pH 3.2, 600 ml) at a temperature of 100° C. for 2.5 hours. Degradation of hexenuronic acid groups was followed by means of absorption of light (250 nm, ε=8,700) caused by 2- furan-carboxylic acid.
The total amount of hexenuronic acid groups was calculated to be 48 meq/kg of pulp. All hexenuronic acid groups were removed from the pulp in the reaction time of about 30 minutes. The treated pulp was filtered in a Bichner funnel, and washed with water. Compared with the original pulp, the treated pulp was infiltrated very easily. The kappa number of the treated pulp was 2.3.
The kappa number of sulphate pulp bleached with oxygen and peroxide according to the invention is very low after treatment removing hexenuronic acid groups. The treatment according to the invention significantly improves possibilities to produce full-bleached TCF pulps without ozone bleaching.
EXAMPLE 7
Birch sulphate pulp (100 g, kappa nurabar 11.6) bleached with oxygen was mixed in water (3 1). The pH of the suspension was adjusted to the value 3,4 by adding 2 ml strong formic acid. The suspension produced in this way was incubated at a temperature, of 100° C. for 4 hours. Degradation of hexenuronic acid groups was followed by means of UW absorption (250 nm, ε=8,700) caused by 2-furan carboxylic acid. The amount of the removed hexenuronic acid was calculated to be 54 meq/kg of pulp, which is approximately 98% of the total amount of hexenuronic acid groups of the pulp. The kappa number of the treated pulp was 6.2.
Chelating With EDTA (0.2% of the pulp) was carried out to both treated and non-treated pulp at a concentration of 3.5%. The treatment was practiced at a temperature of 60° C., the duration thereof being 45 minutes.
After washing, peroxide bleaching (3% of the pulp being hydrogen peroxide) was effected to the pulps at a concentration of 10%. Magnesium sulphate (0.5% of the pulp) was used as stabilizer, and sodium hydroxide (1.8% of the pulp) as alkali, the temperature being 90° C. and the bleaching time 180 minutes. The kappa number, viscosity, brightness and brightness reversion tendency (pc number) were defined of the washed pulps. The characteristics of the pulps are shown in Table 1.
Table 1. The effect of the pre-treatment (A) on bleachability with peroxide (P) of birch sulphate pulp bleached with oxygen (0).
TABLE 1
The effect of the pre-treatment (A) on bleachability with
peroxide (P) of birch sulphate pulp bleached with oxygen (O).
Residue
H 2 O 2
Kappa
Viscosity
Brightness
Stage
(% of pulp)
no.
(ml/g)
(% ISO)
pc no.
O
11.5
1165
49.7
OP
0
9.3
1125
61.0
2.5
OA
6.2
1065
49.9
OAP
2.1
3.2
980
76.1
1.1
The results show that the pre-treatment strongly affected the action of the pulp in the peroxide stage. The consumption of peroxide was crucially reduced, but in spite of that, the rise in brightness was more than twice as great compared to the non-treated pulp. The brightness reversion tendency of the pre-treated pulp was, expressed as a pc number, over 50% lower than the brightness reversion tendency of the non-treated pulp.
EXAMPLE 8
Unbleached birch sulphate pulp (kappa number 15.4) was treated with formic acid at a concentration of 5% so that the pH of the slush was 3.0, 3.5 or 4.0. The pulps treated in this way were incubated in 150 ml-pressure vessels at temperatures of 85, 95, 105 and 115° C. for 0.2-24 hours. Disengagement of hexenuronic acid groups was followed by defining the concentrations of furan derivatives having formed out of hexenuronic acid groups in the filtrate. The kappa number and viscosity were defined of the incubated pulps.
The decrease in the kappa number was in a linear way dependent on the decrease in the hexenuronic acid concentration. The maximal reduction of hexenuronic acid concentration was 50 meq/kg, corresponding to a 6.3-unit reduction of the kappa number. 90% of the hexenuronic acid being removed, the yield of the treatment was 98% calculated on the basis of TOC. The degradation of hexenuronic acid groups was in accordance with the first-order reaction kinetics. The minimum retention time (reduction of 60% in the hexenuronic acid concentration) required by the treatment, and the optimal retention time (reduction of 80-95% in the hexenuronic acid concentration) are illustrated by means of curves fitted to experimental points (FIG. 2 ). At pH 3.0-3.6 the degradation velocity of hexenuronic acid was very close to its maximum value. At higher pH values the retention times required are longer due to a slower reaction velocity.
EXAMPLE 9
Birch sulphate pulp kappa number 10.3) bleached with oxygen was treated under conditions according to Example 8 to remove hexenuronic acid groups. The kappa number after the treatment was 5.4. Both acid-treated and non-treated pulp was bleached with DED sequence using several doses of chlorine dioxide and alkali. Being bleached to the brightness level 88.0% ISO, the acid-treated pulp consumed 2.6% chlorine dioxide calculated as active chlorine, and 1.4 % sodium hydroxide. The corresponding consumption percentages chlorine dioxide and sodium hydroxide by the non-treated pulp were 4.3 and 0.8, respectively. The yield of the DED sequence was 97.1% for the acid-treated pulp and 95.5% for the non-treated pulp. Thus, removal of hexenuronic acid caused the consumption of chemicals of the ECF bleaching to decrease by 42-43% without lowering the yield of the bleaching. The tensile index and tear index of the sheets made of the pulps were identical at the same density of the sheet.
EXAMPLE 10
Pine sulphate pulp (100 g, kappa number 25.9) was mixed in water (31). The pH of the suspension was adjusted to the value 3.5 by adding 1.6 ml strong formic acid. The suspension produced in this way was incubated at a temperature of 100° C. for 2.5 hours. Degradation of hexenuronic acid groups was followed by means of UV absorption (250 nm, ε−8,700) caused by 2-furan-carboxyl acid. The total amount of the removed hexenuronic acid was calculated to be 32 meq/kg of pulp, which corresponds to about 95% of all hexenuronic acid of the pulp. Chelating with EDTA (0.2% of the pulp) was carried out to both non-treated and treated pulp at a concentration of 3%. The treatment was effected at a temperature of 50° C., the duration thereof being 45 minutes, The metal concentrations of the pulps were defined with an atomic absorption spectrophotometer.
The treatment removing hexenuronic add especially decreased the iron and manganese concentrations of the pulp (Table 2). The decrease in iron in this case significantly greater than when using chelate treatment, and even the decrease in manganese was as great as when using chelate treatment.
Table 2. The effect of the pre-treatment (A) and chelating (0) on metal concentrations of pine sulphate pulp (mg/kg)
TABLE 2
The effect of the pre-treatment (A) and chelating (O) on
metal concentrations of pine sulphate pulp (mg/kg)
Treatment
Iron
Copper
Manganese
—
22.0
6.5
36.8
A
10-7
5.7
2.4
Q
20.9
0.9
1.8
AQ
10.4
1.3
0.2
Since iron and manganese are the most detrimental metals as—regards to TCF bleaching, the use of chelating agents may be replaced either partly or totally with treatment removing hexenuronic acid. If chelating agents are used, it is preferable to add them in connection with the treatment removing hexenuronic acid.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended modifications and equivalent arrangements included within the spirit and scope of the appended claims. | Chemical cellulose pulp produced by alkaline delignification and having a kappa number of under 24 (e.g. 14 or below) having hexenuronic acid is treated to remove at least 50% of the hexenuronic acid (e.g. 90-97%) such as by treating the pulp at a temperature over 85° C. (e.g. about 90-180° C., preferably about 90-110° C.) at a pH between about 2-5 (e.g. about 2.5-4), which also results in a reduction of kappa number by at least two units (e.g. about 2-9 units, preferably about 3-6 units). The treatment time t, in minutes, is at least 0.5 exp(10517/(T+273)−24), where T is the treatment temperature in degrees C. The chemical cellulose pulp is bleached in at least one bleaching stage; where the bleaching stage is a chlorine dioxide, ozone, or peracid, treatment takes place before bleaching. Under some other circumstances treatment can take place simultaneous with bleaching or after bleaching. | 3 |
RELATED ART
1. Field of the Invention
The present disclosure is directed to bone plates and, more specifically, to bone plates having fastener holes that may be utilized as locking holes or as compression holes, depending upon the initial placement of the fastener with respect to the fastener hole.
2. Brief Discussion of Related Art
Bone plates used in conjunction with screws to fix bone fractures often contain locking screw holes and compression slots. Locking screw holes provide additional plate-to-screw fixation to lock bone fragments in place and aid in healing of bone fractures. Compression slots, on the other hand, are used to compress the ends of bone fragments together to aid in primary healing.
Typically, a bone plate includes at least one locking screw hole and at least one compression slot. The location of the holes and slots dictate the locations on the bone plate where the surgeon can apply locking or compression forces.
INTRODUCTION TO THE INVENTION
The present invention is directed to bone plates having fastener holes that may be utilized as locking holes or as compression holes, depending upon the initial placement of the fastener with respect to the fastener hole. By providing a single hole that can act as a compression hole or a locking hole, the bone plate provides a surgeon with greater flexibility as to the placement of locking fasteners and compression fasteners in a smaller footprint than in a traditional plate having dedicated space for each type of hole.
It is a first aspect of the present invention to provide a bone plate including a hybrid through screw hole, where the hybrid through screw hole includes a top opening and a bottom opening, the top opening being generally circular and including a widthwise dimension and a lengthwise dimension normal to the widthwise dimension, where an interior wall of the bone plate extends between the top opening and the bottom opening, where at least a portion of the interior wall proximate the top opening is threaded, and where at least one of the widthwise dimension and the lengthwise dimension is decreased between the top opening to the bottom opening, while the other of the widthwise dimension and the lengthwise dimension does not substantially decrease between the top opening and the bottom opening.
In a more detailed embodiment of the first aspect, the interior wall includes a first portion having a first circumferential curvature and a second portion having a second circumferential curvature, wherein the first circumferential curvature is larger than the second circumferential curvature. In yet another more detailed embodiment, the second portion does not include threads. In a further detailed embodiment, the first portion is at least one of arcuate and tapered in the vertical direction and, the second portion includes a vertical wall. In still a further detailed embodiment, the interior wall includes a first portion having a first circumferential curvature, a second portion having a second circumferential curvature, and a third portion having a third circumferential curvature, wherein the first circumferential curvature is larger than the second circumferential curvature and the third circumferential curvature. In a more detailed embodiment, the second portion is opposite the third portion. In a more detailed embodiment, the second circumferential curvature is generally the same as the third circumferential curvature. In another more detailed embodiment, the first portion includes threads, the second portion does not include threads and, the third portion does not include threads. In yet another more detailed embodiment, the first portion is at least one of arcuate and tapered in the vertical direction, the second portion includes a vertical, wall and, the third portion includes a vertical wall.
It is a second aspect of the present invention to provide a bone plate comprising a combination compression and locking through hole, where the combination hole includes a first portion having a circular, horizontal cross-section and a second portion having an oblong, horizontal cross-section, where the circular, horizontal cross-section and the oblong, horizontal cross-section lie along differing planes perpendicular to a central axis extending through the combination compression and locking through hole.
In a more detailed embodiment of the second aspect, the bone plate further includes a plurality of combination compression and locking through holes, where each of the plurality of combination compression and locking through holes includes a first portion including a circular, horizontal cross-section and a second portion including an oblong, horizontal cross-section. In yet another more detailed embodiment, the combination compression and locking through hole is at least partially threaded. In a further detailed embodiment, the first portion is threaded and the second portion is unthreaded. In still a further detailed embodiment, the first portion includes a diameter D, the second portion includes a maximum length L and, the diameter D is approximately equal to the length L.
It is a third aspect of the present invention to provide a bone plate comprising a through screw hole demarcated by an interior surface of the bone plate that extends between a top opening and a bottom opening, the top opening having a continuous arcuate shape and allowing throughput of a first imaginary cylinder having a circular cross-section with a diameter D 1 , the interior surface having a first segment that is at least partially threaded and tapers to a stopping distance SD to inhibit throughput of the first imaginary cylinder at a location between the top opening and the bottom opening, the interior surface having a second segment adjacent to the first segment, the first segment and the second segment allowing throughput of a second imaginary cylinder having a circular cross-section with a diameter D 2 , where the diameter D 1 is greater than the diameter D 2 , where the stopping distance SD is greater than D 2 , and wherein a maximum horizontal distance across the second segment is greater than 1.3 times D 2 .
In a more detailed embodiment of the third aspect, the interior surface of the first segment includes a first circumferential curvature and the second segment includes a second circumferential curvature, wherein the first circumferential curvature is larger than the second circumferential curvature. In yet another more detailed embodiment, the second segment does not include threads. In a further detailed embodiment, the first segment is at least one of arcuate and tapered in the vertical direction and, the second segment includes a vertical wall. In still a further detailed embodiment, the interior surface includes a first segment having a first circumferential curvature, the second segment includes a second portion having a second circumferential curvature and a third portion having a third circumferential curvature, wherein the first circumferential curvature is larger than the second circumferential curvature and the third circumferential curvature. In a more detailed embodiment, the second portion lies generally opposite the third portion. In a more detailed embodiment, the second circumferential curvature is generally the same as the third circumferential curvature. In another more detailed embodiment, the first portion includes threads, the second portion does not include threads and, the third portion does not include threads. In yet another more detailed embodiment, the first portion is at least one of arcuate and tapered in the vertical direction, the second portion includes a vertical wall and, the third portion includes a vertical wall.
It is a fourth aspect of the present invention to provide a method of forming a bone plate comprising: (a) fabricating a bone plate to include a first through hole, where at least one of a width and a length of the hole changes along a depth of the hole; (b) plunge milling an interior surface of the bone plate demarcating the first through hole to remove at least a portion of the bone plate to increase at least one of the width and the length of the through hole; and (c) threading at least a portion of the first through hole.
In a more detailed embodiment of the fourth aspect, threading at least a portion of the first through hole occurs before the plunge milling act. In yet another more detailed embodiment, threading at least a portion of the first through hole occurs after the plunge milling act. In a further detailed embodiment, the length and width of the through hole at a top surface of the bone plate are identical. In still a further detailed embodiment, the length and width of the through hole at a bottom surface of the bone plate are identical after the fabricating act and, the length and width of the through hole at the bottom surface of the bone plate are not identical after the plunge milling act. In a more detailed embodiment, the plunge milling act includes using an end mill to remove material in a cylindrical swath, a first axis extends through a center of the through hole, a second axis extends through a circular center of the cylindrical swath and, the first axis is parallel with the second axis. In a more detailed embodiment, the plunge milling act includes using an end mill to remove material in a cylindrical swath, the plunge milling act includes applying the cylindrical swath to opposing ends of the through hole to create a first cylindrical swath and a second cylindrical swath, the first cylindrical swath includes a first axis extending through a circular center thereof, the second cylindrical swath includes a second axis extending through a circular center thereof, the first axis is parallel with the second axis and, the first axis is offset from the second axis.
It is a fifth aspect of the present invention to provide a method of forming a bone plate comprising fabricating a bone plate to include a combination compression and locking hole, where the combination compression and locking hole includes a first portion having a circular cross-section and a second portion having an oblong cross-section, where the circular cross-section and the oblong cross-section lie along differing planes perpendicular to a central axis extending through the combination compression and locking hole.
In yet another more detailed embodiment of the fifth aspect, the fabricating step includes machining a bone plate from a solid block of material. In still another more detailed embodiment, a first portion of the hole tapers to reduce a cross-sectional area of the hole. In a further detailed embodiment, the fabricating step includes forming threads within an interior surface of the bone plate demarcating the hole. In still a further detailed embodiment, the fabricating step includes removing some of the bone plate to increase at least one of a width and a length of the hole after the hole has been formed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevated perspective view of an exemplary bone plate incorporating at least one combination locking and compression screw hole.
FIG. 2 is an overhead view of the exemplary combination locking and compression screw hole shown in FIG. 1 .
FIG. 3 is a cross-sectional view taken along line C in FIG. 2 .
FIG. 4 is a cross-sectional view takes along line B in FIG. 2 .
FIG. 5 is an overhead view of a locking screw hole while a portion is bored out using an end mill.
FIG. 6 is an overhead view of the locking screw hole of FIG. 5 , with an opposing portion being bored out using an end mill to form the combination locking and compression screw hole.
FIG. 7 is an elevated perspective view of an exemplary locking screw.
FIG. 8 is a vertical cross-section of the exemplary locking screw of FIG. 7 taken at the middle.
FIG. 9 is an elevated perspective view of an exemplary compression screw.
FIG. 10 is a vertical cross-section of the exemplary compression screw of FIG. 9 taken at the middle.
FIG. 11 is a vertical cross-section of the exemplary bone plate of FIG. 1 in position with respect to a bone, where a compression screw is partially inserted into the combination locking and compression screw hole.
FIG. 12 is a vertical cross-section of the exemplary bone plate of FIG. 1 in position with respect to a bone, where a compression screw is fully inserted into the combination locking and compression screw hole in order to shift the position of the plate and compress the bone.
FIG. 13 is a vertical cross-section of the exemplary bone plate of FIG. 1 in position with respect to a bone, where a locking screw is partially inserted into the combination locking and compression screw hole.
FIG. 14 is a vertical cross-section of the exemplary bone plate of FIG. 1 in position with respect to a bone, where a locking screw is fully inserted into the combination locking and compression screw hole in order to lock the angular position of the screw with respect to the plate and bone.
DETAILED DESCRIPTION
The exemplary embodiments of the present disclosure are described and illustrated below to encompass bone plates and, more specifically, to bone plates having fastener holes that may be utilized as locking holes or as compression holes, depending upon the initial placement of the fastener with respect to the fastener hole. Of course, it will be apparent to those of ordinary skill in the art that the preferred embodiments discussed below are exemplary in nature and may be reconfigured without departing from the scope and spirit of the present invention. However, for clarity and precision, the exemplary embodiments as discussed below may include optional steps, methods, and features that one of ordinary skill should recognize as not being a requisite to fall within the scope of the present invention.
Referencing FIG. 1 , an exemplary bone plate 100 comprises a clavicle bone plate. This clavicle bone plate 100 includes an elongated, longitudinal dimension that includes a series of fastener holes 102 , 103 , 102 A distributed in a spaced-apart fashion along the longitudinal length. Each fastener hole 102 , 103 , 102 A extends between the top surface 104 and bottom surface 106 . In this exemplary embodiment, the top surface 104 is generally convex from superior to inferior, while the bottom surface 106 is generally concave from superior to inferior. This shape is operative to form a channel defined by the bottom surface 106 that is adapted to receive a biologic substrate, such as bone. And each fastener hole 102 , 103 , 102 A is generally centered between a superior side 108 and an inferior side 110 .
In this exemplary embodiment, the fastener holes 102 , 103 , 102 A generally take on three forms. A first form hole 102 includes a generally circular through opening that extends between the top and bottom surfaces 104 , 106 . This first form hole 102 has a horizontal circular cross-section that changes in diameter in order to provide a taper in the hole, with the taper being located proximate the bottom surface. It should be noted, however, that wherever a horizontal cross-section of this first hole 102 is taken, the cross-section will be circular. In order to form this hole, a milling machine (not shown) uses an end mill to remove material from the bone plate in order to form the interior wall that defines the through hole. As part of this first form hole 102 , the milling machine removes material from the hole to create a taper from top to bottom so that the area of the horizontal, circular cross-sections at some point between the top and bottom decreases. After the milling machine has formed the hole, the wall of the hole is relatively smooth. Thereafter, a threading procedure is carried out to form threads on the interior of the hole 102 . These threads, however, do not generally change the circular cross-section of the hole. But the second form hole 103 does not include a horizontal circular cross-section.
In contrast to the first hole 102 , the second form hole 103 includes an elongated shape having a non-circular cross-section. By way of example, the second form hole 103 includes a longitudinal dimension that is greater than a widthwise dimension (superior to inferior). At the top of the second form hole 103 , proximate the top surface 104 , the longitudinal dimension accommodates multiple longitudinal positions for a screw (such as a locking screw 180 or a compression screw 210 ). But the widthwise dimension is generally uniform and allows for positioning of the screw in only a single widthwise position. In other words, the second form hole 103 allows for positioning the screw in a number of longitudinal positions, but the position of the screw in the superior-to-inferior (i.e., widthwise) direction is generally not amendable to multiple positions. Similarly, the first form hole 102 does not allow for multiple positions of the screw in the inferior-to-superior direction. But, conversely to the second form hole 103 , the first form hole 102 fails to allow multiple positions of the screw in the longitudinal direction.
The two screw form holes 102 , 103 also differ in that the first form hole 102 is threaded, while the second form hole 103 is not threaded. In order to retain the screw within the second form hole 103 , a circumferential flange 140 (recessed in between the top and bottom surfaces 104 , 106 ) extends into the hole and is operative to decrease the through hole diameter enough so that throughput of the screw head is retarded. Because of the longitudinal position variance provided by the second form hole 103 , compression screws 210 are more commonly inserted into this hole, as opposed to locking screws 180 . As would be expected, the threaded nature of the first form hole 102 results in locking screws 180 being inserted into these holes more commonly than compression screws 210 .
A third form hole 102 A comprises a hybrid hole that may be utilized as a locking screw hole or as a compression screw hole. In exemplary form, the hybrid fastener hole 102 A includes a circular cross-section at the top surface 104 and an oblong cross-section at the bottom surface 106 . More specifically, the oblong cross-section of the hole 102 A at the bottom surface 106 includes a first, larger dimension 112 running longitudinally along the longitudinal dimension of the hole 102 A, and a second, smaller dimension 114 running inferiorly between the superior and inferior sides 108 , 110 . It should be noted that the larger dimension 112 is approximately the same as the diameter of the hole 102 A at the top surface 104 . In this exemplary embodiment, the larger dimension 112 is 0.205 inches, while the smaller dimension is 0.145 inches. Those skilled in the art will understand that differing dimensions (greater or lesser) are well within the scope of the invention.
Located between the top and bottom surfaces 104 , 106 for the first and third form holes 102 , 102 A are helical threads 120 that extend from portions of an interior wall 122 to delineate the vertical cross-section of each hole 102 A. The interior wall 122 takes on a general shape that resembles a bowl or a frustum, where portions of the interior wall 122 departing from the bowl or frustum shape may not include the helical threads 120 .
An exterior of the bone plate 100 includes a number of indentations 130 that are formed into the superior and inferior sides 108 , 110 . Each indentation 130 is located opposite another indentation so that a pair of indentations generally interposes consecutive fastener holes 102 , 102 A. In this exemplary embodiment, each indentation 130 operates to decrease the widthwise dimension (superior 108 to inferior 110 ) of the bone plate 100 , while at the same time cooperating with arcuate depressions 132 to decrease the thickness (top surface 104 to bottom surface 106 ) of the bone plate. Specifically, the arcuate depressions 132 extend along the top surface 104 and terminate just shy of the superior-inferior midline extending longitudinally along the length of the bone plate 100 .
To fabricate the exemplary bone plate 100 , a solid block of metal (e.g., stainless steel, titanium, etc.) is milled to form the general shape of the bone plate. This includes milling the bone plate 100 to have the requisite length, width, and thickness, in addition to providing a top surface 104 that is convex and a bottom surface 106 that is concave along the longitudinal length. In addition, the milling is operative to form the indentations 130 and remove material from the bone plate 100 in order to form the depressions 132 . After the general shape of the bone plate is finished, the fastener holes of the first and second form 102 , 103 are formed through the bone plate 100 .
Referring to FIGS. 5 and 6 , in order to form the hybrid holes 102 A, an additional step is taken to modify one or more of the first form holes 102 . Specifically, a milling machine is utilized to carry out a plunge down operation on the first form hole 102 that removes a portion of the internal threads and interior wall in the longitudinal direction to create an oblong opening at the bottom of the hole. As discussed previously, the first form hole 102 has a diameter of 0.205 inches (and a circumferential curvature that matches this 0.205 inch diameter) at the top surface 104 and a diameter of 0.145 inches at the bottom surface 106 prior to the plunge down operation. After the plunge down operation is complete, the diameter of 0.205 inches at the top surface 104 remains unchanged, while the longitudinal dimension of the hole at the bottom surface 106 is changed to create an oblong shape. Specifically, the plunge down operation creates an oblong hole at the bottom surface 106 having a longitudinal dimension of 0.205 inches, while maintaining the widthwise dimension of 0.145 inches.
The plunge down operation involves using an end mill 150 having an outside diameter of 0.138 inches, where the end mill is oriented in parallel to the through axial center of the hole and is longitudinally offset 0.03 inches from this axial center, but is centered in the superior-to-inferior direction. In a first plunge down operation (see FIG. 5 ), the end mill 150 is longitudinally offset 0.03 inches in the proximal direction and removes a portion of the interior surface to create a wall having a circumferential curvature of a circle having a diameter of 0.138 inches. In a second plunge down operation, the end mill 150 is longitudinally offset 0.03 inches in the distal direction (see FIG. 6 ) and removes another portion of the interior surface to create another wall having a circumferential curvature of a circle having a diameter of 0.138 inches. The result of the plunge down operation is a hole 102 A having hybrid characteristics to accept either a locking or compression screw 180 , 210 without sacrificing the functionality of a locking screw or the functionality of a compression screw.
Referring to FIGS. 7 and 8 , an exemplary locking screw 180 includes a head 182 and a shaft 184 extending from the head. The head 182 comprises a dome 186 that transitions into an arcuate circumferential surface 188 that includes helical threads 190 adapted to engage the threads 120 of the bone plate holes 102 , 102 A. The circumferential surface 188 transitions into an underneath planar surface 192 at the bottom of the head 182 to take on a frustum profile. Opposite the bottom of the head 182 is an opening 194 formed at the apex of the dome 186 . The opening 194 extends through the head 182 and into a head end 196 of the shaft 184 . In exemplary form, the opening 194 is defined by a series of six alternating semicircular walls 198 and six straight walls 200 that form a hexagonal pattern. At the base of the walls 198 , 200 is a conical wall 202 that defines a conical part of the opening 194 terminating in the head end 196 of the shaft 184 . An exterior surface 204 of the shaft 184 includes helical threads 206 that are adapted to engage a biologic substrate (not shown), such as bone. The threads 206 extend along the shaft until reaching a pointed projection 208 at a far end of the screw 180 .
Referencing FIGS. 9 and 10 , an exemplary compression screw 210 includes a head 212 and a shaft 214 extending from the head. The head 212 includes a dome 215 that transitions into a rounded or tapered circumferential surface 216 that operates to decrease the cross-section of the head from proximal to distal, where the distal aspect transitions into the shaft. Extending through the dome 215 is an opening 218 that extends through the head 212 and into a head end 220 of the shaft 214 . In exemplary form, the opening 218 is defined by a series of six alternating semicircular walls 220 and six straight walls 222 that form a hexagonal pattern. At the base of the walls 220 , 222 is a conical wall 224 that defines a conical part of the opening 218 terminating in the head end 220 of the shaft 214 . An exterior surface 226 of the shaft 214 includes helical threads 228 that are adapted to engage a biologic substrate (not shown), such as bone. The threads 228 extend along the shaft 214 until reaching a tapered projection 230 at a far end of the screw 210 .
Referring to FIGS. 11 and 12 , the hybrid holes 102 A of the exemplary bone plate 100 may be utilized to receive a compression screw 210 in order to exert a compressive force on the bone 240 . In exemplary form, a bone or bone fragments 240 is mounted to the bone plate 100 using a combination of compression and locking screws 210 , 180 . Presuming a surgeon finds it desirable to provide compression using the hybrid hole 102 A, a pilot hole may be drilled to receive a compression screw 210 . By way of example, the pilot hole is offset distally with respect the axial center of the hole 102 A, which allows for the compression screw 210 to be axially offset from the center of the hole (see FIG. 11 ). When the compression screw 210 is initially inserted, the smaller diameter threaded shaft 214 is aligned with the pilot hole and extends through the hybrid hole 102 A with the shaft contacting, but not actively engaging the threads on the side of the hole 102 A. A pair of reference lines 242 , 244 denotes the position of the bone 240 with respect to the bone plate 100 prior to compression. As the screw 210 is inserted farther into the bone 240 , the circumferential surface 216 of the head 212 initially comes in contact with the top of the hole 102 A.
When the circumferential surface 216 of the head 212 comes in contact with the top of the hole 102 A, further insertion of the head is operative to push the head against the distal wall of the hole. This causes the position of the bone plate 100 to shift distally with respect to the bone 240 , thereby creating a compressive force on the bone in the distal direction. As can be seen in FIG. 12 , the reference lines 242 , 244 are no longer aligned, as the reference mark 242 for the plate 100 has shifted distally with respect to the reference mark for the bone 240 .
Referring to FIGS. 13 and 14 , the hybrid holes 102 A of the exemplary bone plate 100 may be utilized to receive a locking screw 180 , such as a variable angle locking screw, in order fix the position of the bone plate 100 with respect to the bone 240 where screw angles other than perpendicular may be desired. In exemplary form, a bone or bone fragments 240 is mounted to the bone plate 100 using a combination of compression and locking screws 210 , 180 . Presuming a surgeon finds it desirable to mount the plate 100 to the bone 240 using a locking screw at an angle other than perpendicular (perpendicular could also be used as well), a pilot hole may be initially drilled. By way of example, the pilot hole is angled based upon the orientation of the bone or bone fragments 240 . After the hole is drilled, a locking screw 180 is inserted through the hole 102 A so that the smaller diameter threaded shaft 184 is aligned with the pilot hole. Thereafter, the locking screw 180 is rotated to fasten the screw to the bone 240 , while at the same time pulling the head 182 into contact with the bounds of the hole 102 A. Specifically, the threads 190 of the screw head 182 engage the threads 120 on the interior of the hole 102 A in order to lock the angular position of the screw head (and screw) with respect to the bone plate 100 .
It should be noted that the dimensions set forth for the exemplary embodiments are just that, exemplary. Deviations from these dimensions may be made without departing from the scope and spirit of the instant disclosure. For example, the holes 102 may have an upper diameter larger or smaller than 0.205 inches. Likewise, the holes may not necessarily have a circular cross-section at any point. Moreover, the holes may generally take on any dimensions that provides for dual functionality and use as both a compression hole and a locking hole.
Following from the above description and invention summaries, it should be apparent to those of ordinary skill in the art that, while the methods and apparatuses herein described constitute exemplary embodiments of the present invention, the invention contained herein is not limited to this precise embodiment and that changes may be made to such embodiments without departing from the scope of the invention as defined by the claims. Additionally, it is to be understood that the invention is defined by the claims and it is not intended that any limitations or elements describing the exemplary embodiments set forth herein are to be incorporated into the interpretation of any claim element unless such limitation or element is explicitly stated. Likewise, it is to be understood that it is not necessary to meet any or all of the identified advantages or objects of the invention disclosed herein in order to fall within the scope of any claims, since the invention is defined by the claims and since inherent and/or unforeseen advantages of the present invention may exist even though they may not have been explicitly discussed herein. | A bone plate including a combination locking and compression screw hole having a top opening and a bottom opening, the top opening being generally circular and including a widthwise dimension and a lengthwise dimension normal to the widthwise dimension, where an interior wall of the bone plate extends between the top opening and the bottom opening, where at least a portion of the interior wall proximate the top opening is threaded, and where at least one of the widthwise dimension and the lengthwise dimension is decreased between the top opening to the bottom opening, while the other of the widthwise dimension and the lengthwise dimension does not substantially decrease between the top opening and the bottom opening. The instant disclosure also includes a method of forming a bone plate comprising: (a) fabricating a bone plate to include a first through hole, where at least one of a width and a length of the hole changes along a depth of the hole; (b) plunge milling an interior surface of the bone plate demarcating the first through hole to remove at least a portion of the bone plate to increase at least one of the width and the length of the through hole; and (c) threading at least a portion of the first through hole. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a decorative refractory tile and it's method of use.
Fireplaces are commonplace in North American homes. However, the majority of fireplaces are not used to consistently provide a source of heat for the building. Most are used as a decorative addition to the building and are occasionally used as a source of “mood” lighting and heating. Conventional fireboxes (the interior cavity of a fireplace) see temperatures in the range of 1000-1200° F., and as such are built and lined with a special refractory brick. This brick is able to withstand these temperatures with a minimal of cracking, distortion and spalling under rapid temperature change, and it's structural strength must hold up well under rapid temperature changes. Refractory brick has the highest thermal conductivities of bricks. It possesses a high resistance to erosion from ash-laden gases and to the fluxing action of molten slag.
The standard size of fire-brick is 9×4.5×2.5 in. Although it can be glazed, it is an uncommon practice in the industry. Therein lies the problem—aesthetics. In an upper end home or commercial structure, the lavish surroundings do not aesthetically blend well with a huge visible wall section primarily composed of uniform brick. Simply stated, the demanding consumer of today wants more.
This new decorative tile utilizes a specially formulated clay body that undergoes dehydration and vitrification by firing in a specific manner with respect to temperature, time and rate of temperature increase, to yield a thin, refractory tile that has the ability, to withstand the temperatures encountered in a conventional firebox or fireplace. This tile can be sized and shaped within certain dimensional ranges, so as allow them to present patterns, designs or even pictures on the sides, floor and back of the firebox. It can be colored with heat resistant glazes, stains and oxides.
Such refractory tile allows owners of both closed and open fireplaces, to line the refractory brick interior of their fireboxes with a decorative tile. This tile is set into place in much the same manner as traditional tiles are set with the exception that they must be affixed to the brick using special refractory mortars. When this tile is crafted by one with an artistic flair, aesthetically favorable fireboxes can be created thereby overcoming the abovementioned drawbacks.
SUMMARY OF THE INVENTION
In accordance with the invention, an object of the present invention is to provide a decorative refractive tile that can be affixed to a firebox to present an aesthetically appealing visual array. The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new method of making and using a refractive tile adapted for the lining of fireboxes, which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art, either alone or in any combination thereof.
It is another object of this invention to provide a clay body formulation and method of firing that yields a refractory tile that can withstand rapid, extreme temperature changes, as would be encountered within a fireplace, without cracking or spalling.
It is a further object of this invention to provide a method of making and applying decorative refractory tile to a refractory brick lined firebox.
It is still a further object of this invention to provide for a refractive tile that can be shaped, colored and simply and economically fabricated.
The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation, together with further advantages and objects thereof, may best be understood by reference to the following description taken in connection with accompanying drawings wherein like reference characters refer to like elements. Other objects, features and aspects of the present invention are discussed in greater detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of a moist clay body formed into a workable parallelepiped formation;
FIG. 2 is an top view of the clay body being flattened to a planar configuration in a thickness box;
FIG. 3 is a top view of the flattened, planar clay body being gut into geometric tiles;
FIG. 4 is a perspective view of a triangular cut clay body;
FIG. 5 is a front view of a firing kiln in which the tiles are dehydrated and vitrified;
FIG. 6 is a front view showing the application of a color bearing surface coating onto a vitrified refractory tile;
FIG. 7 is an side view of an elongate refractive tile that has a fused surface coating;
FIG. 8 is an side view of a geometric shaped tile with a fused surface coating;
FIG. 9 is a front view of a fireplace with an array of decorative refractory tile applied to the back and side walls of the firebox; and
FIGS. 10-12 are front views of geometric pattern arrays into which the refractory tile can be arranged.
FIG. 13 is a chart depicting an 8.5 Hour Firing Heatup Rate (Temperature vs Time)
DETAILED DESCRIPTION
Clay is finely crystalline, hydrous silicates formed from weathering of such silicate minerals as feldspar, pyroxene, and amphibole. Most common clay minerals belong to kaolinite, montmorillonite, and illite groups. Clay derives from the disintegration of granite and other feldspathic or pegmatite rocks, which as they decompose, deposit alumina and silica particles. Alumina and silica when combined with water form pure clay having the formulae Al 2 O 3 .2H 2 O.2SiO 2 . Different characteristics are imparted by the addition of differing chemicals and the relative sizes of the constituents. Of particular interest to this invention are fireclays.
Fireclays are clays that are high in iron and capable of high temperature firing and have the ability of withstanding repeated thermal shock without cracking. They generally contain iron, calcium or feldspar and may also be high in flint, alumina, silica, or alumina and silica. Clay shrinkage generally ranges from 5 to 12 percent in the drying stage and another 8 to 12 percent in the firing. Overall most clays have a total shrinkage of 13 to 24 percent. Fireclays and the product described herein are not very plastic and thus have low shrinkage in the firing process due to the substitution of chemicals for some of the silica. They are highly refractory having a dense vitrification, and have a higher firing temperature range than most clay bodies. Generally they are course grained which improves the structural integrity.
Since this refractory tile is destined to be bonded to a refractory brick, it must possess many of the same physical qualities of refractory brick. They both must have a high resistance to erosion by ash-laden gases and to the fluxing action of molten slag, and cannot spall badly or crack under repeated rapid temperature changes. Both are baked in the kiln until partly vitrified. The tile is generally glazed so as to impart an aesthetic appeal.
Like a refractory brick, refractory tile is built mainly to withstand temperature. This does not usually accompany resistance to heat flow; in fact, this tile and refractory bricks have some of the highest thermal conductivities. This high thermal conductivity is the most important feature of refractory materials. The breaking or cracking of non refractory tiles is most commonly caused by thermally-related fractures caused by tensions within the mass of the tile. These fractures are caused by different degrees of dilation within the tile mass caused by the absorption of different amounts of heat by thermally non-conductive materials within the tile. Using a thermally conductive material for the refractory tile allows for more uniform heat absorption, thus allowing the tile to dilate uniformly and avoid the internal tensions which lead to fracture.
The decorative refractory tile of the present invention, is formed by thoroughly mixing 20-30% by weight of water with the following composition of dry powder of particles that have been sized to pass through a 200 BSS mesh. (ASTME Standard 11-61, or a 74 micron aperture) Note, the amount of water used is a matter of choice and is dictated by the desired workability of the clay body by the tile maker. There is no precise amount of water in this 20-30% range, nor is it relevant, as the water is driven out of the cut tile shapes during the elevated temperature period (firing) in the kiln. Generally, there is only a 3% variance in the relative percentages of the components of the clay body listed herein, however up to a 5% variance has shown to be tolerable for the fabrication of a proper refractory tile.
Dry Chemical Composition of Refractory Tile Base
Chemical Name
Allowable Wt
Component
(Common Name)
Weight %
% Range
Na 2 O
Sodium Oxide
0.80
.76-.84
(Soda)
K 2 O
Potassium Oxide
1.12
1.064-1.176
(Potash)
MgO
Magnesium Oxide
0.15
0.1425-0.1575
(Magnesia)
CaO
Calcium Oxide
0.16
0.152-0.168
(Quicklime)
Al 2 O 3
Aluminum Oxide
28.52
27.094-29.946
(Alumia)
Fe 2 O 3
Ferric Oxide
1.11
1.0545-1.1655
(Iron)
SiO 2
Silicon Dioxide
66.8
63.46-70.14
(Silica)
TiO 2
Titanium
0.79
0.7505-0.8295
Dioxide
(Titania)
P 2 O 5
Phosphorus
0.02
0.019-0.021
Pentoxide
Organic
Loss On
0.53
0.5035-0.5565
Impurities
Ignition
Organics
(LOI's)
Total
100
The above chemical components are mixed with the appropriate amount of water (preferably 26%) in a pug mill, which uses mechanical fingers and pressure to create uniform consistency in the clay body. The pug mill also “wedges” the clay to eliminate air pockets. Once the above composition is thoroughly blended, the resultant mixture makes a clay body that can be dehydrated and vitrified in a kiln, with an 8% shrinkage, to form a refractory tile when formed and treated according to the following procedures.
First, once the clay body is mixed appropriately, it is formed into a workable parallelepiped formation 2 . (Reference FIG. 1 ) Second, the clay body is cut into generally planar flakes with a wire tool and flattened in a thickness box 4 comprised of a planar bottom 6 bounded by uniform thickness exterior rails 8 over which a rolling pin 10 is worked until the clay body is of a uniform planar configuration 12 having a specified thickness. (Reference FIG. 2 )
Since approximately 8% shrinkage in volume occurs during the firing process (with a 26% by weight water addition), allowance must be made to achieve the end desired thickness of tiles. The tiles can only be fabricated in certain ranges for both practical reasons such as shipping, and to maintain their refractive tile physical properties. Experimentation has shown that the desired range of finished tile thickness is between ¼ of an inch and ⅝ of an inch. The preferred range is ½ of an inch plus or minus 1/16 of an inch. (⅝ of an inch thick cut, wet tiles will shrink to between 5/16 and 7/16 in thickness, depending upon the geometric shape and the amount of water in the original clay body.) Below ¼ inch in thickness leads to a tile which is too fragile and unable to handle the repeated thermal shock encountered in a firebox.
Similarly, the geometric shapes that the tiles are formed into are limited to certain dimensional sizes. Testing has shown that with the nominal ½ inch thick finished tiles, tiles made in the following dimensions are the most practical: ½ inch wide by 8 inch long; ½ inch by ½ inch square; 4 inches by 3 inches rectangular; and up to 5 inches in curved configuration. While it is possible to achieve larger sizes, these require specialized procedures and equipment. Such would be known to one skilled in the art. Typically, the geometric configurations are planned to form intricate pieces of such designs as illustrated in FIGS. 10 , 11 and 12 . A commonly used tile that has undergone extensive testing is elongate tile 24 (Reference FIG. 7 ) that can be used to form such aesthetically appealing patterns as illustrated in FIG. 12 .
Once the clay body is brought to the desired thickness, a pattern is laid over the planar clay configuration 12 and the geometric shapes 14 are cut out with a cutting tool 18 . (Reference FIG. 3 . The edges of a cut tile are rounded 16 by hand to prevent later breaking or chipping and to impart aesthetic qualities. (Reference FIG. 7 ) The cut tiles are then put into a kiln 20 (Reference FIG. 5 ) that is eventually fired to between 2228° F. and 2273° F. (designated as Orton cone 7 - 8 ) following the heatup rate illustrated in FIG. 13 . (The Orton series of cones is a reference scale of temperatures well known in the ceramics industry.) The cut tiles 14 are laid flat, do not touch other tiles and are not flipped or rotated during this process. Depending upon the look desired, the cut tiles 14 may or may not have a surface treatment 16 (Reference FIG. 6 ) such as a glaze, a stain, an oxide; or a slip. This is discussed in more detail herein.
Clay undergoes two basic stages in firing; dehydration and vitrification. In a kiln, with the rising temperature, the excess absorbed interlayer water molecules as well as the adsorbed interstitial water molecules (chemical water) are transported to the surface by capillary action. The absorbed interlayer water molecules are the first evaporated and at about 660° F. the chemical water, which cannot be removed by any amount of drying below that temperature, begins to be driven off. The dehydration process is essentially complete at about 1100° F. and the clay becomes anhydrous, or free of all water. Beyond this point incipient sintering begins; the molecules of silica and alumina begin to collapse together, partially filling the voids left by the evaporated water and creating a relatively firm bond which gives the fired clay body its hardness and strength. At temperatures above 1100° F., the clay body loses it's structure becoming “amorphous”. By this time all organic impurities, (termed Loss on Ignition or LOI products) are driven out. Recrystallization may occur at temperatures above 1832° F. Once above 1832° F. the clay reaches a temperature which is above its stability range and the minerals may not have time to alter and recrystallize instead becoming fused into an amorphous solid. This “vitrified,” or glassy solid is not absorbent and can never return to its original plastic state. Refractory brick or tile must have a minimum fusion point higher than 1,600° F.
During dehydration the water is driven off. For this specific clay composition forming the refractory tile, this amounts to about 8% shrinkage although most pottery and clay based firings undergo about 14% shrinkage.
The firing process requires an approximately 8 and ½ hour firing. (Reflected in Table 1 and FIG. 13 ) While the heatup rate may be compressed to as low as approximately 3 hours, (reflected in Table 2) any quicker heating may result in explosion.
TABLE 1 Heatup Rates for 8.5 Hour Firing Temperature (F. °) Time (Hours) 65 0 250 1.2 1000 2.7 1150 3.6 1694 5.4 1946 7.5 2276 8.5
The critical feature is the end temperature achieved. This attains a level of vitrification that imparts the desired refractory qualities to the tiles. The tiles are removed when they are less than 100° F. but this is for handling purposes only as they may be removed after the critical temperature has been reached. It should be noted that most modern kilns are computer controlled and have various preset heatup rates. While these vary between manufacturers, there are industry known limitations in the approach to final temperature. While the depicted heatup rate is representative of the inventor's kiln, it is not the precise interval heatup rates that are critical but rather the overall heatup rate as indicated by the slope of the temperature vs time line.
TABLE 2
Heatup Rates for 3.0 Hour Firing
Temperature (F. °)
Time (Hours)
650
0
250
0.4
1000
1.0
1150
1.3
1694
1.9
1946
2.7
2276
3.0
A typical approach to final temperature as used in the aforementioned process would be accomplished at the following rates: 200° F. per hour from ambient to 250° F.; 400° F. per hour from 250° F. to 1000° F.; 180° F. per hour from 1000° F. to 1150° F.; 300° F. per hour from 1150 to 1694° F.; and 120° F. per hour from 1694° F. to 2273° F.
Once cooled, the tiles 14 may be applied in the firebox area (Reference FIG. 9 ) of a fireplace 26 , on the side walls 30 , back walls 32 or floor 28 in the same manner in which ceramic wall tiles are set, except for the bonding and grouting agents. A wet, air setting high strength mortar for temperatures up to 3000° F. must be used to set the tiles. Sairmix 7A manufactured by RHI Refractories has been tested satisfactorily for this application and found to perform satisfactorily in accordance to the below described procedures. Such products generally require 24 hours to dry. Similarly, a wet, air setting, thick patching mortar for temperatures up to 3200° F. may be used as a grout. It must have excellent bonding capabilities as well as low shrinkage and able to span up to ½ inch wide joints 34 . (Reference FIG. 12 ) Greenpatch 421 from RHI Refractories has been tested and found to perform satisfactorily in accordance to the below described procedures. Such products generally require 24 hours to dry.
A cool unglazed tile, once removed from the kiln, is naturally slightly porous. The purpose of a surface treatment 16 is threefold: to prevent porosity, to resist chemical action, and to color. A surface treatment can be added in any of the following ways: by glazing; by staining; by surface application of an oxide; or by surface application of a slip. (A slip is a thin coat of finely ground up naturally colored clay that has been diluted to a paint like working consistency with water.) All of these surface treatments when undergoing a firing, are fused to the refractory tile forming a vitrified, either glass like or matte surface finish. All but the glazes generally are applied to the final visual surfaces of the cut, wet tiles 14 with a brush 32 (Reference FIGS. 6 and 8 ) before the first firing. For best results, glazes need to be applied to the cooled refractory tiles and then the tiles fired in the kiln a second time to properly fuse the glaze to the tile. Although it is possible under controlled conditions to apply a glaze prior to the first firing of the tiles, it often results in a crazed finish or a finish replete with hairline cracks and non uniform color depth. These surface treatments often include glass to begin with, in a finely powdered state; or the fused components of glass. Sometimes they are merely the alkaline or metallic-salt part of glass, which finds its silica in the clay of the tile itself.
In the absence of any ASTM testing procedures, two separate thermal shock tests were devised and utilized in the development of the refractory tile. Experimentation has proven that the method outlined above will result in a refractory tile between 3/16 inch and ½ inch thick that can successfully withstand both of the thermal shock tests detailed below without damage:
Thermal Shock Test #1
Raise the tile temperature from ambient 70° F. to 1500° F. in 15 minutes in an electric or gas fired kiln.
Hold tile temperature at 1500° F. for 15 minutes.
Remove tile from kiln and quench immediately in 60° F. water.
Immediately repeat with same tile for 4 more cycles.
Inspect for damage.
Thermal Shock Test #1
Place the tile in an enclosed hardwood burning firebox having a temperature of 1200° F.
Keep tile in this environment for 20 minutes.
Remove tile from firebox and quench immediately in 60° F. water.
Place quenched tile immediately in a freezer for 8 hours.
Immediately repeat with same tile for 2 more cycles.
Inspect for damage.
When the aforementioned clay body is fired as detailed above and the desired surface treat applied, it renders a decorative refractory tile that is capable of withstanding thermal cycling with temperatures up to 2000° F. as well as the harsh environment of a firebox.
The above description will enable any person skilled in the art to make and use this invention. It also sets forth the best modes for carrying out this invention. There are numerous variations and modifications thereof that will also remain readily apparent to others skilled in the art, now that the general principles of the present invention have been disclosed. | The present invention relates to a decorative refractory tile and it's method of use. This decorative tile utilizes a specially formulated clay body that undergoes dehydration and vitrification by firing in a specific manner with respect to temperature, time and rate of temperature increase. This thin, refractory tile has a high thermal conductivity, high structural strength able to maintain a minimal of cracking, distortion and spalling under rapid temperature changes and possesses a high resistance to erosion from ash-laden gases encountered in a conventional fireplace.
This tile can be colored with heat resistant glazes, stains and oxides and sized or shaped within certain dimensional ranges, so as allow it to present patterns, designs or even pictures on the sides, floor and back of the firebox.
When this tile is crafted by one with an artistic flair, and affixed to the walls, floor or sides of a firebox, aesthetically favorable fireplaces can be created. | 2 |
TECHNICAL FIELD
[0001] This disclosure generally relates to a tone wheel configured to interact with a speed sensor. More particularly, the tone wheel is for a planetary gearset and is configured to attach via an interference fit with a gear of the planetary gearset.
BACKGROUND
[0002] Modern vehicles include a plethora of electronic sensors that provide information to one or more controllers. One such sensor is a rotational speed sensor that detects the speed of a rotating component. A tone wheel can either be formed integrally with the rotating component or attached to it. The tone wheel includes slots, grooves, or other surface features. As the rotating component rotates, the surface features of the tone wheel also rotate and an electrical pulse is generated each time a surface feature rotates past the sensor.
[0003] Transmissions in vehicles have many rotating parts, and a speed of the rotating parts is helpful in many different control settings. One example of a mechanism in a transmission with rotating parts is a planetary gearset. Planetary gearsets include a sun gear, planet gears, a planet carrier, and a ring rear. Any one of these gears can be configured to rotate about the central axis. The detected rotating speed of one of these gears can typically make the rotational speeds of the other gears known through the given gear ratio of the planetary gear set. For example, a tone wheel may be provided about and secured to the carrier to make the speed of the carrier known; hence, the speed of the sun and planet gears also known.
SUMMARY
[0004] In one embodiment, a transmission includes a planetary gearset having a carrier. An annular-shaped tone wheel is connected to the carrier, and has an inner-diameter surface and an outer-diameter surface. The tone wheel further includes a pair of legs extending inward from the inner-diameter surface. An interference fit is provided between the legs and the carrier.
[0005] In another embodiment, a tone wheel for a transmission of a vehicle is provided. The tone wheel has a body having a convex outer surface, a concave inner surface, and a plurality of flanges. The outer surface has a plurality of surface features arranged annularly thereon about a central axis. The flanges extend inward from the inner surface toward the central axis. Each flange has a mating surface for contacting a carrier. The mating surface is axially offset from the inner surface of the body.
[0006] In yet another embodiment, a method of assembling a planetary gearset is provided. The method includes connecting a plurality of planet gears to a carrier, wherein the carrier has a plurality of surfaces each located between adjacent planet gears. The method also includes press-fitting a pair of legs of a tone wheel onto each surface to secure the tone wheel to the carrier.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a front view of a planetary gearset with an attached tone wheel;
[0008] FIG. 2 is a front view of the tone wheel of FIG. 1 in isolation;
[0009] FIG. 3 is a perspective view of the tone wheel of FIG. 2 ;
[0010] FIG. 4 is a perspective view of a portion of the planetary gearset, illustrating the interference fit between the tone wheel and a carrier of the planetary gearset; and
[0011] FIG. 5 is a perspective view of the planetary gearset and attached tone wheel, along with an accommodating sensor.
DETAILED DESCRIPTION
[0012] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.
[0013] Referring to 1 - 4 , a planetary gear set 10 for a transmission of a vehicle is illustrated. The planetary gearset 10 includes a sun gear (not shown) that shares a central axis with that of the gearset 10 . Radially outward from the sun gear are three planet gears 14 . The planet gears 14 include meshing teeth 16 that correspond to teeth on the sun gear. As the sun gear rotates, each of the planet gears 14 rotates about its own respective axis.
[0014] A carrier 18 is driveably connected to each of the planet gears 14 . The carrier 18 can transfer rotational movement to and from the planet gears 14 such that the planet gears 14 can rotate in unison about the sun gear. As the carrier 18 rotates about the central axis, the planet gears 14 rotate about the central axis and their own individual axis as well.
[0015] A tone wheel is illustrated generally at 20 , and shown in isolation in FIGS. 2 and 3 . The tone wheel 20 couples to the planet carrier 18 to rotate with the carrier with the same rotational speed. Functioning as part of a rotational speed sensor, rotation of the tone wheel 20 is sensed to determine the rotational speed of the carrier 18 and thus the rotational speed of other components within the planetary gearset through known mathematical gear relationships.
[0016] The tone wheel 20 is generally round in shape and therefore includes a general diameter. The tone wheel 20 includes an outer-diameter surface 22 . A continuous series of grooves, holes, undulations, or other such surface features 24 are stamped, formed, or otherwise provided on the outer-diameter surface. As will be described below with reference to FIG. 5 , a pulse is created by a sensor when these surface features pass by the sensor. The speed or frequency of the pulse corresponds to the rotational speed of the tone wheel 20 .
[0017] Utilizing a tone wheel 20 enables a vehicle controller to determine the rotational speed of the carrier and other portions of the planetary gearset 10 . Accurate determination of the rotational speed of these components is useful for knowing the speeds going into and out of the planetary gear set.
[0018] During assembly of the planetary gearset 10 , the tone wheel 20 must be installed onto the carrier 18 after the planet gears 14 and the carrier 18 are assembled together. Welding the tone wheel 20 to the carrier 18 can increase the risk of contamination getting into the planet gears and bearings of the planetary gearset 10 . And, typical press-fit applications deform surfaces of the pressed part to assure a tight fit. Precise location and clearance between the tone wheel 20 and the associated sensor is imperative for accurate speed readings.
[0019] According to the present disclosure, the tone wheel 20 of the planetary gearset 10 is provided with structure that enables it to be press-fit onto the carrier 18 . This eliminates the need for the time, expense, and potential contaminants that come naturally with welding.
[0020] To accomplish the press-fit, the tone wheel 20 includes an inner-diameter surface 30 with a plurality of legs 32 extending therefrom. The legs 32 are relatively flexible in that they can flex relative to the inner- and outer-diameter surfaces 22 , 30 of the tone wheel 20 . This allows the legs 32 to be pressed onto the carrier 18 and deform to assure a secure press-fit without deforming the outer-diameter surface 22 on which the surface features 24 are provided. In other words, the legs 32 provide a surface to be press-fit onto an associated surface of the carrier 18 while maintaining the shape of the outer-diameter surface 22 .
[0021] The legs 32 can come in pairs. As shown in FIG. 1 , for example, the tone wheel 20 includes three pairs of legs 32 , with each pair contacting one corresponding contact region 34 of the carrier 18 . This embodiment is beneficial for a three-planet-gear gearset in which the carrier includes three regions that extend over and between two of the planet gears 14 . As illustrated in FIG. 1 , the contact regions 34 can be flanges that extend from an area axially-outward of the planets 14 toward and in-between the planets 14 . The legs 32 can contact opposing sides of this contact region 34 of the carrier 18 . Between two of the pairs of legs 32 are concave regions 36 of the inner-diameter surface 30 . This provides clearance for the individual planet gears 14 to rotate.
[0022] The tone wheel 20 shown in the figures is but one embodiment in which the tone wheel 20 has three sets or pairs of legs 32 for each of three contact regions 34 of the carrier. This corresponds to the planetary gearset having three planet gears 14 . However, it should be understood that more or less than three planet gears 14 can be provided, and as such, the carrier 18 can be designed to have more or less than three contact regions 34 that extend between a respective pair of planet gears 14 . This can lead to a design of the tone wheel 20 having more or less than three pairs of legs 32 . For example, the planetary gearset 10 may have five planet gears, and the tone wheel 20 can include five pairs of legs 32 , with each pair of legs 32 contacting one respective contact region of the carrier.
[0023] To make an interference-fit or press-fit secure between the tone wheel 20 and the carrier 18 , a mechanical press (not shown) may be utilized. The press can be hydraulically equipped or otherwise capable of providing a large press force to the tone wheel 20 . The mechanical press can be operated to press the tone wheel 20 along the carrier 18 in the direction of the central axis of the planetary gearset 10 . As the tone wheel 20 is pushed along the carrier, the legs 32 are the first and only part of the tone wheel 20 to contact the carrier 18 . The legs 32 deform slightly outward from the central axis and provide resistance against the contact regions 34 of the carrier 18 . When the press is finished pressing the tone wheel 20 onto the carrier 18 , a secure interference fit is provided between the legs 32 and the contact region 34 .
[0024] As the legs 32 come in pairs, each pair of legs 32 provide an interference fit with the carrier 18 at two separate locations. Each pair of legs provides two loading points per contact region 34 of the carrier 18 . If three pairs of legs 32 are provided, as illustrated in the figures, then six different loading points are provided. With six different loading points, the mechanics of the deflection of forces with the interference fit is generally hexagonal in shape. If, in contrast, the tone wheel were to have single weld spots or the like to secure the tone wheel to the carrier, only three loading points would be provided and therefore the mechanics of deflection would be triangular in shape. Utilizing pairs of legs 32 to have additional loading points reduces the magnitude of deflection forces at each loading point by spreading the load to additional load points.
[0025] To further assist with a secure press-fit, the legs 32 are axially offset from the main portion of the tone wheel 20 . In particular, the tone wheel 20 includes an interior body portion 40 that extends from the inner-diameter surface 30 . This interior body portion 40 may extend about the entire inner-diameter surface 30 , and also includes other regions such as the concave regions 36 . The legs 32 extend from the interior body portion 40 and away from the inner-diameter surface and toward the central axis of the tone wheel 20 . The legs 32 also extend in a direction along the central axis from the interior body portion 40 such that the legs 32 are axially offset from the main body portion 40 . This provides the legs 32 with a contact surface 42 that is axially offset from the main body portion 40 for engaging with the contact region 34 . Thus, the point of engagement between the carrier 18 and the tone wheel 20 can be axially offset from the interior body portion 40 and inner-diameter surface 30 of the tone wheel 20 . Having an axially-offset location of contact allows the tone wheel to bend and yield during fitting in a non-functioning area.
[0026] As explained above, the legs 32 provide a mechanism to allow an interference fit between the carrier 18 and the tone wheel 20 with minimal or no distortion of the outer-diameter surface 22 of the tone wheel itself during assembly. This enables the tone wheel 20 to maintain a critically-accurate and relatively small clearance between the tone wheel 20 and an accommodating speed sensor 50 at all locations along the outer-diameter surface 22 . This is shown in FIG. 5 . When the tone wheel 20 spins with rotation of the carrier 18 , a pulse is generated by the sensor 50 when the surface features 24 pass by the sensor 50 . The speed or frequency of the pulse corresponds to the rotational speed of the tone wheel 20 . A gap or clearance 52 between the sensor 50 and these surface features 24 can be about 1 mm, and between 0.5 and 1.5 mm in preferred embodiments. Maintaining the size and consistency of this gap 52 as the tone wheel 20 spins is important for accuracy of speed readings. The legs 32 assure the outer-diameter surface 22 is not distorted during the process of fitting the tone wheel 20 to the carrier 18 . This maintains the gap 52 at a preferable size.
[0027] To further a secure fit between the tone wheel 20 and the carrier 18 , nubs 54 may extend away from each leg 32 . The nubs can be arranged such that when the tone wheel 20 is fitted onto the carrier 18 , each contact region 34 can be held within a pair of the nubs 54 on either end of the contact region. The nubs can also be used as locating features to quickly align the tone wheel 20 to the carrier prior to press-fitting.
[0028] While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention. | A planetary gearset is provided in a transmission for a vehicle. The planetary gearset includes a carrier that rotates about the axis. Tone wheels can be used as part of a speed-sensing mechanism in which the tone wheel includes surface features on an outside surface, and a speed sensor senses the surface features as they rotate about the axis and past the speed sensor. The tone wheel is connected to the carrier via a press-fit or interference-fit. To do so, the tone wheel includes legs or flanges that extend inward from an inner surface of the tone wheel. The legs or flanges flex as the tone wheel is pressed onto the carrier. The legs or flanges securely attach the tone wheel to the carrier. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to internal combustion engines, and, more particularly, to exhaust gas recirculation systems in such engines.
BACKGROUND OF THE INVENTION
[0002] An internal combustion (IC) engine may include an exhaust gas recirculation (EGR) system for controlling the generation of undesirable pollutant gases and particulate matter in the operation of internal combustion engines. EGR systems primarily recirculate the exhaust gas by-products into the intake air supply of the internal combustion engine. The exhaust gas which is reintroduced to the engine cylinder reduces the concentration of oxygen therein, which in turn lowers the maximum combustion temperature within the cylinder and slows the chemical reaction of the combustion process, decreasing the formation of nitrous oxides (NOx). Furthermore, the exhaust gases typically contain unburned hydrocarbons which are burned on reintroduction into the engine cylinder, which further reduces the emission of exhaust gas by-products which would be emitted as undesirable pollutants from the IC engine.
[0003] An IC engine may also include one or more turbochargers for compressing a fluid which is supplied to one or more combustion chambers within corresponding combustion cylinders. Each turbocharger typically includes a turbine driven by exhaust gases of the engine and a compressor which is driven by the turbine. The compressor receives the fluid to be compressed and supplies the fluid to the combustion chambers. The fluid which is compressed by the compressor may be in the form of combustion air or a fuel and air mixture.
[0004] The operating behavior of a compressor within a turbocharger may be graphically illustrated by a “compressor map” associated with the turbocharger in which the pressure ratio (compression outlet pressure divided by the inlet pressure) is plotted on the vertical axes and the flow rate is plotted on the horizontal axes. In general, the operating behavior of a compressor is limited on the left side of the compressor map by a “surge line” and on the right side of the compressor map by a “choke line”. The surge line basically represents “stalling” of the air flow at the compressor inlet. With too small a volume flow and too high a pressure ratio, the flow will separate from the suction side of the blades on the compressor wheel, with the result that the discharge process is interrupted. The air flow through the compressor is reversed until a stable pressure ratio by positive volumetric flow rate is established, the pressure builds up again and the cycle repeats. This flow instability continues at a substantially fixed frequency and the resulting behavior is known as “surging”. The choke line represents the maximum centrifugal compressor volumetric flow rate, which is limited for instance by the cross-section at the compressor inlet. When the flow rate at the compressor inlet or other location reaches sonic velocity, no further flow rate increase is possible and choking results. Both surge and choking of a turbocharger compressor should be avoided.
[0005] When utilizing EGR in a turbocharged diesel engine, the exhaust gas to be recirculated is preferably removed upstream of the exhaust gas driven turbine associated with the turbocharger. In many EGR applications, the exhaust gas is diverted by a poppet-type EGR valve directly from the exhaust manifold. The percentage of the total exhaust flow which is diverted for introduction into the intake manifold of an internal combustion engine is known as the EGR rate of the engine.
SUMMARY OF THE INVENTION
[0006] The present invention provides an EGR system which is configured such that exhaust gas is circulated to the intake manifold, or, alternatively, charge air is bypassed in a reverse direction through the EGR system to the turbocharger.
[0007] The invention comprises, in one form thereof, an internal combustion engine including a block defining at least one combustion cylinder. An intake manifold is fluidly coupled with at least one combustion cylinder, and an exhaust manifold is also fluidly coupled with at least one combustion cylinder. An exhaust gas recirculation system is fluidly coupled between the exhaust manifold and the intake manifold. A turbocharger includes a variable geometry turbine fluidly coupled with the exhaust manifold. The variable geometry turbine is movable to a first position effecting fluid flow of exhaust gas from the exhaust manifold to the intake manifold, and movable to a second position effecting fluid flow of charge air to the variable geometry turbine.
[0008] The invention comprises, in another form thereof, an exhaust gas recirculation system for an internal combustion engine including an intake manifold having an inlet, an exhaust manifold having an outlet, and a turbocharger coupled with the exhaust manifold outlet. The exhaust gas recirculation system includes at least one fluid line for interconnecting the exhaust manifold outlet and the intake manifold inlet; and a pressure differential generator for selectively generating an EGR flow of exhaust gas through the at least one fluid line from the exhaust manifold outlet to the intake manifold inlet, and a reverse EGR flow of charge air through the at least one fluid line to the turbocharger.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a schematic illustration of an embodiment of an internal combustion engine of the present invention; and
[0010] FIG. 2 is a graphical illustration of a compressor map for the turbocharger shown in FIG. 1 , illustrating the effect of the present invention on the compressor map.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0011] Referring now to the drawings, and more particularly to FIG. 1 , there is shown an embodiment of an IC engine 10 of the present invention, which generally includes a block 12 having a plurality of combustion cylinders 14 , intake manifold 16 , exhaust manifold 18 , charge air cooler 20 , turbocharger 22 , EGR valve 24 and EGR cooler 26 . In the embodiment shown, IC engine 10 is a diesel engine which is incorporated into a work machine, such as an agricultural tractor or combine, but may be differently configured, depending upon the application.
[0012] Block 12 is typically a cast metal block which is formed to define combustion cylinders 14 . In the embodiment shown, block 12 includes six combustion cylinders 14 , but may include a different number depending upon the application. Intake manifold 16 and exhaust manifold 18 are also typically formed from cast metal, and are coupled with block 12 in conventional manner, such as by using bolts and gaskets. Intake manifold 16 and exhaust manifold 18 are each in fluid communication with combustion cylinders 14 . Intake manifold 16 receives charge air from charge air cooler 20 at intake manifold inlet 28 , and supplies charge air (which may be air or a fuel/air mixture) to combustion cylinders 14 , such as by using fuel injectors (not shown).
[0013] Similarly, exhaust manifold 18 is in fluid communication with combustion cylinders 14 , and includes an outlet 30 from which exhaust gas from combustion cylinders 14 is discharged to turbocharger 22 .
[0014] Turbocharger 22 includes a variable geometry turbine (VGT) 32 and a compressor 34 . VGT 32 is adjustably controllable as indicated by line 36 , and includes an actuatable element which is controlled electronically using a controller (not shown). For example, VGT 32 may be actuated by changing the position of turbine blades, a variable size orifice, or other actuatable elements. The turbine within VGT 32 is driven by exhaust gas from exhaust manifold 18 , and is exhausted to the environment, as indicated by arrow 38 .
[0015] VGT 32 mechanically drives compressor 34 through a rotatable shaft 40 . Compressor 34 is a fixed geometry compressor in the embodiment shown. Compressor 34 receives combustion air from the ambient environment as indicated by line 42 , and discharges the compressed combustion air via line 44 to charge air cooler 20 . As a result of the mechanical work through the compression of the combustion air, the heated charge air is cooled in charge air cooler 20 prior to being introduced at inlet 28 of intake manifold 16 .
[0016] EGR valve 24 and EGR cooler 26 are part of an EGR system which also includes a first fluid line 46 , second fluid line 48 and third fluid line 50 . The term fluid line, as used herein, is intended broadly to cover a conduit for transporting a gas such as exhaust gas and/or combustion air, as will be understood hereinafter.
[0017] First fluid line 46 is coupled at one end thereof with a fluid line 52 interconnecting exhaust manifold outlet 30 with VGT 32 . First fluid line 46 is coupled at an opposite end thereof with EGR cooler 26 . Second fluid line 48 fluidly interconnects EGR cooler 26 with EGR valve 24 . Third fluid line 50 fluidly interconnects EGR valve 24 with fluid line 54 extending between charge air cooler 20 and inlet 28 of intake manifold 16 .
[0018] In the embodiment shown in FIG. 1 , first fluid line 46 is fluidly coupled with fluid line 52 extending between exhaust manifold 18 and VGT 32 . However, it will also be understood that first fluid line 46 may be fluidly coupled directly with exhaust manifold 18 for certain applications. Similarly, third fluid line 50 is fluidly coupled with fluid line 54 interconnecting charge air cooler 20 and inlet 28 of intake air manifold 16 . However, it will also be understood that third fluid line 50 may be coupled directly with intake air manifold 16 in certain applications.
[0019] During operation, IC engine 10 is operated to recirculate a selective amount of exhaust gas from exhaust manifold 18 to intake manifold 16 using an EGR system defined by first fluid line 46 , EGR cooler 26 , second fluid line 48 , EGR valve 24 and third fluid line 50 . The EGR system could also be defined by first fluid line 46 , EGR valve 24 , second fluid line 48 , EGR cooler 26 , and third fluid line 50 , in that order connecting fluid line 52 to fluid line 54 . A controller selectively actuates EGR valve 24 to provide EGR flow of the exhaust gas in the EGR flow direction indicated by the large directional arrows on first fluid line 46 and third fluid line 50 .
[0020] Conversely, the EGR system is also configured to provide a reverse flow of fluid in the form of charge air from fluid line 54 to fluid line 52 leading to VGT 32 . More particularly, VGT 32 may be controllably actuated to provide a pressure within fluid line 52 which is less than the pressure within fluid line 54 . When EGR valve 24 is opened, charge air thus flows from fluid line 54 through EGR valve 24 and EGR cooler 26 to fluid line 52 , and ultimately to VGT 32 . Under certain operating conditions, it is desirable to mix cooled charge air with the exhaust which is discharged from outlet 30 of exhaust manifold 18 . The reverse flow direction of charge air through the EGR system is indicated by the smaller directional arrows on second fluid line 48 and first fluid line 46 .
[0021] Conventional operation of an EGR system deactivates the EGR system, or prevents any through flow, during engine operating conditions when no EGR flow is desired. On the other hand, the present invention utilizes an EGR system in a reverse flow mode to bypass fresh air around combustion cylinders 14 to VGT 32 during appropriate engine operating conditions when no EGR flow is desired. For this reverse flow to occur, it is apparent that VGT 32 is configured in a way to obtain a positive engine delta pressure (higher intake manifold pressure than exhaust manifold pressure). The process of configuring the turbocharger to obtain a positive engine delta pressure also allows a more efficient operation of turbocharger 22 .
[0022] The present invention has been shown to provide improved fuel efficiency, air to fuel ratio, smoke emissions, and compressor surge margin, as well as reduce exhaust temperatures, at low to intermediate engine speeds when IC engine 10 is delivering moderate to high torque output. Due to these engine performance improvements, maximum engine output torque at certain engine speeds can also be increased, if desired.
[0023] FIG. 2 is a graphical illustration of a compressor map for compressor 34 of turbocharger 22 when using EGR reverse flow of the present invention as described above. The left most line on the curve represents the surge line of the compressor. Using EGR reverse flow with the present invention, the operating point is shifted upward and to the right away from the surge line, as indicated by any particular one of the three arrows. This effectively reduces the possibility of surge of compressor 34 of turbocharger 22 .
[0024] In the embodiment of the present invention described above, IC engine 10 includes a VGT 32 which is controlled to provide a delta engine pressure between intake manifold 16 and exhaust manifold 18 allowing reverse flow through the EGR system. However, it is also possible to use a pressure differential generator in the form of a differently configured turbocharger, such as a turbocharger with a wastegate, a multiple turbocharger system, a multi-stage turbocharger system, or even a fixed geometry turbocharger at low engine speeds.
[0025] Having described the preferred embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims.
Assignment
[0026] The entire right, title and interest in and to this application and all subject matter disclosed and/or claimed therein, including any and all divisions, continuations, reissues, etc., thereof are, effective as of the date of execution of this application, assigned, transferred, sold and set over by the applicant(s) named herein to Deere & Company, a Delaware corporation having offices at Moline, Ill. 61265, U.S.A., together with all rights to file, and to claim priorities in connection with, corresponding patent applications in any and all foreign countries in the name of Deere & Company or otherwise. | An internal combustion engine includes a block defining at least one combustion cylinder. An intake manifold is fluidly coupled with at least one combustion cylinder, and an exhaust manifold is also fluidly coupled with at least one combustion cylinder. An exhaust gas recirculation system is fluidly coupled between the exhaust manifold and the intake manifold. A turbocharger includes a variable geometry turbine fluidly coupled with the exhaust manifold. The variable geometry turbine is movable to a first position effecting fluid flow of exhaust gas from the exhaust manifold to the intake manifold, and movable to a second position effecting fluid flow of charge air to the variable geometry turbine. | 5 |
REFERENCE TO RELATED APPLICATIONS
This application claims an invention which was disclosed in Provisional Application No. 61/180,615, filed on May 22, 2009, entitled “Interactive Visual Display Provisional Patent”. The benefit under 35 USC §119(e) of the United States provisional application is hereby claimed, and the aforementioned application is hereby incorporated herein by reference.
TECHNICAL FIELD OF THE INVENTION
The invention pertains to the field of information storage, enhancement, and analysis. More particularly, the invention pertains to a system and method for interactive visual representation, and the collection and enhancement of electronic files for analysis. A visualization tool is provided which allows for: entering and transferring a copy of an electronic file (uploading) into the system; enhancing data in the system; displaying the content of each file; and displaying an icon representation of each file along a timeline overlaid by tag labels. The tool provides for the visual arranging of tag labels, hiding of tags and content, and storing and recalling of such configuration settings.
BACKGROUND OF THE INVENTION
Traditionally, people, individuals or professionals have maintained diaries or maintained (paper) records to memorialize activities such as family events, business activities or transactions in general or around a particular issue. But as more records are digitally created and maintained, printing each action and maintaining printouts as paper files have become more challenging. As digital records can also be more easily manipulated with digital editing applications, printouts cannot be trusted anymore because such printouts may have been manipulated prior to printing. Digital records include, for example, email, chat or social media sessions, documents, spreadsheets or other files created by various software applications. Even records which traditionally have been analog are increasingly created digitally or can be converted to digital format: phone conversations are being transmitted using digital Internet protocols using Voice over Internet Protocol (VoIP); photos and videos are taken as digital pictures and motion files; music and voice mail are recorded as electronic files; video, chat, and audio streams can be stored as electronic files; and paper records can be scanned into digital images. Digital storage as an electronic file therefore provides a universal way to maintain records of any kind.
Archival of historic information may be useful in general to enable people to remember what they have been doing, and to enable people to share their experiences with others. In case of any type of dispute, records are often extremely important to resolve such dispute. Traditionally, paper records were sorted by date or organized into tabs or stacks of paper and enhanced with flags, sticky notes, highlighters, or notes on the margin or a separate piece of paper or separate documentation. Often none of this happened, and instead people just relied on the memory and knowledge of key individuals to understand the history of a particular transaction or relationship.
A need in the art therefore exists for a system and method that provides for storing any electronic file and for enhancing such files so that relevant files can be identified, displayed, analyzed, and shared.
DESCRIPTION OF RELATED ART
Online storage systems such as Flickr.com for pictures, Box.net for business documents or Youtube.com for video have made it easier to store and share digital data.
Sophisticated tools have been developed to gather references to digital information from multiple sources, and even to use automatic tools to understand some of the data and how one piece of information relates to another. Those tools may assist investigators by focusing on multi-dimensional representation of digital information through artificial intelligence analysis, but those tools require multiple annotation steps such as defining search terms, linking, and annotation on an item by item basis. Oculus Info Inc. has applied for several patents (U.S. Pat. No. 7,499,046, application Ser. Nos. 10/810,680, 11/289,381, 11/289,469, and 11/439,561) for such designs. However, the approach provided by these tools is too laborious for the maintenance of simple records for individuals or as part of people's usual business processes.
The legal profession also has developed sophisticated tools to gather digital evidence across an organization for analysis in a legal investigation. These tools are usually referred to as Electronic Data Discovery (EDD) tools. They allow for keyword searches, may provide automatic analysis of key concepts, may eliminate duplicate records, and may identify key individuals and how they interact (for example, through email). These tools might even show how many emails were sent over a time period (see Kodak U.S. Pat. No. 6,996,782). These tools are geared at after-the-fact analysis by professional investigators, but do not provide simple, ongoing, dynamic support for data enhancement and timeline visualization. These tools also focus on search and analysis of written information, but cannot handle unsearchable media files such as pictures, videos, and audio files.
In addition, general business tools (such as Microsoft Outlook) have used timeline displays to visualize historic information (see also Goldthwaite U.S. Pat. No. 7,146,574), but once there are more than a few dozen of items on the timeline, organizing and filtering of the relevant information becomes a challenge. When applied to written information, these general business tools can use textual analysis and search, but these tools also cannot handle unsearchable media files such as pictures, videos, and audio files.
SUMMARY OF THE INVENTION
The preferred embodiment of the present invention addresses the above-described problems of keeping track of digital information and analyzing such records by providing a computer system and method—a visualization tool—which provides data storage, enhancement, analysis, and sharing. The preferred embodiment will also be referred to as the digital diary system. Typically the data is collected and enhanced shortly after events happen or at least within a few days. But the data can also be collected and enhanced months or even years later. Preferably the system is implemented within a secure Internet Data Center (IDC) and accessible anywhere over the Internet from any personal computer (PC) or Internet-connected mobile device. To ensure data privacy and confidentiality, a new user of the system must create a separate account. If a user needs to access the data later, the user needs to log-in.
According to the preferred embodiment of the present invention, the system keeps track of data items, typically an electronic file and its associated meta data (i.e., any additional data which enhances the electronic file). Electronic files and therefore data items can be of various types: notes, word processing documents or emails (e.g., TXT, DOC, RTF, HTML, MSG files), digital paper images such as portable document format (PDF files), digital pictures (e.g., JPEG, BMP, PNG files), audio recordings such as voice mails (e.g., WAV, WMA or MP3 files), video files (e.g., MPEG4, Motion JPEG, WMV files), or any other type of electronic files. Paper documents and pictures can be photographed or scanned by a document scanner or copy machine and also uploaded. As digital cameras become more common and more mobile devices, such as smart phones and media players, include cameras, digital pictures can easily be taken to capture the surrounding circumstances of any activity (e.g., a meeting at a certain place or the signing of a document), and then uploaded.
According to the preferred embodiment of the present invention, these files need to be available on an Internet connected computer from where they can be uploaded into the digital diary system. The preferred embodiment also includes the ability to create electronic files such as text notes, audio recordings, or pictures directly and upload them into the digital diary system for storage. The digital diary system then records the date and time of the upload as the storage date and ensures that the uploaded electronic files cannot be later modified.
In an alternative embodiment of the present invention, a mobile device (e.g., Apple iPhone) with an Internet connection and with appropriate device-specific software implementation of the digital diary visual interface (or any subset of it) is used. Once such software is installed, such system can be used to create electronic files, log into the account, and upload created or existing electronic files. The software may also include the ability to upload device-specific data such as call logs (which may include: a phone number; type: incoming/outgoing/missed; date; and time) or Global Positioning System (GPS) information as an electronic file.
The technical advantages of the present invention are that: any type of data can be recorded; the digital diary system ensures only authorized users can access the data; the date and time when the data was uploaded is accurately recorded; and each uploaded electronic file cannot be manipulated after the upload. If the digital diary system is operated by a party independent from the events which are recorded, then in case of a dispute, the operating party can vouch for the integrity of the data. In contrast, traditional paper records cannot accommodate certain data (e.g., media files such as pictures, videos, and audio files), can be manipulated or altered, can be lost or destroyed, or can get into the possession of unintended persons. Even modern digital storage solutions, such as personal hard disks or traditional web-based email (e.g., Hotmail, Gmail or Yahoo) or storage systems (e.g., Box.net), allow for editing and deletion of files and may not adequately protect the privacy of the data.
According to the preferred embodiment of the present invention, once electronic files are uploaded to the digital diary system, the digital diary system allows the user through the data enhancement interface to enter and edit meta data of the uploaded electronic files. The user can add comments to any file. For example, a user may want to explain the circumstances of a particular picture, including who is shown in such a picture. The digital diary system automatically records the date and time each file was uploaded and will also attempt to extract the file creation date and Global Positioning System (GPS) information. The user also can enter the date and time of the event to which the file refers.
To organize the data into categories, the data enhancement interface also allows the user to associate each data item with any number of keywords called tags. Each such tag can represent an information category. To provide further grouping, the digital diary also provides special tags called folders. Each file can be associated with one or more folders. The digital diary system also provides statistics to the user on how much data enhancement has been done to encourage further data enhancement efforts, thereby improving later analysis.
Further technical advantages are realized by the digital diary system providing a timeline interface which allows the user to visually analyze the uploaded and enhanced data on a timeline and may allow identifying patterns. The timeline interface shows a full timeline representation on the top and a partial timeline representation on the bottom. Both timelines show data items as an icon and file name arranged by their event, creation, or storage date with earlier items to the left and later items to the right and earlier time of day towards the top and later times towards the bottom. If a long time has passed between the earliest and latest item and with a lot of items, the full timeline is very crowded. Therefore a partial timeline is shown on the bottom. The user can scroll through the partial timeline, zoom into a shorter time frame or zoom out to see a longer time frame. The time frame shown by the partial timeline is highlighted on the full timeline above. The user can click on any date on the full timeline to change the focus of the partial time line to the indicated date. The user can also click on any item to view its meta data, including a preview of its content, and download the file to review the content.
Overlaid onto the partial timeline are labels for each tag. The user can drag the tag label with a pointing device, such as a computer mouse, touchpad, or finger on a touch sensitive screen, to position the label to the user's liking within the area occupied by the partial timeline and its background. Each tag label has lines connecting the tag label to any item with which it is associated.
Once the user has set a certain timeline interface configuration by setting options such as filters, time frame and zoom level, tag label colors and placement, the user can name and save this configuration as a workspace so it can be recalled later.
Once such subset of items and tags is selected, the digital diary system's sharing interface can be used to print or download the items. An account owner can also choose to share the owner's data with an associate over the Internet.
BRIEF DESCRIPTION OF THE DRAWING
For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
FIG. 1A illustrates representative screen shots of the timeline interface of the preferred embodiment with a partial timeline on the bottom with items and tag labels and their connections.
FIG. 1B illustrates representative screen shots of the timeline interface of FIG. 1A with one tag label highlighted.
FIG. 1C illustrates representative screen shots of the timeline interface of FIG. 1B with an additional full timeline above.
FIG. 2 illustrates representative screen shots of the filter popup dialog of the time line interface of the preferred embodiment.
FIG. 3 illustrates representative screen shots of the data enhancement interface of the preferred embodiment.
FIG. 4 is a block diagram of a data processing system for a visualization tool in accordance with an embodiment.
FIG. 5 illustrates a flow diagram of the marshalling and visualization process of the present invention.
FIG. 6 illustrates a block diagram of a hardware implementation of a digital diary data processing system in accordance with an embodiment.
DETAILED DESCRIPTION OF THE INVENTION
The present invention, referred to as the digital diary system, allows an individual to store, enhance, analyze, and share data. The focus of the invention is the interactive visual representation of such data as it allows the user to visually analyze the uploaded and enhanced data on a timeline, and may allow the user to identify patterns, such as trends or behaviors.
Referring to FIG. 1A , there is a display area 1 (provided by the timeline interface 33 ) which displays data items such as 3 A and 3 C within a certain time frame along a partial timeline 4 over a background 69 . The partial timeline 4 is labeled with the month 5 B and date 5 A. Each data item is represented by an icon showing either a thumbnail preview, such as a picture 3 A or a yellow pad 3 C icon, or an icon specific to the file type in angled view and the file name of the item. If there are multiple items in close proximity (i.e., almost the same date/time), they are shown as stacked icons. If a user hovers a pointing device over a data item 3 A, the icon pops up and turns into full view and a popup window 3 B shows further data item details such as the file name (e.g., “harassment.jpg”), store and event date, and the number of comments and tags. Double-clicking on a data item shows further details, a preview of the content of the electronic file represented by the data item, and e.g. the ability to download the electronic file so its content can be displayed by an appropriate application.
Overlaid onto the partial timeline 4 are labels 2 for each tag (such as “harassment at work”, “picture from camera”, “drunk boss”). The user can drag the tag label 2 with a pointing device to position the label 2 to the user's liking within the area occupied by the partial timeline 4 and its background 69 . Each tag label has lines connecting the tag label 2 to any item 3 with which it is associated. The more items with which the tag is associated, the bigger (i.e., larger font size) the tag label 2 appears in comparison to less used tags. If the user double-clicks with a pointing device on the tag label 2 , a list of all data items pops up which are associated with this tag so that the user can further inspect the details of the files.
The user can also drag the partial timeline 4 to the right or left to show earlier or later data items 3 . The placement of the tag labels 2 does not change, but the lines connecting them with the data items are redrawn to reflect the new locations of the data items. As more data items show up, new lines are added and as data items drop off the visible time frame, lines are removed.
The user can drop an item 3 onto a tag label 2 to associate that item with that tag.
Referring to FIG. 1B , if a user hovers over a tag label 2 with a pointing device, all data items 3 D and lines associated with that tag are highlighted in the tag label color and lines are added in the direction of any additional associated off-screen data item (in this case four earlier items).
Referring to FIG. 1C , if the user clicks on the down arrow to the left of the tag label 2 , a tag drop down menu 60 appears and allows the user (1) to see the same data item popup as displayed when double-clicking on the tag label (see above), (2) to hide any other tag labels other than the selected one, (3) hide this tag, or (4) click on the color selection button 61 to rotate through a number of predefined colors to change the color of the tag label 2 to color-code the tag display.
FIG. 1C also shows at the top of the display area 1 an additional full timeline 6 A which is a small scale representation of the timeline showing all stored data items with the earliest item on the left and the latest item on the right whereas the portion 6 B representing the time frame shown by the partial timeline 4 is highlighted. The user can click anywhere on the full timeline 6 A to change the time frame of the partial timeline 4 or drag the highlighted portion 6 B to the left or right to move the displayed time frame to a later or earlier time.
Under the full timeline 6 A additional buttons are shown to manipulate the current timeline interface. The Zoom-In button 7 A reduces the time frame represented by the partial timeline 4 whereas the Zoom-Out button 7 B increases the time frame. With the button 8 the user can switch the order in which the data items are arranged on the timeline, which can be either the storage date or event date of the items. If the items are ordered by event date, the user can drag an item with a pointing device along the timeline to change the event date, but not any later than the storage date.
Clicking on the Filters button 74 brings up the filter popup window 70 shown in FIG. 2 which allows the user to filter the data items shown on the timeline to a subset of folders 71 , tags 72 , and file types 73 by checking the appropriate checkboxes. As the user selects a set of folders from the list 71 , the tag list 72 and file type list 73 is reduced to the tags and types included in the selected folders and again can be further reduced by the user by selecting the applicable tags and types. Alternatively tag labels can be hidden by direct manipulation of the tag label 2 as described above.
These many customization and filter settings allow the user to focus attention on certain information categories. Such information filtering can help the user to identify patterns of fraud or abuse for example.
Once the user has set a certain timeline interface configuration by setting options such as filters, time frame and zoom level, tag label colors and placement, the user can name and save this configuration as a workspace so it can be recalled later. Referring again to FIG. 1C , the Viewing Workspace button area 9 provides (from left to right) a way to load a named workspace by selecting such workspace from a drop down list, to save a workspace, to create a new workspace, and to delete an existing workspace.
Once such subset of items and tag labels is selected, the digital diary system's sharing interface 34 can be used to print the items either in summary (with information such as file name, tags, date/time) or even including the content of the file or including a visual representation of the timeline similar to the one provided by the timeline interface 33 . The items and tags can also be downloaded to a local hard disk, memory stick, or stored onto a compact disc. Optionally the downloaded files may include an application which provides standalone (i.e., without Internet) connection to the digital diary system, viewing of the same timeline interface as provided by the digital diary system, but without any editing capability.
To ensure data privacy and confidentiality, each new user of the digital diary system must create a separate account. The process of creating a separate account (1) entitles each new user to become the owner of that account and of its data, and (2) requires each new user to establish account credentials, such as user identification (userid) and password. The account owner gains access to the account, and the private and confidential data stored therein, by entering in the account user's unique credentials. Through the digital diary system's sharing interface 34 the account owner can also choose to share the owner's data with an associate over the Internet by entering the associate's email address and specifying a password. The account owner also can specify the type of access is granted to an associate, such as whether the associate can upload files, make comments, or just view the timeline and its items. The associate will then receive an email invitation with a link to the login page of the digital diary system. Once the associate enters the password the associate received through other means such as a phone call, the associate sees a similar timeline interface 33 as the account owner. Certain options may not be available to the associate based on what access was granted to the associate by the account owner. If the associate makes any comments or adds any tags, those are preceded by the associate's name so that the owner is alerted to the associate's contributions. For any activity by any associate, the owner also receives a daily email summary with a list of such activities.
Once a new account is created, electronic files need to be uploaded into the digital diary system through the item upload interface 31 . The preferred embodiment brings up a dialog to browse any files accessible on the user's computer so that the user can select which ones to upload. It also allows the user to create a note by entering a name and the note content on a yellow pad background and upload such electronic note file as a hyper text markup language (HTML) file to the digital diary system. Alternative embodiments may also provide methods for taking pictures or recording voice or video files and uploading them. Optionally such embodiments may prompt to enter a name, comment, or a series of tags to be associated with the data item. In any case the digital diary system automatically records the date and time each file was uploaded as the item's storage date and the system also attempts to extract the file creation date and GPS (Global Positioning System) location information.
In FIG. 3 , the picture shows a representative of the data enhancement interface 80 . A folder of data items can be selected from the folder list 81 (e.g. “Car Accident”), then to the right a data item list 82 is shown with a file type icon or a thumbnail preview of the content (a bigger version is shown in the preview area 84 below), such as a picture or yellow pad note, with the file name, stored and event date, size, and number of folder the item is contained in as well as the number of tags and comments. The checkbox on the left of each item allows a user to select multiple items for display and edit. A tag list 83 is shown on the bottom left. A user can drag with a pointing device a tag from that list and drop it onto the Add Tag field 86 for tagging data items selected from the item list 82 . Under the Tag field a Comment field 85 allows to add comments to the selected data items. The buttons in action area 87 allows a user to add the items to another folder or remove them from folders, download the associated files, edit the event date, digitally certify the files, or delete items. Tabs in the action area 87 also allow for displaying and editing all tags associated with the selected items, display, add, or delete comments, and display additional properties such as stored date and edit the event date statistics on how much data enhancement has been done. If the system identifies a low level of data enhancement (below a standard of usage set by a larger population of like users), it encourages further enhancement efforts to support meaningful analysis later.
In FIG. 5 , a flow diagram 200 of the preferred embodiment of the digital diary system is depicted. In the first step 201 , an electronic file is created for example by a digital camera or by the user entering a note. In order to access the digital diary's account, the user then needs to log in (step 202 ) by entering a valid userid and password. Only after proper authentication, at step 203 the user can upload the file and enhance the data (step 204 ) by for example associating tags, and entering dates and comments. Both step 203 and 204 can be repeated in any order. Once data has been uploaded and enhanced, the user can analyze the data visually in step 205 . The user may configure the visual display by filtering and arranging various aspects of the display and save such configuration as a workspace (step 206 ) so that it can be recalled at a later point in time (step 207 ). At step 208 the user may also share the configured and selected item by printing them, downloading them, or sharing them with other users over the Internet. Once the user is done, the user may log off (step 209 ).
This concludes the description of the visual interface 30 and its four components.
In FIG. 4 , the block diagram 100 describes the major components of the digital diary data processing system. The system is structured as an industry-standard three tier architecture: presentation layer is provided by the visual interface 30 , the business rules layer is provided by the diary server 20 , and the storage layer is provided by the account storage component 10 .
To ensure data privacy and confidentiality, a new user of the system must create a separate account. Any subsequent uploaded or created data is stored within that account. Each user of the digital diary system needs to create a userid and password (independent of accounts). Once a user is authenticated by providing the proper userid and password, the user gains access to the accounts whose account owners have granted the user some type of access to the owner's account. The userid and password and what account access is granted to each user is stored in the user access storage 15 . Once authenticated to access an account, the user can upload files which are stored in the file storage 11 . Each account maintains a list of tags which is stored in the tag storage 13 . A user can enhance the data, for example by adding comments and associating files with tags, and thereby creating meta data which is stored in the meta data storage 12 . Once the user starts analyzing the data, the user may also want to save a certain configuration of filters, tag labels, zoom levels etc. as a named workspace which is stored in the workspace storage 14 .
The diary server 20 provides a set of web services which take the input from the visual interface 30 , enforces any business rules, for example files can only be linked to existing tags and by authorized users, and stores the data in the account storage 10 or responds to requests from the visual interface 30 by retrieving the data from the account storage 10 , and returns them to visual interface component 30 for presentation.
The visual interface component 30 provides the user interface and its four components are described in detail above. The item upload interface 31 allows a user to upload digital data from various data sources 40 as electronic files to the digital diary system. Data sources may include the local hard disk, other systems which are connected to the user's PC, or portable media such as a USB drive or a memory card. The data enhancement interface 32 allows the user to enter meta data such as comments and associations of files with tags. The timeline interface 33 allows for display and analysis of all stored data items and they can be printed, downloaded, or shared over the Internet through the sharing interface 34 .
FIG. 6 illustrates one hardware implementation of the digital diary data processing system, and different implementation approaches are possible. The preferred implementation utilizes web client computers 301 to implement the visual interface 30 . The client computer is typically a laptop 301 B or desktop 301 A running a web browser such as Internet Explorer, Firefox, or Safari on an operating system such as Microsoft Windows, Apple Mac OS X, or Linux which connects to the digital diary Internet data center 320 over the Internet 310 . Alternatively the client computer could be a smart phone 301 C, TV, game console or any other computer with a web browser. The preferred implementation of the various visual interfaces uses a combination of HTML pages with JavaScript or Adobe Flash components which both access the web service interfaces of the application server 322 which implements the diary server 20 . Once the user connects to the web portal provided by the web server 321 , the HTML pages and Flash components are loaded from the web server 321 onto the client computing device 301 . Then the code embedded in the HTML pages and Flash components access the application server's web service interfaces and the diary server's software accesses the account storage component 10 running on the database server 323 to retrieve any necessary data.
Alternative implementations of the client may implement certain aspects or all of the visual interface 30 as a software component which is separately installed on the client computer and connects directly to the web services interfaces of the application server 322 . An alternative embodiment is an application for the Apple iPhone which is downloaded and installed from the Apple iTunes Application Store to the phone 301 C. The iPhone application implements the item upload 31 and certain aspects of the data enhancement interface 32 . Another alternative embodiment is an eUploader application implemented using Adobe Air technology so that it can be installed on various types of client computers 301 independent of their operating system. The eUploader's user interface implements the item upload interface component 31 by providing a drop area on the desktop. A user can utilize a pointing device to drag a file from various file places on the client computer and drop it onto the user interface of the eUploader application causing that file to be uploaded to the digital diary system by the eUploader application calling on the web services interfaces of the application server 322 .
Alternative implementations of the server components may implement the web, application, and database servers through multiple server each to increase scalability and fault tolerance. If a corporation is concerned about privacy, they may deploy a small system behind their firewall and use a single server instead of separate web, application, and database servers which simplifies the installation but may allow for a smaller number of concurrent users.
Accordingly, it is to be understood that the embodiments of the invention herein described are merely illustrative of the application of the principles of the invention. Reference herein to details of the illustrated embodiments is not intended to limit the scope of the claims, which themselves recite those features regarded as essential to the invention. | A system and method for data storage and data enhancement to facilitate the analysis of such data through a visual representation which depicts the data, its temporal aspects by aligning it along a timeline, and categorization of the data through tagging. The visual representation can be customized to analyze the data in various ways to identify potential patterns and share it with others. | 6 |
FIELD OF THE INVENTION
[0001] This invention relates to a means of preparing a sealant fluid for use in turbomachinery as a barrier or buffer fluid from gas to liquid (GTL) or coal to liquid based feed formulations, such as Fischer-Tropsch wax.
BACKGROUND OF THE INVENTION
[0002] Sealant fluids, more specifically barrier fluids and buffer fluids are the external fluids that are used in wet seals to prevent leakage of process fluids to the environment. They are used in devices such as pumps, compressors, and other types of turbomachinery in which the pressure of the process fluid is increased. A barrier fluid may also be used as a buffer fluid. A barrier fluid may be maintained at a pressure that is higher than that of the process fluid, while a buffer fluid is maintained at a pressure that is the same as or lower than that of the process fluid. The pressure employed is dependent upon the types of seals used in the machinery.
[0003] There are several purposes for using a sealant fluid, including:
[0000] (a) insulating a hazardous process fluid which should not be released to the environment;
(b) minimizing pollution problems;
(c) minimizing leaks and waste of an expensive product; and
(d) minimizing unscheduled down time.
[0004] A sealant fluid should be:
[0000] (a) compatible with the process being performed by the machinery;
(b) compatible with the seal materials;
(c) a good lubricant and heat transfer medium for the seal faces; and
(d) benign to the environment and to workers.
[0005] Sealant fluids are generally selected from the group comprising mineral oils, polyalpha olefins (PAO's), kerosene or diesel, glycols, alcohols and water. PAO based sealant fluids provide excellent performance over mineral oil diesels in terms of oxidative stability, high temperature performance and low temperature performance PAO based fluid is expensive, however. GTL based formulations have been developed that provide excellent performance at reduced costs. The GTL and CTL based formulations possess high viscosity index and low pour point, and are made using high quality base oil (see Table 1) that will soon become readily available at prices competitive to conventional Group II and Group III base oils.
BRIEF DESCRIPTION OF THE INVENTIONS
[0006] Two fluid formations suitable for use as sealant fluids in turbomachinery were developed using GTL XXL and GTL XL (see Table 1) as lubricants which were blended with additives as shown in Table 2. The performance of these products was evaluated against sealant fluid derived from polyalphaolefins (Table 2). It was found that GTL and CTL based formulations can provide comparable performance Typically PAO based sealant fluid cost is high. GTL and CTL based sealant fluids can provide excellent performance properties similar to those provided by PAO based fluids but at lower costs.
[0007] This application discloses a fluid, suitable for use in turbomachinery as a sealant fluid. It comprises: a lubricant base oil having an average molecular weight greater than 320, a viscosity index greater than 118, and a weight percent paraffinic carbons greater than 97%. The sealant fluid of this invention has a pour point of less than −60° C. and a sequence II foam tendency by ASTM D 892-03 of less than 30 ml.
[0008] We have invented a process for making a sealant fluid with very low pour point and improved foam tendencies. The process comprises the steps of a) selecting a waxy feed having greater than 75 wt % n-paraffins and less than 25 ppm total combined nitrogen and sulfur; b) hydroisomerization dewaxing the waxy feed to produce a lubricant base oil; c) fractionating the lubricant base oil into one or more fractions; d) selecting one or more of the fractions having an average molecular weight greater than 320, a viscosity index greater than 118, a weight percent olefins less than 25; and e) blending the one or more selected fractions with oil additives. The sealant fluid has a pour point of less than −60C, a Viscosity Index of at least 129, and a sequence II foam tendency by ASTM D 892-03 of less than 30 ml.
BRIEF DESCRIPTION OF THE DRAWING
[0009] The FIGURE illustrates the manner in which barrier fluid is added to a pump and its use in preventing leakage of fluid being pumped.
DETAILED DESCRIPTION
[0010] The test methods and terminology used throughout this specification are conventional and understood by those of ordinary skill in the lubricating arts. A few are briefly mentioned in the following paragraphs.
[0011] Noack volatility is defined as the mass of oil, expressed in weight %, which is lost when the oil is heated at 250° C. with a constant flow of air drawn through it for 60 min., measured according to ASTM D5800-05, Procedure B.
[0012] “Molecules with cycloparaffinic functionality” mean any molecule that is, or contains as one or more substituents, a monocyclic or a fused multicyclic saturated hydrocarbon group.
[0013] Molecules with monocycloparaffinic functionality” mean any molecule that is a monocyclic saturated hydrocarbon group of three to seven ring carbons or any molecule that is substituted with a single monocyclic saturated hydrocarbon group of three to seven ring carbons.
[0014] “Molecules with multicycloparaffinic functionality” mean any molecule that is a fused multicyclic saturated hydrocarbon ring group of two or more fused rings, any molecule that is substituted with one or more fused multicyclic saturated hydrocarbon ring groups of two or more fused rings, or any molecule that is substituted with more than one monocyclic saturated hydrocarbon group of three to seven ring carbons.
[0015] Molecules with cycloparaffinic functionality, molecules with monocycloparaffinic functionality, and molecules with multicycloparaffinic functionality are reported as weight percent and are determined by a combination of Field Ionization Mass Spectroscopy (FIMS), HPLC-UV for aromatics, and Proton NMR for olefins.
[0016] Oxidator BN measures the response of lubricating oil in a simulated application. High values, or long times to adsorb one liter of oxygen, indicate good stability. Oxidator BN can be measured via a Dornte-type oxygen absorption apparatus (R. W. Dornte “Oxidation of White Oils,” Industrial and Engineering Chemistry, Vol. 28, page 26, 1936), under 1 atmosphere of pure oxygen at 340° F., time to absorb 1000 ml of O 2 by 100 g. of oil is reported. In the Oxidator BN test, 0.8 ml of catalyst is used per 100 grams of oil. The catalyst is a mixture of soluble metal-naphthenates simulating the average metal analysis of used crankcase oil. The additive package is 80 millimoles of zinc bispolypropylenephenyldithiophosphate per 100 grams of oil.
[0017] Molecular characterizations can be performed by methods known in the art, including Field Ionization Mass Spectroscopy (FIMS) and n-d-M analysis (ASTM D 3238-95 (Re-approved 2005) with normalization). In FIMS, the base oil is characterized as alkanes and molecules with different numbers of unsaturations. The molecules with different numbers of unsaturations may be comprised of cycloparaffins, olefins, and aromatics. If aromatics are present in significant amount, they are identified as 4-unsaturations. When olefins are present in significant amounts, they are identified as 1-unsaturations. The total of the 1-unsaturations, 2-unsaturations, 3-unsaturations, 4-unsaturations, 5-unsaturations, and 6-unsaturations from the FIMS analysis, minus the wt % olefins by proton NMR, and minus the wt % aromatics by HPLC-UV is the total weight percent of molecules with cycloparaffinic functionality. If the aromatics content was not measured, it was assumed to be less than 0.1 wt % and not included in the calculation for total weight percent of molecules with cycloparaffinic functionality. The total weight percent of molecules with cycloparaffinic functionality is the sum of the weight percent of molecules with monocyclopraffinic functionality and the weight percent of molecules with multicycloparaffinic functionality.
[0018] Molecular weights are determined by ASTM D2503-92(Reapproved 2007). The method uses thermoelectric measurement of vapor pressure (VPO). In circumstances where there is insufficient sample volume, an alternative method of ASTM D2502-04 may be used; and where this has been used it is indicated.
[0019] Volatile organic content (VOC) is measured by ASTM D 2369-07. A low value is preferred. Cleveland Open Cup (COC) flash point is measured by ASTM D 92-05.
[0020] Pour point is measured by ASTM D5950-02 (Reapproved 2007), using an automatic tilt method.
[0021] The aniline point test indicates if an oil is likely to swell or shrink the elastomers (rubber compounds) that come in contact with the oil. The aniline point is called the “aniline point temperature,” which is the lowest temperature (° F. or ° C.) at which equal volumes of aniline (C6H5NH2) and the oil form a single phase. The aniline point (AP) is an indicator of the amount of aromatic hydrocarbons in an oil sample. A low AP is indicative of higher aromatics, while a high AP is indicative of lower aromatics content. The aniline point is determined by ASTM D611-07. In some embodiments, lubricant base oil fractions derived from highly paraffinic wax, such as Fischer-Tropsch waxes, have a relatively low aniline point. This can be attributed to the lubricant base oil having a high ratio of molecules with monocycloparraffinic functionality to molecules with multicycloparaffinic functionality. Accordingly, the lubricant base oil fractions derived from highly paraffinic wax with low aniline points exhibit good elastomer compatibility.
[0022] The Four Ball Wear Test which measures antiwear properties is set forth in ASTM D-4172-94(Reapproved 2004) (4-ball wear). The testing is done on a Falex Variable Drive Four-Ball Wear Test Machine. Four balls are arranged in an equilateral tetrahedron. The lower three balls are clamped securely in a test cup filled with lubricant and the upper ball is held by a chuck that is motor-driven. The upper ball rotates against the fixed lower balls. Load is applied in an upward direction through a weight/lever arm system. Loading is through a continuously variable pneumatic loading system. Heaters allow operation at elevated oil temperatures. The three stationary steel balls are immersed in 10 milliliters of sample to be tested, and the fourth steel ball is rotated on top of the three stationary balls in “point-to-point contact.” The machine is operated for one hour at 75° C. with a load of 20 kilograms and a rotational speed of 1800 revolutions per minute. The lubricating oils tested generally contain all the additives typically found in an industrial oil.
[0023] Feeds used to prepare the lubricant base oil according to the process of the invention are waxy feeds containing greater than 75 weight percent normal paraffins, preferably at least 85 weight percent normal paraffins, and most preferably at least 90 weight percent normal paraffins. The waxy feed may be a conventional petroleum derived feed, such as, for example, slack wax, or it may be derived from a synthetic feed, such as, for example, a feed prepared from a Fischer-Tropsch synthesis. A major portion of the feed should boil above 650° F. Preferably, at least 80 weight percent of the feed will boil above 650° F., and most preferably at least 90 weight percent will boil above 650° F. Highly paraffinic feeds used in carrying out the invention typically will have an initial pour point above 0° C., more usually above 10° C.
[0024] Slack wax can be obtained from conventional petroleum derived feedstocks by either hydrocracking or by solvent refining of the lube oil fraction. Typically, slack wax is recovered from solvent dewaxing feedstocks prepared by one of these processes. Hydrocracking is usually preferred because hydrocracking will also reduce the nitrogen content to a low value. With slack wax derived from solvent refined oils, deoiling may be used to reduce the nitrogen content. Hydrotreating of the slack wax can be used to lower the nitrogen and sulfur content. Slack waxes possess a very high viscosity index, normally in the range of from about 140 to 200, depending on the oil content and the starting material from which the slack wax was prepared. Therefore, slack waxes are suitable for the preparation of lubricant base oils having a very high viscosity index.
[0025] The waxy feed useful in this invention has less than 25 ppm total combined nitrogen and sulfur. Nitrogen is measured by melting the waxy feed prior to oxidative combustion and chemiluminescence detection by ASTM D 4629-96. The test method is further described in U.S. Pat. No. 6,503,956, incorporated by reference herein. Sulfur is measured by melting the waxy feed prior to ultraviolet fluorescence by ASTM D 5453-00. The test method is further described in U.S. Pat. No. 6,503,956, incorporated by reference herein.
[0026] Waxy feeds useful in this invention are expected to be plentiful and relatively cost competitive in the near future as large-scale Fischer-Tropsch synthesis processes come into production. The waxy feeds may be produced from any synthesis gas, such as those made in a GTL or a CTL process, using a Fischer-Tropsch process. Synthesis gas fed to the Fischer-Tropsch process may be produced from a broad range of hydrocarbons, including waste plastic or other polymers, biomass, cellulose, vegetation, agricultural waste, waste paper or cardboard, wood, natural gas, shale or coal. Syncrude prepared from the Fischer-Tropsch process comprises a mixture of various solid, liquid, and gaseous hydrocarbons. Those Fischer-Tropsch products which boil within the range of lubricant base oil contain a high proportion of wax which makes them ideal candidates for processing into lubricant base oil. Accordingly, Fischer-Tropsch wax represents an excellent feed for preparing high quality lubricant base oils according to the process of the invention. Fischer-Tropsch wax is normally solid at room temperature and, consequently, displays poor low temperature properties, such as pour point and cloud point. However, following hydroisomerization of the wax, Fischer-Tropsch derived lubricant base oils having excellent low temperature properties may be prepared. A general description of the hydroisomerization dewaxing process may be found in U.S. Pat. Nos. 5,135,638 and 5,282,958; and U.S. patent application 20050133409.
[0027] The hydroisomerization is achieved by contacting the waxy feed with a hydroisomerization catalyst in an isomerization zone under hydroisomerizing conditions. In one embodiment, the hydroisomerization catalyst preferably comprises a shape selective intermediate pore size molecular sieve, a noble metal hydrogenation component, and a refractory oxide support. In one embodiment, the shape selective intermediate pore size molecular sieve is preferably selected from the group consisting of SAPO-11, SAPO-31, SAPO-41, SM-3, ZSM-22, ZSM-23, ZSM-35, ZSM-48, ZSM-57, SSZ-32, offretite, ferrierite, and combinations thereof SAPO-11, SM-3, SSZ-32, ZSM-23, and combinations thereof are more sometimes more preferred. In one embodiment the noble metal hydrogenation component is platinum, palladium, or combinations thereof.
[0028] The hydroisomerizing conditions depend on the waxy feed used, the hydroisomerization catalyst used, whether or not the catalyst is sulfided, the desired yield, and the desired properties of the lubricant base oil. In one embodiment, the hydroisomerizing conditions include temperatures of 260° C. to about 413° C. (500 to about 775° F.), a total pressure of 15 to 3000 psig, and a hydrogen to feed ratio from about 0.5 to 30 MSCF/bbl, or from about 1 to about 10 MSCF/bbl. In some embodiments, hydrogen will be separated from the product and recycled to the isomerization zone.
[0029] In one embodiment, the hydroisomerization conditions are tailored to produce one or more fractions having greater than 5 weight percent molecules with monocycloparaffinic functionality, or having greater than 10 weight percent molecules with monocycloparaffinic functionality. In one embodiment the fractions will have a viscosity index greater than 140 and a pour point less than zero° C. In some embodiments, the pour point will be less than −10° C.
[0030] Optionally, the lubricant base oil produced by hydroisomerization dewaxing may be hydrofinished. The hydrofinishing may occur in one or more steps, either before or after fractionating of the lubricant base oil into one or more fractions. The hydrofinishing is intended to improve the oxidation stability, UV stability, and appearance of the product by removing aromatics, olefins, color bodies, and solvents. A general description of hydrofinishing may be found in U.S. Pat. Nos. 3,852,207 and 4,673,487, incorporated herein. The hydrofinishing step may be needed to reduce the weight percent olefins in the lubricant base oil to less than 10, preferably less than 5, more preferably less than 1, and most preferably less than 0.5. The hydrofinishing step may also be needed to reduce the weight percent aromatics to less than 0.3, preferably less than 0.06, more preferably less than 0.02, and most preferably less than 0.01.
[0031] In one embodiment the hydroisomerizing and hydrofinishing conditions in the process of this invention are tailored to produce one or more selected fractions of lubricant base oil having less than 0.06 weight percent aromatics, less than 5 weight percent olefins, and greater than 5 weight percent molecules with cycloparaffinic functionality.
[0032] The lubricant base oil fractions, in one embodiment, have a very high viscosity index, generally greater than 118, but they may also have an even higher viscosity index, such as greater than an amount calculated by the equation: Viscosity Index=28*Ln(Kinematic Viscosity at 100° C., in cSt)+95; wherein Ln refers to the natural logarithm to the base ‘e’. Viscosity index is determined by ASTM D 2270-04.
[0033] The lubricant base oil fractions have measurable quantities of unsaturated molecules measured by FIMS (Field Ionization Mass Spectroscopy). In one embodiment they have greater than 5 weight percent molecules with monocycloparaffinic functionality, in another embodiment they have greater than 10. In one embodiment they have a ratio of weight percent molecules with monocycloparaffin functionality to weight percent molecules with multicycloparaffinic functionality greater than 2.1, greater than 6, greater than 15, greater than 40 or greater than 100. The presence of predominantly molecules with monocycloparaffinic functionality in the lubricant base oil fractions provides excellent oxidation stability as well as desired additive solubility and elastomer compatibility. In one embodiment the lubricant base oil fractions have a weight percent olefins less than 10, less than 5, less than 1, or less than 0.5. The lubricant base oil fractions have a weight percent aromatics less than 0.3, less than 0.06, or less than 0.02.
[0034] In one embodiment the lubricant base oil fractions have low levels of alkyl branches per 100 carbons, such as less than 8 alkyl branches per 100 carbons, or less than 7. The branches are alkyl branches and in one embodiment they are predominantly methyl branches (—CH3). In addition, the alkyl branches can be positioned over various branch carbon resonances by carbon-13 NMR. The low levels of predominantly methyl branches impart high viscosity index and good biodegradability to the lubricating base oils, and sealant oils made from them.
[0035] In one embodiment the lubricant base oil fractions of this invention will have T90-T10 boiling point distributions less than 180 degrees F., such as between 50 degrees F. and less than 180 degrees F., or between 90 and less than 150 degrees F.
[0036] In some embodiments, where the olefin and aromatics contents are significantly low in the lubricant base oil fraction of the sealant fluid, the Oxidator BN of the lubricant base oil will be greater than 25 hours, preferably greater than 35 hours, more preferably greater than 40 hours. Oxidator BN is a convenient way to measure the oxidation stability of lubricating base oils. The Oxidator BN test is described by Stangeland et al. in U.S. Pat. No. 3,852,207. The Oxidator BN test measures the resistance to oxidation by means of a Dornte-type oxygen absorption apparatus. See R. W. Dornte “Oxidation of White Oils,” Industrial and Engineering Chemistry, Vol. 28, page 26, 1936. Normally, the conditions are one atmosphere of pure oxygen at 340° F. The results are reported in hours to absorb 1000 ml of O 2 by 100 g. of oil. In the Oxidator BN test, 0.8 ml of catalyst is used per 100 grams of oil and an additive package is included in the oil. The catalyst is a mixture of soluble metal naphthenates in kerosene. The mixture of soluble metal naphthenates simulates the average metal analysis of used crankcase oil. The level of metals in the catalyst is as follows: Copper=6,927 ppm; Iron=4,083 ppm; Lead=80,208 ppm; Manganese=350 ppm; Tin=3565 ppm. The additive package is 80 millimoles of zinc bispolypropylenephenyldithio-phosphate per 100 grams of oil, or approximately 1.1 grams of
[0037] OLOA 260. The Oxidator BN test measures the response of lubricating base oil in a simulated application.
[0038] High values, or long times to consume one liter of oxygen, indicate good oxidation stability. Traditionally it is considered that the Oxidator BN should be above 7 hours, but the Oxidator BN of the lubricant base oil fractions of this invention are preferably much higher.
[0039] OLOA is an acronym for Oronite Lubricating Oil Additive[R], which is a registered trademark of Chevron Oronite.
EXAMPLES
Example 1
[0040] Sample of hydrotreated Fischer-Tropsch wax made using a Fe-based Fischer-Tropsch catalyst was analyzed and found to have the properties as shown in Table I.
[0041] The Fischer-Tropsch wax was hydroisomerized over a Pt/SAPO-11 catalyst with an alumina binder. Operating conditions included temperatures between 625° F. and 695° F. (329° C. and 399° C.), LHSV of 0.6 to 1.0 hr−1, reactor pressure of 300-400 psig, and once-through hydrogen rates of between 4 and 6 MSCF/bbl. The reactor effluent passed directly to a second reactor containing a Pt/Pd on silica-alumina hydrofinishing catalyst operated at 1000 psig. Conditions in the second reactor included a temperature of about 450° F. (232° C.) a LHSV of 1.0 hr−1, and a once-through hydrogen flow rate of between 5 and 7 MSCF/bbl.
[0042] The products boiling above 650° F. were fractionated by vacuum distillation to produce distillate fractions of different viscosity grades, as shown in Table 1, below.
[0000]
TABLE 1
Classification
XXL
XL
Kinematic Viscosity @ 40° C., cSt
6.31
11.16
Kinematic Viscosity @ 100° C. cSt
2.032
2.988
Viscosity Index
118
125
Cold Crank Viscosity @ −40° C., cP
975
1.525
Pour Point, ° C.
−57
−36
n-d-m
Molecular Weight, gm/mol
320
375
(VPO)
Density, gm/ml
0.7956
0.8059
Refractive Index
1.4453
1.4507
Paraffinic Carbon, %
97.82
96.97
Naphthenic Carbon, %
2.18
3.03
Aromatic Carbon, %
0.00
0.00
Carbon, Wt. %
85.14
85.23
Hydrogen, Wt. %
14.86
14.77
Oxidator BN, hrs
42.82
35.9
ANTEK SULFUR
<1
<2
LOW LEVEL NITROGEN
<0.1
<0.1
Noack, wt. %
81.9
26.8
HPLC-UV (LUBES)
Aromatics Total
0.00226
0.00261
COC Flash Point, ° C.
168
206
SIMDIST TBP (WT %), F.
TBP @0.5
534
679
TBP @5
588
701
TBP @10
604
709
TBP @20
625
720
TBP @30
640
728
TBP @40
652
735
TBP @50
663
741
TBP @60
672
748
TBP @70
682
756
TBP @80
692
764
TBP @90
702
774
TBP @95
709
782
TBP @99.5
724
802
FIMS
Alkanes
85.4
75.3
1-Unsaturation
13.6
23.2
2-Unsaturation
0.5
1.1
3-Unsaturation
0.2
0.2
4-Unsaturation
0.1
0
5-Unsaturation
0.2
0
6-Unsaturation
0
0.2
Example 2
[0043] The Fischer-Tropsch derived lubricant base oils prepared above and depicted in Table 1 were blended with additives comprising antioxidant, antiwear, foam inhibitor, pour point depressant and metal deactivators, resulting in the sealant fluids of this invention, which are depicted in columns 2 and 3 of Table 2.
[0000]
TABLE 2
Barrier Fluid Comparison
Royal Purple
Barrier Fluid
IND
Barrier Fluid A
Barrier Fluid B
Barrier Fluid C
GT22
CHEVRON SYNFLUID (R), 4 CST
99.3475
GTL Fluid-XXL
94.24
GTL Fluid-XL
94.24
Polyol Ester
5.00
5.00
Amine Phosphate
0.2000
0.20
0.20
Combination of Phenolic and aminic
0.2000
0.20
0.20
antioxidant
Tolutriazol
0.0500
0.05
0.05
Acrylic Defoamer
0.0025
Triphenyl phosphorothionate
0.2000
.20
.20
Silicone based Foam Inhibitor
0.01
0.01
Pour point depressant
0.10
0.10
Properties to Test:
API Gravity
41.1
43.9
41.8
Saybolt Color
+30
+30
+30
Appearance
1
1
1
Vis at 40 C.
16.92
6.615
11.37
5
Vis at 100 C.
3.889
2.127
3.065
1.9
VI
125
129
132
Flash Pt, C. (F.)
218
166
202
168.3
Pour Point, C. (F.)
<−63
<−63
<−60
−56.7
Foam, Seq, I, II and III
Seq I (FT)
0
0
0
Seq I (FS)
0
0
0
Seq II (FT)
0
30
0
Seq II (FS)
0
0
0
Seq III (FT)
0
0
0
Seq III (FS)
0
0
0
PDSC, Induction Temp ° C., 100/min;
220
213
219
200 psi O2
Four Ball Wear (1800 rpm,
0.316
0.491/.382*
0.329
20 k, 75 C., 1 hr), mm scar dia
VOC content, D2369, gm/lit
4.6
118
15
Aniline Point, F.
246.7
216.8
231.1
[0044] Barrier Fluid A is a PAO based sealant fluid which contains an antiwear, antioxidant, metal deactivator and a defoamer. The PAO sealant fluid does not contain foam inhibitor or a pour point depressant. Barrier Fluids B and C are GTL based barrier fluids. Royal Purple is a commercial synthetic PAO based sealant fluid.
[0045] Overall GTL based sealant fluid will be significantly less expensive than the PAO based sealant fluid while providing comparable performance. | It has been determined that sealant fluid formulations comprising a lubricant oil derived from Fischer-Tropsch waxes demonstrate performance comparable to sealant fluid comprising lubricants derived from polyalphaolefins (PAO's). The sealant fluids of the current invention can provide excellent performance properties similar to those provided by PAO based sealant fluids, but at lower cost. | 2 |
REFERENCE TO RELATED PATENT APPLICATIONS
The present patent application is one of three patent applications by the same inventor filed on an even date and assigned to the same assignee. The present U.S. Pat. application for DECOMPRESSING RUN-LENGTH-ENCODED TO TRANSITION-ENCODED FONT IMAGE INFORMATION IN AN IMAGE GENERATOR teaches the use of conventional, run-length-encoded, font image information to generate, by a process called decompression, a corresponding new type of information called transition-encoded information. This transition-encoded information represents every black-to-white, and every white-to-black, transition, and the pixel locations of each of these transition, which are undergone by selective pixels upon a single scan line. A font image is generated as the synthesis product of many successive scan lines.
Companion U.S. Pat. application Ser. No. 096,960, for IMAGE GENERATION FROM TRANSITION-ENCODED FONT INFORMATION teaches the use of this particular new type of information--which information regards the transitions, and the pixel locations of transitions, from both white to black, and from black to white, which are undergone along and upon a scan line--in order to generate a font image.
Finally, companion U.S. Pat. application Ser. No. 096,959 for COMBINATION OF TRANSITION-ENCODED FONT INFORMATION FOR GENERATION OF SUPERIMPOSED FONT IMAGES teaches a manner of combining transition-encoded information in order to simultaneously image a plurality of superimposed font images. It is especially taught how to combine transition-encoded information for certain pixel points at which both transition-encoded font images simultaneously indicate a white to black (or a black to white) transition.
The three related patent applications are collectively concerned with the generation, use, and special combining for use, of a particular new form of encoding image information--transition-encoded font image information--in and by an image generator device, nominally a printer. The contents of the aforementioned companion patent applications are incorporated herein by reference.
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention generally relates to image generation hardware, particularly including printers and most particularly including non-impact printers. The present invention is concerned with a generation of a particular new form of encoded information--transition-encoded font image information--which is used in the generation of a font image. The manner by which this new information is so used for font image generation will be explained somewhat simplistically in the present specification. A more sophisticated teaching of the preferred manner of image generation transpiring from the selfsame identical transition-encoded font image information is particularly taught in each of the companion patent applications. However, for purposes of understanding the present invention it is only necessary to simplistically understand the use of transition-encoded information in the generation of images.
The present invention is particularly concerned with what, exactly, this new form "transition-encoded" information is, and how it is derived. It will be shown that the new form "transition-encoded" information is derived by transforming, in and by a new process called "decompression", certain conventional run-length-encoded font image information. Both the run-length-encoded information which is "decompressed", and the "transition-encoded" information into which it is "decompressed", represent the images of characters and of character fonts which are generatable by an image generator. The reason that the transformation, or "decompression", which is the subject of the present invention and of this disclosure is performed is because run-length-encoded information is not directly usable to control the marker of an image generator, whereas this new form transition-encoded font information into which the run-length-encoded information is efficiently transformed will be shown to be highly effective for controlling the marker, in real time, to actually generate the image of a particularly chosen character at a particularly chosen font.
Description of the Prior Art
An image generator is a device which receives information, nominally in ASCII form, from a computer, a computer terminal, or other such device. The image generator interprets such information in order to effect a pixel by pixel monochrome or color control of a marking device. For example, an image generator may be within a printer. For example, the pixel by pixel monochrome control may be effected by an on/off control of a raster-scanned marking device such as a laser light beam.
During the course of image generation, the image generator, nominally a printer, needs to, and will, transform, or "decompress", certain high-level encoding, such as the ASCII encoding, representing the characters and the character fonts to be imaged (printed), into the more detailed notational encodings which represent the actual font images of each character to be printed. The actual font image information may be represented by bit map (raster scan) data, run length encoded raster scan data, or by outline format (similar to pen plotter format) data. These detailed encodings are the information which is actually used, in real time, to control the marking device of the image generator. For example, a certain single ASCII encoding always represents an "a". The image generator will transform this ASCII "a" into an image represented in a certain font; for example, block "a" or an italic "a" or an inverse color "a" or literally thousands of particular ways of generating the font image of an "a" (all of which font images are recognizable to the human brain as an "a"). Each of these different images, although all are "a", has an associated detail encoding, unique from all other detail encodings.
A commonly used prior art form of such detailed encodings is bit-map encoding. A grid matrix of the image area is created. Within this grid area the presence, or absence, of a marking at each intersection of the grid in a formation of an image of a particular character of a particular font is represented by the presence, or absence, of a binary bit within a data store, or map, for that particular character and font.
The transformation, or decompression, of information encodings involved in bit-mapped image generation normally transpires as follows. When the device controlling an image generation inputs a character, for example, the ASCII encoded letter "a", then the image generator determines from internally stored information what some particular certain image of an "a" looks like in some particular font. Usually there is a pixel map stored in the image generator memory which "maps out" those pixels for which the marking device will be caused to be "on" and those for which it will be caused to be "off" during the generation of a particular font image for a particular character, thereby generating the desired white and black image of the character. The user normally additionally specifies a font type, font size, and various other information in order to select amongst many alternative ways of representing the same character, for example the small letter "a" as printed in many fonts (Roman, Italic, etc.) at many sizes, slants, boldness levels, etc.
Depending on the resolution, a substantial amount of memory space can be tied up in the bit mapped specification of each font. For example, if the resolution is 300×300 dots (or pixels) per inch (dpi), then a 12 point character (1/6" high) requires 1500 bits (30×50) of information. If the resolution is 1200×1200 dpi, then 24K bits of information are required. For one complete font alphabet of 128 characters, over 3 megabits of information are required for the bit-mapped image representations of these 128 characters. Typically it is desired to have many fonts available simultaneously. The present industry trend is towards higher resolution and more fonts. This often results in memory requirements which are difficult, if not totally impractical. Some prior art image generation systems use hard discs for bit-mapped font image information storage. However, these systems run slower than certain prior art systems which store bit-mapped font image information in semiconductor random access memory (RAM) because of the longer access time of disk memory as compared to semiconductor RAM.
It is also known in the prior art to store font image information either in Programmable Read Only Memory (PROM), or on a disk, in a compressed mode. However, this compressed font image information is always fully "blown up" into full bit-mapped data in RAM. This bit-mapped information means that one bit of storage is required for each pixel of information on the page. In some image generators, the page to be printed is assembled on a pixel by pixel basis before it is printed. This is referred to as a "full bit map" system. It is quite flexible, but the cost is high.
A second problem with bit-mapped image generation systems occurs because of the trend towards higher densities and more fonts. It is currently desired to place characters at any position within an image area (on the page)--including in overlapped positions--without regard to where any other character might be placed. One way of doing this is to have a very fast and very capable microprocessor system place the information for each character in a large RAM. However, this adversely takes a lot of processing time while the printer engine sits idle and while the programmer sits impatiently as this information is being assembled.
The present invention generally deals with the transformation, or decompression, of a particular type of font information, called run-length-encoded font information, upon all such times as a font is directed to be imaged, or printed. Run-length-encoding of information regarding visual images, including the visual images of fonts, is known in the prior art. Run-length-encoded information is simply a recording of the number of pixel elements which are between each transition from white to black, or from black to white, within a single horizontal "scan" line, one of many scan lines which in composite make up the font image. This one type of run-length-encoded font information was, theretofore the present invention, decompressed into bit-mapped font image information.
The present invention will instead decompress run-length-encoded font image information into a new type of information, without direct correspondence in the prior art, which will be called transition-encoded font image information. The transition-encoded font image information will control the pixel by pixel generation of each scan line within a font image equivalently as the prior art bit-mapped font image information did alternatively control such pixels to generate the scan lines and the font image.
SUMMARY OF THE INVENTION
1. The Environment of the Present Invention, and its Relationship to Certain Other Inventions Within Related Patent Applications
The present invention is embodied in an image generating system, nominally a printer, which uses a particular new format of information in the generation of a visually discernible font image. This new format of information useful in image generation is called transition-encoded information. It is derived by a transformation, or decompression, of run-length-encoded information concerning font images.
The image generating system in accordance with the present invention is conventionally commanded by a computer or the like. The system is commanded as to which particular character at which particular font (at which particular size, slant, density, etc.) should have its associated run-length-encoded font image information decompressed in order that, responsively to this decompressed information, the image generator should generate the appropriate font image of the appropriate character. The image generating system is also commanded as to where within the image area the font character image should be placed.
When so directed to generate a particular one of large number of characters at a particular one of a large number of fonts, the image generating system in accordance with the present invention will decompress certain appropriate run-length-encoded information in order to produce, at one time, only so much transition-encoded information as controls the generation of one scan line. Subsequent decompressions of still further run-length-encoded information will permit the generation of subsequent scan lines, and will ultimately permit the generation of the entire font image. Thus the transition-encoded font information is transitory within the ongoing operation of the image generating system of the present invention. Therefore, it might alternatively be considered that the present invention is a system for the real-time generation of raster scanned images immediately, but indirectly, from run-length-encoded information without the necessity of forming bit maps (from any information source). Instead of these bit maps, the marker of the image generating system will be controlled in generation of the image by an intermediary form of information called transition-encoded information.
2. Summary of a First Related Invention Usefully Understood for Understanding the Present Invention
The present invention concerns what transition-encoded information is, and how it is derived. The motivation as to why such information should be derived is partially visible in the present specification, but some advantages of use of transition-encoded font information are most apparent in the previously-identified related patent applications. Suspending for the moment the subject of the present invention as to how transition-encoded font information is derived, a summary of a first related patent application regarding a use of transition-encoded information is given in the following two paragraphs in order that the motivation for the present invention, hereinafter summarized in the next section, may be better perceived.
U.S. patent application Ser. No. 096,960 teaches, in full sophistication, how transition-encoded information (once derived) may (then) be used to effect control of an image system marker, for example, a laser beam, which is generating an image. It is within this related application taught that transition-encoded information is preferably emplaced in two parallel random access memories (RAMs). For example, consider each RAM as 16K ×1. When there are less than 16K pixels in one scan line then there is one-to-one correspondence between pixels upon the scan line and addressable memory cells within each RAM. Envision each RAM as initially containing all 1's. Now in the first RAM, a flag, say a "0", is stored at the point of every transition upon the scan line from white to black. And, in the second RAM, a flag, say a "0" again, is stored at the point of every transition upon the scan line from black to white. These flags, and the addresses at which they are stored, constitute transition-encoded information. This transition-encoded information can be recorded in any order. The number of bits which are changed is equal to the number of transitions in the scan line (a number which is far less than the number of pixels). The process of making and recording this information is the process of the present invention (to which discussion will be returned to in the second following paragraph), and occurs independently of the image generation process.
During the generation (e.g., the printing) of a scan line both RAM's are simultaneously read. An address counter supplies the address for both RAMs, and this counter counts sequentially at the pixel clock rate. Every time the first RAM outputs a zero, a flip-flop is set to "black". Every time the second RAM outputs a zero, the flip flop is reset to "white". The state of the flip-flop is used to control the black, or the white, generation of successive pixels upon the scan line. For example, the flip-flop may control a laser beam to be "on" or "off", respectively generating white or black pixels in a positive image-generating system such as a video display unit, or respectively generating black or white pixels in a negative image-generating system such as electrostatic printer wherein the laser beam discharges selected areas of a photoconductive surface. Albeit oversimplified, as will be discerned from discussion of that refinement to transition-encoded data generation and use which is presented in copending U.S. patent application Ser. No. 096,959 this is the basic format of transition-encoded information and its basic use for generating pixels upon a scan line.
Summary of the Present Invention
The present invention concerns what transition-encoded information is (by definition), and how transition-encoded information is derived by transformation, or decompression, of run-length-encoded information. Run-length-encoded font image information does not use one piece of information for every pixel in the font image, but rather uses one piece of information for every transition. In this aspect it is quite different from bit-mapped information (into which it is often converted in the prior art) and is actually more similar to the transition-encoded information into which it is converted by the present invention taught within this disclosure.
Run-length-encoded font information contains the incremental distance between white/black transitions in the font image. For example, for a given character in a given font, the information might be interpreted as (1) there are 11 pixels from the left margin of the character box to the first transition, which is white to black; (2) then there are 22 additional pixels of black, (3) then 13 more pixels of white, (4) then 8 more pixels of black, and (5) that is the end of that character. It is common practice to store font information in PROM or on disk in such a run-length-encoded form. Usually the amount of information required is smaller than the required otherwise, especially when the resolution is very high. Run-length-encoded information may fairly be described as "compressed".
Image generation cannot transpire directly from this compressed run-length-encoded information. However, transition-encoded information may be quickly and efficiently produced from run-length-encoded information, and this transition-encoded information may be used for image generation as explained in the immediately previous Section 2. This production is called "decompression" because the transition-encoded information occupies more memory, albeit for but a short and temporary time during the generation of one scan line, than the run-length-encoded information from which it is derived.
The decompression of run-length-encoded information into transition-encoded information is done quickly and efficiently in a hardware system which runs "automatically" once a small amount of initial information has been supplied to it. Particularly, the hardware decompression system receives (i) the vertical position, (ii) the horizontal position, and (iii) a starting address in a font memory whereat a run-length-encoded description of a particular character font is stored (which image line is, in rudimentary form, a single line of print). The decompression system develops the transition-encoded information for a one scan line, of which scan lines an image line will normally contain many, at one time.
The transition-encoded information for each scan line is basically developed by adding, in an adder, the initial horizontal displacement address plus, in a cumulative fashion, the run-length-encoded font information for each character which appears, in a portion of such character, upon that scan line. The vertical position information is used to identify which characters within an image line may have portions within a particular one scan line of such image line. For example, the lower case character "a" may be generated using only roughly the lower half of these total scan lines which combinatorially generate a single image, or "print", line capable of showing both upper and lower case characters. Finally, certain counters, holding registers, and control codes make certain that the decompression of run-length-encoded data in order to generate successive scan lines of transition-encoded data is properly sequenced.
Collective Objects of the Related Inventions
It is one object of the collective inventions within the three related patent applications to achieve full bit-mapped performance, but at a cost and complexity far below that of a full bit mapped system. Still further, it is the objective of the three inventions to improve the processing speed over that speed otherwise available except at very high cost. This cost performance improvement is obtained because the image generator hardware system will perform "intelligent" operations which might usually be associated with the capabilities of, and operations performed by, a microprocessor.
Particular Objects of the Present Invention
It is one particular object of the individual present invention to efficiently and quickly transform, or decompress, run-length-encoded font information stored within a RAM into a new, non-bit-mapped, format of information called transition-encoded font information. This transition-encoded font information is usable to control the white or black generation of each pixel upon each scan line produced by an image generator. The transformation, or decompression, will be sufficiently efficient and quick when implemented with commonly available integrated circuit components so as to allow imaging (printing) on the order of 8 pages per minute (PPM) at 600 dots per inch (DPI) vertical resolution and 1200 DPI horizontal resolution, or 2 PPM at 2400 DPI vertical resolution and 1200 DPI horizontal resolution.
It is the further particular object of the individual present invention that the efficient and quick transformation, or decompression, of run-length-encoded font information into transition-encoded font information used for image generation is without any substantial limitations upon the numbers of fonts--ranging to over 1000--and the types of fonts--including logos, signatures, bar codes, pictographs and pictures as well as alphanumeric characters--which can be generated on demand at sizes from 4 to 255 points. In other words, speed of imaging within the present invention is not purchased at the cost of either the complexity nor of any functional limitations regarding the diverse image generated.
It is a further particular object of the individual present invention that transition-encoded font information should be used to control the generation of successive black or white pixels within a raster scan line at high speed. Particularly, 1200 pixel dots per inch (DPI) will be placed across a horizontal scan line of greater than 8.5 inches in length within a time period of less than 1100 microseconds (1/900 second) by the use of only common, readily available, integrated circuit components. All control of the marking is from the transition-encoded font information which is decompressed, in real time, from run-length-encoded information.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a representation of the control of an image system marker by transition-encoded information in accordance with the present invention.
FIG. 2 shows a block diagram of an image processing system including an image generator hardware processor wherein the present invention resides.
FIG. 3 shows a functional block diagram of the present invention for decompressing run-length-encoded font information to transition-encoded font information.
FIGS. 4a and 4b (hereafter referred to as "FIG. 4") show a hardware block diagram of the present invention for decompressing run-length-encoded font information to transition-encoded font information.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention resides within an image generator, or processor, which is nominally used as an intelligent controller for a non-impact, laser, printer. The image generator, and present invention, can be used for generating images which are not printed, such as those appearing on a video display unit. The image generator uses real-time raster scan techniques in accordance with the present invention and related inventions to create typeset quality images of 1200 horizontal×1200 vertical dots per inch (DPI) at the rate of four 8-1/2"×11" pages per minute (PPM). At such resolution and speeds the image generator must supply pixel by pixel information to turn the image marker--a laser beam--"on" and "off" at speeds up to 35 MHz. The present invention and related inventions allow accomplishment of this high speed control without requiring those very large amounts of high speed, and expensive, memory which would be required by prior art full bit mapped raster scan techniques.
Some rationale for the approach by the present invention and related inventions is as follows. As discussed in the Background of the Invention section, a bit-mapped representation of an entire image line uses considerable amounts of high speed and expensive random access memory (RAM). An image line is of variable height dependent upon the type of font and the font height (from 4 to 255 points) being represented, and is nominally 8.6 inches in width. An image line is normally comprised of a large number of horizontal scan lines. Thus it might be investigated if RAM requirements could be reduced by bit-mapping at the scan line, as opposed to the image line, level. For the 8.6" wide image area, and at 1200 dpi, there are 10,320 pixels in each scan line. A straightforward approach would be to try to prepare a bit-mapped RAM storage wherein each address is one pixel and wherein a stored "1" represents black while a stored "0" represents white. This turns out to be a brute force approach to producing the information needed to control the pixel by pixel, black and white, generation upon a scan line. Moreover, at high pixel rates of scan line generation there is insufficient time, at least when using common integrated circuit semiconductor components, to prepare an approximate 10,320 addresses of bit-mapped RAM storage during an approximate 1100 microsecond generation of each scan line. The present invention and related inventions use an alternative approach to the prior art bit-mapped control of pixel generation.
In this alternative approach a memory space of 16,384 pixels (10,320, plus unused extras) is mapped out twice; once for white-to-black transition points, and a second time for black-to-white transition points. The representation of this mapping is shown in FIG. 1. Although one physical RAM could be mapped two time--once with a first-type flag at white-to-black transition points and again with a second-type flag at black-to-white transition points--it has been found that the use of two parallel RAM's is advantageous. The black-to-white transitions are recorded in a nominal first random access memory RAM1, and the white-to-black transitions are recorded in random access memory RAM2. Within FIG. 1 the left-to-right extension of the lines at RAM1 and RAM2 represent the memory addresses (10,320+) of each random access memory while the vertical "tick marks" represent the relative locations within each random access memory whereat the flags are stored.
Observing FIG. 1, the convention is employed that each RAM is initially written to all 1's, (shown as a high level) and each transition indicated by a "0" (shown as a low-going spike). It may immediately be recognized that information is not required to be written into the RAMs for every pixel. All that is necessary is to determine whether each transition within run-length-encoded font information represents black-to-white or white-to-black, and to insert that information into the proper address of the proper one of each of two initialized RAM's. The information about transitions which is inserted into random access memory at certain addresses, corresponding to pixels, at which such transitions occur is called transition-encoded information.
In the approach to image generation of the present and related inventions, the transition-encoded information within the two RAMs--RAM1 and RAM2--will be dumped simultaneously sequentially during the printing of each scan line. The dumping will start when the start of scan (SOS) signal from the marker system, e.g. from a laser scanner, indicates the beginning of a scan line.
An address counter supplies the address for both RAMs, and this counter counts sequentially at the pixel clock rate. As a somewhat simplified explanation of the process of generating an image scan line, every time the RAM1 outputs a zero, a flip-flop is toggled to "black". Every time the RAM2 outputs a zero, the same flip-flop is toggled to "white". This simplified explanation is sufficient for understanding the basic process of converting from transition-encoded information to control of the white and black generation of pixels upon a scan line. The control of the marker responsive to the example flags stored in RAM1 and RAM2 is illustrated as line BLACK/WHITE shown in FIG. 1.
The image generation approach of the present and related inventions, which approach is based on transition-encoded information, has been outlined above. However, further sophistication appears in the actual best mode implementation of the approach in a high performance image generator. For example, consider in light of the above simplified discussion of the approach that if it is attempted to twice identify a single given pixel as representing an "on" transition--such as might reasonably occur for two overlapping character fonts--and then identify each of two separate other pixels as representing "off" transitions, then an error will occur. Mainly, the marker has been turned "on" but once while being turned "off" twice. Thus, in the simplification, it is possible to have overlapping characters; but only to an extent. "On" transitions must not coincide, and "off" transitions must not coincide. This restriction is a limit which makes the simplified scheme different than a full bit-mapped scheme.
A block diagram generally showing the hardware environment--a complete image generator--of a preferred embodiment of the present invention for particular use in a laser printer, and particularly showing this preferred embodiment of the present invention as a HARDWARE PROCESSOR, is shown in FIG. 2. The entire image generator block diagrammed in FIG. 2 converts ASCII character information into pixel by pixel control of a raster scanning laser printer. The image generator is managed by two microprocessors, nominally including a first microprocessor uP1 210 type 68000 controlling external communications to and from a computer or the like, handshakes with the printer engine, and the placing of data within the font memory RAM/FONT BOARD 300. A second microprocessor uP2 220 type 68000 interacts with the same font memory RAM/FONT BOARD 300 to move certain initial data to the HARDWARE PROCESSOR 100 in response to a print command. This certain data, which is in the nature of the vertical and horizontal position at which printing is to transpire and the first address of a font which is to be printed from the location of this upper left-hand corner pixel, will be more completely discussed in conjunction with upcoming FIGS. 3 and 4. The second microprocessor uP2 does not do the decompression of run-length-encoded data into the transition-encoded data which is used to control the black/white transitions of the print engine. Rather, it just "kicks off" each font which is to be printed, and where (including in overlapping position) the font is to be so printed, and then the HARDWARE PROCESSOR in accordance with the present invention will attend to all necessary control of the laser marker of the printer.
The exact sequence of "feeding" run-length-encoded font information, and positional information, to the HARDWARE PROCESSOR 100 could be accomplished in diverse ways. One way is to store a most condensed run-length-encoded form of font information in the FONT PROMS 310 part of the RAM/FONT BOARD 300, or, alternatively and additionally, upon a hard disk which is accessed through HARD DISK CONTROLLER BOARD 400. In accordance with the font size, or scaling, received from the computer HOST via the 2 UARTS, 1 PARALLEL PORT 500 the first microprocessor uP1 210 expands the run-length-encoded information (still as run-length-encoded information, now scaled) and emplaces it in the dynamic RAM of the SOURCE FILE, part of the RAM within the RAM/FONT BOARD 300. The first microprocessor uP1 in response to input commands also assembles a complete PAGE TO BE PRINTED FILES 320, part of the RAM/FONT BOARD 300 which contains a page image entirely in (appropriately scaled) run-length-encoded information. This is a modest amount of work, but a large and highly time contrained task remains in controlling the black/white state of the print engine marker to image this information during high speed scan lines of approximately 10,320 pixels each during a scan time period of approximately 1100 microseconds. This task is initiated by the second microprocessor uP2 220 which reads the PAGE TO BE PRINTED FILES 320 and, responsively thereto, places information regarding which character and which font (i.e., what starting address within the FONT PROMS 310), horizontal position, and vertical position within the HARDWARE PROCESSOR 100. The HARDWARE PROCESSOR 100 takes this initial information, basically in the nature of commands or directives, and uses it to extract appropriate compressed font run-length-encoded information from the dynamic RAM of the RUN LENGTH FILES 321, and to assemble the "on" and "off" transition addresses of the transition-encoded information. From this transition-encoded information the RUN LENGTH TO PIXEL GENERATOR 110, which is more completely explained in companion U.S. paten application Ser. No. 096,960, will control the LASER of the print ENGINE to turn it "on" and "off", producing respective white and black imagery "on the fly".
Before discussing (in conjunction with FIG. 4) the actual hardware of the HARDWARE PROCESSOR 100 (previously shown in FIG. 2) which performs the decompression of run-length-encoded information to transition-encoded information, it is useful to better understand the theory of this transformation. Accordingly, a functional block diagram of the decompression in accordance with the present invention is shown in FIG. 3.
Within the block diagram of FIG. 3 which is functional, and not of hardware (although correspondence to certain hardware elements previously seen in FIG. 2 and upcoming in FIG. 4 may be generally noted), a CONTROL SYSTEM places the horizontal position of the start of a character in the FIRST HORIZONTAL POSITION REGISTER, and it places the first RAM location where appropriate compressed run length information regarding that character will be in an ADDRESS COUNTER. (Because the CONTROL SYSTEM can astutely be identified to have correspondence to the second microprocessor uP2 220, and since the RAM location is within the PAGE TO BE PRINTED FILES 320 which are both shown in FIG. 2, there is a natural tendency to try to commence looking at FIG. 3 as a hardware block diagram. This tendency is regrettably reinforced because words like "COUNTER", "MEMORY", REGISTER", and "ADDER" appearing in FIG. 3 have meanings associated with hardware elements as well as with function. However, it is better that the hardware, which exhibits the complex paths to be further shown in FIG. 4, should be placed in the background for the moment and that the transformation function which is diagrammed in FIG. 3 should first be understood. Forbearing this functional understanding, the actual hardware elements and their interconnections are likely to prove confusing.)
Using that address information, the RANDOM ACCESS MEMORY produces data indicating the number of pixels interval between the left edge of the character box and the first transition (e.g. white to black). That information is combined with the initial position information in an ADDER in order to obtain a TRANSITION ADDRESS. This transition ADDRESS is fed back into the FIRST HORIZONTAL POSITION REGISTER and latched. Meanwhile, the CONTROL SYSTEM produces a pulse which is counted by the ADDRESS COUNTER, causing that the next location in RAM is accessed. This results in a second TRANSITION ADDRESS wherein another transition is located, e.g. black to white. With each count by the address counter, a one-bit counter or FLIP-FLOP toggles to indicate a reversed polarity of transition occurring on alternate transition addresses. This continues until the last transition for that character has been produced. The control system senses a stop bit being produced by the RAM at the last transition in each line. Moreover, the control system senses a stop code at the end of the character. The transition addresses are also supplied as addresses to each of two 16K×1 RAMs, and the output of the previously mentioned FLIP-FLOP causes O's to be stored alternately in the first, and in the second, 16K×1 RAM. The end result is that the each 16K×1 RAM contains transition information.
When the information is completed for a first character, the process is then repeated for each character on each line. When each character is completed, the contents of the ADDRESS COUNTER are saved, so that at a corresponding point on the next scan line the address counter, and resultant RAM addressing, will start where it had previously left off.
A hardware block diagram of preferred embodiment of a HARDWARE PROCESSOR 100 (previously seen in FIG. 2) in accordance with the present invention, and for decompressing, or transforming, run-length-encoded information into transition-encoded information, is shown in FIG. 4. The MICROPROCESSOR CONTROL SYSTEM uP2 220 loads information for vertical position (16 bits), horizontal position (16 bits) and font start address (24 bits), respectively into the VERTICAL POSITION LATCH 101, the HORIZONTAL POSITION LATCH 102, and the FONT START ADDRESS LATCH 103. It then picks an address location which is known to be available, and loads that information in the WRITE ADDRESS LATCH 104. A automatic sequence causes the aforementioned 56 bits of information to be loaded into one address of the 2K×56 BIT RAM 108. During this process, selector S2 106 is set to convey information from the WRITE ADDRESS LATCH 104 to the address input of the 2K×56 BIT RAM 108. At all other times selector S2 106 is set to convey the RAM ADDRESS COUNTER 105 information to the 2K×56 BIT RAM 108 address input. Moreover, during this time selector S1 107 is set to convey information from the FONT START ADDRESS LATCH 103 to the 2K×56 BIT RAM 108. Writing to this RAM 108 occurs by cycle stealing, i.e. all other processes which might be operating are interrupted for one clock cycle in order to permit writing information into this RAM 108.
The information that has been loaded into the RAM 108 is the (x,y) position on the page whereat an upper left corner of a font is to be generated, together with the address, in the DYNAMIC MEMORY 320/FONT RUN LENGTH INFORMATION 321, of where that particular font begins to be described in (previously appropriately scaled) run-length-encoded information. The DYNAMIC MEMORY 320/FONT RUN LENGTH INFORMATION 321 was previously called the PAGE TO BE PRINTED FILES 320 and the RUN LENGTH FILES 321, in FIG. 2.
Once for every scan line in a raster scanned image generating system, the RAM ADDRESS COUNTER 105 is caused to sequence through all addresses of the 2K×56 BIT RAM 108, which will permit the processing of every character's information which is resident there. Up to 2K characters which have some part of such character falling anywhere upon a given scan line may thus be represented. Normally the number of characters which might fall on a given scan line is less than 1/10 of 2K, and may typically be as few as the number of alphanumeric characters which are typically within a single print line. Immediately, however, it is obvious that the decompression and the resultant image generation in accordance with the present invention is well able to take in stride very numerous and correspondingly narrow (less than an average of 6 dots wide at 1200 dpi) characters or, as is more commonly the case, overlapped and multiply overlapped and densely multiply overlapped characters.
Once for every sweep of a scan line, a SOS (start of scan) signal is generated. In a laser print engine scanning a laser beam by an oscillating or by a rotating mirror, this SOS signal might typically be generated responsively to the mirror position. This SOS signal causes the VERTICAL POSITION COUNTER 111 to increment. This COUNTER 111 refers to the current vertical position on a page of the scanning beam. The vertical position of a given character to be potentially printed (for which certain information is contained within the RAM 108) is, during each scan cycle when all information is checked, compared with the VERTICAL POSITION COUNTER 111 in comparator 112. If the vertical position on the page whereat a character is to be printed is advanced further down the page than that position where the scanning beam currently is, then the VPOK (for Vertical Position OK) signal is taken by the control system to inhibit any action for that character or RAM position.
Once the VPOK signal indicates, for a given character, that that character's vertical position is at or in arrears of the current vertical position of the scanning beam, then the control system causes information for that character to be processed. The information is processed in the following three steps, or cycles, plus a fourth step if an end code is seen.
In a first step, the 2K×56 BIT RAM 108 is read, causing the FONT ADDRESS COUNTER 109 to be loaded with a font address. Moreover, selector S4 113 conveys the horizontal position information from RAM 108 to the HP ADDER 114. The DRAM GATE signal is low, so that this gated horizontal position information is added to zero, and is then stored unchanged in the HORIZONTAL SUM LATCH 115.
In a second step the FONT ADDRESS COUNTER 109 provides address information to the DYNAMIC MEMORY 320, which contains run-length-encoded font information. The resulting Dout (data out) read from the DYNAMIC MEMORY 320 is gated to the HP ADDER 114, with the DRAM GATE signal being now high. At this time selector S4 113 acts to convey information from the output of the HORIZONTAL SUM LATCH 115 to the upper input of this HP ADDER 114. This makes that at the conclusion of the step, or cycle, when the output of the HP ADDER 114 is latched, then the HORIZONTAL SUM LATCH 115 will contain the sum of the original horizontal position (obtained from the 2K×56 BIT RAM 108) and the offset to the first transition (obtained from the DYNAMIC MEMORY 320). When the information is valid, then selector S5 116 will act to gate this information as signal ADDR to select an address in each of the two transition memories, namely the WHITE TO BLACK TRANSITION RAM 16K×1 117, and the BLACK TO WHITE TRANSITION RAM 16K×1 118. The BLACK/WHITE FLIP-FLOP 119 is initialized to a state which permits this address information to be relevant to and used by the WHITE TO BLACK TRANSITION RAM 16×1 117, but not to or by the BLACK TO WHITE TRANSITION RAM 16K×1 118. A single-bit "transition occurs here" record is then stored in the former of the two RAMs 117,118. This record, or flag, is the beginning assembly of transition-encoded information. At the conclusion of this second cycle, the FONT ADDRESS COUNTER 109 is incremented.
The next, third, step or cycle is quite similar to the second step above, except for the following two occurrences. First, the BLACK/WHITE FLIP-FLOP 119 is now toggled so as to make the BLACK TO WHITE TRANSITION RAM 16K×1 118 record the information which is generated, instead of the WHITE TO BLACK TRANSITION RAM 16K×1 117. Second, the HORIZONTAL SUM LATCH 115 records the sum of the previous information, plus whatever offset is presented from the DYNAMIC MEMORY 320.
At the conclusion of this third step, the COMPARATOR 120 checks the most significant bit (which is not used by the HP ADDER 114 when the BLACK/WHITE FLIP-FLOP 119 is set for black/white transitions), and if that bit is high, this transition is considered to be the end of the character. If this is not the case, additional steps, or cycles, equivalent to steps two and three are repeated until such an end code is seen.
If such an end code is seen, then the following fourth step, or cycle, is then executed. The font contents of the FONT ADDRESS COUNTER 109 are written back into the 2K×56 BIT RAM 108 (with the selector S1 107 controlled to convey such information). Thus for the next scan line, the new font address information will start where the old font address information left off.
After steps one through four have been completed for a given character, then the RAM ADDR COUNTER 105 is incremented, and these four steps are repeated for each successive character until all of the potentially up to 2K characters which are potentially upon a single scan line have been processed. This processing has completely converted run-length-encoded information into transition-encoded information for a single scan line of the image generator.
The foregoing decompression, or conversion, or processing has served to record in the WHITE TO BLACK TRANSITION RAM 16K×1 117, and in the BLACK TO WHITE TRANSITION RAM 16K×1 118, the locations of the respective white-to-black and black-to-white transitions along a given scan line. Once this information has been recorded, then selector S5 116 is set to select the PIXEL POSITION COUNTER 121 to sequence through the memory locations of RAMs 117,118 in parallel, and to read the transition-encoded information stored therein. This information is read in parallel to the BLACK/WHITE COUNTER 122, and used to count down and/or count up this COUNTER 122. In the count so obtained, the most significant bit, or sign bit, is used to modulate the marker of the scanning system, or the LASER ON/OFF CONTROL AT THE PRINT ENGINE. The signal PIXEL CLOCK which feeds the PIXEL POSITION COUNTER 121 is a clock which completes one cycle for each and every advancement of the scanning beam by one horizontal pixel in distance. This counter 121 is reset at the beginning of each scan line.
The COMPARATOR 120, when sensing information from the DYNAMIC MEMORY 320, also checks for a unique code (nominally "FF") which, when seen, indicates the end of the run-length-encoded information for the entire character font. When this code is seen, then the contents of the FONT ADDRESS COUNTER 109 are changed to represent an address out of range, which address is then recorded by the 2K×56 BIT RAM 108. When this same location in RAM 108 is next interrogated, then the control system interfacing with the HARDWARE PROCESSOR will check not only for VPOK (mentioned above), but also for a font address (as supplied to DYNAMIC MEMORY 320) which is within a permissible range. If this permissible font address is not seen, then (further) image generation in response to that character is skipped. Thus characters may be skipped, or suspended from being actively used to control image generation, either because (1) their vertical position places them in a "waiting" status, or (2) their font address indicates that that character has been completely processed.
It should be noted that there are two types of stop codes for each font character. The first code suspends the reading of information for a given scan line, to be resumed on the next scan line. This code is a high, most significant, bit on the black duration information bytes (not being continuation bytes). The second code, as mentioned above, suspends information about the entire character.
Because of this detection of font addresses out of range, the second microprocessor uP2 220 (shown in FIG. 2) knows which locations in the 2K×56 BIT RAM 108 will have information which is no longer required, and thus information for new characters to be subsequently printed may be loaded in those locations.
Not shown in the block diagram of FIG. 4, to avoid complexity, is a further check of the run-length-encoded information received from DYNAMIC MEMORY 320 to look for another unique code (nominally "FE" or "7E"), which indicates that the spacing between successive transitions is too large to be represented in just a single byte. If that is the case, then the HORIZONTAL SUM LATCH 115 sums its old information plus the unique code, but no writing of that information occurs into the white/black or black/white transition RAMs 117,118, nor does the BLACK/WHITE FLIP-FLOP alter its state. The contents of the next location read from the DYNAMIC MEMORY 320 are added in as well, and if this unique code is not again repeated in that location, a transition is recorded. | Transition-encoded information for a single scan line of a font image consists of flags at the addresses of all points of transition upon the scan line from black to white, and from white to black, in order to generate one scan line of the font image. This information is produced, scan line by scan line, in a system receiving the vertical position, the horizontal position, and a starting address within a font memory whereat a run-length-encoded description of a particular character font is stored. This information is developed by adding, in an adder, the initial horizontal displacement plus, in a cumulative fashion, the run-length-encoded font information for each character which appears, in some portion, upon an individual scan line. The transition-encoded information is used to control pixel by pixel image generation in an image generator equivalently to full bit-mapped control but with lower cost, higher speed of conversion, and greater flexibility in the images generated. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to stepladders. More particularly it concerns stepladders made of extruded aluminum metal parts structured so the ladders will be extremely light and of low cost, but still strong and substantially free of torsional twisting, pantographing or relative rotation of parts.
2. Description of the Prior Art
Ladder manufacturers strive to create ladders from a minimum of parts and material to make them as light weight and as low in cost as possible. Stepladders designed with such considerations in mind are disclosed in many prior patents, e.g., U.S. Pat. Nos. 2,899,008 and 3,009,535.
There tends to be a trade-off in ladder construction between strength and stability versus light weight and minimum material of construction. Thus, as the number of parts and weight of material used in fabrication of ladders is decreased, there is an increased tendency for the strength and proper functioning of the ladders to decrease. By way of example, light weight stepladders frequently exhibit unsatisfactory torsional twisting of the rear section relative to the front section during use. Also, pantographing or rotation often occurs in the rear sections of light weight ladders. Moreover, proper bracing of the front section and bucket rack support are problems in such ladders.
Not withstanding the large number of new designs of ladders that have been developed over the years, there continues to be a need for the creation of stepladders that possess high strength and stability combined with light weight, low material requirement and low cost of fabrication.
OBJECTS
A principal object of the present invention is the provision of new improvements in stepladders. Further objects include the provision of stepladders that:
(1) Are of light weight, but have good strength and stability,
(2) Are formed of extruded aluminum parts structured to require a minumum of rivets for assembly.
(3) Mitigate torsional twist, pantographing or rotation in the rear prop section.
(4) Incorporate unique front section braces.
(5) Include novel bucket rack brackets.
Other objects and further scope of applicability of the present invention will become apparent from the detailed description given hereinafter; it should be understood, however, that the detailed description, while indicating preferred embodiments of the invention, is given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
SUMMARY OF THE INVENTION
The foregoing objects are accomplished in accordance with the present invention by a stepladder construction that is characterized by the following features:
A. a top plate of reduced width relative to the width of the ladder steps,
B. a front section comprising metal channel side rails and steps,
C. a rear section comprising metal channel side rails and horizontal brace members that have notched out ends fitted to the side rails providing purchase or leverage to prevent pantographing or rotation without need for diagonal bracing.
D. a bucket rack pivoted on special contoured bracket members fixed by a single rivet to the rear section side rails.
E. lower front section bracings that are attached to rubber feet rivets and grasp the rubber feet in their mounting to their respective siderails.
F. upper front section bracing structured so a single rivet may be used for its attachment in the center of a step of the ladder.
BRIEF DESCRIPTION OF THE DRAWING
A more complete understanding of the new stepladders of the invention may be had by reference to the accompanying drawings in which:
FIG. 1 is a perspective view of a stepladder constructed in accordance with the invention
FIG. 2 is a fragmentary side view of the top portion of the ladder
FIG. 3 is a fragmentary rear view of the top portion of the ladder
FIG. 4 is an exploded view of the rear section pivot bracket portion of the ladder
FIG. 5 is a fragmentary sectional view taken on the line 5--5 of FIG. 3
FIG. 6 is a fragmentary sectional view taken on the line 6--6 of FIG. 3
FIG. 7 is an exploded view of the bucket rack bracket shown in FIG. 6
FIG. 8 is a sectional view taken on the line 8--8 of FIG. 1
FIG. 9 is a sectional view of the bottom portion of the ladder front section taken of the line 9--9 of FIG. 1
FIG. 10 is a sectional view taken on the line 10--10 of FIG. 9
FIG. 11 is a sectional view of the rear section brace member taken on the line 11--11 of FIG. 1
FIG. 12 is a sectional view taken on the line 12--12 of FIG. 11
FIG. 13 is an exploded view of one end of the rear section brace member shown in FIGS. 11 and 12
FIG. 14 is a sectional view of the step of a modified form of the ladders of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring in detail to the drawings, the new stepladder 2 comprises a front section 4, a rear section 6, a bucket rack 8 and means 10 for pivotally connecting the rear section 6 to the front section 4.
The front section 4 comprises left side rail 12 and right side rail 14, a plurality of equally spaced apart steps 16 fixed between the side rails and a top plate 18 fixed between the side rails at the top thereof. The distance between the uppermost step 16a and the top plate 18 is greater than the distance between the steps 16.
The side rails are formed of channels having a face 20 and two normal legs 22 and 24. Similarly, the steps 16 are formed of channels each having a face or tread 26 and two normal legs 28 and 30. Also, top plate 18 is formed of a channel having a face 32 and two normal legs 34 and 36.
The rear section 6 comprises left side rail 38, right side rail 40 and a plurality of spaced apart, horizontal brace members 42. The side rails 38 and 40 are channels having a face portion 44 and normal leg portions 46 and 48 that extend forward of the face portion 44 in the ladder.
The brace members (see FIGS. 11-13) are I-shaped metal strips defined by the central web 50 and cross portions 52 and 54, the latter being cut on one side at the ends 56 forming a ledge 58 at each end. The face portion 44 of side rail 38 is fixed by rivet 60 to the ledge 58 with the inside leg 46 abutting the side edges 62 of the cross portions 52 and 54. The right rear side rail 40 is similarly fixed to the other end 64 of the brace member 42 by the rivet 66.
The rear section pivot means 10 comprises first and section L-shaped brackets 68 and 70. Each bracket has a base portion 72 of each of the brackets 60 and 70 is fixed by a rivet 76 between the rear legs 24 of the front side rails 12 and 14 and the rear leg 36 of the top plate 18 with the leg portion 74 of each bracket 68 and 70 extending beyond the face portion 20 of the respective front section side rails 12 and 14. The rear section side rails 38 and 40 are each pivoted at the top end 78 thereof upon the leg portion 74 by a rivet 80. Advantageously, the brackets 68 and 70 have an lug 82 that overlaps the face 20 of the side rail 12 or 14 respectively to further strengthen the bracket structure. Also, the leg portion 74 of each bracket 68 and 70 has a notch 84 that receives the bead 86 on the end of the leg 24 of the side rails 12 and 14 respectively.
The top of each rear side rail 38 and 40 is fitted with a cap 88 having lugs 90 at the sides 92 and 94 that can be locked into the holes 96 and 98 respectively in the top ends 78 of the side rails 38 and 40.
The caps 88 are strengthen by depending webs 97 and 99.
The steps 16 and top plate 18 are fixed at each side to the side rails 12 and 14 by front rivets 100 and rear rivets 101.
The bucket rack 8 comprises cross slats 102 and 104 and left and right L-shaped support members 106 and 108 respectively fixed together by the rivets 110.
The bucket rack 8 is pivoted on rivets 112 that extend through the inner legs 46 of the rear side rails 38 and 40. A Contoured bracket member 114 is held by the rivets 112 between the respective side rail 38 and 40 and the support members 106 and 108 respectively.
Each of the two bracket members 114 consists of a central web 116, two dependent webs 118 and 120, an L-shaped end portion 122, a stop element 124 and lugs 126 and 128. In the assembled ladder, a washer 130 is positioned between the vertical leg 132 of support member 106 or 108 and the exposed edges 134 and 136 of webs 118 and 120 respectively.
The lug 126 of bracket member 114 engages the face 44 of the rear side rail and the lug 128 embraces the rear edge 138 of leg 46 thereby firmly locking the bracket member 114 to its respective rear side rail 38 and 40.
As seen in FIG. 6, upon lowering the bracket rack 8 by the movement in the direction of the arrow, the rear ends 140 of the support members 106 and 108 will be stopped in a horizontal position by the stop elements 124. This bucket rack bracket arrangement, therefor, enables the rack and brackets all to be fixed upon the ladder in a fully operative manner by only two rivets. Furthermore, it allows the use of a squarely constructed bucket rack instead of a tapered one as is normal for accomodation to the flair of the front section side rails. Independent attachment of the bucket rack brackets is eliminated along with attachment rivets so that by the use of the specially contoured brackets that lock to the siderails and torsional movement thereof is prevented. The entire assembly is uniquely held, supported and hinged by a single rivet on each side.
The front section 4 is braced by upper brace means 142 and lower brace means 144. The former comprises a pair of straps 146 riveted at their outboard ends by rivets 148 to the legs 22 of the respective siderails 12 and 14. The inboard ends of straps 146 are fixed by a single rivet 150 to the leg 30 of a step e.g., the top step 16a.
The lower brace means 144 comprises a pair of U-shaped channel strips 152 fixed at the top end 154 to the under surface of face 26 of the bottom step 16 by rivets 156. The bottom ends 158 of the strips 152 are fixed by rivets 160 to the faces 20 of the side rails 12 and 14 with the vertical portion 162 of the T-shaped molded foot pads 164 locked in between. Hence, by the use of only four rivets the molded rubber foot pads 164 and the lower brace means 142 are fastened to the ladder providing added strength and stability to the new stepladders.
The embodiments of the new ladders as illustrated in FIGS. 1-10 have front section side rails nearly as wide as the tread 26 of the steps 16. In the modification shown in FIG. 14, the side rails 166 are narrower in width than the side rails 12 and 14. To accomodate this, the steps 168 have a tread 170 that extends both fore and aft beyond the side rail 166 and the legs 172 and 174 are set further in on the step as compared to the legs 28 and 30 of the steps 16.
CONCLUSION
New stepladder constructions have been described that prevent torsional twisting or pantographing in the rear section even though the ladder sections are made of a very limited number of parts and fasteners. These results are due, in part, to the creation of unique bracket members for the bucket rack and rear prop section. Additionally, the front section of the ladders have cross bracings that require a minimum of fasteners while providing full purchase and leverage against pantographing or rotation in the front section. Consequently, the ladders are of extremely light weight and may be produced at low cost. | Stepladders are made of extruded aluminum metal parts including special bracket members for the rear prop section and the bucket rack that mitigate torsional twist. Cross bracings for the rear prop section and bracings of the front section are structured to prevent pantographing or rotation and reduce to a minimum the number of rivets required for ladder assembly thereby providing strong, safe ladders of light weight and low cost. | 4 |
BACKGROUND OF THE INVENTION
This invention was made with Government support under Contract No. AFOSR-88-0334 awarded by the Air Force. The Government has certain rights in this invention.
This invention relates to the growing of superlattice structure and, more particularly, to a method for growing a superlattice structure on a substrate comprising the steps of, creating a periodic array of monoatomic surface steps on the substrate comprised of a plurality of equal and adjacent monoatomically thick steps on the surface of the substrate at an area to have the superlattice structure grown thereon; providing means for creating a beam of a material being input thereto and control means operably connected for selectively including or not including respective ones of a plurality of materials within the beam; directing the beam at the steps of the substrate; and, causing the control means to include and not include respective ones of the materials within the beam in a pre-established pattern of time periods which will cause the materials to be deposited on the steps in a series of stacked monolayers.
This invention is an improvement to the basic technology of U.S. Pat. No. 4,591,889 issued May 27, 1986, of which co-inventor Pierre M. Petroff, hereof was a co-inventor. That patent entitled SUPERLATTICE GEOMETRY AND DEVICES, as the title suggests, was to the basic geometry of a superlattice structure and possible devices of a general nature that could be constructed with such a geometry. The patent suggests that the geometry of the structure could be grown employing molecular beam epitaxy equipment and techniques as known in the art. In particular, the teaching of that patent is shown in simplified form in FIGS. 1-4 hereof. As depicted in FIG. 1, a substrate 10 having equal and periodic steps 12 on the upper surface thereof is first formed. It is suggested that a buffer layer of a substrate-like material may be grown on the steps 12 to improve the texture of the steps. The materials comprising the layers are then deposited on the steps 12 in the manner of FIGS. 2 and 3. As depicted in FIG. 2, the first material 14 (indicated by the X's) is grown through a molecular beam epitaxial process. The amount of the first material 14 grown in each step 12 is suggested as being controlled by use of a shutter system t block the source of the molecular beam of the first material. As taught in that patent, the deposited atoms of the first material 14 tend to migrate to the edges 16 of the steps 12 and, therefore, form a first region on each step 12 adjacent the edge 16. The depth of the region of the first material 14 is controlled by the amount of the first material 14 which is grown on each step 12. This, of course, is a function of the amount of time the "shutter" controlling material 14 is open.
As depicted in FIG. 3, the second material 18 (indicated by the O's) is also grown through a molecular beam epitaxial process. The amount of the second material 18 grown on each step 12 is also controlled by use of a shutter system to block the source of the molecular beam of the second material. Again as taught in that patent, the deposited atoms of the second material 18 tend to migrate to edges--in this case, the edges 20 of the first material 14--and, therefore, form a second region on each step 12 adjacent the first material 14. The depth of the region of the second material 18 is also controlled by the amount of the second material 18 which is grown on each step 12 which, again, is a function of the amount of time the "shutter" controlling material 18 is open.
Each layer or region of the first and second material 14, 18 as depicted in FIGS. 2 and 3 is actually only a few angstroms (Ås) thick. The process of growing layers comprised of the first and second regions of the materials 14, 18 is repeated until vertical layers 22 and 24 of the materials 14, 18, respectively, are created. As also taught in that patent, by varying the widths of the regions with respect to the width of the steps, the layers 22, 24 can be made to tilt. Thus, if the widths or thicknesses of the layers are designated as m and n and the width of the steps is considered as 1, the layer, 22, 24 will be vertical if m+n is close to 1. As can be appreciated from FIGS. 3 and 4, if m+n>1, the material 18 layer of each step 12 will overlap the material 14 layer of the next adjacent lower step 12 slightly as the figures are viewed. As repeated layers of the same dimensions are grown, it an be seen that the layers 22, 24 will tilt to the right as the figures are viewed. In addition to the formation of vertical and tilted superlattice structures, the patent also suggests the formation of quantum well wires, for example, by combining solid layers with vertical or tilted layers so that a transverse conductive layer (i.e. a quantum well wire) is formed being contained on all sides by materials into which no electrical flow can occur. The patent also suggests a possible structure according to the invention disclosed therein which, when pumped, yields as solid state laser lasing at more than one frequency.
The teachings of the above-referenced prior art patent suffer from only one shortcoming--they reflect theoretical structures and methods of forming them; in other words, while the superlattice structures disclosed therein are useful and the inventors herein have found that they can, in fact, be produced using molecular beam epitaxy equipment, the techniques known in the art at the time of the invention for the use of such equipment when applied to producing superlattice structures in the manner suggested by the invention proved to be less than ideal. Since those structures were never produced by the inventors of the above-referenced patent, the best mode for carrying out the invention was merely a best guess based on technology known to the inventors at the time and previously employed by them for other purposes. The structures produced experimentally by the inventors herein starting with the teachings of that patent, while suitable for laboratory testing and proving the viability of the concept, were less than suitable for commercial production of devices employing such superlattice structures and geometry therein.
Wherefore, it is an object of the present invention to provide methods for the growing of superlattice structures which can be used for producing solid state devices incorporating superlattice geometries therein which are practical for commercial production purposes.
It is another object of the present invention to provide methods for the growing of superlattice structures which can be used for producing solid state devices incorporating superlattice geometries therein in which the parameters of the grown layers can be accurately controlled.
It is still another object of the present invention to provide methods for the growing of superlattice structures which can be used for producing solid state devices incorporating superlattice geometries therein in which the quality and separation of materials comprising the grown layers can be closely controlled.
Other objects and benefits of the present invention will become apparent from the detailed description which follows hereinafter when taken in conjunction with the drawing figures which accompany it.
SUMMARY
The foregoing objects have been achieved in the method of the present invention for growing a superlattice structure on a substrate by depositing elements thereon in a stacked series of monolayers comprising the steps of, creating a periodic array of monoatomic surface steps on the substrate comprised of a plurality of equal and adjacent monoatomically thick steps on the surface of the substrate at an area to have the superlattice structure grown thereon; providing means for creating a beam containing the elements to be deposited and control means operably connected for selectively including or not including respective ones of the elements within the beam; directing the beam at the steps of the substrate; and, causing the control means to include and not include respective ones of the elements within the beam in a pre-established pattern of time periods which will cause the elements to be deposited on the steps in a series of stacked monolayers.
In one embodiment wherein Al, Ga, and As are to be deposited on a substrate to form stacked monolayers of AlAs and GaAs, the step of causing the control means to include and not include respective ones of the elements within the beam in a pre-established pattern of time periods includes the steps of:
(a) first depositing sufficient atoms of Al to form an Al monolayer;
(b) next depositing sufficient atoms of As to combine with the Al monolayer to form an AlAs monolayer;
(c) then depositing sufficient atoms of Ga to form a Ga monolayer adjacent the Al monolayer;
(d) next depositing sufficient atoms of As to combine with the Ga monolayer to form a GaAs monolayer; and,
(e) repeating steps (a) through (d) until the desired thickness of stacked monolayers has been grown.
In another embodiment for the same purpose, the same step includes the steps of:
(a) first depositing sufficient atoms of Al to form an Al monolayer;
(b) then depositing sufficient atoms of Ga to form a Ga monolayer adjacent the Al monolayer;
(c) next depositing sufficient atoms of As to combine with the Al and Ga monolayers to form AlAs and GaAs monolayers; and,
(d) repeating steps (a) through (c) until the desired thickness of stacked monolayers has been grown.
In a third and preferred embodiment, the step includes the steps of:
(a) starting the simultaneous depositing of Al and Ga atom to form adjacent Al and Ga monolayers;
(b) stopping the depositing of Al when sufficient atoms of Al have been deposited to form the desired Al monolayer;
(c) stopping the depositing of Ga when sufficient atoms of Ga have been deposited to form the desired Ga monolayer;
(d) next depositing sufficient atoms of As to combine with the Al and Ga monolayers to form AlAs and GaAs monolayers; and,
(e) repeating steps (a) through (d) until the desired thickness of stacked monolayers have been grown.
The preferred method of the later embodiment additionally comprises between steps (c) and (d) thereof the step of delaying for a period of time sufficient to allow Al and Ga atom migration within each of the monolayers.
A preferred result is achieved where each step contains a plurality of atomic bonding sites on the surface thereof and the method additionally includes the step of establishing the time periods for deposition of the elements for each of the monolayers such that the total number of atoms of the elements deposited is equal in number to the number of the atomic bonding sites whereby a Coherent Superlattice (CSL) is formed.
In one version of the method, there are a pair of monolayer formed by a pair of elements A and B on each step and the method additionally comprises the step of making the width m of element A plus the width n of element B less than or equal to the width p of the step whereby the stacked monolayers form layers of elements A and B which are normal to the substrate.
In another version of the method, there are a pair of monolayer formed by a pair of elements A and B on each step and the method additionally comprises the step of making the width m of element A plus the width n of element B greater than the width p of the step whereby the stacked monolayers form layers of elements A and B which are tilted from being normal to the substrate thus forming a Coherent Tilted Superlattice (CTSL).
The method can create pseudo ternary semiconductor alloys as part of the CTSL by employing at least two binary compound semiconductor alloys in the deposition process. It can also create a quantum wire superlattice by sandwiching a thin tilted superlattice layer between two wider band gap layers. Additionally, it can create a tilted superlattice with misfit strain by using three binary compounds to produce a pseudo-ternary compound in a direction parallel to the substrate normal while the tilted superlattice structure provides a desired band gap in a direction parallel to the substrate surface. With respect to specific devices, one may form the CTSL as part of a field effect transistor (FET) wherein the CTSL is part of the FET gate or form the CTSL as the cladding layers of a quantum wire laser having a GaAs active layer.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified cutaway end view of a substrate prepared for the forming of a superlattice thereon according to the prior art.
FIG. 2 is a simplified drawing of the substrate of FIG. 1 in the process of forming a superlattice thereon according to the prior art during the deposition of a first material of a first layer.
FIG. 3 is a simplified drawing of the substrate of FIG. 1 in the process of forming a superlattice thereon according to the prior art during the deposition of a second material of a first layer.
FIG. 4 is a simplified drawing of the substrate of FIG. 1 after the process of forming a superlattice thereon according to the prior art depicting the multiple layers thereof.
FIG. 5 is an enlarged, simplified drawing of one step of a stepped substrate employed in the present invention during the process of forming a superlattice according to the methods of the present invention in a preferred embodiment depicting how the materials are simultaneously deposited randomly on the step.
FIG. 6 is a drawing depicting how the materials separate and migrate respectively to front and back sides of the step when practicing the preferred method of the present invention started in FIG. 5.
FIG. 7 is a simplified functional block diagram of apparatus for growing superlattice structures according to the various methods of the present invention.
FIG. 8 is a logic flowchart showing logic for incorporation into the system control logic of the apparatus of FIG. 7 for accomplishing one method of the present invention for growing AlAs/GaAs superlattice structures.
FIG. 9 is a timing diagram showing the control signals employed in the apparatus of FIG. 7 accomplished by the logic of FIG. 8.
FIG. 10 is a logic flowchart showing logic for incorporation into the system control logic of the apparatus of FIG. 7 for accomplishing another method of the present invention for growing AlAs/GaAs superlattice structures.
FIG. 11 is a timing diagram showing the control signals employed in the apparatus of FIG. 7 accomplished by the logic of FIG. 10.
FIG. 12 is a logic flowchart showing logic for incorporation into the system control logic of the apparatus of FIG. 7 for accomplishing the preferred method of the present invention for growing AlAs/GaAs superlattice structures.
FIG. 13 is a timing diagram showing the control signals employed in the apparatus of FIG. 7 accomplished by the logic of FIG. 12.
FIG. 14 is a simplified drawing of a tilted superlattice with two or three compounds according to the present invention.
FIG. 15 is a simplified drawing of a quantum well wire superlattice according to the present invention.
FIG. 16 is a simplified drawing of a coherent tilted superlattice according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The body of work upon which this invention is based uses III-V compound semiconductor material. As those skilled in the art will readily recognize and appreciate, however, the concept is general enough to be applied to other crystalline materials such as metals and ceramics. It is therefore the inventors' intent that the breadth accorded the disclosure that follows and the claims appended hereto be in keeping with the scope and spirit of the invention disclosed herein.
As mentioned above, this invention comprises further refinements and practical methods of production of a basic structural geometry disclosed and claimed in above-referenced U.S. Pat. No. 4,591,889, the teachings of which are incorporated herein by reference in the interest of simplicity and brevity and the avoidance of redundancy.
In working with superlattice structures and methods for their practical production starting from the limited teachings of the '889 patent, the inventors herein found and determined that the growth of tilted superlattices (with vertical superlattices merely being a special case thereof) involved the following:
(1) Use of a vicinal surface composed of a periodic array of steps. These surfaces can best be obtained by polishing a substrate a few degrees (0.5 to 4 degrees) off a major crystallographic {100}, {110}, or {111}. The substrate should be a single crystal and the surface steps should be monoatomic in height.
(2) The deposition of fraction of monolayers, m and n, of two semiconductors, A and B, with different composition and band gap. In the inventor's case, the primary materials employed were GaAs and Al x Ga 1-x As with 0<x<1. The fraction of monolayers m and n of the two semiconductors A and B should satisfy the conditions: m,n<1 with the tilt parameter, p=m+n˜1.
(3) The growth regime should be a layer growth mode and the layer nucleation should take place at step edges.
(4) All the fractional monolayers deposited should grow in phase; that is, all steps' motion during growth should move laterally with the same velocity.
The description which now follows describes the methods which the inventors herein have actually employed to satisfy the above-listed conditions and grow tilted superlattices such as those postulated by the '889 patent. Also described are novel extension of the tilted superlattice concept of the '889 patent for: the obtention of pseudo-ternary alloys out of binary compound semiconductors, the obtention of quantum wire superlattices, the growth of strained layers tilted superlattices, and the coherent tilted superlattice.
Before continuing with the details of the present invention, reference should be made to the enlarged, simplified drawings of FIGS. 5 and 6 to understand a physical phenomenon employed by the inventors in their preferred method of structural growth. For simplicity, only the activity at one step is shown. Also, it should be mentioned at this point that the description that follows concentrates on Molecular Beam Epitaxy (MBE) apparatus and methods of operation. As those skilled in the art will readily appreciate, the process to be described can be accomplished by other apparatus known in the art as well as apparatus under development or, perhaps, not even yet contemplated. One example would be Metal Organic Chemical Vapor Deposition (MOCVD) apparatus. The precise equipment employed should not be considered as a limiting factor of the present invention. MBE apparatus and methods are employed for disclosure purposes only because that is the equipment employed by the inventors herein in their experiments that lead to the present invention.
As depicted in FIG. 5, each preferred step 12 is monoatomic in thickness. If two materials (symbolized by the X's and O's) are deposited simultaneously in an amount to fill the step 12 with atoms of the two materials sufficient to form the two desired monolayers as depicted in FIG. 5, the atoms will migrate into the monolayers 26 and 28 in the manner depicted by the arrows in FIG. 6. This, of course, assumes the proper growing conditions of temperature and the like.
Turning now to FIG. 7, apparatus which can be employed for practicing the various methods of the present invention is depicted in simplified form therein. For convenience, simplicity, and the avoidance of unnecessary features which are not points of novelty to the present invention, aspects well known to those skilled in the art such as vacuum chambers, airlocks, and the like, have been omitted from the drawing. As is typical in such applications, there is a stage 30 for holding the stepped substrate 10 in place. There is a source 32 for creating an atomic beam 34 (or similar beam depending on the apparatus being used) containing the atoms of the materials to be grown on the substrate 10. As mentioned earlier, the source 32 can be MBE or MOCVD or Chemical Beam Epitaxy (CBE) apparatus, or any other appropriate equipment. The beam 34 is formed of materials (such as elements Al, As, Ga, etc., as appropriate) from the supply sources 36. The materials from the supply sources 36 pass through individually controllable apparatus such as shutters, valves, or the like, as appropriate to the particular apparatus being used to create the beam 34. For ease of representation only, this apparatus is represented by the control valves 38. The important aspect relative to the present invention is that each of the valves 38 controls the presence of one of the materials in the beam 34 and, additionally, the valves 38 are each individually connected to system control logic 40 to be controlled thereby. Thus, with respect to apparatus employed to practice the methods of the present invention, all of the materials to be used in the growth process must be controlled individually by the logic 40 according to logic steps now to be described.
In forming a layer of, for example, GaAs on a substrate in the prior art, it is common to direct a beam of Ga and As onto the substrate. As they form a molecular bond to the surface of the substrate, the Ga and As also bond to one another to form the desired GaAs. The inventors herein departed radically from that prior art approach to achieve their desired objectives. This is because of the behavioral phenomenon described earlier with respect to FIGS. 5 and 6. Thus, it was found to provide more desirable results if, for example, the Ga and Al were first applied to form the monolayers 26, 28 in an optimum manner and then the As was added. Since we are talking here about monoatomic layers, there is no potential problem of surface penetration to lower levels by the As there would be in a doping operation requiring much deeper penetration into a previously deposited material. The inventors found that there were, in fact, three ways to accomplish this approach and achieve their objectives with acceptable results. These three approaches will now be described with respect to possible logic to be included within the control logic 40 and the signals to be employed to regulate the composition of the beam 34.
The first approach is depicted in FIGS. 8 and 9. The logic 40 first opens the appropriate valve 38 to cause Al to be deposited on the steps 12 of the substrate 10 by the beam 34. The Al atoms nucleate adjacent the step edges 16 and bond to one another forming a monolayer 26 extending outward along the width of each step 12 from the edge 16 of the next higher step 12 in an amount determined by the quantity of Al deposited. As indicated by the decision blocks in FIG. 8, the logic 40 is pre-programmed in each case with the amount of time that Al, Ga, and As are to be deposited to achieve the desired structural geometry being created. After the Al of monolayer 26 is deposited, the Al source is turned off and the As source is opened for the time required to create the desired monolayer 26 of AlAs. This process is then repeated to form the monolayer 28 of GaAs adjacent the edge 20 of the first monolayer 26 by first depositing Ga for the proper time and then once again opening the source of As to deposit the proper amount of As. The logic 40 then tests to see if the preprogramed number of layers have been formed. If they have, the logic 40 exits. If not, it returns to the beginning of the loop to form another layer in the manner described above.
The second approach is shown in FIGS. 10 and 11. In this case, an Al monolayer 26 is formed followed by the formation of an adjacent Ga monolayer 28. Both the Al and Ga are then simultaneously bombarded with As atoms by the beam 34 to form the desired AlAs and GaAs at the same time.
The third and preferred approach is shown in FIGS. 12 and 13. This approach is based on the observed phenomenon of FIGS. 5 and 6. In the prior approaches, it should be realized and appreciated that the beam 34 only contained one material at a time. In this approach, the logic 40 starts by bombarding the substrate 10 with a combined atomic beam 34 containing both Al and Ga. The valve 38 for each is kept open for the pre-established time for that component and then closed. As the Al and Ga atoms arrive at the steps 12, they migrate, nucleate and bond in the manner shown in simplified form in FIGS. 5 and 6; thus, the Al forms its desired monolayer 26 adjacent the edge 16 of the next higher step 12 and the Ga forms its monolayer 28 adjacent the edge 20 of the Al. When the depositing of the Al and Ga is complete for a layer, the logic 40 then deposits the As in the manner described for the second approach above. Having thus described the methods and apparatus of the present invention in general and in simplified terms, the invention will be described in greater technical detail by reference to tested embodiments of the inventors herein.
The requirement of the existence of a periodic array of monoatomic surface steps was found by the inventors to be crucial to the success of this invention. In the methods and procedures developed by the inventors to achieve their objectives as reflected by functional blocks 42, 44 and 46 of FIG. 7 (i.e. substrate preparation, substrate analysis, and deposition analysis, respectively), the steps are introduced by carefully polishing a substrate by a few degrees from a major crystallographic plane. The misorientation direction is chosen to favor a direction which will result in step edges as straight as possible. In the case of MBE growth of GaAs and AlAs on a {001} GaAs substrate, this direction was found to be orthogonal to the {110} plane, i.e. the step edges are terminated by Arsenic dangling bonds since the chosen substrate is GaAs. The regularity of the step periodicity is found from analysis of the superlattice Reflection High Energy Electron Diffraction (RHEED) diffraction spots associated with the steps. The steps are rendered more periodic by depositing a GaAs buffer layer at a temperature corresponding to the disappearance of the RHEED oscillations. The straightness of the steps controls the interface roughness and is established by minimizing the kink density along the step edges. This is done by choosing the growth temperature that gives the narrowest RHEED spots for the beam direction parallel to the step edges. This temperature (˜610° C.) yields the narrowest and shortest step superlattice spots. The step period is adjusted by proper choice of the misorientation angle from a few tens to a few hundred angstroms (Å).
The fraction of monolayers of elements to be deposited are estimated with an accuracy of a few percent from the RHEED oscillations that are obtained during epitaxy of the elements being deposited. The RHEED oscillations give the times, t1 and t2, taken for the deposition of a monolayer of each of two elements. The times required for deposition of m and n fractional monolayers are taken as mt1 and nt2. These, of course, are the parameters used to pre-establish the times employed in the logic 40 as described above.
A layer growth mode is insured by growing at a sufficiently high temperature, T C , to allow fast migration of the atoms to the nearest nucleation sites, i.e. the step edges. The rapid atom migration required is achieved by depositing in the Atomic Layer Epitaxial (ALE) mode. In this mode, the deposition of Al and Ga, for example, is taking place while the As shutter of the MBE system is closed. Note that an additional time (0.3 second in tested embodiments) for Al and Ga atom migration is also allowed after each deposition cycle before opening the As shutter. While not shown in the simplified logic flowcharts of FIGS. 8, 10 and 12, this delay between the deposition cycles should be included in a preferred implementation of the present invention. At the temperature T C , the RHEED oscillations should also disappear. This necessary condition establishes that all step edges are moving in phase during growth. The inventors found this optimal temperature (T C ) to be ˜625° C. in their MBE system.
EXTENSIONS OF THE SUPERLATTICE CONCEPTS OF 2D CRYSTAL ARCHITECTURE AND STRAIN LAYER TILTED SUPERLATTICES
As mentioned earlier herein, in developing their novel methods and apparatus to successfully implement the basic superlattice concepts of the '899 patent beyond the "paper patent" state, the inventors also developed several new and novel superlattices. Those will now be described.
1. Growth of ternary compound semiconductor tilted superlattices
In a first instance, it was the inventors' intent to create pseudo ternary semiconductor alloys out of the deposition of two binary compound semiconductor alloys using the concept of the tilted superlattice deposition. This is illustrated in FIG. 14. In the simple case of half monolayer deposition of elements A and B, the deposition sequence ABABABAB . . . will yield the standard tilted superlattice of the '899 patent. The deposition sequence ABAAABAAAB . . . will yield the (AB ternary, A binary) structure shown in FIG. 14 (replace C by A in this Figure to visualize this structure). The concept is easily extended to the deposition of more complex ternary materials from the deposition of fractional monolayers of three ternary elements A, B, and C. The deposition sequences can result in AC-B or AC-BC or AC-AB tilted superlattices with the appropriate sequences. The inventors have experimentally demonstrated this concept with the deposition of GaAs-AlAs half monolayers and found that a Ga 0 .5 Al 0 ,5 As-GaAs tilted superlattice could be produced in this manner. For example, employing the deposition sequence ABAAABAAAB . . . will yield an AB ternary, A binary structure; employing the deposition sequence ABCBABCBABC . . . yields an AC ternary, B binary structure; employing the deposition sequence ABAAABAAAB . . . yields an AB ternary, A binary structure; employing the deposition sequence ABCCABCCABC . . . yields an AC ternary, BC binary structure; employing the deposition sequence ABCAABCAABC . . . yields an AC ternary, AB binary structure; and employing the deposition sequence ABAAABAAAB . . . yields an AB ternary, A binary structure.
2. Growth of quantum wire superlattices with 2D carrier confinements
While the forming of quantum wire-containing superlattices was postulated in the '889 patent and are depicted in FIG. 5 thereof, the inventors herein have built and tested a quantum wire superlattice having the geometry illustrated in FIG. 15 hereof which is practical and patentably distinct over the never-built conceptual design of the '889 patent. Specifically, the inventors herein found that a practical quantum wire superlattice could be grown directly by sandwiching a thin tilted superlattice (TSL) layer between two wider band gap layers of AlAs as illustrated in FIG. 15. Such structures have been built and tested by the inventors and have demonstrated unique quantum wire effects associated with 2 dimensional carrier confinement.
3. Tilted superlattices with misfit strain
As is well known in the art, lattice mismatch and thermal differential expansion between the epitaxial layers and the substrate have been a main obstacle to the use of a wide variety of compound semiconductors. In other words, while the desired geometries can be created, they tend to self-destruct because of different thermal expansion qualities of the compounds employed causing the epitaxial layers to delaminate and separate from the substrate. In fact, the need for low defect densities of the epitaxial layers actually limits their choice to a few lattice matched substrate materials. One is then forced to use quaternary compounds to achieve both lattice matching conditions and the desired band gap for the epitaxial layer. TSLs offer a potentially important alternative solution to this problem. As illustrated in FIG. 14, the use of three binary compounds allows one to produce a pseudo-ternary compound in a direction parallel to the substrate normal, while a TSL produces the desired band gap in a direction parallel to the substrate surface. For example, the layer,
--(A).sub.m (B).sub.n (C).sub.m (B).sub.n --
may be viewed as a TSL of the type (AC)m-(B)n if m+n˜1. Its lattice parameters aAC and aB are those of the pseudo ternary alloy AC and of a binary alloy B. The misfit strain, in the simple case corresponding to m+n+1 is: ##EQU1## where a s is the substrate lattice parameter.
Lattice matching conditions may be achieved by adjusting m and/or n if the AC layers are in compression and the B layer is in tension. The case of an InP substrate with layers of InGaAs or InAs and GaAs could satisfy the above equation with a zero misfit strain for a range of effective band gaps of the InGaAs quantum well layers. Exact lattice matching conditions exist for: ##EQU2## and a AC >a S >a B . The TSL effective band gap may be adjusted by choosing the substrate tilt angle while maintaining a zero misfit strain in the structure. The width of the quantum well is given by: ##EQU3## where α is the tilt angle.
It should also be noted here that in this case, the substrate will be unstrained at all times and thus the island nucleation regime could be avoided more easily than in the growth of conventional strained layer superlattices.
4. Naturally grown tilted superlattices of coherent tilted superlattices
The inventors herein have realized tilted and vertical superlattices in a completely novel way, as described above, by co-deposition of Al and Ga on a vicinal surface (misoriented by 1° or 2° from the main {100} crystallographic orientation. Specifically, they have achieved a tilted superlattice by growing under the following conditions.
(a) The number of Al and Ga atoms deposited with the Arsenic flux "off" should be equal to the number of surface lattice sites. For this reason, the inventors choose to call this type of tilted superlattice a Coherent Tilted Superlattice (CTSL).
(b) The growth temperature should be above the critical temperature which corresponds to the disappearance of RHEED oscillations (˜610° C.).
(c) The Al and Ga co-deposition should be taking place with the As flux shut off from the substrate.
The inventors have found that the tilt of the Tilted Superlattice will be controlled by the tilt parameter p. In the case of the naturally grown CTSL, the tilt parameter corresponds to p=m+n, where m and n are the fraction of Al and Ga monolayers co-deposited during each cycle. This new mode of deposition which permits the deposition of naturally tilted superlattices has been designated by the inventors as CTSL deposition. CTSL deposition requires that the number of atoms deposited per cycle is equal to the number of surface sites. In addition, it requires a surface with a monoatomic periodic step array.
5. Device implications
With the Tilted Superlattice and the Coherent Tilted Superlattice, the inventors herein have provided two means of modulating the materials' band gap in a direction parallel to the surface. With a CTSL in which doping has been introduced as shown in FIG. 16, one can introduce a modulation of the conductivity in a 2 dimensional electron gas by imposing additional carrier confinement with the CTSL in a direction normal to the figure. This will allow the building of a one dimensional electron gas at the GaAs-CTSL interface. Field effect transistors (FETs) build with this type of structure are expected to exhibit superior characteristics (transconductance) and perform as very high mobility devices. The CTSL should be part of the FET gate while the source and drain should be along the direction perpendicular to the figure.
The CTSL can also be used to advantage as a way of fabricating a quantum wire laser. These types of lasers are expected to exhibit low threshold currents. The active layer of these layers will be a GaAs quantum well while the cladding barrier layers will be composed of a CTSL.
Note that the CTSL deposition as described above demonstrates the possibility of producing a self-organizing system with semiconductor alloys. The period of the CTSL is adjusted either with the alloy composition or the substrate tilt angle. This self-organizing system may be realized with a number of semiconductor alloys (e.g., In, GaAs, InSb, Ga) and metal alloys. The central requirement to produce the CTSL form of a self-organizing system is the presence of a periodic array of monoatomic steps. | A method for growing a superlattice structure on a substrate. First, a periodic array of monoatomic surface steps are created on the surface of the substrate at an area to have the superlattice structure grown thereon. There is apparatus for creating a beam of a material being input thereto and for selectively including or not including respective ones of a plurality of materials within the beam. The beam is directed at the steps of the substrate. Finally, logic causes control apparatus to include and not include respective ones of the materials within the beam in a pre-established pattern of time periods which will cause the materials to be deposited on the steps in a series of stacked monolayers. Tilted Superlattices (TSLs) and Coherent Tilted Superlattices (CTSLs) are created. The method can create pseudo ternary semiconductor alloys as part of a CTSL by employing at least two binary compound semiconductor alloys in the deposition process. It can also create a quantum wire superlattice by sandwiching a thin CTSL layer between two wider band gap layers. Additionally, it can create a tilted superlattice with zero misfit strain by using three binary compounds to produce a pseudo-ternary compound in a direction parallel to the substrate normal while the tilted superlattice structure provides a desired band gap in a direction parallel to the substrate surface. One may form the CTSL as part of a field effect transistor (FET) wherein the CTSL is part of the FET gate or form the CTSL as the cladding layers of a quantum wire laser having a GaAs active layer. | 8 |
This application is a division of application Ser. No. 10/042,164, filed Jan. 11, 2002, now U.S. Pat. No. 6,569,470, which is a division of Ser. No. 09/325,852, filed Jun. 4, 1999, now U.S. Pat. No. 6,350,479, which claims priority under 35 U.S.C. § 119(e) to Provisional Application No. 60/088,117, filed Jun. 5, 1998.
FIELD OF THE INVENTION
The present invention relates to the novel use of compounds and substances which are capable of modulating monoamine oxidase (MAO) activity by inhibiting the MAO enzyme. The present invention also relates to MAO inhibitors and their therapeutic use as a drug or dietary supplement in the treatment of various conditions or disorders, including psychiatric and neurological illnesses. More particularly, the present invention relates to the therapeutic use of tobacco alkaloids, Yerbamaté ( Ilex paraguariensis ) extract, or tobacco extracts to inhibit MAO activity to provide a treatment for various disorders or conditions.
BACKGROUND OF THE INVENTION
By inhibiting MAO activity, MAO inhibitors can regulate the level of monoamines and their neurotransmitter release in different brain regions and in the body (including dopamine, norepinephrine, and serotonin). Thus, MAO inhibitors can affect the modulation of neuroendocrine function, respiration, mood, motor control and function, focus and attention, concentration, memory and cognition, and the mechanisms of substance abuse. Inhibitors of MAO have been demonstrated to have effects on attention, cognition, appetite, substance abuse, memory, cardiovascular function, extrapyramidal function, pain and gastrointestinal motility and function. The distribution of MAO in the brain is widespread and includes the basal ganglia, cerebral cortex, limbic system, and mid and hind-brain nuclei. In the peripheral tissue, the distribution includes muscle, the gastrointestinal tract, the cardiovascular system, autonomic ganglia, the liver, and the endocrinic system. The present invention overcomes the problems and limitations of the prior art by providing methods and systems.
MAO inhibition by other inhibitors have been shown to increase monoamine content in the brain and body. Regulation of monoamine levels in the body have been shown to be effective in numerous disease states including depression, anxiety, stress disorders, diseases associated with memory function, neuroendocrine problems, cardiac dysfunction, gastrointestinal disturbances, eating disorders, hypertension, Parkinson's disease, memory disturbances, and withdrawal symptoms.
It has been suggested that cigarette smoke may have irreversible inhibitory effect towards monoamine oxidase (MAO). A. A. Boulton, P. H. Yu and K. F. Tipton, “Biogenic Amine Adducts, Monoamine Oxidase Inhibitors, and Smoking,” Lancet, 1(8577): 114-155 (Jan. 16, 1988), reported that the MAO-inhibiting properties of cigarette smoke may help to explain the protective action of smoking against Parkinson's disease and also observed that patients with mental disorders who smoke heavily do not experience unusual rates of smoking-induced disorders. It was suggested that smoking, as an MAO inhibitor, may protect against dopaminergic neurotoxicity that leads to Parkinson's disease and that the MAO-inhibiting properties of smoking may result in an anti-depressive effect in mental patients.
L. A. Carr and J. K. Basham, “Effects of Tobacco Smoke Constituents on MPTP Induced Toxicity and Monoamine Oxidase Activity in the Mouse Brain,” Life Sciences, 48:1173-1177 (Jan. 16, 1991), found that nicotine, 4-phenylpyridine and hydrazine prevented the decrease in dopamine metabolite levels induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in mice, but there was no significant effect on dopamine levels. Because tobacco smoke particulate matter caused a marked inhibition of MAO A and MAO B activity when added in vitro, it was suggested that one or more unidentified substances in tobacco smoke are capable of inhibiting brain MAO and perhaps altering the formation of the active metabolite of MPTP.
J. S. Fowler, N. D. Volkow, G. J. Wang, N. Pappas, and J. Logan, “Inhibition of Monoamine Oxidase B in the Brain of Smokers,” Nature (Lond), 379(6567):733-736 (Feb. 22, 1996), found that the brains of living smokers showed a 40% decrease in the level of MAO B relative to non-smokers or former smokers. MAO inhibition was also reported as being associated with decreased production of hydrogen peroxide.
It has also been suggested that nicotine may not be the only constituent of tobacco responsible for tobacco addiction. J. Stephenson, “Clues Found to Tobacco Addiction,” Journal of the American Medical Association, 275(16): 1217-1218 (Apr. 24, 1996), discussing the work of Fowler, et al., pointed out that the brains of living smokers had less MAO B compared with the brains of nonsmokers or former smokers. MAO B is an enzyme involved in the breakdown of dopamine, which is a pleasure-enhancing neurotransmitter. The results suggested that the inhibition of MAO B in the brains of smokers may make nicotine more addictive by slowing down the breakdown of dopamine, thereby boosting its levels. The findings provided an explanation as to why cigarette smokers were less susceptible to developing Parkinson's disease. Further, the findings suggested that MAO inhibitors could be used for smoking cessation.
K. R. R. Krishnan, “Monoamine Oxidase Inhibitors,” The American Psychiatric Press Textbook of Pharmacology, American Psychiatric Press, Inc., Washington, D.C. 1995, pp. 183-193, suggest various uses for monoamine oxidase inhibitors. The uses include atypical depression, major depression, dysthymia, melancholia, panic disorder, bulimia, atypical facial pain, anergic depression, treatment-resistant depression, Parkinson's disease, obsessive-compulsive disorder, narcolepsy, headache, chronic pain syndrome, and generalized anxiety disorder.
D. Nutt and S. A. Montgomery, “Moclobemide in the Treatment of Social Phobia,” Int. Clin. Psychopharmacol, 11 Suppl. 3: 77-82 (Jun. 11, 1996), reported that moclobemide, a reversible MAO inhibitor, may be effective in the treatment of social phobia.
I. Berlin, et al., “A Reversible Monoamine Oxidase A Inhibitor (Moclobemide) Facilitates Smoking Cessation and Abstinence in Heavy, Dependent Smokers,” Clin. Pharmacol. Ther., 58(4): 444-452 (October 1995), suggested that a reversible MAO A inhibitor can be used to facilitate smoking cessation.
U.S. Pat. No. 3,870,794 discloses the administering of small quantities of nicotine and nicotine derivatives to mammals, including humans, to reduce anger and aggressiveness and to improve task performance.
U.S. Pat. No. 5,276,043 discloses the administering of an effective amount of certain anabasine compounds, certain unsaturated anabasine compounds, or unsaturated nicotine compounds to treat neurodegenerative diseases.
U.S. Pat. No. 5,516,785 disclose a method of using anabasine, and DMAB anabasine for stimulating brain cholinergic transmission and a method for making anabasine.
U.S. Pat. Nos. 5,594,011, 5,703,100, 5,705,512, and 5,723,477 disclose modulators of acetylcholine receptors.
Known irreversible MAO inhibitors also inhibit MAO in the stomach and liver as well as the brain. As a result, their use has been limited because hypertensive crisis may occur when certain types of food (for example, fermented foods) are ingested, thereby creating an adverse drug-food interaction. Tyramine, which has a pressor action and which is normally broken down by the MAO enzymes, can be present in certain foods.
Thus, it would be desirable to provide MAO inhibitors which are effective, but less potent (i.e., those which provide an asymptotic effect on MAO inhibition) than known MAO inhibitors, for the treatment-of various conditions and disorders. It would also be desirable to provide MAO inhibitors which are easily synthesized and which could be provided to patients as an “over the counter” medication or dietary supplement.
BRIEF SUMMARY OF THE INVENTION
The present invention relates to the discovery that certain tobacco alkaloids or extracts, a certain tea plant extract, and a certain extract of tobacco extract-containing chewing gum and lozenges provide MAO-inhibiting effects. The present invention also relates to the use of these compounds or substances in the treatment of certain conditions and disorders in mammals, including humans.
The compounds and substances of the present invention are capable of inhibiting MAO activity in mammalian brain and peripheral tissue. These compounds and substances act by increasing the concentration of monoamine compounds (norepinephrine, dopamine, and serotonin) in the body and brain.
The present invention provides a method of treating certain medical, psychiatric and/or neurological conditions or disorders. In a first embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of anabasine, anatabine or nornicotine to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
In a second embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of an extract of Yerbamaté ( Ilex paraguariensis ) tea plant to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
In a third embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of a tobacco extract to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
In a fourth embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of an extract of gum and lozenges formulated with tobacco extract to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a plot of MAO inhibition versus time for anabasine.
FIG. 2 shows the inhibition of MAO A and MAO B for anabasine.
FIG. 3 shows a plot of MAO inhibition versus time for anatabine.
FIG. 4 shows the inhibition of MAO A and MAO B for anatabine.
FIG. 5 shows a plot of MAO inhibition versus time for nornicotine.
FIG. 6 shows the inhibition of MAO A and MAO B for nornicotine.
FIG. 7 shows a plot of MAO inhibition versus time for Yerbamaté.
FIG. 8 shows the inhibition of MAO A and MAO B for Yerbamaté.
FIG. 9 shows a plot of MAO inhibition versus time for tobacco extract.
FIG. 10 shows the inhibition of MAO A and MAO B for tobacco extract.
FIG. 11 shows a plot of MAO inhibition versus time for GUMSMOKE.
FIG. 12 shows a plot of MAO inhibition versus time for a lozenge extract.
DETAILED DESCRIPTION OF THE INVENTION
MAO is an important enzyme that plays a major role in the metabolic transformation of catecholamines and serotonin. Neurotransmitters from this group are metabolized by MAO, and thus their effect is decreased at their receptor cites. MAO is important for the regulation of the levels of dopamine, norepinephrine and serotonin.
Accordingly, inhibition of this major enzyme system will have major effects on the functions regulated by this compound.
In a first embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of anabasine, anatabine or nornicotine to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
Anabasine, anatabine and nornicotine are minor tobacco alkaloids. These compounds are commercially available. However, they may be synthesized according to known techniques or extracted directly from tobacco itself.
Preferably, anatabine is synthesized according to the method disclosed by N. M. Deo and P. A. Crooks, “Regioselective Alkylation of N-(diphenylmethylidine)-3-(aminomethylpyridine: A Simple Route to Minor Tobacco Alkaloids and Related Compounds,” 1137-1141 (11 Dec. 1995), which is incorporated herein by reference.
In addition, nornicotine is preferably synthesized according to the method disclosed by S. Brandange and L. Lindblom, “N-Vinyl as N-H Protecting Group: A Convenient Synthesis of Myosmine,” Acta Chem. Scand., B30, No. 1, p. 93 (1976), which is also incorporated herein by reference.
In a second embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of an extract of Yerbamaté ( Ilex paraguariensis ) tea plant to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
The Yerbamaté extract may be prepared by shredding the Yerbamaté materials, mixing the shredded materials with a water/ethanol (for example, 1/1 by volume) solution in a mixture of about four leaves per 10 ml of the water/ethanol mixture, extracting with continuous stirring, and then removing the solution from the Yerbamaté residue. The residue can then be further extracted two more times with the same volume of water/ethanol mixture, and then the extracts may be combined and filtered to remove the particulate Yerbamaté materials. The combined extracts may then be subject to vacuum evaporation to yield the Yerbamaté extract.
In a third embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of a tobacco extract to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
The tobacco extract may be prepared by shredding tobacco leaves (for example, processed tobacco obtained from STAR TOBACCO, INC.), mixing the shredded leaves with a water/ethanol (for example, 1/1 by volume) solution in a mixture of about four leaves per 10 ml of the water/ethanol mixture, extracting with continuous stirring, and then removing the solution from the tobacco residue. The residue can then be further extracted two more times with the same volume of water/ethanol mixture, and then the extracts may be combined and filtered to remove the particulate tobacco leaf material. The combined extracts may then be subject to vacuum evaporation to yield the tobacco extract.
In a fourth embodiment of the invention, the method comprises administering a MAO-inhibiting effective amount of an extract of chewing gum and lozenges formulated with tobacco extract to a mammal, particularly a human, for the treatment of medical, psychiatric and/or neurological conditions and disorders such as, but not limited to, Alzheimer's disease, Parkinson's disease, major depression, minor depression, atypical depression, dysthymia, attention deficit disorder, hyperactivity, conduct disorder, narcolepsy, social phobia, obsessive-compulsive disorder, atypical facial pain, eating disorders, drug withdrawal syndromes and drug dependence disorders, including dependence from alcohol, opioids, amphetamines, cocaine, tobacco, and cannabis (marijuana), melancholia, panic disorder, bulimia, anergic depression, treatment-resistant depression, headache, chronic pain syndrome, generalized anxiety disorder, and other conditions in which alteration of MAO activity could be of therapeutic value.
The chewing gum and lozenges extract may be prepared by extracting five slices of GUMSMOKE chewing gum and NICOMINT lozenges (obtained from STAR TOBACCO, INC.), which are formulated with tobacco extract, with distilled water (50 ml) at room temperature for 12 hours, and then removing the undissolved gum substance by filtration.
The above compounds and substances were evaluated for their MAO inhibiting activity. Test results surprisingly showed that the compounds and substances of the present invention all provided MAO inhibition. It was also discovered that the MAO inhibiting effects had a different character than for known MAO inhibitors in that they reached an asymptotic or ceiling effect, so that further increases in the dose beyond maximal inhibition did not produce any further increase in the MAO inhibition. This asymptotic effect would provide many benefits. For example, the problems associated with previously known, irreversible MAO inhibitors, such as hypertensive effects, can be avoided. Furthermore, the inventive MAO inhibitors may be provided as an “over the counter” drug or dietary supplement in view of its safety and efficacy.
The MAO inhibitors of the present invention may be provided in forms well known to one skilled in the art. They may be formulated in a pharmaceutically acceptable carrier, diluent or vehicle and administered in effective amounts. They may be provided in the form of a capsule, pill, tablets, lozenge, gum, troches, suppositories, powder packets or the like.
The determination of the effective amounts for a given treatment can be accomplished by routine experimentation and is also well within the ordinary skill in the art.
EXAMPLES
To determine the effectiveness of compounds and substances of the present invention, experiments were conducted as follows:
MAO Reaction:
The MAO activities of the compounds and substances were determined using standard reaction conditions as described in Halt, A., et al., Analytical Biochemistry, 244:384-392 (1997).
Tissue Preparation:
Liver samples from cow or rat were obtained immediately after sacrifice. Liver was homogenized in a Polytron mechanical homogenizer in a ratio of 1 gram of liver to 1 ml of potassium phosphate buffer (0.2 M at pH of 7.6). Large membranes were removed by low speed centrifugation at 1000×g for 15 minutes. The supernatant was removed from the pellet and used immediately for MAO activity assays or stored at 0 degrees Centigrade. Protein levels were determined in the liver homogenate by the Bradford protein reaction.
Reaction Conditions:
The standard reaction conditions were developed as a modification of the spectrophotometric assay using standard conditions (Halt, A., et al., Analytical Biochemistry, 244:384-392 (1997)). Total MAO activity was determined by incubating the liver preparations for 30 minutes at 37 degrees Centigrade with a 1/1 dilution of a test fraction (compound or substance to be tested dissolved in distilled water) or control condition (water alone). This incubation allowed the test compound or substance to interact with the enzyme under physiological conditions. The final tissue concentration in the reaction mixture was 3.5 mg per 100 ml.
Following the incubation with test compounds/substances or control, the MAO reactions were initiated and the reactions were incubated at 37 degrees Centigrade. The reaction was initiated by mixing 150 μl of preincubated tissue with 150 μl of chromogenic solution (containing 10 mM vanillic acid, 5 mM 4-amino antipyrene, 20 units/ml of peroxidase in 0.2 M potassium phosphate buffer final concentration pH 7.6), 600 μl of amine substrate (tyramine 500 micromolar), and 100 μl of distilled water (1 ml reaction volume). The standard reaction time was for 1 hour, but reaction times varied from 1 minute to 3 hours to evaluate the time course of the reaction in the presence or absence of test substance or control. The reactions were terminated by the addition of 30 μl of a stop solution of phenelzine (10 mM). The stopped reactions were stored on ice and placed at room temperature for reading in a spectrophotometer at a wavelength of 498 nm. The resulting values were analyzed to determine the amount of reaction product produced by MAO activity. This assay was reliable and simple to perform. A standard curve using hydrogen peroxide for enzyme activity was prepared for each experiment to determine the activity of the enzyme.
Selective assays of MAO A and MAO B isoforms were determined by using selective inhibitors of each of these enzymes. During the preincubation of the enzyme with the test solutions, either pargyline or chlorgyline (final drug concentrations in the reaction mixture of 500 AM) was added to the reaction mixture. This technique allowed for the assay of MAO A or MAO B activity in the absence of the activity of the other isoform of the enzyme. All other reaction conditions were conducted as for total MAO activity studies.
Each of the compounds and substances of the present invention were evaluated by initially determining a concentration curve at a reaction time of one hour. After determining the concentration curves of each compound or substance on MAO activity, a reaction time course in the presence or absence of test compound or substance was determined and time course curves were generated. Following these experiments, the effect of each test compound or substance was evaluated on MAO A and MAO B activity by the same reaction studies as described above for the total enzyme activity.
Example 1
Anabasine, in its purified form, was dissolved in distilled water in a maximal inhibition concentration of 0.2 mg/ml, and tested according to the procedure described above. At maximal or saturating inhibition concentrations, anabasine was effective at inhibiting MAO activity by approximately 10-13%, and was effective at inhibiting the enzyme at all time points in the reaction.
FIG. 1 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of anabasine over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 5 determinations. All the data points shown in FIG. 1 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.01), and were representative of multiple experiments.
Since anabasine was an inhibitor of MAO activity, further studies were conducted to evaluate if this agent was inhibiting MAO A or B activity using the methods described above. Anabasine was found to inhibit both MAO A and MAO B activity as shown in FIG. 2 . FIG. 2 presents the means (plus or minus the standard errors of the means) for 5 determinations for the percent inhibition of MAO A and MAO B activity. The effects of anabasine on both forms of MAO activity were statistically, significantly different from control enzyme conditions (student t test, p<0.05). The results demonstrate that anabasine inhibits both MAO A and B forms of the enzyme.
Example 2
Anatabine in its purified form, was dissolved in distilled water in a maximal inhibition concentration of 0.1 mg/ml, and tested according to the procedure described above. At maximal or saturating inhibition concentrations, anatabine was effective at inhibiting MAO activity by approximately 60%. This result shows that anatabine may be much safer as a medication than standard MAO enzyme inhibitors. Anatabine was effective at inhibiting the enzyme at all time points in the reaction, and was equally effective in inhibiting both MAO A and MAO B activities.
FIG. 3 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of anatabine over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 6 determinations. Anatabine was an effective MAO inhibitor at maximal concentrations, inhibiting the enzyme by approximately 60%, as discussed above. All the data points shown in FIG. 3 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.005) and were representative of multiple experiments.
Since anatabine was an inhibitor of MAO activity, further studies were conducted to evaluate if this agent was inhibiting MAO A or B activity using the methods described above. Anatabine was found to inhibit both MAO A and MAO B activity as shown in FIG. 4 . FIG. 4 presents the means (plus or minus the standard errors of the means) for 6 determinations for the percent inhibition of MAO A and MAO B activity. The effects of anatabine on both forms of MAO activity were statistically, significantly different from control enzyme conditions (student t test, p<0.01). The results demonstrate that anatabine inhibits both MAO A and -B forms of the enzyme.
Example 3
Nornicotine in its purified form, was dissolved in distilled water in a maximal inhibition concentration of 0.08 mg/ml, and tested according to the procedure described above. At maximal or saturating inhibition concentrations, nornicotine was effective at inhibiting MAO activity by approximately 80 to 95%, and was effective at inhibiting the enzyme at all time points in the reaction. Nornicotine was also equally effective in inhibiting both MAO A and MAO B activities.
FIG. 5 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of nornicotine over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 6 determinations. Nornicotine was an effective MAO inhibitor at maximal concentrations, inhibiting the enzyme by approximately 80-95%, as discussed above. All the data points shown in FIG. 5 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.01) and were representative of multiple experiments.
Since nornicotine was an inhibitor of MAO activity, further studies were conducted to evaluate if this agent was inhibiting MAO A or B activity using the methods described above. Nornicotine was found to inhibit both MAO A and MAO B activity as shown in FIG. 6 . FIG. 6 presents the means (plus or minus the standard errors of the means) for 6 determinations for the percent inhibition of MAO A and MAO B activity.
The effects of nornicotine on both forms of MAO activity were statistically, significantly different from control enzyme conditions (student t test, p<0.01). The results demonstrate that nornicotine inhibits both MAO A and B forms of the enzyme.
Example 4
The Yerbamaté extract was prepared as follows: Yerbamaté materials (obtained from STAR TOBACCO, INC.) were shredded and mixed with a water/ethanol (1/1 by volume) solution in a mixture of about four leaves per 10 ml of the water/ethanol mixture; the materials were then extracted overnight with continuous stirring; the solution was then removed from the Yerbamaté residue and stored; the residue was then further extracted overnight two more times with the same volume of water/ethanol mixture, and the three extracts were combined and filtered to remove the particulate Yerbamaté material; and the combined extracts were subjected to removal of the water/ethanol by vacuum evaporation. The resultant extract was then weighed and solubilized in distilled water.
When tested, Yerbamaté extract was effective in inhibiting MAO activity. The maximal inhibition concentration was 10 mg/ml. At maximal or saturating inhibition concentrations, the Yerbamaté extract inhibited MAO activity by approximately 40 to 50%. The results suggest that Yerbamaté may be much safer as a medication than standard MAO enzyme inhibitors. The extract was effective in inhibiting MAO at all time points in the reaction, and was equally effective in inhibiting both MAO A and MAO B activities.
FIG. 7 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of Yerbamaté over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 5 determinations. Yerbamaté was an effective MAO inhibitor at maximal concentrations, inhibiting the enzyme by approximately 40-50%, as discussed above. All the data points shown in FIG. 7 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.005) and were representative of multiple experiments.
Since Yerbamaté was an inhibitor of MAO activity, further studies were conducted to evaluate if this agent was inhibiting MAO A or B activity using the methods described above: Yerbamaté was found to inhibit both MAO A and MAO B activity as shown in FIG. 8 . FIG. 8 presents the means (plus or minus the standard errors of the means) for 5 determinations for the percent inhibition of MAO A and MAO B activity.
The effects of Yerbamaté on both forms of MAO activity were statistically, significantly different from control enzyme conditions (student t test, p<0.01). The results demonstrate that Yerbamaté inhibits both MAO A and B forms of the enzyme.
Example 5
The tobacco extract was prepared in the same manner as in Example 4, except that processed tobacco leaves (obtained from STAR TOBACCO, INC.) were substituted for the Yerbamaté materials.
When tested, the tobacco extract was effective in inhibiting MAO activity. At maximal or saturating inhibition concentrations, the tobacco extract was able to inhibit MAO activity by approximately 60%. The results suggest that the extract may be much safer as a medication than standard MAO enzyme inhibitors. The tobacco extract was effective at inhibiting MAO at all time points in the reaction, and was equally effective in inhibiting both MAO A and MAO B activities.
FIG. 9 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of tobacco extract over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 8 determinations. Tobacco extract was an effective MAO inhibitor at maximal concentrations, inhibiting the enzyme by approximately 60%, as described above. All the data points shown in FIG. 9 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.001) and were representative of multiple experiments.
Since tobacco extract was an inhibitor of MAO activity, further studies were conducted to evaluate if this agent was inhibiting MAO A or B activity using the methods described above. Tobacco extract was found to inhibit both MAO A and MAO B activity as shown in FIG. 10 . FIG. 10 presents the means (plus or minus the standard errors of the means) for 8 determinations for the percent inhibition of MAO A and MAO B activity. The effects of tobacco extract on both forms of MAO activity were statistically, significantly different from control enzyme conditions (student t test, p<0.005). The results demonstrate that tobacco extract inhibits both MAO A and B forms of the enzyme.
Examples 6 and 7
The extract of GUMSMOKE chewing gum or lozenges was prepared as follows: five slices each of gum or lozenges, formulated with tobacco extract, were extracted with 50 ml of distilled water at room temperature for 12 hours. The undissolved gum substance was removed by filtration. (The lozenges dissolved completely.) Dilutions of these extracts were prepared for evaluation.
The gum and lozenges extracts were effective in inhibiting MAO activity. At maximal or saturating concentrations, the extracts were able to inhibit MAO activity by approximately 50 to 60%.
FIG. 11 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of an extract of GUMSMOKE chewing gum prepared as described above over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 4 determinations. GUMSMOKE extract was an effective MAO inhibitor at maximal concentrations, inhibiting the enzyme by approximately 50-60%. All the data points shown in FIG. 11 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.05) and were representative of multiple experiments.
FIG. 12 presents the means (plus or minus the standard errors of the means) for the percent inhibition of MAO activity produced by saturating concentrations of an extract of the lozenge prepared as described above over 60 minutes of MAO activity measured as described above. Each data point represented the mean of 4 determinations.
The lozenge extract was an effective MAO inhibitor at maximal concentrations, inhibiting the enzyme by approximately 50-60%. All the data points shown in FIG. 12 were statistically, significantly different from the sham control at each time point tested (student t test, p<0.05) and were representative of multiple experiments. Both MAO A and MAO B were also inhibited by these extracts. | The present invention provides a group of tobacco alkaloids, tobacco extract, Yerbamaté extract, and an extract of chewing gum and lozenges which are modulators of monoamine oxidase (MAO) activity (i.e., compounds and substances which inhibit MAO enzyme and prevent its biological activity). The MAO inhibitors of the present invention can cause an increase in the level of norepinephrine, dopamine, and serotonin in the brain and other tissues, and thus can cause a wide variety of pharmacological effects mediated by their effects on these compounds. The MAO inhibitors of the present invention are useful for a variety of therapeutic applications, such as the treatment of depression, disorders of attention and focus, mood and emotional disorders, Parkinson's disease, extrapyramidal disorders, hypertension, substance abuse, smoking substitution, anti-depression therapy, eating disorders, withdrawal syndromes, and the cessation of smoking. | 0 |
[0001] This application claims the benefit of U.S. Patent Application Serial No. 60/210,252, filed Jun. 8, 2000, which is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to the use of aldehyde donors, such as 1,3-bis(hydroxymethyl)-5,5-dimethylhydantoin, to stabilize peroxides in aqueous solutions and in particular circulating water slurries in papermaking applications.
BACKGROUND OF THE INVENTION
[0003] The bleaching of wood fibers frequently involves the use of peroxides, such as hydrogen peroxide. Hydrogen peroxide, however, is readily decomposed by catalase, an enzyme often found in recycled water (i.e. water from processing recycled paper). Most aerobic bacteria synthesize peroxide-degrading enzymes (e.g. catalase and peroxidase) as a defense against free-radical-producing peroxides that are formed during cell respiration. In a mill white water environment, temperatures and the availability of nutrients encourage bacterial growth. The presence of hydrogen peroxide stimulates bacteria to generate catalase to destroy it, sometimes enough to hamper or disable a hydrogen peroxide treatment stage. As a result, peroxide stability is limited and bleaching effectiveness is reduced. The conditions of recycled paper processing, deinking and bleaching are especially conducive to enzyme peroxide degradation.
[0004] Some of the methods employed to stabilize hydrogen peroxide include biocide treatments (e.g. peracetic acid treatment), use of high hydrogen peroxide dosages and steep bleaching.
[0005] U.S. Pat. No. 5,728,263 describes the use of dialdehydes and acetals thereof, such as glutaraldehyde, to inhibit the decomposition of peroxide in the treatment of recycled and other fiber pulps. Hydrogen peroxide stability is enhanced by the addition of glutaraldehyde. Glutaraldehyde, however, has a poor safety profile and high concentrations of it are required to inhibit peroxide decomposition.
[0006] U.S. Pat. No. 5,885,412 describes the use of certain hydroxyl amines and alkyl derivatives, including hydroxylammonium sulfate, ascorbic acid and formic acid, that suppress or inhibit hydrogen peroxide degradation by enzymes, such as peroxidases and catalases, during bleaching of cellulose fibers and do not affect microorganisms.
[0007] Great Britian Patent Publication No. 2,269,191 describes the use of an organic peracid that has a disinfectant effect on catalase producing microorganisms at neutral or acidic pH.
[0008] U.S. Pat. No. 4,908,456 teaches the use of methylolated hydantoin, especially 1,3-dimethylol-5,5-dimethylhydantoin (DMDMH) as an antimicrobial agent.
[0009] U.S. Pat. No. 5,405,862 teaches the preparation of low free formaldehyde DMDMH compositions which are used in biocidal effective amounts in any medium in which microbial growth is to be retarded.
[0010] There is a need for a method of stabilizing hydrogen peroxide in the presence of catalase and other peroxide degenerating enzymes that is not hazardous.
SUMMARY OF THE INVENTION
[0011] The present invention is a method of stabilizing hydrogen peroxide in an aqueous solution, such as a circulating water slurry, comprising a peroxide, such as hydrogen peroxide. The aqueous solution may include organic matter. The method comprises adding an aldehyde donor, such as a methylolhydantoin, to the solution (or slurry). The inventors have discovered that aldehyde donors significantly reduce the decomposition of hydrogen peroxide by catalase and other peroxide decomposing enzymes, which are often present in recycled paper. As a result, less hydrogen peroxide needs to be added to a solution to effectively bleach organic matter in the solution. Furthermore, aldehyde donors are safe to handle and cost effective.
[0012] Another embodiment is a method of bleaching recycled papers in a circulating water slurry comprising organic matter. The method comprises adding hydrogen peroxide and an aldehyde donor to the slurry.
[0013] Yet another embodiment is a method of inhibiting catalase and/or other peroxide decomposing enzymes in an aqueous solution, such as a circulating water slurry, comprising adding an aldehyde donor to the aqueous solution.
[0014] Yet another embodiment is a method of stabilizing a peroxide in an aqueous solution comprising maintaining a peroxide stabilizing effective amount of at least one aldehyde donor in the aqueous solution.
[0015] Yet another embodiment is a method of inhibiting catalase and/or other peroxide decomposing enzymes in an aqueous solution, such as a circulating water slurry, comprising maintaining a peroxide decomposing enzyme inhibiting effective amount of at least one aldehyde donor in the aqueous solution.
DETAILED DESCRIPTION OF THE INVENTION
[0016] In any identified embodiments, the term “about” means within 50%, preferably within 25%, and more preferably within 10% of a given value or range. Alternatively, the term “about” means within an acceptable standard error of the mean, when considered by one of ordinary skill in the art.
[0017] The present invention provides a method of stabilizing a peroxide, such as hydrogen peroxide, in an aqueous solution comprising the peroxide. The method comprises adding to or maintaining an aldehyde donor in the aqueous solution. Generally, the peroxide is added to the solution in the form of a bleaching solution.
[0018] The aqueous solution can be (i) a circulating water slurry comprising organic matter or (ii) a slurry dilution water. Generally, a slurry dilution water contains little (<0.2% by weight), if any, organic matter. Slurry dilution waters are frequently added to dilute or form solutions containing organic matter, especially pulp. Furthermore, slurry dilution water is frequently recovered from circulating water slurries containing organic matter by methods known in the art.
[0019] The term “aldehyde donor” as used herein is defined as any material which is not an aldehyde but upon aqueous dilution liberates a compound which gives positive reactions with aldehyde identifying reagents, i.e. a compound which can identify aldehyde groups. Generally, the liberated compound has the formula
[0020] where R is any functional group. In other words, the term “aldehyde donor” includes any compound which is not an aldehyde but when hydrolyzed forms an aldehyde or a compound which gives positive reactions with aldehyde identifying reagents. Examples of aldehyde identifying reagents include, but are not limited to, Benedicts solution, Tollens reagent, and acetyl acetone.
[0021] Suitable aldehyde donors include, but are not limited to, imidazolidinyl urea, Quatemium-15, diazolidinyl urea, bromonitropropanediol, methenamine, 5-bromo-5-nitro-1,3-dioxane, sodium hydroxymethylglycinate, 3,5-dimethyl-1,3,5,2H-tetrahydrothiadiazine-2-thione, hexahydro-1,3,5-tris(2-hydroxyethyl)triazine, hexahydo-1,3,5-triethyl-s-triazine, polymethoxy bicyclic oxazolidine, tetrakis (hydroxymethyl) phosphonium sulfate, methylolhydantoins, and any combination of any of the foregoing.
[0022] Preferred aldehyde donors include, but are not limited to, methylolhydantoins, such as monomethyloldimethylhydantoins (MMDMHs), dimethyloldimethylhydantoins (DMDMHs), and any combination of any of the foregoing. Examples of methylolhydantoins include, but are not limited to, 1-hydroxymethyl-5,5-dimethylhydantoin (a MMDMH), 3-hydroxymethyl-5,5-dimethylhydantoin (a MMDMH), and 1,3-bis(hydroxymethyl)-5,5-dimethylhydantoin (DMDMH) mixtures (which are available as aqueous solutions under the tradenames Dantogard® and Glydant® from Lonza Inc. of Fair Lawn, N.J.). Other preferred aldehyde donors include, but are not limited to, low free formaldehyde compositions of dimethyloldimethylhydantoin, such as those described in U.S. Pat. No. 5,405,862, which is hereby incorporated by reference. Preferably, the aldehyde donor has a free formaldehyde concentration of less than 0.2% based on 100% total weight of aldehyde donor. Low free formaldehyde compositions reduce workplace exposure risk to formaldehyde. Generally, the weight ratio of methylolhydantoins to peroxide ranges from about 10:1 to about 1:1000.
[0023] According to a preferred embodiment, the aldehyde donor is a mixture of 1-hydroxymethyl-5,5-dimethylhydantoin, 3-hydroxymethyl-5,5-dimethylhydantoin, and 1,3-bis(hydroxymethyl)-5,5-dimethylhydantoin. Preferably, the mixture has a free formaldehyde concentration of less than 0.2% by weight, based on 100% total weight of the mixture. An example of a preferred mixture is a 65-70% aqueous solution of MMDMH, DMDMH, and 5,5-dimethylhydantoin (DMH) available under the tradename Dantogard® 2000 from Lonza, Inc of Fair Lawn, N.J.
[0024] The aldehyde donor significantly reduces the decomposition rate of hydrogen peroxide by catalase and other peroxide decomposing enzymes. The amount of the aldehyde donor added to the solution is typically sufficient to maintain a peroxide stabilizing effective concentration (i.e. a concentration sufficient to prevent decomposition of the peroxide) and/or a peroxide decomposing enzyme inhibiting effective concentration in the solution (such as a catalase inhibiting concentration). According to a preferred embodiment, the concentration of aldehyde donor maintained in the slurry is less than a microbicidally effective amount. Preferably, the concentration of aldehyde donor maintained in the solution ranges from about 1 to about 1,000 ppm, more preferably from about 30 to about 200 ppm, and most preferably from about 60 to about 120 ppm. According to one embodiment, the concentration of aldehyde donor maintained in the solution ranges from about 1 to about 5000 ppm, from about 100 to about 1000 ppm, from about 250 to about 500 ppm, from about 250 to about 750 ppm, from about 50 to about 500 ppm, from about 50 to about 750 ppm, from about 100 to about 200 ppm, or from about 200 to about 400 ppm.
[0025] Although many of the aldehyde donors identified above are also known biocides, their concentration in the solution can be less than that necessary to have a significant biocidal effect, i.e. they generally provide less than a 2 log reduction in the microorganism population in short contact time applications (e.g. 3 hours or less). The term “log reduction in the microorganism population” refers to the difference between the logarithm (base 10) of the microorganism count of an untreated substrate after a given contact time, such as 3 hours or less, and the logarithm of the microorganism count of an identical substrate treated with an aldehyde donor after the same contact time. According to one embodiment, the aldehyde donor causes a log reduction in microorganism population of less than 0.5 or 1.
[0026] A biocidal concentration of one or more biocides may also be added to or maintained in the solution. Suitable biocides include, but are not limited to, those described in Great Britain Patent Publication No. 2,269,191 ,which is hereby incorporated by reference. Other suitable biocides include, but are not limited to, thiocarbamates, such as sodium dimethyl dithiocarbamate; glutaraldehyde; dibromo nitrile propionamide (DBNPA); bromnitropropanediol; tetrakis (hydroxymethyl) phosphonium sulfate; bromonitrostyrene (BNS); benzisothiazolones; methylene bis(thiocyanate); 2-mercaptobenzothiazole (MBT); isothiazolines, including 5-chloro-2-methyl-4-isothiazolin-3 -one (CMI), 2-methyl-4-isothiazolin-3 -one (MI), octyl-4-isothiazolin-3-one, and mixtures thereof; bistrichloromethylsulfone (BTCMS); quaterary ammonium compounds, such as alkyldimethylbenzyl ammonium chlorides and dialkydimethyl ammonium chlorides; 2-bromo-4-hydroxyacetophenone (BHAP); and 5-oxo-3,4-dichloro-1,2-dithiol; and any combination of any of the foregoing.
[0027] Peracetic acid may be added to the solution to kill or inhibit the growth of microorganisms and/or to bleach any organic matter in the solution. Therefore, a microbicidally effective amount and/or a bleaching effective amount of peracetic acid may be added to or maintained in the solution.
[0028] The aldehyde donor may be added directly to the solution (e.g. slurry or slurry dilution water) or bleaching solution as a solid or liquid. Preferably, the aldehyde donor is added to the solution as a liquid. For example, the aldehyde donor may be added as an aqueous mixture. The concentration of aldehyde donor in such an aqueous mixture typically ranges from about 5 to about 95% by weight and preferably from about 20 to about 75% by weight, based upon 100% weight of total mixture. The aldehyde donor may be added before, simultaneously with, or after the hydrogen peroxide is added to the aqueous solution, or alternatively to the peroxide bleaching solution itself.
[0029] The hydrogen peroxide may be added alone or as a mixture with one or more biocides to the solution (or slurry) or peroxide bleaching solution. For example, a mixture of hydrogen peroxide and peracetic acid may be added to the solution (or slurry) or peroxide bleaching solution.
[0030] According to one embodiment, a blend of one or more aldehyde donors, CMI, and MI is added to the solution (or slurry). The blend may optionally contain isothiazoline stabilizers as known in the art. A preferred blend includes CMI, MI, and at least one of MMDMH and DMDMH. According to another embodiment, a blend of one or more aldehyde donors and a benzisothiazolinone is added to the solution (or slurry). A preferred blend includes benzisothiazolinone and at least one of MMDMH and DMDMH. Such aldehyde donor blends are described in U.S. Pat. Nos. 6,121,302 and 6,114,366, which are incorporated herein by reference.
[0031] The concentration of hydrogen peroxide added to or maintained in the solution is typically a bleaching effective concentration in the solution. The concentration of hydrogen peroxide maintained in the solution preferably ranges from about 1 to about 50,000 ppm, more preferably ranges from about 10 to about 10,000 ppm, and most preferably ranges from about 100 to about 1,000 ppm.
[0032] The solution may be, for example, a pulp slurry, a papermaking slurry, a mineral slurry or white water. White water is generally separated liquid that is re-circulated to a preceding stage of a papermaking process, especially to the first disintegration stage, where paper, water and chemicals are mixed.
[0033] Generally, a mineral slurry comprises of from about 50 to about 80% by weight of mineral matter, such as, but not limited to, calcium carbonate or clay. The mineral slurry may also contain an organic dispersing agent. Preferred organic dispersing agents include, but are not limited to, polyacrylates.
[0034] Typical pulp slurries in paper applications contaih from about 0.2 to about 18% by weight of organic matter, based upon 100% total weight of slurry. The organic matter is typically comprised of wood fiber (or pulp) and adjuvants, such as sizing and starch. Generally, the organic matter comprises from about 90 to about 99% by weight of wood fiber (or pulp), based upon 100% total weight of organic matter. According to a preferred embodiment, the wood fiber is at least partially derived from recycled paper.
[0035] The pulp slurry may also contain other adjuvants known in the art. Examples of such adjuvants include, but are not limited to, slimicides; sodium hydroxide (or other caustic); peroxide stabilizers, such as sodium silicate, magnesium sulfate, and polyphosphates; chelating agents, such as EDTA; fatty acids; and combinations thereof.
[0036] Generally, the pH of the solution ranges from about 7 to about 13 and preferably from about 8 to about 11. In another embodiment, the pH of the solution ranges from about 4 to about 13, preferably from about 7 to about 12, and more preferably from about 8 to about 11.
[0037] The following examples are intended to describe the present invention without limitation.
EXAMPLE 1
[0038] Process waters from a papermaking facility which uses recycled fibers were collected during a bleaching stage and allowed to stand for 2 hours to achieve total depletion of the hydrogen peroxide in the process waters.
[0039] Into five separate Pyrex beakers were placed 400 ml of the process water. One was retained as a control. 150 and 300 ppm of an aqueous solution containing 40% by weight of 1,3-bis(hydroxymethyl)-5,5-dimethylhydantoin (DMDMH) (Dantogard®) were added to two beakers for a total concentration of 60 ppm and 120 ppm of DMDMH, respectively. On an equivalent aldehyde basis, this corresponds to 0.65 mEq/l and 1.30 mEq/l, respectively. 150 and 300 ppm of an aqueous solution containing 55% by weight of glutaraldehyde were added to the remaining two beakers for a total concentration of 83 ppm and 166 ppm of glutaraldehyde, respectively. On an equivalent aldehyde basis, this corresponds to 1.66 mEq/l and 3.32 mEq/l, respectively. The samples were placed in a controlled water bath at 45° C. and stirred with a magnetic stirrer set on slow agitation.
[0040] To all the test samples, a sufficient volume of a 1% (by weight) hydrogen peroxide (H 2 O 2 ) aqueous solution was added to achieve a concentration of 20-25 ppm of hydrogen peroxide in the samples. At regular time intervals, over a 45 minute period, aliquots were removed and analyzed for peroxide residual (i.e. the concentration of hydrogen peroxide) using a thiosulfate titration kit (HACH Test Kit, Model HYP-1, available from Hach Company of Loveland, Colo.). The results, shown in Table 1, correlate to the amount of peroxide present at the specific time interval, expressed as ppm of hydrogen peroxide.
TABLE 1 H 2 O 2 Stabilization by DMDMH and Glutaraldehyde (expressed as ppm H 2 O 2 ) Time DMDMH DMDMH Glutaraldehyde Glutaraldehyde (min) Control (60 ppm) (120 ppm) (83 ppm) (166 ppm) 0 25 25 26 25 26 10 22 24 24 24 24 15 21 23 23 22 21 20 19 22 20 20 19 30 15 18 18 16 17 40 13 16 17 14 15 45 10 15 16 12 13
[0041] The results show that DMDMH provides superior peroxide stabilization compared to glutaraldehyde. On a ppm product basis, the DMDMH surpassed the performance of the glutaraldehyde. See Table 1. DMDMH surpasses the performance of glutaraldehyde when added at 38% lower concentrations. When considered on a molar aldehyde basis, it is demonstrated that DMDMH surpasses the performance of glutaraldehyde when added at a concentration 73% lower in aldehyde equivalents.
EXAMPLE 2
[0042] DMDMH hydrogen peroxide stabilization was demonstrated in a sample of white water obtained from a paperboard mill using recycled paper (50% mix, 15% corrugated, 15% news, and 20% other) as follows. The white water sample was diluted with 10 parts of sterilized tap water for every part of white water. Into three separate Pyrex° beakers, 100 ml of the diluted white water was added. One beaker was retained as a control. 250 and 500 ppm of an aqueous solution containing 40% by weight of DMDMH, available as Dantogard® from Lonza Inc., (i.e. 100 ppm of DMDMH and 200 ppm of DMDMH) were added to the remaining two beakers, respectively. The solutions were tested at 37° C. and a pH of 7.8. Hydrogen peroxide was added to the white water in quantities sufficient to achieve a concentration of 300 ppm H 2 O 2 . Aliquots were taken at the indicated times and analyzed for residual peroxide with a thiosulfate titration kit (Hach Test Kit, Model HYP-1). The results are shown in Table 2 as ppm H 2 O 2.
TABLE 2 Peroxide Residual (ppm H 2 O 2 ) Dantogard® Dantogard® Time (minutes) Control 250 ppm 500 ppm 0 300 300 300 10 136 160 180 20 70 94 127 30 42 68 97
[0043] Dantogard® provided significant hydrogen peroxide stabilization as shown in Table 2. After 30 minutes elapsed time, hydrogen peroxide residuals in the sample treated with 500 ppm Dantogard® were more than twice that in the untreated control.
EXAMPLE 3
[0044] The biocidal efficacy of Dantogard® at 250 and 500 ppm (i.e. 100 and 200 ppm of DMDMH) was determined as follows. 50 ml of the undiluted white water sample of Example 2 was treated with 250 and 500 ppm Dantogard®. The test water temperature was 37° C. and the pH was ˜7.0.
[0045] Microorganism counts were performed after 3 hours contact time using the tryptone glucose extract agar pour plate methodology described in the American Society for Testing and Materials (ASTM) E 1839-96, “Standard Test Method for Efficacy of Slimicides for the Paper Industry—Bacterial and Fungal Slime”.
[0046] The microorganism count values were then converted to their corresponding log value. The log microbial population reduction values were calculated by subtracting the log of the microorganism count for the respective Dantogard® sample from the log of the microorganism count for the control. The results are shown in Table 3.
[0047] Microorganism count reductions of only 0.06 and 0.23 log were observed for Dantogard® concentrations of 250 and 500 ppm, respectively.
TABLE 3 Log microbial Biocidal efficacious White Water Microorganism population according to ASTM Sample Count (cfu/ml) reduction E-1839-96 criteria* Untreated Control 1.3 × 10 8 — — 250 ppm 1.2 × 10 8 0.06 No Dantogard® 500 ppm 7.9 × 10 7 0.23 No Dantogard®
EXAMPLE 4
[0048] Hydrogen peroxide stabilization was demonstrated in another white water sample as follows.
[0049] Into three seperate beakers were placed 100 ml of a white water sample obtained from a tissue and towel mill using recycled newsprint as a pulp feed stock. The recycled feed stock had been subject to deinking and peroxide bleaching in the tissue and towel mill. One beaker was retained as a control. 250 and 500 ppm of Dantogard® were added to the other two beakers, respectively.
[0050] The test temperature was 32° C. and the pH was 7.6. 30 ppm of hydrogen peroxide was added to the samples. Aliquots were taken at the indicated times and analyzed for residual peroxide using a thiosulfate titration kit (Hach Test Kit, Model HYP-1). The results are shown in Table 4 below.
TABLE 4 Peroxide Residual (ppm H 2 O 2 ) Time (minutes) Control 250 ppm Dantogard® 500 ppm Dantogard® 0 30 30 30 20 14 21 22 40 8 15 16
[0051] Dantogard® provided significant hydrogen peroxide stabilization as shown in Table 4. After 40 minutes elapsed time, the concentration of hydrogen peroxide in the sample with 500 ppm Dantogard® was twice that of the untreated control.
EXAMPLE 5
[0052] The Dantogard® concentrations found to provide hydrogen peroxide stabilization in Example 4 (250-500 ppm) were again found to be below the concentrations required to provide significant biocidal efficacy according to ASTM E 1839-96.
[0053] 50 ml of an undiluted white water sample of Example 4 was treated with Dantogard® at concentrations of 250 and 500 ppm (100 and 200 ppm DMDMH). The test water temperature was 32° C., and the pH was 7.6.
[0054] Microorganism counts were performed after 3 hours contact time using the tryptone glucose extract agar pour plate methodology as described in ASTM E 1839-96.
[0055] The microorganism count values were then converted to their corresponding log value. The log microbial population reduction values were calculated by subtracting the log of the microorganism count for the Dantogard® sample from the log of the microorganism count for the control. The results are shown in Table 5.
TABLE 5 Biocidal efficacious Microorganism Log Microbial by Count Population ASTM E 1839-96 Agent (cfu/ml) Reduction criteria* Control time zero 8.0 × 10 6 — — Control 1.1 × 10 7 0 — Dantogard® 5.1 × 10 6 0.37 No 250 ppm Dantogard® 1.9 × 10 6 0.80 No 500 ppm
EXAMPLE 6
[0056] Direct inhibition of catalase by DMDMH solutions was demonstrated by monitoring catalase promoted hydrogen peroxide decomposition in sterile media.
[0057] Hydrogen peroxide solutions containing 470 ppm active peroxide in sterile Butterfield's phosphate buffer (pH=7.0) were treated with 1.2 units of catalase ( A. niger available from Sigma Aldrich of St. Louis, Mo. (C-3515)) alone or with 263 or 526 ppm of Dantogard® 2000, available from Lonza Inc. of Fair Lawn, N.J., or 526 ppm of an aqueous 49% glutaraldehyde solution. Dantogard® 2000 is a 65% aqueous mixture of DMDMH, MMDMH and DMH having a minimal free formaldehyde concentration. The peroxide decomposition rate was monitored during the decrease in peroxide concentration from 390 to 350 ppm by ultraviolet absorbance at 240 nm. The temperature was 23° C. The results are shown Table 6.
TABLE 6 Normalized Peroxide Decomposition Decomposition Sample Rate (ppm/sec) Rate Control 0.230 1.00 263 ppm 0.143 0.62 Dantogard® 2000 526 ppm 0.073 0.32 Dantogard® 2000 526 ppm 0.230 1.0 glutaraldehyde (49%)
[0058] Dantogard® 2000 provided significant catalase inhibition. 263 ppm of Dantogard® 2000 decreased the hydrogen peroxide decomposition rate to 62% of that of the untreated control. 526 ppm of Dantogard® 2000 decreased the hydrogen peroxide decomposition rate to 32% of that of the untreated control.
EXAMPLE 7
[0059] Direct inhibition of catalase by DMDMH solutions was demonstrated by monitoring catalase promoted hydrogen peroxide decomposition in a pH 9.2 borate buffer.
[0060] Hydrogen peroxide solutions containing 450 ppm active peroxide in a 0.57% borax buffer (pH=9.2) were treated with 1.2 units catalase ( A. niger derived Sigma Aldrich C-3515) in the presence and absence of Dantogard® (Lonza Inc. of Fairlawn, N.J.). The peroxide decomposition rate was monitored during the decrease in peroxide concentration from 390 to 350 ppm by ultraviolet absorbance at 240 nm. The temperature was 23° C. The results are shown Table 7.
TABLE 7 Peroxide Decomposition Rates Rate Normalized Product (ppm/sec) Decomposition Rate Control 0.106 1.00 Dantogard 500 ppm 0.051 0.48
[0061] Dantogard® provided significant catalase inhibition. A concentration of 500 ppm decreased the hydrogen peroxide decomposition rate to 48% of that of the untreated control.
[0062] All patents, publications, applications, and test methods mentioned above are hereby incorporated by reference. Many variations of the present matter will suggest themselves to those skilled in the art in light of the above detailed description. All such obvious variations are within the patented scope of the appended claims. | The present invention is a method of stabilizing hydrogen peroxide in an aqueous solution, such as a circulating water slurry, comprising a peroxide, such as hydrogen peroxide. The aqueous solution may include organic matter. The method comprises adding an aldehyde donor, such as a methylolhydantoin, to the solution (or slurry). The inventors have discovered that aldehyde donors significantly reduce the decomposition of hydrogen peroxide by catalase and other peroxide decomposing enzymes, which are often present in recycled paper. As a result, less hydrogen peroxide needs to be added to a solution to effectively bleach organic matter in the solution. Furthermore, aldehyde donors are safe to handle and cost effective. Another embodiment is a method of bleaching recycled papers in a circulating water slurry comprising organic matter. The method comprises adding hydrogen peroxide and an aldehyde donor to the slurry. Yet another embodiment is a method of inhibiting catalase and/or other peroxide decomposing enzymes in an aqueous solution, such as a circulating water slurry, comprising adding an aldehyde donor to the aqueous solution. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of priority under USC §119(e) of provisional application No. 61/641,361, filed May 2, 2012, entitled “Ridge Lap Dental Implant”, hereby incorporated by reference herein,
BACKGROUND OF THE INVENTION
[0002] The present invention relates generally to dental implants, and more specifically to a dental implant having an improved coronal configuration to take advantage of the presenting bony topography that is often present immediately following tooth extraction prior to any healing or remodeling process. This ridge lap dental implant is suitable, but not limited to, both immediate and delayed implant placement in the upper anterior region of the mouth.
[0003] Dental implants are used in place of missing natural teeth to provide a base of support for single, multiple teeth or full arch prosthetics. These implants generally include two components, the implant itself and the prosthetic mounting component referred to as an abutment upon which the final prosthesis is installed. The implant has apical and coronal ends, whereby the coronal end accepts the base of the prosthetic abutment using connection mechanisms of different designs. One such mechanism is a deep female conical receptor with an internal alignment or anti-rotational element such as a hex, double hex, spline or other single/multi sided arrangement used for prosthetic alignment and anti-rotational stability. Deep female conical connections have been shown to be the most stable mechanisms by preventing micro movement between the implant body and the abutment under normal loading conditions. It has been suggested that preventing micro movement is one of the key factors required for crestal bone maintenance.
[0004] Dental implants are used in place of extracted (and/or missing) natural teeth as the base of support for an abutment and final prosthesis to restore normal oral function. But once a tooth is no longer present, the bone from which the tooth originated heals and is forever changed. Accordingly, while dental implants should be designed to take into account the healing process of bone after tooth loss, this is seldom the case. In fact, dental implant designs for the most part are not designed to take into consideration the presenting bony topography prior to implant placement. In fact, it is common for surgeons to modify or flatten the bone to suit the implant configuration rather than design the implant to suit the presenting anatomy.
[0005] In practice, the implant body is surgically inserted in the patients jaw and becomes integrated with the bone. This can be done immediately at the time of tooth extraction or in a delayed manner allowing healing and remodeling to occur first. More specifically, the implant body is screwed or pressed into holes drilled in the respective bone or the apical end of extraction socket is prepared to accept the insertion of a dental implant immediately. The surface of the implant body is characterized by macroscopic and microscopic features that aid in the process of osseointegration. Once the implant is fully integrated with the jaw bone or in some cases at the time of insertion the abutment is ready to be mounted. For two-stage implant designs, the abutment passes through the soft tissue that covers the coronal end of the implant after healing and acts as the mounting feature for the prosthetic device to be used to restore oral function. Implants of the single-stage design extend at least partially through the soft tissue at the time of surgical insertion. The coronal end of the single stage implant body acts as a built-in abutment with the margin of the coronal collar usually being employed as the margin of attachment for the prosthesis used to restore oral function. These components, the implant and abutment, are typically fabricated from titanium or titanium alloy as well as zirconia based, alumina based or sapphire based ceramics. In some instances, ceramics and metals are combined to make a single component, though this is usually limited to the abutment component of the implant system. Titanium zirconium alloys and in the future nano structure titanium could become used due to significant increased strength.
[0006] Implant designs have gone through a considerable amount of trial and error in an attempt to deal with the issue of the bone not healing evenly once a tooth has been extracted. It has been found that bone heals based on the principles of bone biology, surrounding bony and soft tissue anatomy, as well as blood supply to the area. To a certain degree, bone healing and/or remodeling is also influenced by the placement and subsequent loading of an implant fixture. Only a limited number of studies have been conducted regarding bone loss patterns following tooth loss. Two such studies, one by Pietrokovski and Massler, published in the Journal of Prosthetic Dentistry in 1967; and another by Cawood and Howell, was published in the International Journal of Oral and Maxillofacial Surgery in 1991, are included as reference.
[0007] One can construe from these studies that for a time period as short as several months, the highest point of bone anatomy is toward the lingual side of extracted teeth after healing with considerably more remodeling/resorption on the buccal aspect. Due to the natural bony contours in the anterior area of the upper jaw, this healing pattern, often referred to as facial collapse of bone, is more immediate there than in the posterior upper and lower jawbones
[0008] In the 1980's one of the most commonly placed implant designs was the Branemark type dental implant. As with most traditionally designed implants, and a number today, the Branemark type fixture relied on a flat to flat matting surface perpendicular to the long axis of the implant body as the mating interface when joining the implant and the abutment together. This design usually displays a bone loss pattern described as a cupping of the bone at the coronal end of the implant usually down to the first major thread on the implant body. This bone loss pattern usually stabilizes after about one year of function with vertical bone loss of approximately 1.5 to 2.0 mm.
[0009] There are dental implants systems that typically do not demonstrate a cupping bone loss pattern. Two such implant systems are by Astra Tech and Ankylos. Both of these implants have an internal female conical connection and do not rely on flat to flat mating surfaces at the implant/abutment interface. However, the Ankylos surgical protocol suggests placing the implant two millimeters below the crest of bone because the philosophy is to allow bone to grow over the top of the implant and cover at least part of the platform at the coronal aspect of the fixture which extends outward from the abutment conical connection penetration. The Astra protocol is to place the implant at bone level or very slightly below and have the bone integrate apically from the most apical aspect of the reverse bevel at the coronal aspect of the Astra Tech Profile fixture.
[0010] Astra Tech now offers implants with a sloping coronal contour such that the height of lingual bone crest is engaged and preserved in sloped ridge situations. In particular, U.S. Pat. No. 7,270,542, to Cottrell, incorporated herein by reference, is directed to such a modified sloped top dental implant fixture, Dental implants made to these design specifications make it easier for surgeons to place implants ideally and maintain the bony topography after healing remodeling has occurred. This modified sloped top dental implant is commercially available as the Astra Tech Profile, and is generally illustrated by FIG. 1 herein.
[0011] The Astra Tech system mentioned above has essentially been modified to develop a dental implant with a sloping coronal contour that is convex when viewed in FIG. 1 . Much of the success of this implant is credited with Astra Tech design having a combination of a rigid conical abutment connection and the presence of coronal stress reducing micro threads on the implant body which in combination greatly reduce, and in most cases, eliminate the aforementioned bone loss patterns. The reverse bevel at the top of the implant inherent in the design of fixtures with a deep conical connection may also be important as well. It has been proposed, and possibly validated by Degidi in the International Journal of Periodontics and Restorative Dentistry 2012 June: 32(3):323-8, and by Degidi in the Clinical Oral Implant Res. 19, 2008, 276-282 that the circular connective tissue fibers at the base of the implant gingival complex, that develop above the implant once the final abutment is installed, may help prevent apical soft tissue migration acting as a mechanical support mechanism. Both Degidi references are hereby incorporated by reference herein. The Ankylos design has bone growing over the platform at the top of the implant but must be placed deeper below the level of the most apical crestal bone available in order for bone to grow over the top of the fixture. The Ankylos implant has more of a coronal shoulder than Astra's reverse bevel in order to maintain adequate wall thickness for the Ankylos approximate six (6) degree internal conical connection but the shoulder essentially has the same effect with regard to the circular connective tissue fibers. The present disadvantage is that in many instances one side of the implant platform which is, as mentioned above, relatively flat has to be buried deeper than necessary for this overgrowth of bone to occur. This is particularly true in the upper anterior region of the mouth where the Ankylos fixture must be significantly buried on the lingual aspect due to the presenting anatomy in that region, see FIG. 7 herein.
[0012] However, while the sloped top implant works very well with extraction sites that have been allowed to heal, and the implant placed following the delayed protocol, it may not be the ideal design when implanted immediately following tooth extraction. Certainly sloped top fixtures work better than traditional flat topped fixtures in the upper anterior region of the mouth, but the contours are still not exactly ideal for immediate placement. In order to compensate for the mismatch between the extraction socket topography and the sloped top design, Cottrell has applied for a patent (application Ser. No. 12/494,510) on a design that has a modified coronal contour. This design calls for the mesial length to be greatest and the buccal length shortest with the lingual and distal dimensions intermediate in length. Viewed from the mesial aspect the coronal contour is convex, as is the contour of the Profile fixture in FIG. 1 as referenced above. The contours of the asymmetric fixture do not perfectly mimic the CEJ contours of the upper anterior teeth because implants are undersized relative to the extraction socket following the immediate placement protocol and as a result some remodeling is going to occur. While the design takes into consideration the height of the lingual side of extraction socket in the upper anterior region it does not follow the contours of the interproximal bone levels which are even higher. The Asymmetric Design, as it is called, tries to anticipate the bone remodeling upon healing remodeling and still preserve some of the interproximal bone height. Unfortunately, while the Asymmetric implant design is ideal in approach it does present a problem. Being asymmetric in character, different fixtures are required for the upper right and upper left anterior regions in the mouth and different fixtures for the upper/lower right and upper/lower left quadrants of the mouth. Consequently, there is concern that potential surgical and inventory complications could arise for the surgeon.
[0013] At the coronal aspect of a dental implant placed immediately in the upper anterior region of the mouth a gap is generally present on the mesial, distal and buccal sides on the fixture as only the apical end is firmly anchored in bone and the lingual side ideally but not always in contact with the bone. Accordingly, as mentioned before some remodeling is going to take place as these gaps fill in with new bone. The objective of the asymmetric concept was to design the coronal contour of the dental implant that anticipates how this will occur when immediate implant placement protocol is undertaken. A compromise must be established between the bony contours that exist around the coronal contour of the extraction socket and the contours of the asymmetrical dental implant which best takes into account the angulation that the implant must follow in the extraction socket while anticipating the remodeling process compared to the delayed implant placement protocol.
[0014] However this particular improvement caused issues because different fixtures would be required in the upper anterior for the upper right and left sides of the mouth and for the upper left/lower right and upper right/lower left quadrants of the mouth. Additionally, Astra Tech was recently purchased by Dentsply International, who already owns the Ankylos system. As mentioned above, the recommended Ankylos protocol is to bury the implant. So the general object of the present invention is to offer a grand compromise. If Ankylos suggests burying the top of the implant 2.0 millimeters below the lowest level of the available bone, the present disclosure is suggesting there is a way to contour the top of the fixture to prevent burying aspects of the Ankylos shoulder deeper than Ankylos presently recommends, especially on the lingual aspect in the upper anterior region of the mouth. Further the present disclosure would satisfy Astra Tech and others main objection since only one implant design for upper right and left sides of the mouth and all posterior quadrants would be required. Also, since Ankylos buries the top of the fixture having the implant slightly longer on the mesial than the distal isn't as important. While it is more of an issue for a bone level design like Astra Tech's in reality many surgeons bury those fixtures to a degree as well, so being perfectly coronally contoured as the asymmetric design suggest maybe isn't as important for bone level designs as Astra Tech's either. Accordingly, what is being disclosed is a smooth, continuously contoured coronal profile without abrupt change in direction such that the longest mesial and distal lengths are equal, the buccal lengths are shorter than their most adjacent mesial and distal lengths and the lingual lengths are shorter than their most adjacent mesial and distal lengths such that the shortest lingual length is longer than the shortest buccal length. Further, when viewed from the mesial or distal, the outer bone engaging aspect of the coronal contour of the outer aspect of the implant fixture is convex. It is also proposed that in the most ideal configuration that all corresponding mesial and distal lengths, corresponding lingual lengths as well as corresponding buccal lengths are equal. In this case, the meaning of corresponding would be the same lengths in a mirror image reflection such that if the implant were sectioned in the middle buccal to lingual both sides would be identical but a mirror image of one another. The body of the implant can be a tapered or straight walled fixture. Going forward this contour will be referred to as the Ridge Lap design as the coronal contour mimics the underside of a ridge lap pontic in a bridge prosthesis. Anyone skilled in the art will appreciate that as long as the mesial and distal greatest lengths are equal that they do not necessarily have to be correspondingly equal as herein defined. The same would be true for the buccal and lingual lengths as corresponding lengths could be slightly unequal. However, this would result in asymmetry and void one objective of the Ridge Lap concept but done in a way that is not detectable clinically. In other words, the mesial half and the distal half of the coronal contours being mirror images of one another. The proposed Ridge Lap coronal contour, while not as ideal as the Asymmetric Design, will still help overcome the challenge of preserving at least some of the interproximal bone height and allow Ankylos surgeons to reduce the depth of fixture placement, particularly on the lingual aspect as shown in FIG. 8 , but still allowing bone overgrowth onto the shoulder of the fixture. The Ridge Lap design allows the top of either the Astra Tech or Ankylos type implant design to better follow the surrounding bony contours in the upper anterior region of the mouth in particular at the time of extraction and still be easy for the surgeons to place clinically.
[0015] Interestingly, the Ridge Lap contour also has application for single stage implants as well. Straumann is now the largest implant company in the world and at least 50% of their sales are single stage implants only introducing a bone level fixture into the marketplace in the past 3-4 years. Single stage implants with a level coronal platform do work reasonably well in the upper posterior region of the mouth but require extremely accurate placement by the surgeon. Since the bone and soft tissue in the upper posterior is often flat, the top of the single stage implant works well to provide a margin for the final prosthesis. However, in the lower posterior, the anatomy more often than not shows buccal bone remodeling and the level of the bone and soft tissue on the buccal aspect is more apical. The Ridge Lap contour gets its name by following the underside of a ridge lap pontic of a fixed bridge prosthesis. Contouring the top of a single stage implant to follow the same contour would overcome some of the issues that single stage implants present in the lower posterior. Namely they are often buried deeper than desirable so the top of the implant is not exposed on the buccal aspect. This buries the lingual side of the implant and it can be at times difficult to remove the final luting cement. In years past, cement contamination down the side of the implant was overlooked but recently that has become a hot topic of discussion. Numerous clinicians have presented cases showing bone loss in implant cases where cement has been found to be a contaminant. This has been one of the reasons custom abutments of bone level implants have become so popular since the margin for the final prosthesis is machined to follow only slightly below the soft tissue contours. Therefore, the Ridge Lap contour as applied to a single stage implant as shown in FIG. 10 is considered to be very desirable.
[0016] Accordingly, it is the general object of the present Disclosure to provide an implant with a coronal contour that will do much of what Cottrell's Asymmetric Design would accomplish while simplifying the design to have equal mesial and distal contours.
[0017] It is a further object of the present disclosure to overcome the challenge of maintaining at least some of the interproximal bone height that has to date been difficult to maintain.
[0018] It is another object of the present disclosure to provide a modified dental implant design combining the elements that are known to work in overcoming crestal bone loss such that the problems related to immediate implant placement with respect to maintaining the natural bony topography present at the time of tooth extraction can at least be partially accomplished.
[0019] It is a more specific object of the present disclosure to enable single state implants to be placed in a delayed manner in healed sites that exhibit buccal bony remodeling requiring that the buccal aspect of the implant to be placed more apically to follow the soft tissue topography without burying the lingual aspect of the implant.
[0020] These and other objects, features and advantages of the present invention will be clearly understood through a consideration of the following detailed description.
SUMMARY OF THE INVENTION
[0021] A dental implant having a longitudinal body with an outer bone engaging surface, apical and coronal ends, and mesial, distal, buccal and lingual sides. The body having lengths along its outer surface that include mesial, distal, buccal and lingual lengths when positioned within a jawbone. The coronal end has an inner female conical shape with a coronal bevel having proximal and distal aspects. The bevel has a bone engaging contour to provide a continuous asymmetric coronal contour without any abrupt changes in direction such that the longest mesial and distal lengths are equal, the buccal lengths are shorter than their most adjacent mesial and distal lengths, and the lingual lengths are shorter than their most adjacent mesial and sistal lengths such that the shortest lingual length is longer than the shortest buccal length. And, when viewed from the mesial or distal aspects, the bone engaging coronal contour is convex without abrupt interruption in direction from a most lingual to a most buccal point.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a side perspective view of a prior art sloped top dental implant.
[0023] FIG. 2 is a side perspective view of the Ridge Lap implant of the present disclosure.
[0024] FIG. 3 is a side view of a comparison of the implant contours of FIGS. 1 and 2 .
[0025] FIG. 4 is a side elevated view of the Ridge Lap implant of the present disclosure.
[0026] FIG. 5 is a frontal view of FIG. 4 .
[0027] FIG. 6 is a frontal view of the Ridge Lap implant of the present disclosure reflecting the Astra Tech design and placement philosophy.
[0028] FIG. 7 is a side perspective view of a prior art Ankylos implant reflecting the Ankylos design and placement philosophy.
[0029] FIG. 8 is a cross sectional view of an Ankylos implant reflecting the Ridge Lap design modification and reflecting the Ankylos placement philosophy.
[0030] FIG. 9 is a cross sectional view of a prior art single implant with a flat top reflecting the Straumann coronal configuration.
[0031] FIG. 10 is a cross section view of a Straumann type single stage implant with a coronal Ridge Lap contour shown more ideally following the soft tissue contour present in the lower posterior region of the mouth.
[0032] FIG. 11 is a top view of an Ankylos type design describing the various sides when positioned in the mouth.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] Referring now to the Figures, and in particular FIG. 1 , the aforementioned prior art sloped top implant 10 is illustrated implanted within the jawbone 12 . The body of the implant 10 is preferably, but need not be, comprised of screw threads to aid in the implantation process. The lower portion 14 of the implant body includes larger threads 16 a than the smaller threads 16 b of the upper portion 18 . It has been found that the smaller threads significantly reduce stress forces transmitted to bone and helps to preserve cortical bone. They also increase the fixture strength by maintaining wall thickness without changing the outer dimension of the implant, compared to using larger and deeper threads in the same area of the implant. The deep threads of current practices tend to dig into the body of the implant and weaken it. In any event, other means may be used on the outside surface of the implant 10 , and specifically upper portion 18 , such as small grooves or laser etched ridges affixed to the implant within the bone 12 , with the apical end 20 securely anchored. The surface of the implant 10 may be textured/coated in differing ways to promote osseointegration. FIG. 1 further illustrates the soft tissue 11 over laying the bone 12 , the buccal side 13 , the lingual side 15 , the conical interface 17 , and the convex bone engaging contour 27 of the implant 10 .
[0034] The basic concept of the prior art implant 10 of FIG. 1 is the contouring or sloping of the coronal 22 or top of the implant fixture such that the lingual bone 24 can be engaged at a more coronal level and preserved. This coronal contour can be a straight line or a convex contoured design so long as the lingual bone engaging side 26 of the implant body (which would become the lingually oriented side of the implant fixture) is longer in the apical-coronal bone engaging dimension than any other apical-coronal bone engaging dimension. The reverse bevel 28 at the coronal aspect 22 of the implant body is necessary to provide additional wall thickness for the internal female conical connection 17 . The angle of this reverse bevel can continuously vary so that the bone engaging surface 27 does not necessarily follow the exact contours of the most coronal contour 22 of the implant.
[0035] As previously discussed, while the sloped top design of the prior art of FIG. 1 works very well with extraction sites that have healed, and the delayed placement protocol followed, it may not be the ideal design when implanted immediately following an extraction. For such immediate implantation, the present invention provides for a more exaggerated convexity of the top design. In particular, and referring to FIG. 2 , the more coronally contoured end 40 of the implant 30 and especially the convexly contoured bone engaging coronal interface 41 is illustrated within jawbone 12 . The body of the implant 30 is preferably, but need not be, comprised of screw threads to aid in the implantation process. The lower portion 32 of the implant body includes larger threads 34 a than the smaller threads 34 b of the upper portion 36 . Other means may be used on the outside surface of the implant 30 affixed to the implant within the bone 12 , so long as the apical end 38 thereof is securely anchored. The surface of the implant 30 may be textured/coated in differing ways to promote osseointegration.
[0036] The basic concept of the implant of the present invention is the convex contouring of the coronal or top 40 of the implant fixture such that the bone engaging contour 41 at the most apical level of the reverse bevel 44 anticipates the crestal remodeling as gaps between the extraction socket walls and in the implant fixture fill in with new bone and then preserve that topography. The coronal end is contoured such that the corresponding greatest lengths of the implant body are equal on the mesial and distal aspects when inserted into the jawbone, the buccal lengths are shorter than their most adjacent mesial and distal lengths with the corresponding buccal lengths being equal and the corresponding lingual lengths longer than their corresponding buccal lengths but less than their adjacent mesial or distal lengths. The reverse bevel 44 at the coronal aspect 40 of the implant body also provides additional wall thickness for the internal female conical connection. This reverse bevel can be of a constant or variable angle relative to the fixture's long axis. FIG. 2 shows that the bevel 44 can continuously vary, for example, by having a steeper angle on the buccal side 44 a than the lingual side 44 b . In the case of the Ankylos type implant, the bevel can be of a very extreme angle forming almost or at 90 degrees with the fixture long axis resulting in a continuous 90 degree shoulder. However, a variably angled shoulder for the Ankylos design as shown in FIG. 8 is a more preferred coronal contour.
[0037] The Ridge Lap implant of FIG. 2 and the prior art sloped top or Profile implant of FIG. 1 are compared in FIG. 3 . The contour of bone 50 is what is found around and between the natural tooth. Comparing this natural contour 50 with the delayed protocol healing bone topography 52 it is hoped that an intermediate contour 54 can be maintained that follows the proposed bone engaging contour 41 at the coronal aspect of the Ridge Lap implant. Contour 52 is the contour of a healed ridge following tooth extraction and is more specifically the contour in the middle of a single extraction site between two upper anterior teeth. However, a dental implant, while generally not as wide as the extracted tooth to be replaced does extend mesial and distal from the middle of the extraction socket. Some of the bone between the midline of the extraction socket and the contour around the natural tooth being extracted may be maintained or even regenerated if lost due to pathology using growth factors. In other words, not all of the bone noted by 56 will necessarily be resorbed. And, even if it has been lost due to pathology it may be possible to be partially regenerated utilizing recent advancements in bone grafting techniques, especially those involving growth factors that enhance healing and reduce the amount of bony remodeling. Therefore, it is proposed that an immediate contour 54 , can be achieved or maintained on a reasonably consistent clinical basis by experienced clinicians. It is further proposed that this bone can be maintained if a dental implant with a proven track record of bone level maintenance such as the AstraTech design is used and the proposed corresponding Ridge Lap coronal configuration is incorporated therein.
[0038] More particular dimensions of an embodiment of the present disclosure are illustrated in FIGS. 4 and 5 . The side view of FIG. 4 shows the general length 60 of the implant 30 . The overall lengths on the bone engaging surface of the implant varies depending upon the general side of the implant. In particular, the length 60 of the implant is greatest and correspondingly equal on the mesial 58 or distal side 59 when inserted into the human jawbone, represented by the mesial view of FIG. 4 and is shortest on the generally buccal side 13 , or the view of FIG. 5 . The implant lengths on the lingual side 15 are shorter than their most adjacent mesial and distal lengths and longer than their corresponding lengths on the buccal aspect 13 .
[0039] It is the more apical or outer aspect 68 of the reverse bevel 44 on the coronal aspect of the fixture 30 that determines the length of the bone engaging surfaces upon insertion into the human jawbone for the different sides of the implant. While the coronal design is a bevel 44 which includes a top 66 , a bottom 68 and variable angle X 70 , it is the bone engaging surfaces that remains the crux of the disclosure. In that regard, although the width 72 of the top is important, it is height 64 of the top which affects the overall length 60 and therefore the bone engaging surfaces of the implant. It is important to note that while the greatest overall lengths of the implant are on the mesial and distal sides when implanted in the jawbone, the greatest length is not necessarily in the center of the mesial or distal aspect of the fixture. More particularly, FIG. 4 shows the centerline 76 of the implant with the longest point 78 to the tongue or lingual side 15 of center.
[0040] As previously discussed, these dimensions may need to be adapted to the particular position of the implant with the jawbone. Turning now to FIG. 6 , an implant utilizing the principles of the present invention is shown inserted within the maxilla just distal to the jaws centerline 80 . This placed implant shows the relative lengths of the different bone engaging sides of the implant body. For example, the lengths are now equal and greatest on the generally mesial side 58 and distal side 59 and shortest on the generally buccal side 13 ; while the lingual lengths on the lingual side 15 are shorter than their most adjacent mesial 136 and distal length 138 and longer than their corresponding buccal lengths.
[0041] FIG. 6 further illustrates other important features of a tooth prosthesis. For example, once the implant 30 is positioned, the abutment 90 is inserted into the conical interface 17 and the subsequent crown 92 can be placed,
[0042] FIG. 7 shows an Ankylos implant 94 placed in an immediate extraction socket 96 reflecting the Ankylos placement protocol of submerging the implant approximately 2 . 0 millimeters 97 below the most apical bone level 98 . Bone crests 98 and 99 show bone growing over the shoulder 101 of the implant. The dimension 100 is included for reference to be compared to the similar dimension 102 of the present disclosure in FIG. 8 . The conical interface 17 of the Ankylos type implant in this instance is approximately six degrees.
[0043] FIG. 8 shows an Ankylos implant with a Ridge Lap coronal configuration 105 placed in an immediate extraction socket 96 again reflecting the Ankylos placement protocol of submerging the implant approximately 2 . 0 millimeters 97 below the most apical crestal bone level 98 . Bone crests 98 and 99 show bone growing over the shoulder of the implant but in this configuration the bone on the lingual aspect is shown growing over the shoulder of the implant at a more coronal level. The dimension 102 in FIG. 8 is less than the distance 100 in FIG. 7 representing that a more coronal level of lingual bone being maintained. The dimension 103 in FIG. 8 shows the greater height of interproximal bone level being maintained using the Ridge Lap configuration 105 .
[0044] FIG. 9 shows a single stage implant 106 of the Straumann type implanted in the jawbone 12 as often found in the lower posterior region after tooth loss and bone remodeling. The coronal contour 108 is flat and perpendicular to the fixture long axis 110 . The top of the fixture is shown relatively level with the soft tissue 112 on the buccal aspect 13 and the corresponding lingual level is shown submerged 114 below the soft tissue level 115 on the generally lingual aspect.
[0045] FIG. 10 shows a single stage implant 116 of the Straumann type implanted in the jawbone 12 as often found in the lower posterior region after tooth loss and bone remodeling but reflecting the Ridge Lap coronal configuration 118 . The coronal contour is convex 120 compared to the long axis 110 in this side view shown and the top of the fixture is shown relatively level with the soft tissue 122 on the buccal aspect 13 and the corresponding lingual level shown again relatively level with the soft tissue 124 on the lingual aspect 15 . Clearly the top 118 of the single stage implant with the Ridge Lap configuration in FIG. 10 follows the coronal soft tissue contours 126 much more ideally than the flat top 108 of the single stage implant 106 of FIG. 9 .
[0046] FIG. 11 is an illustration of most adjacent lengths. Implants once imbedded in the jawbone have mesial, distal, buccal and lingual orientation sides. Since most implants have a flat coronal configuration the lengths on all sides are equal. However, when the top or coronal aspect of an implant is contoured the lengths become unequal. Looking down at the top of the implant 127 in FIG. 11 the four sides, namely the mesial 58 , distal 59 , buccal 13 and lingual 15 are represented by ninety 90 degree divisions 128 , 130 , 132 and 134 . The point 136 would represent the most adjacent mesial length for all lingual lengths and point 138 would be the location of the most adjacent distal length for all the lingual lengths. The point 140 would represent the most adjacent mesial length and the point 142 would be the location of the most adjacent distal length for all buccal lengths.
[0047] The top view of FIG. 11 is further illustrative of the relationship between the positions about the sides of the implant. In particular, the midline or centerline 144 cuts between the mesial 58 and distal 59 sides. Corresponding mirror image lingual lengths 146 and 148 are shown on the lingual side 15 . Similarly, corresponding mirror image buccal lengths 152 and 156 are shown on the buccal side 13 . Accordingly, the corresponding lingual and buccal lengths are those points ( 146 / 152 and 148 / 144 ) across the top view. Similarly, the corresponding mesial and distal lengths are those points ( 154 / 150 ) across the top view. | An asymmetrically placement designed to preserve bone by having the coronal aspect being compatible with the bony anatomy at the time of tooth extraction. The implant may be of either a single or two state design. By modifying the top of the implant fixture to partially mimic the bony anatomy at the time of the extraction more crestal bony anatomy can be preserved and bone growth encouraged. | 0 |
REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Applications Nos. 60/814,409, filed Jun. 15, 2006; 60/814,495, filed Jun. 15, 2006; 60/814,497, filed Jun. 15, 2006; 60/855,577, filed Oct. 30, 2006; 60/873,657, filed Dec. 8, 2006; and U.S. Patent Publication No. 2007/0290082, filed May 4, 2007; the complete disclosure of each of which are incorporated herein, in the entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a device for handling solid materials, such as hair, to reduce clogging of household sink, tub, and shower drains. More particularly, the present invention relates to a manually operable device for reducing the size of pieces of hair and other solid waste materials to smaller pieces less likely to accumulate and clog a drain.
[0004] 2. Description of Related Art
[0005] Drain receptacles for sinks, showers, and bath tubs frequently have strainers and filters covering or sitting in their openings so as to prevent solid materials from entering the drain conduit and clogging it at a downstream location. Such strainers are intended to allow liquid to pass while stopping the solid materials. However, in order for such devices to perform satisfactorily, they must be regularly cleaned, because they are prone to clogging. Cleaning such devices typically requires manually grabbing and removing the bacteria-laden obstructing material, which often includes entwined human hair.
[0006] Sinks in food preparation areas typically have devices for comminuting solid waste in order to allow its passage into a connected drain without clogging it. These devices are usually electrically powered “garbage disposals” that have little need for manual cleaning and operation, although they require significant space for installation, electrical power for operation, and adequate access for maintenance. These requirements are difficult or impossible to meet in the typical shower, tub, or sink outside the kitchen area.
[0007] Previous attempts to provide various manually operable drain strainers, waste traps, and comminuting devices, including comminuting or shearing devices designed to cut human hair, have various limitations. For example, Gandillon, U.S. Pat. No. 1,614,358, describes a manually operated device fitted under a common sink outlet, but the apparatus is prone to clogging, complex, and undesirably large. Comminution of solid material using such device is via manual rotation of a cone about a central axis against fixed arms.
[0008] Hammes, U.S. Pat. No. 2,012,680, describes an early incarnation of the electric garbage disposal flushing appropriately comminuted solid material from a grinding chamber by draining liquids through the chamber, and is shown as an under-sink installation.
[0009] Frank, U.S. Pat. No. 2,479,485, shows a manually operated self-cleaning sink stopper and addresses manual operation with solid waste straining and cutting functions. In the stopper device an initial strainer is included to keep commonly encountered material from reaching a cutting surface, and the initial strainer requires manual cleaning of materials trapped at that level. Furthermore, the device is prone to foriling with hair.
[0010] Hovartos, et al., U.S. Pat. No. 4,183,470, describes a garbage disposer that is driven by a water jet. The device requires significant space for installation and maintenance and has a vertically oriented shaft that is prone to fouling with hair. The device does not allow for manual operation when water flow provides insufficient power.
[0011] Maynard, Jr., U.S. Pat. No. 5,271,571, describes a water driven device for agitating and fragmenting debris in a sink drain. The device includes a hydraulically driven impeller that may also be manually engaged with the strainer basket. However, the central shaft is exposed to solid waste entering the drain, and is, therefore, prone to fouling.
[0012] Maynard, Jr., U.S. Pat. No. 5,141,166, discloses a device that includes a centrally mounted rotor, which rotates within a sink drain. However, the device is actuated by linear strokes of a steeply pitched threaded rod passing through a threaded bore of a rotor, and the threaded rod is exposed to solid waste material and is therefore prone to fouling.
[0013] Other devices, such as electric razors that are designed specifically to cut hair, are not easily adapted for use in handling hair caught on sink, tub, or shower drain parts to prevent Clogging of those drains. Ochiai et al., U.S. Pat. No. 4,549,352, and Szymansky, U.S. Pat. No. 5,901,446, describe cutting devices used in common electric shavers, but hair that has caught in sink, tub, or shower drains tends to be unlikely to be oriented so that these devices would be effective.
[0014] Lohnert, U.S. Patent Publication No. 2006/0207004, describes a device designed to rend captured hair in a drain orifice by integrating such a shearing device. However, hair trapped in the device is not perpendicularly oriented to the shearing surface. This dramatically decreases the efficacy of any shearing device as significant portion of the captured hair has a tendency to bind such a mechanism if not held perpendicular to the shearing motion.
[0015] The need for precisely machined and aligned shearing surfaces makes application to a legacy drain's cross members extremely difficult to achieve. This is especially true given the lack of standardization of the cross members. As such, their size, orientation, finish, and materials are highly variable, making the manufacture have to develop a separate device for the literally hundreds of different legacy drain permutations. Also, the use of such drain orifice cross members as strainer arms is not effective at catching a majority of hairs flowing into the orifice.
[0016] Materials and manufacturing costs are significant concerns of manufacturers in the plumbing field, thereby decreasing the likelihood that such a device would ever be cost effective enough to see market implementation. Use of shearing blades increases the costs beyond those in tuned with the alignment and precision issues as they require use of corrosion resistant materials, most likely ceramics, stainless steel, or other corrosion resistant yet durable alloys, with the concomitant cost issues associated with such materials. While mention is briefly made regarding use of plastics in this capacity, it is apparent to one skilled in the art of rending hair with a bladed instrument that plastic is not an effective alternative.
[0017] In any case, shearing surfaces requires precise machining and alignment in even non-legacy drain applications.
[0018] What is needed, therefore, is a device that is easily mounted in or constructed to fit in the space conventionally available in the strainer bowl or similar initial receptacle portion of a household drain, or constructed to replace such a strainer bowl or similar receptacle, for reducing the size of pieces of hair and other solid waste materials that might otherwise accumulate in and clog a drain conduit from household sink, tub, and shower drains, so as to promote more efficient disposal of the waste through the drain. Such a device should be manually operable with minimal physical effort of the operator, and resistant to clogs without needing frequent cleaning beyond that resulting from the operation of the device.
[0019] Finally, such a device should be designed as to be robust and easy to manufacture, without need for finely machined surfaces, blades, or knife-like edges.
[0020] The foregoing and other objectives, features, and advantages of the invention will be more readily understood upon consideration of the following detailed description of the invention taken in conjunction with the accompanying drawings.
SUMMARY OF THE INVENTION
[0021] The invention provides a device and method for preventing waste materials from clogging a household drain. The method comprises: a) receiving a quantity of waste material contained in a flow of liquid toward a drain receptacle; b) guiding the flow of liquid to a predetermined position adjacent a part of a manually operable device mounted within the drain receptacle and gathering the quantity of the waste material from the flow of liquid in a first location adjacent a member of the manually operable device located in the drain receptacle; c) maintaining the quantity of waste material generally perpendicular to the vertical motion of a manually moving size reduction assembly; d) manually moving the size reduction assembly portion of the device so as to subject the quantity of waste material to abrading action, thereby producing an abraded portion of waste material as a plurality of smaller pieces; and e) carrying the abraded pieces away from the drain receptacle and through a drain conduit in the flow of water.
[0022] In one embodiment the method includes the step of using the flow of water to align the quantity of waste material in a predetermined arrangement within the device prior to manually moving the size reduction assembly, which can be the arrangement of at least some of the waste materials into a strand.
[0023] In another embodiment, the method includes the step of using the flow of water to place the strand of waste material in a location spanning a plurality of neighboring water passages through a containment portion of the device.
[0024] In one alternative, the waste material is comminuted by moving the size reduction assembly downward, thereby urging a plurality of fingers into contact with the strand and into respective ones of the water passages, thereby tearing the strand into small pieces.
[0025] In one embodiment, the method includes the step of mechanically carrying a portion of the waste material along a roughened abrasive surface, thereby abrading the waste material into smaller pieces. In a further such embodiment, the method includes the step of mechanically carrying a portion of the waste material along a plurality of roughened abrasive surfaces.
[0026] In a different embodiment, a plurality of parts of a strand of the waste material is gripped while pushing the plurality of parts of the strand simultaneously into a plurality of respective apertures, thereby ripping the waste material into smaller pieces.
[0027] In a further preferred embodiment, the method includes the steps of gripping a strand of the waste material at a plurality of locations along a length of the strand while pushing a plurality of parts of the strand into a plurality of respective apertures, thereby ripping the waste material into smaller pieces.
[0028] In a still further preferred embodiment, the method includes the steps of simultaneously holding and pushing on a plurality of locations along a length of a strand of the waste material, thereby pushing the strand simultaneously into a plurality of neighboring apertures and thereby pulling and ripping the waste material into smaller pieces.
[0029] In another embodiment, the method includes the step of closing the drain by engaging the size reduction assembly with a part of the drain receptacle and thereby holding a sealing member carried on the size reduction assembly in sealing contact with a surface of the drain receptacle.
[0030] In a different embodiment, the method includes the step of closing the drain by using a spring included in the size reduction assembly to hold a sealing member carried on the size reduction assembly in sealing relationship with a surface of the drain receptacle. The size reduction assembly can thereafter be moved back to an initial position.
[0031] In a further preferred embodiment, the method includes gathering and entwining a plurality of hairs included in the waste materials as a part of the step of aligning the quantity of waste materials, and using the flow of water to align a strand of hairs transversely across the flow of water.
[0032] In a still further preferred embodiment, the method includes the step of gripping a strand of waste material at a plurality of places along the strand and thereafter forcing respective parts of the strand simultaneously into apart-spaced openings in a bottom member of the manually operable device, thereby elongating the strand sufficiently to cause it to break into a plurality of shorter pieces.
[0033] The invention also provides a manually operable device for use in a household drain inlet receptacle, the device comprising: (a) a stationary main body; (b) a strainer portion associated with the stationary main body and positioned to receive a flow of liquid and to catch relatively large pieces of solid waste material and temporarily hold the relatively large pieces at the strainer; (c) a manually movable size reduction assembly extending within the stationary main body and reciprocally movable with respect to the stationary main body, between an upper position and a lower position; and (d) an abrasive material associated with at least one of the stationary main body and the size reduction assembly; where when the manually movable size reduction assembly engages at least some of the relatively large pieces of waste material it acts cooperatively with the stationary main body to abrade and reduce at least some of the engaged pieces of waste material to a smaller size while the movable size reduction assembly is being moved between the upper and lower positions thereof.
[0034] The foregoing and other objectives, features, and advantages of the invention will be more readily understood upon consideration of the following detailed description of the invention taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] FIG. 1 is a perspective view of an idealized manually operable device for use in a drain.
[0036] FIG. 2 is a perspective view of the device shown in FIG. 1 with a movable size reduction assembly thereof moved to a lower position.
[0037] FIG. 3 is an exploded perspective view of the device shown in FIG. 1 at a reduced scale.
[0038] FIG. 4 is a cross section view of the device shown in FIG. 1 sitting within a legacy drain receptacle.
[0039] FIG. 5 is a perspective view of an alternative manually operable device for use in a drain.
[0040] FIG. 6 is a perspective view of the device shown in FIG. 5 with a movable size reduction assembly thereof moved to a lower position.
[0041] FIG. 7 is a cross-section view of the device shown in FIG. 5 sitting within a legacy drain receptacle.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0042] Referring first to FIGS. 1-4 , a manually operable dram mounted device 99 shown assembled in FIG. 1 may be installed in an open drain receptacle (as typified in FIG. 13 and seen in sink, bathtub, or shower drains) (add picture of common drain receptacle and label it FIG. 13 ) for disposal of solid materials commonly encountered in a household or office, other than in a kitchen, such as hair, thread, fingernails, soapy residues, and so forth.
[0043] Referring to FIG. 1 , the device 99 is in a ready condition, before operation, fitted for a typical drain receptacle. The device 99 may be manufactured in a size appropriate to fit snugly within the receptacle of a conventional drain for a tub, shower, or sink, in which the receptacle portion includes a horizontal bottom support cross member defining a threaded hole centered within the strainer bottom.
[0044] The device 99 includes a perforated strainer and ripping cutting plate 106 which is stationary and may be supported by a small distance above the horizontal bottom cross members of the receptacle, also shown in cross section in FIG. 4 . A movable size reduction assembly 100 includes vertically extending members hereinafter referred to as fingers 104 , arranged to move downwardly into respective ones of a set of corresponding holes 109 . Strands of hair and solids 107 are captured atop the radial arms 105 of strainer plate 106 .
[0045] FIG. 2 demonstrates depression of movable size reduction assembly 100 , leaving device 99 in a lower position that allows flexible flange 102 to interact with the top of drain receptacle and impede flow of liquid into drain receptacle, whereby plugging the drain. The holes 109 extending downward through the strainer plate 106 allow passage of fingers 104 during depression of movable reduction assembly 100 . Depression of movable size reduction assembly 100 pushes fingers 104 through holes 109 causing subsequent movement of solids captured atop radial arms 105 of the strainer plate 106 . The upper edges of the radial arms 105 are optimally roughened or coated with abrasive, as are the lower portion 108 of fingers 104 . Such optimization is key in abrasion and ripping of the moving strands of hair and captured solids 107 as movable size reduction assembly 100 is depressed, pulling hair and captured solids 107 across the abrasive and or roughened surfaces of 108 and upper portions of 105 . Movement of solids in said manner allows for rending of all solids across roughened and or abrasive coated surfaces. Flow of liquid through the strainer plate 106 in the course of normal use flushes the rendered hair and solids 114 into distal plumbing where it is now unlikely to contribute to clogs given their reduced size/length. Use of roughening and or abrasive coatings obviates the need for expensive and meticulously aligned shearing surfaces or cutting blades.
[0046] Experimental data has demonstrated that a solid strainer arm or protuberance every 0.31 inches of inside drain orifice circumference is necessary to capture 95% of hairs that are 4 inches in length or greater (the size of hairs shown in the experimental data to be the ones most prone to causing clogs in plumbing by wrapping around protuberances or defects in the plumbing encountering fluid stream flow).
[0047] Halving that strainer arm to circumference ratio to one strainer arm every 0.628 inches decreases the capture of hairs to as low as 48% of hairs entering the drain orifice (thereby allowing 52% of hairs to pass into distal plumbing and cause clog formation). Use of four cross members as shown in the prior art devices demonstrates a ratio of one strainer arm for every 1.7 inches of drain wall circumference (in the typical United States bath tub drain orifice diameter of 1.5 inches). It is clear that use of drain cross members (of which the typical number is 4 in legacy drains) to capture hair in the waste stream would allow a majority of hair to pass into distal plumbing, causing subsequent clogs.
[0048] A central support shaft/screw 200 as shown in FIG. 3 and FIG. 4 may be attached to the bottom cross member of the drain receptacle, and in most cases will be able to be threaded solidly into a mating relationship with the threaded hole. Legacy drain receptacles without a threaded cross member will not accept threaded shaft/screw 200 , and in such cases˜the screw/shaft 200 may be truncated, allowing strainer plate 106 to fit flush on cross members of the receptacle. In such a case, the outside edge of strainer plate 106 holds device 99 in place by fitting snuggly in the drain receptacle, perhaps with the aid of plumbers tape placed circumferentially around the base of strainer plate 106 . Alternatively, the manufacturer may decide to make strainer plate 106 integral to a drain receptacle.
[0049] The superior portion of strainer plate 106 defines a central opening 207 to receive the screw 200 , and to serve as a cover for spring 208 . The strainer base 106 may include two through-bores 210 to allow for drainage of liquid from within the spring cover.
[0050] A central body 103 has a generally cylindrical shape, and the vertically oriented fingers 104 (integral to the central body 103 ) extend parallel with one another and are spaced apart from each other about the cylindrical central body 103 . Each of the fingers 104 has a lower end portion 108 that extends downward independently and that have a rough or abrasive-coated surface aligned generally tangential to the circumference of the central body 103 . The lower end portion 108 of each finger is aligned with one of the correspondingly shaped holes 109 defined by the strainer plate 106 .
[0051] The central body 103 is hollow and has an open bottom end that fits around the superior portion of strainer plate 106 . An inner side of each finger 104 may be aligned with a corresponding groove 209 on the superior portion of strainer plate 106 in order to ensure proper guidance of fingers 104 through holes 109 in the lower portion of strainer plate 106 . The central body 103 is movable in a reciprocating manner upward and downward, between an upper position, in which the lower end portions 108 of the fingers 104 are located a small distance above the lower portion of strainer plate 106 and a lower position, in which all of the lower end portions extend downward into respective ones of the correspondingly shaped holes 109 in the lower portion of strainer plate 106 .
[0052] A scraping mechanism is enclosed within the upper portion of strainer plate FIG. 6 and the movable central body 103 and allows the size reduction assembly 100 to be moved downward and latched into its lower position by pressing downward on a cap 101 connected to the top of the central body 103 . The cap 101 has a comfortable upper surface that can comfortably be pressed by a hand or foot. The size reduction assembly 100 may then be released and raised to the upper position by a succeeding downward movement of the cap 101 and the attached central body 103 .
[0053] In one such stepping mechanism, as shown in FIGS. 3 and 4 , a hollow shaft 204 portion of the stepping mechanism is mounted over the upper end of the central support shaft 200 , allowing it to spin freely about the vertical axis of shaft 200 . Vertical ribs or flutes 210 on the outside of the hollow shaft 204 form a part of the stepping mechanism. Grooves defined between the flutes 210 receive inwardly projecting bodies 211 located within the upper end of the central body 103 , so that the hollow shaft 204 guides and aligns the upper end of the central body 103 With the central shaft 200 as the size reduction assembly 100 moves reciprocatingly upward and downward with respect to the strainer 106 and the central shaft 200 . An upper spring 201 and a lower spring 208 and a rotating stepping ratchet body 203 arranged in a well-known manner sequentially hold the central body 103 in its upper position and its lower position when it is repeatedly moved fully downward by depressing the cap 101 .
[0054] When the rotating stepping ratchet body 203 is in a lower position the upper spring 201 urges the central body 103 toward the lower position, and a seal member shown as a radially extending frustoconical resiliently flexible seal member 102 that fits around an upper shoulder of the central body 103 , is also lowered and urged toward the lower position. The seal member 102 then presses against the radially extending flange 115 of the drain receptacle portion 500 of the drain, preventing liquid from flowing into the device. When the central body 103 is in its upper position as shown in FIGS. 1 and 4 the seal member 102 is spaced upwardly apart from the flange 115 , and liquid to be drained from the tub or sink, etc., in which the device 99 is installed is free to enter a receptacle beneath the sealing member.
[0055] The cap 101 is held securely atop the central body 103 as by mating threads, and includes a lower rim 212 seated against a central hub of the sealing member 102 , so that to enter the drain liquid must pass through the device 99 , by flowing beneath the sealing member 102 , and then around the outside of the cylindrical portion of the central body 103 , between the fingers 104 , carrying any entrained waste solid pieces, including hair. Because the fingers 109 are straight and vertical, waste material can be carried unhampered to the strainer plate 106 in a flow of liquid.
[0056] As a flow of liquid containing solid pieces of waste material proceeds downward within a drain receptacle, past the stationary body of device 99 , pieces of solid waste come to sit atop the bottom portion of strainer plate 106 , and at least partially beneath the lower ends 108 of the fingers 104 , so that when the central body 103 is moved downward by pressure on the cap 101 the lower ends 108 of the fingers 104 grasp and force pieces of solid material through the corresponding holes 109 , abrading and ripping relatively large pieces of waste material 107 into reduced sized pieces 114 which are small enough to pass freely through a drain conduit beneath a drain receptacle with greatly reduced likelihood of accumulating so as to clog the associated drain conduit at a distant downstream location.
[0057] Even fibrous materials such as hair or pieces of grass will be divided into smaller pieces which are less likely to be able to accumulate within a drain conduit to a troublesome extent. As longer fibrous pieces such as long hairs 107 are carried into the space surrounding the central body 103 those fibers are carried down along the fingers 104 by the flow of water, which aligns such long pieces 107 naturally over the radial arms 105 of the lower portion of the strainer 106 as shown in FIG. 1 , and the abrasive coated or roughened bottom ends of the fingers 108 help to grasp such fibrous materials and urge spaced-apart portions of strands of entwined such hairs 107 simultaneously through neighboring ones of the corresponding holes 109 through the bottom plate 106 , thus ripping the hairs 107 or strands of other fibers into short pieces that when sufficiently shortened will drop through the holes 109 in the bottom plate 106 and thereafter be flushed from the device 99 into the flow of liquid into the drain conduit below the device.
[0058] Pieces of waste material which are not divided sufficiently with a first downward stroke of the size reduction assembly 100 can be further reduced by subsequent downward strokes of the size reduction assembly from its upper position to its lower position in which the lower ends of the fingers 104 pass into the boles 109 .
[0059] When the cap 101 is depressed far enough to move the central body 103 fully into its lower position the sealing member 102 engages the radially extending flange stopping the flow of liquid into the drain strainer, so that the device 99 seals the drain and retains liquid in the sink, shower, or bathtub in which it is installed, until the cap 101 and attached central body 103 are allowed to rise slightly and are thereafter again pushed downward, operating the stepping mechanism centrally located within the drain protective device 99 . The central body and the spring cover may fit together slidingly, and, although there is room for entry of water into the space deformed within the spring cover, the holes in the bottom of the spring cover allow the water to drain freely, and the space between the central body 103 and the spring cover 202 may be small enough to prevent entry of waste material that would be likely to interfere significantly with operation of the stepping mechanism.
[0060] While the entire device 99 could be of metal several parts could, instead, be of a suitable plastics material to reduce costs. Abrasive surfaces would ideally comprise of materials coated with abrasive material such as silicone carbide, but could also simply be roughened surfaces of the materials used to construct fingers 104 or radial arms 105 .
[0061] FIGS. 5 through 7 depict an alternative device 299 as a sink based device, utilizing the same basic technology as described above for a tub device in FIGS. 1-4 . FIG. 5 shows the device 299 in its up position, while FIG. 6 shows the embodiment in the down, or tearing, position. FIG. 7 depicts the device 299 fitted for a typical sink drain receptacle 500 .
[0062] In reference to FIGS. 5 and 7 , the device 299 includes a perforated strainer and ripping cutting plate 306 which is stationary and may be supported within the receptacle 500 . A movable size reduction assembly 300 includes vertically extending members hereinafter referred to as fingers 304 , arranged to move downwardly into respective ones of a set of corresponding holes 309 . Strands of hair and solids are captured atop the radial arms 305 of strainer plate 306 .
[0063] FIG. 6 show the position of a lowered assembly 300 . In the lower position of assembly 300 , the flexible flange 302 interacts with the top of the drain receptacle 500 to impede flow of liquid into drain receptacle 500 , whereby plugging the drain. The holes 309 extending downward through the strainer plate 306 allow passage of fingers 304 during depression of movable reduction assembly 300 .
[0064] In reference to FIG. 7 , the catch element 310 can be seen, depicted as a square opening at the bottom of the device to catch the lever that attaches to the plunger that directs the lowering and raising of the assembly 300 within the drain receptacle 500 . As a flow of liquid containing solid pieces of waste material proceeds downward past the raised assembly 300 , pieces of solid waste come to sit atop the bottom portion of strainer plate 306 , and at least partially beneath the lower ends 308 of the fingers 304 .
[0065] Referring again to FIG. 6 , when the assembly 300 is lowered downward the fingers 304 are pushed through holes 309 , causing subsequent movement of solids captured atop radial arms 305 of the strainer plate 306 . The upper edges of the radial arms 305 are optimally roughened or coated with abrasive, as are the lower portion 308 of fingers 304 . Such optimization is key in abrasion and ripping of the moving strands of hair and captured solids 307 as movable size reduction assembly 300 is depressed, pulling hair and captured solids 307 across the abrasive and or roughened surfaces of 308 and upper portions of 305 . Movement of solids in this manner allows for rending of all solids across roughened and or abrasive coated surfaces.
[0066] Flow of liquid through the strainer plate 306 in the course of normal use flushes the rendered hair and solids into distal plumbing. As is the case for the embodiment of FIGS. 1-4 , the use of roughening and or abrasive coatings obviates the need for expensive and meticulously aligned shearing surfaces or cutting blades.
[0067] Pieces of waste material which are not divided sufficiently with a first downward stroke of the size reduction assembly 300 will be further reduced by subsequent downward strokes of the size reduction assembly from its upper position to its lower position in which the lower ends of the fingers 304 pass into the holes 309 .
[0068] The devices described in Non-Provisional Patent Application No. 20070290082 describe the use of strategically placed abrasive materials or roughened surfaces to achieve the desired function without the use of shearing. This patent application is meant to expound upon those described benefits by describing exemplary devices utilizing the primary features of trapping of solid materials from a liquid flow, aligning them in an orientation that facilitates their rending, then rending them into small pieces unlikely to form clogs by a movable drain assembly with strategically placed abrasives or roughened surfaces.
[0069] Thus, the present disclosure sets forth a description of a manually operable apparatus and a method for separating larger pieces of materials such as human hair, textile fibers, bits of grass or other vegetation, fingernails, toenails, and other waste materials from a flow of water being drained from a conventional fixture such as a bathtub, shower, or sink, and for periodically reducing the size of such accumulated pieces of waste materials to a size small enough to be flushed readily down through an ordinary drain conduit without accumulating readily in quantities able to cause a significant blockage of such a drain conduit. Key to the function of the device is the movement the materials against at least one abrasive or sufficiently roughened surface at strategic locations that rend hair into smaller pieces when the plunger arms of the device are actuated. Use of abrasives or sufficiently roughened surfaces instead of shearing to rend hair allows for more extensive use of plastics as blades and hard cutting surfaces aren't necessary, makes the device easier to manufacture for placement in a multitude of legacy drains, and significantly reduces the manufacturing and materials costs associated with machining or casting of the metal/ceramic/alloy parts necessary to produce shearing surfaces.
[0070] Abrasion of materials to the point that they can no longer resist breaking as they are stretched by the actuation of at least one moving plunger arm is significantly different from shearing. Abrasion of materials commonly encountered in bathroom drains, necessitates that the materials move across at least one abrasive or sufficiently roughened surface in order to facilitate their rending into smaller pieces. Shearing, in contrast, requires that the materials be relatively immobile so that it may remain in between the two shearing surfaces and be cut.
[0071] Likewise, though a perpendicular orientation of the material in relation to the movement of plunger arms at the beginning of device actuation is preferred, the orientation of the materials during the actuation of the plunger arms can be variable. This contrasts with materials in a shearing device that must ideally remain strictly perpendicular to the shearing surfaces to avoid simply binding the surfaces to a point where their mobility is hindered as one might encounter with hair binding the blades of scissors if the hair isn't held taut and perpendicular to the scissor blade action.
[0072] Finally, though abrasive materials and roughened surfaces tend to have sharp edges on a microscopic level, and may indeed do some cutting, they are variably oriented so as to facilitate rending of materials with variable orientations. This, again, contrasts with shearing where the sharp shearing surface is in a roughly linear orientation, thus requiring that the material to be cut again be in roughly a perpendicular orientation to the motion of the blades.
[0073] In some embodiments the device is easily installed in an existing drain. Other embodiments may be manufactured as integral parts of drain receptacles to be mounted in a sink, tub, or shower.
[0074] The simplicity of the drain mounted device allows for easy production and installation, garnering significant advantages over more complex mechanisms such as motor-driven garbage disposals, or those requiring machined and corrosion resistant shearing surfaces.
[0075] The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding equivalents of the features shown and described or portions thereof; it being recognized that the scope of the invention is defined and limited only by the claims which follow. | A method for preventing waste materials from clogging a household drain, the method comprising: a) receiving a quantity of waste material contained in a flow of liquid toward a drain receptacle; b) guiding the flow of liquid to a predetermined position adjacent a part of a manually operable device mounted within the drain receptacle and gathering the quantity of the waste material from the flow of liquid in a first location adjacent a member of the manually operable device located in the drain receptacle; c) maintaining the quantity of waste material generally perpendicular to the vertical motion of a manually moving size reduction assembly; d) manually moving the size reduction assembly portion of the device so as to subject the quantity of waste material to abrading action, thereby producing an abraded portion of waste material as a plurality of smaller pieces; and e) carrying the abraded pieces away from the drain receptacle and through a drain conduit in the flow of water. | 4 |
TECHNICAL FIELD
The present invention relates to equipment for servicing oil and gas wells and, in particular, to an apparatus and method for securing a mandrel of a well tool in an operative position in which the mandrel is packed-off against a fixed-point in the well.
BACKGROUND OF THE INVENTION
Most oil and gas wells eventually require some form of stimulation to enhance hydrocarbon flow and make or keep them economically viable. The servicing of the oil and gas wells to stimulate production requires the pumping of fluids under high pressure. The fluids are generally corrosive and abrasive because they are frequently laden with corrosive acids and abrasive proppants such as sharp sand. Consequently, such fluids can cause irreparable damage to wellhead equipment if they are pumped directly through the spool and the various valves that make up the wellhead. To prevent such damage, wellhead isolation tools have been used and various configurations are well known in the art.
A general principle of wellhead isolation in the prior art is to insert a mandrel of the tools through the various valves and spools of the wellhead to isolate those components from the elevated pressures and the corrosive and abrasive fluids used in the well treatment to stimulate production. A top end of the mandrel is connected to one or more high pressure valves through which the stimulation fluids are pumped. A packoff assembly is usually provided at a bottom end of the mandrel for achieving a fluid seal against the inside of the production tubing or casing so that the wellhead is completely isolated from the stimulation fluids. The length of the mandrel need not be precise because the location of the packoff assembly in the production tubing or casing is immaterial so long as the mandrel is inserted into the production tubing or casing and a fluid tight seal is achieved between the production tubing or casing and the packoff assembly.
However, a packoff affixed to a bottom end of the mandrel which seals against the inside of the production tubing or casing, limits the internal diameter of the mandrel and, consequently, the flow rate at which stimulation fluids may be pumped into the well. To overcome this problem, applicant invented an improved mandrel for a wellhead isolation tool described in co-pending U.S. patent application Ser. No. 08/837,574 which was filed on Apr. 21, 1997 and entitled APPARATUS FOR INCREASING THE TRANSFER RATE OF PRODUCTION STIMULATION FLUIDS THROUGH THE WELLHEAD OF A HYDROCARBON WELL. The apparatus described in that patent application includes a mandrel for a wellhead isolation tool and a tubing hanger for use in conjunction with the mandrel. The mandrel includes an annular seal bonded to an outside wall above the bottom end of the mandrel. The annular seal cooperates with a sealing surface in the top end of the tubing hanger to isolate the wellhead equipment from high pressures and corrosive and abrasive materials pumped into the well during a well treatment to stimulate production. The novel construction of the mandrel and the tubing hanger eliminates the requirement for a packoff assembly attached to the bottom of the mandrel and thereby permits the mandrel to have a larger internal diameter for increasing the transfer rate of the production stimulation fluids through the wellhead. The axial length of the sealing surface in the tubing hanger available for packoff is limited and, therefore, the length of the mandrel is determined, to a large extent, by a distance from the top of the tubing hanger to the top of the wellhead.
Applicant describes another improved mandrel for a wellhead isolation tool in U.S. patent application Ser. No. 09/356,231 which was filed on Jul. 16, 1999 and entitled WELLHEAD ISOLATION TOOL AND METHOD OF USING SAME, which is incorporated herein by reference. The wellhead isolation tool includes a mandrel that is inserted into a wellhead. The mandrel is seated against an annular step above back pressure valve threads in a tubing hanger to isolate the pressure sensitive components of the wellhead from fluid pressure used in the well treatment and has a lower section extending past the back pressure valve threads and tubing threads into the tubing to protect the threads from washout. The annular step above the back pressure valve threads in the tubing hanger is a fixed-point for packoff of the mandrel and, therefore, a length of the mandrel is determined by the distance from the annular step to the top of the wellhead and a lockdown mechanism for securing the wellhead isolation tool to the wellhead preferably provides a range of adjustment to compensate for variations in the position of the top end of the mandrel when the mandrel is packed off in different wellheads.
Another example of a well tool in an operative position in which the mandrel of the well tool is packed-off against a fixed-point in the well is described in Applicant's U.S. Pat. No. 5,819,851 which issued on Oct. 13, 1998 and is entitled BLOWOUT PREVENTER PROTECTOR FOR USE DURING HIGH PRESSURE OIL/GAS WELL STIMULATION. The blowout preventer protector described in that patent includes a mandrel that is forcibly reciprocatable in an annular cavity of a spool. The mandrel is stroked down through a blowout preventer and packed off at the bottom end against a bit guide that is attached to a top end of the casing to protect the blowout preventer from exposure to fluid pressure as well as abrasive and corrosive well stimulation fluids. The bit guide attached to the top end of the casing provides a fixed-point for packoff of the mandrel.
It is apparent from the examples described above that, as a result of new tools being invented and new technology being developed, there is a need for a lockdown mechanism for securing a well tool requiring a fixed-point packoff in an operative position in the well.
The blowout preventer protector described in U.S. Pat. No. 5,819,851 includes a mandrel that is integrally incorporated with a hydraulic setting tool. The mandrel is not separable from the hydraulic setting tool and the setting tool is used to hydraulically lock the mandrel in an operative position. The mandrel. can be secured at any location within the annular cavity by maintaining the hydraulic pressure in the annular cavity after the mandrel is packed-off against the bit guide. The stroke of the hydraulic setting tool is used for inserting the mandrel through the blowout preventer, and also provides compensation for variations in a distance from the bit guide to the top of the blowout preventer when the mandrel is inserted through different wellheads. The blowout preventer protector is widely accepted in the industry and the hydraulic setting tool is very convenient for securing a mandrel of a well tool in the operative position requiring fixed-point packoff in the well. However, the setting tool must be fairly long to provide sufficient stroke. Furthermore, the setting tool is not removable from the mandrel during a well treatment to stimulate production. Consequently, the blowout preventer protector has a high profile. A well tool with a high profile is not convenient because access to equipment mounted thereto, such as a high pressure valve, is impeded by the height of the valve above ground. In addition, a hydraulic lockdown mechanism is considered less secure than a mechanical lockdown mechanism. The hydraulic lockdown mechanism is dependent on maintenance of the hydraulic fluid pressure in the setting tool. Since fluid pressure may be lost for a variety of reasons, persons in the industry are generally less inclined to endorse or accept a hydraulic lockdown mechanism.
A mechanical lockdown mechanism having a range of adjustment is used for the well tools described in Applicant's co-pending U.S. patent application filed on Jun. 23, 1999 and the application filed on Jul. 16, 1999 referenced above. The mechanical lockdown mechanism described in the above two patent applications is for securing a mandrel of well tools in an operative position requiring fixed-point packoff in the well, and provides a broad range of adjustment to compensate for variations in the height of different wellheads to which the well tool is mounted. The mechanical lockdown mechanism includes a base member that is adapted to be mounted to a top of the wellhead, the base member having a central passage to permit the insertion and the removal of the mandrel. The passage is surrounded by an integral sleeve having an elongated spiral thread for engaging a lockdown nut that is adapted to secure the mandrel in the operative position. The spiral thread on the integral sleeve and the lockdown nut have a length adequate to ensure safe operation at well stimulation fluid pressures. At least one of the spiral threads on the integral sleeve and the lockdown nut has a length adequate to provide a significant range of adjustment to compensate for variation in a distance between the top of the wellhead and the fixed-point for packoff in the well when the tool is mounted to different wellheads. The mechanical lockdown mechanism is separated from the hydraulic setting tool and, therefore, permits the setting tool to be removed from the well tool after the mandrel is locked down in the operative position. The tools therefore provide a low profile to facilitate well stimulation operations. The advantages also include the security of a mechanical lockdown mechanism. Therefore, there exists a need for a lockdown mechanism for securing a mandrel of a well tool in an operative position requiring fixed-point packoff in the well which provides a broader range of adjustment while ensuring a secure mechanical lockdown for maximum security.
SUMMARY OF THE INVENTION
It is a primary object of the invention to provide a lockdown mechanism for securing a mandrel of a well tool in an operative position in which the mandrel is packed-off against a fixed-point in the well.
It is another object of the invention to provide a lockdown mechanism for securing a mandrel of the well tool in an operative position requiring fixed-point packoff in the well, the lockdown mechanism having a low profile for easy access to a high pressure valve during use while the tool is in the operative position.
It is a further object of the invention to provide a lockdown mechanism for securing a mandrel of the well tool in an operative position requiring fixed-point packoff in the well which is convenient to use.
It is yet a further object of the invention to provide a lockdown mechanism for securing a mandrel of a well tool in an operative position requiring fixed-point packoff in the well which combines a hydraulic lockdown mechanism with a mechanical lockdown mechanism.
In accordance with one aspect of the invention, there is provided an apparatus for securing a mandrel of a well tool in an operative position requiring fixed-point packoff in the well, comprising a first and a second lockdown mechanism arranged so that the mandrel is locked in the operative position only when both the first and the second lockdown mechanisms are in respective lockdown positions; the first lockdown mechanism adapted to detachably maintain the mandrel in proximity to the fixed-point packoff when in the lockdown position, the first lockdown mechanism including a base member for connection to a wellhead of the well and a locking member for detachably engaging the base member; and the second lockdown mechanism having a range of adjustment adequate to ensure that the mandrel can be moved into the operative position and locked down in the operative position while the first lockdown mechanism is in the lockdown position.
The second lockdown mechanism preferably comprises a first member connected to the mandrel and a second member connected to the locking member of the first lockdown mechanism, the first and second members being linked to permit movement with respect to each other within the range of adjustment.
In accordance with one embodiment of the invention, the second member of the second lockdown mechanism includes at least one threaded bolt connected at a fixed end to the locking member of the first lockdown mechanism and the first member of the second lockdown mechanism has at least one bore to permit the at least one threaded bolt to pass therethrough without resistance, the at least one threaded bolt being prevented from being withdrawn from the bore by a lock nut which is adapted to be rotated from a free end of the threaded bolt towards the fixed end to lock the second lockdown mechanism in the lockdown position.
In accordance with another embodiment of the invention, the first member of the second lockdown mechanism includes a piston fixed to the mandrel and the second member of the second lockdown mechanism includes a cylinder connected with the locking member of the first lockdown mechanism, the piston being adapted to be reciprocated within the cylinder using fluid pressure.
In accordance with another aspect of the invention, there is provided an apparatus used for securing a mandrel of a well tool in an operative position in which the mandrel is packed off against a fixed-point in the well, comprising a mechanical lockdown mechanism for detachably securing the well tool to a wellhead of the well and maintaining the mandrel in proximity to the fixed-point for packoff, the mechanical lockdown mechanism including a base member for connection of the wellhead and a locking member for detachably engaging the base member; a hydraulic mechanism including a cylinder and a piston which may be reciprocated within the cylinder using fluid pressure, the cylinder being connected to the locking member of the mechanical lockdown mechanism and the piston being fixed to the mandrel of the tool so that the mandrel may be moved to and maintained in the operative position by injecting fluid pressure into the cylinder while the mechanical lockdown mechanism is in a lockdown position. The hydraulic mechanism preferably comprises a mechanical locking mechanism to ensure the mandrel is maintained in the operative position in the event that the fluid pressure is lost.
The invention provides a lockdown mechanism with a greater range of adjustment for securing a mandrel of a well tool in an operative position requiring fixed-point packoff in the well, in comparison with prior art lockdown mechanisms. Consequently, the length of a mandrel may be less precisely matched to a distance from the fixed-point for packoff to the top of the wellhead. Other features and advantages will become apparent given the preferred embodiments which are described below.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be further explained by way of example only and with reference to the following drawings, in which:
FIGS. 1 to 4 illustrate cross-sectional views of an apparatus in various working positions in accordance with a preferred embodiment of the invention;
FIGS. 5 to 7 illustrate cross-sectional views of an apparatus in various working positions in accordance with another preferred embodiment of the invention;
FIG. 8 is a schematic diagram of the apparatus shown in FIG. 5 mounted to a blowout preventer through which a mandrel is to be stroked and secured in an operative position in which the mandrel is packed off against a bit guide mounted to a top of a casing of the well; and
FIG. 9 is a schematic diagram of the apparatus shown in FIG. 1 mounted to a wellhead through which a mandrel is to be stroked and secured in an operative position in which the mandrel is packed off against an annular step in a tubing hanger of the wellhead.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a cross-sectional view of a first lockdown mechanism 20 for securing a mandrel 22 of a well tool in an operative position in which the mandrel 22 is packed off against a fixed-point 24 in the well. The fixed-point for packoff may be a bit guide mounted to the top of a casing, as shown in FIG. 8, an annular step above back pressure valve threads of a tubing hanger, as shown in FIG. 9, or any other type of fixed-point location used for packoff in a wellhead, a casing, a tubing or a downhole tool. For the purpose of convenient description, the mandrel is assumed to be packed off against a fixed packoff point at the bottom of FIGS. 1 through 7.
The apparatus 20 includes a mandrel head 26 connected to a top end of the mandrel 22 and a base plate 28 mounted to a top of the wellhead, which is indicated by line 30 . The mandrel head 26 is separable from the base plate 28 to permit the mandrel 22 , which is connected to the mandrel head 26 , to be inserted through the base plate 28 into the wellhead until the mandrel 22 reaches a fixed-point 24 for packoff. In different wellheads, a distance “D” from the fixed-point 24 for packoff to the top of the wellhead may vary. Although a length “L” of the mandrel 22 may be adjusted by the insertion of extension sections, as described in Applicant's co-pending patent applications, it is not practical to provide a large number of extension sections, each having a different length to permit mandrels to be assembled to precisely match the distance “D” of each wellhead. A distance “d” from a top of the wellhead 30 to a top end of the mandrel 22 is a constant when the mandrel 22 is locked down to the base plate 28 by a first locking member 38 , as shown in FIG. 1 . Consequently, a range of adjustment “B” is provided by a second locking member such that “B” is greater than a distance “C” between a bottom end of the mandrel 22 and the fixed packoff point 24 when the mandrel 22 is locked down to the base plate 28 , as shown in FIG. 1 .
The base plate 28 is preferably a circular disc which includes an integral concentric sleeve 32 perpendicular to the base plate 28 . A spiral thread 34 on the exterior of the integral sleeve 32 mates with a complementary spiral thread 36 on an interior surface of a lockdown nut 38 . The base plate 28 and the integral sleeve 32 include a central passage 40 to permit the mandrel 22 to pass through. The lockdown nut 38 includes a top wall 42 for rotatably retaining a connector 44 . The connector 44 is a cylindrical body with an upper flange 46 and a lower flange 48 which engages the top wall 42 of the lockdown nut 38 . A central passage 50 through the connector 44 permits the mandrel 22 to fully pass through. The mandrel head 26 is a cylindrical body with an upper flange 52 for connection of equipment, such as a high pressure valve, and a lower flange 54 which is adjustably linked to the connector 44 . The adjustable link between the connector 44 and the mandrel head 26 is provided by at least two threaded bolts 56 which extends through at least two respective bores 58 in the lower flange 54 . The threaded bolts 56 are connected at their fixed ends to the upper flange 46 of the connector 44 . Nuts 60 at a free end of each bolt 56 prevents the bolt from being withdrawn from the flange 54 . The bore 58 has an internal diameter slightly larger than an external diameter of the bolt 56 to permit the bolt 56 to pass therethrough without resistance. The threaded bolt 56 has an adequate length to permit the range “B” of movement of the mandrel head 56 relative to the connector 44 .
When the lockdown nut 38 is locked to the integral sleeve 32 by the engagement of threads 34 , 36 and the mandrel head 26 is moved towards or away from the connector 44 within the range “B”, the mandrel can be packed off against a fixed-point for packoff. Therefore, when the mandrel 22 may be used with wellheads having different configurations and the distance D from the fixed-point 24 for packoff to the top of the wellhead indicated by line 30 varies by a distance “C” that is not greater than the range of adjustment “B”, that is, 0≦C≦B, the apparatus 20 is adapted to be locked down in the operative position in which a bottom end of the mandrel 22 is packed off against the fixed-point 24 for packoff.
As will be understood by those skilled in the art, in order to safely restrain fluid pressure during a well treatment to stimulate production, the number of the threaded bolts 56 , nuts 60 and bores 58 is generally more than two. The bolts 56 are circumferentially spaced from each other, the number of each being dictated by the fluid pressures to be restrained and the quality of materials used. The periphery of the lower flange 54 of the mandrel head 26 extends beyond the flange 52 of the mandrel head 26 so that the upper flange 52 does not interfere with the threaded bolts 56 as the mandrel head 26 is moved towards the connector 44 . The mandrel head 26 has a central passage 62 in fluid communication with the mandrel 22 . The passage 62 has a diameter not smaller than the internal diameter of the mandrel 22 for a full access to the mandrel. A spiral thread is provided at the lower end of the central passage 62 for connection of the threaded top end of the mandrel 22 . A sealing mechanism (not shown) is provided in the threaded connection between the top end of the mandrel 22 and the mandrel head 26 to prevent well fluids from escaping to atmosphere. The central passage 40 through the base plate 28 has a recessed lower region for receiving a steel spacer 64 and packing rings 66 preferably constructed of brass, rubber and fabric. The steel spacer 64 and packing rings 66 define a passage of the same diameter as the periphery of the mandrel 22 . The steel spacer 64 and the packing rings 66 are removable and may be interchanged to accommodate different sizes of mandrel 22 . The steel spacer 64 and the packing rings 66 are retained in the recessed region by a retainer nut 68 . The combination of the steel spacer 64 , packing rings 66 and the retainer nut 68 provide a fluid seal to prevent the passage to atmosphere of well fluids between the exterior of the mandrel 22 and the interior of the wellhead when the mandrel 22 is inserted into the wellhead.
FIG. 2 shows a cross-sectional view of the apparatus 20 in a working position in which the nuts 60 are at the free end of the threaded bolts 56 and the lockdown nut 38 is disengaged from the base plate 28 . In this condition, the base plate 28 can be mounted on the top of the wellhead while the other parts of the apparatus 20 are connected to the top end of mandrel 22 and are moved with the mandrel 22 when the mandrel 22 is inserted into the wellhead by a setting tool, which will be described in more detail with reference to FIGS. 8 and 9. When the apparatus 20 , except for the base plate 28 , is moved downwardly as the mandrel 22 is inserted through the wellhead, the upper flange 46 of the connector 44 is spaced from the lower flange 54 of the mandrel head 26 , as shown in FIG. 2 . For safe engagement to restrain the high fluid pressures during a well treatment to stimulate production, threads 34 - 36 are engaged a distance “A” by rotating the lockdown nut 38 . At this stage, the bottom end of the mandrel 22 is still above the fixed-point 24 for packoff by the distance “C”, as shown in FIG. 1 . After the lockdown nut 38 is fully engaged as shown in FIG. 3, the mandrel 22 is further stroked down until the bottom end of the mandrel 22 packs off against the fixed-point 24 . The nuts 60 are then rotated down against the lower flange 54 of the mandrel head 26 to prevent a fluid seal on the lower end of mandrel 22 (not shown) from being forced away from the fixed-point 24 for packoff after the setting tool is removed from the wellhead and pressurized fluids are injected into the well.
Alternatively, the mandrel 22 with connected mandrel head 26 may be stroked downwardly without engaging the lockdown nut 38 with the base plate 28 as shown in FIG. 4 until the bottom end of the mandrel 22 is packed off in an operative position against the fixed-point 24 for packoff. The lockdown nut 38 is then rotated to engage the threads 34 on the integral sleeve 32 . The final locked position is the same as shown in FIG. 3 . Therefore, the nuts 60 are turned down against the lower flange 54 of the mandrel head 26 to lock the apparatus 20 in the operative position.
FIG. 5 is a cross-sectional view of an apparatus 70 in accordance with another preferred embodiment of the invention. The apparatus 70 includes a mandrel head 26 threadedly connected to a top end of the mandrel 72 and a base plate 28 adapted to be mounted to the top of the wellhead, indicated by line 30 . The mandrel head 26 , base plate 28 and other parts indicated by reference numerals corresponding to those shown in FIG. 1 are respectively identical to the corresponding parts of the apparatus 70 . The principal difference is that the apparatus 70 includes an integral hydraulic cylinder 74 in place of the connector 44 of the apparatus 20 . The hydraulic cylinder 74 includes upper and lower walls 76 , 78 which respectively surround the mandrel 72 . The cylinder 74 further includes a sidewall 80 which defines an annular cavity 82 . A piston 84 is fixed to the mandrel 72 . O-ring seals 86 are provided respectively between the piston 84 and sidewall 80 , upper wall 76 and the lower wall 78 and the exterior surface of a mandrel 72 to permit introduction of pressurized hydraulic fluid into the annular cavity 82 to induce movement of the piston 84 . The hydraulic fluid is injected, as required, through an upper port 88 and drained through a lower port 90 , and vice versa. The piston preferably has a stroke about equal to the distance “B”, to match the functional length of the threaded bolts 56 . The threaded bolts 56 are connected at their fixed ends to the upper wall 76 . The cylinder 74 further includes a connecting flange 92 connected to but spaced from the lower wall 78 for rotatable engagement with the top wall 42 of the lockdown nut 38 .
FIG. 6 is a cross-sectional view of the apparatus 70 shown in FIG. 5 with the piston 84 at the top of cylinder 74 , and the lockdown nut 38 disengaged from the integral sleeve 32 of the base plate 28 . As described above, the base plate 28 is mounted to the top of the wellhead before the mandrel 72 is inserted into the wellhead. The mandrel 72 is stroked down under a force P 1 exerted by a setting tool, as will be described below with reference to FIGS. 8 and 9. The piston 84 is maintained at a top of the hydraulic cylinder by a force P 2 exerted by pressurized hydraulic fluid trapped in the cylinder. The lockdown nut 38 is turned down to its locked position as shown in FIG. 5 . The bottom end of the mandrel 70 is then a distance “C” above the fixed-point 24 for packoff.
After the lockdown nut 38 is fully engaged with the base plate 28 , the setting tool is removed from the wellhead and the well tool is left unobstructed for access. Pressurized hydraulic fluid is injected into the upper port 88 of the cylinder 74 while the hydraulic fluid below the piston 84 is drained from the lower port 90 so that the mandrel 72 is forced downwardly to packoff against the fixed-point 24 under a force P 2 exerted on the piston 84 by the pressurized hydraulic fluid, as shown in FIG. 7 . The mandrel head 26 is thus forced downwardly over the distance “C” so that the space between the mandrel head 26 and the upper wall 76 of the cylinder 74 is reduced to B-C. The mandrel 72 is locked down in its operative position by the hydraulic force P 2 . To ensure that the mandrel is secured in the operative position, the nuts 60 are turned down against the lower flange 54 of the mandrel head 26 .
FIG. 8 shows an example of the use of the apparatus 70 shown in FIG. 5, using a hydraulic setting tool 93 to insert the mandrel 72 to an operative position for a well treatment to stimulate production. In this example, the mandrel 72 is used to protect a blowout preventer 100 and includes a packoff assembly 94 that is packed-off against a top of a bit guide 96 mounted to a top of a casing 98 , as described in Applicant's co-pending patent application filed Jun. 23, 1999. The hydraulic setting tool 93 illustrated in FIG. 8 is also described in Applicant's U.S. Pat. No. 4,867,243 which issued on Sep. 19, 1989 and is entitled WELLHEAD ISOLATION TOOL AND SETTING TOOL AND METHOD OF USING SAME, which is incorporated herein by reference. The blowout preventer 100 is connected to the well casing 98 by various spools, such as a tubing head spool 102 , for example. The blowout preventer 100 and the tubing head spool 102 are wellhead equipment that is well known in the art and their construction and function do not form a part of this invention. The blowout preventer 100 and the tubing head spool 102 are, therefore, not described. The apparatus 70 is supported on a top of the blowout preventer by mounting the base plate 28 in a fluid tight relationship to the top flange of the blowout preventer 100 . Mounted above the apparatus 70 , is a high pressure valve 104 which is used for fluid flow control during a well treatment to stimulate production and, also used to prevent well fluids from escaping to the atmosphere from the top of the mandrel 72 . The high pressure valve 104 is typically a hydraulic valve well known in the art. The hydraulic setting tool 93 includes a hydraulic cylinder 106 which is mounted to a support plate 108 . The support plate 108 includes a central passage (not shown) to permit a piston rod 114 of the hydraulic cylinder 106 to pass through the support plate 108 . The support 108 also includes at least two attachment points 110 for attachment of respective hydraulic cylinder support rods 112 . The spaced apart attachment points 110 are preferably equally spaced from the central passage to ensure that the hydraulic cylinder 106 and the piston rod 114 align with the blowout preventer 100 . The hydraulic cylinder support rods 112 are respectively attached at their lower ends to corresponding attachment points 116 on the base plate 28 . As is apparent, the base plate 28 and the support plate 108 have a periphery that extends beyond the wellhead to provide enough radial offset of the cylinder support rods 112 to accommodate the high pressure valve 104 , the mandrel head 26 and the cylinder 74 . The support rods 112 are identical in length. The support rods 112 are attached to the respective spaced apart attachment points 110 , 116 on the support plates 108 and the base plate 28 by means of threaded fasteners or pins (not illustrated). The piston rod 114 is attached to the top of the high pressure valve 104 by a connector 118 so that a force can be applied to stroke the mandrel 72 down through the wellhead.
After the mandrel 72 is stroked downwardly to an extent that the packoff assembly 94 is in proximity to the bit guide 96 , and the lockdown nut 38 is turned down to its locked position, as illustrated in FIG. 8, the setting tool 93 including the hydraulic cylinder 106 , support plate 108 , cylinder support rods 112 and the connector 118 are removed. The packoff assembly 94 on the bottom of the mandrel 72 is then stroked further down until it is packed off against the bit guide 96 by injecting pressurized fluid into the top port 88 of the hydraulic cylinder 74 , as illustrated in FIG. 7 .
FIG. 9 shows an example of the use of the apparatus 20 , shown in FIG. 1, using the hydraulic setting tool 93 to insert the mandrel 22 to an operative position for a well treatment to stimulate production. In this example, the wellhead is constructed in a well known manner from a series of valves and related flanges. The wellhead schematically illustrated in FIG. 9 includes a tubing spool 120 which receives and supports a tubing hanger 122 . Connected by flange connections to the top of the tubing spool 120 , are valves 124 and 126 . The purpose of the two valves 124 and 126 is to control the flow of hydrocarbons from the well. The apparatus 20 is mounted above the wellhead, that is, atop the valve 126 . The mandrel 22 is inserted through the wellhead into the operative position in which an elastomeric seal (not shown) on a sealing shoulder 128 is seated against an annular step 130 located above back pressure valve threads 132 of the tubing hanger 122 while a lower section of the mandrel 22 enters the top of the tubing 134 to protect the back pressure valve threads 132 and tubing threads 136 , as described in Applicant's co-pending patent application filed Jul. 16, 1999. The annular step 130 of the tubing hanger 122 is the fixed-point 24 for packoff in the well. The distance from the annular step 130 to the top of the valve 126 may vary in different wellheads and, therefore, the apparatus 20 is used to provide a broad range of adjustment to compensate for variations to ensure that the mandrel 22 can be locked down in the operative position. After the setting tool 93 is mounted to the base plate 28 in the same way as described with reference to FIG. 8, the steps described with reference to FIGS. 1 to 4 are followed to lock the mandrel 22 in the operative position in which the elastomeric seal on the sealing shoulder 128 of the mandrel 22 is packed-off against the annular step 130 .
The two examples described with reference to FIGS. 8 and 9 are for the purpose of illustration of the invention only and do not limit the applications of the invention. For example, the two embodiments described above may be used interchangeably. Likewise, other setting tool known in the art may be used in conjunction with the apparatus 20 or 70 for inserting the mandrel through the wellhead into proximity of the operative position. For example, a setting tool described by McLeod in U.S. Pat. No. 4,632,183 and entitled INSERTION DRIVE SYSTEM FOR TREE SAVERS which issued on Dec. 5, 1984, the entire specification which is incorporated herein by reference, may be used. Another type of setting tool which may also be used to insert the mandrel in proximity to the operative position is described by Bullen in U.S. Pat. No. 4,241,786, entitled WELLTREE SAVER which issued on May 2, 1979 and is also incorporated herein by reference.
It should also be understood that the apparatus described above can be used to lock down other types of tools which must be packed-off against a fixed-point in a well and is not limited to use with the mandrels described above.
Modifications and improvements to the above-described embodiments of the invention may become apparent to those skilled in the art. The foregoing description is intended to be exemplary rather than limiting. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims. | An apparatus for securing a mandrel of a well tool in an operative position in which the mandrel is packed off against a fixed-point in the well is described. The apparatus includes a mechanical lockdown mechanism to secure the tool to the wellhead and maintain the mandrel in proximity to the fixed-point for packoff, and a mechanical or a hydraulic mechanism to move the mandrel into the operative position while the mechanical lockdown mechanism is in a lockdown position. A second mechanical locking mechanism is provided to ensure the mandrel is maintained in the operative position in the event that hydraulic pressure is lost. The invention provides a mechanism to lock down well tools requiring fixed-point packoff in a well and advantageously improves the range of adjustment of the lockdown mechanism so that the length of a mandrel may be less precisely matched to a distance from a top of the wellhead to the fixed-point in the well. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application incorporates by reference in its entirety and claims priority to U.S. Provisional Application 60/484,866, filed Jul. 3, 2003, by inventor Philip Charron.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention is directed to equipment venting apparatus and techniques and to an installation kit for installing equipment venting, and particularly in-wall dryer venting.
2. Description of Related Art
Technique for venting automatic clothes dryers through a wall to the external environment are well known in the art. However, use of this technique often requires that a laundry room abut against an external wall. This constrains the design of the home or building in which the dryer is to be placed and, when a laundry room is located internally, that is, does not abut an external wall, a problem arises because one cannot vent a dryer through the adjacent wall to the outside environment. In such circumstances, dryer venting may occur vertically within a wall and vent through a roof to the outside environment.
BRIEF SUMMARY OF THE INVENTION
The purpose of this invention is to provide for easy installation of dryer venting which is particularly suitable for installation in laundry rooms that are internal to a structure. The following figures and descriptions describe how this may be done and illustrate the techniques and components which can be utilized for such installation. In one aspect of the invention the components for such venting may be assembled into a kit.
Although the best mode known to the inventor is set forth herein, it should be apparent that the invention is not limited to the particular embodiments shown.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described more particularly hereinafter with reference to the accompanying drawings, in which:
FIG. 1 is an exploded view of an in-wall unit in accordance with one aspect of the invention;
FIGS. 2A and 2B represent a top and side view of a cone shown in FIG. 1 .
FIGS. 3A , 3 B and 3 C are respective top, side and end views of an in-wall unit base shown in FIG. 1 .
FIGS. 4A , 4 B and 4 C are respective top, side and end views on an assembled in-wall unit.
FIGS. 5A , 5 B and 5 C are respective top, side and end views of mounting bracket shown in FIG. 1 .
FIG. 6 is an exploded view of a roof vent unit in accordance with one aspect of the invention.
FIG. 7 shows an assembled roof vent unit.
FIGS. 8A and 8B show respective top and side views of a roof vent body in accordance with one aspect of the invention.
FIG. 9 shows a roof vent flashing plate in accordance with one aspect of the invention.
FIG. 10 shows a roof vent exhaust plate in accordance with one aspect of the invention.
FIG. 11 shows a roof vent exhaust flap in accordance with one aspect of the invention.
FIG. 12 shows a roof vent top cover plate in accordance with one aspect of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Automatic clothes dryers typically contain a heating unit and a rotating drum which tumbles wet clothing in such a way as to expose it to heated air in order to facilitate drying. The heated air represents a particular fire hazard if it were to be vented into a room of the home or other building in which the dryer is located. Other equipment besides dryers may require venting to the external environment. Typically, at the back of an automatic dryer is an exhaust vent, typically a round exhaust pipe to which a flexible venting pipe from the dryer may connect to an external vent. Typically, in the prior art, such external vents were placed through holes in exterior walls to allow the heated air to vent to the external environment.
However, when a laundry room is to be located internal to a building structure in such a way as to not have access to an exterior wall, then other forms of venting must be utilized.
In accordance with the invention, venting of automatic dryers may occur through an interior wall to an external surface, such as a roof. The invention provides a particularly convenient and safe technique for the venting of dryers through an internal wall.
FIG. 1 of the drawing shows an exploded view of an in-wall unit in accordance with one aspect of the invention. A cone shaped unit 100 is attached to of an in-wall unit base 110 and serves to connect at its upper end to, for example, stove pipe which then forms an exhaust channel from the top of the cone shaped pipe to the roof or other external vent. The flared bottom end of the cone 100 received the flexible venting pipe from the dryer as described more hereinafter.
Studs in typical interior walls of a building tend to be formed by two by fours. However, in this case, since the venting diameter may be larger, two by six studs may be utilized for mounting the in-wall unit shown in FIG. 1 .
To mount the in-wall unit, in the embodiment shown, two mounting brackets 120 are mounted opposite each other on adjacent two by six studs, approximately thirty inches above the floor. The sides of the mounting brackets having two holes are aligned with a horizontal line previously drawn on the two by six stud using a level. The mounting brackets are then secured to the two by six stud using, preferably, two wood screws. The other mounting bracket is then attached in similar fashion so that the two mounting brackets 120 form a surface upon which the mounting plate 110 can rest. In one implementation, the side of the mounting bracket has a single hole is drilled out, preferably, to receive a number 12 self tapping screw so that the base plate 110 can be secured to the top of the mounting brackets 120 . Thus situated, the end wall unit is ready for connection to vent pipe, such as stovepipe, in the upper direction and for connection to the flexible pipe coming from the back of the equipment to the larger end.
FIGS. 2A and 2B represent a top and side view of the cone shown in FIG. 1 . The dimensions are given for an embodiment in which the base of the cone substantially matches the diameter if the hole in the base plate 110 . In this configuration, the cone is tack welded three times to the base unit 110 and the seam can be sealed with silicone rubber. Similarly, the seam formed along the rivet line shown in FIG. 2B for the cone element 100 can be sealed with silicone rubber seal.
Alternative ways for connecting the cone shaped element with the base plate will be discussed more hereinafter.
FIGS. 3A , 3 B and 3 C are respective top, side and end views of an in-wall unit base shown in FIG. 1 . The tabs extending down in FIG. 3B from the bottom of the in-wall unit base are used as follows. The flexible pipe from the dryer can be inserted through the hole in the base plate and forced to fit tight against the inside of cone 100 at the point of interference. The flexible pipe from the dryer is then held in place by metallized or metallic tape which connects the flexible pipe to the tabs shown in FIG. 3B , thus holding flexible pipe in position within the cone.
FIGS. 4A , 4 B and 4 C are respective top, side and end views of an assembled in-wall unit. This unit has not been mounted to the mounting brackets 120 . As noted above, the seam between the base plate and the bottom of the cone can be sealed with a silicone rubber seal and the tack welds, hold the conical sections securely in place.
FIGS. 5A , 5 B and 5 C are respective top, side and end views of the mounting brackets 120 . Although this figure gives preferred dimensions, the use of the mounting brackets has been described previously.
FIG. 6 is an exploded view of a roof vent unit in accordance with one aspect of the invention. The stovepipe connected to the in-wall unit may extend through the roof of the building or may turn 90-degrees and be routed to an exterior wall where it can be vented using prior art techniques. In the event that the stovepipe is to be vented through the roof, the roof vent unit shown in FIG. 6 and FIG. 7 provides preferred way of venting the dryer exhaust to the external environment. As shown in FIGS. 6 and 7 a roof vent body 600 , is firmly attached to a roof vent flashing plate 610 and to an exhaust plate 620 . An exhaust flap 630 has two tabs which extend beyond the outer extent of the body of the flap and are utilized to mount in recesses in the body 600 in such a way that the flap may open freely when air pressure from the exhaust vent is applied to its under surface. The exhaust flap 630 is held in place by a top cover plate 640 which can be removed in order to permit access to the stovepipe for clean out purposes.
FIG. 7 shows the assembled roof vent unit.
FIGS. 8A and 8B show respective top and side views of a roof vent body in accordance with one aspect of the invention. Note the two notches having a radius of 0.130-inches at the top of the body adjacent the bend line.
FIG. 9 shows a roof vent flashing plate in accordance with one aspect of the invention. The flashing plate forms the base of the roof vent unit. The body 600 is attached to the flashing plate, preferably by soldering in a continuous seam around the contact points between the bottom of the body 600 and the flashing plates 610 . The alignment of the radius of the hole in the flashing plate and the radius of the curved portion of the body substantially coincide.
FIG. 10 shows a roof vent exhaust plate in accordance with one aspect of the invention. The roof vent flashing plate 620 attaches just behind the 0.130 radius notches found in the body 600 . It is mounted to permit the tabs on the exhaust flap 630 to rest in the notches without interference. The exhaust plate is tack soldered along a slope up from the flashing plate and continuously soldered along the bottom connection to the flashing plate.
FIG. 11 shows a roof vent exhaust flap in accordance with one aspect of the invention. The 0.125 inch tabs at the top of the exhaust flap are placed in the 0.130-inch diameter notches in the top of the roof vent body 600 . They sit there freely in such a way as to allow the roof vent flap to open when air from the exhaust of the dryer is applied against its surface. The roof vent exhaust flap 630 is held in place by attaching the top cover plate 640 to the body.
FIG. 12 shows a roof vent top cover plate in accordance with one aspect of the invention. The roof vent cover plate is designed to be removable to permit the exhaust path to be cleaned out for servicing. The top cover plate is removed, the exhaust flap is removed and the openings are such that a flue brush can be inserted down into the stovepipe to permit cleanout of the exhaust pathway.
Some alternative configurations exist. First, in less durable installations, the in-wall unit base plate may be secured with tape to the mounting brackets 120 , rather than using the self-tapping screw. Further, in another embodiment, the conical section can be built with a larger diameter so that it extends only partially through the opening in the in-wall base plate 110 . It can then be held in place using tape and the tabs on the base plate 110 . In this arrangement, it may be desirable to have additional tabs at the large end of the conical section 100 to permit the taping of the flexible pipe coming from the dryer unit.
The shortest straightest route is best when routing stove pipe to the desired termination point. In some jurisdictions, code requires a maximum of 25 feet from dryer determination point. Each 90-degree tern may subtract 5 feet and each 45-degree turn may subtract 2½ feet. Once the in-wall unit is installed, the wall can be finished with drywall and paint.
The invention described herein is not limited to the specific examples shown, but rather has a broad applicability to communications generally. | Venting through the walls of an interior room of a building to an external environment is facilitated by apparatus and techniques for mounting an in-wall unit for interfacing with the exhaust ports of equipment, such as dryers, using flexible pipe. The in-wall unit connects with venting pipe, such as stovepipe, for connecting to the external environment through an exterior surface, such as a roof. If a roof exhaust is desired, a vent assembly is provided that contains a flap that automatically closes when the exhaust flow terminates, but opens when venting is underway. The flap is removable so that cleanout of path between the in-wall unit and the room exhaust can easily occur. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a pathlength controller for a ring laser gyroscope and, more particularly, to an improved pathlength control assembly having certain thermally expansive components to allow the controller to achieve a relatively wide range of axial displacement to provide the greater range of dynamic mirror movement needed for a multioscillator ring laser gyroscope.
2. Description of Related Art
Ring laser gyroscopes are an alternative form of rotation sensors which do not require the use of a spinning mass characteristic of a mechanical gyroscope. A ring laser gyroscope employs a Sagnac effect to detect rotation optically, as an alternative to the inertial principles upon which a mechanical gyroscope operates. Planar ring laser gyroscopes, of both triangular and square geometries, have been used in inertial navigation systems and flight control systems regularly in both commercial and military aircraft. The primary advantage of the ring laser gyroscope over the spinning wheel mechanical gyroscope is its ability to withstand relatively large mechanical shock without permanent degradation of its performance. Because of this and other features the expected mean time between failures of most RLG inertial navigation systems are several times longer than the mechanical gyroscopes they replace. The planar ring laser gyroscope was a first attempt at a non-mechanical truly strap-down inertial navigation system.
The earliest developed ring laser gyroscopes have two independent counter-rotating light beams or other electromagnetic propagation which travel within an optical ring cavity. In an ideal model of the ring laser gyroscope, these two light beams propagate in a closed loop with transit times that differ in direct proportion to the rotation rate of the loop about an axis perpendicular to the plane of the loop. However, when one steps away from the ideal model of two mode ring laser gyroscope operation, various sources of inaccuracy are observed. Among these inaccuracies in rotational sensing of a two-mode planar ring laser gyroscope is the phenomenon known as frequency lock or mode locking. Reflections and backscatter from the intra-cavity element and instabilities of the magnetic field associated therewith cause difficulties such as mode locking that need to be overcome in order to build a fully optical navigational grade multioscillator ring laser gyroscope. Mode locking is a major difficulty at low rotation rates where the ring laser gyroscope produces a false indication that the device is not rotating. If the rotation rate of a ring laser gyroscope starts at a value above that of where lock-in occurs, and is then decreased, the frequency difference between the beams disappears at a certain input rotation. This input rotation rate is called the lock-in threshold. The range of rotation rates over which lock-in occurs is generally called the dead band of the ring laser gyroscope. Lock-in arises from the coupling of light between the beams. One means of overcoming the lock-in effect of the counter-propagating modes of light within a two mode gyroscope is to mechanically dither the mirrors or body of the gyroscope. This technique is known as rate biasing or mechanical dithering and prevents counter propagating waves from locking at low rotation rates. A more detailed explanation of the problems associated with a planar two mode gyroscope are described in Laser Applications, edited by Monte Ross, pages 133-200 (Academic Press, 1971).
Even the most effective mechanically dithered ring laser gyroscope adds a noise component to the output of the ring laser which in turn reduces its ultimate accuracy. Also, the presence of mechanical dither, either is mirror or full bodied dither, detracts from the desired goal of a fully strapped down inertial navigational unit. Since one of the primary benefits of a ring laser gyroscope is that it overcame the need for mechanical or moving parts, a body dithered planar two mode gyroscope does not truly meet this goal. In an effort to achieve a fully optical ring laser gyroscope, the non-planar multi-mode ring laser gyroscope was developed to overcome the effects of mode locking without the need to dither. The term (multioscillator) refers to four modes of electromagnetic energy that propagates simultaneously in the cavity as opposed to the usual pair counter-propagating linearly polarized modes that exist in the conventional two mode gyroscope. A detailed discussion of the operation of the multi-oscillator laser gyroscope is presented in the article entitled "Multioscillator Laser Gyros" by Weng W. Chow, et. al., at pages 918-936, IEEE Journal of Quantum Electronics, Vol. QE-16, No. 9, September 1980. An example of this theory of multioscillator ring laser gyroscope may also be found in U.S. Pat. No. 4,818,087 entitled "ORTHOHEDRAL RING LASER GYRO" issued Apr. 4, 1989 to Raytheon Corporation (Terry A. Dorschner, inventor); and U.S. Pat. No. 4,813,774 entitled "SKEWED RHOMBUS RING LASER GYRO" issued Mar. 21, 1989 to Raytheon Corporation (Terry A. Dorschner, et. al., inventor).
With reference to FIGS. 1A and 1B, the basic multi-oscillator ring laser gyroscope has an optical path 10 formed between four mirrors 12, 14, 16 and 18. Mirrors 16 and 18 are generally fixed, and one of these mirrors may be semi-transparent in order to allow light to leave the resonator and fall upon photodetectors (not shown and external to the path) for signal processing in order measure rotation of the gyroscope. When the signals are subtracted during the electronic processing to remove the Faraday bias, the scale factor of the gyroscope is doubled over the conventional ring laser gyroscope. At least one of the other mirrors 12 and 14 are transducer driven mirror assemblies which are used to effectuate pathlength control. A Faraday element 15 is also present in the optical path 10 in order to effectuate non reciprocal splitting of pairs of left circularly polarized (LCP) and right circularly polarized (RCP) light beams. The multioscillator ring laser gyroscope contains the two gyroscopes (GYRO 1 and GYRO 2 of FIG. 1B) symbolized by their respective gain lines 22, 24, 26, and 28 under the atomic spectra resonant gain profile 20. Reciprocal splitting between left circularly polarized (LCP) and right circularly polarized (RCP) light beams is accomplished by the non-planar geometric configuration of the mirrors 12, 14, 16, and 18, shown in an exaggerated form in FIG. 1A as a quadrilateral optical path split (the broken line connecting mirrors 14 and 16). The multioscillator ring laser gyroscope uses the Faraday element 15 within the cavity (or, alternatively, a magnetic field on the gain plasma) to provide a phase shift between the counter propagating waves to prevent mode locking. With reference to FIG. 1B, the non-planar ray path reciprocally rotates the polarizations of the counterpropagating light beams by many degrees yielding the necessary high purity circular polarization. This splitting is known as reciprocal splitting and typically is in the range of 100 MHz. By placing a Faraday element 15 in the beam path of a nonplanar ring laser gyroscope, and when the proper magnetic field is applied to the Faraday glass element, nonreciprocal splitting of each gyroscope is achieved. At least four modes are produced: a left circularly polarized anti-clockwise frequency 22 (L a ), a left circularly polarized clockwise beam 24 (L c ), a right circularly polarized clockwise beam 26 (R c ), and a right circularly polarized anticlockwise beam 28 (R a ). The Faraday splitting between clockwise and anti-clockwise modes is about 1 MHz.
Although a multioscillator ring laser gyroscope provides a strap-down method of providing rotation measurement which is not subject to low rotation rate mode locking and therefore needs no dither mechanism, all ring laser gyroscopes are prone to optical pathlength changes due to thermal expansion of the gyroscope frame. Therefore, the optical pathlength of the gyroscope must be controlled and monitored to make certain that the resonant cavity operates at the same gain line of the atomic spectra gain curve. Due to the multiplicity of their applications, ring laser gyroscopes are required to operate over a wide temperature range, such as -55° C. to +70° C. Since the laser light beam emitted by the active gain region of the gyroscope propagates around the ring laser by means of reflection off the surfaces of at least 3 mirrors, thermal expansion of the frame and mirrors will cause a significant change in cavity resonant wavelength. It is therefore necessary to provide a pathlength control mechanism to slightly vary the optical pathlength of the gyroscope ring resonator in order to preserve the fundamental resonance of the cavity to which all sensing instrument components of the gyroscope are calibrated. Even where low expansion glass materials are used for building a monolithic frame which supports to optical cavity path between the mirrors, the pathlength of a ring laser gyroscope will still experience a substantial change in path length during temperature changes. This change can be as much as 5 wavelength or more at the resonant frequency of the light produced by the gaseous active medium, such as a helium-neon mix. In an active path length control system, the changes in pathlength due to thermal expansions and contractions are monitored by detector electronics and provide feedback information for driving one or more piezo-electric transducers. However, the standard active pathlength control assembly does not provide sufficient axial movement of the mirror surface over a sufficient range to accommodate the dynamic changes due to temperature found in a multioscillator ring laser gyroscope.
The applicants are aware of certain disclosures by Raytheon Corporation of Lexington, Mass. directed to a Passive Pathlength Control for Ring Laser Gyroscopes and a High Performance Hybrid Pathlength Control, as well as Laser Pathlength Tuning Elements, which are the subject of a United States Patent Application entitled Passive Pathlength Control Mirrer For Laser filed Dec. 18, 1990, as Ser. No. 07/630,213. The assignee of this application is a Licensee of these disclosures from Raytheon Corporation. These disclosures (which were written before the conception of the present invention by the applicants herein) are directed to a passive pathlength control assembly which performs pathlength control solely by making use of thermally expansive materials to achieve such control. The Hybrid Pathlength Control disclosure suggests the use of at least one such passive controller and at least one other piezo-electric active controller for the same optical path of a multioscillator ring laser gyroscope instrument.
SUMMARY OF THE INVENTION
What is needed is a pathlength control assembly for a ring laser gyroscope that is effective over the entire dynamic range of change in the pathlength of a multioscillator ring laser gyroscope. Disclosed herein is an improved pathlength control assembly for use in a multioscillator ring laser gyroscope, which may comprise a mirror, a mirror mount for mounting the mirror on an axially deflectable membrane, and a mirror post coupled to the deflectable membrane. The improved pathlength control assembly also has at least one transducer and a supporting plate for supporting the transducer. A thermally expansive driver post for axially driving the mirror post is used in conjunction with the transducer, which transducer is bonded onto the supporting plate. In this manner, the active transducer may move the plate for axially deflecting in response to an electronic input signal. The thermally expansive driver post passively displaces the mirror post, the membrane, and the mirror, while the transducer actively displaces the driver post and mirror post. In this manner, the combined action of the active transducer driven controller and the thermally expansive driver post provides both passive and active mirror displacement functions in order to achieve the full axially driving range needed to drive said mirror post and mirror over a relatively wide range needed to properly operate a multioscillator ring laser gyroscope. The passive thermally expansive driver post is preferably comprised of a material having a relatively high coefficient of thermal expansion. This material may be selected from the group of materials consisting of BK7 Glass, FK 5 Glass, FK 52 Glass and Aluminum. Low expansion materials such as Cervit, Zerodur, and ULE glass may be used to make the mirror mount and the transducer supporting plate.
The thermally expansive driver post, through thermal expansion, provides compensation to the thermal expansion effects upon the Faraday element; since, the driver post expands with an effect opposite to that of the thermal expansion of the Faraday element.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a prior art drawing showing a schematic view of a multioscillator ring laser gyroscope instrument illustrating the operation of the cavity length control system of this invention.
FIG. 1B is a PRIOR ART graphic representation illustrating the atomic gain medium curve of the multioscillator ring laser gyroscope of FIG. 1A operating at the resonant frequencies of a gaseous medium ring laser gyroscope.
FIG. 2A is a cross-sectional view of a preferred embodiment of the pathlength control assembly for a multioscillator ring laser gyroscope of this invention.
FIG. 2B is a perspective isometric view of a preferred embodiment of the pathlength control assembly for a multioscillator ring laser gyroscope of this invention.
FIG. 2C is an exploded isometric view of the pathlength control assembly of FIG. 2B.
FIG. 3A is a cross-sectional view of an alternative embodiment of the pathlength control assembly for a multioscillator ring laser gyroscope of this invention.
FIG. 3B is a perspective isometric view of the alternative embodiment of the pathlength control assembly of FIG. 3A for a multioscillator ring laser gyroscope of this invention.
FIG. 3C is an exploded isometric view of the pathlength control assembly of FIG. 3B.
FIG. 4A is a cross-sectional view of an another alternative embodiment of the pathlength control assembly for a multioscillator ring laser gyroscope of this invention.
FIG. 4B is a perspective isometric view of the alternative embodiment of the pathlength control assembly of FIG. 4A for a multioscillator ring laser gyroscope of this invention.
FIG. 4C is an exploded isometric view of the pathlength control assembly of FIG. 4B.
FIG. 5A is a cross-sectional view of yet another alternative embodiment of the pathlength control assembly for a multioscillator ring laser gyroscope of this invention.
FIG. 5B is a perspective isometric view of the alternative embodiment of the pathlength control assembly of FIG. 5A for a multioscillator ring laser gyroscope of this invention.
FIG. 5C is an exploded isometric view of the pathlength control assembly of FIG. 5B.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIGS. 2A through 2C, there is disclosed a preferred embodiment of the Pathlength Control Assembly for Ring Laser Gyroscopes of this invention. It can be seen that the basic components of the path length controller mirror assembly 30 include a membrane-type mirror housing 38 and a backing plate 32, which serves to support the mirror housing 38 and is sandwiched between the mirror housing 38 and the driver body 50. The housing 38, supports the mirror 44, which is mounted on the diaphragm membrane 46. This mirror 44 is positioned facing into the gyroscope frame body 40 for reflecting light along the light beam path 67 off of the mirror's surface. The housing 38 has an outer cylinder 34 and a central mirror post 36. The annular surface of the mirror post 36 and the outer annular surface of the outer cylinder 34 are flush against the circular backing plate 32.
The driver body 50 includes a driver post 54, which during activation of the cavity length control assembly causes the driver post 54 and forward surface 56 to move axially along the direction shown at 42 (FIG. 2B). Such axial movement of the driver post 54 causes axial movement by the mirror post 36 against the flexible mirror membrane 46, thereby allowing axial movement of the mirror 44 between a rest position and a flexural position 44' (shown in phantom). FIG. 2C additionally shows that the driver body 50 has an outer surface which is flush against the backside of the backing plate 32.
Positioned on either side of a driver plate 61, at the back end of the driver body 50, are two piezo-electric elements 60 and 62. The piezo-electric element 62 has an inner annulus to accommodate placement of the driver post 54 of the driver body 50. The piezo-electric elements 60 and 62 are secured and bonded to the front and back surfaces, respectively, of the driver plate 61 by the use of epoxy cement. These elements are often bimetallic or bimorphic, such that when they are alternatively polarized by applying a voltage thereto from electrical terminals 64 and 66 along electrical wiring 63A and 63B (which may be passed through the air vent hole 65), the driver body 50 and driver post 54 move axially along the central axis of the driver body 50, back and forth as needed in the axial direction 42. Such movement results in positioning the backing plate 32 to a new position 69, and moving the mirror membrane 46 of the mirror housing 38 to a new position 68, all of which results in the desired axial movement 42 of the mirror surface 44 out to 44'.
Preferably (except for the piezo-elements 60 and 62 and the driver post 54), all the components which make up the assembly 30 (like the mirror housing 38, the backing plate 32, and the driver body 50) should be made from the same material to decrease the effects of thermal expansion. Materials of relatively low thermal expansion coefficients such as Cervit, Zerodur, ULE (Ultra Low Expansion) Glass are among the most desirable to use to manufacture the pathlength control assembly 70. In this manner, the assembly 70 is able to operate over a wide temperature range from -55° C. through at least +70° C. Due to the wider range needed to properly operate a multioscillator ring laser gyroscope, the driver post 54 in the preferred embodiment is made from materials showing a relatively higher thermal expansion coefficient, including BK7 Glass, FK 5 Glass, FK 52 Glass, and Aluminum. In this manner, the driver post 54 can operate as a passive pathlength control element which extends the range of the active piezo-electric element operation.
In operation, an electrical stimulus is provided as shown along the electrical wiring 63A and 63B. One will note that the piezo-elements 60 and 62 are charged so that upon application of voltage, one element expands and the other element contracts to bow in an axial direction along the central axis 42 of the pathlength control assembly 30. The piezo-elements 60 and 62, acting with the driver plate 61 and compensating element, mirror post 54, then cause the driver plate to bow and move the central mirror post 36 in an axial direction 42. A vent hole 65 (FIG. 2A) is provided to allow pressure equalization within the pathlength control assembly 30 and to also allow passage of the wiring 63A and 63B from the piezo-elements 60 and 62 from the inside of the driver body 50 to the outer surface for electrical connection at the electrical power supply terminals 64 and 66 outside the assembly 30.
Movement of the central mirror post 36 of the mirror housing 38 causes the reflective mirror surface 44 to move back and forth along the central axis of the mirror assembly 30, thereby allowing active cavity or optical pathlength control to be accomplished. It shall be understood that the driver post 54 is needed to accomplish the desired axial translation, and that such translation requires a pathlength control assembly 30 of hybrid design.
An effective technique to test the hybrid pathlength control mirror assembly of this invention is to perform a "mode scan". A mode scan requires the application of no electrical voltage to the pathlength control piezo-electric elements 60 and 62, while simultaneously monitoring over a temperature range the outputs of the light intensity emitted from the ring laser gyroscope through a semi-transparent corner mirror. Under such a test, the pathlength control mirrors move through a minimum number of modes. The dynamic range over temperature of the hybrid design is increased by using the driver post 54 as a compensating element.
By combining both passive and active pathlength control in the pathlength controller mirror assembly 30 of this application, one shows an inherent simplicity in such pathlength control assembly configurations in comparison with previous designs.
With reference to FIGS. 3A through 3C, the mirror housing 74 include a forward surface which supports the mirror surface 84 and acts as a membrane surface 82. The membrane surface 82 also acts as a mirror substrate for the mirror surface 84. The mirror housing 74 has an outer cylinder 86 which provide symmetry and balance to the path length control assembly 70.
It can be seen that the basic components of the pathlength control assembly 70 include a mirror housing 74 and a backing plate and driver 76, which serves in the dual capacity as a supporting plate and driver and which is sandwiched between the piezo-electric elements 78 and 80. The piezo-electric element 78 has an inner annulus to accommodate placement of the driver post 75 of the mirror housing 74. The piezo-electric elements 78 and 80 are secured and bonded to the front and back surfaces, respectively, of the backing and driver plate 76 by the use of epoxy cement.
The mirror housing 74 is affixed to a forward mirror and diaphragm supporting plate 72 which supports the mirror surface 84 and acts as a membrane surface 82. The membrane surface 82 also acts as a mirror substrate for the mirror surface 84. The mirror housing 74 has an outer cylinder 86 which provide symmetry and balance to the path length control assembly 70.
As in the preferred embodiment of FIGS. 2A through 2C, the driver post 75 may be made from a relatively higher thermal expansion coefficient material to allow the driver post 75 to compensate for thermal expansion and provide a passive cavity length sub-component to the pathlength controller assembly 70.
In operation, an electrical stimulus is provided as shown along the electrical wiring 88A and 88B. One will note that the piezo-elements 78 and 80 are charged so that upon application of voltage, one element expands and the other element contracts to bow in an axial direction along the central axis 87 of the pathlength control assembly 70. The piezo-elements then cause the backing plate to bow and move the mirror post 75 in an axial direction. A vent hole 90 is provided to allow pressure equalization within the pathlength control assembly 70 and to also allow passage of the wiring 88A and 88B from the piezo-elements 78 and 80 from the inside of the housing 74 to the outer surface for electrical connection with the electrical power supply terminals 91 and 93 outside the assembly 70. It should be noted that only a single vent hole through the mirror housing 74 is needed to accomplish the pressure equalization required, (when the mirror membrane 82 moves in and out along the axial direction of the assembly 70).
Movement of the forward surface 95 of the mirror post 75 of the mirror housing 74 causes the reflective mirror surface 84 to move back and forth along the central axis of the mirror assembly 70, thereby allowing active cavity or optical pathlength control to be accomplished. It shall be understood that heretofore an additional driver body 50 (of FIG. 3 of U.S. Pat. No. 4,824,253) was needed to accomplish the desired axial translation that the invention of this application accomplishes by using the backing plate 76 in a dual capacity such as a driver and piezo-element support plate. Such design allows a considerable cost savings due to the elimination of the driver body 50 component.
A particularly deleterious error source in the performance of any pathlength controller assembly is the mirror tilt, i.e., the mirror motion in directions other than its perpendicular axis. As it was heretofore taught in the art (i.e. U.S. Pat. No. 4,861,161 to Ljung), such mirror tilt can cause bias shifts in the ring laser gyroscope output under changing temperature.
An effective technique to test the pathlength control mirror assembly for mirror tilt is to perform a "mode scan". A mode scan comprises the application of full electrical voltage to the pathlength control piezo-electric elements 78 and 80, while simultaneously monitoring of the outputs of light intensity detectors placed adjacent one of the output mirrors of the ring laser gyroscope. Under such a test, the pathlength control mirrors move through their maximum number of design modes, and a trace of the output signals from the photo detectors show a curves like the one depicted in FIG. 1B (the gain profile). Any changes in the maxima of the successive gain profiles under a mode scan would be indicative of mirror tilt.
Pathlength control assembly and mirror using a dual function backing and driver plated 76 have been tested for mirror tilt errors (for two mode gyroscopes) according the mode scan method as described heretofore. In a manner distinct from the teachings of the prior art (including U.S. Pat. No. 4,861,161), the pathlength control assembly of this application shows an inherent simplicity in comparison with previous designs. This simplicity of design allowed the applicant's invention to test quite successfully with regard to mirror tilt. If one were to build and test a number of pathlength control assemblies according to the teachings of FIGS. 3A and 3C, such assemblies, after integration into a ring laser gyroscope, would undergo a variety of gyroscope performance tests, including the mode scan test for pathlength controller mirror tilt. Such test results would show that over a scan of several modes there was no measurable change in the maxima of the gain profiles traced during the mode scan.
With reference to FIGS. 4A through 4C, there is shown a pathlength control assembly 100 which is a close alternative to the embodiment shown in FIGS. 3A through 3C. The pathlength control assembly 100 is comprised of a mirror housing 102, which housing 102 includes a mirror membrane 104 supporting a mirror surface 106. Like the embodiment disclosed in FIGS. 3A through 3C, there is no separate driver body; rather, a separate driver 110, working together with its driver post 112, serves the dual function of driver and supporter for the piezo-electric elements 114 and 116. Like the previously described embodiments, the piezo-electric elements 114 and 116 provide forward axial motion to the driver 110, its driver post support plate 108, and the driver post 112. The piezo-elements are energized by an external electrical power supply through terminals 117 and 119 along electrical wiring 111A and 111B, which may be threaded through the vent hole 115. When energized, the forward surface 113 of the driver post 112 is pressed against the mirror post pedestal 118, causing the mirror membrane 104 to move, carrying forward the mirror surface 106 and thereby performing cavity length control of the ring laser gyroscope. The embodiment of the invention shown in FIGS. 4A through 4C may be distinguished from the embodiment of FIGS. 3A through 3C, in that rather than having a single driver post 75 that is affixed to the backing plate 76 and the mirror supporting plate 72, the mirror housing 102 is integral with the mirror post pedestal and forms a single housing made from a material of low coefficient of thermal expansion. Also, the driver 110 is a single unitary component made from a high thermal coefficient of expansion material and comprises the driver post support plate 108 and the driver post 112. Thus, a more rigid structure is provided, and, both the driver post 112 and the support plate 108 are formed from high thermal expansion material.
With reference to FIGS. 5A through 5c, a path length control assembly 120 is shown generally and comprises a mirror housing 126, a driver 130, and a backing plate and driver 136. The mirror housing includes a flexible mirror membrane 124 and mirror surface 122, as well as a tapered mirror post 128 integral with the forward surface of the housing 126. The driver 120 is comprised of a driver expansion plug 132, which is movably telescoped within the driver barrel chamber 134. The backing plate and driver 136 support the piezo-electric elements 138 and 140 which are driven by an external power supply from terminals 141 and 143 along wires 144A and 144B threaded through the vent hole 142.
In operation, as the piezo-elements 138 and 140 are activated, the backing plate and driver 136 tends to bow forward driving the compensating element, the driver expansion plug 132, axially forward against the tapered mirror post 128. Also stabilization is maintained at the interface of the forward surface 135 of the driver 130 as it is pressed against the outer cylindrical surface of the mirror housing 126. The driver expansion plug 132 also provides passive cavity length control, since it may be made from a high coefficient of expansion material such as aluminum or BK 7 Glass. The tapered mirror post 128 provides a distributed and uniform axial force to the mirror surface 122 as the mirror membrane 124 is flexed. The design of the embodiment of FIGS. 5A through 5C provides additional stability and prevents mirror tilt that otherwise might be associated, in the past, with cavity or pathlength control assemblies.
While preferred embodiments are shown, it is clear that alternative equivalent embodiments of the invention may be envisioned which provide adequate alternatives, performing similar functions to the preferred embodiment, yet using the basic teachings and principles of the herein described invention. For example, any material exhibiting a high coefficient of thermal expansion would be useful to act as the compensating element of the hybrid pathlength controller of this invention. Also, while the pathlength control assembly of the disclosed invention may be preferably used in a multioscillator ring laser gyroscope, it is also useful for any ring laser gyroscope, any ring laser, or to stabilize a linear laser. Thus, alternate embodiments having substantially equivalent functions or structures are intended to be comprehended within the scope of the appended claims. | Disclosed herein is a Pathlength Control Assembly for Ring Laser Gyroscope comprising, in a preferred embodiment, a mirror, coupled to a mirror housing including a mirror post, wherein the mirror is mounted on an axially deflectable membrane of the housing. A pair of piezoelectric transducers are responsive to an electronic input signal and mounted to a backing plate. The transducers are mounted within a driver housing and drive a driver post which is made from a thermally expansive material. As the backing plate is deformed to drive the mirror post to axially deflect the mirror membrane, the central driver post passively expands in response to temperature changes. In this manner, the transducers and thermally expansive mirror post act in conjunction to both actively and passively drive the mirror post over the full dynamic range of multioscillator or other ring laser gyroscope. | 6 |
FIELD OF THE INVENTION
[0001] The invention relates to a method and system for sensing turbine and compressor blades in a turbine engine.
BACKGROUND TO THE INVENTION
[0002] Eddy current sensors are often used within turbine engines to detect rotating turbine and compressor blades. Typically, signals from the sensor are used to generate a timing signal. This timing signal is then used to accurately measure the position of each blade relative to the other blades in the turbine engine and the turbine shaft in near real time. From these timing signals, various measurements, such as blade position, flutter, vibration, untwist, etc may be derived.
[0003] Eddy current sensors detect the presence of conductive materials within their sensing field of view. Many variables affect the quality of the measurements obtained from eddy current sensors. For example, the sensor output scaling is nonlinear and changes with varying target displacement. This means that there may be a great variation in signal level between individual blades, due to their varying tip heights. This is especially true at small displacements because of the nonlinear characteristics of the signal with respect to displacement. The signal amplitude increases roughly exponentially as displacement is reduced.
[0004] Because of the blade tip height variation, it is therefore necessary to treat each blade signal separately when processing it to find a repeatable timing point. This is usually done by finding some form of derived midlevel or zero crossing point in the signal arising from each blade. However, the change in an eddy current sensor output due to the presence of a sensed target is generally unipolar in nature, and so is not zero referenced. Accordingly, determination of a midpoint in a signal for use as a blade timing reference is relatively complex. This complexity means that the associated signal processing electronics is both complex and power hungry.
[0005] There are a number of methods that have been developed in order to determine a fixed reference point in signals of this type from eddy current sensors. One method currently used, involves separately determining the positive and negative waveform peaks, either in electronic hardware or software, and then dividing the sum of these values by two to obtain the midpoint reference. The drawback of this method is that it requires either a very fast and consequently power hungry, analogue to digital converter and software processor, or fast peak detectors using capacitive storage methods. Peak detectors are also very power hungry and wasteful, owing to the necessity to fast charge and then fast reset the charge-hold capacitors at each blade passing.
[0006] It is also possible, using hardware and/or software, to measure the angular rate of change in the waveforms using differentiation or signal averaging. As stated, generally the complexity and processing speed required increases the power requirements of the associated electronics significantly. Both methods also generally add delays in the processing due to the need to use data over an extended window of time. This typically requires a look ahead buffer or other measurement phase shift, to provide a “walking-window” of data, with calculations centred on the middle of the window.
[0007] It is an object of the invention to provide a less complex means of extracting timing signals from an inductive sensor for measuring the passage of blades in a turbine engine that has reduced power requirements when compared to prior systems, and reduced sensitivity to environmental factors and build tolerances.
SUMMARY OF THE INVENTION
[0008] The present invention is defined in the appended independent claims, to which reference should be made. Preferred features are set out in the dependent claims.
[0009] The present invention uses a pair of coils arranged parallel to the path of the blades, such that in use each blade passes the first coil and then subsequently passes the second coil. The use of a pair of sensing coils provides for inherent accuracy. The amplitude of signals generated in the coils does not significantly affect the determination of the timing signals, because the timing signals are derived from a comparison of the signals from each coil. Only noise and gross amplitude variations need to be catered for. Because of this, the electronic hardware and/or processor and software complexity requirements are reduced, and the associated power requirements are reduced, compared to the prior art. Furthermore, the system and method of the present invention results in improved noise rejection, reduced sensitivity to build tolerances, reduced sensitivity to temperature variation effects and reduced sensitivity to amplitude variation effects.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Examples of the present invention will now be described in details with reference to the accompanying drawings, in which:
[0011] FIG. 1 is a schematic diagram illustrating a sensor in accordance with the present invention;
[0012] FIG. 2 a illustrates typical signals from both sensor coils;
[0013] FIG. 2 b shows the signals of FIG. 2 a after half wave amplitude modulation envelope detection, amplification and filtering, and are overlaid to show their phase relationship;
[0014] FIG. 3 a is a side view of the coil arrangement in a sensor in accordance with the present invention;
[0015] FIG. 3 b is an end view of FIG. 2 a;
[0016] FIG. 4 shows a sensor processing configuration for use in a sensor in accordance with the present invention; and
[0017] FIG. 5 shows timing signals generated by the processing configuration illustrated in FIG. 4 .
DETAILED DESCRIPTION
[0018] FIG. 1 is a schematic diagram illustrating a sensor in accordance with the invention. The sensor comprises two sensor coils 10 , 11 arranged side by side parallel to the path of blades 12 , fixed to a rotating shaft in a turbine engine. The blades each pass close to the first sensor coil 10 and subsequently pass the second sensor coil 11 . Both coils are driven by a fixed frequency oscillator 14 so that an oscillating current passes through each coil.
[0019] Each sensor coil therefore produces an oscillating magnetic field through which the tip of each blade passes as it rotates. The oscillating magnetic fields set up eddy currents in the blade tips (which are formed of electrically conductive material). The eddy currents generate their own magnetic field which modify the impedance and inductance of the sensor coils, and hence the current in the sensor coils.
[0020] The modification of the current signal in the sensor coils occurs with each passing of a blade tip and so is essentially a periodic modulation of the oscillator signal. The two coils give rise to similar modulation but with a phase difference between them, owing to the time delay between the passing of a blade 12 past the first sensor coil 10 and the passing of that blade past the second sensor coil 11 .
[0021] FIG. 2 a illustrates the signals obtained at the outputs 18 and 19 . The signal at the first output 18 is shown at the top, and is an amplitude modulated version of the signal from the oscillator 14 . The signal at the second out put 19 is shown below, and is similar to the signal at the first output 18 , but with a phase shift in the modulating envelope.
[0022] FIG. 2 b shows the signals from the first and second outputs 18 , 19 , after half-wave amplitude modulation envelope detection, amplification and filtering, and are overlaid to show their phase relationship. A timing signal can be generated from the points at which the amplitudes of the two demodulated signal are equal.
[0023] In FIG. 1 , the sensor coils 10 , 11 are arranged in bridge formation with two resistors 16 , 17 of the same value. The bridge circuit is driven from a fixed frequency oscillator 14 via the junction of the two resistors, with respect to the junction of the two coils 10 , 11 . The symmetrical nature of the bridge configuration provides advantages. With a single oscillator, any remnant excitation carrier present in the two processed signals is synchronous and approximately equal. This means that any carrier noise present in the signals presented to a comparator comparing the two signals effectively cancels out, reducing timing jitter.
[0024] The excitation oscillator type is unimportant, but preferably produces a stable amplitude sine wave of suitable frequency with low phase and harmonic distortion (allowable levels of distortion would depend on final timing accuracy required).
[0025] The excitation frequency required and the characteristics of the inductors and resistors utilised will be dependent on the frequency and bandwidth requirements for the sensor design.
[0026] The characteristics of the two coils 10 , 11 do not need to be especially matched. Any drifts in their characteristics would be in the same direction, so would essentially cancel each other out during a comparison of the two sensor coil signals.
[0027] The characteristics of the two resistors 16 , 17 used for the sensor bridge are also not of great importance as long as their temperature and ageing drifts are similar in direction and magnitude. However, even relatively high accuracy parts have become low cost in recent times. Standard 1% 100 ppm/° C. or 50 ppm/° C. thick film or thin film parts would be more than accurate and stable enough.
[0028] The two resistors 16 , 17 in the sensor bridge should ideally be of equal value and chosen to roughly match the inductor impedances at the nominal drive frequency used. If desired, one of the resistors could be small outline transistor (SOT) or a potentiometer trimmer, providing a means to obtain a fine signal balance. This would further reduce the effects of any coil or resistor mismatch in the bridge at build time.
[0029] The excitation oscillator amplitude should be large in order to obtain a high signal to noise ratio and large modulation amplitude but, at the same time, small enough to avoid approaching saturation of the inductors or clipping in the subsequent electronic processing. In this example, two amplitude modulation (AM) envelope detectors are used to demodulate the target signals from the carriers, so the peak carrier amplitudes at each coil must be greater than the demodulator diode forward voltages plus the amplitude of any modulation. Allowance for diode forward voltage changes with temperature must also be included, to ensure enough headroom is available under all conditions.
[0030] Following demodulation, the two signals are amplified and further filtering is applied if desired. The signals are then presented to the inputs of an analogue comparator, to generate timing edges at the point at which the modulation waveforms from the two coils cross over, as described in greater detail with reference to FIGS. 4 and 5 .
[0031] The distance between the centres of the two sensor coils may need to be varied slightly from application to application, and should be chosen to suit the target blade thickness. For best accuracy the coil-coil distance should be chosen to cause the modulation signals cross near their 50% amplitude point. This is where the signal amplitudes are likely to be changing most steeply, so generating timing signals at those points will minimise the effects of any amplitude jitter/noise at the signal comparator inputs. Alignment at higher or lower levels is possible, but noise effects significantly increase as the trigger point approaches the top or bottom of the waveforms, where the rate of voltage change shallows.
[0032] Because the coils are of closely similar build, mounted in close proximity, driven by the same excitation signal and sensing the same target, any drifts or changes in their physical and electrical characteristics will also be similar. This will also largely hold true for external influences. Any noise pick-up in the coils will be effectively minimised by common-mode cancellation when the two signals are compared in the later processing.
[0033] FIGS. 3 a and 3 b show a possible configuration of the sensor coils 10 , 11 . The two sensor coils 10 , 11 may be round, ‘D’ shaped or rectangular as required to optimise the signal characteristics for the blade width, sensor spacing etc. and various shapes are shown in dashed lines. The overall shape of the housing 30 is largely application dependent and not critical to the principle of operation. The housing 30 supports the coils in a stable, fixed position and holds the coils at the same height and parallel with one another. The distance of the coils from the blade tip is chosen for a particular application.
[0034] The sensor is typically positioned in a turbine casing such that the junction between the two coils aligns approximately with the blades' tip angle, i.e. aligned with the tangent of the blade centre chord as it passes. However, because of the dual coil configuration, even quite large rotational errors in the coil's alignment relative to the blade tips would have negligible effect on the crossing point of the two output signals. The coils axes, i.e. the axes around which the coils are wound, are aligned with the radial axis of the blades being sensed and at right angles to the turbine shaft. In other words, the axes point towards the turbine shaft.
[0035] The coils are wound in the same direction, with similar physical and electrical characteristics. The cross-sectional shape of each coil is typically oval or rectangular but can be chosen to suit the application. For thin blade sections the coils can be oval or rectangular to maximize the blade tip area influencing the coils. For thicker blades, round section coils may be adequate. Ideally, the coils sensing face width is about the same as the aligning part of the blade tip's width.
[0036] In typical configurations where the sensors may be employed on several different turbines, with similar blade thicknesses but different twist angles, a round sensor body can be beneficial. Using a rear clamp type mounting or a lockable flange, the sensor can be rotated to match the blade angle and then be locked in place.
[0037] The sensor housing may also contain part of the electronic processing circuitry such as the excitation oscillator and AM demodulator sections. This enables much longer sensor-to-processing electronics connecting cables to be employed and, also reduces RF emissions from the cables, because of the lower signal bandwidth.
[0038] One processing method for generating a timing signal for the turbine blades involves comparing the two demodulated signals and generating a timing edge as their amplitude levels cross. Because any drifts or other changes will essentially occur equally in each coil output, any errors are effectively tracked by the compared signals and hence have little effect on the timing of the crossing point. Any carrier feed-through noise remnants will be effectively nulled because the two signals will be of the same frequency and phase so will track each other at the comparator inputs.
[0039] FIG. 4 shows a simplified part-block diagram of a possible sensor processing configuration. The signals from each of the outputs 18 and 19 are first demodulating by half-wave envelope detector electronics 40 . The demodulated signals are then band pass filtered and amplified by suitable electronics 42 . Amplification and filtering remove any remnants of the sensor excitation carrier. The signals are then passed to a comparator 44 . This is arranged with single polarity positive feedback hysteresis. In the configuration shown in FIG. 4 , this causes the hysteresis to only be applied during negative comparator output swings. The hysteresis is blocked by the diode 46 during positive output swings so does not affect the switching threshold. This allows a voltage margin to inhibit triggering of the comparator when both signals are near the resting level. The comparator output can only swing positive when input 1 , derived from the first sensor coil 10 , falls below input 2 derived from the second sensor coil 11 , level minus the hysteresis. Once the comparator output has swung positive, the hysteresis is effectively removed. As a result the comparator output will switch negative when signals 1 and 2 cross, in the middle of the blade pass. This point is at the required Tip Timing point in the blade pass. This tip timing edge may then be used to trigger a pulse stretcher which will in turn generate a buffered tip timing output pulse of the required length and polarity.
[0040] FIG. 5 shows a typical waveform sequence, with the hysteresis points shown. The overlaid demodulated signals are shown above the output timing signal. A tip timing edge 50 is generated each time the amplitude of the two signals cross with output 1 rising and output 2 falling.
[0041] The signals from the coils could be demodulated in an inverted sense to that shown in FIG. 5 . In that case, the hysteresis would also be reversed, by reversing the blocking diode.
[0042] It should be appreciated that, although the present invention has been described with reference to an active eddy current sensor, it may be applicable to other types of inductive sensor in a turbine engine, such as passive eddy current sensors.
[0043] This present invention allows for simplified but improved tip timing sensor signal processing electronics. The invention greatly reduces the power requirements as compared with the prior art by removing the need for high speed signal peak-detectors. The present invention also reduces the effects of random noise in the analogue signals and improves overall EMC performance. | A method is provided for determining timing points indicative of the passage of a blade in a turbine engine. The method comprises the steps of: providing a s first sensing coil proximate to a path of the blade, providing a second sensing coil proximate to the path of the blade, the second sensing coil spaced from the first sensing coil in a direction parallel to the path of the blade, and comparing a signal generated in the first sensing coil with a signal generated in the second sensing coil to derive a timing point indicative of the passage of the blade. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to a method of increasing productivity of oil, gas and water wells.
Horizontal and inclined wells are usually directed along the extension of formations (strata) without taking into consideration the influence of rock pressure. This can lead to significant reduction of fluid flows, such as oil, gas and water flows. (1-10). In addition it does not provide a complete embrace of the formation, and in condition of great depths due to compressing ring-shaped stresses as in vertical well it is not always guaranteed that it will be possible to obtain the desired product (27). In these cases it is known to use hydrocracking of formation, chemical treatment and various methods of intensification (1, 6, 9, 11, 12, 4, 13, 14, 15, 9, 16, 5, 17 etc). In many cases the efficiency of these methods is insufficient and their realization is very expensive. The hydrocracking, chemical treatment, point perforation connect with a well bore only a part of formation, for a short time, since the produced spaces are retained under the same rock pressure and after a certain time close again. The utilized methods of intensification do not cover the whole working distance, they are expensive, and their effect disappears after a certain time.
The known intensification methods include the method of unloading with slots (19) which almost fully and permanently removes rock pressure from near-well zone. This increases efficiency of operation of the wells. However this method is not always efficient in horizontal and inclined well where a different mechanism of rock compression takes place, in which orientation of directions of perforation relative to main horizontal stresses, as well as a length and width of the cavities are important. In inclined wells it is known to carry our perforation by the method of slot unloading in a direction of maximum cracking of the near-well zone (20), upwards from the well, which is also not efficient, for example due to “clamping” of the cracks by ring shaped, tangential stresses of double concentration, produced around the perforation channels.
While maximum unloading of a well by a perforation takes place if a plane of a slot is oriented perpendicular to a main stress, the direction of the well is not coordinated with the main stress direction, and the unloading of the well bore will not be optimal. When the plane of the slot is close to maximum horizontal stress, the slot will not work at all and will be immediately compressed by the rock pressure. In the case of a random proper orientation of the perforation, the flow of fluid takes place only at the locations of the perforation (slots, cavities), but not along the whole length of the horizontal or inclined well.
SUMMARY OF THE INVENTION
Accordingly it is an object of the present invention to provide a method of increasing productivity of oil, gas and water wells, which is a further improvement of the existing methods.
In keeping with these objects and with others which will become apparent hereinafter, one feature of the present invention resides, briefly stated, in a method of increasing productivity of oil, gas or water wells, comprising the steps of excavating of a horizontal or inclined well, forming in the horizontal or inclined well a plurality of cavities which extend transversely to the direction of elongation of the horizontal or inclined well and are spaced from one another in a direction of elongation of the horizontal or inclined well so as to form a plurality of partitions therebetween, providing packing of the cavities between the partitions so as to separate the cavities from the horizontal or inclined well, and executing hydrocracking by acting onto the partitions located between the cavities inside the horizontal or inclined well.
Another feature of the present invention resides in that the method includes making the cavities as slot-shaped cavities which redistribute stresses in the rock so that a concentration of stresses around the horizontal or inclined wall is substantially removed and directed to edges of the slot-shaped cavities and an unloading corridor if formed in a direction of the slot-shaped cavity. The slot-shaped cavities can be made so that the partitions between them have a length l corresponding to the following equation:
l = k [ 12.5 + 3 ( σ 1 σ 3 ) 2 3 ] · d ( cm )
where
σ 1 , is a max horizontal stress at location of perforation, MPa,
σ 3 is a strength of productive formation in near-well zone, MPa,
d is a diameter of well (cm),
k=0.5-5.0 depending on geological conditions.
A further feature of the present invention resides in that the method includes making the cavities as disc-shaped cavities which redistribute stresses in the rock so that a concentration of stresses around the horizontal or inclined wall is substantially removed and directed to edges of the disc-shaped cavities and an unloading corridor if formed in a direction of the disc-shaped cavity. The disc-shaped cavities can be made so that the partitions between them have a length l corresponding to the following equation:
l = k [ 10 + 2 ( σ 1 σ 3 ) 2 3 ] · d ( cm )
where
σ 1 , is a max horizontal stress at location of perforation, MPa,
σ 3 is a strength of productive formation in near-well zone, MPa,
d is a diameter of well (cm),
k=0.5-5.0 depending on geological conditions.
When the method of increasing productivity of oil, gas and water wells is performed in accordance with the present invention it eliminates the disadvantages of the prior art and achieves the above-mentioned highly advantageous results.
The novel features which are considered as characteristic for the present invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 of the drawings is a view showing a selection of a direction of making a horizontal or inclined well in accordance with the present invention;
FIG. 2 of the drawings is a view showing a horizontal or inclined well with disc-shaped cavities in accordance with the present invention;
FIG. 3 of the drawings is a view showing a horizontal or inclined well with vertical slot-shaped cavities in accordance with the present invention;
FIGS. 4 a and 4 b of the drawings are views showing incorrect and correct orientation of vertical slot-shaped cavities, correspondingly, in accordance with the present invention;
FIGS. 5 a and 5 b of the drawings are views showing the selection of sizes and arrangement of the disc-shaped cavities and stress distribution, correspondingly, in accordance with the present invention;
FIGS. 6 a and 6 b of the drawings are views showing the selection of sizes and arrangement of the vertical slot-shaped cavities and stress distribution, correspondingly, in accordance with the present invention;
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In accordance with the present invention first a vertical well 2 extending to a productive formation is made. At the location of the vertical well a vector (direction and value) of a maximum horizontal stress of rock α 1 is determined by known means. Then a direction for a horizontal or inclined well 3 extending from the vertical well 2 is selected. In accordance with the present invention best results are obtained when the direction of a horizontal or inclined well is selected to be as close as possible along a transverse to the main maximum stress. It is acceptable to produce the horizontal or inclined well in a direction which deviates from the main maximum stress direction by 40 degrees at both sides of it, or in other words, ±40° as shown in FIG. 1 . Based on this concept, the horizontal or inclined well is made in a known manner, for example as disclosed in (23) of the list of sources below.
The horizontal or inclined well oriented along the main maximum horizontal stress is shown in FIG. 2 , while the horizontal or inclined well oriented transverse to the main maximum horizontal stress is shown in FIG. 3 . When the horizontal or inclined well is made in this manner, then slots cavities 4 are made. These cavities can be produced by a sand-blasting perforator, for example AP-6 (24). The sand-blasting provides ideal opening of the formation, does not damage cement or casing, and establishes an ideal communication between the well and rock of the formation.
The reduction of excessive (when compared with normal geostatic) stresses acting near the well leads to a possibility to increase permeability of productive formation and increase in flow of fluid to the well. The formation of the slots or cavities 4 causes redistribution of stresses. Concentration of stresses around the well is redistributed to the edges of the slots or cavities, and a corridor of unloading is formed in direction of the slot or cavity. The combination of the above mentioned selection of the direction of making the horizontal or inclined well relative to horizontal stresses with the orientation of the slot-shaped cavities increases the productivity of the well along its whole length and for a long time.
Since the horizontal or inclined well has a great length, cutting of continuous longitudinal slots is expensive and complicated. In the present invention the cavities are made to be spaced with one another and to leave a plurality of partitions P therebetween. The partitions P contribute to inflow of fluid and have sizes selected in a new inventive way. The cavities can be disc-shaped as shown in FIG. 2 or vertical slot-shaped as shown in FIG. 3 , and the distances between them are different. It is necessary that the partitions P between them stay not destroyed or in other words withstand the loads acting on them so they act as stamps, onto the surrounding rock, and in this case the fluid is pressed from the productive formation into the cavities and into the well. The length of the partition P must be not greater than double width of the zone of pressure formed from each of neighboring adjacent cavities.
For the partitions between the disc-shaped cavities the length of the partitions in the inventive method is selected as:
l = k [ 10 + 2 ( σ 1 σ 3 ) 2 3 ] · d ( cm )
where
σ 1 , is a max horizontal stress at location of perforation, MPa,
σ 3 is a strength of productive formation in near-well zone, MPa,
d is a diameter of well (cm),
k=0.5-5.0 depending on geological conditions.
For the partitions between the vertical slot-shaped cavities the length of the partition in the inventive method is selected as:
l = k [ 12.5 + 3 ( σ 1 σ 3 ) 2 3 ] · d ( cm )
where
σ 1 , is a max horizontal stress at location of perforation, MPa,
σ 3 is a strength of productive formation in near-well zone, MPa,
d is a diameter of well (cm),
k=0.5-5.0 depending on geological conditions.
FIG. 4 shows the horizontal or inclined well, the slots or cavities 4 , and zones of pressure 5 , with the left illustration showing incorrect location of the slots or cavities and the right illustration showing correct location of the slots of cavities.
FIGS. 5 and 6 illustrate correspondingly the disc-shaped cavities and the slot-shaped cavities with the partitions therebetween, and the distribution of the stresses in the partitions.
In accordance with the present invention, the depth and thickness of the cavities 4 is selected for their optimization. On one hand the cavities must unload the ring-shaped stresses around the horizontal or inclined well, while on the other hand their perforation is complicated and expensive. In view of the fact that the disc-shaped cavities and vertical slot-shaped cavities act in different ways, their dimensions are selected in different ways.
The disc-shaped cavities must have the depth of more than 2 well diameters and the thickness not less than 2 cm, while the vertical slot-shaped cavities must have the depth of more or equal to 2 well diameters and the thickness not less than 3 cm. A decrease of these sizes leads to a change in flow of fluid, while their increase leads to abnormal complexity and cost of work. In accordance with the invention, borders of the tectonically stressed zones are determined, in these zones the value of maximum main horizontal stress and the strength of the productive layer are determined, and depending on these values the dimensions of the cavities and activating partitions therebetween are determined in these zones.
After the formation of the cavities in the horizontal or inclined well and packing by packers in the horizontal or included well, hydrocracking is performed of the activated partitions successively.
The inventive method has been tested on experimental model, with the productive formation located at a depth of 1,200-1,201.5 m, well length 120 m, (σ 1 )=30 MPa and (σ 3 )=60 MPa,
Table 1 shows the results.
TABLE 1
CHANGE OF
CAVITIES
INTECTONIC
DIRECTION
SLOT-SHAPED
STRESSED
YIELD
OF WELL
CAVITIES
ZONES
SLOTS
A DAY
1. Along max.
No
No
Yes
100-200
main
horizontal
stress
2. +40 from 1
No
No
Yes
70-120
3. −40 from 1
No
No
Yes
70-100
4. Transverse
No
No
Yes
200-300
max horizontal
stress
5. +40 of 1
No
No
Yes
120-200
6. −40 of 1
No
No
Yes
120-150
7. As 1
Yes
No
No
1000-1500
8. As 1
Yes
No
Yes
900-1500
9. As 2
Yes
No
Yes
600-800
10. As 3
Yes
No
Yes
600-800
11. As 4
Yes
No
Yes
2000-2500
12. As 4
Yes
No
No
1700-2000
13. As 5
Yes
No
Yes
1200-1600
14. As 6
Yes
No
Yes
1100-1500
15. As 10
Yes
No
Yes
1100-1500
16. As 10
Yes
Yes
Yes
1100-1700
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of methods differing from the types described above.
While the invention has been illustrated and described as embodied in a method of increasing productivity of oil, gas and water wells, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.
What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.
LIST OF SOURCES
1. U.S. Pat. No. 5,074,360.
2. U.S. Pat. No. 4,658,588.
3. U.S. Pat. No. 4,669,546.
4. U.S. Pat. No. 5,016,709.
5. U.S. Pat. No. 4,388,286.
6. U.S. Pat. No. 474,850.
7. SU 1677278.
8. SU 1677274.
9. U.S. Pat. No. 6,842,652.
10. U.S. Pat. No. 4,883,124.
11. U.S. Pat. No. 435,756.
12. SU 1601354.
13. U.S. Pat. No. 4,696,345.
14. U.S. Pat. No. 4,702,315.
15. U.S. Pat. No. 467,788.
16. U.S. Pat. No. 4,718,100.
17. SU 1740564.
18. U.S. Pat. No. 5,010,964.
19. Geology Methods of Search and Investigation of Oil and Gas Deposits, Express Information 8-9, 1977.
20. U.S. Pat. No. 5,074,359.
21. U.S. Pat. No. 4,909,336.
22. GEODYNAMIC REGIONING OF GROUND, L., GROUND 1990.
23. V. A. Sidorovsky. Opening of Formations and Increase of Well Productivity, M., Ground, 1978.
24. Works for Permeability Increase of Oil-Containing Formations with Slot Unloading Geology, Search and Investigation of Oil and Gas Formation Express-Information, VNIIOENG 1977.
25. Petukhov I. M. Theory of Protective Formations, M. Ground, 1976.
26. Petukhov I. M., M. Ground, 1992.
27. U.S. Pat. No. 5,337,825.
28. SU2079643. | For increasing productivity of oil, gas and water wells, a horizontal or inclined well is excavated, a plurality of cavities are formed transversely to the direction of elongation of the well so as to provide partitions between them, and hydrocracking is carried out to act on the partitions between the cavities. | 4 |
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0001] Not applicable.
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER LISTING APPENDIX
[0002] Not applicable.
COPYRIGHT NOTICE
[0003] 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 patent disclosure as it appears in the Patent and Trademark Office, patent file or records, but otherwise reserves all copyright rights whatsoever.
FIELD OF THE INVENTION
[0004] One or more embodiments of the invention generally relate to female undergarments for post mastectomy wear. More particularly, the invention relates to single sided breast support and achieving a symmetrical breast appearance.
BACKGROUND OF THE INVENTION
[0005] The following background information may present examples of specific aspects of the prior art (e.g., without limitation, approaches, facts, or common wisdom) that, while expected to be helpful to further educate the reader as to additional aspects of the prior art, is not to be construed as limiting the present invention, or any embodiments thereof, to anything stated or implied therein or inferred thereupon.
[0006] A mastectomy is a surgical procedure that involves the removal of a breast, with a subsequent asymmetrical appearance. Following mastectomy, a regular bra cannot be worn due to tenderness, as it constricts the surgical area and interferes with drainage tubing from the surgical area. This leaves the healthy breast unsupported. Current mastectomy camisoles available cannot be worn for about six weeks, and provide no support to the remaining breast. Mastectomy bras with prostheses cannot be worn until healing is complete, after more than two months.
[0007] In view of the foregoing, it is clear that these traditional techniques are not perfect and leave room for more optimal approaches.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:
[0009] FIGS. 1A and 1B illustrate an exemplary single cup bra, in accordance with an embodiment of the present invention. FIG. 1A is a diagrammatic front view, and FIG. 1B is a diagrammatic rear view; and
[0010] FIGS. 2A through 2C illustrate an exemplary camisole, in accordance with an embodiment of the present invention. FIG. 2A is a diagrammatic front view. FIG. 2B is a partially transparent rear view, and FIG. 2C is a diagrammatic side view.
[0011] Unless otherwise indicated illustrations in the figures are not necessarily drawn to scale.
SUMMARY OF THE INVENTION
[0012] To achieve the forgoing and other objects and in accordance with the purpose of the invention, a variety of specialized undergarments for post mastectomy surgery is described.
[0013] In one embodiment, the garment for post mastectomy surgery comprises a waistband configured to fit about a waist of the woman. A strap is joined to the waistband and is configured to extend diagonally from the waistband below the site of the mastectomy, up over a shoulder to the side opposite the surgery, and down to the waistband on the surgery side in the back. A bra cup comprises a first side, a bottom side, and a second side, configured to fit about the woman's remaining breast. A first strap is configured to laterally join the first side of the bra cup to the strap on the woman's front. A second strap is configured to laterally join the second side of the bra cup to the strap on the woman's back. An elastic panel is configured to join to the strap, the bottom side of the bra cup, the first diagonal strap, the second lateral strap, and the waistband where the elastic paneling positions the bra cup to support the remaining breast. Another embodiment further comprises a panel being configured to join to the strap, the top of the bra cup, the first strap and the second strap. In yet another embodiment the second lateral strap further comprises a rib support for mitigating curling or bunching of that strap. In still another embodiment the strap comprises a mechanism joined to the strap near the shoulder. The mechanism is configured to adjust a length of the shoulder strap. In another embodiment the mechanism is further configured to separate the strap into two pieces. In yet another embodiment the waistband is further configured to be adjustable. Still another embodiment further comprises a camisole being configured to be draped over at least the waistband, the strap, the bra cup, the first strap, the second strap and the elastic panel. In another embodiment the camisole comprises a front and a back. The back comprises a back panel. The front comprises two front panels being joined to the back panel. In yet another embodiment each front panel comprises one breast pocket being configured to accept insertion of a breast form above a site of the surgery. In still another embodiment each front panel also comprises at least one pocket being configured to be operable to hold surgical drainage tubes. In another embodiment the front panel comprises, a first front panel and a second front panel being removably joined together to open the front panel.
[0014] In another embodiment garment for post mastectomy surgery comprises means for securing a piece of the garment about a waist of the woman, means for supporting the piece of the garment on a shoulder on a side opposite the surgery, means for fitting about the remaining breast, means for laterally joining the fitting means to the supporting means, means for elastically joining the securing means, the supporting means, the fitting means and the laterally joining means to position the fitting means to support the remaining breast, and means for draping over the securing means, the supporting means, the fitting means, the laterally joining means and the elastically joining means. Another embodiment further comprises means for supporting a breast form above a site of the surgery. Yet another embodiment further comprises means for holding surgical drainage tubes.
[0015] In another embodiment a camisole for post mastectomy surgery comprises a back comprising a back panel. A front comprises left and right front panels being joined to the back panel. One e breast pocket is joined to each front panel. Each breast pocket is configured to accept insertion of a breast form above a site of the surgery. Another pocket on each panel is configured to be operable to hold surgical drainage tubes. In another embodiment each breast pocket is disposed on an inside portion of the front panel. In still another embodiment the front panel comprises a first front panel and a second front panel being removably joined together to open or close the front panels. In another embodiment the front comprises a V-shaped neckline. In yet another embodiment the back comprises a V-shaped neckline.
[0016] Other features, advantages, and objects of the present invention will become more apparent and be more readily understood from the following detailed description, which should be read in conjunction with the accompanying drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] The present invention is best understood by reference to the detailed figures and description set forth herein.
[0018] Embodiments of the invention are discussed below with reference to the Figures. However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes as the invention extends beyond these limited embodiments. For example, it should be appreciated that those skilled in the art will, in light of the teachings of the present invention, recognize a multiplicity of alternate and suitable approaches, depending upon the needs of the particular application, to implement the functionality of any given detail described herein, beyond the particular implementation choices in the following embodiments described and shown. That is, there are numerous modifications and variations of the invention that are too numerous to be listed but that all fit within the scope of the invention. Also, singular words should be read as plural and vice versa and masculine as feminine and vice versa, where appropriate, and alternative embodiments do not necessarily imply that the two are mutually exclusive.
[0019] It is to be further understood that the present invention is not limited to the particular methodology, compounds, materials, manufacturing techniques, uses, and applications, described herein, as these may vary. It is also to be understood that the terminology used herein is used for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention. It must be noted that as used herein and in the appended claims, the singular forms “a,” “an,” and “the” include the plural reference unless the context clearly dictates otherwise. Thus, for example, a reference to “an element” is a reference to one or more elements and includes equivalents thereof known to those skilled in the art. Similarly, for another example, a reference to “a step” or “a means” is a reference to one or more steps or means and may include sub-steps and subservient means. All conjunctions used are to be understood in the most inclusive sense possible. Thus, the word “or” should be understood as having the definition of a logical “or” rather than that of a logical “exclusive or” unless the context clearly necessitates otherwise. Structures described herein are to be understood also to refer to functional equivalents of such structures. Language that may be construed to express approximation should be so understood unless the context clearly dictates otherwise.
[0020] Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. Preferred methods, techniques, devices, and materials are described, although any methods, techniques, devices, or materials similar or equivalent to those described herein may be used in the practice or testing of the present invention. Structures described herein are to be understood also to refer to functional equivalents of such structures. The present invention will now be described in detail with reference to embodiments thereof as illustrated in the accompanying drawings.
[0021] From reading the present disclosure, other variations and modifications will be apparent to persons skilled in the art. Such variations and modifications may involve equivalent and other features which are already known in the art, and which may be used instead of or in addition to features already described herein.
[0022] Although Claims have been formulated in this Application to particular combinations of features, it should be understood that the scope of the disclosure of the present invention also includes any novel feature or any novel combination of features disclosed herein either explicitly or implicitly or any generalization thereof, whether or not it relates to the same invention as presently claimed in any Claim and whether or not it mitigates any or all of the same technical problems as does the present invention.
[0023] Features which are described in the context of separate embodiments may also be provided in combination in a single embodiment. Conversely, various features which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination. The Applicants hereby give notice that new Claims may be formulated to such features and/or combinations of such features during the prosecution of the present Application or of any further Application derived therefrom.
[0024] References to “one embodiment,” “an embodiment,” “example embodiment,” “various embodiments,” etc., may indicate that the embodiment(s) of the invention so described may include a particular feature, structure, or characteristic, but not every embodiment necessarily includes the particular feature, structure, or characteristic. Further, repeated use of the phrase “in one embodiment,” or “in an exemplary embodiment,” do not necessarily refer to the same embodiment, although they may.
[0025] As is well known to those skilled in the art many careful considerations and compromises typically must be made when designing for the optimal manufacture of a commercial implementation any system, and in particular, the embodiments of the present invention. A commercial implementation in accordance with the spirit and teachings of the present invention may configured according to the needs of the particular application, whereby any aspect(s), feature(s), function(s), result(s), component(s), approach(es), or step(s) of the teachings related to any described embodiment of the present invention may be suitably omitted, included, adapted, mixed and matched, or improved and/or optimized by those skilled in the art, using their average skills and known techniques, to achieve the desired implementation that addresses the needs of the particular application.
[0026] It is to be understood that any exact measurements/dimensions or particular construction materials indicated herein are solely provided as examples of suitable configurations and are not intended to be limiting in any way. Depending on the needs of the particular application, those skilled in the art will readily recognize, in light of the following teachings, a multiplicity of suitable alternative implementation details.
[0027] A practical embodiment of the present invention provides single sided breast support for women post mastectomy that can be worn immediately after surgery. Many practical embodiments also comprise a camisole overlay with pockets for breast forms to replace an absent breast. Many practical embodiments provide support to the healthy breast after surgery and do not constrict the surgical area. Also, these embodiments are easy to put on unlike current mastectomy camisoles that are often snug on the body and may need to be put on or taken off over the head. Traditional camisoles usually cause overheating of the body, particularly with menopausal women.
[0028] FIGS. 1A and 1B illustrate an exemplary single cup bra 100 , in accordance with an embodiment of the present invention. FIG. 1A is a diagrammatic front view, and FIG. 1B is a diagrammatic rear view. In the present embodiment, bra 100 comprises a diagonal strap 105 extending from a waistband 110 in front, over the shoulder and to waistband 110 in back. A single bra cup 115 is connected to the front of strap 105 by a connecting band 120 and to the back of strap 105 by a connecting band 125 . Elastic paneling 130 connects bra cup 115 and connecting band 120 to waistband 110 in front and back to stabilize cup 115 and generally prevent shifting.
[0029] The design of strap 105 , which extends from the side of the mid abdomen in front below a surgical site 135 up to the shoulder of the non-affected side, enables bra 100 to be worn after surgery since surgical site 135 is typically not touched. Strap 105 is adjustable and opens and closes with a sliding clasp 140 near the shoulder. Some alternate embodiments may use a multiplicity of suitable fastening means such as, but not limited to, snaps, hooks, hook and loop material etc. In other alternate embodiments, the strap may not be adjustable or may not be able to be fastened or unfastened. In the present embodiment, waistband 110 is adjustable and located near the lower mid abdomen to stabilize bra 100 and generally prevent riding up. Waistband 110 may comprise various different means for adjustable closure such as, but not limited to, hook and loop material, buckles, hooks and eyes, sliding clasps, etc. Some alternate embodiments may comprise separate means for adjusting the belt and fastening the belt. In the present embodiment, waistband 110 is approximately one inch wide and diagonal strap 105 is approximately ½ inch wide; however, the waistbands and straps in alternate embodiments may be narrower or wider. In some alternate embodiments, an additional strap may be added that connects to the mid portion of the back of the diagonal strap and crosses over the shoulder on the surgical side to connect to the upper third of the front of the diagonal strap. This embodiment creates a V-design near the neck in the front and back and may provide additional support.
[0030] In the present embodiment, connecting bands 120 and 125 connect cup 115 to diagonal strap 105 for greater stability. Those skilled in the art, in light of the teachings of the present invention will readily recognize that a multiplicity of suitable materials may be used for connecting bands 120 and 125 such as, but not limited to mesh, elastic banding, fabric, etc. In the present embodiment, connecting band 125 comprises a rib support 145 to generally prevent curling or bunching of connecting band 125 . However, this rib support may be omitted in some alternate embodiments. In the present embodiment, a panel 150 connects the top of cup 115 and the top of connecting band 125 to diagonal band 105 . Panel 150 may be made of various different materials such as, but not limited to, elastic mesh, cotton, lace, elastic fabrics, etc. Some alternate embodiments may be implemented without this panel. In the present embodiment, bra cup 115 is typically made of standard fabrics and lingerie materials currently available and may or may not comprise an under wire. Paneling 130 may be made of various different materials such as, but not limited to, elastic mesh, lace, cotton, etc. Some alternate embodiments may be implemented without paneling below the bra cup extending around the body to the diagonal strap in back. Those skilled in the art, in light of the teachings of the present invention, will readily recognize that a multiplicity of suitable trims and decorations may be included, without limitation, on some embodiments. For example, without limitation, elastic lace covering may be placed on the diagonal strap in front and back, decorative buttons or snaps may be used for the fasteners, a design may be placed on the waistband near the closure with a monogram or embellishment, etc.
[0031] In typical use of the present embodiment, bra 100 is worn around the waist and the non-affected shoulder of a user 155 . The adjustable diagonal design from above the hip to the opposite shoulder and diagonally down to the lower back allows for post-surgical drainage tubes 160 and surgery site 135 to be unaffected while providing support to the remaining healthy breast.
[0032] FIGS. 2A through 2C illustrate an exemplary camisole 200 , in accordance with an embodiment of the present invention. FIG. 2A is a diagrammatic front view. FIG. 2B is a partially transparent rear view, and FIG. 2C is a diagrammatic side view. In the present embodiment, camisole 200 is a sleeveless garment comprising a large back panel 205 and two front panels 210 each stitched to back panel 205 at the sides. Panels 205 and 210 are made of a lightweight, breathable, typically sheer material such as, but not limited to, open mesh fabric or lace. However, various different materials may be used such as, but not limited to, cotton, satin, silk, blends, etc. Camisole 200 opens and closes at the front with fastening means 213 such as, but not limited to, snaps, hooks, buttons, hook and loop material, etc. An opaque area 215 over the bust comprises hidden pockets 220 on the inside of camisole 200 into which breast forms may be inserted. In some alternate embodiments, this area may be sheer rather than opaque. In other alternate embodiments, the entire camisole may be opaque. In the present embodiment, two pockets 225 located on the inside of camisole 200 near the side seams can be used to hold and conceal drainage tubes and containers near the waist area. In addition, drainage tubes may be pinned to a fabric edging 230 around the bottom of camisole 200 . In some alternate embodiments, the pockets may be placed on the front of the camisole instead of the sides. In other alternate embodiments, the pockets may be placed on the outside of the camisole. Other alternate embodiments may comprise more or fewer pockets. Yet other alternate embodiments may be implemented without pockets for drainage tubes. Furthermore, some alternate embodiments may be implemented without a fabric edging around the bottom. In the present embodiment camisole 200 comprises a V-shaped neckline 235 in the front and back; however, some alternate embodiments may have necklines of various different shapes including, without limitation, a modified to scoop neck, a front V-neck only, a square neck, etc. It is contemplated that some embodiments of the present invention may comprise a multiplicity of suitable trim or details for decoration such as, but not limited to, lace edgings, decorative buttons or snaps, ribbons, panels of fabrics added to the back and front, etc.
[0033] In typical use of the present embodiment, camisole 200 is worn over a single cup bra 201 . Together, single cup bra 201 , camisole 200 and a breast form inserted into a pocket 220 can achieve a comfortable, symmetrical look, without interfering with sutures, drains or healing. The breathable fabric allows for air circulation to keep the user cool and to support healing. Additionally, V-shaped neckline 235 minimizes surface area contact with the skin. Frontal access and closure generally makes putting on and taking off camisole 200 easy. The loose fit of camisole 200 generally ensures that there is no constriction or pressure near tender areas or drainage tubes so that camisole 200 can be worn immediately following surgery. Furthermore, camisole 200 can be worn with a breast insert and without a bra, for example, without limitation, at night under a nightgown, to achieve symmetry. Camisole 200 may also be worn with or without a bra and without a breast insert.
[0034] All the features disclosed in this specification, including any accompanying abstract and drawings, may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.
[0035] Having fully described at least one embodiment of the present invention, other equivalent or alternative methods of providing single breast support according to the present invention will be apparent to those skilled in the art. The invention has been described above by way of illustration, and the specific embodiments disclosed are not intended to limit the invention to the particular forms disclosed. For example, the particular implementation of the bra may vary depending upon the particular type of camisole used. The camisoles described in the foregoing were directed to separate overlay implementations; however, similar techniques are to provide camisoles that are permanently attached to the bra or may be removably attached to the bra by various different means including, without limitation, hooks, snaps, hook and loop material, etc. Connected implementations of the present invention are contemplated as within the scope of the present invention. The invention is thus to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the following claims.
[0036] Claim elements and steps herein may have been numbered and/or lettered solely as an aid in readability and understanding. Any such numbering and lettering in itself is not intended to and should not be taken to indicate the ordering of elements and/or steps in the claims. | A garment for a post mastectomy surgery woman comprises a waistband fits about a waist of the woman. A strap is joined to the waistband to extend from the waistband at a side of the woman's surgery, up over a shoulder on a side opposite the surgery and down to the waistband on the surgery side. A bra cup is configured to fit about the woman's healthy breast. A first strap is configured to laterally join a first side of the bra cup to the strap on the woman's front. A second strap is configured to laterally join a second side of the bra cup to the strap on the woman's back. An elastic paneling is configured to join to the strap, the bottom side of the bra cup, the first strap, the second strap, and the waistband. The elastic paneling positions the bra cup to support the woman's healthy breast. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority, under 35 U.S.C. 119, of earlier-filed Italian Application TO2001A000133, filed Feb. 15, 2001.
BACKGROUND OF THE DISCLOSURE
[0002] The present invention relates to a rocker arm for valve trains of internal-combustion engines, and more particularly, to rocker arms for use in valve gear trains of the “end-pivot” rocker arm type.
[0003] For a better understanding of the state of the art regarding the subject in question and the problems relating thereto, firstly a rocker arm of known design will be described, with reference to FIGS. 6, 7A and 7 B of the accompanying drawings.
[0004] [0004]FIG. 6 is a view, partially sectioned longitudinally, of a valve train, generally designated 1 , which is able to cause the alternating rectilinear movement of an engine poppet valve (only a stem 20 of the valve being shown in FIG. 6) in accordance with a predetermined opening sequence. The valve train comprises a rocker arm 2 , a hydraulic tappet 3 and a cam-type actuating member 4 .
[0005] The mutual arrangement of the above-described components may vary depending on the type of engine and the type of distribution chosen. In particular the present invention relates to rocker arms of the type comprising end portions 5 and 6 able to engage the tappet 3 and the valve, respectively, and an intermediate portion 7 intended to receive a roller 8 co-operating with the cam-type actuating member 4 . An example of an embodiment of a rocker arm of this type is illustrated in detail in FIGS. 7A and 7B which show longitudinally sectioned and cross sectional views thereof, respectively.
[0006] The operating principle of a valve train of the above-mentioned type is well-known to a person skilled in the art: the rotational movement of a cam shaft (which is not shown, but which rotates the cam-type actuating member 4 ) is converted into the alternating rectilinear movement of the valve. Such rectilinear movement is the result of the interaction between the cam member 4 , having a base circle portion 9 and an eccentric profile (lift portion) 10 , and the roller 8 of the rocker arm, said interaction acting so as to cause oscillation of the rocker arm in its own longitudinal plane of symmetry (coinciding with the plane of the sheet showing FIG. 6), about a fulcrum point located in the zone of contact between the rocker arm 2 and the tappet 3 .
[0007] At present this type of rocker arm is advantageously produced by means of the operations of:
[0008] (a) shearing of a shaped element 30 (see FIG. 8), from a sheet of steel with a low carbon content, the element 30 having a form symmetrical with respect to a longitudinal axis 35 and being provided with an opening 36 , in a substantially intermediate position, and with two holes 21 and 22 situated laterally with respect to the opening 36 ;
[0009] (b) pressing the above-mentioned shaped element 30 in order to perform bending upwards (or downwards) of lateral portions 31 and 32 , along bending lines 33 and 34 , respectively, so as to provide the part with a substantially U-shaped cross section (see FIG. 7B), having a horizontal plate portion 11 which connects two vertical side walls 12 and 13 ;
[0010] (c) forming the horizontal plate portion 11 , at the end 5 of the rocker arm, so as to produce a partly spherical portion 14 having a concave surface of revolution 15 with an essentially ogive-shaped section able to engage with an essentially hemispherical convex outer surface 16 at the top of the hydraulic tappet 3 ;
[0011] (d) forming the above-mentioned horizontal plate portion 11 , at the end 6 of the rocker arm, so as to produce a shoe element 17 having a surface 18 with its concavity directed downwards and an arched cross section (in the plane of oscillation of the rocker arm), able to interact with the top (tip) 19 of the stem 20 of the engine poppet valve; and
[0012] (e) inserting and locking a cylindrical pin 23 in the two seats defined by the above-mentioned holes 21 and 22 , the roller 8 being rotatably mounted on the pin 23 by means of rolling elements 24 so as to project partially from the opening 36 in order to engage with the cam member 4 .
[0013] The shape and dimensions of the rocker arm 2 are dictated by the design requirements of the engine manufacturer and must therefore be able to satisfy precise geometrical constraints associated with predetermined positions, in the engine cylinder head, of the other valve train elements with which the rocker arm 2 must co-operate. The geometrical constraints determine the arrangement, in the plane of longitudinal symmetry of the rocker arm (coinciding with its plane of oscillation), of three significant points A, B and C, indicated in FIG. 6, as follows:
[0014] A is a center of the theoretical circumference (or hemisphere) of contact between the engaging surfaces 15 and 16 of the rocker arm 3 and the tappet 4 , respectively;
[0015] B is a center of the pin 23 of the roller 8 ; and
[0016] C is a theoretical point of contact between the contact surface 18 of the rocker arm 2 and the contact surface on the valve tip 19 of the valve stem 20 .
[0017] If the design requirements of the engine cylinder head result in the positioning of the above-mentioned point B at a sufficiently large lateral distance from the straight line passing through the other two points A and C at the opposite end zones 5 and 6 of the rocker arm 2 , respectively, the rocker arm may be manufactured by means of simple shearing and bending operations, with low production costs.
[0018] In order to clarify this point, it should be noted, with reference to FIG. 8, how the central opening 36 of the semi-finished product 30 has an elongated shape in the longitudinal direction, with an intermediate section 37 having a transverse dimension, or width, which is smaller than that of two longitudinal end sections 38 and 39 and how the two holes 21 and 22 are positioned opposite the above-mentioned intermediate section 37 . The width of the intermediate section 37 of the opening 36 cannot be less than a certain minimum value imposed by the technological constraints associated with the feasibility of the shearing operation. Consequently, the width of internal flanges 41 and 42 located between the intermediate section 37 and the holes 21 and 22 , respectively, has an upper limit value, once the dimensions of the above-mentioned holes and their distance from the axis 35 have been fixed.
[0019] In the design situation where the center B of the pin 23 is located underneath the straight line joining the end points A and C, the operation of bending of the lateral portions 31 and 32 of the semi-finished product 30 into a “U” is performed downwards, along the bending lines 33 and 34 . These bending lines, viewed in the longitudinal plane of symmetry of the rocker arm, are substantially parallel to the straight line passing through the points A and C. Observing, in FIG. 8, the geometry of the shaped element 30 , it can be easily understood that, if the distance of the point B from the straight line passing through the points A and C is fairly large, then the maximum width of the flanges 41 and 42 is sufficient to perform the function of laterally containing the rolling elements 24 (usually rollers) of the roller 8 .
[0020] When, on the other hand, the center of the pin 23 (point B) must be located above the straight line joining the end points A and C, the above-mentioned operation of bending into a “U” shape is performed upwards, again along the lines 33 and 34 . The two internal flanges 41 and 42 are thus positioned, at the end of bending, underneath the holes 21 and 22 of the pin and therefore must no longer perform the function of laterally containing the rolling elements of the roller, but must ensure the necessary flexural stiffness of the rocker-arm body. If, therefore, the distance of the point B from the straight line A-C, i.e. the distance of the centers of the holes 21 and 22 from the bending lines 33 and 34 , respectively, is too small, the maximum width of the flanges 41 and 42 may not be sufficient to provide the rocker arm with the required rigidity.
[0021] The problem of how to produce a rocker arm by means of pressing therefore arises, in particular, when the design constraints require a substantially aligned position of the three above-mentioned points A, B and C, i.e. essentially the top of the tappet, center of the roller and top of the valve stem.
[0022] Known prior art solutions envisage in this case the bending, for example downwards, of the lateral portions 31 and 32 of a shaped element 30 similar to that of FIG. 8, along bending lines which, viewed in the plane of longitudinal symmetry of the rocker arm, no longer substantially coincide with the straight line passing through the end points A and C, but are inclined upwards through an angle such as to ensure a width of the flanges 41 and 42 sufficient for performing the function of containing the rolling elements of the roller. It is therefore necessary to perform a further operation involving plastic deformation in order to displace the end portion 5 of the horizontal plate portion 11 of the rocker arm, which at the end of this first operation is still located aligned with the bending line, downwards as far as the level of the point C. This process is costly since it requires the use of presses capable of generating very high forces.
BRIEF SUMMARY OF THE INVENTION
[0023] Accordingly, it is an object of the present invention to provide a rocker arm which, even in the case of substantially aligned positioning of the above-mentioned three points A, B and C, may be produced through simple bending into a “U” shape by means of pressing without the need for further plastic deformation operations which produce a relative displacement of the end portions 5 , 6 and the intermediate portion 7 of the rocker arm.
[0024] These and other objects and advantages, which will emerge more clearly from the following description, are achieved by providing an improved rocker arm of the type constructed by means of deformation of a shaped element made of metallic material, comprising surfaces for engagement with a tappet and with a stem of a valve, respectively, and a portion for mounting of a rotatable roller, able to co-operate with a cam-type actuating member.
[0025] The improved rocker arm is characterized by the fact that the surface of engagement with the hydraulic tappet is formed in an insert fixed to the rocker arm. In accordance with a more limited aspect of the invention, the insert is formed, dimensioned, and positioned so that the surface for engagement with the tappet is essentially aligned with the roller and with the surface for engagement with the poppet valve.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The invention will be described in greater detail below, purely by way of a non-limiting example, with reference to the accompanying drawings in which:
[0027] [0027]FIG. 1 is a partially longitudinally sectioned view of a valve train provided with a rocker arm according to the invention;
[0028] [0028]FIGS. 2 a , 2 b and 2 c are, respectively, a longitudinally sectioned view, a laterally sectioned view, and a top plan view of the rocker arm according to FIG. 1;
[0029] [0029]FIG. 3 is a bottom perspective view of the rocker arm of the present invention according to FIG. 1;
[0030] [0030]FIG. 4 is a bottom perspective view of the body of the rocker arm according to FIG. 1, without the roller or the insert;
[0031] [0031]FIG. 5 is a sectioned perspective view of an insert able to be fastened to the rocker arm according to FIG. 1;
[0032] [0032]FIG. 6 is a partially longitudinally sectioned view of a valve train provided with a rocker arm of the conventional type;
[0033] [0033]FIGS. 7A and 7B are, respectively, a longitudinally sectioned view and a cross sectional view of the rocker arm according to FIG. 6; and
[0034] [0034]FIG. 8 is a plan view of a semi-finished article for production of the body of a rocker arm made in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0035] In the following description, only the elements and parts of specific importance and interest for the purposes of understanding the invention will be illustrated in detail; as regards, however, elements and parts not mentioned or considered, reference should be made to the solutions of the known type.
[0036] [0036]FIG. 1 shows a valve train 1 in which the geometric arrangement of its elements is such as to involve a substantial alignment of the three significant points A, B and C previously defined with reference to a known example of a prior art embodiment. The valve train comprises a rocker arm 2 of the same type as that shown in FIG. 6, but with the difference that, according to the invention, the concave surface 15 with an ogive-shaped cross section, able to engage with the respective surface 16 of the hydraulic tappet 3 , is formed in an insert 25 produced separately and fixed to the end portion 5 of the rocker arm, instead of being formed directly on this portion by means of a plastic deformation process.
[0037] The point A at the center of the theoretical circumference (or hemisphere) of contact between the concave surface 15 , formed in the insert 25 , and the surface 16 of the top of the tappet is substantially aligned with the center of the roller 8 and with the point C of theoretical contact between the surface 18 of the rocker arm and the top 19 of the valve stem 20 .
[0038] The insert 25 , which may be advantageously made by means of cold-pressing (cold forming) from a material which is not necessarily identical to that used for the body of the rocker arm 2 , has preferably a parallelepiped shape. The insert 25 has two flat side faces 26 and 27 (FIG. 5) able to mate with respective inner faces 12 a and 13 a (visible in FIG. 4) of the side walls 12 and 13 in the end portion 5 of the rocker arm.
[0039] With reference still to FIG. 5, in which a preferred embodiment of the insert 25 is shown, it can be seen how, in order to facilitate assembly and engagement with the rocker arm, the insert has, on its upper side 28 , a lug 29 . The lug 29 is able to be inserted into, and mate with, a hole 45 formed in the horizontal plate portion 11 of the rocker arm in the zone where the insert 25 is housed. The lug 29 may either have only a positioning and centering function during assembly of the insert or form an actual fastening element co-operating with the body of the rocker arm. In this latter case, the lug 29 has a height preferably greater than the thickness of the sheet metal of the rocker arm body, so that once inserted inside the hole 45 , an upper end portion extends beyond the upper wall of the horizontal plate portion 11 and is thus capable of being fixed to the wall. This fixing operation may be performed in conventional ways, known to a person skilled in the art, which are simple to perform and not costly, for example, by means of crushing or riveting.
[0040] It can therefore be understood how, with a rocker arm according to the invention, it is possible to satisfy fully the design specifications imposed by the engine manufacturer, in terms of geometrical and mechanical characteristics, by means of simple and high-productivity machining operations which can be performed using machines which do not require a high initial outlay. In particular, the adoption of an insert produced separately from the body of the rocker arm means that it is no longer required to perform further plastic deformation operations which require the use of presses capable of generating high pressing forces and therefore having a correspondingly high cost. According to the present invention, in fact, these plastic deformation operations are replaced by cold-pressing of the insert, with the formation of its concave surface having an ogive-shaped cross section (although those skilled in the art will understand that such a shape is by way of example only), and by fixing the insert to the rocker arm body. Such fixing may be advantageously performed, in the case of an insert provided with the mating lug 29 , by means of the same type of operation used for locking the pin of the roller in the two holes of the rocker arm body, for example by riveting the top end of the above-mentioned lug 29 in order to produce wedging thereof by means of interference inside the corresponding hole 45 .
[0041] Another advantage of the rocker arm of the present invention is the “modular” design, because it is possible to use the same type of insert for rocker arms with different shapes and/or dimensions or, vice versa, use inserts with different shapes and/or dimensions for the same type of rocker arm.
[0042] It is also possible to manufacture the insert 25 from a material which is different or is treated differently from the shoe 17 , so as to satisfy the opposing requirements arising from the two couplings, i.e. the insert/tappet coupling and the shoe/stem coupling. In the first case, in fact, the coupling between the concave ogive-shaped surface of revolution 15 of the insert and the substantially hemispherical surface 16 of the tappet produces low contact stresses, but high frictional wear; on the other hand, the coupling between the convex surface 18 of the shoe with an arched cross section and the generally flat surface at the top 19 of the valve stem 20 produces high contact stresses, but low frictional wear.
[0043] Another advantageous feature of the invention consists of the possibility of implementing a simple but effective system for lubricating the roller, based on the use of the oil which is supplied from the hydraulic tappet and which has the function of lubricating the surfaces 15 and 16 of contact between the tappet 3 and the rocker arm 2 . With reference to FIG. 5, a through-hole 43 of small diameter is formed at the top of the ogive-shaped surface 15 of the insert, the hole 43 allowing the lubricating oil to flow from the zone of engagement with the top end of the tappet towards the upper surface of the insert around the lug 29 . The oil may thus be collected in an impression 44 (FIG. 4) formed in the bottom wall of the horizontal plate portion 11 of the rocker arm around the hole 45 and distributed towards the roller by means of a channel 46 . The channel 46 is also formed on the bottom wall of the plate portion 11 so as to perform lubrication of the contact surfaces of the roller 8 and the cam member 4 . In addition to the channel 46 which can be seen in FIG. 4, arranged longitudinally, other channels may also be formed, for example two channels arranged laterally on opposite sides of the above-mentioned channel 46 so as to convey part of the oil collected in the impression 44 towards the two zones of frictional contact between the side surfaces of the roller and the inner faces of the side walls 12 and 13 of the rocker arm body.
[0044] Obviously, without modifying the principle of the invention, the embodiments and the constructional details may be greatly varied from that described and illustrated purely by way of a non-limiting example, without thereby departing from the scope of the invention as defined in the accompanying claims.
[0045] The invention has been described in great detail in the foregoing specification, and it is believed that various alterations and modifications of the invention will become apparent to those skilled in the art from a reading and understanding of the specification. It is intended that all such alterations and modifications are included in the invention, insofar as they come within the scope of the appended claims. | The rocker arm ( 2 ), obtained from a shaped element ( 30 ) made of metallic material, comprises surfaces ( 15,18 ) for engagement with a tappet ( 3 ) and with a stem ( 20 ) of a valve, respectively, and a portion ( 7 ) for mounting of a rotatable roller ( 8 ) able to co-operate with a cam-type actuating member ( 4 ). According to the invention, the surface ( 15 ) is formed in an insert ( 25 ) produced separately and fixed to the rocker arm. This constructional solution is particularly advantageous when the design constraints, determined by the position of the other elements of the valve train, require a substantial alignment between the center (A) of the surface ( 15 ) engaging the tappet, the center (B) of the roller and the contact (C) surface engaging the valve stem ( 20 ). | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a continuation of U.S. application Ser. No. 13/856,880, filed Apr. 4, 2013, which is a continuation of Ser. No. 12/986,998, filed on Jan. 7, 2011, now U.S. Pat. No. 8,426,716, issued on Apr. 13, 2013, both of which are herein incorporated by reference in their entirety for all purposes.
FIELD
The disclosed technology relates generally to devices and methods for playing a virtual musical instrument such as a virtual keyboard.
BACKGROUND
Virtual musical instruments, such as MIDI-based or software-based keyboards, guitars, strings or horn ensembles and the like typically have user interfaces that simulate the actual instrument. For example, a virtual piano or organ will have an interface configured as a touch-sensitive representation of a keyboard; a virtual guitar will have an interface configured as a touch-sensitive fretboard. Such interfaces assume the user is a musician or understands how to play notes, chords, chord progressions etc., on a real musical instrument corresponding to the virtual musical instrument, such that the user is able to produce pleasing melodic or harmonic sounds from the virtual instrument. Such requirements create many problems.
First, not all users who would enjoy playing a virtual instrument are musicians who know how to form chords or construct pleasing chord progressions within a musical key. Second, users who do know how to form piano chords may find it difficult to play the chords on the user interfaces, because the interfaces lack tactile stimulus, which guides the user's hands on a real piano. For example, on a real piano a user can feel the cracks between the keys and the varying height of the keys, but on an electronic system, no such textures exist. These problems lead to frustration and make the systems less useful, less enjoyable, and less popular. Therefore, a need exists for a system that strikes a balance between simulating a traditional musical instrument and providing an optimized user interface that allows effective musical input and performance, and that allows even non-musicians to experience a musical performance on a virtual instrument.
SUMMARY
Various embodiments provide systems, methods, and devices for musical performance and/or musical input that solve or mitigate many of the problems of prior art systems. A user interface presents a number of chord touch regions, each corresponding to a chord of a diatonic key, such as a major or minor key. The chord touch regions are arranged in a predetermined sequence, such as by fifths within a particular key. Within each chord region a number of touch zones are provided, including treble clef zones and bass clef zones. Each treble clef touch zone within a region will sound a different chord voicing (e.g., root position, first inversion, second inversion, etc.) when selected by a user. Each bass clef touch zone will sound a bass note of the chord. Other user interactions can modify or mute the chords, and vary the bass notes being played together with the chords. A set of related chords and/or a set of rhythmic patterns can be generated based on a selected instrument and a selected style of music. Such a user interface allows a non-musician user to instantly play varying chords and chord voicings within a particular musical key, such that a pleasing musical sound can be obtained even without knowledge of music theory.
BRIEF DESCRIPTION OF THE DRAWINGS
In order to further explain describe various aspects, examples, and inventive embodiments, the following figures are provided.
FIG. 1 depicts a schematic illustration of a user interface according to one aspect of the disclosed technology.
FIGS. 2A-2F depict schematic illustrations of a possible playing sequence by a user in accordance with an aspect of the disclosed technology.
FIG. 3 depicts a schematic illustration of an auto-play mode of the user interface in accordance with another aspect of the disclosed technology.
It should be understood that the various embodiments are not limited to the arrangements and instrumentality shown in the drawings.
DETAILED DESCRIPTION
The functions described as being performed by various components can be performed by other components, and the various components can be combined and/or separated. Other modifications can also be made.
All numeric values are herein assumed to be modified by the term “about,” whether or not explicitly indicated. The term “about” generally refers to a range of numbers that one of skill in the art would consider equivalent to the recited value (i.e., having the same function or result). In many instances, the term “about” may include numbers that are rounded to the nearest significant figure. Numerical ranges include all values within the range. For example, a range of from 1 to 10 supports, discloses, and includes the range of from 5 to 9. Similarly, a range of at least 10 supports, discloses, and includes the range of at least 15.
The following disclosure describes systems, methods, and products for musical performance and/or input. Various embodiments can include or communicatively couple with a wireless touchscreen device. A wireless touchscreen device including a processor can implement the methods of various embodiments. Many other examples and other characteristics will become apparent from the following description.
A musical performance system can accept user inputs and audibly sound one or more tones. User inputs can be accepted via a user interface. A musical performance system, therefore, bears similarities to a musical instrument. However, unlike most musical instruments, a musical performance system is not limited to one set of tones. For example, a classical guitar or a classical piano can sound only one set of tones, because a musician's interaction with the physical characteristics of the instrument produces the tones. On the other hand, a musical performance system can allow a user to modify one or more tones in a set of tones or to switch between multiple sets of tones. A musical performance system can allow a user to modify one or more tones in a set of tones by employing one or more effects units. A musical performance system can allow a user to switch between multiple sets of tones. Each set of tones can be associated with a channel strip (CST) file.
A CST file can be associated with a particular track. A CST file can contain one or more effects plugins, one or more settings, and/or one or more instrument plugins. The CST file can include a variety of effects. Types of effects include: reverb, delay, distortion, compressors, pitch-shifting, phaser, modulations, envelope filters, equalizers. Each effect can include various settings. Some embodiments provide a mechanism for mapping two stompbox bypass controls in the channel strip (.cst) file to the interface. Stompbox bypass controls will be described in greater detail hereinafter. The CST file can include a variety of settings. For example, the settings can include volume and pan. The CST file can include a variety of instrument plugins. An instrument plugin can generate one or more sounds. For example, an instrument plugin can be a sampler, providing recordings of any number of musical instruments, such as recordings of a guitar, a piano, and/or a tuba. Therefore, the CST file can be a data object capable of generating one or more effects and/or one or more sounds. The CST file can include a sound generator, an effects generator, and/or one or more settings.
A musical performance method can include accepting user inputs via a user interface, audibly sounding one or more tones, accepting a user request to modify one or more tones in a set of tones, and/or accepting a user request to switch between multiple sets of tones.
A musical performance product can include a computer-readable medium and a computer-readable code stored on the computer-readable medium for causing a computer to perform a method that includes accepting user inputs, audibly sounding one or more tones, accepting a user request to modify one or more tones in a set of tones, and/or accepting a user request to switch between multiple sets of tones.
A non-transitory computer readable medium for musical performance can include a computer-readable code stored thereon for causing a computer to perform a method that includes accepting user inputs, audibly sounding one or more tones, accepting a user request to modify one or more tones in a set of tones, and/or accepting a user request to switch between multiple sets of tones.
A musical input system can accept user inputs and translate the inputs into a form that can be stored, recorded, or otherwise saved. User inputs can include elements of a performance and/or selections on one or more effects units. A performance can include the playing of one or more notes simultaneously or in sequence. A performance can also include the duration of one or more played notes, the timing between a plurality of played notes, changes in the volume of one or more played notes, and/or changes in the pitch of one or more played notes, such as bending or sliding.
A musical input system can include or can communicatively couple with a recording system, a playback system, and/or an editing system. A recording system can store, record, or otherwise save user inputs. A playback system can play, read, translate, or decode live user inputs and/or stored, recorded, or saved user inputs. When the playback system audibly sounds one or more live user inputs, it functions effectively as a musical performance device, as previously described. A playback system can communicate with one or more audio output devices, such as speakers, to sound a live or saved input from the musical input system. An editing system can manipulate, rearrange, enhance, or otherwise edit the stored, recorded, or saved inputs.
Again, the recording system, the playback system, and/or the editing system can be separate from or incorporated into the musical input system. For example, a musical input device can include electronic components and/or software as the playback system and/or the editing system. A musical input device can also communicatively couple to an external playback system and/or editing system, for example, a personal computer equipped with playback and/or editing software. Communicative coupling can occur wirelessly or via a wire, such as a USB cable.
A musical input method can include accepting user inputs, translating user inputs into a form that can be stored, recorded, or otherwise saved, storing, recording, or otherwise saving user inputs, playing, reading, translating, or decoding accepted user inputs and/or stored, recorded, or saved user inputs, and manipulating, rearranging, enhancing, or otherwise editing stored, recorded, or saved inputs.
A musical input product can include a computer-readable medium and a computer-readable code stored on the computer-readable medium for causing a computer to perform a method that includes accepting user inputs, translating user inputs into a form that can be stored, recorded, or otherwise saved, storing, recording, or otherwise saving user inputs, playing, reading, translating, or decoding accepted user inputs and/or stored, recorded, or saved user inputs, and manipulating, rearranging, enhancing, or otherwise editing stored, recorded, or saved inputs.
A non-transitory computer readable medium for musical input can include a computer-readable code stored thereon for causing a computer to perform a method that includes accepting user inputs, translating user inputs into a form that can be stored, recorded, or otherwise saved, storing, recording, or otherwise saving user inputs, playing, reading, translating, or decoding accepted user inputs and/or stored, recorded, or saved user inputs, and manipulating, rearranging, enhancing, or otherwise editing stored, recorded, or saved inputs.
Accepting user inputs is important for musical performance and for musical input. User inputs can specify which note or notes the user desires to perform or to input. User inputs can also determine the configuration of one or more features relevant to musical performance and/or musical input. User inputs can be accepted by one or more user interface configurations.
Musical performance system embodiments and/or musical input system embodiments can accept user inputs. Systems can provide one or more user interface configurations to accept one or more user inputs.
Musical performance method embodiments and/or musical input method embodiments can include accepting user inputs. Methods can include providing one or more user interface configurations to accept one or more user inputs.
Musical performance product embodiments and/or musical input product embodiments can include a computer-readable medium and a computer-readable code stored on the computer-readable medium for causing a computer to perform a method that includes accepting user inputs. The method can also include providing one or more user interface configurations to accept one or more user inputs.
A non-transitory computer readable medium for musical performance and/or musical input can include a computer-readable code stored thereon for causing a computer to perform a method that includes accepting user inputs. The method can also include providing one or more user interface configurations to accept one or more user inputs.
The one or more user interface configurations, described with regard to system, method, product, and non-transitory computer-readable medium embodiments, can include a chord view and a notes view.
FIG. 1 shows a schematic illustration of an intelligent user interface 100 for a virtual musical instrument. FIG. 1 shows the user interface displayed on a tablet computer such as the Apple iPad®; however the interface could be used on any touchscreen or touch-sensitive computing device. The interface 100 includes a rig or sound browser button 180 , which is used to select the virtual instrument (e.g., acoustic piano, electric piano, electronic organ, pipe organ, etc.) desired by the user. When a user selects an instrument with the rig browser 180 , the system will load the appropriate CST file for that instrument.
The interface 100 includes a number of chord touch regions 110 , shown for example as a set of eight adjacent columns or strips. Each touch region corresponds to a pre-defined chord within one or particular keys, with adjacent regions configured to correspond to different chords and progressions within the key or keys. For example, the key of C major includes the chords of C major (I), D minor (ii), E minor (iii), F major (IV), G major (V), A minor (vi), and B diminished (vii), otherwise known as the Tonic, Supertonic, Mediant, Subdominant, Dominant, Submediant, and Leading Tone. In the example shown in FIG. 1 , an additional chord of B-flat major is included for the key of C major. In the example shown in FIG. 1 , the chords are arranged sequentially according to the circle of fifths. This arrangement allows a user to create sonically pleasing sequences by exploring adjacent touch regions.
Each chord touch region is divided into a number of touch zones 160 and 170 . Zones 160 correspond to various chord voicings of the same chord in the treble clef (right hand), and zones 170 correspond to different bass note chord elements in the bass clef (left hand). In the example shown in FIG. 1 , there are five zones 160 for the treble clef and three zones 170 for the bass clef. Each touch zone 160 in the treble clef corresponds to a different voicing of the same chord of the region 110 . For example, the lowermost zone 160 of the C major region could correspond to the root position of the C major chord, or the triad notes C-E-G played with the C note being the lowest tone in the triad. The adjacent zone 160 could correspond to the first inversion of the C major chord, or the notes E-G-C with the E note being the lowest tone; the next higher zone 160 could correspond to the second inversion of the C major chord, or the notes G-C-E with the G note being the lowest tone, etc. Swiping up or down through the zones 160 causes the chord voicing to change by the minimum number of notes needed to switch to the nearest inversion from the chord voicing that was being played prior to the finger swipe motion.
The lower three zones 170 correspond to bass clef voicings, and may be for example root-five-octave sets, or root notes in different octaves. For example, the lower three zones 170 in the C major region could correspond to the notes C-G-C respectively, or the notes C-C-C in different octaves.
The chords and bass notes assigned to each touch zone 160 , 170 can be small MIDI files. MIDI (Musical Instrument Digital Interface) is an industry-standard protocol defined in 1982 that enables electronic musical instruments such as keyboard controllers, computers, and other electronic equipment to communicate, control, and synchronize with each other. Touching any zone 160 in a region 110 plays the chord MIDI file assigned to that zone, while touching any zone 170 in a region 110 plays the bass note MIDI file assigned that zone. Only one touch zone can be active for a treble clef zone and only one touch zone can be active for a bass clef zone at any time.
The interface 110 also includes various auto-play/effects knobs. A groove knob 120 is used to select one of a number of predefined tempo-locked rhythms that will loop a MIDI file. When the user selects one of the auto-play options of the groove knob, the assigned rhythm will play for the corresponding chord of the zone 160 when it is first touched by the user. The groove rhythm will latch, meaning that the rhythm will stop when the user touches the same chord zone again. The groove rhythm will switch to a new chord when a different chord is selected by the user touching another zone. Each auto-play groove will include a treble (right hand) and bass (left hand) part. A touch zone at the top of the chord regions or strips 110 where the name of the chord is displayed will trigger the playing of default treble and bass parts for the selected chord. Touching a treble zone will trigger only the treble part of the groove rhythm and similarly touching a bass zone will trigger only the bass part of the groove rhythm. Additionally, effects such as tremolo and chorus may be turned on or off by the user selecting positions of tremolo and chorus knobs 140 and 150 . Sustain knob 130 simulates a sustain pedal on an instrument. Notes for the chord player will sustain as long as a zone is being touched, just like a standard MIDI keyboard unless they are modified with the sustain pedal. When on, the sustain command will remain active until the chord being played is changed. So long as user input is within the same region, the sustain effect will remain locked on. When the chord is changed, the sustain effect will be cleared, and then restarted.
FIGS. 2A-2F illustrate examples of possible sequences of user actions on the intelligent interface. A user could play a lower region zone from one chord while playing an upper region zone from another chord, effectively allowing diatonic slash chords to be played. A user could also play upper regions from different chords at the same time, effectively building diatonic poly-chords. For instance, playing an A minor chord with a C Major chord will yield an A minor 7 th chord. Or, playing a G Major chord with a B diminished chord will create a G Major 7 th chord.
As shown in FIG. 2A , when a user taps or touches a top zone 211 in the C Major region, the upper (treble clef) and lower (bass clef) parts of the selected groove rhythm are played. In FIG. 2B , the user then touches or taps top zone 212 in the G Major region. This causes the selected groove rhythm to switch to the G Major chord. Next, as shown in FIG. 2C , the user taps or touches the lower (bass clef) zone 213 in the C Major region. This causes the selected groove rhythm to switch to the bass clef part of the C Major region, while continuing to play the groove rhythm of the upper (treble clef) G Major chord.
Next in the exemplary sequence of play, as shown in FIG. 2D , the user would tap or touch upper (treble clef) zone 214 in the G Major region. This would cause the treble G Major groove rhythm to stop playing, while the lower (bass clef) C Major groove rhythm would continue to play. In FIG. 2E , the user touches or taps the lower (bass clef) zone 215 in the Bb Major region. This causes the lower (bass clef) groove rhythm to switch to the Bb Major notes, while the upper (treble clef) would remain off. Finally, in FIG. 2F the user touches or taps the top zone 216 in the F Major region. This causes the upper (treble clef) and lower (bass clef) groove rhythms to play using the G Major triad notes and bass notes associated with the G Major region.
FIG. 3 illustrates an auto-play mode of the intelligent interface. When the groove knob is set to a state other than “off,” the zone divider lines of the upper and lower touch zones in each region will become faded, indicating that the individual touch zones are inactive. Instead, the chord regions will have three touch positions: a Top/Lock zone position 311 , an Upper/Treble zone position 312 , and a Lower/Bass zone position 313 .
When a user taps or touches the Top/Lock position 311 , the selected groove rhythm will be started for both the upper (treble clef) and lower (bass clef) parts in the selected chord. If the same position 311 is touched again, the upper and lower groove rhythms will be stopped.
If a user taps or touches a Lower/Bass zone position 313 within a chord region, the groove rhythm of the lower (bass clef) part will switch to that chord independently of the chord playing in the upper (treble clef) part. Similarly, if a user taps or touches an Upper/Treble zone position 312 within a chord region, the groove rhythm of the upper (treble clef) part will switch to that chord independently of the chord playing in the lower (bass clef) part. If a user taps or touches the Top/Lock position 311 when different upper and lower groove rhythm regions are playing, then both the upper and lower parts will switch to the new chord region.
As stated above, swiping vertically within a chord region will cause the chords in the different zones to be played without requiring a new tap. Common tones between the different chord inversions will not be re-triggered when approached by a swipe, but only new non-common tones will be triggered by the swipe, while common tones will continue to play. Moving in a horizontal swipe motion after a chord has been triggered will cause an effect to be triggered. Examples could be Mod Wheel effects, wah-wah, etc. The intelligent interface also will respond to velocity via the accelerometer.
Touching a zone with two fingers will play an alternate version of the groove MIDI file. If two fingers touch inside any of the zones in a chord region an alternate version of the groove is played. Typically this would involve harmonic changes to the groove, for instance changing to a suspended version of the chord or adding extensions (i.e., sixths, sevenths, ninths etc.). When the second touch is added to a single touch of the chord, the groove will switch to the alternate version. When the second touch is removed from the region but one touch remains active, the groove will switch back to the standard version of the groove. If both fingers are removed simultaneously or within a small time delta of each other, the alternate version of the groove will latch.
When switching to a new chord, a two finger tap will be required to trigger the alternate version of the groove for the new chord. In other words, if the user triggered the alternate groove with a two finger tap on the Top/Lock zone for C Major, then moved to F Major with a single finger tap on the Top/Lock zone for F Major, the F Major groove would be the standard F groove, not the alternate groove, until a two finger touch was detected. Two finger touches must occur within the same chord region to trigger an alternate groove.
The above disclosure provides examples and aspects relating to various embodiments within the scope of claims, appended hereto or later added in accordance with applicable law. However, these examples are not limiting as to how any disclosed aspect may be implemented, as those of ordinary skill can apply these disclosures to particular situations in a variety of ways.
All the features disclosed in this specification (including any accompanying claims, abstract, and drawings) can be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.
Any element in a claim that does not explicitly state “means for” performing a specified function, or “step for” performing a specific function, is not to be interpreted as a “means” or “step” clause as specified in 35 U.S.C §112, sixth paragraph. In particular, the use of “step of” in the claims herein is not intended to invoke the provisions of 35 U.S.C §112, sixth paragraph. | A user interface for a virtual musical instrument presents a number of chord touch regions, each corresponding to a chord of a diatonic key. Within each chord region a number of touch zones are provided, including treble clef zones and bass clef zones. Each treble clef touch zone within a region will sound a different chord voicing. Each bass clef touch zone will sound a bass note of the chord. Other user interactions can modify or mute the chords, and vary the bass notes being played together with the chords. A set of related chords and/or a set of rhythmic patterns can be generated based on a selected instrument and a selected style of music. | 6 |
CROSS REFERENCE TO RELATED APPLICATION
This divisional application claims priority from U.S. application Ser. No. 09/351,882, filed Jul. 13, 1999, now allowed, which claims the benefit of U.S. Provisional Application No. 60/097,008, filed Aug. 18, 1998.
BACKGROUND OF THE INVENTION
The present invention relates to resist materials for use in lithography, for example, in the production of integrated circuits and particularly to polymers having acetal or ketal functional groups containing silicon.
It is well known in the art to produce positive photoresist formulations such as those described in U.S. Pat. Nos. 3,666,473; 4,115,128; and 4,173,470. These include alkali-soluble phenol-formaldehyde novolac resins together with light-sensitive materials, usually a substituted diazonaphthoquinone compound. The resins and sensitizers are dissolved in an organic solvent or mixture of solvents and are applied as a thin film or coating to a substrate suitable for the particular application desired.
The resin component of these photoresist formulations is soluble in aqueous alkaline solutions, but the naphthoquinone compound acts as a dissolution rate inhibitor with respect to the resin. Upon exposure of selected areas of the coated substrate to actinic radiation, however, the naphthoquinone compound undergoes a radiation induced structural transformation, and the exposed areas of the coating are rendered more soluble than the unexposed areas. This difference in solubility rates causes the exposed areas of the photoresist coating to be dissolved when the substrate is immersed in an alkaline developing solution while the unexposed areas are largely unaffected, thus producing a positive relief pattern on the substrate.
An alternative method for forming the pattern in a resist is referred to as chemical amplification. This method is described by C. G. Willson in Introduction to Microlithography (American Chemical Society, 1994, pp. 212-231). In this method, a photoacid generator is added to a polymer containing acid-labile groups. When a coating of this mixture is exposed to actinic radiation in an imagewise fashion, the photoacid generator in those areas struck by light will produce acid, and this acid causes a reaction of the acid-labile groups in the polymer. The polymer that has reacted in this manner is rendered soluble in aqueous base, and the image can be developed in the same manner as described above. Chemically amplified resist systems typically require a much lower dose of actinic radiation to effectively develop the pattern than do the novolac/diazoquinone type resist systems.
In most instances, the exposed and developed photoresist on the substrate will be subjected to treatment by a substrate-etchant solution or gas. The photoresist coating protects the coated areas of the substrate from the etchant, and thus the etchant is only able to etch the uncoated areas of the substrate, which in the case of a positive photoresist, correspond to the areas that were exposed to actinic radiation. Thus, an etched pattern can be created on the substrate which corresponds to the pattern on the mask, stencil, template, etc., that was used to create selective exposure patterns on the coated substrate prior to development.
The relief pattern of the photoresist on the substrate produced by the method described above is useful for various applications including as an exposure mask or a pattern such as is employed in the manufacture of miniaturized integrated electronic components.
The properties of a photoresist composition which are important in commercial practice include the photospeed of the resist, development contrast, resist resolution, and resist adhesion.
Resist resolution refers to the capacity of a resist system to reproduce the smallest features from the mask to the resist image on the substrate.
In many industrial applications, particularly in the manufacture of miniaturized electronic components, a photoresist is required to provide a high degree of resolution for very small features (on the order of two microns or less).
The ability of a resist to reproduce very small dimensions, on the order of a micron or less, is extremely important in the production of large-scale integrated circuits on silicon chips and similar components. Circuit density on such a chip can only be increased, assuming photolithography techniques are utilized, by increasing the resolution capabilities of the resist.
Photoresists are generally categorized as being either positive working or negative working. In a negative working resist composition, the imagewise light-struck areas harden and form the image areas of the resist after removal of the unexposed areas with a developer. In a positive working resist composition, the exposed areas are the non-image areas. The light-struck parts are rendered soluble in aqueous alkali developers. While negative resists are the most widely used for industrial production of printed circuit boards, positive resists are capable of much finer resolution and smaller imaging geometries. Hence, positive resists are the choice for the manufacture of densely packed integrated circuits.
In the normal manner of using a positive photoresist, a single layer of this material is imaged to give a mask on the substrate, which can further be etched with a suitable etchant or used for deposition of materials, such as metals. However, due to the limitations of optical imaging systems, resolution of small patterns, on the order of 2 microns or less, is limited, particularly if topography is present on the substrate. It was discovered by B. J. Lin and T. H. P. Chang, J. Vac. Sci. Tech. 1979, 16, p. 1669, that this resolution can be further improved by using multilevel systems to form a portable conformable mask.
In a conventional two-layer resist system (B. J. Lin, Solid State Technol., 1983, 26 (5), p. 105), the substrate is first coated with a relatively thick planarizing layer to level any topography that might be present on the substrate. A relatively thin imaging layer resist is next coated on top of the planarizing layer. A latent image is deposited in the imaging layer by irradiation of this layer through a mask, and the desired pattern is formed in the imaging layer by subsequent development using conventional means. Pattern transfer to the substrate from the imaging layer through the underlying planarizing layer is finally accomplished by an anisotropic oxygen plasma etch (O 2 RIE). Hence much importance is given to the resistance of the imaging layer resist to O 2 RIE. Generally, those materials that form oxides upon O 2 RIE, for example those containing >10% by weight silicon, are considered to have high resistance to O 2 RIE.
SUMMARY OF THE INVENTION
The polymers of the present invention are characterized by having at least one pendent acetal or ketal functional group in which at least two substituents of the acetal/ketal carbon atom independently comprise at least one silicon atom. The compositions of the present invention are useful as positive working resist compositions, in particular as the top imaging layer in a bilayer resist scheme for use in the manufacture of integrated circuits. The incorporation of at least two silicon atoms in each monomeric unit enables the formation of a robust etch mask upon exposure to an oxygen plasma used in reactive ion etching processes.
In one aspect, the present invention provides a polymer comprising a polymeric backbone having at least one pendent acetal/ketal functional group having an acetal/ketal carbon atom in which at least two substituents attached to the acetal/ketal carbon atom independently comprise at least one silicon atom.
In another aspect, the present invention provides a resist material comprising compounds having the formula:
wherein
R is a divalent connecting group or a covalent bond;
R 1 is alkyl, aryl, aralkyl, or silyl;
R 2 is a hydrogen atom, alkyl, aryl, aralkyl, or silyl;
R 3 is alkyl, aryl, aralkyl, or silyl;
or any two of R 1 , R 2 , or R 3 may be combined to form a cyclic group, with the proviso that at least two of R 1 , R 2 , or R 3 comprise at least one silicon atom and wherein n is an integer greater than or equal to 1.
In another aspect, the present invention provides a method of forming resist patterns comprising the steps of:
a) providing a polymer comprising a polymeric backbone having at least one pendent acetal/ketal functional group having an acetal/ketal carbon atom in which at least two substituents attached to the acetal/ketal carbon atom independently comprise at least one silicon atom;
b) providing a substrate having an organic polymer base layer;
c) coating the silicon-containing polymer onto the organic polymer base layer of the substrate to form a top layer;
d) exposing the coated substrate to actinic radiation sufficient to form a latent image; and
e) developing the latent image.
In this application, “an acetal/ketal functional group” is represented by the formula: —O—C(OR 1 )(R 2 )(R 3 ); an “acetal/ketal carbon atom” is a carbon atom that is bound to both oxygen atoms in the acetal/ketal functional group; the acetal/ketal carbon atom is an acetal carbon atom if R 2 is a hydrogen atom; if each of R 2 and R 3 is an alkyl or an aryl group, the carbon atom is a ketal carbon atom; and a “substituent” is any group or covalent bond represented by R, R 1 , R 2 , and R 3 . It is to be understood that the terms “alkyl”, “aryl”, and “aralkyl groups” and the like include such groups that are substituted with other groups including but not limited to —Si— or —Si—O— containing groups.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows cross-sectional views illustrating a process of forming resist patterns according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The backbone of the polymers of the invention may be any polymeric chain of monomers capable of being developed provided that the backbone chemistry allows for the polymers of the invention, that is, polymers with a least one of the above-described pendent groups having an acetal/ketal carbon atom in which at least two substituents attached to the acetal/ketal carbon atom independently comprise at least one silicon atom.
Suitable backbones for the polymers of the invention include homopolymers and copolymers comprising monomers such as vinylphenols, (meth)acrylic acids, alkyl (meth)acrylates, maleic anhydrides, vinylbenzoic acids, alkyl vinylbenzoates, and alpha-olefins such as ethylene, propylene, and the like.
Preferred homo- and co-polymers for use as backbones of the polymers of the invention include poly(4-vinylphenol), poly(vinylbenzoic acid), methyl methacrylate-co-methacrylic acid, and methacrylic acid-co-4-vinylphenol.
Useful divalent connecting groups represented by R include branched or unbranched and/or substituted or unsubstituted groups including —CH 2 — n wherein n is an integer from 1 to 18, arylene, arylenecarbonyl, carbonyl, cyclohexylene, aralkylene, and the like. Preferred R substituents are arylene, arylenecarbonyl, and carbonyl.
Useful substituents represented by R 1 include branched or unbranched and substituted or unsubstituted groups including alkyl, preferably C 1 -C 8 , aryl, aralkyl, silyl, trialkylsilyl, pentaalkyldisilyl, and the like. Any of the R 1 substituents may contain at least one silicon atom. Preferred R 1 substituents are trialkylsilyl and pentaalkyldisilyl. More preferred R 1 substituents are trimethylsilyl, tert-butyldimethylsilyl, and pentamethyldisilyl.
Useful substituents represented by R 2 include hydrogen and branched or unbranched and substituted or unsubstituted groups including alkyl, preferably C 1 -C 8 , aryl, aralkyl, silyl, trialkylsilyl, pentaalkyldisilyl, (trialkylsiloxy)silyl, and the like. Any of the R 2 substituents may contain at least one silicon atom. Preferred R 2 substituents are hydrogen and alkyl. More preferred R 2 substituents are hydrogen, methyl, 3-(trimethylsilyl)propyl, 3,3,3-tris(trimethylsilyl)propyl, tris(trimethylsilyl)silylethyl, and tris(trimethylsilyloxy)silylethyl.
Useful substituents represented by R 3 include branched or unbranched and substituted or unsubstituted groups including alkyl, preferably C 1 -C 8 , aryl, aralkyl, silyl, trialkylsilyl, pentaalkyldisilyl, and the like. Any of the R 3 substituents may contain at least one silicon atom. A preferred R 3 substituent is alkyl. More preferred R 3 substituents are 3-(trimethylsilyl)propyl, 3,3,3-tris(trimethylsilyl)propyl, tris(trimethylsilyl)silylethyl, and tris(trimethylsilyloxy)silylethyl.
Additionally, any two of R 1 , R 2 , and R 3 may be combined to form a cyclic group containing, in addition to carbon atoms, oxygen, silicon, and/or sulfur. An example of such a group is the tetrahydropyran-2-yl group.
A preferred polymer of the invention is represented by the following formula:
wherein preferably the sum of x+y is a number, preferably, an integer ranging from about 5 to about 1000, x is a number, preferably, an integer ranging from 0 to about 950 and y is number, preferably, an integer ranging from 1 to about 1000.
Another preferred polymer of the invention is represented by the following formula:
wherein preferably the sum of x+y is a number, preferably, an integer ranging from about 5 to about 1000, x is a number, preferably, an integer ranging from 0 to about 950 and y is a number, preferably, an integer ranging from 1 to about 1000.
Useful acid generators of the invention are compounds or compositions, which produce acid on exposure to actinic radiation. Examples of useful acid generators include those described by T. Ueno in Microlithography Science and Technology, Marcel Decker, pp. 429-464 (1998), incorporated herein by reference. Preferred acid generators are onium salts such as diaryliodonium salts and triarylsulfonium salts as described in Microlithography Science and Technology, cited above. More preferred acid generators are diaryl iodonium salts such as tolylcumyliodonium tetrakis(pentafluorophenyl)borate, diphenyliodonium trifluoromethanesulfonate, bis(4-tolyl)iodonium trifluoromethanesulfonate, and bis(4-tolyl)iodonium perfluorobutanesulfonate.
The silicon-containing acetal polymers of the invention are generally made by the addition of a phenolic or carboxylic acid group to a silicon-containing enolether.
FIG. 1 shows cross-sectional views illustrating the process of forming resist patterns according to the present invention. First, a thin film of an organic polymer 2 (any suitable and etchable organic polymer film used in the art) is applied to a substrate 1 such as a silicon wafer (primed or unprimed) (step A: coating of a base polymer layer). A thin film of the resist composition of the invention 3 is applied to the organic polymer film 2 completing a two-layer structure on the substrate (step B: coating of a top layer). The coated substrate is optionally prebaked (step C: prebaking), the top layer is subsequently masked, and the two layered structure is irradiated through the mask so to release acid from the acid generator contained in the resist composition (step D: imagewise exposure). The coated and exposed wafer is optionally heated to speed the acid-catalyzed cleavage of the acetal or ketal functionalized groups of the polymer of the invention (step E: post exposure baking (also referred to as PEB)). As a result, the masked portion of the resist remains insoluble in an aqueous alkali solution. Thereafter, the exposed resist material in the unmasked region is removed with an alkali developer (step F: development). The patterned two layered structure is then dry-etched using, for example, an oxygen plasma such that the lower organic polymer film 2 is removed from those areas from which the top layer resist composition of the invention has been removed (step G: dry etching), thus forming a resist pattern. Suitable organic polymers for the base organic layer include any organic polymer material that can be etched with oxygen plasma. The radiation used to form the image in the resist can be of any wavelength that results in release of acid from the acid generator.
EXAMPLES
Preparation of 2,2,3,3,9,9-hexamethyl-4-oxa-3,9-disiladec-5-ene
A dried reaction flask equipped for magnetic stirring was flushed with nitrogen and charged with a 1 F solution of (trimethylsilylmethyl)magnesium chloride in diethyl ether (300 ml, 300 mmol). Diethyl ether was distilled under reduced pressure. The resulting neat Grignard reagent was dissolved in 500 mL of dry tetrahydrofuran, the solution was cooled to −78 ° C., and copper(I) bromide-dimethyl sulfide complex (2.16 grams, 10.5 mmol, available from Aldrich Chemical Company, Inc., Milwaukee, Wis.) and hexamethylphosphoramide (100 grams, 560 mmol, available from Aldrich Chemical Company, Inc.) were added to the reactor with stirring. Acrolein (14.1 mL, 11.8 grams, 210 mmol, available from Aldrich Chemical Company, Inc.) dissolved in a 1 M solution of tert-butyldimethylsilyl chloride (300 mL, 300 mmol, available from Aldrich Chemical Company, Inc.) in tetrahydrofuran was added dropwise to the cooled reaction mixture, with stirring, over a period of 3 hours. After an additional 2 hours reaction time, triethylamine (42.0 mL, 30.5 grams, 300 mmol, available from Aldrich Chemical Company, Inc.) was added, and the reaction mixture was subsequently allowed to warm to room temperature. The reaction mixture was diluted with pentane (1 L), water (50 mL) was added, and the mixture was transferred to a separatory funnel. The organic phase was separated from the aqueous phase and washed with water (ten×50-mL portions) to remove hexamethylphosphoramide. The combined aqueous washes were extracted once with pentane (100 mL), and the combined organic phases were washed once with a saturated aqueous sodium chloride solution (100 mL) and dried over magnesium sulfate. The mixture was filtered, and the filtrate was concentrated in a rotary evaporator under reduced pressure. Vacuum distillation of the residue afforded 2,2,3,3,9,9-hexamethyl-4-oxa-3,9-disiladec-5-ene as a clear, colorless liquid (49.6 grams, 91 percent). The 1 H, 13 C, and 29 Si NMR spectra of the product were consistent with a 10:1 mixture of the E and Z stereoisomers of 2,2,3,3,9,9-hexamethyl-4-oxa-3,9-disiladec-5-ene.
Preparation of (E)-8,8-bis(trimethylsilyl)-2,2,3,3,9,9-hexamethyl-4-oxa-3,9-disiladec-5-ene
A dried reaction flask equipped for magnetic stirring was flushed with nitrogen and charged with tris(trimethylsilyl)methane (23.3 grams, 100 mmol, available from Aldrich Chemical Company, Inc.) and dry tetrahydrofuran (200 mL). A 1.4 F solution of methyllithium in diethyl ether (86 mL, 120 mmol, available from Aldrich Chemical Company, Inc.) was added, and the reaction mixture was stirred at room temperature for 20 hours. The solution was cooled to −78 ° C., and copper(I) bromide-dimethyl sulfide complex (0.72 gram, 3.5 mmol) and hexamethylphosphoramide (30 grams, 170 mmol) were added to the cooled reaction mixture with stirring. Acrolein (5.3 mL, 4.9 grams, 80 mmole) dissolved in a 1 M solution of tert-butyldimethylsilyl chloride in tetrahydrofuran (100 mL, 100 mmol, available from Aldrich Chemical Company, Inc.), was added to the reaction mixture dropwise, with stirring, over a period of 1 hour. After an additional 2 hours reaction time, triethylamine (14.0 mL, 10.1 grams, 100 mmol) was added, and the reaction mixture was subsequently allowed to warm to room temperature. The reaction mixture was diluted with pentane (300 mL), water (50 mL) was added, and the mixture was transferred to a separatory funnel. The organic phase was separated from the aqueous phase and washed with water (ten×50-mL portions) to remove hexamethylphosphoramide. The combined aqueous washes were extracted once with pentane (100 mL), and the combined organic phases were washed once with a saturated aqueous sodium chloride solution (100 mL) and dried over magnesium sulfate. The mixture was filtered, and the filtrate was concentrated in a rotary evaporator under reduced pressure. Vacuum distillation of the residue afforded (E)-8,8-bis(trimethylsilyl)-2,2,3,3,9,9-hexamethyl-4-oxa-3,9-disiladec-5-ene as a clear, colorless liquid (24.2 grams, 75 percent). The 1 H, 13 C, and 29 Si NMR spectra of the product were consistent with the structure of (E)-8,8-bis(trimethylsilyl)-2,2,3,3,9,9-hexamethyl-4-oxa-3,9-disiladec-5-ene.
Example 1
Preparation of a Copolymer of Formula II
A dried reaction flask equipped for magnetic stirring was flushed with nitrogen and charged with 2,2,3,3,9,9-hexamethyl-4-oxa-3,9-disiladec-5-ene (10.34 grams, 40 mmol, prepared as described above), poly(4-vinylphenol) (4.81 grams, 40 mmol, M n =1500, M w =4000, available from Polysciences Inc., Warrington, Pa.), dichloromethane (70 mL), and tetrahydrofuran (30 mL). p-Toluenesulfonic acid monohydrate (0.15 grams, 0.8 mmol, available from J. T. Baker, Philipsburg, N.J.) was added, and the reaction mixture was stirred at room temperature for 24 hours. Potassium carbonate (11 grams, 80 mmol, available from J. T. Baker) was added, and the reaction mixture was stirred at room temperature for an additional 12 hours. The mixture was filtered, and the filtrate was concentrated under reduced pressure. Methanol (50 mL) was added to the concentrate, and the resultant mixture was stirred vigorously for several minutes. The insoluble phase was separated and washed with methanol (two×20-mL portions). Removal of residual solvent under reduced pressure afforded 4.36 grams of a light yellow solid. Concentration of the methanol extract and similar treatment of the concentrate provided a second crop of 0.93 gram. The 1 H NMR spectrum of the combined product was consistent with a copolymer in which 60-65 percent of the phenolic groups were protected as the corresponding mixed acetal (M n =4000, M w =8500).
Example 2
Preparation of a Copolymer of Formula II
A dried reaction flask equipped for magnetic stirring was flushed with nitrogen and charged with 2,2,3,3,9,9-hexamethyl-4-oxa-3,9-disiladec-5-ene (10.34 grams, 40 mmol, prepared as described above), poly(4-vinylphenol) (7.21 grams, 60 mmol, M n =2000, M w =20,000, available from Polysciences Inc.), dichloromethane (100 mL), and tetrahydrofuran (50 mL). p-Toluenesulfonic acid monohydrate (0.23 grams, 1.2 mmol) was added, and the reaction mixture was stirred at room temperature for 24 hours. Potassium carbonate (14 grams, 100 mmol) was added, and the reaction mixture was stirred at room temperature for an additional 12 hours. The mixture was filtered, and the filtrate was concentrated under reduced pressure. The concentrate was dissolved in tetrahydrofuran (100 mL), and the resulting solution was added dropwise, with rapid stirring, to water (7 L). The precipitated polymer was collected by filtration, washed with water, and dried under vacuum. The product was slurried with pentane and filtered to yield 5.71 grams of a light yellow solid. The 1 H NMR spectrum of the solid was consistent for a copolymer in which 30-35 percent of the phenolic groups were protected as the corresponding mixed acetal (M n =3500, M w =35,000).
Example 3
Preparation of a Copolymer of Formula II
A dried reaction flask equipped for magnetic stirring was flushed with nitrogen and charged with (E)-8,8-bis(trimethylsilyl)-2,2,3,3,9,9-hexamethyl-4-oxa-3,9-disiladec-5-ene (10.12 grams, 25 mmol, prepared as described above), poly(4-vinylphenol) (4.51 grams, 38 mmol, M n =2000, M w =20,000), dichloromethane (70 mL), and tetrahydrofuran (35 mL). p-Toluenesulfonic acid monohydrate (0.14 gram, 0.8 mmol) was added, and the reaction mixture was stirred at room temperature for 24 hours. Potassium carbonate (14 grams, 100 mmol) was added, and the reaction mixture was stirred at room temperature for an additional 12 hours. The mixture was filtered, and the filtrate was concentrated under reduced pressure. The concentrate was dissolved in tetrahydrofuran (100 mL), and the resulting solution was added dropwise, with rapid stirring, to water (7 L). The precipitated polymer was collected by filtration, washed with water, and dried under vacuum. The product was slurried with pentane and filtered to yield 5.33 grams of a light yellow solid. The 1 H NMR spectrum of the product was consistent with a copolymer in which approximately 15 percent of the phenolic groups were protected as the corresponding mixed acetal (M n =3500, M w =35,000).
Example 4
A stock solution was prepared by combining the copolymer of Example 1 (5.26 grams) and propylene glycol methyl ether acetate (21.6 mL). A coating formulation was prepared by combining this solution (3.0 grams) with diphenyliodonium triflate (24 mg, commercially available) and a 0.03 weight percent solution of Dow Corning 5103™ Surfactant (available from Dow Coming Corporation, Midland, Mich.) in ethyl lactate (7.0 grams). The coating formulation was spin coated at 2500 rpm for 60 seconds on a six-inch diameter silicon wafer that had been previously primed with hexamethyldisilazane at 110° C. in a Yield Engineering Systems Model 15 vapor priming oven. The coated wafer was post-apply baked at 85° C. for 60 seconds on a SOLITEC brand hotplate to produce an approximately 1600 angstrom thick coating. The coated wafer prepared in this manner was exposed through a contact mask with a mercury arc lamp (main line at 365 nm) for 35 seconds. The exposed wafer was immersed in 0.21 N aqueous tetramethylammonium hydroxide for 60 seconds and rinsed with water. Examination of the wafer after development revealed that the coating had been completely removed from the areas that had been exposed to actinic radiation while the unexposed regions of the wafer showed no erosion of the applied coating.
Example 5
A stock solution was prepared by combining the copolymer of Example 2 (5.0 grams), tolylcumyliodonium tetrakis(pentafluorophenyl)borate (0.10 grams, available from Rhone-Poulenc North American Chemicals, Rock Hill, S.C.), and propylene glycol methyl ether acetate (20.4 grams). A coating formulation was prepared by combining this solution (4.5 grams) with additional tolylcumyliodonium tetrakis(pentafluorophenyl)borate (25 mg, available from Rhone-Poulenc North American Chemicals). The coating formulation was spin coated at 5500 rpm for 45 seconds on a six-inch diameter silicon wafer bearing a 5000 angstrom thick coating of poly(4-vinylphenol). The coated wafer was post-apply baked on a SOLITEC hotplate at 100° C. for 60 seconds to obtain an approximately 5000 angstrom thick coating. The coated wafer prepared in this manner was pattern exposed on a 248 nm stepper at exposure doses ranging from 1 to 199 mJ/cm 2 in steps of 2 mJ. The exposed wafer was developed with 0.26 N aqueous tetramethylammonium hydroxide for 30 seconds and rinsed with water. Spin coating, post-apply baking, and developing were carried out on an enclosed track system. Examination of the wafer after development revealed 0.475 micron resolved lines and spaces at an exposure dose of 29 mJ/cm 2 .
Example 6
The copolymer of Example 1 (0.48 grams), tolylcumyliodonium tetrakis(pentafluorophenyl)borate (24 mg, available from Rhone-Poulenc North American Chemicals), and propylene glycol methyl ether acetate (1.93 grams) were combined, and the resultant solution was spin coated at 3000 rpm for 60 seconds on a four-inch diameter unprimed silicon wafer. The coated wafer was post-apply baked in a forced air oven at 130° C. for 5 minutes. A thin sheet of aluminum in which several holes had been cut was placed over the coated wafer covering approximately one half of the wafer surface, and the exposed portion of the coating was irradiated by passing the wafer through a UV processor fitted with a FUSION SYSTEMS H bulb (main line at 365 nm, 100 mJ/cm 2 delivered dose). The aluminum sheet was removed and the exposed wafer was immersed in 0.23 N aqueous tetramethylammonium hydroxide for 30 seconds and rinsed with water. Examination of the wafer after development revealed that the coating had been completely removed from the areas that had been exposed to actinic radiation, while the unexposed region of the wafer showed no apparent erosion of the applied coating.
Example 7
The copolymer of Example 3 (0.30 grams), tolylcumyliodonium tetrakis(pentafluorophenyl)borate (60 mg), and propylene glycol methyl ether acetate (1.20 grams) were combined, and the resultant solution was spin coated at 3000 rpm for 60 seconds on a four-inch unprimed silicon wafer. The coated wafer was post-apply baked in a forced air oven at 50° C. for 10 minutes. A thin sheet of aluminum in which several holes had been cut was placed over the coated wafer covering approximately one half of the wafer surface, and the exposed portion of the coating was irradiated by passing the wafer through a UV processor fitted with a FUSION SYSTEMS H bulb (main line at 365 nm, 100 mJ/cm 2 delivered dose). The aluminum sheet was removed, and the exposed wafer was immersed in 0.23 N aqueous tetramethylammonium hydroxide for 2 minutes and rinsed with water. Examination of the wafer after development revealed that the coating had been completely removed from the areas that had been exposed to actinic radiation, while the unexposed region of the wafer showed no apparent erosion of the applied coating.
While the invention has been described in terms of several preferred embodiments in which the resist is applied in a bilayer system, those skilled in the art will recognize that the resist may also be utilized in single or multilayer systems and that the invention can be practiced with further modifications within the spirit and scope of the appended claims. | The polymers of the present invention are characterized by having at least one pendent acetal or ketal functional group in which at least two substituents of the acetal/ketal carbon atom independently comprise at least one silicon atom. The compositions of the present invention are useful as positive working resist compositions, in particular as the top imaging layer in a bilayer resist scheme for use in the manufacture of integrated circuits. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of production of a semiconductor device, more particularly relates to a method of production of a wafer level package.
2. Description of the Related Art
As a method of production of a semiconductor device, there is the method of forming insulating layers, interconnect patterns, external electrode terminals, etc. on the surface of a semiconductor wafer at the stage of the semiconductor wafer where semiconductor chips are formed arranged in predetermined defined arrangements, and finally dicing the semiconductor wafer into individual pieces so as to produce chip-sized semiconductor devices (wafer level package). Japanese Unexamined Patent Publication (Kokai) No. 2002-93942 describes a method of production of a semiconductor device comprising forming a reinterconnect layer at the surface of the semiconductor wafer where the electrode terminals are formed, forming a reinterconnect layer on the back side of a semiconductor chip from the semiconductor chip side, and forming external terminals electrically connected with the electrode terminals.
Japanese Unexamined Patent Publication (Kokai) No. 2002-134651 describes a method of production of a semiconductor device comprising forming connection bumps on electrode terminals of a semiconductor wafer, then covering the surface on which the connection bumps are formed by a resin so that the end faces of the connection bumps are exposed and further covering the back side of the semiconductor wafer by a resin. Further, Japanese Unexamined Patent Publication (Kokai) No. 2002-270720 describes a method of production of a semiconductor device comprising forming projecting electrodes on electrode pads of the surfaces of the semiconductor chips of the semiconductor wafer, covering the surface of the semiconductor wafer by an insulating resin so that the projecting electrodes are exposed, grinding the back side of the semiconductor wafer, then covering the back side of the semiconductor wafer by an insulating resin, and dicing the semiconductor wafer to obtain the individual semiconductor devices.
In the above conventional methods of production of wafer level packages, sputtering etc. are used to form a film on or expose the semiconductor wafer to produce a semiconductor device. Therefore, production of such a product required use of expensive production systems such as film-forming systems or exposure systems. In particular, when using a 300 mm (12 inch) large-sized semiconductor wafer, for which it is considered use will increase, to produce a semiconductor package, it is necessary to construct a new production system, but there is the problem that new investment is necessary.
A wafer level package has a thermal expansion coefficient substantially equal to the thermal expansion coefficient of the silicon material of a semiconductor wafer, so when mounting a wafer level package on a resin board (mounting circuit board) made of a resin usually used for a mounting circuit board, the thermal expansion coefficient greatly differs from the resin board, so there is the problem that heat stress acts on the connecting parts of the wafer level package and resin board (solder balls) and the connecting parts crack. Accordingly, the products previously provided as wafer level packages were limited to small products of a size of not more than 10 mm square or so. Further, in conventional wafer level packages, sometimes the silicon material of the semiconductor wafer was left exposed to the outside in the product. With such a product, the package is insufficiently protected. Further, the back side is not electrically insulated, so electrical short-circuits occur at the back side of the package.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a method of production of a semiconductor device which can be produced without using expensive semiconductor device production systems, can be matched in thermal expansion coefficient with the mounting circuit board, and can be easily mounted.
To attain the above object, there is provided a method of production of a semiconductor device comprising forming vias and other conductor parts on an electrode terminal forming surface of a semiconductor wafer, that are electrically connected with electrode terminals, and dicing the semiconductor wafer into individual semiconductor chips to form chip-sized semiconductor devices, comprising the steps of electrolessly plating the electrode terminals to cover the surfaces of the electrode terminals by a protective film protecting the electrode terminals from laser beams; grinding the back side of the semiconductor wafer to reduce the thickness of the semiconductor wafer before or after forming the protective film; covering the entirety of the electrode terminal forming surface and back side of the semiconductor wafer, having the electrode terminals covered by a protective film and processed to reduce the thickness of the semiconductor wafer, by a resin to form a laminate; and focusing a laser beam toward the electrode terminal forming surface of the semiconductor wafer from outside the laminate to form via holes with the protective film exposed at their bottom surfaces, then filling the via holes by electroplating to form the conductor parts.
Preferably, the method of production further comprises the steps of bonding external connection terminals at lands of the conductor parts after forming the conductor parts and dicing the semiconductor wafer into individual semiconductor chips after bonding the external connection terminals to the lands.
Alternatively, the method of production further comprises, when covering the entirety of the electrode terminal forming surface and back side of the semiconductor wafer by a resin, using a resin having a thermal expansion coefficient close to the thermal expansion coefficient of a resin board. Alternatively, the method of production of a semiconductor device further comprises forming interconnect patterns electrically connected with the conductor parts through the electrical insulating layer after forming the conductor parts.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and features of the present invention will become clearer from the following description of the preferred embodiments given with reference to the attached drawings, wherein:
FIGS. 1A to 1 J is a cross-sectional view of a method of production of a semiconductor device according to the present invention;
FIG. 2 is a cross-sectional view of the configuration of a semiconductor device obtained by dicing a laminate;
FIGS. 3A to 3 E are cross-sectional views of another method of production of a semiconductor device according to the present invention; and
FIGS. 4A to 4 D are cross-sectional views of still another method of production of a semiconductor device according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the present invention will be described in detail below while referring to the attached figures. FIGS. 1A to 1 J and FIG. 2 are cross-sectional views of method of production of a semiconductor device according to a first embodiment of the present invention. FIG. 1A shows a semiconductor wafer 10 having semiconductor chips formed arranged at predetermined defined arrangements. Reference numeral 12 shows electrode terminals (aluminum pads) formed on the electrode forming surface of the semiconductor wafer 10 . Note that at an actual semiconductor wafer, a large number of electrode terminals 12 are formed, but in this figure, the electrode terminals 12 are shown for explanatory purposes.
FIG. 1B shows the state of covering the surfaces of the electrode terminals 12 by a protective film 14 so that the electrode terminals 12 are not damaged by the laser beam used when forming via holes in the insulating layer by laser processing at a later step. The protective film 14 is comprised of a material having conductivity for electrically connecting with the electrode terminals 12 . The material is not particularly in question so long as it can protect the electrode terminals 12 from a laser beam. In the present embodiment, the semiconductor wafer 10 is electrolessly plated with nickel to form a nickel layer on the surfaces of the electrode terminals 12 as a protective film 14 . By applying the treatment for selectively depositing electroless plating on the surfaces of the electrode terminals 12 to the semiconductor wafer 10 in advance, it is possible to form a protective film 14 simply on only the surfaces of the electrode terminals 12 by electroless plating. The protective film 14 should be formed to a thickness of about 10 to 20 μm.
Note that it is also possible to form a protective film 14 on the surfaces of the electrode terminals 12 , then gold plate, copper plate, etc. the surface of the protective film 14 to lower the contact resistance with the interconnect patterns electrically connecting with the electrode terminals 12 . The method of using electroless plating to form a protective film 14 or a gold plating film or copper plating film as in the present embodiment has the advantages that it does not require use of any special mask for forming the laser protective film, the processing work is easier compared with sputtering or another thin film processing step, and expensive systems compared with electroless plating systems such as thin film processing systems are not required.
FIG. 1C shows the state of grinding the side of the semiconductor wafer 10 opposite to the side of forming the electrode terminals 12 (back side of semiconductor wafer) to reduce the thickness of the semiconductor wafer 10 . By making the semiconductor wafer 10 thinner, the thickness of the semiconductor device as a whole becomes smaller and the semiconductor device can be formed compact. It is easy to use grinding to reduce a semiconductor wafer of a thickness of about 600 μm down to a thickness of about 100 to 200 μm. Note that the step of covering the surfaces of the electrode terminals 12 by a protective film 14 may also be performed after the processing for grinding the back side of the semiconductor wafer 10 . That is, it is also possible to grind the back side of the semiconductor wafer 10 , then perform treatment for selectively depositing an electroless plating on the surfaces of the electrode terminals 12 for electroless plating the surface so as to form a protective film 14 on the surface of the terminal electrodes 12 .
FIG. 1D shows the state after grinding the back side of the semiconductor wafer 10 , then covering the front side and back side of the semiconductor wafer 10 by resin layers 16 and 18 to form a laminate 20 . The resin layers 16 and 18 can be formed integrally with the semiconductor wafer 10 by using prepregs containing glass cloth used when producing ordinary resin boards to sandwich the semiconductor wafer 10 in the thickness direction and pressing and heating the same. The resin layers 16 and 18 act to protect the semiconductor wafer 10 by covering the front and back sides of the semiconductor wafer 10 .
If it were possible to suitably select the thermal expansion coefficient of the resin material used for the resin layers 16 and 18 so as to make the thermal expansion coefficient of the semiconductor device as a whole substantially match with the thermal expansion coefficient of the mounting circuit board, it would be possible to reduce the heat stress occurring between the semiconductor device and mounting circuit board when mounting a semiconductor device on a mounting circuit board. The thicknesses of the resin layers 16 and 18 in the embodiment are about 60 to 200 μm, but the thicknesses of the resin layers 16 and 18 may be set to thicknesses able to suitably ease the heat stress occurring between the solder balls or other external connection terminals and the connecting parts provided on the mounting circuit board when mounting a semiconductor device on a mounting circuit board in relation to the thermal expansion coefficient of the resin material used for the resin layers 16 and 18 . The resin layers 16 and 18 may use the same resin materials or may use different resin materials. The resin materials used for these resin materials 16 and 18 are selected in thermal expansion coefficients and thicknesses so that the laminate 20 does not warp when covering the two surfaces of the semiconductor wafer 10 and forming the laminate 20 .
At the step shown in FIG. 1C , the back side of the semiconductor wafer 10 is ground to reduce the thickness of the semiconductor wafer 10 so as to reduce as much as possible the contribution of the thermal expansion coefficient of the semiconductor chip comprised of silicon to the semiconductor device as a whole when forming a semiconductor device. As explained above, the thermal expansion coefficient of silicon is considerably different from the thermal expansion coefficient of the resin board used for the mounting circuit board.
Therefore, if it were possible to suppress the contribution of the thermal expansion coefficient from the semiconductor chip and use a material close to the thermal expansion coefficient of the resin material forming the mounting circuit board as the resin material used for the resin layers 16 and 18 , it would be possible to make the thermal expansion coefficient of the semiconductor device as a whole close to the thermal expansion coefficient of the mounting circuit board.
Note that as shown in FIG. 1D , when using the resin layers 16 and 18 to cover the two sides of the semiconductor wafer 10 and form a laminate 20 , there is no need to form the laminate 20 to an overall shape of the same circular shape as the semiconductor wafer 10 . It is sufficient to make it a rectangular shape or other shape facilitating the handling in later steps. The significance of making it a shape facilitating handling in later steps is that in the method of production of a semiconductor device of the present embodiment, production systems for the printed circuit board or other resin board are utilized to produce a wafer level package, so forming the laminate 20 to a shape facilitating handling in such production systems facilitates utilization of conventional systems.
FIG. 1E shows the state of formation of via holes 22 in the resin layer 16 by laser processing. A laser beam is focused at the positions of arrangement of the electrode terminals 12 to form the via holes 22 . The via holes 22 are provided so that the protective film 14 covering the electrode terminals 12 is exposed at the bottom surface. The surfaces of the electrode terminals 12 is covered by the protective film 14 , so the electrode terminals 12 will not be damaged by the laser beam.
FIG. 1F shows the state of electroless copper plating of the laminate 20 for formation of a plating power feed layer 24 over the entire surface of the resin layer 16 including the inside surfaces of the via holes 22 . The plating power feed layer 24 is for forming conductor parts serving as interconnect patterns by electroplating. FIG. 1G shows the state of exposure of parts for forming the interconnect patterns and covering the surface of the plating power feed layer by resist patterns 26 . The resist patterns 26 can be formed by covering the surface of the resin layer 16 covered by the plating power feed layer 24 by a dry film or other photosensitive resin coating and exposing and developing the same.
FIG. 1H shows the state of electrolytically copper plating the surface to build up copper plating 28 at exposed locations of the plating power feed layer 24 , then removing the resist patterns 26 . The copper plating 28 fills the via holes 22 and is formed to a predetermined thickness at exposed parts of the plating power feed layer 24 on the surface of the resin layer 16 . In the present embodiment, the parts of the copper plating filled in the via holes 22 become the vias 28 a , while the parts of the copper plating formed at the surface of the resin layer 16 become the lands 28 b . FIG. 1I shows the state of removal of parts of the plating power feed layer 24 exposed on the surface of the resin layer 16 and formation of conductor parts to which the individual electrode terminals 12 and lands 28 b are individually independently electrically connected via the vias 28 a . The thickness of the plating power feed layer 24 is much smaller than the thickness of the copper plating 28 of the lands 28 b etc., so the exposed parts of the lands 28 b are not covered by the resist etc. and a ferric chloride or other copper etching solution is used to chemically etch the laminate 20 so as to remove the exposed parts of the plating power feed layer 24 .
FIG. 1J shows the state of bonding of solder balls 30 as external connection terminals to all of the lands 28 b exposed at the outer surface of the resin layer 16 . Due to this, a laminate with solder balls 30 electrically connected with the electrode terminals 12 of the semiconductor wafer 10 provided at the outer surface of the resin layer 16 is obtained. FIG. 2 shows a semiconductor device (wafer level package) obtained by dicing the laminate 20 shown in FIG. 1J formed in a wafer shape into individual pieces. When dicing the laminate 20 , it should be diced at the boundary positions of the individual semiconductor chips formed at the semiconductor wafer 10 .
The semiconductor device 32 shown in FIG. 2 is comprised of a semiconductor chip 10 a covered by resin layers 16 and 18 at the front and back sides, having solder balls 30 bonded to lands 28 b formed on the surface of the resin layer 16 , and having solder balls 30 and electrode terminals 12 of the semiconductor chip 10 a electrically connected through the vias 28 a . When mounting the semiconductor device 32 , it is sufficient to bond the solder balls 30 positioned at the connecting parts provided at the mounting circuit board.
The two surfaces of the semiconductor chip 10 a are covered by the resin layers 16 and 18 , so the semiconductor chip 10 a is reliably protected. The back side of the semiconductor chip 10 a is not exposed to the outside, so interconnects etc. will not contact the outer surface of the semiconductor chip 10 a and cause an electrical short-circuit. When mounting the semiconductor device to a mounting circuit board, the resin layers 16 and 18 act to ease heat stress caused between the solder balls 30 and the connection terminals. Therefore, it is possible to eliminate the problem of the concentration of heat stress and the occurrence of cracks at the bonding parts of the solder balls 30 and connection terminals.
Note that with the method of production of a semiconductor device shown in FIGS. 1A to 1 J and FIG. 2 , starting from the step of forming the protective film 14 on the electrode terminals 12 formed on the semiconductor wafer 10 , the method of production used in a conventional resin board production process is utilized. In particular, the step of forming the conductor parts for electrical connection with the electrode terminals 12 shown in FIG. 2 utilizes the semiadditive method frequently used in the past as the method for production of resin boards. In this way, the present embodiment is characterized by using the production method and apparatus used conventionally for a production method of a resin board for formation of a semiconductor device (wafer level package).
In the embodiment shown in FIGS. 1A to 1 J and FIG. 2 , lands 28 b were simply formed in the same arrangement as the electrode terminals 12 of the semiconductor wafer 10 , but it is also possible to produce a semiconductor device by laying interconnect patterns on the surface of the semiconductor wafer 10 . FIGS. 3A to 3 E show the steps of covering the front and back sides of the semiconductor wafer 10 by the resin layers 16 and 18 (FIG. 3 A), forming via holes 22 at the resin layer 16 (FIG. 3 B), forming a plating power feed layer 24 over the entire surface of the resin layer 16 including the via holes 22 by electroless copper plating (FIG. 3 C), forming resist patterns 26 a on the surface of the resin layer 16 (FIG. 3 D), and electroplating copper to form a conductor layer forming the interconnect patterns (redistribution patterns) 28 c and bonding solder balls 30 to the land parts of the interconnect patterns 28 c so as to form a laminate (FIG. 3 E).
As shown in FIG. 3D , the interconnect patterns 28 c forming reinterconnects are formed on the surface of the resin layer 16 in a state electrically connected with the electrode terminals 12 through the vias 28 a . It is possible to obtain the laminate shown in FIG. 3E by removing the resist patterns 26 a , etching away the plating power feed layer 24 exposed at the surface of the resin layer 16 and covering the surface of the resin layer 16 by the insulating resin 34 so as to leave exposed only lands of the interconnect patterns 28 c , then bonding solder balls 30 to the lands. A semiconductor device is obtained by dicing the laminate shown in FIG. 3E into individual pieces. The semiconductor device is obtained in the form with the electrode terminals 12 and interconnect patterns 28 a electrically connected through the vias 28 a and with solder balls 30 bonded to the lands provided at the interconnect patterns 28 a.
In the method of production of a semiconductor device shown in FIGS. 3A to 3 E, only one layer of interconnect patterns 28 c is formed on the surface of the resin layer 16 . FIGS. 4A to 4 D show an example of stacking a plurality of layers of interconnect patterns through electrical insulating layers. FIG. 4A shows the state of formation of a first layer of interconnect patterns 28 c on the surface of the resin layer 16 electrically connected with the electrode terminals 12 c . FIG. 4B shows the state of formation of a resin layer 17 above the interconnect patterns 28 c and formation of via holes 22 by laser processing the resin layer 17 . FIG. 4C shows the state of formation of a second layer of interconnect patterns 28 d on the surface of the resin layer 17 utilizing the plating power feed layer 24 to electrically connect with the underlying interconnect patterns 28 c.
FIG. 4D shows the state of covering the surface of the resin layer 17 by an insulating resin 34 a so as to leave exposed only lands of the interconnect patterns 28 , then bonding solder balls 30 to the lands. In this way, it is possible to electrically insulate layers from each other by the resin layers 16 and 17 on the electrode terminal forming surface of the semiconductor wafer 10 and obtain a laminate with electrode terminals 12 and solder balls electrically connected through the two layers of interconnect patterns 28 c and 28 d . By dicing the laminate into individual pieces, it is possible to obtain a semiconductor device (wafer level package).
According to the method of production of a semiconductor device shown in FIGS. 4A to 4 D, by dicing the laminate into individual pieces, it is possible to obtain a semiconductor device comprised of a semiconductor chip 10 a on the electrode terminal forming surface of which a plurality of interconnect layers are formed. In this way, when forming interconnect patterns on the electrode terminal forming surface of the semiconductor wafer 10 , it is possible to form interconnect patterns in any pattern and possible to form a plurality of interconnect layers stacked together. The method of forming these interconnect patterns utilizes the conventional method of production of a resin board as it is and is not particularly complicated in steps. Further, the method of production of a semiconductor device of the present method, as explained above, does not depend on sputtering or other thin film processes, so it is possible to utilize conventional production systems utilized for production of resin boards. Particularly, there is no need to use an expensive production system.
Summarizing the effects of the invention, according to the method of production of a semiconductor device according to the present invention, as explained above, starting from the step of forming a protective film on the electrode terminals of the semiconductor wafer, it is possible to utilizing a conventional method of production of a resin board to produce a semiconductor device without using an expensive production system for semiconductor devices and thereby possible to keep down the cost of production of a semiconductor device. In particular, even when processing a semiconductor wafer larger than in the past, it is possible to utilize a conventional production system for resin boards. Therefore, there is no need to construct a new production system and the investment cost can be suppressed.
Further, the semiconductor device obtained by the method of the present invention is covered at the two surfaces of the semiconductor chip by a resin layer so there are the advantages that the semiconductor chip is reliably produced and the heat stress acting on the external connection terminals when mounting the semiconductor device by a resin layer can be eased.
While the invention has been described with reference to specific embodiments chosen for purpose of illustration, it should be apparent that numerous modifications could be made thereto by those skilled in the art without departing from the basic concept and scope of the invention. | A method of production of a semiconductor device able to utilize a conventional production system for a resin board to thereby produce a wafer level package without increasing the production cost, comprising electrolessly plating the electrode terminals to cover the surfaces of the electrode terminals by a protective film protecting the electrode terminals from laser beams; grinding the back side of the semiconductor wafer to reduce the thickness of the semiconductor wafer before or after forming the protective film; covering the entirety of the electrode terminal forming surface and back side of the semiconductor wafer, having the electrode terminals covered by a protective film and processed to reduce the thickness of the semiconductor wafer, by a resin to form a laminate; and focusing a laser beam toward the electrode terminal forming surface of the semiconductor wafer from outside the laminate to form via holes with the protective film exposed at their bottom surfaces, then filling the via holes by electroplating to form the conductor parts. | 7 |
RELATED APPLICATIONS
This application is related to co-pending applications: Ser. No. 10/170,978, filed Jun. 13, 2002, entitled, “GIMBAL FOR SUPPORTING A MOVEABLE MIRROR”; and Ser. No. 10/171,298, filed Jun 13, 2002, entitled, “PHOTONIC SWITCH FOR AN OPTICAL COMMUNICATION NETWORK”; both of which are assigned to the assignee of the present application.
FIELD OF THE INVENTION
The present invention relates generally to apparatus and methods for movement of objects; specifically, objects such as mirrors that direct light beams in optical systems and networks.
BACKGROUND OF THE INVENTION
Fiberoptic technologies and systems have been widely deployed in recent decades. However, certain key components remain expensive and inefficient, which hinders the expansion of optical systems and optical communication networks. One of these components is the wavelength switch, which routes and redirects a light beam from one fiber to another fiber so that the signal can be provisioned and managed according to the demand. A typical wavelength switch used today converts the input light signal into an electronic signal to detect the routing information, switches the electronic signal, and then eventually reconverts it back into a light signal for further transmission. This device, commonly referred to as an Optical-Electrical-Optical (OEO) switch, not only depends on current semiconductor technologies and processes, but also requires a transmitter and a receiver for each transmission port. These factors cause OEO switches to be large in size (e.g., occupying two or more 7-foot tall racks), to have high power consumption (e.g., kilowatts), to be network protocol and transmission rate dependent, to lack scalability, and to be costly.
Thus, there is a need for an alternative apparatus for directing a light beam in an optical system that can be manufactured efficiently and provide improved performance in optical systems and fiber optic-based networks.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be understood more fully from the detailed description that follows and from the accompanying drawings, which however, should not be taken to limit the invention to the specific embodiments shown, but are for explanation and understanding only.
FIGS. 1A & 1B are top views of a gimbal used in accordance with one embodiment of the present invention.
FIG. 2 illustrates a platform that mounts to the gimbal of FIGS. 1A & 1B in an actuator-mirror assembly according to one embodiment of the present invention.
FIG. 3 is a bottom perspective view of an integrated mirror/pedestal 210 utilized in accordance with one embodiment of the present invention.
FIG. 4 illustrates an actuator-mirror assembly at an intermediate point of construction according to one embodiment of the present invention.
FIG. 5 illustrates an actuator-mirror assembly at a further point of construction according to one embodiment of the present invention.
FIG. 6 is a perspective view of an actuator-mirror assembly according to another embodiment of the present invention.
FIGS. 7A & 7B are top and side views of a magnet-housing arrangement for an actuator-mirror assembly in accordance with one embodiment of the present invention.
FIG. 8 is a top view of a magnet-housing arrangement for an actuator-mirror assembly in accordance with another embodiment of the present invention.
FIG. 9 is a cross-sectional side view of an actuator-mirror assembly according to one embodiment of the present invention.
FIGS. 10A & 10B are cross-sectional side views of an actuator-mirror assembly tilted in two different directions in accordance with one embodiment of the present invention.
FIGS. 11A & 11B show top and side views of a bobbin coil assembly utilized in accordance with an alternative embodiment of the present invention.
FIG. 12 illustrates the relative position of a coil and magnet assembly in accordance with an alternative embodiment of the present invention.
FIG. 13 is a top view of a gimbal utilized in accordance with an alternative embodiment of the present invention.
FIG. 14 is a cross-sectional side view of an actuator-mirror assembly in accordance with an alternative embodiment of the present invention.
DETAILED DESCRIPTION
An actuator and a mirror assembly to guide a light beam for a variety of applications is described. In the following description numerous specific details are set forth, such as angles, material types, configurations, etc., in order to provide a thorough understanding of the present invention. However, persons having ordinary skill in the opto-mechnical arts will appreciate that these specific details may not be needed to practice the present invention.
According to one embodiment of the present invention, a tilting actuator-mirror assembly is provided to control the path of a light beam. The present invention has numerous consumer, medical, and/or industrial applications. For example, laser marking, laser display, optical scanning devices, windshield auto projection, helmet display, personal digital assistant (“PDA”), fiber optic communication network (e.g., an all-optical switch), and mobile phone projection display, to name a few, can all benefit from the present invention.
In a particular embodiment, a dual-axis tilting actuator is provided as a rotary moving coil actuator suspended by a flexing, electrically conductive gimbal component. The gimbal is comprised of a pair of beams that move about the axis of rotation under the influence of an electromagnetic actuator. The conductive connections in the rotary moving coil actuator are integrated with the flexing part of the gimbal. In various embodiments, the actuator may rotate about either a single axis or a dual axis.
Referring now to FIGS. 1A & 1B, there is shown a top plan view of a gimbal 200 utilized in accordance with one embodiment of the present invention. Gimbal 200 is made from a single, integral sheet of thin metal. FIG. 1A shows gimbal 200 after removal of the “cutout” areas from the sheet metal. FIG. 1B shows the gimbal after removal of the end section and perimeter material, which step is performed during the construction of the actuator-mirror assembly according to one embodiment of the present invention.
The sheet metal used for gimbal 200 is preferably a fully hardened material, such as stainless steel, having high fatigue strength. Other materials providing similar properties may also be used. The material selected should allow the gimbal to rotate the attached mirror (or mirror-coil assembly) with a high rotational angle (e.g., +/−15 degrees) over millions of movement cycles. The material may also be heat-treated. The sheet metal material is also preferably non-magnetic to prevent reluctance forces induced by the magnets in the actuator. In some cases, the sheet metal may also be coated with a corrosion-resistant material, such as titanium-nickel or gold.
Gimbal 200 comprises four attachment pads 201 - 204 that are centrally located symmetrical about the x-axis (i.e., longitudinal axis) and y-axis (i.e., transverse axis). A mirror, or mirror-pedestal assembly, is adhesively attached to pads 201 - 204 . Thus, in the completed assembly, pads 201 - 204 are all affixed in a rigid plane, remaining stationary or moving in unison, depending on the particular embodiment of the final actuator-mirror assembly. Thin, elongated beams 191 - 194 support each of pads 201 - 204 , respectively. In operation, pairs of adjacent beams 191 & 192 and 193 & 194 each twist longitudinally about the x-axis to permit the mirror (attached to pads 201 - 204 ) to rotate about the x-axis.
In FIG. 1A, beams 191 & 192 are shown being integrally connected to end section 251 through respective intermediate sections 221 & 222 . Similarly, beams 193 & 194 are integrally connected to end section 253 through intermediate sections 223 & 224 , respectively. Intermediate sections 221 - 224 are also integrally connected with thin, elongated beams 195 - 198 , respectively, which permit rotation of the mirror about the y-axis. During rotation of the mirror about the x-axis, pairs of adjacent beams 195 & 196 and 197 & 198 remain substantially rigid. Similarly, during rotation of the mirror about the y-axis, pairs of adjacent beams 195 & 196 and 197 & 198 twist longitudinally about the y-axis, while pairs of adjacent beams 191 & 192 and 193 & 194 remain substantially rigid.
Beams 195 & 196 are shown in FIG. 1A being connected to end section 252 via respective L-shaped mounting sections 240 & 241 . Likewise, beams 197 & 198 are both integrally connected to end section 254 through respective L-shaped mounting sections 242 & 243 . All of the end sections 251 - 254 are attached together through a set of perimeter connecting sections 246 - 249 . For example, end section 251 attaches to end sections 252 & 254 via connecting sections 246 & 249 , respectively. End section 253 attaches to end sections 252 & 254 via connecting sections 247 & 248 , respectively. In this embodiment, end sections 251 - 254 (beyond dashed lines 250 in FIG. 1A) are removed along with the perimeter connecting sections during the assembly process. FIG. 1B shows gimbal 200 after these metal sections have been removed. This assembly process of this embodiment is described in more detail below.
Each of the mounting sections 240 - 243 of gimbal 200 is fixedly mounted (e.g., with adhesive) to a stationary point or platform mount of the actuator-mirror assembly. FIG. 2 shows one possible implementation of a platform 270 that may be used for this purpose. Platform 270 comprises a base 271 that supports four rigid posts 272 - 275 of equal height. Each of the posts 272 - 275 has a flat end surface 282 - 285 , respectively. The dimensions of end surfaces 282 - 285 and the position of posts 272 - 275 is such that end surfaces 282 - 285 align with the rectangular surface areas of mounting sections 240 - 243 (see FIG. 1B) in a corresponding manner. This permits the mounting sections 240 - 243 to be adhesively attached to corresponding end surfaces 282 - 285 .
FIG. 2 also shows a set of four thin wires 292 - 295 , each of which is adhesively bonded to respective posts of platform 282 - 285 . These wires connect with the coils that comprise the actuator of the final assembly. Two of the wires are used to energize the coils disposed about the x-axis, and the other two are used to energize the coils disposed about the y-axis.
After gimbal 200 has been mounted to platform 270 each of the wires 292 - 295 are soldered to corresponding tabs of the mounting sections 240 - 243 . For example, if surface 282 is attached to mounting section 240 , wire 292 may be soldered to tab 255 . Continuing with this example, with surfaces 283 - 285 respectively attached to mounting sections 241 - 243 , wires 293 - 295 may be soldered to tabs 256 - 258 , respectively. Note that in gimbal 200 of FIG. 1B each of tabs 255 - 258 provides separate electrical connection with respective pads 202 , 203 , 204 , and 201 . This feature is utilized to establish electrical connection to the coils of the actuator-mirror assembly, as discussed in more detail shortly.
Metal may be removed from a single piece of thin sheet metal to achieve the gimbal cutout patterns shown in FIGS. 1A & 1B using a variety of conventional methods, such as chemical etching, press cutting, milling, etc. Although a specific rectilinear cutout pattern is shown in these figures, it is understood that other embodiments may have different patterns or a different arrangement of beams, pads, etc., yet still provide rotational movement along the x and y axes in accordance with the present invention.
In the embodiment illustrated by FIGS. 1A & 1B, beams 191 - 198 are each about 0.05 mm wide, mirror-attachment pads 201 - 204 are each about 0.4 mm×0.6 mm in dimension, and the thickness of the single piece of sheet metal is about 0.0254 mm. Wires 292 - 295 are also about 0.0254 mm thick. In certain embodiments, beams 191 - 198 may be partially etched to make them thinner than the rest of the sheet metal material. For example, beams 191 - 198 may be chemically etched to a thickness less than 0.0254 mm to increase flexibility and thus achieve a higher degree of rotation.
FIG. 3 is a bottom perspective view of an integrated mirror/pedestal 210 utilized in accordance with one embodiment of the present invention. In the drawing, the polished, reflective surface of mirror 214 faces down and into the page. Integrated mirror/pedestal 210 may be manufactured from a single piece of material such as silicon, Pyrex®, quartz, sapphire, aluminum, or other types of suitable materials. Integrated mirror/pedestal 210 includes a pedestal portion 212 having a flat surface 211 . The length and width of surface 211 is such that it matches or fit within the combined area of pads 201 - 204 (see FIG. 1 B). During the assembly process, surface 211 is adhesively bonded to one side of pads 201 - 204 .
Integrated mirror/pedestal 210 also includes a base plate 213 between pedestal portion 212 and the back of mirror 214 . Base plate is sized smaller than mirror 214 such that a step 216 , comprising a peripheral area of the back of mirror 213 , is realized. It is appreciated that other embodiments may be constructed from discrete parts (e.g., separate mirror, base plate, and pedestal) rather than being manufactured in integral form. In either approach, the mirror may be about 0.25 mm thick and 2×2 mm in area. The mirror surface may be lapped to a highly polished optical-flat surface. A reflective surface can also be applied by numerous methods, including plating or sputtering gold, silver, or aluminum on a layer of nickel.
FIG. 4 shows a bottom perspective view of an actuator-mirror assembly after pads 201 - 204 have been bonded to surface 211 of integrated mirror/pedestal 210 . FIG. 4 also shows four coils 206 - 209 adhesively bonded to step 216 around the side back surface of mirror 214 . Thus, coils 206 - 209 , mirror 214 , and pads 201 - 204 of gimbal 200 are all rigidly coupled together, and move as a single unit, in the actuator-mirror assembly according to one embodiment of the present invention. Note that although FIG. 4 shows the end sections of gimbal 200 before removal at this stage of the assembly process, this is not required. That is, the end and peripheral connecting sections of gimbal 200 may be removed either before or after attachment to the mirror/pedestal assembly.
FIG. 5 is another view of the assembly of FIG. 4 after soldering of pairs of coil wires to the back of pads 201 - 204 . (Note that not all of the cutout portions of the gimbal are shown in this view for clarity reasons.) For example, wires 226 & 227 of coil 208 , and wires 224 & 225 of coil 206 , are shown soldered to pads 202 & 203 , respectively. Similarly, wires 228 & 229 of coil 207 , and wires 230 & 231 of coil 209 , are soldered to pads 204 & 201 , respectively.
Upon removal of the end sections of gimbal 200 , each of the pads 201 - 204 is electrically connected to a separate one of the mounting sections 240 - 243 . In other words, removal of the end sections of the gimbal creates four distinct conductive paths in the remaining sheet metal material from each of the four mounting sections to a corresponding one of the pads 201 - 204 . According to one embodiment of the present invention, current flows through these four paths to control movement of the attached mirror via coils 206 - 209 . This embodiment therefore utilizes the metal of gimbal 200 to conduct electrical current delivered to the moving coil. That is, the electrical connections to the coil wires are integrated with the flexing part of the gimbal. This arrangement thereby eliminates movement of wires during operation of the mirror-gimbal assembly.
Following attachment of the gimbal to platform 270 (see FIG. 2) wires 292 - 295 may be soldered to tabs 255 - 258 to establish an electrical connection to coils 206 - 209 . Thus, the conductive paths provided through the flexing beams of gimbal 200 may be used to energize the coils in order to control tilting of the mirror along the x-axis and the y-axis. By way of example, one pair of wires 292 - 295 may be used to energize one pair of opposing coils (i.e., coils 207 & 209 ) to control rotation of the mirror about the x-axis, with the remaining pair of wires 292 - 295 being used to energize the other pair of opposing coils (i.e., coils 206 & 208 ) to control rotation of the mirror about the y-axis. In the final assembly, permanent magnets are attached within the central opening of each of the coils 206 - 209 .
Torque is developed on the mirror-coil assembly upon application of an appropriate current through the coils, in the presence of the permanent magnetic field. The direction of the force is made to be opposite on each side of the mirror-coil assembly such that the resulting torque rotates or tilts the mirror attached to the top of gimbal 200 . Since the mirror-coil assembly is fixedly attached to gimbal 200 , gimbal pads 201 - 204 and mirror 214 rotate together as the mirror-coil assembly rotates. When the applied current is interrupted or halted, the restoring spring force of gimbal 200 returns the assembly to a rest position.
FIG. 6 is a perspective view of another embodiment of an actuator-mirror assembly according to the present invention. The actuator-mirror assembly shown in FIG. 6 rotates about a single axis. In this embodiment, two coils 50 and 55 are adhesively attached to step 216 on opposite sides of mirror 214 and base plate 213 . The gimbal for this embodiment comprises two rectilinear, or I-bar, shaped members 10 a & 10 b of thin sheet metal. Ends 12 a & 12 b of respective I-bar members 10 a & 10 b are bonded to surface 211 of pedestal 212 . Wires 60 a & 60 b of coil 50 are soldered to ends 12 a & 12 b , respectively. Likewise, wires 65 a & 65 b of coil 55 are also soldered to ends 12 a & 12 b , respectively. A stationary platform similar to that shown in FIG. 2, but having two posts, supports the assembly of FIG. 6, with the end surfaces of the posts being bonded to ends 14 a & 14 b of I-bar members 10 a & 10 b . A wire attached to each of the mounting posts may be soldered to ends 14 a & 14 b to provide electrical connection through the gimbal members 10 a & 10 b to energize coils 50 & 55 .
FIGS. 7A & 7B show top and side views of a magnet-housing arrangement for a single actuator-mirror assembly in accordance with one embodiment of the present invention. This magnet-housing arrangement, for example, may be utilized in the actuator-mirror assembly shown in FIG. 4 . Magnets 81 - 84 are bonded on the side surfaces of steel returns 85 , attached to a base 86 . Magnets 81 - 84 are positioned adjacent the moving coils (e.g., coils 206 - 209 ). The polarities of the magnets are shown by conventional nomenclature for north (N) and south (S). In one embodiment, the magnet material is Neodymium-Iron-Boron. Of course, other types of magnetic materials may be used as well.
FIG. 8 shows a top view of a larger magnet-housing arrangement for use with multiple actuator-mirror assemblies.
FIG. 9 is a cross-sectional side view of an actuator-mirror assembly utilizing gimbal 200 according to one embodiment of the present invention. A pair of magnets 87 is shown attached to a steel return on opposite sides of the mirror-coil-gimbal assembly. One pair of magnets 87 are positioned adjacent coil 206 , and the other pair of magnets 87 are positioned adjacent coil 209 . Each of the coils is bonded to a notched edge surface of mirror plate 214 . A pedestal 212 is shown attached to the back of mirror plate 214 and also to pads 201 & 202 of gimbal 200 . The end surfaces of posts 74 & 75 are shown respectively bonded to mounting sections 240 & 243 , with wires 94 & 95 soldered to sections 240 and 243 in accordance with the wiring scheme described above.
Also included in the cross-section of FIG. 9 is an optional balancing plate 80 attached to the bottom of the coils 206 - 209 . Balancing plate 80 acts to counterbalance the weight of the mirror so that the center of rotation is at the center of gravity. This feature improves external shock and dynamic settling of the actuator. As shown in FIG. 9, balancing plate 80 comprises a solid, flat metal plate with several openings that allow the stationary posts to attach to the gimbal and also permit the gimbal-mirror-coil assembly to move. Instead of having several openings to accommodate mounting of the mirror-coil-gimbal onto stationary posts, balancing plate 80 may also be implemented with a single, centrally located opening. For instance, balancing plate 80 may comprise a rectangular frame having its sides adhesively attached to the coils, as shown in FIGS. 10A & 10B.
The embodiment of FIG. 9 further illustrates the use of an optional damper coating 333 , which covers beams 191 - 198 and gimbal pads 201 - 204 . Damper coating 333 comprises a low viscosity polymer (e.g., an ultraviolet curing resin) that becomes a flexible gel upon curing. Damper coating 333 acts to damp gimbal resonances and improve the settling time of the actuator; yet, because coating 333 is flexible, it does not appreciably affect the stiffness of the gimbal. Damper coating 333 also improves reliability by minimizing the effect of external shock and vibration.
FIGS. 10A & 10B are cross-sectional side views of an actuator-mirror assembly with appropriate current applied to coils 206 & 209 to tilt mirror 214 in two different directions along a single longitudinal axis of movement. Note that in FIGS. 10A & 10B only the rigid sections of gimbal 200 are shown for clarity reasons. Precise movement of mirror 214 along both the x-axis and y-axis is achieved by controlling the current applied to the four coils 206 - 209 for the embodiments described above.
FIGS. 11A & 11B show top and side views of a bobbin-coil assembly utilized in accordance with an alternative embodiment of the present invention. In this embodiment, the coils 301 , 302 , 303 , and 304 are made from fine copper wire with single-built insulation, and are each wrapped around a post member on a side of bobbin 310 . Coils 301 , 302 , 303 , and 304 are physically located between one or more permanent magnets (not shown in this view) in the final assembly. FIG. 12 shows the relative position of a coil and magnet assembly in accordance with this alternative embodiment. The coil windings are supported by and encircle the protruding side members of bobbin 310 , shaped in accordance with the dimensions of the permanent magnets. Bobbin pedestal 330 provides a surface for bonding (e.g., adhesive attachment) to a gimbal that suspends bobbin 310 between the permanent magnets.
By way of example, in the embodiment of FIGS. 11A & 11B, each coil may include approximately 48 turns made from 6 layers, with each layer having 8 turns. The number of turns and layers may vary based on the type of coil used, the application, etc. Bobbin 310 may be made from a variety of machined materials (e.g., polymers) as is known in the art. In operation, application of current through the coils generates a magnetic field that interacts with the field of the permanently mounted magnets to torque to tilt the actuator.
The bobbin coil assembly of FIGS. 11A & 11B may be bonded to a variety of conventional gimbals. FIG. 13 shows a top view of a conventional gimbal 320 of a type well known in the industry, which may be used to suspend the bobbin-coil assembly shown in FIGS. 11A & 11B. Gimbal 320 is formed of a single sheet of material (e.g., sheet metal) that provides for dual-axis rotation of the bobbin-coil assembly. Bobbin pedestal 330 may, for instance, be bonded to central area 323 of gimbal 320 .
FIG. 14 shows a cross-sectional side view of an actuator-mirror assembly in accordance with an alternative embodiment of the present invention. In this view, permanent magnets 396 & 397 are positioned on steel returns 395 & 394 adjacent coils 381 & 382 , respectively. Coils 381 & 382 are located on opposite sides of a bobbin 310 , which is bonded to the center of a gimbal 320 , such as that shown in FIG. 13 . In this example, gimbal 320 is secured to stationary steel returns 394 & 395 . A mirror 391 is secured on the center-top area of gimbal 320 .
Torque is developed on the bobbin-coil assembly upon application of an appropriate current through coils 381 & 382 , in the presence of the permanent magnetic field. The direction of the force is made to be opposite on each side of bobbin 310 such that the resulting torque rotates or tilts mirror 391 attached to the top of gimbal 320 . The bobbin-coil assembly is attached to a gimbal 320 and therefore the gimbal 320 and the mirror 391 will rotate as the bobbin-coil assembly rotates. When the applied current is interrupted or halted, the restoring spring force of gimbal 320 returns the assembly to the rest position shown in FIG. 14 . | An actuator for tilting a moveable object such as a mirror includes a base and a coil-object assembly that includes first and second pairs of coils each of which is attached to the object, the first pair of coils being arranged along a longitudinal axis, and the second pair of coils being arranged along a transverse axis substantially orthogonal to the longitudinal axis. A gimbal has an attachment section attached to the object, and mounting sections connected via a plurality of beams to the attachment section, the mounting sections being attached to the base. A permanent magnet is positioned adjacent a corresponding one of each of the coils such that when current flows through the coils a rotational force is generated that causes the coil-object assembly to rotate about an axis. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 61/078,373 filed Jul. 4, 2008 and is a Divisional application that is based on and claims priority to U.S. patent application Ser. No. 12/498,357, filed Jul. 6, 2009, the entirety of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to devices for playing horseshoe, bag toss, or bocce ball type games.
[0004] 2. Description of the Prior Art
[0005] The use of devices for playing horseshoe, bag toss, and bocce ball type of games is known in the prior art. More specifically, devices for playing horseshoe or bocce ball games heretofore devised and utilized are known to consist basically of familiar, expected and Obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
[0006] Known prior art devices for playing horseshoe and bocce ball type games include U.S. Pat. No. 6,015,151; U.S. Pat. No. 4,203,592; U.S. Pat. No. 5,125,669; U.S. Pat. No. 5,110,139; U.S. Pat. No. 3,119,619; U.S. Pat. No. 915,450; U.S. Pat. No. 7,314,420; PCT Patent No. WO 95/30457 (Inventors: Bouchard et at); and EPO Patent No. EP 0 310 054 A2 (Inventors: Norman et al).
[0007] While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose a new bounce-landing puck toss game device. In these respects, the bounce-landing puck toss game device of the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of playing a bounce-landing puck tossing game with a method of play distinctly different to horseshoe, bag toss, or bocce ball type games. For the record it should be clearly stated that bocce balls are not able to bounce-land either fully or partially supported onto each other. Bocce balls are round and they fall off of each other due to the effects of gravity and the roundness of the ball, thus differentiating this invention so as not to be considered a bocce-ball type of game. Prior art U.S. Pat. No. 6,015,151 does not disclose any design or method of play that includes a tossing device landing on a target device for premium points scored in any manner or function. While prior art U.S. Pat. No. 6,015,151 describes a disc toss bocce-ball type game, of which the actual size, weight, and construction material of the game apparatus, said disc does not permit prior art U.S. Pat. No. 6,015,151 apparatus to be functional and useful when applied to the new and different method of play of the invention of this application. In prior art U.S. Pat. No. 6,015,151 apparatus said disks are specified by claim to be “less than” a specific size diameter, thickness and weight, which often prohibits the desirable and practical function of play in the preferred environments of outdoor beaches, sandy areas, and parks due to the effects of normal and commonplace wind, and visibility. The normal and commonplace wind presents an adverse effect to player accuracy which prohibits the game of this invention to have the probability of accuracy necessary for said objective and desired successful bounce-landing toss at the said distance of up to about 50 (fifty) feet. The game apparatus of this invention is deliberately designed to be of sufficient weight, diameter, and thickness as to overcome and minimize the adverse effects of the wind in regards to player accuracy, while said puck is tossed and in flight at the designated distance of up to about 50 (fifty) feet.
[0008] The game apparatus said tossing and target pucks of this invention are comprised and constructed of a material that is of sufficient weight or specific gravity at the said thickness and diameter, to provide the necessary momentum when tossed, to overcome the inherent adverse effects that the wind presents in regards to player accuracy, and therefore enjoyment. The composition of the material of the game of this invention is an injection moldable plastic, more specifically an elastomer of 30 percent to 70 percent combined with a polypropelene of 30 percent to 70 percent, of which an ideal percentage is dependent on the specific differences of manufacturer of the material and injection molding requirements. The said “marker disc” of U.S. Pat. No. 6,015,151 is specified by claim to be “less than” a specific size; therefore, is prohibitively small in size diameter and thickness dimension to ensure the visibility needed to be a target in normal and commonplace piles of sand and long turf grass lawns as intended area for the game of this invention to be played. The game apparatus of this invention comprises a much larger target puck compared to prior art U.S. Pat. No. 6,015,151 disclosures, and is to be white or of other substantially bright and easily delineated color, in contrast to the colors of the said tossing pucks and various surfaces of play, thus clearly improving the visibility of said target puck, and achieving a more desirable function of play.
[0009] The said “marker disc” of U.S. Pat. No. 6,015,151 is specified by claim to be “less than” a specific size; therefore, is prohibitively small in size diameter and thickness dimension to enable the method of play and objective of the game of this invention, which is more specifically to toss and bounce-land said tossing puck or a plurality of said tossing pucks onto said target puck in a fully supported or partially supported position from a distance of up to about 50 (fifty) feet. The game apparatus of this invention comprises a much larger target puck face surface area, and thus functions with a desirable probability of landing a single or a plurality of said tossing pucks onto said target puck during the course of one single completed turn of four said tossing pucks being tossed by a player and opponent.
SUMMARY OF THE INVENTION
[0010] The present invention provides anew competitive bounce-landing puck toss game. This game and method of play surpass inherent barriers of prior art apparatus and devices to enable the challenging and competitive play often sought by the general public for entertainment. The game design and construction enhance the integrity of players ability and accuracy of play resulting in desirable scoring, thus increasing the entertainment and competitive value.
[0011] The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new bounce-landing puck toss game device apparatus and method of play which has many advantages in comparison to relevant prior art devices for playing horseshoe, bag toss, and bocce-ball type games mentioned heretofore, and many novel features that result in a new bouncelanding puck toss game device which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art devices for playing horseshoe or bocce-ball games or apparatus, either alone or in any combination thereof.
[0012] Each puck has one said perpendicular perimeter side edge to said puck face being a sharp 90 degree angle and said opposite puck face having a less sharp perpendicular perimeter side edge to puck face angle of 90 degrees with about a 1/32 inch to 114 inch corner radius with an ideal corner radius of 1/16 inch.
[0013] The game apparatus consists of eight tossing pucks divided equally into two sets and one target puck. Each set of tossing pucks is a color easily recognized as being different from the other and both sets of pucks being of a color that is distinctly different from the target puck color. The target puck is substantially equal in construction to the tossing pucks with the one exception of color. The target puck is ideally a bright while color.
General Outline for the Preferred Method of Play
[0014] The preferred said method of play consists of a plurality of players, with each player or team of players tossing a set of four (4) colored pucks towards the previously tossed brightly colored or white target puck.
[0015] The preferred said method of play allows a player to select which of the two faces of any puck is in the upward position in an attempt to provide the desired initial desired striking contact to the playing surface or the previously tossed pucks. By selecting which face of the puck is facing up when tossed, the player is also selecting which said 90 degree face to side edge corner of the downward face of the puck, the sharp no-radius corner, Or the more rounded-radius corner will make initial contact with the playing surface or previously tossed puck or pucks as desired. This aforementioned playing technique changes the initial contact of said sharper no-radius corner of the puck about to be tossed resulting in a more abrupt stop and bounce backward effect as compared to said rounded-radius corner resulting in a more of a bounce and slide forward technique.
[0016] The preferred said method of play is for tossing said tossing pucks a distance of at least about ten (10) feet and up to about fifty (50) feet from the line of toss to where the said tossing puck lands, with the primary and highest scoring objective to bounce-land said tossing puck onto said target puck so that said tossing puck is fully supported by said target puck, or the inverse thereof.
[0017] The preferred said method-of play is fur tossing said tossing pucks a distance of up to about fifty (50) feet from the line of toss to where the said tossing puck lands, with the secondary and second highest scoring objective to bounce-land said tossing puck onto said target puck so that said tossing puck is partially supported or leaning on said target puck, or the inverse thereof.
[0018] The preferred said method of play is for tossing said tossing pucks a distance of up to about fifty (50) feet′ from the line of toss to where the said tossing puck lands, with the lowest scoring objective to bounce-land said tossing puck closest to said target puck.
[0019] The preferred said method of play is that the game commences with one of the teams players tossing the white target puck a distance of at least about ten (10) and up to a distance of about 50 (fifty) feet from the line of toss.
[0020] The preferred said method of play after the first toss of a tossing puck allows the player with the inferior scoring position to continue to toss until the last previously tossed puck results in that player or team to be in a superior scoring position, or until all four tossing pucks have been tossed for that turn of play.
[0021] The preferred said method of play is for only one player or team to score for each turn of play.
[0022] The preferred said method of play is for the player or team scoring points in the previous turn to begin the next turn by again tossing the target puck up to a distance of about fifty (50) feet and then toss the first of the four tossing pucks towards the target puck.
[0023] The preferred said method of play is primarily to attempt to land a tossing puck onto the target puck in a fully supported position for the highest scoring value of six (6) points, and secondarily to land one or more tossing pucks onto the target puck in a partially supported or leaning position to score three (3) points for each, and the minimal scoring position of landing one or more tossing pucks closer to the target than the other player to score one (1) point for each puck that is closer than any of the opponents.
[0024] With respect to the above description then, it is to he 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.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The invention will be better understood and the 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:
[0026] FIG. 1 is a plan view of a bounce-landing puck according to the present invention.
[0027] FIG. 2 is a section view of the puck of the present invention.
[0028] FIG. 3 is a plan view of the game apparatus of the present invention.
[0029] FIG. 4 is a perspective view of puck scoring positions according to the method of play of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0030] With reference now to the drawings, and in particular to FIGS. 1 through 4 thereof, a new bounce-landing puck toss game device embodying the principles and concepts of the present invention.
[0031] FIG. 3 comprises a plurality of pucks including a number of tossing pucks 10 and a target puck 15 . Each puck has a center, generally circular first and second faces and a perimeter side edge between the first and second faces of the puck. Each puck has a generally cylindrical bore 13 extending between its first and second faces.
[0032] Ideally, the number of tossing pucks comprises eight tossing puck˜and are preferably divided equally into a pair of sets each having a common marking or color on each of the pucks of the set, with each set being a different color. Each puck has a center, generally circular first and second faces and a perimeter side edge between the first and second faces of the puck. FIG. 2 shows each puck has two perimeter side edges, one with a sharp 90 degree corner 11 with no radius, and the other with a more rounded 90 degree corner 12 with a radius of 1/32 inch to 1:4 inch with ideal being 1/16 inch. Each puck has a generally cylindrical bore 13 which is extended between the first and second faces. The bore 13 is located at the center of the puck. Preferably, the diameters of the tossing pucks 10 are substantially equal to one another and ideally, the diameter of each of the tossing pucks 10 is greater than 4¾ inches. Ideally the diameter of the tossing pucks is about 5⅛ inches. Ideally, the diameter of the target puck 15 is substantially equal to the tossing pucks about 5 1/8 inches. Each puck has a thickness defined between the first and second faces of the puck. Preferably, the thickness of the tossing pucks 10 is substantially equal to one another. The thickness of the target puck 15 is substantially equal to the thickness of the tossing pucks 10 . Ideally, the thickness of each puck is greater than ¾ inch and ideally 1⅛ inches. FIG. 1 shows the tactile indicia and concentric rings 14 that are elevated off of the surface about 0.006 to provide increased tactile function. FIG. 4 shows the method of play scoring positions of said tossing puck 10 in relation to said target puck 15 for various desired point values, displaying said fully supported and partially supported positions.
DETAILED DESCRIPTION OF THE INVENTION
[0033] In view of the foregoing disadvantages inherent in the known types of devices for playing horseshoe and bocce-ball games now present in the prior art, the present invention provides a new bounce-landing puck toss game device wherein the same can be utilized for playing a new puck throwing game with a new method of play not disclosed in combination or separately thereof in other patents.
[0034] One embodiment of the game of this invention is the apparatus of tossing pucks and one target puck, so constructed of the desirable weight, dimension, shape, and color-integrated plastic material which is enabling of the method of playas outlined in the claims. The most desirable and intended playing environments, which include beaches and parks, have commonplace and normally expected winds that adversely and negatively affect the tossing accuracy of the smaller, lighter, and less aerodynamic relevant prior-art apparatus. The negative effect of the wind in regards to accuracy of play of the previous art devices diminishes the practical challenge and entertainment value of the game. This adverse effect is successfully eliminated or substantially minimized by the weight, shape, and size of the pucks of this invention compared to prior art devices, thus providing a probability of tossing accuracy that is enabling of the intended and prescribed method of play and henceforth greatly increases the entertainment value.
[0035] Another embodiment of the apparatus of this invention is that the aforementioned construction provides a very durable structure that maintains form and color of the apparatus through the extreme hardships of the intended play of being tossed up to about 50 (fifty feet) on many different expected playing surfaces for hundreds or more of games.
[0036] The more important features of this invention have thus been broadly outlined, in order that the detailed description of the method of play 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.
[0037] 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.
[0038] 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.
[0039] 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.
[0040] It is therefore an object of the present invention to provide a new bounce-landing puck toss game device apparatus and method of play which has many of the advantages of the devices for playing horseshoe, bag toss, or bocce-ball type games mentioned heretofore and many novel features that result in a new bounce-landing puck toss game device which is not anticipated, rendered obvious, suggested, or even implied by any of the prior an devices for playing apparatus tossed at a target or bocce-ball games, either alone or in any combination thereof.
[0041] It is another object of the present invention to provide a new bounce-landing puck toss game device which may be easily and efficiently manufactured, and more specifically is constructed of injection moldable plastic material that accomplishes the specific desired playing characteristics that provide the necessary function of playas outlined by the previously stated method of play of this invention.
[0042] It is a further object of the present invention to provide a new bounce-landing puck toss game device which is of a durable and reliable construction.
[0043] An even further object of the present invention is to provide a new bounce-landing puck toss game device 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 bounce-landing puck toss game device economically available to the buying public.
[0044] Still yet another object of the present invention is to provide a new bounce-landing puck toss game device 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.
[0045] Still another object of the present invention is to provide a new bounce-landing puck toss game device for playing a puck throwing game with a method of play not probable or practical to achieve with normal prior art horseshoe, bag toss or bocce-ball type game apparatus.
[0046] Yet another object of the present invention is to provide a new bounce landing puck toss game device which includes a plurality of pucks, including a number of tossing pucks and a target puck. Each puck has a center, generally circular first and second faces, and a perimeter side edge between the first and second faces of the puck. Each puck has a generally cylindrical bore extending between its first and second faces.
[0047] Still yet another object of the present invention is to provide a new bounce-landing puck toss game device that is best played on sand or grass lawn, but may be played on many other types of ground surface.
[0048] These characteristics, 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 made to the accompanying drawings and descriptive matter in which the preferred embodiments of the invention are illustrated.
[0049] The best method for carrying out this invention is to utilize the services of those skilled in the arts of plastics injection molding to construct the apparatus in accordance with the relevant details of this invention. | A method of playing a puck-tossing game includes providing a target puck, a first plurality of tossing pucks of a first color, and a second plurality of tossing pucks of a second color. The target puck is tossed from a first tossing location, a distance of between approximately 10 feet to approximately 50 feet. At least one of the first plurality of tossing pucks is tossed toward the target puck in an effort to cause the at least one tossing puck from the first plurality of tossing pucks to land directly on top of the target puck. One of the second plurality of tossing pucks is tossed toward the target puck in an effort to cause the at least one tossing puck from the second plurality of tossing pucks to land on top of the target puck. | 0 |
FIELD OF THE INVENTION
This invention relates to sewing machines and is principally concerned with a presser mechanism which is adapted to cooperate with the feed mechanism of the machine in advancing a workpiece along a directed path of travel.
BACKGROUND OF THE INVENTION
It is generally well known in the art that it has proven difficult to sew a wrinkle-free seam when attaching rubber or elastic tape to the edge of a non-stretchable workpiece such as cotton or the like. The sewing operator had been faced with the perplexing problem of how to advance equal lengths of the workpiece and elastic between the presser foot and the feed mechanism without stretching the elastic. That is, the pressure on the foot which is necessary to advance the workpiece through the machine may cause the elastic to stretch thus resulting in certain amounts of wrinkling.
It may be suggested that one solution to the stretching of the elastic problem may be to reduce the pressure on the foot to a point whereat the stretching of the elastic is eliminated. However, the provision of such a slight pressure may prove to be insufficient for the foot to interreact with the feed mechanism in advancing the workpiece through the machine.
Further, when the presser foot passes over a seam or other thickened portion of the workpiece, the entirety of the foot may be lifted or tilted. As one skilled in the art may appreciate, when the presser foot bottom is removed or raised from contact with the workpiece it enhances the possibility of skipped stitches. These conditions are, of course, objectionable.
SUMMARY OF THE INVENTION
In an effort to eliminate the described problem of feeding the elastic beneath the pressure of the foot, there has been devised a presser foot assembly which is constructed so that a minimum of pressure is initially exerted against the elastic and workpiece; whereafter, once the elastic strip and workpiece are secured together an imperative heavier pressure is exerted so as to efficiently and effectively advance the sewn article through the machine.
The presser foot assembly of this invention includes a first presser foot section which is of very light construction and is substantially devoid of any material stretching action and a second presser foot section which is independently arranged directly behind and in line with the first presser foot section and is flexibly mounted relative thereto. The tandemly mounted presser foot sections are attached to a support body which may be carried at one end of a resiliently biased presser arm. The second presser foot section is adapted to receive the direct or full pressure of the presser arm while the other section is urged toward the workpiece under a lesser pressure. Thus, the workpiece as it travels along its directed path of travel is subjected to a plurality of different pressures.
Applicants, having recognized that it was necessary to independently mount the presser foot sections so that a plurality of pressures could be applied to the workpiece, recognized that, when properly mounted, the first presser foot section could impart a work feeding motion to the workpiece. In this regard, applicants proceeded to derive suitable means for achieving this purpose. Accordingly the present invention provides means for controlling the magnitude of the pressures applied against the presser foot sections.
Accordingly, it is a principal object of this invention to provide a presser mechanism having means which enable sewing of a wrinkle-free seam comprised of elastic and some non-stretchable workpiece.
Another object of this invention is to provide a presser mechanism having means adapted to exert a plurality of pressures upon the workpiece as it is advanced along its directed path of travel.
A further object of this invention is to provide a multi-pressure presser mechanism which makes it possible to substantially reduce any holding back of an elongated strip while at the same time effectively advancing the workpiece through the machine.
With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claimed subject matter and the several views illustrated in the accompanying drawings in which:
FIG. 1 is a side elevational view, partly in section, of the presser mechanism and associated parts of the sewing machine;
FIG. 2 is a view of the presser foot assembly taken on line 2--2 of FIG. 1;
FIG. 3 is a view of the presser foot assembly taken along line 3--3 of FIG. 1; and
FIG. 4 is a disassembled perspective view of the presser foot assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings in which like reference numerals indicate like parts through the several views, it may be seen that there is illustrated in FIG. 1 a conventional sewing machine which is generally identified by reference numeral 10. The sewing machine may be of the overedge sewing type sold by Union Special Corporation under the designation 39500RF. Thus it is not necessary to describe within the framework of the present application all of the complex multiple mechanisms which are incorporated into such a machine. It should be understood, however, that the invention is adapted for performing on other types of machines as well. Suffice it to say that the machine 10 includes a frame 12 and a needle means 14 fastened to a needle carrier 16 which is supported for reciprocation by instrumentalities which are located in the frame 12 but not shown. The sewing needle 14 cooperates with other sewing instrumentalities (not shown) in the formation of stitches in a workpiece W (FIG. 3) which is supported at the stitching zone 18 by the usual work support means 20. The machine 10 is further provided with a differential feed mechanism generally indicated at 22 which is well known to one skilled in the art of sewing machine and thus no further time will be devoted thereto.
Referring to FIG. 1, there is shown a presser mechanism 24 which is the subject of the present patent application. The presser mechanism 24 may be attached or carried at one end of a presser arm 26 whose longitudinal axis extends parallel to the work support means 20. The presser arm 26 is fashioned at its other extremity with a pair of oppositely disposed ears 28 and 30 between which is secured a lug extremity 32 of a rock shaft 34. The rock shaft 34 may be operatively connected to a knee or foot lifter (not shown). The lifter may be shifted so as to rotate the rock shaft 34 which, through the lug extremity 32, will rotate the presser arm 26 counterclockwise as viewed in FIG. 1 whereby lifting the presser mechanism 24 from contact with the work support means 20. Thus, the rock shaft 34 forms a horizontal pivotal axis for the presser foot assembly 24. Fastening means 36 is secured by nut 38 to ear 28 and provides for horizontal rotation of the presser arm 26 thus forming a vertical axis pivot for the presser foot assembly or mechanism 24.
The presser mechanism 24 includes a mounting bracket 40 which is attached to one end of the presser arm 26 and includes a rearwardly and downwardly extending portion 42 as seen from the position of the operator. It will be seen from the illustration that the portion 42 of bracket 40 is bifurcated and provides for a solid top portion 44 and two depending spaced walls 46. The spaced walls 46 are provided with a plurality of apertures 41, 50 and 52. Accomodated in the void between the two walls 46 are two presser foot sections 54 and 56. It is worthy to note that the first presser foot section 54 is independently mounted with respect to the presser foot section 56. That is, the presser foot section 54 may be raised or lowered while having no effect on the other presser foot section and the converse is also true. So as to independently mount the first presser foot section 54 to the mounting bracket 40 there is provided a cantilever or member means 58 which is adapted for pivotal movement on a pin means 60. The pin means 60 may be received in the aperture designated 41.
As seen in FIG. 1, one arm 62 of cantilever 58 extends generally horizontal under the solid top portion 44 of the bracket or mounting means 40. Extending from the solid top portion 44 of bracket 40 is a struck up member means 64. The struck up member 64 may be formed with an opening or a bore 66 which, in turn, provides a housing for a resilient member 68 which, in the preferred embodiment, is a compression coil spring. The lower end of the spring 68 bears down against the arm 62 of lever 58 while the upper end of the spring impinges against a stop means 70. In order to facilitate adjustment of the magnitude of pressure exerted against the first presser foot section, the stop means 70 may be formed as a screw which may be threadably engaged with the bore 66 and be vertically adjustable therein so that, depending on the vertical position of the screw, the spring is able to apply more or less pressure against the lever 58. The first presser foot section 54 is, therefore, not only independently movable relative the second presser foot section 56, but the pressure of the first presser foot section is also independently or individually adjustable. The spring 68 and associated mechanism serve to bias the other arm 71 of the lever 58 in a downward direction. The arm 71 slopes downwardly from the arm 62 of lever 58 and is pivotally connected at its extreme lower end to a presser foot sole 72 by any suitable means which are known in the art such as flat spring and screw means 74 and 76, respectively.
It should be noted that the major portion of the presser foot sole 72 extends forward of the stitching zone as seen by the operator. In addition, in view of the depicted way of mounting the presser foot section the pressure of the presser arm is prevented from acting directly on the sole plate 72 and only the auxiliary spring means 68 acts to urge the presser foot sole 72 downwardly during the normal operation of the sewing machine. Since the moving parts of the first presser foot section 54 have a very low mass and are not subject to the pressures exerted by the presser arm, a minimum of inertia forces will be developed and the presser foot sole 72 will follow the movements of the feed mechanism 22 with a minimum of overthrow.
As can be seen in FIGS. 1 through 4, the presser foot sole 72 may be provided with a strip guide means 78 which can be mounted on the toe portion 80 of the sole 72. Extending up the toe portion and along the undersurface of the sole 72 is a channel 82. The channel may be of a depth slightly greater than the thickness of the strip like material M (FIG. 1) which is to be secured to the workpiece. This channel in the presser foot section provides guide walls 84 and 86 which may aid in positioning the elongated strip for presentation to the stitch forming instrumentality.
When the presser mechanism 24 is lifted clear of the work support 20, the downward movement of the first presser foot section 54 under the influence of spring 68 will be limited by engagement of arm 62 with a pin 86 received in apertures 50, which pin thus constitutes a stop means 88. On the otherhand, and as may be best seen in FIG. 1, the location of the stop means 88 is such that it allows a limited degree of downward movement of the lever when the presser mechanism is in its operative position so as to not interfere with the first presser foot section cooperating with the feed mechanism in advancing the workpiece along a directed path of travel.
Also visible in FIG. 1, is a presser spring plunger 90 having provided at one end a bifurcated head 92 which is adapted to straddle the presser arm 26 and at the other end may be provided with a lock and cap assembly 94. Telescopically arranged intermediate the ends of the plunger 90 is a pressure adjusting screw 96 which, in turn, may be threadably received by a presser foot release bushing 98. The presser foot release bushing 98 is received within a bore 100 formed in the frame 12 of the machine. The adjusting screw 96 may be provided with a recessed bore 102 into which is inserted one end of a main presser spring 104. The other end of the presser spring 104 impinges against the bifurcated head of the plunger 90 and is adapted to apply a downwardly directed force against the presser arm 26 when the presser foot release bushing is in its operative position.
The second presser foot section 56 includes a presser foot sole 106 having an upstruck portion means 108 adapted for pivotal connection, by means of a transverse pin means 107 which is received in the aperture 52 in the mounting bracket 40. As shown in FIG. 1, the presser foot sole 106 has its front end chamfered as at 109 to facilitate mounting of the foot as closely proximate to the first presser foot section as possible. In addition, it is worthy to note that the presser foot sole 106 is colinearly aligned with the presser foot section 54. However, in the preferred embodiment, the entire second presser foot section 56 is disposed rearward of the stitching zone as viewed by the operator. Not like with the first presser foot section 56, the heavy or full pressure of the spring 104 is imparted to the second presser foot section 56 whereby allowing it to cooperate with the feed advancing means in its normal manner. As is apparent, since the second presser foot section engages the elastic only after it has been secured to the nonstretchable workpiece the operator need not worry about any stretching of the elastic strip and, therefore, the operator can impart the imperative heavy pressure required for advancing the workpiece through the machine.
With further reference to FIG. 1, it will be seen that a "Teflon" type strip 110 may be fixed in the channel 82. As is apparent, the "Teflon" strip should aid in the objective of applying little or no tension to the elastic strip by helping to reduce the friction as it is fed to the sewing instrumentalities. The "Teflon" strip may be cemented or otherwise affixed in the channel 82.
OPERATION OF THE DEVICE
In operation, the pressure spring 68 exerts a resilient yielding force on the lever 58 thus urging the first pressure foot section 54 toward the work supporting member of the machine. At the same time, the pressure spring 104 is exerting the heavier pressure against the arm 26 thus urging the second presser foot section toward the work support means of the machine. However, in view of their independence, the main pressure spring 104 is prevented or precluded from acting directly on the first pressure foot section. As a consequence, during the normal operation of the sewing machine the workpiece W, as it passes along its direct path of travel, is subjected to a plurality of varying pressures. That is, with the preferred embodiment, the elastic strip and the workpiece are first advanced under the influence of the light pressure exerted on the workpiece by the first presser foot section and after the pieces are secured they are then subject to the heavier pressure of the second presser foot section. In this manner the operator may be able to utilize one foot for feeding equal lengths of work to the stitching zone under both a light resilient pressure thus preventing the elastic from stretching and then subjecting the workpiece to the imperative heavy pressure so as to assure effective and efficient feeding of the workpiece through the machine.
When a cross seam or the like is encountered the individuality of the present invention may prove beneficial in aiding with the formation of stitches. That is, the separate mounting of the presser foot sections will allow the first presser foot section to raise independently of the second presser foot section. Accordingly, the first presser foot section is effective to maintain the raised or cross seam portion of the workpiece against the work support while the second presser foot section is effective to maintain the lower or single ply workpiece against the work support whereby insuring that the material may be stripped from the needle thus aiding the stitching mechanism in the formation of stitches.
In addition to all of the above mentioned advantages, the presser mechanism of this invention may further allow the first presser foot section to operate in a work feeding direction during the sewing cycle. The work feeding movement exerted by the first presser foot section 54 on the workpiece is believed to result from the fact that during the rise of the feed mechanism at the onset of the feeding stroke, the arm 58 being hinged in such a relation to the mounting means 40 will move the sole 72 on an arcuate path about the hinged connection 60 so that it moves both upwardly and a small increment forwardly in the direction of the operator. In view of the fact that the workpiece is secured by the stitching mechanism rearward of the presser foot section the material cannot be pushed forwardly toward the operator. However, this increment of the presser foot movement toward the operator is reversed during the terminal portion of the feed stroke thus allowing the presser foot sole 72 to act in concomitantly advancing the workpiece in the direction of feed.
Thus it is apparent that there has been provided, in accordance with the invention, a presser mechanism for sewing machines that fully satisfies the objects, aims, and advantages set forth above. While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications, and variations as fall within the spirit and broad scope of the claims. | This invention relates to a presser mechanism for sewing machines which includes a pair of independently tandemly mounted presser foot soles arranged to cooperate with the feed mechanism of the machine in advancing the workpiece along a directed path of travel. Different selectively variable pressures may be applied to the presser foot soles such that both a firm heavy pressure and a resilient lesser pressure is applied to the workpiece as it travels along its directed path of travel. | 3 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a non-provisional application of provisional application Serial No. 60/423,481 filed Nov. 4, 2002.
BACKGROUND OF THE DISCLOSURE
[0002] 1. Field of the Invention
[0003] The present invention relates generally to telecommunications services and, more particularly, to a global distributed services control platform for rapid delivery of services to service operators and subscribers.
[0004] 2. Background
[0005] With advent of the Internet a variety of new telecommunications services can be provided to end-users through application servers spread across the globe. The Internet, traditionally used for data communication applications, is increasingly being used for telephony and telecommunications services. With the modern convergence of voice and data networks, traditional telecom service providers and operators that are tied to legacy environments and legacy services are required to provide new services rapidly and economically. However, in order to provide new services or features to subscribers, telecommunications service operators and service providers typically would require additional equipment such as network bridges and new software to implement the new services or features. This is not a practical solution as each new service or feature involves additional higher cost and time. An alternative approach for a traditional service operator to offer new services to its subscribers is to cooperate with other service operators who can provide the new services or features. For illustration, consider a prior art scenario shown in FIG. 1. Service operator-A 100 provides a certain service to subscribers 110 via network-A 120 , and service operator-B 130 provides a different service to subscribers 150 via network-A 140 . The media and protocols used over the networks A and B could be quite different and incompatible. For example, service operator-A could be a wireless phone service operator for subscribers with indoor wireless communication devices such as PDA (Personal Digital Assistant), Bluetooth devices, and WiFi devices, and service operator-B could be Internet service provider with subscribers using laptops and PCs. If now, the service operator-A 100 needs to provide to its subscribers some of the services provided by service operator-B 130 , then a bridge between service operators A and B through network-C 160 needs to be created. In general, it is possible that the communication medium and protocol used over network-C 160 is different from those used over networks A and B ( 120 and 140 ). The bridging between service operators A and B ( 100 and 130 ) may also require suitable network interfaces (e.g., network bridge 101 ) to be newly installed and also development of new protocol bridging software (e.g., 102 ). Also, the providing of value added services by service operator-B 130 to service operator-A 100 may involve external application servers 170 that can communicate via network-C 160 . Thus, providing newer services to subscribers by service operator-A involves additional cost and time. Moreover, if service operator-A 100 wants to provide its subscribers other value added features by utilizing the services from other service operators then for each service operator providing a service, service operator-A 100 will incur additional cost for the network bridging interface (such as 101 ) and protocol software (such as 102 ). Such a solution is therefore not attractive in the current telecom scenario wherein there is an ever-increasing demand for new features and services. Therefore, there is now a need for a common communications services platform that can provide communication services to a variety of service operators irrespective of the network media and protocols they use. Such a global services platform is described in the present invention.
[0006] U.S. patent application publication Ser. No. 2002/0,052,754 A1 pertains to a convergent communications platform and method for mobile and electronic commerce in a heterogeneous network environment. Specifically, the invention relates to a convergent communications system that provides mobile and electronic commerce and communication services through existing communication switches without specific hardware located at those switches. An embodiment of the invention is a convergent communication system that resides in a centralized location. An aspect of the invention involves apparatus and method for providing pre-paid roaming communication services via a plurality of networks. Other aspects of the invention include methods of providing customer care services, recharging a pre-paid account, and settling a pre-paid transaction to a plurality of providers in a convergent communications environment. Even though the invention involves convergence of communication means to provide electronics commerce, it does not involve distributed control of services in a geographically distributed platform with the use of service monitors and program units such a described in our invention.
[0007] A service architecture for the rapid development of next generation telephony services that overcome the limitations of the current closed PSTN architecture and service model is described in U.S. patent application publication Ser. No. 2001/0,028,654 A1. Services in this architecture are provided by multiple cooperating distributed service providers. The invention basically involves a method and system for activating additional services from one or more independent service providers whiles telephone communication is being established or is already in progress between a calling party and a called party. In comparison, our invention involves a generalized services system with a plurality of service control nodes and service monitors.
[0008] U.S. patent application publication Ser. No. 2002/0,055,995 A1 describes a global service management system for use in an advanced intelligent network. The system is adapted to communicate with two or more network element managers servicing SCPs (Service Control Points) and operating pursuant to different protocols. The invention is aimed at solving the problem of protocol disparity among network element managers of different SCPs in an advanced intelligent network. Even though the problem of protocol disparity is addressed like in our invention, this invention does not involve service monitors with distributed service control nodes.
[0009] U.S. patent application publication Ser. No. 2001/0,013,001 A1 describes a web-based platform for interactive voice response (IVR). The speech synthesizer, grammar generator, speech recognizer and other elements of the platform may be operated by an Internet service provider, thereby allowing the general Internet population to create interactive voice response applications without acquiring their own IVR equipment. While the invention embodies a solution for providing IVR services to users without IVR equipment, it does not involve convergence of different communication services at a common platform as in our invention.
[0010] U.S. Pat. No. 6,289,201 B1 pertains to a communication system and method to enable service management in a global network environment including independent virtual networks. Specifically, this invention relates to a method and system for multi-layer service management in a satellite communication system. Distributed services management is achieved in this invention by way of satellite communications. While the invention involves a distributed application platform for building and executing network wide applications it does not pertain to providing services to existing service operators through a convergent communications platform as in our invention.
SUMMARY OF THE INVENTION
[0011] These shortcomings and other limitations and deficiencies are obviated in accordance with the present invention by a common communications services platform system, and concomitant methodology, provides communication services to a variety of service operators irrespective of the network media and protocols utilized.
[0012] In accordance with a broad system aspect of the present invention, a convergent service control platform for provisioning a communications service as requested by a service operator for a subscriber served by the operator includes: (1) a plurality of geographically-dispersed convergent services nodes, one of the services nodes serving the service operator; (b) a communications network connected to the nodes; and (c) a database, connected to the communications network, containing information about the service operator, the subscriber, and the communications service provisioned by the platform, the database storing information for at least one of the service nodes to configure the communications service provisioned by the platform.
[0013] Broad method aspects of the present invention are commensurate with the aforementioned broad system aspects.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The teachings of the present invention can be readily understood by considering the following detailed description in conjunction with the accompanying drawings, in which:
[0015] [0015]FIG. 1 is a high-level block diagram of a prior art system to provide additional customer services;
[0016] [0016]FIG. 2 is a high-level block diagram of a distributed convergent services platform in accordance with the present invention to provide new services and features to subscribers;
[0017] [0017]FIG. 3 is a high-level block diagram depicting the components of a convergent service node;
[0018] [0018]FIG. 4 depicts exemplary service transaction records for the node database of FIG. 3;
[0019] [0019]FIG. 5 depicts exemplary service records stored in the central database of FIG. 2;
[0020] [0020]FIG. 6 depicts exemplary service profile records stored in the central database of FIG. 2;
[0021] [0021]FIG. 7 depicts exemplary service monitors records stored in the service monitor of FIG. 3;
[0022] [0022]FIG. 8 depicts a flow diagram showing the service creation process for the distributed convergent service control platform of FIG. 2;
[0023] [0023]FIG. 9 depicts a relational diagram of an instance of providing service through the platform of FIG. 2;
[0024] [0024]FIG. 10 depicts a flow diagram showing the providing of service through the distributed convergent service control platform of FIG. 2;
[0025] [0025]FIG. 11A illustrates the process of copying convergent service pack information by a convergent service node;
[0026] [0026]FIG. 11B illustrates the technique for synchronizing two convergent service nodes and the central database of FIG. 2 with the convergent service pack information with respect to discrete points of time.
[0027] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures.
DETAILED DESCRIPTION
[0028] A preferred embodiment of the present invention is a convergent service control platform shown schematically in FIG. 2. The convergent service control platform 200 comprises a plurality of convergent service nodes (CSNs) ( 205 - 1 . . . 205 -N, collectively 205 ) that are capable of communicating with each other through a high-speed communications network 215 . In practice, convergent service nodes 205 are located at geographically different locations spread across the world to provide convenient short distance connectivity for service operators (e.g., 225 and 230 ). The convergent service nodes 205 are also capable of communication with each other via the Internet, PSTN, SS7/C7, wireless network and other networks ( 220 ). Also, the convergent service nodes ( 205 ) can communicate with external application servers 235 via the network cloud 220 comprising the Internet, PSTN, SS7/C7, wireless network and other types of networks. A service operator ( 225 , 230 ) that requires services provided through the convergent services control platform 200 is linked preferably to the closest CSN via a suitable communication bridge in the node (e.g., node 205 - 1 , discussed below). With the link thus established, a service operator can be provided a variety of new services by the convergent service control platform 200 by utilizing application servers within any CSN of the platform or application servers located at any external site accessible by the platform. The convergent service control platform includes a central database 210 that contains information about service operators and subscribers, and services that can be provided by the platform. Profiles of service operators and subscribers are stored in the database 210 . While the database 210 has been shown in FIG. 2 as a single entity located in one place, it can in general be distributed over memories of computers located at different geographical locations, but data consistency in maintained by avoiding multiple copies of the same data.
[0029] A schematic representation of a convergent service node 300 is shown in FIG. 3. The major components of a CSN include a set of network bridges 305 , an event/message router 310 , a set of local application servers 315 , service monitors 320 , a node database 330 , and a network 325 connecting the above-mentioned entities. The network bridges 305 are used to interface with service operators (e.g., 335 and 340 ), network 215 of the convergent service control platform 200 , external application severs 235 , and network cloud 220 including the Internet, PSTN, SS7/C7, wireless and other networks. By way of example and not limitation, typical bridges include TCP bridge/adapter, SMTP bridge, PSTN bridge, CAS/ISDN signaler, PSTN/IP bridge, SMPP bridge/gateway, UCP bridge/gateway, HTTP bridge, and SIP signaler that are well known to those skilled in the art. Communication with external entities takes place through the network bridges 305 . Service requests sent by service operators (e.g., 335 and 340 ) are received by the event/message router 310 via the network bridges 305 through the local network 325 . For convenience and efficiency of operation, the communication among the different entities of a CSN 300 takes place through a common format and language such as for example the XML (Extensible Mark-up Language). The bridges 305 convert service requests and other information received from service operators into the common format and language before sending them to the event/message router. The local application servers 315 hold program units that perform specific tasks. Providing a service in response to a service request generally involves one or more program units to function in a cooperative manner. Service Monitors 320 are special program units that coordinate and manage all program units working together to provide a service. Information about services necessary for the functioning of the program units and service monitors and transactions regarding services provided are stored in the node database 330 . Much of the information in the node database 330 is created by copying the relevant records from the central database 210 which are described later. Data consistency between the central database 210 and the node database 330 is maintained by periodic synchronization. While the central database 210 provides a unified storage for data related to all services and service operators of the platform 200 , the copied portions of data in the node database 330 are useful for fast retrieval locally and usage during the time a service is provided. Another component of the node database 330 includes the service transaction records as exemplified in FIG. 4. Relevant details of node database 330 and central database 210 are described now.
[0030] The rows and columns of the databases described herein represent records and fields thereof, respectively. In the described embodiments, the databases are used in a relational arrangement, as is known in the art, so that the databases relate to one another by way of fields that store common data. It is to be noted that while the following description refers to specific individual databases, formats, records, and fields, those skilled in the art will readily appreciate that various modifications and substitutions may be made thereto without departing from the spirit and scope of the present invention.
[0031] Referring now to FIG. 4 an embodiment of node database 330 is shown with service transaction records depicted in detail. For exemplary purposes, two records R 1 and R 2 are shown. Field 400 stores a transaction identifier that is associated with and that uniquely identifies a usage of a service by a subscriber. Fields 410 , 420 , and 430 are used to store the service operator identifier, service identifier, and subscriber identifier respectively. The numbers of digits in the fields 400 - 430 are shown only for exemplary purpose and can be fixed depending on the practical requirements of an implementation of the system. The date of transaction stored in field 440 in conjunction with transaction identifier uniquely identifies a transaction. Field 450 stores a pointer to the file that stores the details of the transaction. The keyword ‘Path’ indicated in field 450 refers to the server and directory path in the server where the transaction details file (e.g., 1234.TRD) can be located. A transaction details file contains relevant information about the service based on which subscriber service reports and bills can be produced.
[0032] As already mentioned, the node database 330 comprises information copied from the central database 210 , and as such, the following description with regard to central database 210 with FIGS. 5, 6, and 7 also applies to the node database 330 .
[0033] Referring next to FIG. 5, an embodiment of central database 210 is shown with service records depicted in detail. Service records of database 210 store data relating to one or more services. One record (row) is maintained for each service. For exemplary purposes, two records R 3 and R 4 are shown. Field 500 stores a service operator identifier that uniquely identifies a service operator. Field 510 is used to store a service identifier that identifies a service being offered to the subscribers of the service operator. Field 520 stores identifiers of subscribers that have subscribed to the service indicated in field 510 . Field 530 stores the name of the service monitor used to offer the service. More details of service monitors are given in service monitor records that will be described later with reference to FIG. 7.
[0034] Referring next to FIG. 6, an embodiment of central database 210 is shown with service profile records depicted in detail. For exemplary purposes, two records R 5 and R 6 are shown. A subscriber identifier is stored in field 600 and a pointer to the file storing the subscriber's profile is given in field 610 . The keyword ‘Path’ indicated in the field 610 refers to the server and directory path in the server where the subscriber profile file (e.g., 112.PRF) can be located. The information contained in the subscriber profile file is useful for providing a service to the subscriber and optimizing resources and costs involved in providing the service.
[0035] Referring next to FIG. 7, an embodiment of central database 210 is shown with service monitor records depicted in detail. For exemplary purposes, two records R 7 and R 8 are shown. A service monitor identifier is stored in field 700 . Field 710 stores identifiers of program units that are invoked by the service monitor indicated in field 700 and the respective CSNs where the program units are located are stored in field 720 . A service monitor may invoke program units residing in servers external to the platform 200 , and such external application program units are identified in field 730 with the respective servers indicated in field 740 . It is noted that while alphanumeric abbreviations are indicated in fields 700 - 740 , in practice, identifiers involving file path names and Internet URLs are generally used.
Service Creation
[0036] A schematic flow diagram showing the service creation process is shown in FIG. 8, including the following processes.
[0037] Process 805 : A service on the platform 200 is created based on the specifications given by a service operator. Basically, a service operator specifies service requirements, subscriber profiles and other information to the platform operator. In order to simplify service specification and implementation, a set of service templates involving basic service functions are provided by the platform operator. Also, a suitable format and language is defined for service requirements specification. For example, XML service functions templates could be provided and other non-template specification would be required to be provided using XML.
[0038] Process 810 : Based on the service requirements, the platform operator decides the best concurrent service node(s) that can provide the required service to the service operator. It is possible that depending on the service constraints and features, more than one CSN may be configured to provide the service. For example, depending on the time of providing a service through the platform 200 , it may be economically beneficial to have the service functions performed in CSNs located in different time zones across the globe. In such a case, a service monitor is programmed to switch to appropriate program units in other CSNs.
[0039] Process 815 : Communication links between the service operator's existing set-up and the platform 200 through suitable interface hardware and bridges in the CSN(s) are established.
[0040] Process 820 : Based on the service specifications provided by the service operator, an appropriate service monitor and the required program units are defined, developed and installed on the servers in the CSN(s). If the service specifications are already in the known format (e.g., XML) and service templates have been used, then it is possible that many of the installation processes for service monitor and program units could be performed through automated program development processes.
[0041] Process 825 : The central database 210 is updated with the service information including service monitor and subscriber details such as shown in FIGS. 5, 6, and 7 .
[0042] Process 830 : With all the constituent modules of a service installed on the servers in CSN(s), a service is deployed after linking all the constituent operational units including external application programs if any.
Platform Operation
[0043] [0043]FIG. 9 depicts a relational diagram 900 useful in understanding an embodiment of the invention. Specifically, the relational diagram 900 depicts an instance of providing service through the platform 200 . Also, the diagram 900 is helpful in understanding the temporal interactions among the different functional elements depicted in FIG. 2. The interactions of FIG. 9 are indicated along with the description of FIG. 10 that depicts a flow diagram showing the providing of service through the platform 200 , involving the following processes.
[0044] Process 1005 : A subscriber invokes 901 a service that involves some functions from the service control platform. The service operator finds from the requested service that to provide that service some functions or features need to be performed with the help of the convergent services control platform 200 . Accordingly, the service operator sends 902 a service request to the convergent service node 205 - 1 in the required service request format.
[0045] Process 1010 : The service request is received through a bridge in the CSN 205 - 1 and routed to the appropriate service monitor 960 . The service monitor then accesses 903 the node database 330 , and central database 210 , if required, and gets 904 the relevant service and subscriber related information. Process 1015 : Service monitor 960 invokes 905 program units in the local application servers 315 of the CSN 205 - 1 and sends 906 service requests to other CSNs (e.g., 205 - 2 , 205 - 3 ), if required.
[0046] Process 1020 : Program units in CSN(s) perform the required service functions. It is possible that some service functions may have to be completed by utilizing external application servers (e.g., 940 , 950 ). In that case, monitor programs within some CSNs (e.g., 205 - 1 , 205 - 3 ) send 907 service requests to external application servers and receive 908 the results.
[0047] Process 1025 : The service monitor 960 receives 909 service function results from program units within CSN 205 - 1 and other CSN(s) (e.g., 205 - 2 , 205 - 3 ), if any.
[0048] Process 1030 : The service monitor 960 consolidates service function results and sends 910 them to the service operator 930 . The subscriber 920 then receives 911 the requested service through the service operator 930 .
[0049] A distinguishing embodiment of the invention is the method of keeping the information about the subscriber, service and the particular category of service as a package within the central database. A given communication service can have different sub-categories called products. For example, an SMS service could have two products—product 1 with limited number of short messages per day and product 2 with no limit on the number of SMS messages. In the central database, the information about the subscriber, service and the product are logically considered as a group—Convergent Service Pack (CSP). A subscriber may utilize the service through any convergent service node of the system, but still the context of service is maintained the same by copying the CSP information. FIG. 11-A illustrates the process of copying the CSP information by a CSN. The subscriber 1100 utilizes the service through the service operator site 1 ( 1110 ) and CSN 205 - 1 . During this time, the subscriber information (SB), service information (SR) and the product information (PR) as a group CSP 1130 is copied as an instance CSP 1140 in the node database of CSN 205 - 1 . If allowed, the subscriber may change some of the information in the CSP 1140 . After the subscriber has completed utilizing the service, the CSP 1130 is later updated in the central database 210 . It may be noted that at this stage the CSN 205 - 2 does not have any information about the subscriber and the service. FIG. 11-B illustrates the technique for synchronizing two convergent service nodes and the central database of FIG. 2 with the convergent service pack information with respect to discrete points of time. Referring to FIG. 11-B, suppose at a later time the subscriber 1100 requests for the service through a different service operator site 2 ( 1120 ). The corresponding CSN 205 - 2 then gets the CSP information into its node database as an instance CSP 1150 . Because the CSP information is thus copied, the subscriber gets the same service context as earlier. Again, any changes to the CSP 1150 during this service utilization will be updated in the central database 210 at a later time when the subscriber has completed utilizing the service through CSN 205 - 2 . Thus the node databases in the CSNs and the central database 210 are synchronized with reference to their data at discrete points of time.
Application Example
[0050] Consider a cell-phone user getting phone service from a regular cellular service provider. If the cellular service provider now wants to provide teleconferencing service, then a teleconferencing application interface is created with the convergent service control platform. Then, the cell-phone user is directed by the service provider to a convergent service node for utilizing the teleconferencing service. The user then can create his/her profile that contains among other details, contact information about teleconference participants. At a later point of time, the user can initiate a teleconference through any CSN of the system. The CSN then extracts the participants' telephone numbers from the profile of the user stored in the central database and initiates a teleconference service monitor in the CSN. The teleconference service monitor then coordinates the conduction of the teleconference among the chosen members.
[0051] Although the embodiments of the present invention have been shown and described in detail herein, those skilled in the art can readily devise many other varied embodiments that still incorporate these teachings. Thus, the previous description merely illustrates the principles of the invention. It will thus be appreciated that those with ordinary skill in the art will be able to devise various arrangements, which although not explicitly described or shown herein, embody principles of the invention and are included within its spirit and cope. Furthermore, all examples and conditional language recited herein are principally intended expressly to be only for pedagogical purposes to aid the reader in understanding the principles of the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future, that is, any elements developed that perform the function, regardless of structure.
[0052] In addition, it will be appreciated by those with ordinary skill in the art that the block diagrams herein represent conceptual views of illustrative circuitry, equipment, and systems embodying the principles of the invention. | A common communications services platform, and concomitant methodology, provides communication services to a variety of service operators irrespective of the network media and protocols utilized. The platform is composed of: (1) a plurality of geographically-dispersed convergent services nodes, one of the services nodes serving the service operator; (2) a communications network connected to the nodes; and (3) a database, connected to the communications network, containing information about the service operator, the subscriber, and the communications service provisioned by the platform, the database storing information for at least one of the service nodes to configure the communications service provisioned by the platform. | 7 |
BACKGROUND OF THE INVENTION
(1) Field of the Invention
This invention relates to earth anchors and more particularly to anchor rods to which an anchor eye cap and an anchor member are affixed.
(2) Description of the Prior Art
It has been recognized that the corrosion of metal objects in the earth is largely an electrolysis process; therefore people have attempted to prevent the electrolysis by charging the metal object with electrical generators. Generally, this process is called "cathodic" protection. However, usually for short, small objects buried in the ground, such as anchors for guy wires, the only effort to protect them is to put a coating on them such as galvanization or paint. My prior U.S. Pat. No. 3,675,381 discloses electrically insulating the rod from the anchor and the surrounding soil.
However, even with the use of paint, galvanization, asphalt mastic or plastic tubing around the anchor rod to protect it from corrosion, as the anchor eye cap and bottom nut are secured to the anchor rod, the outer limits or ends of the rod coating are left unsealed. This results in corrosion to the anchor rod at this point.
SUMMARY OF THE INVENTION
(1) New and Different Function
I have solved the problem of preventing corrosion to anchor rods that occurs when anchor eye caps and bottom nuts are affixed to the anchor rod. I have accomplished this by recessing the anchor eye and bottom nut and filling this recess with water proofing material to seal the ends of the rod coating to the anchor eye and botton nut.
Thus, it may be seen that the total function is far greater than the sum of the individual functions of the rods, rod covers, recesses, etc.
(2) Objects of this Invention
An object of this invention is to provide permanent anchors.
Another object is to reduce corrosion on anchor rods.
Further objects are to achieve the above with a device that is sturdy, compact, durable, lightweight, simple, safe, efficient, versatile, ecologically compatible, energy conserving, and reliable, yet inexpensive and easy to manufacture, and install.
The specific nature of the invention, as well as other objects, uses, and advantages thereof, will clearly appear from the following description and from the accompanying drawing, the different views of which are not scale drawings.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a representation of an anchor and rod according to my invention attached to a utility pole.
FIG. 2 is an axial sectional view of an anchor, according to my invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Anchors are used for many purposes, one example of which is to attach guy wire 6 to pole 8. FIG. 1 shows such an installation where the guy is attached through anchor eye 16 on anchor rod 12 of an anchor.
Protective cover 10 surrounds the anchor rod 12. Eye cap 14 containing the eye 16 is secured over the top of the anchor rod 12. The eye 16 provides convenient, conventional means by which a tension member may be attached to the rod. Eye flange 18 on the bottom portion of the eye cap 14 telescopes over the rod 12 and also over the protective cover 10. The eye cap 14 is secured to the rod above eye flange 18. The cap is secured to rod 12 by external threads on top of the rod 12 and internal threads in the top of the eye cap 14.
Insulating material 20, such as asphalt, is placed in the recess which extends from open end 22 of the eye cap 14 and the threads. The material is in the cap before the rod 12 is secured to the cap 14. This results in insulating material 20 sealing the protective covering 10 from eye cap 14. Therefore, there is no corrosion problem at this point.
It will be understood that the protective cover 10 around the anchor rod may be a plastic sleeve or asphalt material covered by a plastic sleeve or the like. Therefore, it is highly desirable to have the flange on the eye cap extending over the top of the cover to contain the top or to protect the top from damage as well as to seal the top of the protective cover. It may be seen that with the insulating material 20, which is itself a sealant, there is a good seal formed at the top of the protective coating so that no moisture or other corrosive fluids can seep into a void between the protective covering and the rod. By filling the cap with a sealant material before it is applied to the rod, the sealant material will also form a lubricant as well as an insulation barrier between the threads of the cap 14 and the threads of the top of the rod 12.
Anchor member 24 is attached to the anchor rod 12 by bottom nut 26. The anchor 24 is an outward extending member which prevents axial movement of the anchor rod 12. Anchor members are well known to the art. Nut 26 is attached below the anchor member 24 and over the anchor rod 12. Nut flange 28 on the top portion of the bottom nut 26 telescopes over the rod 12 and protective covering 10. The flange 28 forms a recess between the nut and the rod cover forming the same structure and function as the recess within the eye cap. Nut 26 is secured to rod 12 by external threads on the bottom of the rod 12 and internal threads on the lower portion of the bottom nut 26, i.e., anchor member 24 has a hole through which the rod 12 extends. Washer 32 of electrical insulating material surrounds the rod 12 immediately below the anchor member 24. Nut 26 is secured to rod 12 below washer 32, securing rod 12 to anchor member 24.
Insulating material 20, such as asphalt, is placed in the recess extending between the open end 30 and the threads of the nut 26, as with the eye cap. This results in insulating material 20 sealing protective covering 10 from the bottom nut 26. Therefore, there is no corrosion problem at this point.
The embodiment shown and described above is only exemplary. I do not claim to have invented all the parts, elements or steps described. Various modifications can be made in the construction, material, arrangement, and operation, and still be within the scope of my invention. The limits of the invention and the bounds of the patent protection are measured by and defined in the following claims. The restrictive description and drawing of the specific example above do not point out what an infringement of this patent would be, but are to enable the reader to make and use the invention. | Anchor rods are protected against corrosion by inserting sealant within an anchor eye cap recess and bottom nut recess before fastening the eye and anchor member to the rod. Protective rod covering also is within the recesses. | 4 |
BACKGROUND OF INVENTION
The present invention is directed to damping mechanisms, and more particularly, to damping mechanisms for use with hinged covers of housings and other enclosures.
Electronic devices, such as printers, copiers, facsimile machines, scanners, CD players and the like typically include a body that provides structural integrity to the device. In order to provide access to the internal components of the device, the body typically includes an access opening that is protected by a movable cover. The cover is movable between an open position and a closed position such that the internal components of the device can be accessed through the access opening. The cover may be biased in either the open or closed position, and a detent mechanism may be used to maintain the cover in its non-biased position. Various mechanisms, such as springs, air/hydraulic piston assemblies, or gravity may be used to bias the cover in the open or closed positions. However, the biasing mechanisms may not provide for a smooth, controlled opening or closing motion of the access cover. Accordingly, there is a need for a damping mechanism that damps the motion of the cover of an electronic device.
SUMMARY OF THE INVENTION
The present invention is a damping mechanism which can be used to damp the movement of a cover of a housing, such an electronic device. The damping mechanism includes a cam having a generally curved cam surface that is shaped to engage a generally planar damping surface. The damping pad and cam cooperate to slow the opening or closing motion of the cover.
In a preferred embodiment, the invention is a damping mechanism for use with a housing having a body and a cover pivotably attached to the body, the cover being movable between an open position and a closed position. The damping mechanism includes a body engagement surface located on the body and a cover engagement surface located on the cover. One of the body engagement surface or the cover engagement surface includes a generally planar damping pad and the other of the body engagement surface or the cover engagement surface includes a cam having a generally curved cam surface. The cam surface is shaped and positioned to engage the damping pad such that the damping pad and the cam cooperate to damp the movement of the cover when the cover pivots between the open and closed positions.
Accordingly, it is an object of the present invention to provide a damping mechanism for a cover of an electronic device that is robust and durable. Other objects and advantages of the present invention will be apparent from the following description and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an upper perspective view of a printer including one embodiment of the damping mechanism of the present invention, with the cover in the closed position;
FIG. 2 is an upper perspective view of the printer of FIG. 1, with the cover in the open position;
FIG. 3 is a lower perspective view of the damping mechanism of the printer of FIGS. 1 and 2;
FIG. 4 is an upper perspective view of the cover of the printer of FIG. 1;
FIG. 5 is an upper perspective view of the cover of FIG. 4, with the outer shell removed;
FIG. 6 is a side view the latch mechanism of the printer of FIG. 1, with the outer shell removed, the latch shown in the engaged position;
FIG. 7 is a side view of the latch mechanism of the printer of FIG. 1 with the outer shell removed and the latch shown in the disengaged position;
FIG. 8 is an detail perspective view showing an alternative mounting arrangement for the damping pad of the damping mechanism of the present invention; and
FIG. 9 is a side view of an embodiment of the damping mechanism of the present invention.
DETAILED DESCRIPTION
As shown in FIGS. 1 and 2, the damping mechanism 11 of the present invention may be used in a business machine, such as a printer or housing 10 having a body 12 . The body 12 includes an access opening 14 that is selectively covered by a cover 16 . The cover 16 is pivotably coupled to the body 12 by a hinge mechanism 18 . In this manner, the cover 16 is moveable between a closed position (FIG. 1) and an open position FIG. 2 ).
As best shown in FIG. 3, the cover 16 includes a cover engagement surface 70 . In the illustrated embodiment the cover engagement surface 70 is a cam 72 having a cam surface 74 that is generally curved in side view. The cam 72 can be made from a variety of materials, preferably plastics, such as high impact polystyrene. In the illustrated embodiment the cam 72 is integral with the cover 16 , and is generally shaped as a portion of a circle in top view. The body 12 includes a body engagement surface 76 that is shaped and located to engage the cover engagement surface 70 . Although FIG. 3 does not illustrate the body engagement surface 76 as being coupled to the body 12 , various mechanisms (such as adhesives, clamps, fasteners, interference fits, etc.) known to those of ordinary skill may be used, although a preferred manner for mounting the body engagement surface 76 to the body is illustrated and discussed below. In the illustrated embodiment the body engagement surface 76 is generally planar damping pad 78 , although other shapes of damping pads may be used. For example, the damping pad may be curved to match the curvature of the cover engagement surface. The damping pad 78 may be made from a variety of materials, but is preferably made of a resilient compressible material which provide high friction forces when the damping pad 78 engages the cam 72 . The damping pad 78 is preferably made of a thermal plastic elastomer, such as SANTOPRENE 101-55.
As shown in FIG. 4, the cover 16 includes an outer shell 46 and an inner shell 48 . A latch assembly 50 (FIG. 5) is located between the outer shell 46 and the inner shell 48 . The latch assembly 50 includes a handle 52 , an arm 54 and a catch 56 . The arm 54 is pivotably mounted to the inner shell 48 at pivot point 49 , and the catch 56 is aligned with an opening 58 in the inner shell. The upper end of the arm 54 is coupled to a latch spring 60 that extends between the inner shell 48 and the arm 54 . As shown in FIG. 4, the outer shell 46 of the cover 16 substantially covers the latch assembly 50 , and includes a indentation 63 to receive the handle 52 .
In order to lock the cover 16 in its closed position, the catch 56 extends through the opening 58 in the inner shell 48 and is received in a notch 64 in the front cover 66 of the body 12 (FIG. 6 ). When the catch 56 is received in the notch 64 (i.e., the latch assembly 50 is in its engaged position), the catch engages the top surface of notch 64 to maintain the cover 16 in its closed position. The latch assembly 50 is biased into its engaged position by the latch spring 60 . When it is desired to move the cover 16 to its open position, the handle 52 is pulled to move the latch assembly 50 to its release position (shown in FIG. 7 ), compressing the latch spring 60 . When the catch 56 is rotated clear of the notch 64 , the cover 16 moves to its open position and as biased by the torsion spring 42 .
As best shown in FIG. 3, the cover 16 includes a cover engagement surface 70 . In the illustrated embodiment the cover engagement surface 70 is a cam 72 having a cam surface 74 that is generally curved in side view. The cam 72 can be made from a variety of materials, preferably plastics, such as high impact polystyrene. In the illustrated embodiment the cam 72 is integral with the cover 16 , and is generally shaped as a portion of a circle in top view. The body 12 includes a body engagement surface 76 that is shaped and located to engage the cover engagement surface 70 . Although FIG. 3 does not illustrate the body engagement surface 76 as being coupled to the body 12 , various mechanisms (such as adhesives, clamps, fasteners, interference fits, etc.) known to those of ordinary skill may be used, although a preferred manner for mounting the body engagement surface 76 to the body is illustrated and discussed below. In the illustrated embodiment the body engagement surface 76 is generally planar damping pad 78 , although other shapes of damping pads may be used. For example, the damping pad may be curved to match the curvature of the cover engagement surface. The damping pad 78 may be made from a variety of materials, but is preferably made of a resilient compressible material which provide high friction forces when the damping pad 78 engages the cam 72 . The damping pad 78 is preferably made of a thermal plastic elastomer, such as Santoprene 101-55.
Once the latch assembly 50 is moved to its disengaged position, the cover 16 moves from its closed to its open position, as biased by the spring 42 . As the cover 16 moves from its closed to its open position, the cam surface 74 engages the damping pad 78 , and the frictional forces between the cam surface 74 and the pad 78 slow the opening movement of the cover 16 . As shown in FIGS. 8-9, the damping pad 78 is preferably mounted onto a leaf spring 81 formed by cantilevered arm 84 . In this manner, the leaf spring 81 biases the damping pad 78 against the cam 72 when the cam surface 74 first engages the damping pad 78 . Thus, when the cam surface 74 first engages the damping pad, there is a relatively high amount of friction between the cam surface and the damping pad 78 . However, as the cam 72 and damping pad 78 “compresses” the damping pad spring 81 (i.e., moves the cantilevered arm 84 radially outwardly), frictional forces between the cam 72 and the damping pad 78 are decreased. Thus, the damping forces of the damping mechanism 11 are highest when the cam 72 first engages the damping pad 78 . This is desirable because the torsion spring 42 exert its highest opening forces during the initial opening movement of the cover 16 , and therefore the strongest damping of the damping mechanism 11 corresponds to the strongest forces exerted by the torsion spring 42 . After the damping pad spring 81 is “compressed,” the friction forces between the damping pad 78 and the cam surface 74 result in a smooth, controlled opening motion of he access cover 16 .
A wide variety of shapes, materials and mounting orientations may be used or the cam 72 and the damping pad 78 without departing from the scope of the invention. Furthermore, a variety of biasing mechanisms, such as a standard coil spring, may be used in place of the leaf spring 81 to bias the damping pad 78 against the cam surface. Further alternately, the cam surface 74 may be spring biased against the damping pad 78 . In yet another alternate embodiment, the damping pad 72 is located on the cover 16 and the cam 72 is located on the body 12 . In this case the cam 72 is stationary as the damping pad 72 moves with the cover 16 during its opening or closing motion.
When the cover 16 is moved from its open position to the closed position, the cam surface 74 and damping pad 78 may frictionally engage each other to oppose the closing motion of the cover 16 . However, the frictional forces generated between the cam surface 74 and the damping pad 78 are relatively low compared to the biasing force of the torsion spring that must also be overcome to close the cover.
In a preferred embodiment, the damping mechanism 11 selectively damps the opening or closing motion of the cover 16 . As shown in FIG. 9, the cam 72 may include a protrusion portion 80 that extends radially outwardly from a recessed portion 82 of the cam. In this case, the cam surface 74 is located on the outer surface of the protrusion portion 80 . For example, the cam 72 may be generally shaped as a section of a circle in top view (such as a section extending for about 110° of a full circle). The protrusion portion 80 may protrude radially outwardly for about 30° of the full 110° of the cam 72 , and be located about 10° from a lower edge 83 of the cam. Thus, for example, if the cover 16 moves about 110° when it moves from its closed position to its open position, the cam surface 74 engages the damping pad 78 for about 30° of the total 110° of travel. In the illustrated embodiment, the first 10° of rotational travel of the cam 72 (indicated by section A of FIG. 9) is undamped, the next 30° of travel (indicated by section B) is damped by the cooperation between the damping pad 78 and the cam surface 74 , and the remaining 70° of travel (indicated by section C) is undamped.
The initial, undamped 10° of opening motion allows the cover 16 to quickly “spring” open to ensure that the catch 56 quickly clears the notch 64 when the latch mechanism 50 is moved to its disengaged position. The next 30° of opening motion of the cover 16 is damped, to provide a smooth, controlled opening motion of the cover 16 . Of course, as noted above, relatively high damping forces are applied when the cam 72 first engages the damping pad 78 . Finally, the remaining 60° of travel of the cover 16 is undamped because the force exerted by the torsion spring 42 at this portion of travel of the cover is relatively weak. In this manner, the cam 72 shown in FIG. 9 is shaped to provide different levels of damping as the cover 16 moves from the open position and the closed position to provide a smooth opening motion. Of course, the size and shape of the cam 72 or damping pad 78 may be varied to provide for a variety of damping profiles, as desired.
Having described the invention in detail and by reference to the preferred embodiments, it will be apparent that modifications and variations thereof are possible without departing from the scope of the invention. | A damping mechanism for use with a housing having a body and a cover pivotably attached to the body, the cover being movable between an open position and a closed position. The damping mechanism includes a body engagement surface located on the body and a cover engagement surface located on the cover. One of the body engagement surface or the cover engagement surface includes a generally planar damping pad and the other of the body engagement surface or the cover engagement surface includes a cam having a generally curved cam surface. The cam surface is shaped and positioned to engage the damping pad such that the damping pad and the cam cooperate to damp the movement of the cover when the cover pivots between the open and closed positions. | 8 |
PRIORITY
This application claims priority to U.S. Provisional Application No. 61/791,909, filed Mar. 15, 2013, and to PCT/US2014/029674, filed Mar. 14, 2014, each of which is hereby incorporated by reference in their entireties.
FIELD OF THE INVENTION
The invention relates to methods of making prodrug compounds useful against cancer. In one example, the invention relates to methods of making a prodrug comprising the thapsigargin derivative 8-O-(12-aminododecanoyl)-8-O-debutanoyl thapsigargin (12ADT) linked to the aspartic acid of a peptide having the sequence Asp-Glu*Glu*Glu*Glu, wherein at least one of the bonds designated with * is a gamma carboxy linkage, and having the formula of Formula 1:
as well as methods of making certain intermediates thereof. The invention also relates to the compounds and intermediates obtained by the processes herein set forth.
BACKGROUND OF THE INVENTION
A peptide prodrug compound identified as G-202, and comprising the thapsigargin derivative 8-O-(12-aminododecanoyl)-8-O-debutanoyl thapsigargin (12ADT) linked to the aspartic acid of a peptide having the sequence Asp-Glu*Glu*Glu*Glu, wherein at least one of the bonds designated with * is a gamma carboxy linkage and having the structural formula:
(Formula 1) has been set forth and described in U.S. Pat. Nos. 7,767,648 and 7,468,354, which are incorporated herein in their entireties. Injectable cancer compositions comprising G-202 and Methods and Compositions for Treating Hepatocellular Carcinoma using G-202 are also disclosed in U.S. Provisional Appln. Nos. 61/714,662 and, 61/693,273, which are incorporated herein in their entireties.
The major challenge for a process to produce G-202 is due to the lack of crystallinity of any of the intermediates or final active pharmaceutical ingredient (API). This precludes the use of crystallization for removal of impurities at any point in the synthesis. This constraint makes it essential that the reactions be highly efficient and generate little to no impurities. In addition, the lack of crystallinity increases the value of alternate purification processes such as aqueous extractions, polar/non-polar organic partitioning, precipitation, trituration and efficient chromatographic purification. This process disclosed herein successfully incorporates an effective synthetic strategy and all of these purification techniques to generate pure G-202.
SUMMARY OF THE INVENTION
In one aspect, the invention provides a method for making the compound of Formula I:
having the chemical name 8-O-(12-aminododecanoyl)-8-O-debutanoyl-thapsigargin) aspartate-γ-glutamate-γ-glutamate-γ-glutamate-glutamate OH, which comprises:
(a) modifying thapsigargin (Tg) (Formula 2)
to yield the compound 8-O-Debutanoyl-thapsigargin (DBTg) (Formula 3):
and (b) adding the compound Boc-12-AD (Formula 4) in the presence of dimethylaminopyridine (DMAP), diisopropylcarbodiimide (DIC) and CH 2 Cl 2 :
to yield Boc-12ADT (Formula 5):
and (c) deprotecting BOC-12ADT to yield 12-ADT (Formula 6):
and (d) combining 12-ADT with Boc-Asp-Glu(OtBu)-Glu(OtBu)-Glu(OtBu)-OtBu (Formula 7):
in the presence of ethyl-(dimethylaminopropyl)carbodiimide (EDC), diisopropylethylamine (iPr 2 NEt), hydroxybenzotriazole (HOBt), and dimethylformamide (DMF) to yield PG-202 (Formula 8):
and (e) reacting PG-202 to yield the compound Crude G-202 (Formula 9):
and (f) then converting Crude G-202 to the compound of Formula 1.
In another embodiment of the invention, there is provided a method of making the compound BOC-12-AD (Formula 4):
which comprises:
(i) reacting the compound 12-AD (Formula 10):
with methanol (MeOH) in the presence of acetyl chloride (AcCl) to yield the compound of Formula 11:
and (ii) reacting the compound of Formula 11 with di-(tert-butyl)dicarbonate (Boc 2 O) in the presence of 4-dimethylaminopyridine (DMAP) and a tertiary amine base R 3 N to yield the compound of Formula 12:
wherein the tertiary amine can be but is not limited to triethylamine (Et 3 N), diisopropylethylamine (iPr 2 NEt), or N-methylpiperidine, and (iii) reacting the compound of Formula 12 to produce the compound of Formula 4 (Boc-12-AD).
The invention is also directed to the novel compounds of Formula 1 through Formula 12, including variations and derivatives thereof, the compounds of Formula 1 through Formula 12, including variations and derivatives thereof, produced by the methods disclosed herein, and other compounds that may be produced or generated using the methods provided herein.
The invention is directed to these and other important ends, hereinafter described.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows a schematic drawing of the overall reaction to produce G-202.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Following long-standing patent law convention, the terms “a,” “an,” and “the” refer to “one or more” when used in this application, including the claims. Thus, for example, reference to “a subject” includes a plurality of subjects, unless the context clearly is to the contrary (e.g., a plurality of subjects), and so forth.
For the purposes of this specification and appended claims, unless otherwise indicated, all numbers expressing amounts, sizes, dimensions, proportions, shapes, formulations, parameters, percentages, parameters, quantities, characteristics, and other numerical values used in the specification and claims, are to be understood as being modified in all instances by the term “about” even though the term “about” may not expressly appear with the value, amount or range.
Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any machines, materials, and methods similar or equivalent to those described herein can be used to practice or test the present invention, the preferred machines, materials and methods are now described. All publications mentioned herein are cited for the purpose of describing and disclosing the cell lines, protocols, reagents and vectors which are reported in the publications and which might be used in connection with various embodiments of the invention. Nothing herein is to be construed as an admission that the invention is not entitled to antedate such disclosure by virtue of prior invention.
As used herein, the term “G-202” refers to 8-O-(12-aminododecanoyl)-8-O-debutanoyl-thapsigargin) aspartate-γ-glutamate-γ-glutamate-γ-glutamate-glutamate OH, having the chemical structure of Formula 1.
G-202 is a thapsigargin prodrug containing a cytotoxic analog of thapsigargin coupled to a masking peptide that inhibits its biologic activity until proteolytic cleavage at the tumor site. Thapsigargin itself is a natural product that is chemically modified to 8-O-(12-aminododecanoyl)-8-O-debutanoyl-thapsigargin) (12ADT). This thapsigargin analog is coupled to the beta carboxyl of Asp at the N-terminal end of the masking peptide Asp-γ-Glu-γ-Glu-γ-GluGlu to produce the prodrug (12ADT)-Asp-γ-Glu-γ-Glu-γ-GluGluOH (G-202).
The chemical name for G-202 is (8-O-(12-aminododecanoyl)-8-O-debutanoyl-thapsigargin) aspartate-γ-glutamate-γ-glutamate-γ-glutamate-glutamate OH. It is sometimes referred to in an abbreviated fashion: (12ADT)Asp-γ-Glu-γ-Glu-γ-Glu-GluOH, where 12ADT represents the thapsigargin derivative and Asp-γ-Glu-γ-Glu-γ-Glu-GluOH represents the PSMA-cleavable masking peptide. G-202 is a tan to white solid with a molecular weight of 1409.52.
G-202 consists of a PSMA-selective 5 amino acid peptide substrate coupled to a highly cytotoxic analog of the natural product thapsigargin. See, e.g., Denmeade, S. R., et al., J. Natl. Cancer Inst. 2003; 9: 990-1000; and U.S. Pat. Nos. 7,767,648 and 7,468,354. Thapsigargin is isolated from the seeds of the plant Thapsia garganica , which grows as a weed throughout the Mediterranean basin. See, e.g., Rasmussen, U., et al., Acta Pharm. Suec. 1978; 15:133-140. Thapsigargin functions by potently inhibiting a critical intracellular protein, the sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA) pump whose normal function is to maintain intracellular calcium homeostasis in all cell types. Proper function of the SERCA pump is required for the viability of all cell types. Thus, thapsigargin inhibition of the SERCA pump results in the death of all cell types tested, both normal and malignant. See, e.g., Thastrup, O., et al., Proc. Natl. Acad. Sci. USA 1990; 87:2466-2470; Denmeade, S. R., Cancer Biol. Ther. 2005; 4:14-22.
On this basis, G-202 was designed to target this potent cytotoxin with a unique mechanism of action for selective activation by PSMA produced by prostate cancer epithelial cells within sites of prostate cancer and by tumor endothelial cells in other cancer cell types, for example, hepatocellular carcinoma. Without being bound by any particular theory, it is believed that PSMA is an extracellular carboxypeptidase that sequentially cleaves off acidic amino acids from the G-202 prodrug to eventually liberate a cytotoxic analog of thapsigargin. See, e.g., Pinto, J. T., et al., Clin. Cancer Res. 1996; 2:1445-1451; Carter, R. F., et al., Proc. Natl. Acad. Sci., USA 1996; 93:749-753; Mhaka, A., et al., Cancer Biol Ther. 2004; 3:551-558. This highly lipophilic analog, termed 12ADT-Asp, upon release from its water soluble peptide carrier, rapidly partitions into the surrounding cell membranes. See, e.g., Jakobsen, C. M., et al., J. Med. Chem. 2001; 44:4696-4703. The analog then binds to the SERCA pump producing a sustained elevation in intracellular calcium which results in activation of apoptosis (see, e.g., FIG. 1 ; Denmeade, S. R., et al. J. Natl. Cancer Inst. 2003; 9: 990-1000; Singh, P., et al., J. Med. Chem. 48, 3005-3014 (2005)). Because the 12ADT-Asp analog is released extracellularly into the tumor microenvironment, every cell does not need to produce PSMA to be killed by the prodrug activation. A substantial bystander effect is achieved by the release of the active drug into the tumor microenvironment.
Preclinical studies with G-202 have demonstrated that the prodrug is selectively activated by PSMA in vitro and is ˜60-fold more toxic to PSMA expressing vs. PSMA non-expressing tumor cells. PSMA shows significant growth inhibition against a panel of prostate, breast, renal, liver, and bladder cancers in vivo at doses that are minimally toxic to the host animal. See, e.g., Denmeade, S., et al., www.ScienceTranslationalMedicine.org, Vol. 4, Issue 140: 1-12 (2012).
In one embodiment, the present invention provides methods for the production of G-202 (Formula 1), crude G-202 (Formula 9), and certain intermediates. The overall reaction scheme for crude G-202 is summarized and set forth as shown in FIG. 1 .
Thus, in one embodiment, the compound (Formula 2)
is utilized as a starting material. This compound is reacted with sodium ethoxide in ethanol at a temperature of −15±5° C. to produce
(Formula 3). Next, this compound (8-O-debutanoylthapsigargin (DBTg)) is reacted with 4-dimethylaminopyridine (4-DMAP), 12-(tert-butoxycarbonylamino)dodecanoic acid (12-Boc-AD or Boc-12-AD) and dichloromethane until a homogeneous solution is obtained. Diisopropylcarbodiimide (DIC) is added to this solution to obtain:
(Formula 5) (Boc-12ADT or 12-Boc-ADT). Boc-12ADT is dissolved in dichloromethane (CH 2 Cl 2 ) and mixed with trifluoroacetic acid (TFA) to yield:
(Formula 6) (12-ADT). Thereafter, this compound, 12-ADT, is then reacted with the purified peptide:
(Formula 7) in a mixture of dimethylformamide (DMF) and hydroxybenzotriazole hydrate (HOBt). Diisopropylethylamine (DIPEA) is added to the mixture, followed by (3-Dimethylaminopropyl)ethylcarbodiimide hydrochloride (EDC-HCl) to produce:
(Formula 8) (PG-202). Next, this compound is reacted with dichloromethane, triethylsilane (Et 3 SiH) and trifluoroacetic acid to produce the compound:
(Formula 9) (crude G-202). Crude G-202 is then purified to produce the compound of Formula 1.
The present invention also provides methods for the production of the reactant Boc-12-AD (Formula 4), which is used in the production of crude G-202 (Formula 9), as shown in the reaction scheme above. The overall reaction scheme for Boc-12-AD may be summarized and set forth as follows:
Previously, Boc-12-AD was constructed in one step from 12-aminododecanoic acid by treatment with excess di-tert-butyldicarbonate in the presence of sodium hydroxide (Scheme 1). After recrystallization from heptane, the desired product was reported to be obtained in excellent yield and purity. However, due to very little UV absorption upon HPLC analysis, the Boc-12-AD purity was determined by NMR.
When 12-aminododecanoic acid is treated in t-butanol with 1.9 equivalents Boc 2 O and 0.98 equivalents of NaOH (5 M) at 40° C., followed by a workup and recrystallization from heptane, it is expected to produce pure Boc-12-AD. However, while the material produced by this method is snow-white and crystalline, analysis by lc/ms indicated that it contained significant amounts of three compounds as shown below (Scheme 2). Due to significant signal overlap, it is likely these impurities are not identifiable by NMR.
Thus, one of the components produced by Scheme 1 is the required Boc-12-AD, but the two others are dimers of the starting material. From structural assignments based solely on lc/ms, impurity 1 is believed to be the free acid and impurity 2 is believed to be the t-butyl anhydride. Analysis of the material before and after the first recrystallization from heptane indicated that it was not effective at removing these impurities. A second crystallization from heptane was found to reduce the amount of impurity 2, but did not reduce impurity 1. The material can also be recrystallized from ethyl acetate or a mixture of methyl t-butyl ether (MTBE) and heptane with good recovery. However, both systems reduce impurity 2 but have little effect on the amount of impurity 1. If left in the reactant, impurity 1 will react with DBTg and create impurities throughout the rest of the synthesis which are very difficult to remove.
Thus, provided herein is a novel method that essentially eliminates the impurities generated in the existing synthesis. The method includes the generation of Boc-12-AD via the three-step route shown in Scheme 3 below.
Acid-catalyzed esterification of 12-aminododecanoic acid generates the methyl ester hydrochloride. This reaction was followed by protection of nitrogen as the t-butyl carbamate and finally hydrolysis to give the desired product.
While this route is longer (3 steps versus 1), it is very high-yielding (96%, 97% and 98% for each step respectively) and it essentially eliminates the formation of the dimer impurities. Additionally, for the reaction to convert DBTg to Boc-12-ADT, the byproduct diisopropylurea (DIU) is removed by precipitation from MTBE/heptane; unreacted DIC is removed by a novel ACN/heptane partitioning, and a silica gel purification of 12-ADT-TFA was developed.
Scheme 3 may also be used to generate variations of Boc-12-AD, for example, compounds having the formula Boc-(CH 2 ) n —NH 2 , wherein n is an integer greater than 2. For such compounds, the starting material will have the formula (CH 2 ) n —NH 2 , wherein n is an integer greater than 2 (Formula 13).
In another embodiment, the present invention provides the compounds of Formula 1 through Formula 12, including variations and derivatives thereof, and methods of using the same. In another embodiment, the present invention provides the compounds of Formula 1 through Formula 12, including variations and derivatives thereof, made by the methods disclosed herein.
EXAMPLES
The invention will now be described in greater detail by reference to the following non-limiting examples.
Example 1
Preparation of 8-O-Debutanoylthapsigargin (DBTg)
A 22-L round bottom flask (RBF) was charged with 709 g of thapsigargin (weight corrected for water and solvents was 693 g) followed by 4.6 L of ethanol. The mechanical stirrer was started; the material stirred until homogeneous, and then cooled to −15±5° C. with a 75/25 methanol/water/dry ice bath. A 20% solution of sodium ethoxide in ethanol (445 ml) was added slowly while keeping the temperature −15±5° C. An in-process reaction check at 20 minutes indicated complete reaction (1% Tg) and glacial acetic acid (85 ml) was added quickly to quench the reaction. After the quench, the reaction was allowed to warm and concentrated on a rotovap to remove the bulk of the ethanol. The resultant thick oil was dissolved in methyl t-butyl ether (MTBE) and washed with deionized water, saturated sodium bicarbonate, deionized water, and saturated sodium chloride. The organic layer was dried over sodium sulfate, filtered and concentrated on a rotovap. After co-distilling with MTBE (2×) the resultant amorphous dry foam/solid was placed in a vacuum oven and dried without heat for 15 hours and 56 minutes. The weight of DBTg was 613 grams (95% recovery) with 97% purity by HPLC area and no ethanol detected. The material passed all specifications and was released.
Example 2
Preparation of 12-ADT-TFA
A 12-liter round bottom flask was charged with 607 grams of 8-O-debutanoylthapsigargin (DBTg), 139 grams of 4-dimethylaminopyridine (4-DMAP), 342 grams of 12-(tert-butoxycarbonylamino)dodecanoic acid (12-Boc-AD) and 2050 ml of dichloromethane. The contents of the flask were stirred until a homogeneous solution was obtained followed by addition of the diisopropylcarbodiimide (DIC, 192 ml). After passing a reaction check at 3 hours, the dichloromethane was removed by concentration on a rotovap followed by chasing with MTBE. The reagent byproduct diisopropylurea (DIU) was removed by precipitation from MTBE and heptane followed by filtration. The organic mother liquor was transferred to a separatory funnel and the material washed with 0.5 M HCl (2×), 0.6 M sodium bicarbonate (2×), and saturated sodium chloride. The organic layer was dried over sodium sulfate, filtered and concentrated. In order to remove residual reagent DIC, the material was dissolved in acetonitrile (ACN) and washed with n-heptane. The ACN layer was transferred to the rotovap, concentrated, and then co-distilled with MTBE to remove ACN. The resultant 12-Boc-ADT was dissolved in dichloromethane, transferred to a 22-L round bottom flask and cooled to <10° C. Trifluoroacetic acid was added via addition funnel while maintaining a temperature <15° C. An in-process reaction check at 30 minutes indicated no starting material remained. The reaction solution was transferred to a rotovap, concentrated and co-distilled with dichloromethane (2×). The material was further purified by plug filtration through silica gel. The material was loaded onto the silica bed with dichloromethane and eluted with dichloromethane (4 column volumes CVs), 10% acetone/90% dichloromethane (8 CVs) and then acetone (20 CVs) to give 658 grams of 12-ADT-TFA (71% yield for two steps) with a purity of 98% by area, 0.12% dichloromethane and 1.6% acetone.
Example 3
Preparation of PG-202
Residual ammonium acetate was removed from the peptide (774 g) by dissolving the peptide in MTBE and washing with 0.5 M HCl, deionized water, and saturated sodium chloride. The resultant organic solution was dried over sodium sulfate, filtered and concentrated. This was followed by dissolving in MTBE and azeotropic distillation with heptane. The purified peptide was charged to a 12-L RBF followed by DMF (1.3 L), hydroxybenzotriazole hydrate (242 g), 12-ADT-TFA (644 g), and an additional 1.8 L of DMF. Next, DIPEA (153 ml) was added followed by EDC-HCl. The first reaction check at 6 hours and 5 minutes indicated significant starting material remained (22.6% 12-ADT-TFA). The second reaction check at 12 hours and 24 minutes indicated the reaction had stalled (22% 12-ADT-TFA). Therefore, after 13 hours and 6 minutes additional EDC-HCl was added (48 g, 0.35 equiv). The reaction was allowed to stir overnight and an in-process check at 24 hours 40 minutes indicated the reaction had progressed but 18% 12-ADT-TFA still remained. At 25 hours and 16 minutes, additional DIPEA was added (153 ml, 1.22 equiv). The next reaction check (26 hrs 17 minutes) showed 10% remaining 12-ADT-TFA. This indicated that additional base was driving the reaction forward. Another DIPEA charge (158 ml, 1.26 equiv) at 28 hrs 15 minutes pushed the reaction to 95% completion (30 hours 20 minutes). The reaction mixture was diluted into MTBE, washed with 0.5 M HCl (2×), deionized water (2×), saturated sodium bicarbonate, and saturated sodium chloride. The organic layer was dried over sodium sulfate, filtered and concentrated. The PG-202 was dissolved in dichloromethane, placed on 10 kg of silica, and eluted with six column volumes of 55% n-heptane:45% acetone. The eluent was concentrated on a rotovap, and azeotroped with MTBE to give 1048.7 grams of PG-202 (72% yield) as an off-white powder that passed all specifications. The purity was 89% and the material contained 2.9% MTBE, 0.76% n-heptane, and 0.049% DMF.
Example 4
Preparation of Crude G-202
A 22-L round bottom flask was charged with PG-202 (500 grams), 2.8 liters of dichloromethane and 360 ml of triethylsilane. The material was stirred until homogeneous and then cooled to ≦10° C. Trifluoroacetic acid (2.8 L) was added while maintaining temperature ≦10° C. (31 minutes). The reaction was stirred at ≦10° C. for 34 minutes and then the cooling bath was removed and the reaction allowed to warm to room temperature. A reaction check after 16 hours and 52 minutes indicated the reaction was complete. The reaction mixture was transferred to a rotary evaporator and concentrated to an oil. This was followed by co-distillation with DCM (4×5.5 L) to obtain a solid that was dried in a vacuum oven at ≦40° C. for 12 hours and 6 minutes to give 513 grams of crude G-202 (68.5% yield) as an off-white powder. The purity was 79% by HPLC area % and 50.5 weight %. The material passed all specifications and was released.
The crude G-202 was purified by C18 reverse-phase chromatography followed by a concentration column which reduced the volume of water before lyophilization and converted the TFA salt into the free base. The G-202 was purified in several runs, one example of which is described below.
Example 5
Reverse-Phase Chromatographic Purification Biotage 150 L KP-C18-HS Column-Run 1
The load for the first run was the crude G-202 (HCN 5541-08411-A) which was dissolved in 2.64 L of 50% ACN/WFI with 0.1% TFA, diluted with WFI to 35%, and stored at ambient temperature overnight. The load solution was filtered through a sintered glass filter (4-5.5 μm) and loaded onto the column. The column was eluted with 35%, then 40%, followed by 45% acetonitrile/WFI with 0.1% TFA. The elution was monitored by UV at 235 nm. As expected, G-202 eluted off in 45% acetonitrile/WFI with 0.1% TFA. When G-202 came off the column, one gallon fractions were collected and assayed by the short HPLC method (P/N 5300.000). Based on HPLC chromatographic purity, the fractions with area % >95% were combined to make two mini-pools (45% F3-F18 and 45% F4-F17) which were analyzed by HPLC (P/N 5289). Both mini-pools showed >98% chromatographic purity. Therefore, 45% F3-F18 were combined to give a G-202 product pool (54 L) containing 95.7 g G-202 as determined by HPLC using the G-202 TFA salt (2695-64-15) as standard.
Example 6
Concentration-Purification Column Run 1
The G-202 product pool (54 L) from run 1 was diluted with the given volume of water to make a 25% can/WFI solution, and reloaded on the Biotage 150M KP-C4-WP column which had been equilibrated with 25% ACN/WFI (20 L). The column was rinsed with 25% ACN/WFI to remove TFA, and 40% ACN/WFI to remove the impurity with RRT 0.65. At the end of 40% ACN/WFI elution, G-202 started to come off. The C4-WP column was continued eluting with 90% ACN/WFI. G-202 was concentrated in about 4 L of 40% ACN/WFI and 15 L of 90% ACN/WFI.
Example 7
Synthesis of the t-Butylcarmate Protected Linker (BOC-12-AD) (Formula 4)
BOC-12-AD was synthesized according to the scheme below:
A 22 L 3N RBF was flushed with N 2 and placed under a N 2 bleed. The flask was charged with 14 L of MeOH followed by 825 mL (2.5 eq.) of acetyl chloride which was added via addition funnel over ca. 45 minutes. There is an exotherm of ca. 10° C. during the addition. The resulting solution was cooled to <25° C. and 1.0 Kg (1.0 eq.) of (1, as shown in the scheme above) is added all at once at room temperature. The reaction mixture was stirred for ca. 1.5 hr. at room temperature and considered complete based on LC/MS. The reaction mixture was concentrated to a total volume of ca. 4.5 L removing the majority of the MeOH to form a thick white slurry. To the slurry at room temperature 5.5 L of MTBE was added and the resulting suspension cooled to <10° C. for ca. 1 hr. The product was isolated via filtration and washed 3 times with ca. 3 L of cold MTBE. The product (2, as shown in the scheme above) was dried a short time on the filter transferred to a drying tray and further dried overnight in the vacuum oven at ca. 45° C. to give 1197 g of (2) as a white crystalline solid (97%) recovery.
A 22 L 3N RBF was flushed with N 2 and placed under a N 2 bleed. The flask was charged with 525 g (1.0 eq.) of (2), 6.0 L of CH 2 Cl 2 , 24.1 g (0.1 eq.) of DMAP and 451 g (1.05 eq.) of Boc 2 O. The above materials were rinsed forward with 2.0 L of additional CH 2 Cl 2 . Next, 577 mL (2.1 eq.) of triethylamine was added drop wise over 20-25 min. via addition funnel. There was a slight exotherm and moderate gas evolution during the addition. A light amber solution forms during the addition. The reaction mixture was stirred for ca. 1 hr. at room temperature and determined complete TLC. The reaction mixture was diluted with 3.0 L of CH 2 Cl 2 and 3.0 L of 1M HCl added before stirring for ca. 10 minutes. Layers were separated and the organics washed 1×3.0 L of sat. NaHCO 3 . The organics were dried over Na 2 SO 4 , filtered and concentrated to ca. 1.0 to 1.4 L total volume a very light suspension formed. The drying salts were washed 3 times with a total of 1.0 L of MTBE. The MTBE was removed via concentration on the roto-vap back down to a total volume of ca. 1.0 L to remove residual CH 2 Cl 2 . The light suspension that formed was diluted with 1.5 L of additional MTBE and stirred overnight. The insoluble urea impurity was removed via filtration and the solids washed three times with a small amount of MTBE. The filtrate containing the product was combined with the filtrate from a second run (same scale) and the combined filtrates were concentrated to a volume of ca. 1-1.4 L resulting in a thick light green clear oil. The oil was cooled to room temperature with stirring. During the cooling process the product began to crystallize. To the stirring suspension 3.0 L of heptane was added at room temperature and the suspension further cooled to <10° C. The suspension was held for ca. 1.5 hr. at <10° C. before isolation via filtration. The product (3) was washed 3× with a total of 2.0 L cold heptane dried a short time on the funnel and transferred to drying trays. The product was dried under full vacuum at room temperature over night to give 1247 g of (3) as a white crystalline solid (96%) recovery.
A 22 L 3N RBF was flushed with N 2 and placed under a N 2 bleed. The flask was charged with 5.3 L of MeOH and the stirrer started. Next, 550 g (1.0 eq.) of (3) was added and rinsed with an additional 2.0 L of MeOH. To the stirring solution 4.17 L of 1M NaOH (2.5 eq.) via addition funnel over ca. 30-40 minutes. The resulting slurry was heated to ca. 50° C. and complete by TLC after 30 minutes. During the heating a solution is formed. The solution was cooled to <30° C. and quenched with 1.0 L of 6 M HCl over 30 minutes (pH˜3) a white slurry develops. The slurry was stirred at room temperature for ca. 1 hr and the product (4) isolated via filtration. The product was rinsed out of the flask with ca 1.0 to 1.5 L of DI water, the product was washed with 1.0 L of water in two portions dried a short time on the filter and transferred to a tared drying trays. The product was further dried over weekend ca. 40° C. under full vacuum to give 508.5 g of (4) as a white solid (97%) recovery. The second batch (same scale) was done the same as batch 1 and produced 513.7 g of (4) a yield of 98%.
The contents of the articles, patents, and patent applications, and all other documents and electronically available information mentioned or cited herein, are hereby incorporated by reference in their entirety to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference. Applicants reserve the right to physically incorporate into this application any and all materials and information from any such articles, patents, patent applications, or other documents.
The inventions illustratively described herein may suitably be practiced in the absence of any element or elements, limitation or limitations, not specifically disclosed herein. Thus, for example, the terms “comprising”, “including,” containing”, etc. shall be read expansively and without limitation. Additionally, the terms and expressions employed herein have been used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed. Thus, it should be understood that although the present invention has been specifically disclosed by preferred embodiments and optional features, modification and variation of the inventions embodied therein herein disclosed may be resorted to by those skilled in the art, and that such modifications and variations are considered to be within the scope of this invention as defined by the appended claims.
The invention has been described broadly and generically herein. Each of the narrower species and subgeneric groupings falling within the generic disclosure also form part of the invention. This includes the generic description of the invention with a proviso or negative limitation removing any subject matter from the genus, regardless of whether or not the excised material is specifically recited herein.
All of the compositions and methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the compositions and methods of this invention have been described in terms of preferred embodiments, it will be apparent to those of skill in the art that variations may be applied to the compositions and methods and in the steps of the sequence of steps of the method described herein without departing from the concept, spirit and scope of the invention. More specifically, it will be apparent that certain agents which are both chemically and physiologically related may be substituted for the agents described herein while the same or similar results would be achieved. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the invention as defined by the appended claims.
Other embodiments are set forth within the following claims. | Provided herein are methods of making the compound of Formula I:
and certain intermediates involved in such process. | 0 |
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates, in general, to a method and system, to be utilized with wireless communications systems, having cellular architectures which utilize digital clocked systems (such as Time Division Multiple Access (TDMA), Code Division Multiple Access (CDMA), or similar technologies), and which interface with public switched telephone networks (PSTNs). In particular, the present invention relates to a method and system, to be utilized with wireless communications systems, having cellular architectures which utilize digital clocked systems (such as TDMA, CDMA, or similar technologies), and which interface with PSTNs, wherein the method and system increase the reliability of such wireless communications systems by avoiding communication failures at the wireless communication system-PSTN system interfaces.
2. Description of the Related Art
The present invention is related to wireless communication systems, and, in particular, to wireless communications systems which have both a cellular architecture (e.g., cellular telephony, personal communications systems) and which utilize CDMA (or similar technologies) and which interface with public switched telephone networks (PSTNs). Wireless communication refers to the fact that transmission between sending and receiving stations occurs via electromagnetic radiation (e.g., microwave) not guided by any hard physical path. Cellular architecture refers to the fact that the wireless system effects service over an area by utilizing a system that can (ideally) be pictographically represented as a cellular grid. CDMA stands for Code Division Multiple Access, which is a type of spread spectrum technology, originally developed for military application and thereafter adapted for civilian use.
Wireless cellular communication utilizing CDMA is the latest incarnation of a technology that was originally known as mobile telephone systems. Early mobile telephone system architecture was structured similar to television broadcasting. That is, one very powerful transmitter located at the highest spot in an area would broadcast in a very large radius. If a user were in the usable radius, then that user could broadcast to the base station and communicate by radio telephone to the base station. However, such systems proved to be very expensive for the users and not very profitable to the communication companies supplying such services. The primary limiting factor, or problem, of the original mobile telephone systems was that the number of channels available for use was limited due to severe channel-to-channel interference within the area served by the powerful transmitter.
This problem was solved by the invention of the wireless cellular architecture concept. The wireless cellular architecture concept utilizes geographical subunits called “cells” and encompasses what are known as the “frequency reuse” and “handoff” concepts. A cell is the basic geographic unit of a cellular system. Cells are defined by base stations (a base station consists of hardware located at the defining location of a cell and includes power sources, interface equipment, radio frequency transmitters and receivers, and antenna systems) transmitting over small geographic areas that are represented (ideally) as hexagons. The term “cellular” comes from the honeycomb shape of the areas into which a coverage region, served via two or more base stations, is divided when the mathematically ideal hexagonal shape is used to represent the usable geographic area of each of the two or more base stations. It is to be understood that, although the mathematically ideal shape of the cell is a hexagon, in practicality each cell size varies dependent upon the landscape (e.g., a base station transmitting on a flat plane will closely approximate the ideal hexagon, whereas a base station transmitting in a valley surrounded by hills will not closely approximate a hexagon due to the interference from the surrounding hills).
The first large-scale wireless communications system utilizing cellular architecture in North America was the Advanced Mobile Phone Service (AMPS) which was released in 1983. With the introduction of AMPS, user demand for bandwidth was initially low until users became acquainted with the power of the system. However, once users became acquainted with the power of cellular, the demand for the service increased. Very quickly, even the extended number of channels available utilizing the cellular concepts of reduced power output and frequency reuse were quickly consumed by user demand in certain geographic areas, and a problem arose with respect to capacity.
Engineers responded to the problem by devising the Narrowband Analog Mobile Phone Service (NAMPS). NAMPS utilizes frequency division multiplexing to transmit three transmit/receive channels in the same bandwidth wherein AMPS had previously only transmitted one transmit/receive channel. Thus, NAMPS essentially tripled the capacity of AMPS. However, even though NAMPS essentially tripled the capacity of AMPS, the extended number of channels available with NAMPS were quickly consumed by user demand in certain geographic areas, and a problem again arose with respect to capacity.
Engineers responded to this new problem by devising Digital AMPS (or DAMPS, also known as TDMA). In DAMPS/TDMA time division multiple access techniques are utilized to multiplex user data together. Furthermore, digital data compression techniques are utilized at both the transmission and reception ends. These techniques give rise to increased capacity, and clarity, even exceeding that of NAMPS. However, as was the case with both AMPS and NAMPS, the increased bandwidth capacity of DAMPS/TDMA has been quickly consumed by user demand in certain geographic areas.
Subsequent attempts to increase cellular telephony bandwidth capacity tended to be variations on the foregoing described themes. However, it became apparent that some new communications technology would be necessary to give rise to any significant increase in bandwidth beyond that available with the foregoing described technologies. It was decided within the industry that such new technology would be standard CDMA, which stands for Code Division Multiple Access.
Notice that in all the foregoing described technologies, the method of using multiple transmit/receive channels with each such transmit/receive channel utilizing a different pair of frequencies was maintained throughout. Standard CDMA breaks completely with this method of communication.
Standard CDMA utilizes cellular architecture and a type of hand-off. However, in standard CDMA, transmission and reception is done by all users on the same frequency. Standard CDMA is able to achieve this feat by insuring that the signals from different users are adjusted such that the signals do not interfere with each other to the point of being unable to understand the messages from the different users.
The way in which standard CDMA works is somewhat analogous to a situation in which two English speaking persons are communicating in a room wherein many other non-English speakers are also communicating in a language which the two English speakers do not understand. Since the two English speakers do not understand the language spoken by the non-English speakers in the room, the conversations of their non-English-speaking counterparts will be interpreted by the two English speakers as meaningless “noise.” Consequently, since the English speakers will attach no meaning to the “noise,” the English speakers will be able to disregard the “noise” and continue to engage in their conversation provided that they both speak loudly enough so that each can be understood by the other despite the “noise” generated by their non-English-speaking counterparts. This is true even though all persons in the room are talking, or communicating, in the same band of sound frequencies which the human ear can hear.
Standard CDMA is able to achieve the same affect by modulating the signal of each user within a particular cell with a “pseudo-noise” code which, in effect, will make each user in the cell appear as if each user were, in effect, “speaking a different language,” thereby insuring that the meaning of a signal generated by one user within the cell will not be drowned out by the meaning contained within the signal generated by one or more other users in the cell. Provided, of course, that each user speaks “loudly” enough (or transmits enough power) to be understood over the “noise” generated by the other users in the CDMA cell.
Standard CDMA utilizes digital data technology to achieve the foregoing. Standard CDMA utilizes complex digital codes to modulate user data prior to transmission within a cell. The standard CDMA pseudo-noise codes are chosen such that a modulated signal, when transmitted upon a carrier frequency within the cell, approximates white (or Gaussian) noise, and does not greatly interfere with any other signal transmitted upon the same carrier frequency within the cell. Upon reception, a similar pseudo-noise code is used to demodulate the signal and recover the data that was transmitted.
When digital data technology is utilized with the standard CDMA pseudo-noise codes, it is necessary for all transmitters and receivers within a cell to be synchronized to the same digital clock. This synchronization is provided by use of a “pilot” signal which is transmitted by the base station. Each mobile subscriber unit within a cell “locks” to this pilot signal and thereafter utilizes it as the clock signal for digital data-processing.
In standard CDMA, each base station transmits and receives on the same carrier frequency. Furthermore, in standard CDMA, each base station transmits the same period digital code which is utilized as the pilot signal within each cell. Ordinarily, such a situation would give rise to severe interference between cells. Standard CDMA avoids this problem by phase-shifting (or time-staggering) the pilot signal, or digital code, transmitted within adjacent cells. Within standard CDMA, the carrier signal, pilot code, pseudo-noise codes, and phase-shifting (or time-staggering) of the pilot codes utilized in adjacent cells have all been chosen to work together such that inter-cell interference is minimized. Thus, not only does standard CDMA ensure that users in each cell appear to each other as if they are “speaking different languages,” but standard CDMA ensures that adjacent cells appear to each other “as if” each cell was in fact “speaking a different language.”
It has been stated that when digital data technology is utilized with the standard CDMA pseudo-noise codes, it is necessary for all transmitters and receivers within a cell to be synchronized to the same digital clock. This synchronization is provided by use of a “pilot” signal which is transmitted by the base station. Each mobile subscriber unit within a cell “locks” to this pilot signal and thereafter utilizes it as the clock signal for digital data-processing. The question naturally arises as to the origin of the clock signal used by the CDMA system.
The answer is that the clock signal originates with the Global Positioning System (GPS). The GPS is a network of geostationary satellites which is utilized to provide precise global positioning. Each GPS satellite contains a clock synchronized to the clocks on the other GPS satellites. One of the features of the GPS is that it emits a “ping,” or clock signal, every 20 msec. Because each GPS satellite is geostationary, each GPS satellite is at roughly the same distance from the earth's surface (i.e. Geostationary Height). Consequently, each “ping” from a GPS satellite reaches the earth's surface essentially simultaneously.
Because each “ping” reaches the earth's surface essentially simultaneously, CDMA utilizes such pings as its system clock. Thus, the GPS 20 msec ping provides an effective “clock” to synchronize the CDMA transmitters and receivers, and is consequently utilized for that purpose. Thus, the GPS provides an effective way to synchronize a CDMA network which may be spread over a large geographic area.
In many rapidly developing, but previously undeveloped, areas of the world, such as the former Soviet Union, and the Central and South American republics, only CDMA systems are in place. That is, no substantial pre-existing PSTNs are in place. However, in long-developed areas of the world, such as the United States of America, Canada, and the European Union, there are extensive infrastructures of PSTNs present. In such areas, it is necessary for CDMA systems to interface with the PSTN systems in order for CDMA to be commercially viable and to provide seamless communications services to the residents of such areas. Such interfacing poses multiple problems, but one of the most significant arises from the fact that the timing signals utilized by the CDMA systems and the PSTN systems are not synchronized.
A PSTN is a common carrier network that provides circuit switching for the general public. It is usually a domestic communications network that is accessed by telephones, private branch exchange trunks, and data equipment such as modems. One common type of data carried by PSTNs is digitized voice data.
The human voice amounts to an analog (continuous time) signal. However, from a data communications standpoint, it has been found that transmission of the human voice in digital (discrete time) format produces more acceptable results. Consequently, it is necessary to convert the human voice, which is an analog signal, to a digital signal. After transmission, the digital signal is a re-converted to an analog signal which the human ear can hear.
It has been found empirically, that a human voice signal containing at least frequencies up to the 4000 hertz range is acceptable to most listeners. Consequently, it is necessary to sample the voice signal at two times that frequency such that frequencies up to the 4000 hertz range can be adequately captured. That is, it has been found that sampling a voice signal 8,000 times a second will result in acceptable performance.
One way in which the analog to digital conversion is done is known as Pulse Code Modulation (PCM). In PCM systems the analog signal is sampled once every 8000 seconds, which equates to 1 PCM sample every 125 micro-seconds. When a sample occurs, the magnitude of the analog voice signal is noted. Thereafter, some relative scale is utilized to denote that magnitude. Normally, three bits (binary information units, typically denoted by the symbols “0” and “1”) are utilized to quantize the analog signal digitally.
Since a PCM system samples data at specific time intervals, a clock signal is needed to synchronize the system. In a PSTN, such a clock signal is derived from what is known as the “PSTN Clock.” The PSTN Clock is derived from a centrally located atomic clock located at some central geographic location. There are various of these PSTN Clocks scattered throughout the world. However, for the purposes of this discussion, the central fact to be gleaned is that such PSTN Clocks are not synchronized with the GPS clocks utilized to synchronize the CDMA systems. This lack of synchronization can give rise to several problems, one of which is illustrated in FIG. 1 .
Refer now to FIG. 1 . FIG. 1 is a partially schematic diagram which will be used to illustrate problems that arise due to the fact that the clocks used to control CDMA systems and PSTN systems are not synchronized. Shown in FIG. 1 is CDMA voice coding subsystem 100 . On the right-hand side of FIG. 1 appears PSTN system 102 . PSTN system 102 is utilizing PCM and is delivering a PCM input stream 104 to CDMA voice coding subsystem 100 . Further shown is that PSTN system 102 utilizes PSTN clock 106 , which as has been discussed, is some type of atomic clock at some defined ground-based location.
Shown is that within CDMA voice coding system 100 resides a digital signal processor (DSP) 110 . Contained within DSP 110 is PCM-CDMA encoder 112 which accepts PCM sample blocks, signal processes (or encodes) them, and delivers such encoded blocks to CDMA system 108 which appears on the left-hand side of FIG. 1 .
Upon receipt of each PCM sample, PCM sample detection circuitry (not shown) interrupts DSP 100 in order to inform DSP 100 that a PCM sample has been received on the PSTN input stream 104 . In response to this interrupt, DSP 100 keeps a count of the number of PCM samples received during a particular time interval; furthermore, DSP 100 loads the received PCM sample into a PCM sample input buffer (not shown).
Shown is that CDMA system 108 is controlled, or synchronized by, GPS clock 114 . Consequently, when the 20 msec GPS “ping” occurs, CDMA system 108 alerts DSP 110 to the fact that the 20 msec ping has occurred. In response, PCM-CDMA encoder 112 retrieves the stored PCM samples from the PCM sample input buffer (not shown), effectively emptying the PCM sample input buffer (not shown) wherein the previously received PCM samples had been stored. After retrieval, PCM-CDMA encoder 112 processes the retrieved PCM sample block and creates a CDMA packet and places the created CDMA packet into a CDMA packet output buffer (not shown). Thereafter, the created CDMA packet is transmitted from CDMA voice coding subsystem 100 under the dictates of GPS clock 114 . The CDMA packet leaves CDMA voice coding subsystem 100 via CDMA packet output stream 116 .
An essentially reciprocal operation occurs in the reverse direction. That is, CDMA packets enter CDMA voice coding subsystem 100 via CDMA packet input stream 118 . Upon receipt of each CDMA packet, CDMA packet detection circuitry (not shown) interrupts DSP 100 in order to inform DSP 100 that a CDMA packet has been received on the CDMA packet input stream 118 . In response to this interrupt, DSP 100 places the received CDMA packet into a CDMA packet input buffer (not shown) and directs CDMA packet-PCM sample decoder 120 , upon completion of any processing it may be engaged in, to thereafter accept the received CDMA packet, decode it into PCM samples, and place the PCM samples into a PCM sample output buffer (not shown). Thereafter, the PCM samples are read out of the PCM sample output buffer under the dictates of the PSTN clock 106 .
Notice that, irrespective of the direction of flow through CDMA voice coding system 100 , since PSTN clock 106 and GPS clock 114 are not exactly synchronized (because the clocks do not communicate), some potential data loss is likely. It has been noted that GPS clock 114 produces a ping every 20 msec. It is also been noted that the PCM system utilizes PSTN clock 106 pulses to produce a PCM sample every 125 micro-seconds (e.g., 1 sec/8,000 samples). Consequently, if PSTN clock 106 and GPS clock 114 were perfectly synchronized (i.e., 20 msec measured on GPS clock 114 was exactly the same as 20 msec measured on PSTN clock 106 , and the transition edges of the clocks occurred precisely the same instances), there would be 160 PCM samples clocked through CDMA voice coding subsystem 100 , on both PCM input stream 104 and PCM output stream 122 , respectively, every 20 milliseconds.
Unfortunately, for the reasons discussed above, PSTN clock 106 and GPS clock 114 are not synchronized. That is, during the normal course of operation of the systems the transition edges of the clock do not occur at the same time or at the same rate (i.e., 20 msec as measured by GPS clock 114 will tend to be slightly different that 20 msec as measured by PSTN clock 106 ). Furthermore, in the event that the clocks differ by more than 1 PCM sample interval (i.e., by more than 125 micro-seconds) sample transmission will eventually begin to trail behind that necessary and eventually data will be dropped due to the finite size of the buffers. This reality can be made clear by a simple example related to PCM input stream 104 .
Assume that the 20 msec ping of GPS clock 114 is either “lagging” or “leading” PSTN clock 106 by a 250 micro-seconds. That is, for every 20 msec deemed to have elapsed by GPS clock 114 , according to PSTN clock 106 the elapsed time appears to be 20 msec plus/minus 250 micro-seconds. Admittedly, from the standpoint of a 20 msec interval, plus/minus 250 micro-seconds does not seem that significant, since such lagging or leading amounts to only 1.25% of the 20 msec period.
However, when viewed from the standpoint of the buffers (not shown) of CDMA voice coding subsystem 100 , it can be seen that the such leading or lagging can become very significant. If GPS clock 114 is lagging PSTN clock 106 by 250 micro-seconds, then when GPS clock 114 pings, 162 PCM samples will have been collected from PCM input stream 104 , rather than PCM samples. Consequently, when PCM-CDMA packet encoder 112 removes 160 PCM samples from the PCM sample input buffer (not shown), two residual PCM samples will remain in the PCM sample input buffer (not shown).
Assuming that GPS clock 114 and PSTN clock 116 remain unsynchronized it can be seen that the PCM packet input buffer (not shown), which has finite capacity, will eventually become full and consequently data will be lost.
If GPS clock 114 is leading PSTN clock 106 by 250 micro-seconds, then when GPS clock 114 pings, 158 PCM samples will have been collected from PCM input stream 104 , rather than 106 PCM samples. Consequently, when PCM-CDMA packet encoder 112 removes the PCM samples from the PCM sample input buffer (not shown), it will find that only 158 PCM samples are present and consequently will be unable to construct the appropriately sized CDMA packet.
An analogous state of affairs exists with respect to CDMA packet input buffers (not shown) and the PCM output, or transmit, buffers (not shown). That is, if GPS clock 114 is lagging PSTN clock 106 by 250 micro-seconds, then the when the GPS clock 114 pings, two PCM sample intervals will have transpired with no PCM samples being ejected on the PCM output stream 122 . If this state of affairs continues, there will be noticeable “data drop” at relatively periodic intervals, which has been empirically determined to provide unacceptable service to users. That is, a human user can hear and be conscious of such “data drops” and finds such occurrences rankling. Conversely, if GPS clock 114 is leading PSTN clock 106 by 250 micro-seconds, when GPS clock 114 pings, there will still be to PCM samples in the PCM sample output buffer (not shown). Consequently, if this state of affairs continues, the PCM sample output buffer (not shown) will eventually fill and data will be lost.
The foregoing problems associated with the potential CDMA clock and PSTN clock mismatching have been recognized in the prior art. With respect to the PCM sample input buffer problem noted above, the solution that has been effected under the prior art has been to constantly interrupt DSP 110 upon every receipt of a PCM input sample on PCM input stream 104 . These interrupts allow DSP 110 to keep a running count of the number of PCM samples in the PCM sample input buffer. Consequently, when GPS clock 114 pings, DSP 110 can determine if more or less PCM samples are present in the PCM sample input buffer then there should be. In response to such determination, DSP 110 either discards the excessive samples present (e.g., when the samples in the PCM sample input buffer are greater than 160 in number), or duplicates the last PCM sample in the PCM sample input buffer when an inadequate number of PCM samples is present (e.g., when the samples in the PCM sample input buffer are less than 160 in number).
An analogous solution has been applied to the problems associated with the CDMA packet input buffers and PCM sample output buffers discussed above. That is, DSP 110 is interrupted every time a PCM sample is clocked out of the PCM sample output buffer. Consequently, DSP 110 is able to keep count of the number of PCM samples in the PCM sample output buffer and is able to discard PCM samples or add PCM samples to the PCM sample output buffer as appropriate in order to ensure that no CDMA input packets are dropped such that no data outage is experienced by users of PSTN system 102 . That is, DSP 110 , by using a count kept based on the multiple interrupts, is able to control the PCM sample output buffer such that data drop is not detectable by a human user and such that the CDMA packet input buffer does not overflow.
While the foregoing described solutions to the problems associated with lack of synchronization between CDMA system clocks and PSTN system clocks works well, it is also apparent that the system generates a tremendous number of interrupts to DSP 110 in order to effectuate the solution. That is, under the present scheme, DSP 110 is interrupted 160 times in every 20 msec interval (as measured by the PSTN clock) with respect to PCM input stream 104 . In addition, DSP 110 is interrupted approximately 160 times in every 20 msec interval (as measured by the PSTN clock) with respect to PCM samples output on PCM output stream 122 (the interrupts are approximately 160 because, as has been discussed, the number of PCM samples actually placed in PCM sample output buffer depend upon the mismatch between the CDMA and PSTN clocks). Consequently, the present solutions to the foregoing identified problems results in approximately 320 interruptions of DSP 110 every 20 msec or 16,000 interruptions per second. From a computational standpoint, such a high number of interruptions is inefficient. That is, since DSP 110 is responsible for controlling all processing within CDMA voice coding subsystem 100 , it is apparent that it would be advantageous to reduce the number of interrupts of DSP 110 necessary to achieve the solution to the foregoing problems.
In addition to the foregoing noted problems, there were additional motivations for the present invention. One such motivation is that while in traditional methods there is only one call being handled per DSP 110 , there is an impetus in the marketplace to go to multi-call: more than one call being handled per DSP 110 . As can be seen, if an attempt to go to multi-call is made, the foregoing noted problems multiply (e.g., there are now as many interruptions of DSP 110 per call as before, except that these interruptions will be multiplied by the number of calls being handled by DSP 110 ). Thus, marketplace pressure also indicates that it would be advantageous to find a way to maintain the efficacy of the prior art solution, yet do so in a way that reduces the number of interrupts per call.
It is therefore apparent that a need exists for a method and system which will provide a solution to the communication failure problems associated with lack of synchronization between CDMA system clocks and PSTN system clocks, but which will do so in a more computationally efficient way.
SUMMARY OF THE INVENTION
It is therefore one object of the present invention to provide a method and system to be utilized with wireless communications systems having cellular architectures which utilize digital clocked technologies (such as Time Division Multiple Access (TDMA), Code Division Multiple Access (CDMA) or similar spread spectrum technologies), and which interface with public switched telephone networks (PSTNs).
It is yet another object of the present invention to provide a method and system, to be utilized with wireless communications systems having cellular architectures which utilize digital clocked technologies (such as TDMA, CDMA or similar spread spectrum technologies), and which interface with PSTNs, wherein the method and system increase the reliability of such wireless communications systems by avoiding communication failures at the wireless communication system-PSTN system interfaces.
The method and system achieve their objects via communications equipment adapted to do the following: designate a first data-producing system controlled by a first clock; designate a second data-producing system controlled by a second clock; record a timing mismatch between the first clock and the second clock; and dynamically adjusting data flow between the first and the second system in response to the recorded timing mismatch. In one embodiment the first system is a CDMA system controlled by a GPS clock, and the second system is a PSTN system controlled by a PSTN clock.
The above, as well as additional objects, features, and advantages of the present invention will become apparent in the following detailed written description.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objects, and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:
FIG. 1 is a partially schematic diagram which will be used to illustrate problems that arise due to the fact that the clocks used to control CDMA systems and PSTN systems are not synchronized;
FIG. 2 depicts a system wherein one or more embodiments of the present invention may be practiced;
FIG. 3 constitutes a high-level logic flowchart which depicts an embodiment of the present invention;
FIG. 4 depicts a system wherein one or more embodiments of the present invention may be practiced; and
FIG. 5 constitutes a high-level logic flowchart which depicts an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
It was discussed in the background section that the lack of synchronization between CDMA system and PSTN system clocks gives rise to multiple problems. It was also discussed that prior art solutions to the problems result in a relatively large number of interrupts to the primary digital signal processor.
Embodiments of the present invention provide a solution to the foregoing identified problems arising from lack of synchronization between CDMA system clocks and PSTN system clocks, but without generating the relatively large number of interrupts to the primary digital signal processor. At least one of the embodiments of the present invention achieves the foregoing by removing the responsibility for buffer management from a digital signal processor and instead having the buffer management done via the use of a semi-autonomous processor which utilizes a new way of managing buffers and which communicates with the primary digital signal processor.
It should be recognized that the capability of performing the buffer management via the use of a semi-autonomous processor goes against the teaching of the art and initially was met with a great deal of skepticism. That is, since the foregoing described problems arise from a lack of synchronization between CDMA system clocks and PSTN system clocks, it was believed in the prior art that only a method and system tightly time-coupled to the primary digital signal processor would be able to provide the necessary control to solve the problems arising from the lack of synchronization. It was believed that the introduction of a semi-autonomous processor into such environment would create such a timing “wild-card” that the resulting system would prove unworkable given the tight timing constraints imposed by the nature of the problems arising from lack of synchronization between CDMA system clocks and PSTN system clocks. Consequently, the fact that the present invention worked (or solved the problems associated with lack of synchronization between CDMA system clocks and PSTN system clocks), and worked well, came as a complete surprise since the prior art taught away from the method and system of the present invention.
In addition to the foregoing, the prior art also taught away from the present invention in that one embodiment of the present invention modifies the size of the buffers in near real time. The prior art teaching and assumption was that the size of the buffers would always stay constant, and it was felt that real-time manipulation of buffer sizes would prove impractical. Consequently, the fact that the present invention worked (or solved the problems associated with lack of synchronization between CDMA system clocks and PSTN system clocks), and worked well, came as a complete surprise since the prior art taught away from the method and system of the present invention. An embodiment of the present invention will now be discussed.
One embodiment of the present invention is particularly applicable to the situation described in the background section, above. That is, the situation wherein a CDMA clock and a PSTN clock are not synchronized with each other, but in which each individual clock is relatively invariant when viewed in isolation.
Refer now to FIG. 2 . FIG. 2 depicts a system wherein one or more embodiments of the present invention may be practiced. Shown is CDMA voice coding subsystem 200 , which functions, from an overall systems standpoint, essentially in the same way as CDMA voice coding subsystem 100 . However, as can be seen in the figure, CDMA voice coding subsystem 200 has been internally modified such that it now contains semi-autonomous unit 202 . Further shown is that semi-autonomous unit 202 creates, controls, and communicates with two buffers: Buffer A 204 and Buffer B 206 . Semi-autonomous unit 202 communicates with Buffer A 204 and Buffer B 206 via data paths 203 and 205 , respectively. Shown also is that PCM-CDMA packet encoder 212 communicates with semi-autonomous unit 202 via communication link 208 and that PCM-CDMA packet encoder 212 has direct access to Buffer A 204 via data path 205 . Further shown is that semi-autonomous unit 202 receives PCM samples via PCM sample input stream 104 .
In the following discussion, Buffer B 206 will be treated as the working buffer, and as will be shown, the size of Buffer B 206 is dynamically varied in response to system parameters. This fact is illustrated via variable Buffer B boundary 207 .
For the sake of conceptual clarity, the following discussion will treat Buffer A 204 and Buffer B 206 “as if” Buffer A 204 and Buffer B 206 are “stationary” buffers from which the contents of one (Buffer B 206 ) will be transferred into the other (Buffer A 204 ). However, those skilled in the art will recognize that a preferred implementation of the buffers discussed would be to use what are known in the art as “circular buffers.” Consequently, where the following discussion speaks of “transferring,” or “loading,” the contents of Buffer B 206 into Buffer A 204 , it is to be understood that in the preferred embodiment such “transferring” would actually be implemented by communication between semi-autonomous unit 202 and PCM-CDMA packet encoder 212 , wherein ranges of pointers, or register addresses, would be exchanged such that the range of pointers defines Buffer A 204 . Furthermore, it will be understood by those within the art that concomitant changes would also be made internal to semi-autonomous unit 202 to the pointers which define, and delimit, Buffer B 206 such that the range of pointers would properly define Buffer B 206 . Since ranges of contiguous pointers, or register addresses, are utilized and subsequently reutilized to effect Buffer A 204 and Buffer B 206 it can be seen that the register addresses could be represented graphically as a circle; consequently, it is common within the art to refer to such created and managed buffers as “circular buffers.”
Due to the inherent complexity of the “circular buffer” scheme itself, it has been found more clear to discuss embodiments of the present invention as if “stationary” buffers were being utilized which can be read to and written from just “as if” they were fixed computer memory locations. However, it is to be borne in mind that the foregoing discussion, although couched in terms of fixed, or stationary, computer memory buffers, is in a preferred embodiment, implemented via the use of circular buffers by techniques well known to those within the art.
Refer now to FIG. 3 . FIG. 3 will be used in conjunction with FIG. 2 to illustrate an embodiment of the present invention which will alleviate the problems associated with a PCM input buffer, discussed in relation to FIG. 1 above. FIG. 3 constitutes a high-level logic flowchart which depicts an embodiment of the present invention. Method step 300 illustrates the start of the process, which is an entry point where DSP 210 is reset, and which equates to the “powering up” of CDMA voice coding subsystem 200 .
Method step 302 depicts that CDMA voice coding subsystem 200 creates working Buffer A 204 and storage Buffer B 206 , initially of equal size which in one embodiment equates to working Buffer A 204 and storage Buffer B 206 each being of a size capable of holding exactly PCM samples.
Method step 304 illustrates the initialization of an index which points to the start of storage Buffer B 206 . The index points to a register wherein one PCM data sample is stored. Each time PSTN clock 106 pulses, a PCM data sample is stored to a register of storage Buffer B 206 , and the index is incremented; thus, some offset of the index is possible should PSTN clock 106 pulses occur before a first ping of GPS clock 114 is received (that is, the index is being advanced even though PCM samples are not being stored to storage Buffer B 206 ).
Method step 306 shows an inquiry as to whether semi-autonomous unit 202 has received a signal correspondent to a first ping of GPS clock 114 . If no signal correspondent to a first ping of GPS clock 114 has been received, the process returns to method step 306 . However, if a signal correspondent to a first ping of a GPS clock 114 has been received, method step 308 depicts both that each PCM sample received on PCM input stream 204 by semi-autonomous unit 202 is loaded into storage Buffer B 206 and that the index pointing within storage Buffer B 206 is incremented (which will be done in time with the pulses of PSTN clock 106 ).
Method step 310 depicts that subsequent to the loading of a PCM sample into, and incrementing of the index pointing to, storage Buffer B 206 , a determination is made as to (1) whether the index pointing within storage Buffer B 206 indicates that the last register of the currently-set storage area of storage Buffer B 206 has been reached and loaded with data, or (2) whether a signal corresponding to a GPS clock 114 ping has been received. If neither condition is satisfied, the process proceeds to method step 308 and semi-autonomous unit 202 continues loading PCM samples into storage Buffer B 206 . However, in the event that either the last register of the currently-set storage area of storage Buffer B 206 has been reached and loaded with data, or a signal correspondent to a GPS clock 114 ping has been received, the process proceeds to method step 312 .
Method step 312 depicts that an inquiry is made as to whether the last register of the currently-set storage area of storage Buffer B 206 has been reached and loaded with data (i.e., is the index pointing at a register beyond the defined end of specified storage of storage Buffer B 206 ). In the event that the last register of the currently-set storage area of storage Buffer B 206 has been reached and loaded with data, the process proceeds to method step 314 wherein it is depicted that semi-autonomous unit 202 retrieves and augments (by either eliminating a number of the last samples in the data from storage Buffer B 206 if the number of samples is too great, or duplicating the last samples in the data from storage Buffer B 206 if the number of samples is too few) the contents of storage Buffer B 206 such that the total data block size is correct for working Buffer A 204 (it being understood that if the size of storage Buffer B 206 is the same as working Buffer A 204 , then no augmentation is necessary), and thereafter transfers the (possibly augmented) contents of storage Buffer B 206 into working Buffer A 204 .
Data having been transferred from storage Buffer B 206 into working Buffer A 204 , method step 316 illustrates that the index is set to the start of storage buffer B 206 so that it can be refilled. Thereafter, method step 318 indicates that DSP 210 is directed to start processing the working buffer and to utilize PCM-CDMA encoder 212 to encode the PCM data in working Buffer A 204 into a new CDMA packet. Thereafter, the process proceeds to method step 320 .
Returning to the inquiry of method step 312 , in the event that the last register of the currently-set storage area of storage Buffer B 206 has not been reached and loaded with data, the process proceeds to method step 320 which shows the determination as to whether a signal correspondent to a ping of GPS clock 114 has been received subsequent to that discussed in method step 310 . In the event that another signal correspondent to a ping of GPS clock 114 has not been received, the process returns to method step 308 . In the event that another signal correspondent to a ping of GPS clock 114 has been received, the process proceeds to method step 322 .
Method step 322 depicts that the current value of the index pointing within storage Buffer B 206 index is checked to see if the index is equal to the initialized value (recalling that the index is incremented every time a PCM sample is loaded into storage Buffer B, this the value to which it was set in method step 304 , provided that the index is set to “wrap,” or reset to the initial index value once the last buffer storage register of the currently-set storage area of storage Buffer B 206 has been used). If the index is equal to the initialized value, the process proceeds to method step 326 which illustrates that the defined storage area of storage Buffer B 206 is set to its original size.
If the index is not equal to the initialized value, then it is known that a slippage occurred and that the currently-set size of the storage area of storage Buffer B 206 is not correct, so method step 324 shows that the storage area of storage Buffer B 206 is changed so that it equates to the actual number of samples received between the last two signals correspondent to the last two GPS clock 114 pings; that is, the storage buffer is adjusted so that the index will hit its target value (i.e., there will be no slippage) when the next signal correspondent to ping of GPS clock B 114 is received—if the index is behind, the buffer size will be increased, and if the index is ahead, the buffer size will be decreased.
Refer now to FIG. 4 . FIG. 4 depicts a system wherein one or more embodiments of the present invention may be practiced. Shown is CDMA voice coding subsystem 400 , which functions, from an overall systems standpoint, essentially in the same way as CDMA voice coding subsystem 100 . However, as can be seen in the figure, CDMA voice coding subsystem 400 has been internally modified such that it now contains semi-autonomous unit 402 . Further shown is that semi-autonomous unit 402 creates, controls, and communicates with two buffers: Buffer A 404 and Buffer B 406 . Semi-autonomous unit 402 communicates with Buffer A 404 and Buffer B 406 via data paths 403 and 405 , respectively. Shown also is that CDMA packet-PCM sample decoder 420 communicates with semi-autonomous unit 202 via communication link 408 and that CDMA packet-PCM sample decoder 420 loads directly to Buffer A 404 via data path 405 . Further shown is that semi-autonomous unit 402 delivers PCM samples via data stream 409 to Buffer B 406 . Also shown is that Buffer B 406 feeds directly out onto PCM output stream 422 .
In the following discussion, Buffer B 406 will be treated as the working buffer, and as will be shown, the size of Buffer B 406 is dynamically varied in response to system parameters. This fact is illustrated via variable Buffer B 406 boundary 407 .
For the sake of conceptual clarity, the following discussion will treat Buffer A 404 and Buffer B 406 “as if” Buffer A 404 and Buffer B 406 are “stationary” buffers from which the contents of one (Buffer B 406 ) will be transferred into the other (Buffer A 404 ). However, those skilled in the art will recognize that a preferred implementation of the buffers discussed would be to use what are known in the art as “circular buffers.” Consequently, where the following discussion speaks of “transferring,” or “loading,” the contents of Buffer B 406 into Buffer A 404 , it is to be understood that in the preferred embodiment such “transferring” would actually be implemented by communication between semi-autonomous 402 unit and CDMA packet-PCM sample decoder 420 , wherein ranges of pointers, or register addresses, would be exchanged such that the range of pointers defines Buffer A 404 . Furthermore, it will be understood by those within the art that concomitant changes would also be made internal to semi-autonomous unit 402 to the pointers which defined, and the limit, Buffer B 406 such that the range of pointers would properly define Buffer B 406 . Since ranges of contiguous pointers, or register addresses are utilized and subsequently reutilized to effect Buffer A 404 and Buffer B 406 it can be seen that the register addresses could be represented graphically as a circle; consequently, it is common within the art to refer to such created and managed buffers as “circular buffers.”
Due to the complexity of the “circular buffer” scheme itself, it has been found most clear to discuss embodiments of the present invention as if “stationary” buffers were being utilized which can be read to and written from just “as it” they were fixed computer memory locations. However, it is to be borne in mind that the foregoing discussion, although couch to the terms of fixed computer memory buffers, is in a preferred embodiment, implemented via the use of circular buffers by techniques well known to those when the art.
Refer now to FIG. 5 . FIG. 5 will be used in conjunction with FIG. 4 to illustrate an embodiment of the present invention which will alleviate the problems associated with a PCM output buffer, discussed in relation to FIG. 1 above. FIG. 5 constitutes a high-level logic flowchart which depicts an embodiment of the present invention. Method step 500 illustrates the start of the process, which is an entry point where DSP 410 is reset, and which equates to the “powering up” of CDMA voice coding subsystem 400 .
Method step 402 depicts that CDMA voice coding subsystem 400 creates working Buffer A 404 and storage Buffer B 406 , initially of equal size which in one embodiment equates to working Buffer A 404 and storage Buffer B 406 each being of a size capable of holding exactly 160 PCM samples.
Method step 504 illustrates the initialization of an index which points to the start of storage Buffer B 406 . The index points to a register wherein one PCM data sample is stored. Each time PSTN clock 106 pulses, a PCM data sample is transferred out of a register of storage Buffer B 106 , and the index is incremented; thus, some offset of the index is possible should PSTN clock 106 pulses occur before a first ping of GPS clock 114 is received.
Method step 506 shows an inquiry as to whether semi-autonomous unit 402 has received a signal correspondent to a first ping of a GPS clock 114 . If no signal correspondent to a first ping of a GPS clock 114 has been received, the process returns to method step 506 . However, if a signal correspondent to a first ping of a GPS clock 114 has been received, method step 508 depicts both that (1) upon every PSTN clock 106 clock pulse, a PCM sample is transferred onto PCM output stream 122 from storage Buffer B 406 by semi-autonomous unit 402 , and (2) that the index pointing within storage Buffer B 206 is incremented (which will be done in time with the pulses of PSTN clock 106 ). That is, as storage buffer B 406 is emptied, the index is incrementing as the PCM samples are taken from working Buffer B 406 (that is, the index is being advanced even though PCM samples are not being transferred from storage Buffer B 406 ).
Method step 510 depicts that subsequent to the loading of a PCM sample out of, and incrementing of the index pointing to, storage Buffer B 406 , a determination is made as to (1) whether the index pointing within storage Buffer B 406 indicates that the last register of the currently-set storage area of storage Buffer B 406 has been reached and the data within that register transferred out of the register, or (2) whether a signal corresponding to a GPS clock 114 ping has been received. If neither condition is satisfied, the process proceeds to method step 508 and semi-autonomous unit 402 continues transferring PCM samples out of storage Buffer B 406 . However, in the event that either the last register of the currently-set storage area of storage Buffer B 206 has been reached and the data within that register transferred, or that a signal correspondent to a GPS clock 114 ping has been received, the process proceeds to method step 512 .
Method step 512 depicts that an inquiry is made as to whether the last register of the currently-set storage area of storage Buffer B 406 has been reached and the data therein transferred out (i.e., is the index pointing at a register beyond the defined end of specified storage of storage Buffer B 406 ). In the event that the last register of the currently-set storage area of storage Buffer B 406 has been reached and the data therein transferred out, the process proceeds to method step 514 wherein it is depicted that semi-autonomous unit 402 retrieves and augments (by either eliminating a number of the last samples in the data from storage Buffer B 406 if the number of samples is too great, or duplicating the last samples in the data from storage Buffer B 406 if the number of samples is too few) the contents of working Buffer A 404 such that the total data block size is correct for storage Buffer B 406 (it being understood that if the size of storage Buffer B 406 is the same as working Buffer A 404 , then no augmentation is necessary), and thereafter transfers the (possibly augmented) contents of working Buffer A 404 into storage Buffer B 406 .
Data having been transferred from working Buffer A 404 into storage Buffer B 406 , method step 516 illustrates that the index is set to the start of storage buffer B 406 so that it can be reemptied. Thereafter, method step 518 indicates that DSP 410 is to utilize CDMA packet-PCM sample decoder 420 to decode a CDMA packet and to place the decoded PCM samples into working Buffer A 404 . Thereafter, the process proceeds to method step 520 .
Returning to the inquiry of method step 512 , in the event that the last register of the currently-set storage area of storage Buffer B 406 has not been reached and the data therein transferred out, the process proceeds to method step 520 which shows the determination as to whether a signal correspondent to a ping of GPS clock 114 has been received subsequent to that discussed in method step 510 . In the event that another signal correspondent to a ping of GPS clock 114 has not been received, the process returns to method step 508 . In the event that another signal correspondent to a ping of GPS clock 114 has been received, the process proceeds to method step 522 .
Method step 522 depicts that the current value of the index pointing within storage Buffer B 406 index is checked to see if the index is equal to the initialized value (recalling that the index is incremented every time a PCM sample is transferred out of storage Buffer B 406 , this the value to which it was set in method step 504 , provided that the index is set to “wrap,” or reset to the initial index value once the last buffer storage register of the currently-set storage area of storage Buffer B 406 has been cleared). If the index is equal to the initialized value, the process proceeds to method step 526 which illustrates that the defined storage area of storage Buffer B 406 is set to its original size.
If the index is not equal to the initialized value, then it is known that a slippage occurred and that the currently-set size of the storage area of storage Buffer B 406 is not correct, so method step 524 shows that the storage area of storage Buffer B 406 is changed so that it equates to the actual number of samples received between the last two signals correspondent to the last two GPS clock 114 pings; that is, the storage buffer is adjusted so that the index will hit its target value (i.e., there will be no slippage) when the next signal correspondent to ping of GPS clock B 114 is received—if the index is behind, the buffer size will be increased, and if the index is ahead, the buffer size will be decreased.
While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention. | A method and system for avoiding data loss in communications systems. The method and system achieve their objects via communications equipment adapted to do the following: designate a first data-producing system controlled by a first clock; designate a second data-producing system controlled by a second clock; record a timing mismatch between the first clock and the second clock; and dynamically adjust data flow between the first and the second system in response to the recorded timing mismatch. | 7 |
FIELD OF THE INVENTION
The present invention belongs to the field of printing control technology, especially relates to a printing control method for reducing printing memory requirement.
BACKGROUND OF THE INVENTION
In the prior art, the workflow of printing a page by using a conventional raster print device comprises three steps: receiving data to be printed from a host; rasterizing the data to a raster bitmap; and transmitting the raster bitmap to a print engine to output.
The raster bitmap must be transmitted to a print engine at a constant speed in some raster print devices like a laser printer because the raster bitmap must be transferred from the print engine at a constant speed to a laser drum. Once the raster bitmap can not be transmitted to the print engine in time, a so-called “print overrun” occurs to block the page from being outputted correctly onto a piece of paper.
Generally, printing control methods used for the raster print devices in which the raster bitmap are transmitted to the print engine at a constant speed are as follows.
(1) A page is pre-rasterized into the raster bitmap and the raster bitmap are stored in a memory for printing. In this method, the print overrun does not surely occur because the raster bitmap are stored in the memory. However, the shortcoming of this method is that raster print devices with high resolution generally need a large memory. So do Color printers. For example, to store a CMYK color page of A4 with 600 DPI, a memory about 16 MB is needed. This may increase the cost greatly. Furthermore, according to this method, the printing can be started only after the rasterization of a whole page is finished, resulting in reduction of printing speed.
(2) Another known method is dividing a page into multiple bands. According to the method, data of a page are interpreted as an intermediate format arranged in bands, which are easily transformed to the final raster bitmap and occupy much less memory than the raster bitmap of the same page do. The printing can be started after one band is rasterized. As the rasterized band is printed, the raster bitmap of the next band are generated. This method can increase the printing speed and reduce the memory requirement for storing the raster bitmap of a whole page. However, it is a shortcoming of this method that, if the data of a certain band is too complicated to be fully rasterized before the printing of the preceding band is completed, “print overrun” will occur and the page cannot be correctly outputted.
In order to prevent the print overrun, a known solution is pre-counting the rasterizing time required by each of bands. If one or more bands need more time for rasterization separately than the printing time of the preceding band, the bands will be pre-rasterized before printing the page. This solution eliminates the print overrun, but its disadvantage is that the memory is occupied by the raster bitmap of those pre-rasterized bands, resulting in increasing the memory requirement and the cost of the controller.
To address the issue, a lot of improvements are proposed. For example, U.S. Pat. No. 5,129,049 owned by H.P. Company provides a method, in which, if the content of a certain band is very simple or the band have been pre-rasterized, printing the band needs less time than the time for rasterizing one band and an idle time occurs. The idle time could be used for rasterizing the next band. In this way, if the next band needs more time for rasterization, the next band will not need pre-rasterization. Therefore, number of pre-rasterized bands can be reduced to a certain extent. However, this known method uses the idle time of the immediate preceding band only, without utilizing the idle time of all simple bands and idle time of all pre-rasterized bands. Thus, the method fails to minimize number of the bands needing to be pre-rasterized and the printing memory requirement cannot be reduced significantly.
SUMMARY OF THE INVENTION
To overcome the shortcomings of the prior art, the present invention is to provide a printing control method capable of reduction of the printing memory requirement. According to the method, the idle time of rasterization of all simple bands and all pre-rasterized bands is fully used for mastering those complicated bands in the process of printing so as to minimize the bands requiring to be pre-rasterized before printing. Thus, the memory requirement of a complicated page is reduced accordingly.
In order to accomplish the above object, the technical solution used in the present invention is a printing control method for reducing printing memory requirement, comprising the following steps:
(A) receiving print data from a host through an interface;
(B) determining the number of bands of each page to be divided, and the printing time length (TP) of each band, in light of the page, size, the printing speed, and so on;
(C) interpreting the print data to be intermediate format data corresponding to each band;
(D) computing the rasterizing time length (TR) for rasterizing each band in the form of the intermediate format data;
(E) defining each band whose printing time length (TP) is less than its rasterizing time length (TR) as a complicated band;
(F) defining each band whose printing time length (TP) is larger than or equal to its rasterizing time length (TR) as a simple band;
(G) determining start timing of rasterization of each band, further comprising:
(1) initializing the start timing of printing of each band as the result arising from multiplying TP and the value of said respective band number minus 1, wherein the TP refers to the necessary printing time length of one band; (2) setting end timing of rasterization of each band as the start timing of printing the same band, wherein the start timing of rasterization of each simple band is set as a result of the end timing of rasterization of the same band minus the rasterizing time length TR for rasterizing the same band; (3) initializing printing idle time length of each band as the printing time length (TP) of respective band; (4) subtracting time length occupied by rasterization of each simple band except for the first band from the printing idle time length, wherein a concrete method is that the rasterizing time length of a certain band is subtracted from the printing idle time length of a previous band; (5) turning to the step (10) if unmarked complicated bands do not exist; (6) computing the start timing of rasterization of each unmarked complicated band; (7) selecting the band which has the maximal start timing of rasterization and is an unmarked band as an operating band, wherein if the start timing of rasterization of the operating band is less than 0 the step (G) is ended; (8) updating the end timing of rasterization of the operating band as the band number of the last band prior to the operating band, whose printing idle time length is not equal to 0 and marking the operating band; (9) removing the time length occupied by rasterization of the operating band from a printing idle time length information and turning to the step (5); (10) updating the start timing of rasterization of each complicated band;
(H) starting a printing task and starting to print the page until the end of the printing.
Further, a method of updating the start timing of rasterization of each complicated band in the step (10) of the step (G) comprises the steps of:
(1) setting the start timing of rasterization of all the unmarked complicated bands as −1 and marking all the unmarked complicated bands as bands to be pretreated;
(2) initializing the printing idle time length of each band as the printing time of respective band;
(3) subtracting the time length occupied by rasterization of each simple band except for the first band from the printing idle time length, wherein a concrete method is that the rasterizing time length of a certain band is subtracted from the printing idle time length of the previous band;
(4) ending the step (10) if marked complicated bands do not exist, otherwise, selecting the band which has the maximal value of end timing of rasterization from those marked complicated bands as the operating band;
(5) computing the start timing of rasterization of the operating band; and
(6) removing the time length occupied by rasterization of the operating band from the printing idle time length and a mark of the operating band and turning to the step (4).
Further, computing the start timing of rasterization of one band in the step (6) of the step (G) and the step (5) of the step (10) of the step (G) comprises the following steps, the band to be initialized is named the operating band herein:
(a) setting a required time length as the time length for rasterizing the operating band and setting a current band as the operating band;
(b) judging whether the band number of the current band is less than 2, wherein if yes, the operating band must be pretreated, the start timing of rasterization of the operating band is set as −1 and the step (6) of claim 1 or the step (5) of claim 3 is ended, if not, a next step is carried out;
(c) subtracting the printing idle time length of the band which immediately precedes to the current band from the required time length;
(d) setting the band which immediately precedes the current band as a new current band and turning to the step (b) if the required time length is larger than 0, and carrying out the next step if the required time length is not larger than 0; and
(e) setting the start timing of printing an above preceding band plus the absolute value of the required time length as the start timing of rasterization of the operating band.
Further, removing the time length occupied by rasterization of the operating band in the step (9) of the step (G) and the step (6) of the step (10) of the step (G) comprises the following steps:
(a) setting a required time length as the time length for rasterizing the operating band and setting a current band as the operating band;
(b) subtracting the printing idle time length of the band which immediately precedes the current band from the required time length;
(c) setting the printing idle time length of the band which immediately precedes the current band as 0 and the band which immediately precedes the current band as a new current band and turning to the step (b) if the required time length is larger than 0, and carrying out the next step if the required time length is not larger than 0; and
(d) setting the idle time length of the band which immediately precedes the current band as the absolute value of the required time length.
Further, the printing task in the step (H) is used mainly for operating printing work, the printing task comprises the steps of:
(1) pre-rasterizing all the bands whose start timing of rasterization is −1;
(2) setting up an auxiliary task if there is any complicated band whose start timing of rasterization is larger than or equal to 0, wherein the auxiliary task has a lower priority than the main printing task, each complicated band is started to be rasterized in the auxiliary task at the start timing of rasterization of the relevant complicated band;
(3) rasterizing Band 1 and transmitting the bitmap to a print buffer;
(4) starting a print engine to print the band which is currently in the print buffer;
(5) rasterizing a next band in the main printing task till the start timing of its rasterization if the next band to be printed is the simple band;
(6) obtaining the raster bitmap of the next band and transmitting the raster bitmap to the print buffer;
(7) starting to print the next band by the print engine; and
(8) repeating the steps (5, 6 and 7) until the page is completely printed.
The present invention has the following effects. According to the printing control method of the present invention, making full use of the idle time length of rasterization of all the simple bands and pre-rasterized bands, complicated bands can be rasterized in the printing process to minimize the bands which is to be pre-rasterized before the beginning of printing so that the printing memory requirement is reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a printing control method;
FIG. 2 is a schematic diagram showing a page to be printed and how to divide the page into N bands;
FIG. 3 is a flowchart of printing steps;
FIG. 4 is a flowchart showing how to determine the rasterizing time according to the present invention;
FIG. 5 is a flowchart showing the determination of the start timing of rasterization for a band;
FIG. 6 is a flowchart showing that the time spent by rasterizing a current band is removed from an idle time length;
FIG. 7 is a flowchart showing how to update a start timing of rasterization of each band;
FIG. 8 is a flowchart of the main printing task; and
FIG. 9 schematically shows running a main printing task in parallel with running an auxiliary printing task in the printing process.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, a detailed description of the present invention will be given with reference to the appended drawings.
FIG. 1 shows the printing control method according to the present invention as well a laser printer comprising a host interface 11 , a CPU 13 , a ROM 16 , a DRAM 12 , a print control unit 14 , a print engine 15 , etc. The host interface 11 is configured to be a parallel interface, a network, a USB or the like. The printer receives the data to be printed from a computer 10 through the host interface 11 . The CPU 13 is a central control unit of the printer. The ROM 16 is used for storing programs, fonts, etc. The DRAM 12 provides a space for running the programs and functions as a buffer for buffering a raster bitmap. The print control unit 14 controls the print engine 15 to print the raster bitmap on paper.
As shown in FIG. 2 , a page to be printed can be logically divided into multiple bands, like N bands (N≧2), along the movement direction of a piece of paper. Each band comprises identical number of scanning lines, such as M lines. If the total number of scanning lines of one page is not equal to N*M, the number of the lines of the last band will be less than M, which does not influence the availability of the present invention. Assuming that the time length for printing the whole page is T seconds, the time length for printing one band will be TP=T/N. TP is also the time length for generating the raster bitmap of the next band. If the raster bitmap of the next band cannot be fully generated within TP, said “Print Overrun” will occur.
As shown in FIG. 3 , the present invention provides a printing control method capable of reducing printing memory requirement.
Specifically, the printer receives page content described with a page description language such as PostScript or PCL from the computer 10 through the host interface 11 . The received information is stored in the DRAM 12 . The programs stored in the ROM 16 determine, in light of the movement direction of the paper, page size, the printing speed, the memory space of the printer, the performance of the CPU, and so on, how many bands to be divided for the page. For example, N bands are divided for the page. Along the of movement direction of the paper, the divided bands is in turn named as Band 1 , Band 2 , Band 3 , . . . , Band N. Moreover, according to the time length T for printing one page, the time length for printing one band is TP=T/N. Subsequently, the contents (e.g. text, graphics, etc) of the page content are interpreted into a series of simple intermediate format instructions from which the raster bitmap can be easily obtained. These instructions are already stored in respective bands according to respective positions of the band on the page. Usually, the space occupied by the intermediate format instructions of a whole page is much less than that occupied by the raster bitmap.
Next step is to calculate a time length required for rasterizing the intermediate format instructions of each band into the raster bitmap according to the content of the intermediate format instructions of the band. The time length is, e.g. denoted as TR[I] for Band I.
TR(I) is compared with TP. If TP<TR[I], Band I is defined as a complicated band. Otherwise, Band I is defined as a simple band and marked.
Next step is to determine the start timing of rasterization of each band, which will be explained in detail with reference to FIG. 4 .
Finally, a printing task is started and the page is printed, which will be explained with reference to FIG. 6 .
As shown in FIG. 4 , determining the start timing of rasterization of each band comprises the following steps:
(1) initializing the start timing of printing each band, wherein the start timing of printing the first band is marked with 0, and the start timing of any of the rest band is marked with the result arising from multiplying TP and the value of said relevant band number minus 1;
(2) determining the start timing of rasterization of each of simple bands, wherein the end timing (TendRaster) of rasterization of each simple band is set as the start timing of printing the same band. Thus, the end timing (TendRaster) of rasterization of one simple band minus the time length (TR) of rasterizing this band will be the start timing (TbeginRaster) of rasterization of the band;
(3) initializing idle time length information, wherein the idle time length of each band is initialized as the printing time (TP) of respective band, and then the time lengths occupied by rasterization of each of simple bands except for the first band is subtracted from the total idle time lengths. For instance, the time length of rasterizing a certain band is subtracted from the idle time length of the immediate preceding band;
(4) initializing the end timing of rasterization of each complicated band, wherein the end timing of rasterization of a complicated band is initialized as the start timing of printing the same band;
(5) checking whether any complicated band has not been marked. If not, the procedure turns to update the start timing of rasterization of all bands;
(6) initializing the start timing of rasterization of each unmarked complicated band if any, wherein the start timing (TbeginRaster) of rasterization of a band refers to, if all the idle time lengths can be utilized for one band, the timing which is set for ensuring the completion of rasterization of the same band prior to the end timing (TendRaster) of rasterization of the same band, i.e. the latest start timing of rasterization of the band, which will be explained in detail with reference to FIG. 5 ;
(7) selecting a band which has the maximal value of start timing of rasterization from those unmarked bands as an operating band;
(8) turning to update the start timing of rasterization of all bands if the start timing of rasterization of the operating band is less than 0;
(9) otherwise, updating the end timing (TendRaster) of rasterization of the operating band with a band number. The band precedes the operating band but the idle time length of the band is not 0;
(10) marking the operating band; and
(11) updating the idle time length information, wherein the time length occupied by the operating band is removed from the idle time length, as shown in FIG. 6 ; and then turning to the step (5) to check whether any band to be operated exists.
It is determined which bands may be arranged in an auxiliary task. All determined bands to be arranged in the auxiliary task are marked and then the start timing of rasterization of all bands should be updated. Such process is shown in detail in FIG. 7 .
FIG. 5 shows how to determine the start timing of rasterization of the operating band. The detailed steps are as follows:
(1) setting a required time length (Time) as the time length for rasterizing the operating band;
(2) setting a current band as the operating band, and judging whether the band number of the current band is less than 2. If yes, the start timing of rasterization of the operating band is set as −1 and the procedure is ended. If not, the next step is carried out;
(3) subtracting, from the required time length (Time), the idle time length of the band which immediately precedes to the current band; and
(4) judging whether the required time length (Time)<0. If yes, the start timing of printing the above preceding band plus the absolute value of the required time length (Time) is set as the start timing of rasterization of the operating band. If not, the band which immediately precedes the current band is set as a new current band. Then, it is judged whether the new current band number is less than 2 or not. If yes, the start timing of rasterization of the operating band is set as −1 and the procedure is ended. If not, step (3) is repeated.
As shown in FIG. 6 , the operation for removal of the time length for rasterizing the operating band comprises the following steps:
(1) setting a required time length (Time) as the time length for rasterizing the operating band;
(2) setting a current band as the operating band, and subtracting, from the required time length (Time), the idle time length of the band which immediately precedes the current band; and
(3) judging whether the required time length (Time)>0. If the required time length (Time) is less than 0, the idle time length of the band which immediately precedes the current band is set as the absolute value of the required time length (Time) and the procedure is ended. If not, the idle time length of the band which immediately precedes the current band is set as 0, the band which immediately precedes the current band is set as the new current band, and the idle time length of the band which immediately precedes the current band is subtracted from the required time length (Time).
As shown in FIG. 7 , the start timing of rasterization of each complicated band is updated. The unmarked complicated hands are set as bands to be pretreated. The order of rasterization of those marked complicated bands is arranged according to the determined order of end timing of rasterization in FIG. 4 . Each complicated band in the arrangement is rasterized as late as possible, as long as the latter bands have sufficient time to be rasterized. FIG. 7 proposes specific steps:
(1) marking all the unmarked complicated bands as bands to be pretreated and setting their start timing of rasterization as −1;
(2) initializing the idle time length information. In particular, the idle time length of each band is initialized as the printing time (TP) of respective band, and the time length occupied by rasterization of each simple band except for the first band is subtracted from the idle time length. The subtraction is carried out by subtracting the rasterizing time of a certain band from the idle time length of the band which immediately precedes said certain band;
(3) ending this process if there is no marked complicated band, otherwise, going ahead to the next step;
(4) selecting a band which has the maximal value of end timing (TendRaster) of rasterization from those marked complicated bands as an operating band;
(5) computing the start timing of rasterization of the operating band according to FIG. 5 ;
(6) updating the idle time length information and removing the time length occupied by rasterization of the operating band according to FIG. 6 ; and
(7) deleting the mark of the operating band and checking whether any marked complicated band still exists.
As shown in FIG. 8 , the detailed steps of the printing task are as follows:
(1) initializing, wherein all the bands which are marked as bands to be pretreated are pre-rasterized;
(2) setting up an auxiliary task if there is any complicated band which has not been pretreated, wherein the complicated band which has not been pretreated is rasterized in the auxiliary task. The main printing task has a higher priority than the auxiliary task, so the auxiliary task can be only run when the main printing task is idle;
(3) rasterizing Band 1 and transmitting the bitmap to a print buffer, and starting a print engine;
(4) printing the band which is currently in the print buffer; and
(5) judging whether this band being printed is the last band, and ending printing if yes; otherwise, judging whether the next band is a simple band, the next band is rasterized till the start timing of its rasterization if the next band is a simple band, and the raster bitmap are transmitted to the print buffer; if the next band is not a simple band, it is further judged whether the next band is a pretreated complicated band. If it is true, the raster bitmap from the pre-rasterized raster are transmitted to the print raster buffer, otherwise, the raster bitmap are transmitted to the print raster buffers until the band is fully rasterized in the auxiliary task.
FIG. 9 is a simplified example according to the embodiment of the present invention for showing the parallel run of the main printing task, the auxiliary printing task and the print engine in the printing output process.
As shown in FIG. 9 , a page is divided into, e.g. six bands, wherein the first, second and fourth bands are simple bands whose rasterizing time lengths are respectively 0.5 TP, 0.5 TP and 1 TP (TP is the time length for printing one band), and the third, fifth and sixth bands are complicated bands whose rasterizing time lengths are respectively 1.25 TP, 1.25 TP and 3.25 TP. According to the present invention, the sixth band is marked as a pretreated band, the fifth band is started to be rasterized after 1.75 TP in the auxiliary task after the beginning of printing, and the third band is started to be rasterized in the auxiliary task upon starting the printing.
While starting the printing, the main printing task enables an auxiliary printing task to rasterize the third and fifth bands. The auxiliary printing task has a lower priority than the main printing task. The main printing task rasterizes all the non-real-time rasterized bands (i.e. the sixth band) prior to rasterizing the first band.
While the print engine is started to print the first band, the auxiliary printing task is started to rasterize the third band. The auxiliary printing task is suspended after 0.5 TP. At this time, the main printing task is started to rasterize the second band 0.5 TP.
While printing the first band is finished, the rasterization of the second band by the main printing task is also finished. The print engine is started to print the second band and the auxiliary printing task is continued to rasterize the third band. Rasterizing the third band is finished after 1.75 TP. At this time, the auxiliary printing task is started to rasterize the fifth band.
While printing the second band is finished, the main printing task starts the print engine to print the third band. Meanwhile, rasterizing the fourth band is started.
While printing the third band is finished, the main printing task starts the print engine to print the fourth band. Since the fifth band is a complicated band, its rasterization is not implemented in the main printing task. Therefore, the main printing task becomes idle.
While printing the fourth band is finished, the main printing task starts the print engine to print the fifth band. Since the next sixth band is a complicated band, it is not rasterized in the main printing task. Therefore, the main printing task maintains idle.
While printing the fifth band is finished, the main printing task starts the print engine to print the sixth band.
While printing the sixth band is finished, the printing for the page is ended.
As the example shown in FIG. 6 , the printing can be started only after the pre-rasterization of the first, third, fifth and sixth bands in the prior print art. According to the present invention, the printing can be started only after rasterizing the first and sixth bands. The rasterization of the third and fifth bands can be proceeded in the printing process. Therefore, it can reduce the printing memory requirement.
The above description is one embodiment of the present invention and not restrictive to the present invention. For example, although the above is described with reference to laser printers, the invention is adaptive to ink-jet printers with raster bitmaps, phototypesetters with raster bitmaps, and the like. Thus, without departing from the spirit and principle of the present invention, any modifications, substitutions and improvements should be within the scope of the present invention. | The present invention belongs to the field of printing control technology, and is especially one kind of printing control method with reducing printing memory requirement. The available printing technology always needs complicated segment forming gratings in advance and occupying great amount of memory. The printing control method of the present invention includes interpreting the page data as banded intermediate format data, calculating the time for forming grating of each band of the intermediate format data, pre-analyzing the bands with time for forming grating greater than the printing time, and arranging the job of forming grating of the complicated bands in the idle print time as far as possible. The said method can reduce the band number of forming gratings in advance and reduce the printing memory requirement. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to an apparatus for assessing the condition of at least one circulating band, in particular of a water-absorbing dewatering band and/or a transfer band in a papermaking machine.
[0003] 2. Description of the Related Art
[0004] In general, the prior art discloses apparatuses which permit a permeability measurement on the circulating dewatering band. However, such apparatuses have a disadvantage in that they measure a high permeability at holes, cracks or the like, a high permeability being an indication of a satisfactory quality of the dewatering band. Thus, those apparatuses, which measure only the permeability, supply erroneous information about the condition of the quality of the dewatering band, in particular at holes, cracks or the like.
[0005] In addition, the prior art discloses handheld devices for measuring the permeability and handheld devices for measuring the moisture of a dewatering band in a papermaking machine. In using these handheld devices, it is not possible for any continuous monitoring of the permeability and of the moisture of the dewatering band to be carried out during operation. In addition, such handheld devices have only a limited accuracy, with which frequently no satisfactory statements can be made about the condition of the dewatering band. However, in order to be able to ensure a satisfactory quality of a fibrous web to be produced, it is necessary to be able to measure the permeability and the moisture of the dewatering band during operation, the quality of the fibrous web to be produced also depends on the quality of the permeability measurement and the moisture measurement.
SUMMARY OF THE INVENTION
[0006] The object of the present invention is to improve the reliability and accuracy in assessing the condition of the at least one circulating band by way of an apparatus that measures the permeability of at least one circulating band.
[0007] The present invention achieves the objective by way of an apparatus having a device for measuring the moisture contained in the at least one band. Thus, the apparatus according to the invention supplies further information about the state of the at least one circulating band. If, therefore, a high permeability is measured at a hole, at a crack or the like, a moisture level which is very low will be detected at the hole, at the crack or the like. From the simultaneous presence of a high permeability and a very low moisture, it is then possible to conclude that there is a hole, a crack or the like. Since the apparatus, according to the present invention, permits the measurement of the permeability and of the presence of moisture during operation, it is able to continuously supply accurate information about the instantaneous state of the at least one circulating band. Since continuous monitoring of the condition of the at least one circulating band is possible, the production of a high quality fibrous web is ensured.
[0008] It is possible to carry out the moisture measurement simultaneously or with a time offset in relation to the measurement of the permeability. However, the time interval between the permeability measurement and the moisture measurement should be no more than five hours, since the at least one circulating band changes over time. If the time interval between the permeability measurement and the moisture measurement is too great, soiling on the at least one circulating band or wear of the at least one circulating band can distort the information obtained.
[0009] If the moisture measurement and the measurement of the permeability are carried out at the same point on the at least one circulating band, very accurate information, with regard to the condition of the at least one circulating band, can be obtained. For this purpose, the measurement points for the permeability and moisture measurement are located one after another as viewed in the band running direction. The distances between the two measurement points are expediently relatively short so that, taking the high band speeds into account, a virtually simultaneous measurement of the two measured values can be carried out.
[0010] However, it is also possible to carry out the moisture measurement and the measurement of the permeability at different points of the at least one circulating band. Then, for example, the two measuring points can be arranged transversely with respect to the band running direction; in this case, too, the distances between the two measurement points should be relatively short, in order to obtain the most reliable information possible about the condition of the at least one circulating band. If the moisture and the permeability are measured at different points of the at least one circulating band and the distances between the two measuring points are relatively short, it is possible, by computation, to associate one measuring point, for example, the measuring point at which the moisture is measured, with the other measuring point, for example, the measuring point at which the permeability is measured.
[0011] The apparatus, according to the present invention can advantageously also have a device for measuring the band temperature. Thus, during operation, the temperature of the at least one circulating band can be measured. The band temperature likewise supplies information about the condition of the at least one circulating band. For example, the band temperature at soiled points, holes, cracks and the like differs from the band temperature at clean or fault-free points of the band. In addition, the measured band temperature can be useful for controlling the temperature of a measuring fluid needed for the permeability measurement.
[0012] In a development of the present invention, the apparatus, on a reel-up, has a device for the measurement of moisture of a material web, in particular a fibrous web. It is likewise possible for the apparatus, according to the present invention, to have, after a press section, a moisture measurement device of the material web, in particular the fibrous web. If the at least one circulating band is a dewatering band, its condition directly affects the moisture of the material web to be produced. Thus, the measured moisture of the material web, at the reel-up and/or in the press section, provides information about the condition of the at least one circulating band.
[0013] In addition, the apparatus can be provided with a device for determining the grammage of the material web, in particular the fibrous web. If the at least one circulating band is a dewatering band, its quality also directly affects the grammage of the material web to be produced. Thus, the grammage of the material web also provides information about the condition of the at least one circulating band.
[0014] Since the at least one circulating band discharges heat to the machine house surroundings during operation, the distribution of the machine house temperature along its width supplies information about its condition. At the points at which the at least one circulating band is highly soiled or has holes, cracks or the like, the heat emission varies. In addition, by using the device for measuring the machine house temperature and the device for measuring the band temperature, the difference between the two temperatures, along the width of the at the least one circulating band, can be determined. From this information statements about the condition of the band can be made. The device for measuring the machine house temperature can expediently be arranged on a cleaning assembly for cleaning the at least one circulating band.
[0015] Since the thickness of the at least one circulating band additionally permits a statement about its condition, the apparatus can have a device for measuring the thickness of the at least one circulating band. Deposits increase its thickness, whereas band abrasion reduces its thickness.
[0016] The condition of the at least one circulating band is also directly related to the tensile stress prevailing in it. It is therefore expedient to equip the apparatus with a device for measuring the tensile stress prevailing in the at least one circulating band. High band abrasion, soiling on the at least one circulating band and other influences can increase the tensile stress.
[0017] In one embodiment of the present invention, the apparatus is equipped with a device for measuring the filler content of the material web. The fillers contained in the material web can block up the pores of the at least one circulating band. Thus, from the filler content of the material web, it is possible to draw conclusions about a level of soiling and/or about an increase in the soiling of the at least one circulating band.
[0018] In a further embodiment of the present invention, the apparatus has a device for measuring a pressure, which prevails in a nip between two rolls, and/or a device for measuring the thickness of the material web. Since at least one circulating band, as a dewatering band, also affects the thickness of the material web to be produced, the level of the pressure, which prevails in the nip between two rolls, also depends on its condition. Thus, the pressure in the nip between two rolls supplies information about the condition of the at least one circulating band. The measurement of the thickness of the material web can advantageously be made by measuring the web suction which prevails in the material web.
[0019] In a further embodiment of the present invention, the apparatus has a device for measuring at least one surface property of the material web, in particular the roughness, the soiling (pigments, stock) and the like.
[0020] In yet another embodiment of the present invention, the apparatus has a steam blower box and/or a moistener. The steam outlet volume and/or moisture volume is regulated as a function of the condition of the at least one circulating band along the material web width. Thus, by using the steam blower box and/or the moistener, the quality of the material web to be produced can be evened out if this has been impaired by a worsening of the state of the at least one band. However, by using the steam blower box and/or the moistener, it is also possible to affect the condition of the at least one band.
[0021] In addition, the mixture ratio of a fiber and filler suspension and a dilution stream at a flow box, along the width of an outlet opening of a nozzle from which the mixture emerges, can be regulated as a function of the condition of the at least one circulating band along the material web width. Since the fibers and fillers contained in the material web to be produced can soil the at least one circulating band, the mixture ratio can be changed by increasing the dilution stream in such a way that the soiling of the at least one circulating band is reduced.
[0022] In addition, the present invention relates to a method for assessing the condition of the at least one circulating band. In particular of the water-absorbing dewatering band and/or transfer band in the papermaking machine. The permeability of the at least one circulating band is measured, and the moisture contained in the at least one circulating band is also measured. In addition, it is possible to measure the band temperature with the method according to the present invention.
[0023] Furthermore, by using the method according to the present invention, the moisture of the material web at the reel-up, and/or the moisture of the material web after the press section, and/or the grammage of the material web, and/or the pressure in the nip between two rolls, and/or the machine house temperature prevailing along the material web width, and/or the thickness of the at least one circulating band, and/or the tensile stress prevailing in the at least one circulating band and/or the filler content of the material web, and/or the thickness of the material web can be measured.
[0024] By using the method according to the present invention, the steam outlet volume, emerging from the steamer blower box, can also be regulated as a function of the condition of the at least one circulating band along the material web width.
[0025] It is likewise possible, by using the method of the present invention, for the moisture volume, emerging from the moistener, to be regulated as a function of the condition of the at least one band along the material web width. Furthermore, the mixture ratio of the fiber and filler suspension and the dilution stream at the flow box, along the width of the outlet opening of the nozzle from which the mixture emerges, can be regulated as a function of the condition of the at least one band along the material web width.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:
[0027] FIG. 1 is shows a schematical side view of an embodiment of a papermaking machine of the present invention; and
[0028] FIG. 2 is shows a schematical side view of a press section of the papermaking machine of FIG. 1 .
[0029] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates one preferred embodiment of the invention, in one form, and such exemplification is not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
[0030] Referring now to the drawings, and more particularly to FIG. 1 , which shows a side view of a papermaking machine 10 , with which a material web 11 is produced. Material web 11 can be a paper, board or tissue or other fibrous web. Papermaking machine 10 has various circulating bands 12 , 13 , 14 and 15 . In the example illustrated, band 12 performs the function of a first top felt picking up material web 11 , band 13 the function of a first bottom felt, band 14 the function of a second top felt and band 15 the function of a second bottom felt. However, band 15 can also be a transfer band.
[0031] Now, additionally referring to FIG. 2 , bands 12 , 13 , 14 and 15 are provided with measuring devices 20 , 21 , 22 and 23 . Measuring devices 20 , 21 , 22 and 23 are equipped with devices, not shown specifically here, for measuring the permeability and/or the moisture of bands 12 , 13 , 14 and 15 . In this way, reliable information can be obtained about the condition of bands 12 , 13 , 14 and 15 . If a high permeability is measured, this can indicate bands 12 , 13 , 14 or 15 are clean. However, it is also possible for bands 12 , 13 , 14 or 15 to have a hole, a crack or the like, so that in this case, too, a high permeability is measured. In order to rule out misinterpretations, which can result from the permeability measurement, the moisture measurement is additionally carried out. In order that the measuring result supplies reliable information, it is expedient to carry out the moisture measurement and the permeability measurement at the same measuring point, or at measuring points located close beside one another, on circulating bands 12 , 13 , 14 or 15 . If a high permeability is measured in the permeability measurement and a very low moisture is measured in the moisture measurement, then these results allow the conclusion that there is a hole or a crack or the like in bands 12 , 13 , 14 or 15 . Thus, the moisture measurement is an expedient supplement to the permeability measurement in order to assess the condition of bands 12 , 13 , 14 or 15 . Apart from holes, cracks and the like, the soiling of bands 12 , 13 , 14 or 15 can also be detected by way of the combined permeability and moisture measurement. Then, by way of conditioning devices 25 , 26 , 27 and 28 , soiled bands 12 , 13 , 14 or 15 can be cleaned. For this purpose, measuring devices 20 , 21 , 22 and 23 are connected via measuring signal lines 19 to an evaluation unit 16 , which activates conditioning devices 25 , 26 , 27 or 28 as required in order to clean bands 12 , 13 , 14 or 15 . If band 15 is a transfer band, conditioning device 28 is omitted. In addition, a device for measuring the temperature of bands 12 , 13 , 14 and 15 is provided in measuring devices 20 , 21 , 22 and 23 .
[0032] At the end of a press section 17 , papermaking machine 10 has a device 18 for measuring the moisture of material web 11 and, on a reel-up 100 , a measuring device 101 is positioned for measuring the moisture of material web 11 . The moisture measured with devices 18 and 101 provides information about the condition of bands 12 , 13 , 14 and 15 . The moisture value measured by devices 18 and 101 is transmitted to an evaluation unit 16 by way of measuring signal lines 19 .
[0033] In evaluation unit 16 , all the measured values, including the measured values transmitted by measuring devices not specifically illustrated here, are evaluated and, if required, conditioning devices 25 , 26 , 27 and 28 are activated. In addition, a flow box 103 and a steam blower box 104 can be regulated by way of actuating signal lines 102 in accordance with the condition of bands 12 , 13 , 14 and 15 .
[0034] In the case of the regulation of flow box 103 , the mixture ratio of a fiber and filler suspension and a dilution stream at flow box 103 , along the width of an outlet opening, not shown here, of a nozzle from which the mixture emerges, is regulated as a function of the condition of bands 12 , 13 , 14 and 15 along the width of material web 11 . In order to avoid soiling of bands 12 , 13 , 14 and 15 by the fibrous stock and fillers, the dilution stream is increased during this regulation procedure.
[0035] In the case of the regulation of steam blower box 104 , the steam outlet volume is regulated as a function of the condition of bands 12 , 13 , 14 and 15 . In this way, with steam blower box 104 , the quality of the material web to be produced can be balanced out if the latter has been impaired by a worsening of the condition of bands 12 , 13 , 14 and 15 . In addition, the state of bands 12 , 13 , 14 and 15 can be acted on with steam blower box 104 .
[0036] Thus, by way of the apparatus according to the present invention and by way of the method that can be carried out therewith, the measured values interacting with one another can be registered and evaluated, in order to be able to make appropriate changes in the process of the material web production and/or the conditioning of bands 12 , 13 , 14 and 15 . By way of these appropriate changes, bands 12 , 13 , 14 and 15 are kept in a state which ensures the production of a qualitatively satisfactory material web.
[0037] While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | The invention relates to an apparatus for assessing the condition of at least one circulating band, in particular of a water-absorbing dewatering band and/or a transfer band in a papermaking machine, having a device for measuring the permeability of the at least one circulating band. The invention reliably and accuractly assesses the condition of the at least one circulating band. The apparatus according to the invention is additionally equipped with a device for measuring the moisture contained in the at least one circulating band. | 3 |
This is a continuation of application Ser. No. 934,022 filed Aug. 16, 1978, abandoned, which is in turn a division of Ser. No. 873,896, filed Jan. 31, 1978, now U.S. Pat. No. 4,222,864 issued on Sept. 16, 1980.
FIELD OF THE INVENTION
The invention relates to a drum-type screening machine having a tubular screening drum in which a centrifuging rotor is arranged.
Such drum-type screening machines are used very often for the shifting of fine products. In grain milling for example they are used for control sifting of the finished products, and have already been proposed as screening apparatus for individual passages.
In such cases, relatively fine screening cloths are used, which can very easily be damaged because of the centrifuging action by foreign bodies such as pieces of wood, metal, screws and the like.
The safety devices used hitherto have considerable disadvantages. A magnet can retain only magnetisable articles. A swing-out device before the machine involves a loss of product and also does not always operate reliably.
STATEMENT OF PRIOR ART
In a simple, slowly rotating screening drum for coarse products (French Pat. No. 1 371 955 of 1964) a screening tube of relatively small diameter and provided with coarse perforations is fixed coaxially on the screening drum. But such a screening tube requires a separate outlet, which involves great complication in the construction of the housing in the case of a drum-type screening machine for fine products, and makes it impossible to arrange a centrifuging rotor independent of the screening drum.
In an early proposal (German Pat. No. 33328 of 1885) grinding stock falls from the inlet of a screening machine into a screw conveyor and thence is conveyed to a basket having a conical portion of wire. Conveyor blades propel the grinding stock through the wire weave. A stop plate forms the bottom of the basket and has a conical flange which returns the grinding stock to the entry region of the screen. The basket collects larger foreign bodies and has room to store then clear of the conveyor blades. Access to the basket for removal of accumulated foreign bodies is difficult or impossible without major dismantling of the machine, there being a port in an end cover of the screen support, a closure to that part, and no means of access to that cover. Moreover the provision of a door for periodic removal of the foreign bodies would lead to construction problems in the vicinity of the main bearing.
SHORT DESCRIPTION OF THE INVENTION
The invention makes it possible to obviate these disadvantages in a surprisingly simple manner. The invention provides a drum type screening machine comprising a tubular screening drum, a shaft extending axially with respect to said drum, a centrifuging rotor mounted on said shaft for rotation within said drum, a feed inlet to said drum near an entry region of said drum, a perforate retaining element mounted on said shaft intermediate said feed inlet and said entry region, said screening drum having screening perforations and said retaining element having retaining perforations, said retaining perforations being larger than said screening perforations; and said retaining element having an access aperture therein and a movable closure element and means for holding said closure element movably in position to close said access aperture.
Of course the holes of the retaining element have smaller dimensions than the foreign bodies which have to be held back.
According to a further feature the retaining element can comprise a perforated plate for example a perforated metal plate or coarse screening cloth. Preferably dense perforation is provided, i.e. with a large free throughflow section. For easily flowing products e.g. flour and semolina, a hole diameter of about 2.5 mm is advisable. For poorly flowing mill products e.g. filter flour, a hole diameter of 4 mm is suitable. If the perforated plate is used by itself, a very simple construction is obtained which is quite satisfactory for straightforward uses. But it has the disadvantages that the retained foreign bodies tumble about in the machine housing and cause wear therein. When there are large foreign bodies to be dealt with, the shape-closing accuracy of the disc is not guaranteed, since the disc can fairly easily be damaged.
Therefore, it is advisable to secure on the perforated plate a rim which extends in the direction of the inlet and which forms, together with the perforated plate, a basket. Because of the centrifuging effect, the foreign bodies remain lying on the rim, and there is no relative movement with regard to the basket. Thus, the wear and damage problems are solved.
It is advantageous also to perforate the rim, so that at the end of a working period the basket can be completely emptied by rotational movement of the centrifuging motor. Since the rim is at a small spacing from the housing of the machine and from the screen fabric, during operation the perforations are able to allow a continual flow of fresh product through the narrow annular gap.
If the retaining is secured by spokes on the shaft of the centrifuging rotor, and if the spokes are secured preferably on a hub, which itself is secured to the shaft, simple constructions are obtained. The spokes may, at least in part, be inclined relatively to the alignment of the centrifuging rotor and be constructed as feed or conveying blades.
If the perforated plate is arranged at an inclination to the axis of the centrifuging rotor to act as a kind of swash plate, the product is pulsed to and fro at the disc, which improves the transfer to the screen chamber. This also applies if the rim of the basket is conical in shape.
A simple construction is obtained if the closure element is a movable segment. The segment can be arranged to be axially displaceable at the inlet side of the perforated plate, and could be secured to a hub adapted to be displaced on the shaft of the centrifuging rotor. A compression spring can be provided between the fixed hub of the retaining element and the displaceable hub of the segment, for pressing the segment towards the perforated plate.
If locating pins to locate the sides of the segment are secured on the retaining element, the locating pins being shorter than the opening travel of the segment, the segment can be displaced first and then turned, which facilitates the removal of the foreign bodies.
The spokes can be formed with recesses in order to allow the displacement of the segment.
Hitherto the normal working life of the screening cloth has not been fully utilised, since it is usually damaged by foreign bodies before it wears out. This kind of damage is obviated when using the drum-type screening machine provided by the invention. But as a result of the normal wear on the screening cloth, which will now be experienced, the tension of the screening cloth will vary and this will considerably modify the screening effect. Therefore, it is necessary to be able to modify the tension of the screening cloth quickly. In a known drum-type screening machine (German Pat. No. 2 129 952) its screening drum is provided with a screening cloth which can be arranged on two rings which are connected by bars to be at an adjustable distance apart, the first ring can be fixed to a closure part e.g. a cover which itself can be secured on the housing of the machine, the second ring being arranged to be slidable on a ring on the housing, and in the region of the closure part the bars are each provided with a screwthread. The screening drum can be removed relatively quickly and comfortably from the housing of the drum-type screening machine, and the screen tension can then be modified relatively easily. But this required a series of operations and the working of the machine is interrupted. It is possible to obviate these disadvantages, according to a feature of the invention, by providing the screening drum with an axially effective tensioning device which in the fitted state of the screening drum can be adjusted from the outside during operation.
Thus the invention also provides a drum type screening machine having a tubular screening drum, said drum comprising a first ring and a second ring and a screening cloth supported thereby and a plurality of tensioning bars holding said rings at an adjustable distance from each other, and said machine having a machine housing, a housing end member, said first ring being supported within said end member, support means within said housing adapted to support said second ring, each said bar having a first screwthread means at an end portion thereof, second screw thread means on one of said rings fast against axial movement relative to said one of said rings, said first and second screw thread means being in operative screw engagement, and turning means to cause relative rotation between said first and second screw means thereby to vary the distance between said rings.
In a particularly advantageous constructional form said first screw thread means on said bar is an exterior male thread and said second screw thread means is an internal female thread in a nut and said nut is captive with said one of said rings, the nut being in a fixed axial position relatively to the housing of the machine in the completely assembled state. Thus the position of the bars and thus the tension of the screening cloth can be modified during operation.
The simplest construction is obtained if the nut is fast against rotation in the completely assembled state. Advantageously the nut is provided with an external screwthread which can be screwed into a screwthreaded bore, the axial position of which is defined by the closure part. The screwthreaded bore is preferably arranged in the first ring itself or in a flange secured to the first ring. The nut can be of simple construction, consisting of a sleeve, having the external screwthread and of a head on the said sleeve, said head being provided with an engagement surface and being situated at the internal side of the machine. The sleeve can project outside the machine to receive a locknut, thereby guarding against turning movement.
If the bar is arranged on the second ring to be rotatable but axially fixed and is provided outside of the closure part with an engagement surface e.g. a hexagon, the tension of the screening cloth can be adjusted from the outside. But it is a better construction if the screwthread is situated on a screwthreaded sleeve which is rotatable but axially fixed on the bar, the bar being fixed fast against rotation. To achieve this, the bar can be screwed into the second ring or into a flange secured on the second ring, and secured by a locknut arranged at the inside.
The screwthreaded sleeve can advantageously be provided with an engagement surface, e.g. a hexagon portion.
If the equipment of the drum-type screening machine comprises a tubular hexagonal box spanner for turning the engagement surface, and is provided with a slot and a scale, the axial position of the engagement surface can be monitored so that all the bars can be adjusted equally.
If elastic buffer or cushion elements for the screening cloth are carried on the bars outside the screening drum, the pulsation of the screening cloth which takes place because of the centrifuging action can be influenced. Where individual buffer elements abut on the screening cloth the free vibration length is permanently reduced. Where individual buffer elements are spaced from the screening cloth, the free vibration length is reduced only when the buffer elements abut the cloth. To render the action of the buffer elements more specific, the screening cloth can be provided with a supporting hoop, preferably internally, in an axial position which corresponds to that of the buffer element in question.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be explained with reference to the embodiment and two modifications thereof shown in the drawings wherein:
FIG. 1 shows the machine in longitudinal section taken on the line I--I of FIG. 2;
FIG. 2 is a side view as seen from the outlet side in the direction of the arrow II in FIG. 1;
FIG. 3 shows a section on a larger scale through the inlet portion of the machine along the I--I of FIG. 2 and shows the retaining element and the inlet-region of the centrifuging rotor and of the screening drum;
FIG. 4 shows a section through a modified form of retaining element on the same scale as in FIG. 3 along the line I--I of FIG. 2;
FIG. 5 is an end view of the retaining element of FIG. 3 seen in the direction of the arrow III in FIG. 3;
FIG. 6 shows a detail of the retaining element of FIG. 5 in section along the line VI--VI in FIG. 5;
FIG. 7 is a view of the screening drum connected with the closure cover of the machine seen in the direction of the arrow VII in FIG. 2 but omitting the machine housing;
FIG. 8 is a section drawn to a larger scale through the region of fastening between screening drum and closure cover seen along the line I--I in FIG. 2, but showing only the upper portion of the closure cover with the neighbouring portion of the screening drum;
FIG. 9 is a section to the same scale as FIG. 8 taken along the line I--I of FIG. 2 showing the attachment of the bar to the second ring of the screening drum, again showing only the neighbouring portion;
FIG. 10 illustrates a modification of the bar fastening arrangement on the second ring of the screening drum, corresponding to FIG. 9; and
FIG. 11 shows a view of the hexagon box spanner with slot and scale, for use in screen tensioning.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In a drum type screening machine, a shaft 2 of a centrifuging rotor 3 is mounted in a housing 1 (FIGS. 1, 2). Arms 4 which carry blades 5 are secured on the shaft 2.
The centrifuging rotor 3 is arranged within a tubular screening drum 7 which is connected securely at one of its ends by means of a tensioning device 24 to an end member in the form of a closure cover 11 and at the other end is supported on a housing ring 12 of the housing 1. The blades 5 extend into the vicinity of the screening drum 7.
The housing 1 is provided with an inlet union 13. The inlet union 13 ends at a perforated retaining element 14 which is secured on the shaft 2. The housing 1 is also provided with fines discharge hoppers 15 and 16 for the fine products that pass through. A belt pulley 18 is secured on the shaft 2 of the centrifuging rotor 3. The belt pulley 18 is driven by means of the belt 19 by an electric motor 20 whose shaft end carries a belt pulley 21.
The product to be screened, e.g. grinding stock passes through the inlet union 13, through the perforated retaining element 14, into the screening drum 7 and is conveyed in the direction towards the closure cover 11 by the blades 5 which are shaped in known manner. The retaining element 14 holds back foreign bodies and allows the product to be screened to pass through. The finer particles fall through the covering (screening cloth) 71 of the screening drum 7 and are discharged by way of the discharge hoppers 15 and 16. The large particles are conveyed into the coarse outlet hopper 111 in the closure cover 11.
The perforated retaining element 14 (FIGS. 3,4,5,6) has the task of holding back foreign bodies which could damage the covering 71 of the screening drum 7. In order to be able to carry out this task without the retained foreign bodies tumbling about in the inlet union 13 of the housing 1, the retaining element 14 is constructed as a perforated basket 141 and provided with perforations 144.
The basket 141 has a perforated plate 135 to which a perforated rim 136 is secured projecting in the direction of the inlet. It is supported by means of spokes 142 on a hub 143 and is connected securely thereto. The hub 143 itself is mounted on the shaft 2 and is secured both axially and radially on the latter. The diameter of the basket 141 is so adapted to the housing ring 12 that an annular gap 145 is formed which is smaller than the diameter of a perforation 144. Entry of foreign bodies into the screening drum 7 is thereby prevented, and the foreign bodies are held in the basket 141 securely in a stationary position by reason of centrifugal force when the machine is running.
To improve product throughflow the spokes 142 are so constructed that the lines of attachment 148 and 149 on the hub 143 and basket 141 are inclined relatively to one another, so that a conveying effect is obtained: the spokes 142 are situated at an inclination relatively to the axial direction of the centrifuging rotor 3 and act as conveying blades.
To remove the foreign bodies the basket 141 is provided with a large aperture 150 which makes it possible when the machine is stopped to reach into the basket 141 through a laterally arranged housing cover 8 (FIG. 2) and take out the foreign bodies. For this purpose the screening drum 7 with the closure cover 11 must be moved out of the machine housing.
The aperture 150 in the basket 141 is covered during operation by a movable closure element 151. The closure element is half-moon or segment-shaped. It has the same perforations 144 as the basket 141 and is connected securely to a hub constructed as a sleeve 152. The sleeve 152 itself is mounted on the shaft 2 of the centrifuging rotor to be free to turn and displaced axially. The closure element 151 is held in position by a compression spring 153 which at one end presses against the sleeve 152 and at the other end bears against the hub 143 and thus presses the closure element 151 against the edges of the aperture 150.
The closure element 151 is secured against radial turning movement by locating pins 154 which are fixed at suitable places on the basket 141 from which they project to rather more than the extent of the thickness of the closure element 151.
To remove foreign bodies with the machine stopped, pressure is applied from the outlet side against the sleeve 152 and the closure element 151 and thus the force of the compression spring 153 is overcome.
As a result the closure element 151 is displaced axially and pressed out of the region of the locating pins 154. The locating pins being cleared, the closure element 151 can be turned relatively to the basket 141 and thus frees the aperture 150. The foreign bodies can easily be removed. In order to allow the axial opening travel of the closure element 151 the spokes 142 which support the basket 141 are provided with cut outs 146. The locating pins 154 are shorter than this opening travel.
In the modification shown in FIG. 4 the function is substantially like that of the retaining element 14 shown in FIG. 3. But in this case the basket 156 is so constructed that a perforated plate 157 is at an inclination to the axis of the shaft 2 of the centrifuging rotor 3 and as a result a swash plate wobble disc effect is obtained. The rim 158 of the basket 156 is also conically shaped.
Because of the longer working life which can be expected from the covering 71 of the screening drum 7 it is necessary to arrange for this to be tightenable and loosenable i.e. for its tension to be adjustable. This is effected by a tensioning device 24 (FIGS. 7, 8, 9, 10, 11). As a support for the covering 71 (screening cloth) there is provided at the inlet side a flange ring 72 and at the outlet side a clamping ring 73 which is connected to the closure cover 11 by the tensioning device 24.
The flange ring 72 and the clamping ring 73 are spaced apart by tensioning bars 74. The covering is fixed both on the clamping ring 73 and also on the flange ring 72 by means of expander clips 75.
In the constructional form shown in FIGS. 8, 9 the bars 74 are screwed into corresponding screwthreaded holes 721 (FIG. 9) in the flange 722 of the flange ring 72, and secured with a locknut 741 i.e. connected securely and fixedly to the flange ring 72.
Near the clamping ring 73 the bars 74 are connected to the housing 1 by means of the tensioning device 24 passing through holes 112 in the closure cover 11.
In order to loosen or tighten the covering 71, the bars 74 can be displaced in an axial direction relatively to the closure cover 11 by means of the tensioning device 24. Three tensioning devices are arranged on the periphery.
At the flange portion 731 of the clamping ring 73 there are arranged screwthreaded holes 732 into which nuts 241 are screwed. The nuts 241 are screwed on the clamping ring 73 with interposition of a shim 242 until abutment is reached, and thus connected to the clamping ring 73 so as to be fast against rotation therewith.
Screwed into the nut 241 is a screwthreaded sleeve 243 having an external screwthread 231. This screwthreaded sleeve 243 is provided at the outside of the machine with a hexagonal head 244. The screwthreaded sleeve 243 also has a bore 245 which is used for receiving the bar 74. The bar 74 is secured axially relatively to the screwthreaded sleeve 243 and the extension sleeve 243+ thereof by two fixing rings 742, e.g. circlips. To seal off the interior of the machine, the screwed connection between the nut 241 and the screwthreaded sleeve 243 is protected by a felt ring sealing element 250.
The entire screening drum 7 forms one unit, with the flange ring 72 and the clamping ring 73 being spaced apart by the bars 74, and the clamping devices 24 and also the covering 71 extending between the rings 72 and 73. Tightening or loosening of the covering 71 is possible in this condition by turning the screwthreaded sleeves 243.
The nuts 241 consist of a sleeve 246 and a head 235. The head is provided with an engagement surface formed of a transverse bore 236. The sleeve 246 projects so far beyond the flange portion 731 of the clamping ring 73 that the length is sufficient to secure the closure cover 11 thereon with a lock-nut 247 and shim 248. The holes 112 are provided for this purpose on the closure cover 11 for receiving the nut sleeve 246. The sleeve 246 is provided with an external screwthread 249 which matches the locknut 247. The head 235 faces the interior of the machine.
When the screening drum 7 is screwed to the closure cover 11 the entire unit can be moved into the housing 1 and the closure cover 11 connected to the housing 1 by means of screw bolts 113. The tensioning device 24 also projects from the closure cover 11 in the assembled state and is accessible from the outside.
For uniform tightening of the covering 71 a key 26 (FIG. 11) in the form of a box spanner is provided, consisting of a hexagon tube 261 having a slot 262 at the front. A scale 263 is along the length of the slot 262. For adjustment of the covering 71, the key 26 is fitted over the hexagon head 244 until it abuts the face 264. Turning of the key 26 with a tommy bar or pin 266 inserted through a hole 267 at the end of the hexagon tube 266, screws the screwthreaded sleeve 243 in or out and thus tightens or slackens the covering 71.
The degree of tightening of the covering 71 can be read off by observing the position of the screwthreaded sleeve edge 265 in relation to the scale 263 of the key 26. Uniform adjustment of the degree of tension of the covering 71 is thus possible from the outside of the machine during operation. This construction also affords the advantage that a completely fitted-up screening drum 7 can be prepared outside the machine with the correct tension in the covering 71 without the machine having to be stopped. If the screening drum 7 is to be replaced the old drum 7 can be dismantled from the cover 11 very quickly by releasing the locknuts 247, and a new drum 7 fitted in position again in the same way. As a result shut down times during which the machine has to be inoperative are very considerably shortened.
A simpler constructional modification is also possible (FIG. 10). The bars 74 are provided at the region of the flange ring 72 with a shaped portion 743. The flange ring 72 has a number of holes 723 at the periphery corresponding to the number of bars. The bar 74 is secured axially in the flange ring 72 by means of a circlip 744. There is thus obtained a connection between bar 74 and flange ring 72 which is free in rotation but axially fast. In the region of the clamping ring (not separately illustrated) the bar 74 is provided with an external srewthread which fits directly into the screwthread 251 of the nut 241. The bar 74 projects beyond the nut sleeve 246 and is provided outside the machine with an engagement surface, e.g. a hexagonal head. By turning the bar 74 with a key 26 the covering 71 is also tightened or loosened from outside the machine.
To reduce the free vibration length of the covering 71 elastic buffer elements 745 (FIG. 7) can be provided on the bars 74. Internally of the covering 71 a support hoop 76 is mounted, corresponding axially to the position of the buffer element 745, and secured with the expander clip 75. The diameter of the buffer element 745 can be so chosen that it abuts on the expander clip 75, or an air gap 77 is formed between the buffer element 745 and the expander clip 75. With this apparatus and with suitable choice of the number of buffer elements 745 and support hoops 76, distributed along the length of the covering 71, the pulsation of the covering 71 can be influenced to suit the particular product and the length of the machine. | A drum type screening machine has a centrifuging rotor within it. A perforated retaining element is carried by the shaft between a feed inlet and an entry region of the drum. Use of the retaining element prolongs the screen life so much that tension adjustment become necessary. Provision is made for this to be done from outside of the machine. The screening drum has a pair of rings which support the screening cloth and which are held apart at an adjustable distance by tensioning bars. One ring is supported within an end member of the machine housing and the other on support means within the housing. Each bar is externally threaded, e.g. by way of an extension sleeve that is axially fast with the bar. The sleeve is engaged by an internally threaded nut which is axially fast with the end member of the machine. The sleeve extends through that nut and through the end member to the outside of the machine. A hexagonal head formed on the end of the sleeve can be turned exteriorly of the machine with a box spanner, thereby to tension the screen cloth. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to automobile ignition systems, and particularly, to apparatus which is compatible with a standard distributor assembly for the replacement of the condenser and the points, and optionally the distributor cap.
2. Description of the Prior Art
The standard automobile distributor typically comprises a stator in the form of a cast housing, a support member, such as a plate, within the housing for carrying such elements as the breaker points, condenser and wiper, a rotor shaft which extends through the housing and through the support plate and a rotor assembly which is carried by the shaft. The breaker points which are mounted within the housing comprise a spring-biased arm carrying one of two metal electrodes which contact each other when an octagonal cam on the distributor shaft rotates past and in contact with the arm. In this manner, ignition timing pulses are generated in proportion to the engine speed.
Such prior art systems have been in existence and functioned properly until a tune-up was needed for years. It is well-known that, when tuning an engine, it is standard practice to replace the spark plugs, the points and the condenser -- the latter two items being of interest here. The replacement is due to the deterioration that takes place from constant usage. The deterioration has an effect not only on gas mileage, a very important matter these days, but also on engine performance.
In the past, it was quite difficult for the do-it-yourself vehicle owner to give his car a tune-up without making a capital investment in a timing light and a dwell meter. These items were considered necessary for setting the proper timing. Also, the setting of the proper gap width, in thousandths of an inch, requires a great deal of skill.
In order to negate the requirement of capital investment, and a great deal of skill and patience, the instant invention has been developed to allow the vehicle owner to quickly and easily replace the condenser and points of his engine and re-install the same with absolute accuracy.
SUMMARY OF THE INVENTION
It is an object of this invention to provide a low-cost, simple to install, pre-packaged points and condenser system to replace the original equipment or previously replaced points and condenser.
In general, the invention comprises a cartridge of generally cylindrical shape, of metal or plastic or a combination thereof, with a top horizontal plate and a bottom horizontal plate, parallel to each other and at right angles to an upstanding wall of the cartridge. Two apertures, one per plate, are provided in vertical alignment. A vertical shaft is positioned in the plate apertures, and is held in place by a support bearing positioned on the inward facing side of the top plate. Suitably positioned, as is known to the art, is an octagonally shaped cam on the shaft. This cam operates to open and close the mechanical breaker points to be described below. Mounted in a spaced parallel arrangement to the bottom plate is a weight plate. The weight plate contains a slotted aperture in vertical alignment with a similar aperture in the bottom plate. Partially secured and spaced from the weight plate is a contact plate. The breaker points and condenser are secured in a rigid manner to the contact plate. A replacement rotor cap or the previously used one is mounted on the shaft of the cartridge in conventional manner. The lower portion of the shaft of the cartridge is adapted to mount on the top portion of the existing distributor shaft by engagement. An activating pin positioned vertically from the contact breaker plate extends vertically through the aligned slotted apertures. This pin engages the vacuum advance plate of the housing and from which the original equipment points and condenser are removed, whereby the vacuum advance can operate in conventional manner. Mounted on the breaker plate are the condenser, and a pair of pre-set breaker points which ride against the vertical center shaft cam in a manner duplicating their operation in prior art apparatuses. The breaker plate is configured to match the original equipment vacuumm advance plate, at least in operation, if not in shape. The breaker points and condenser are of conventional design and need not be discussed further.
The distributor cap is placed in superposed axial alignment on the top portion of the cartridge, such that the top plate projects into the distributor cap housing, the top plate having an outside diameter substantially equal to the inside diameter of the lip portion of the cap. In another embodiment, the distributor cap forms an integral piece with the side wall of the cartridge, thus eliminating the necessity of the top plate. This would also do away with the conventionally used locking spring clips which are used to secure, in a removeable fashion, the cap to the cartridge.
It is an object, therefore, to provide a replaceable tune-up cartridge with factory pre-set points.
It is another object to provide a means of installing a set of points without a large capital investment for special lights, meters and gapping tools.
It is a further object of this invention to provide a means for the average consumer to replace his points and condenser with no prior training.
In order that the invention in all its aspects may be fully understood, reference is made to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of an electrical distributor assembly embodying the instant invention;
FIG. 2 is a top plan view of the cartridge of the instant invention with the shaft, condenser and points shown in dotted lines;
FIG. 3 is a top plan view of the cartridge of FIG. 2 with, the contact terminals of distributor cap vertical, shown in operative position;
FIG. 4 is a vertical, side view of the cartridge of FIG. 2, and FIG. 5 is a vertical, side view of the cartridge of FIG. 2 with the distributor cap positioned thereon.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, there is shown a distributor assembly 11 for an automotive ignition system and comprising a housing 21 and a shaft assembly 22 which is rotatable relative to the housing 21 about a longitudinal vertical axis. Horizontally positioned and affixed to the housing 21 is a conventional vacuum advance assembly 13.
At the upper or inner end of the rotor shaft assembly 22, a portion of reduced diameter, namely 14, extends through the housing 21 and rotates with an octagonal cam 33 (see FIG. 4), which operates to open and close the mechanical breaker points (shown in dotted lines in FIG. 2) in a standard distributor assembly, but which in this invention engages collar 15, to form an extended shaft assembly particularly to operate the breakerpoints present in cartridge 2, as seen particularly in FIG. 2, and the rotor 7 mounted therein (see also FIGS. 2 and 4).
Cartridge 2 comprises a cylindrical housing having an upstanding wall 20, abottom annulus-shaped plate 18 with the annular bore 18' having collar 15 suspended therein and held in place by bearings or other retaining means, not shown, the collar 15 being in longitudinal alignment to engage shaft section 14.
Aperture 5' is suitably positioned on the bottom plate 18 such that a vacuum activating pin 5 is adapted to engage the vacuum advance mechanism 13 in conventional manner. Pin 5 is a partially threaded screw which connects points assembly 8 (see also FIG. 2) to breaker plate 28 (FIG. 4) and which protrudes through a pair of aligned apertures to engage vacuum advance assembly 13 as is known in the art.
Suitably positioned, preferably 180° apart, are flanges 16, configured to engage retaining clips 12 whereby the cartridge 2 is held position in superposed relationship to the housing 21. In the preferred embodiment plate 18 is recessed slightly into wall 20, and the diameter ofwall 20 is set slightly larger than the inner diameter of the upper housing22a of housing 21 of the shaft assembly 22, such that upon engagement of one with the other, the inner wall of wall 20 will overlap and be in contact with a circular portion of the top of the housing 21, portion 22a.
Emerging from an opening in the upstanding side wall are a pair of wires 3 and 4, which may be color-coded, such as one black and one white, preferably with connectors 23, 24 thereupon at the protruding ends. The connectors 23, and 24, respectively, may be used to connect the points to the coil and the cartridge 2 to ground, as is well known.
Suitably positioned on the cartridge 2, usually in vertical alignment with flanges 16 and 16a, are spring clips 10 and 10a. These are mounted in any conventional manner, and are adapted for engagement with flanges 25 and 25a of a conventional distributor cap 1.
Top plate 26 (FIG. 2) may be positioned to have its under surface abut the upper peripheral edge of wall 20, or the plate 26 may be recessed into theinterior of wall 20, or it may protrude beyond the upper peripheral edge ofwall 20, when the plate 26 is positioned in register with the wall 20.
Rotor arm 7 (see also FIG. 2) generally may be positioned in only one mode upon the upper end of assembly 15, which shaft assembly 15 protrudes through an aperture 26' (see FIG. 4) in the center of plate 26, in alignment with the central aperture 18' of plate 18. Rotor arm 7 is provided with a resilient contact 17 (FIGS. 2 and 4) which contacts a spaced contact terminal 15', shown in FIG. 3, wherein they are seen to eight in number and positioned on the interior of the cap 1. The cap 1 maybe mounted on the body of the distributor assembly 11 in register therewith, and retained in position by means of the spring clips 10 and 10a engaging flanges 25, 25a, respectively. A set of points 8 and a condenser 9 are mounted on the top surface of plate 19, as shown in FIG. 2.
In an alternative embodiment, posts 25 and 25a, and clips 10 and 10a may beomitted and the cap may be pre-attached to the cartridge 2 at the factory, as by adhesion using a suitable cement, after the remainder of the cartridge is assembled. This embodiment is not shown since it would be identical to FIG. 5 save for the elimination of posts 25, 25a and clips 10, 10a.
As discussed, the vacuum advance plate assembly 13 includes a plate recessed into housing 21 which is engaged by pin 5 for operation thereof, which is well-known in the art. This forms no part of the invention and further description is deemed unnecessary.
FIG. 4 shows the wires 3 and 4 with connectors 23 and 24 thereon, respectively. Bottom plate 18 is shown to be recessed into and secured to side wall 20, such as by the use of an adhesive. Fixedly secured to the bottom plate, which need not be recessed as discussed, is the weight plate27. This is secured by a plurality of screws and associated nuts, all denoted as 30, and is spaced apart therefrom.
Contact breaker plate 28 is pivotally connected to weight plate 27, and spaced therefrom by a plurality of spacer members, with which it is in contact with, and in a horizontal plane to the weight plate 27. Again, these parts are conventional and need not be discussed further.
One of the connecting screws, 30, may be utilized as a ground-lug, and is seen to be the attachment point for fround wire 4, as well as for a groundconnection between the breaker plate 28 and the weight plate 27.
Mounted on the breaker plate 28 is a breaker point assembly 8, and a condenser and condenser holder 9 (see also FIG. 2).
Top plate 26, as heretofore discussed, is positioned at substantially rightangle to the upstanding side wall 20, and spaced apart from contact with any other component of cartridge 2. The top plate 26 contains a central bore 26' and an optional aperture 26" (see FIG. 2) in vertical alignment with the screw utilized to adjust the breaker points of assembly 8.
Rotor shaft or collar 15 is of conventional design and secured to the top plate 26 by a mounting bearing 32. The shaft or collar 15 protrudes through the central bore 26' and is positioned at right angles to the top plate 26. The amount of protrusion is sufficient only to allow the rotor 7to be mounted thereon in close proximity to the top plate 26. This shaft orcollar 15 extends the length of the inside of the cartridge 2 and has the octagonally shaped cam 33 mounted thereon, as in a conventional distributor arrangement, the cam 33 being positioned vertically between the bearing 32 and the breaker plate 28. Shaft or collar 15 may be comprised of interconnected sections as is well known in the art.
Shaft or collar 15 thus includes a slotted lower end forminng a slotted coupling on the underside of cam 33, as shown in FIG. 1. As indicated previously, the slotted coupling engages distributor shaft 14 to provide arotative motion to rotor 7. Needless to say, the nature of the connection between 14 and 15 may be altered so long as the desired result is achieved.
Wire 3, shown to be exiting through a grommet 3' in FIG. 4, is the connector from the condenser 9.
While the top and bottom plates are disclosed to be adhesively connected, it may be readily seen that any securing arrangement is contemplated to beused in conjunction with an adhesive or in replacement thereof, so long as the proper spatial relationship is maintained.
The upstanding side wall 20 and the top and bottom plates 26 and 18 of the cartridge 2 may be all made of either plastic or metal or a combination thereof. Optionally, a rubber or other suitable sealing strip (not shown) may be provided on the housing 21 or the cartridge 2 at their surface interface and at the interface of the distributor 1 with the cartridge 2 to impede the ingress of moisture and dirt.
All of the components utilized in the cartride 2 are specifically chosen tobe compatible with the original factory equipment of the particular brand of car, by year and model number, where the cartridge 2 is to be employed.Thus the specification of, for example, the condenser 9, would match the specifications of the condenser 9 that is being replaced.
In the same vein, the breaker points that are installed in the cartridge 2 are intended to be pre-set at the factory to match the factory specifications, including the proper gap.
The breaker points and condenser may be placed beneath the top plate 26 where they are free from access by the consumer. Thus the integrity of thegap setting done by the factory is preserved. Continuing in this vein, it is seen that a prescored line may be circumscribed on the top plate 26, such that on removal of the circumscribed area, an aperture is formed, andthat an aperture is formed when the pre-scoring is fully scored. Through this aperture, which should be positioned for direct access to the breakerpoints, and which will vary for make and model car, proper tools may be utilized to maximize or fine tune the gap. This pre-scored portion is shownin FIG. 2 and thus opening 26" may be eliminated, if desired. Thus, the points and condenser may be mounted as shown in FIG. 4 or directly onto the underside of top plate 26. Since such a view would be identical to that of FIG. 2, no further illustration is deemed necessary.
Thus, there is provided a tune-up cartridge for a spark ignition internal combustion engine, which engine may be fitted with replacement contact points in a minimum of time and with none of the trouble and inconvenienceinvolved with which one may be familiar in such replacement under prior artconditions. Thus the necessity of a feeler gauge is eliminated. One will not lose the small screws necessary to re-install new breaker points, as often happens.
Additionally, in one preferred embodiment, the possibility of moisture reaching the rotor contact points is eliminated, when such is preassembledor pre-moulded to the cartridge.
It is also seen that in one embodiment, that moisture is prevented from entering the points area, causing malfunction of the car's operation.
In tests on a late model U.S. car, it was found that the tuneup time attributable to changing the points and condenser was lowered from the normal 45 to 60 minutes, to about 10 minutes; and, that no tools other than those in the average homeowner's garage were needed to accomplish thejob.
It is seen that there can be an optional circular lip 40 whose outside dimensional radius is equal to the inside radius of the upstanding side wall 20. This lip's wall thickness abuts the top plate 26, and serves to prevent lateral movement of the cap 1, when such is placed into position, as a separate non-integrated unit.
It is seen in retrospect that the tuneup cartridge of this invention can have its shaft's lower portion engage the top portion of the present distributor shaft by any known means of engagement. Thus the cartridge caneither internally or externally engage the distributor shaft. Therefore thecartridge may be inserted into the keyway of the distributor shaft. While not necessarily recommended, it is also to be seen that an intervening keying mechanism, perhaps with a plurality of splines could be interposed between the two shafts, so afford the desired connection.
While the embodiments discussed above all relate to the use of but one set of points and one condenser, it is to be seen that tuneup cartridges bearing a plurality of points and/or condensers can be prepared and are within the scope of this invention. Such dual systems are considered advantages toward the attainment of a high performance spark.
Since certain changes may be made in the above apparatus without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. | In a distributor assembly having a conventional cap with terminals therein and a conventional rotor assembly having a rotor shaft and vacuum advance mechanism, the improvement comprising a cartridge assembly housing disposed between the cap and the rotor assembly having a vacuum actuating pin engaging the vacuum advance mechanism and a connecting shaft inter-connecting the cap and the rotor shaft. The housing includes a conventional breaker point assembly, condenser and actuating cam therein and appropriate electrical connections. The cartridge assembly includes access therein for adjusting the point assembly and may be either permanently secured to the distributor cap or separable therefrom. In this manner, a vehicle owner can quickly and easily replace points and condenser in his vehicle without complicated equipment. | 5 |
BACKGROUND
[0001] 1. Field of Invention
[0002] The invention relates generally to the field of oil and gas production. More specifically, the present invention relates to a system and method for stacking perforating guns to form a perforating string.
[0003] 2. Description of Prior Art
[0004] Perforating systems are used for the purpose, among others, of making hydraulic communication passages, called perforations, in wellbores drilled through earth formations so that predetermined zones of the earth formations can be hydraulically connected to the wellbore. Perforations are needed because wellbores are typically completed by coaxially inserting a pipe or casing into the wellbore. The casing is retained in the wellbore by pumping cement into the annular space between the wellbore and the casing. The cemented casing is provided in the wellbore for the specific purpose of hydraulically isolating from each other the various earth formations penetrated by the wellbore.
[0005] Perforating systems typically comprise one or more perforating guns strung together, these strings of guns can sometimes surpass a thousand feet of perforating length. In FIG. 1 a prior art perforating system 11 is shown having a perforating gun string 4 with perforating guns 6 . The gun string 4 is shown disposed within a wellbore 1 on a wireline 5 . The perforating guns 6 in the gun string 4 are usually coupled together by connector subs 13 . A service truck 7 on the surface 9 generally accompanies perforating systems 11 for handling the upper end of the wireline 5 . The wireline 5 typically is used for raising and lowering the gun string 4 , as well as a communication means and control signal path between the truck 7 and the perforating gun 6 . The wireline 5 is generally threaded through pulleys 3 supported above the wellbore 1 . As is known, derricks, slips and other similar systems may be used in lieu of a surface truck for inserting and retrieving the perforating system into and from a wellbore. Moreover, perforating systems are also disposed into a wellbore via tubing, drill pipe, slick line, and/or coiled tubing.
[0006] Included with the perforating gun 6 are shaped charges 8 that typically include a housing, a liner, and a quantity of high explosive inserted between the liner and the housing. When the high explosive is detonated, the force of the detonation collapses the liner and ejects it from one end of the charge 8 at very high velocity in a pattern called a “jet” 12 . The jet 12 perforates the casing and the cement and creates a perforation 10 that extends into the surrounding formation 2 .
[0007] Typically the gun string 4 is inserted within a lubricator that is then mounted on a wellhead assembly for deployment into a wellbore. The lubricator provides a pressure seal around the string 4 so the gun string 4 can be pressure equalized with the usually higher pressure wellbore prior to being deployed therein. In some instances space constraints at the well site may limit the height of the lubricator thereby in turn limiting the length of the gun string 4 .
SUMMARY OF INVENTION
[0008] Disclosed herein is an example method and apparatus for perforating a wellbore. In one example method a string of perforating guns is formed by inserting a perforating gun into a wellbore and then anchoring the perforating gun to a wall of the wellbore. Another perforating gun is then inserted into the wellbore and lowered onto the anchored perforated gun. These guns are then coupling to one another to form a string of perforating guns. Alternatively, the anchor on the perforating gun is removed and the string is lowered deeper into the wellbore. Optionally, a plurality of perforating guns is added into the wellbore that are coupled to each adjacent perforating gun. In an example embodiment, each perforating gun is lowered via wireline into the wellbore. Optionally, wet connections are provided on each of the perforating guns, so that when the perforating guns are disposed in liquid and coupled to one another, the perforating guns are in electrical communication through the wet connectors. Optionally, an anchor can be added onto the perforating gun, so that by deploying the anchor from the perforating gun into contact with the wall of the wellbore the perforating gun is anchored in the wellbore. Further, the method can include resetting the anchor, decoupling the another perforating gun from the perforating gun, and removing the another perforating gun and the perforating gun from the wellbore.
[0009] An alternate method of perforating a wellbore is provided herein that includes anchoring a perforating gun to a wall of the wellbore and coupling another perforating gun to the perforating gun anchored to the wellbore wall to form a perforating gun string. The perforating gun is released from the wall of the wellbore and the perforating string is lowered to a designated depth within the wellbore where the wellbore is perforated by detonating shaped charges disposed within the perforating string. Communication may occur between the perforating gun and the another perforating gun. As the shaped charges in either of the perforating gun or the another perforating gun may be detonated at different times, the method may further include moving the perforating string to a depth different from the designated depth of the initial step of detonation, and detonating shaped charges not already detonated. Optionally, a plurality of additional perforating guns may be provided, where the additional perforating guns are coupled to the upper end of the another perforating gun. The perforating string can be re-anchored in the wellbore, and each of the guns selectively decoupled. A connector for connecting each adjacent gun may optionally be provided, wherein each connector is assigned an address, so that by directing a signal to the address each of the guns are selectively decoupled.
[0010] Also described herein is a perforating system, that in one embodiment is made up of a lower perforating gun, a selectively deployable anchoring device on the lower perforating gun, an upper connector on an upper end of the lower perforating gun, and a contact on an end of the upper connector distal from the lower perforating gun. The contact is in signal communication with the lower perforating gun. Also included is an upper perforating gun with a lower connector on its lower end, where the lower connector automatically connects to the upper connector when the lower connector lands on the upper connector. In an example embodiment, a receptacle is on an end of the lower connector distal from the upper perforating gun. An opening in the receptacle is in signal communication with the upper perforating gun, so that when the upper and lower perforating guns are coupled the upper and lower connector are mated such that the contact inserts into the opening and the upper and lower perforating guns are in signal communication. In an example embodiment, a selectively releasable coupling is provided that is disposed in at least one of the lower connector or lower connector. In an example embodiment, a communications module is provided in the upper perforating gun in signal communication with a communications module in the lower perforating gun. In an example embodiment, signal communication between the communications modules in the upper and lower perforating guns is routed through the connectors.
BRIEF DESCRIPTION OF DRAWINGS
[0011] Some of the features and benefits of the present invention having been stated, others will become apparent as the description proceeds when taken in conjunction with the accompanying drawings, in which:
[0012] FIG. 1 is a side partial sectional view of a prior art perforating system used for perforating a wellbore.
[0013] FIGS. 2A through 2C are side partial sectional views of a perforating string being stacked together in a wellbore in accordance with the present invention.
[0014] FIG. 3 is a perspective side sectional view of an example embodiment of a connector for perforating guns in accordance with the present invention.
[0015] FIG. 4 is a side partial sectional view of a method of perforating a wellbore in accordance with the present invention.
[0016] FIGS. 5 through 7 are perspective side sectional views of alternate example embodiments of connectors for perforating guns in accordance with the present invention.
[0017] FIG. 8 is a side partial sectional view of an example of removing a perforating string from a wellbore in accordance with the present invention.
[0018] While the invention will be described in connection with the preferred embodiments, it will be understood that it is not intended to limit the invention to that embodiment. On the contrary, it is intended to cover all alternatives, modifications, and equivalents, as may be included within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF INVENTION
[0019] The method and system of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings in which embodiments are shown. The method and system of the present disclosure may be in many different forms and should not be construed as limited to the illustrated embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey its scope to those skilled in the art. Like numbers refer to like elements throughout.
[0020] It is to be further understood that the scope of the present disclosure is not limited to the exact details of construction, operation, exact materials, or embodiments shown and described, as modifications and equivalents will be apparent to one skilled in the art. In the drawings and specification, there have been disclosed illustrative embodiments and, although specific terms are employed, they are used in a generic and descriptive sense only and not for the purpose of limitation. Accordingly, the improvements herein described are therefore to be limited only by the scope of the appended claims.
[0021] FIGS. 2A through 2C illustrate an example method of forming a perforating gun string within a wellbore. More specifically and with reference to FIG. 2A , a perforating gun 20 1 is shown being lowered into a wellbore 22 by attachment on its upper end to a cablehead 24 . A wireline 26 mounts on a side of the cablehead 24 opposite a side where it couples to the upper end of the perforating gun 20 1 . The wireline 26 , which inserts into the wellbore 22 through a wellhead assembly 28 , may be spooled from a service truck (not shown), derrick (not shown), or other deployment means disposed on the surface. Shaped charges 30 are provided with the perforating gun 20 1 and shown positioned to direct a jet radially outward from the perforating 20 1 . Also included with the perforating gun 20 1 of FIG. 2A is an anchor 22 in a retracted mode and circumscribing the outer surface of the perforating gun 20 1 . In the example embodiment of FIG. 2B , the anchor 32 A is deployed and extends across the annulus between the perforating gun 20 1 and an inner wall of the wellbore 22 . The anchor 32 A exerts opposing forces against the perforating gun 20 1 in the wall of the wellbore 22 thereby suspending the perforating gun 20 1 at a designated location within the wellbore 22 . Once supported within the wellbore 22 by the anchor 32 A, the cablehead 24 can be released from the perforating gun 20 1 and drawn up the wellbore 22 for optional attachment of a subsequent perforating gun 20 2 ( FIG. 2C ) and lowered on the wireline 26 and onto the anchored perforating gun 20 1 . This process is repeated until a string of perforating guns is formed. When a string of designated or desired length is formed, the anchor 32 A can be released thereby allowing the string to be deployed to a depth or depths for perforating operations.
[0022] Attachment between perforating guns may occur upon landing a perforating gun on an adjacent lower perforating gun. Shown in a perspective and side section view in FIG. 3 is one example of a connector 33 for coupling adjacent guns. In the example of FIG. 3 , the connector 33 includes an upper connector 34 and lower connector 36 . The lower connector 34 of FIG. 3 is a generally annular member shown having a set of slips 38 whose outer radius increases with distance away from the upper end of the upper connector 34 . The slips 38 mount on a mandrel 40 , that as will be described in more detail below, is selectively movable in an axial direction within the upper connector 34 . Collet like ribs 41 are provided on a lower end of the lower connector 36 that in the example of FIG. 3 are raised profiles shown circumscribing the outer surface of the lower end of the lower connector 36 . In one example embodiment, the upper connector 34 mounts on an upper end of a lower positioned perforating gun, and the lower connector 36 mounts on a lower end of an upper positioned perforating gun. Such that when the upper perforating gun lands on the lower gun, the surface of the lower connector 36 having the ribs 41 inserts into the upper end of the upper connector 34 and into the annular space between the slips 38 and inner surface of the upper connector 34 . The contour of the slips 38 outwardly urges the ribs 41 into engaging contact with the inner wall of the connector 34 as the lower connecter 36 inserts into the upper connector 34 ; thereby coupling the adjacent perforating guns attached on opposing ends of the connector 33 . By axially moving the mandrel 40 in a direction downward, i.e. away from the lower connector 36 , the slips 38 move away from the ribs 41 thereby allowing the upper and lower connectors 34 , 36 to be disengaged.
[0023] FIG. 4 provides in a side partial sectional view one schematic example of perforating within the wellbore 22 . A perforating string 42 is shown made up of perforating guns 20 1 , 20 2 , . . . 20 n and connectors 33 for coupling each of the adjacent perforating guns. The perforating string 42 may be constructed by landing the guns 20 1 , 20 2 , . . . 20 n sequentially in series top to bottom. Attachment between adjacent guns is not limited to the connector of FIG. 3 , but can include any type of connection that provides for latching upon landing that may be later selectively released. Components of the gun string 42 are shown in communication via a communication link 44 . The communication link 44 includes a main bus 46 from which individual lead buses 48 , 50 , 52 , 54 communicate directly with one of the perforating guns as well as the cablehead 24 . Modules provided in each of the perforating guns 20 1 , 20 2 , . . . 20 n are equipped with communication devices enabling communication with any of the other guns, the cablehead 24 , or the surface via the wireline 26 . Moreover, communication may occur through hard links, such as wires that extend along the length of the perforating string 42 as well as wireless links that extend along the wellbore 22 . Examples of wireless communication include radio waves, mud pulses, acoustic signals and the like. Further illustrated in the example of FIG. 4 is that the shaped charges 30 within perforating gun 20 1 are being detonated to form jets 56 that project radially outward from the perforating string 42 and form perforations 58 into the formation 60 surrounding the wellbore 22 . The control modules within the perforating guns enables selective detonation within a single gun and so that a subsequent detonation of a different one or more of the guns in the perforating string 42 can occur while at the same position within the wellbore 22 , or at a different depth and at a later time.
[0024] Schematically presented in a side view in FIG. 5 is an alternate example of a connector 33 A used to connect adjacent perforating guns 20 i , 20 i+1 . An upper connector 34 A is shown that includes a firing head 62 that can be used to control detonation of shape charges within the connected perforating gun 20 i . In the example of FIG. 5 , an initiator 64 is shown for initiating a detonation wave within the perforating cord 65 for detonating charges 30 within the perforating gun 20 i . Also illustratively shown within the firing head 62 is a transmitter/receiver 66 that is used for receiving signals within the firing head 62 for controlling operation of the associated perforating gun 20 i . The signals may be provided to the transmitter receiver 66 via hardwire (not shown) or wireless signals as discussed above. The use of the term signals herein includes discrete and analog signals that represent or contain information, such as data or commands, as well as an electrical flow of power. A controller 68 is further optionally provided within the firing head 62 for processing signals received from the transmitter receiver 66 and controlling operation of the initiator 64 as well as controlling operation of any data signals that may be transmitted from the transmitter receiver 66 . In an optional embodiment, a latching actuator 70 is shown within the lower connector 36 A for automating actuation, release, or both of an actuating mechanism (not shown) for coupling together the upper and lower connectors 34 A, 36 A of the connector 33 A. Alternatively, the latching actuator 70 may be provided within the upper connector 34 A as well as the lower connector 36 A, or instead of being within the lower connector 36 A.
[0025] FIGS. 6 and 7 provide in perspective view examples of alternate connectors 33 B, 33 C and that may be useful for a wet connect. For the purposes of discussion herein, a wet connect is a connection formed submerged or in the presence of a fluid, such as wellbore fluid, and when formed provides a pathway for signal travel therethrough. The connector 33 B embodiment of FIG. 6 includes a lower connector 34 B in which connector pins 72 , 74 are provided on an upper end shown projecting towards a lower end of the lower connector 36 B. The connector pins 72 , 74 , which may be formed from a conductive material, are in signal communication with leads 76 , 78 shown depending within the upper connector 34 B. Examples of the leads 76 , 78 include wire, cable, as well as fiber optic material. Receptacles 80 , 82 are shown fitted within the lower end of the lower connector 36 B and have openings therein shown facing in the direction of the pins 72 , 74 . Leads 84 , 86 are shown provided in the lower connector 36 B that connect to and are in electrical and signal communication with the receptacles 80 , 82 . As such, by inserting the pins 72 , 74 into the openings within the receptacles 80 , 82 a line of electrical and/or signal communication is created from leads 84 , 86 through leads 76 , 78 . Alignment of the receptacles 80 , 82 with the pins 72 , 74 may be accomplished via a post 88 shown protruding from an outer surface of the lower connector 36 B and a profile 90 that is formed along the inner surface of the upper end of the upper connector 34 B. In one example the post 88 lands on the profile 90 and as the lower connector 36 is urged further downward, the post 88 slides to a low point within the profile 90 thereby rotating the lower connector 36 B to align the pins 72 , 74 with the receptacles 80 , 82 for ready insertion therein.
[0026] In the embodiment of FIG. 7 , the connector 33 C includes upper and lower connectors 34 C, 36 C wherein the upper connector 34 C has a single connector pin 92 . Contacts 94 , 96 are shown provided on the outer circumference of the connector pin 92 that are separated from one another at distinct spaced apart axial locations. The leads 76 , 78 connect respectively with the contacts 94 , 96 so that electrical and signal communication exists between the contacts, 94 , 96 and leads 76 , 78 . Similarly, a single receptacle 97 is shown set within the lower end of the lower connector 36 C and having an opening facing the connector pin 92 ; thereby when the upper and lower connectors 34 C, 36 C are substantially coaxially aligned, the connector pin 92 is readily inserted into the receptacle 97 . Corresponding contacts 98 , 100 are provided within the inner surface of the receptacle 97 that engage the contacts 94 , 96 when the pin 92 inserts into the receptacle 97 , so that electrical and signal communication extends from the leads 76 , 78 and to the leads 84 , 86 shown connected to the contacts 98 , 100 .
[0027] As discussed above the perforating string 42 may be dismantled in a manner similar to its construction illustrated in FIGS. 2A through 2C . In an example embodiment of dismantling provided in side partial sectional view in FIG. 8 , the string 42 is shown deployed on wireline 26 at a depth relatively proximate to the wellhead housing 28 with the anchor 32 A deployed thereby supporting the string 42 within the wellbore 22 . The signaling sequence of FIG. 4 may be utilized, i.e. through lines extending through the perforating string 42 or wireless signals, to address each of the connectors 33 within the string 42 . Providing a specific address to each of the guns or each specific connector 33 enables selective delatching of the individual perforating guns for retrieval from within the wellbore 22 . Stacking and destacking the string 42 proximate the wellhead housing 28 allows for a perforating gun string to have a sufficient number of guns so that wellbore perforating can be accomplished with a single trip into a wellbore; which significantly reduces the time required for multiple trips in and out of a wellbore with shorter gun strings.
[0028] The present invention described herein, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned, as well as others inherent therein. While a presently preferred embodiment of the invention has been given for purposes of disclosure, numerous changes exist in the details of procedures for accomplishing the desired results. These and other similar modifications will readily suggest themselves to those skilled in the art, and are intended to be encompassed within the spirit of the present invention disclosed herein and the scope of the appended claims. | A system and method of perforating by stacking a perforating string within a wellbore, then deploying the perforating string to a designated depth for detonating shaped charges in the perforating string. The string can be formed by anchoring a single perforating gun in the wellbore, then landing subsequent guns on one another atop the anchored gun. Wet connects on the ends of the perforating guns enable mechanical engagement of each adjacent gun as well as signal communication through the connections. | 4 |
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 13/385,835, filed Mar. 9, 2012, now pending.
FIELD AND BACKGROUND OF THE INVENTION
[0002] This application relates to relief of discomfort arising from congestion whether due to infection, allergic response or simple mechanical irritation. While the use of hypertonic solutions to relieve nasopharyngeal congestion has been known, the usual concentration on the market contains approximately 3% sodium chloride. Saline solutions containing sodium chloride/water commonly on the market are 0.65%, 0.9%, and 3% sodium chloride. However, it has now been found that the range at which hypertonic saline will provide most effective response without a rebound congestion is quite narrow, being from 2.3% to and including 2.7% w/v sodium chloride/water, with the most preferred concentration being 2.4% to and including 2.6% w/v of sodium chloride in water. The method of the invention does not require use of a nasal cup or other complicated equipment. Applications by mist, drops or as a flowing liquid over the membranes are all effective.
[0003] Pain and discomfort are experienced when the mucous membrane swells as it becomes inflamed, blocking the drainage of fluid from the sinuses into the nose and throat. Mucus and fluid build up inside the sinuses, causing pressure and pain. The discomfort and problems related to some prior treatments are further complicated because bacteria are more likely to grow in sinuses that are unable to drain properly. Bacterial infection then further increases inflammation and pain. Similarly, the eyes may also be damaged by exposure to contaminants or infection which cause irritation or permanent damage to the eye.
[0004] U.S. Pat. No. 6,645,532 to Lutin teaches use of hypertonic saline for preventing discomfort in the ears using hypertonic solution in a most preferred range of 2.4% to and included 2.6% w/v sodium chloride/water. The method of that patent requires that the individual retain the solution for at least 5 seconds, then expel the saline under pressure to avoid or remedy discomfort arising from obstruction/congestion in the Eustachian tubes. The instant invention for relief of nasal congestion does not require expelling the saline under pressure, since there is no need to open the Eustachian tubes for relief of simple nasal congestion.
[0005] U.S. Pat. No. 6,899,903 to Quillin teaches a composition for cleansing the sinuses using a solution containing Baptisia tincturia colloidal silver, grapefruit seed extract and oregano juice and, further, incorporating 0.01% to 5% sodium chloride. The lone example uses a solution containing 0.75% sodium chloride. However, as indicated below, some of these concentrations of sodium chloride in water are ineffective and some cause undue irritation. The lower concentrations of sodium chloride tested as disclosed herein were essentially ineffective for purposes of relieving congestion, and, in fact, the studies showed that the lower concentrations of sodium chloride hydrate the tissue, increasing congestion.
[0006] U.S. Pat. No. 6,258,372 to Jones teaches use of a solution containing xylitol/xylose and between 0.45% and 0.95% sodium chloride with a preferred concentration of 0.65% sodium chloride, a concentration which is far less effective for relieving congestion than the preferred concentration disclosed and claimed herein. (The Jones reference teaches preferred concentrations of sodium chloride which are hypotonic,)
[0007] U.S. Pat. No. 5,897,872 to Picciano teaches a nasal moisturizing saline solution containing iodine and hypotonic 0.65% sodium chloride.
[0008] Rabago, et al., “Efficacy of Daily Hypertonic Saline Nasal Irrigation Among Patients with Sinusitis: A Randomized Controlled Trial”, Journal of Family Practice, December 2002, Vol. 51, No. 12: 1049-1055 teaches use of 2% hypertonic saline as a nasal irrigation for treatment of sinusitis. The method of Rabago, et al. involves use of a nasal cup. That concentration of sodium chloride has been shown to be less useful in the testing as shown below when using the much simpler methods of the invention.
SUMMARY OF THE INVENTION
[0009] It is the purpose of this invention to relieve discomfort arising from congestion of the mucous membranes of the nasal passages or irritation of the eye. While there are many references which teach use of saline to relieve congestion, it has now been found that a very narrow range of salt concentration provides optimal relief without discomfort. Hypertonic saline of 2.3% to and including 2.7% (preferably 2.4% to and including 2.6%) gives optimum results without causing irritation or with minimal irritation. When lower levels of salinity than taught herein are used, the treatment is less effective. When washes with higher salinity are used, there is often irritation to the membranes and the initial effect may be countered with a rebound swelling. The methods and equipment used may vary. However, any means which delivers the saline to the membranes is acceptable.
DETAILED DESCRIPTION OF THE INVENTION
[0010] As indicated in the Background of the Invention, many references teach a wide range of salt concentrations of saline without any suggestion that the concentration used as described herein would have any improved benefit. Moreover, none of the references teach the simple application of saline within the range taught herein as a means of providing relief from congestion of the mucous membranes. Unlike the method taught in U.S. Pat. No. 6,645,532 to Lutin for relief from discomfort in the ears, there is no need for the patient suffering from simple congestion of the mucous membranes to exert pressure by blocking the nose when expelling the saline. In fact, mere washing of the membranes with the saline provides relief and is preferred. The saline may be administered in any way that causes the solution to contact the mucous membrane. For example, the saline may be delivered by drops, sprays, in a mist, by syringe, such as an ear syringe, or by pump. Pressure in administration is not required and pressure in expelling fluid is not necessary.
[0011] The use of solutions in the salt concentrations taught herein has proven to be especially useful for application to eyes that have become contaminated and irritated by contaminants such as smoke or dust. Use of a mist or wash at the preferred concentration of salt as taught herein proved especially useful for cleansing the surface of the eye.
[0012] The objective in choosing a solution was to find the concentrations at which there was least irritation with good relief of congestion. It was noted that at concentrations above 2.7% there was an immediate relief of congestion; however, when higher concentrations of salt were used there appeared to be a rebound increase in congestion following immediate (short term) relief.
Materials and Methods
[0013] Saline solutions of varying strengths were prepared. The solution was administered as a mist through the nose, and then allowed to flow out of the nose. The following shows the results obtained with various concentration of salt (w/v salt/water).
No irritation − Some irritation + Moderate irritation ++ Severe irritation +++ Effectiveness was determined by subjective relief of congestion
Hypertonic Solutions
[0000]
2.1%—No irritation − . . . Less effective
2.2%—No irritation − . . . Less effective
2.3%—No irritation − . . . Less effective
2.4%—No irritation − . . . Most effective
2.5%—No irritation − . . . Most effective
2.6%—No irritation − . . . Most effective
2.7%—Some irritation + . . . Most effective
2.8%—Some irritation +
2.9%—Moderate irritation ++
3.0%—Moderate irritation ++
3.1%—Severe irritation +++
3.2%—Severe irritation +++
[0031] The concentrations for use on mucous membranes of the nasal tract are also preferred for use in the eye. The application of the solution containing 2.6% sodium chloride as a mist to the eye of a firefighter who had been exposed to contaminants believed to contain asbestos resulted in dislodging of particles, cleansing and relief of irritation.
[0032] Many causes lead to congestion and irritation of the exposed surfaces of the respiratory tract and the eye. Colds commonly trigger congestion, but any factor that causes the mucous membrane to become inflamed may lead to sinusitis. Many people with allergies suffer congestion (allergic rhinitis). Congestion arising from allergies often leads to recurring and/or chronic inflammation of the mucous membranes which can give rise to sinus infections. In fact, any condition which blocks the nasal passages increases the risk of sinusitis.
[0033] Inflamed, congested mucous membranes can also give rise to snoring. The use of saline of the preferred concentrations in accord with the methods of the invention often decreases snoring. The solution pulls fluid from the mucosa and also flushes out germs, contaminants, and pollutants (pollen/dust/sand/soot/smoke, etc.) from the mucus membranes. Mechanical obstruction such as that caused by deviated septum is also a cause of snoring and of irritation to the mucosa. Any obstruction increases likelihood that irritation of the mucosa will occur.
[0034] The use of the solutions in accord with the methods of the invention provides means of prophylaxing against congestion arising from exposure to dust, smoke and other environmental irritants. For example, cleaning the mucous membranes with preferred solutions taught herein after exposure to dust such as that encountered in mining, milling, farming or construction trades can prevent congestion and infection of the mucous membranes. The methods of the invention are particularly useful for cleansing the mucous membranes following exposure to smoke and other contaminants that are routinely encountered by fire fighters and other first responders. Dislodging of fine sand, smoke, ash and soot are important in preventing discomfort and disease.
[0035] The solutions may be applied to the mucous membranes by any means which causes the solution to contact the membranes, such as aerosol, dropper, pump, ear syringe or bag on valve (BOV) containers . A relatively new means of application, the nasal mist pump, has increased both sinus tissue area exposure and the amount of liquid solution being dispensed, resulting in a most effective treatment for reducing sinus congestion. In many instances the low pressure nasal mist pump is the best device for administration of the hypertonic solutions. Additionally, the nasal mist pump is a preferred method of administration because it can be loaded with solution, sealed and sold with the solution protected from exposure to contaminants. These pumps provide a means of thoroughly bathing the membranes in the solution. The use of the nasal mist pump was also quite useful for cleansing the eye of contaminants.
[0036] When the solution is administered to the nasal mucosa as a stream by syringe, it is best to have the head bent over a basin or sink so that the solution may be allowed to flow out through the nose and mouth. When using a pump, dropper or aerosol (most convenient ways for administration) the solution can simply flow into the nose and out again to cleanse and dehydrate the membranes contacted.
[0037] Unlike with the prior invention of Lutin to prevent discomfort in the ears, there is no need to hold the nose while applying pressure. In fact, such application of pressure against a closed nose would not be appropriate in treatment, especially the treatment of children.
[0038] The compositions of the invention need not contain a preservative. In fact, preservative free hypertonic saline at 2.3% to and including 2.7% w/v (preferably 2.4% to and including 2.6% w/v) salt in water is quite effective and has not presented any problem in use so long as the solution is free of contamination. It should be noted that in any case where hypersensitivity or outright allergy is a cause of congestion, it is preferred that the solution be as free of additives as possible.
[0039] Sea salt sold commercially usually has the same amount sodium chloride as commercially sold salt from other sources. However, there are some times contaminants in sea salt. If such contaminants are present, the amount of sea salt required to deliver the full amount of sodium chloride at the w/v indicated herein will vary. Hence, it should be stipulated that the amount of sea salt used should be sufficient to provide the appropriate concentration of sodium chloride and such amount will usually depend on the amount of contaminants in the sea salt. | The optimum concentration of salt in solutions to combat congestion of the mucosa is a relatively narrow range. This use of in hypertonic saline solutions for treatment of congestion of the mucosa having a concentration within the range of 2.3% to and including 2.7% w/v sodium chloride/water with the most preferred concentration being 2.4% to and including 2.6% w/v of sodium chloride in water brings maximum relief of congestion and for cleansing membranes without causing irritation or discomfort. | 0 |
BACKGROUND OF THE INVENTION
This invention pertains to fusion machines and more particularly to improvements in tokamaks.
Tokamaks are machines originally developed by the Russians starting in 1958. After L. A. Artsimovich came to the United States in 1969 and delivered a series of lectures the first American tokamak was built in Princeton in 1970. The goal of these machines is to attain nuclear fusion.
It is known (the Lawson criterion) that such fusion can be attained with a net power release when a plasma which is a fifty percent mixture of deuterium and a fifty percent mixture of tritium with a number density (n) is maintained for a time (τ) so that the combined product is (5×10 14 atoms/cm 3 ×200 msec=10 14 atoms-sec/cm 3 ) and held for this time at a temperature of 100×10 6 degrees Kelvin. If these two conditions of the number density-time product and the temperature are achieved the amount of electrical energy produced by the fusion of the hydrogen isotopes deuterium and tritium will equal the electrical energy required to produce the plasma. In addition, it is required that heat energy of the plasma be recovered and transformed into electricity at 33% efficiency while the plasma itself is electrically heated at 100% efficiency. It is believed that if the values of the number density-time product and the temperature were increased by only a factor of two or three there would be a large ratio of output power over the input power.
The basic design of a tokamak as given by L. A. Artsimovich comprises a stainless steel chamber filled with deuterium gas at low pressure surrounded by a thick copper wall. Surrounding the toroidal chamber are energized windings to induce a toroidal magnetic field B.sub.φ of about 20 kG within the chamber. Additionally, another set of energized windings induces a magnetic field B E directed along an axis which is perpendicular to the plane of the toroidal chamber and which passes through the center of curvature of the torus that defines the chamber. Initially the gas is ionized by radiofrequency signals of about 100 kHz at 20 kW. The magnetic field B E is linearly increased and adjusted at such a rate so that the external electric field is near 0.2 V/cm to minimize the appearance of runaway electrons. This field drives a plasma current that heats the plasma and rises linearly until the plasma current reaches a value of I P =100 kA and the discharge duration reaches about 100 msec. The plasma is thereby heated to about 6×10 6 ° K.
Various modifications and improvements on such machines were made over the years until in 1975 the Alcator tokamak of MIT achieved the values of: n=4×10 14 atoms/cm 3 ; and τ=18 msec.; nτ=0.7×10 13 atoms-sec/cm 3 ; and T=10×10 6 ° K.
Lately these values have changed such that n and τ have increased by about 50% so that nτ has doubled but T has decreased by about 30%.
Presently, tokamaks are rather close to the desired parameters of nτ and T. Some scaling laws suggest that the desired values of nτ will be reached with a B.sub.φ of about 150 kG because the nτ product is proportional to B.sub.φ 4 . This is about twice the field achieved until now. Such high fields exert tremendous forces. Indeed the 150 kG field exerts a force of 6.5 tons/in 2 . In the Alcator tokamak the highest fields achieved are about 85 kG which exerts a force 1/3 of this value. These high fields are technologically achievable, but very expensive to generate. Another problem with present tokamaks is that the plasma pressure contained is somewhat less than 1% of the magnetic pressure. Thus 2 tons/in 2 of magnetic pressure contain a plasma pressure of 20 lbs/in 2 . This is bad not only because of the high capital costs of the magnetic fields, but also because at these low values of β (ratio of plasma pressure to magnetic pressure) the dominant loss from the plasma is synchrotron radiation, which has been neglected in obtaining the values of n, τ and T of the Lawson criterion mentioned above.
Inclusion of this loss due to synchrotron radiation alters the Lawson Criterion to higher values of T and furthermore the fusion power output comes uncomfortably close to the synchrotron radiation output. Thus the margin for inefficiencies is much less. Detailed calculation by many authors has shown that the synchrotron radiation problem is minimal for a β of at least 0.1. This value would also minimize the capital cost of a reactor. Thus values of about 20 times the best present tokamak values are needed.
These values are partly related to the main method of heating the plasma, by driving a current of 100,000 A through it. Use of the neutral beam technology provides modest increases in β, perhaps factors of 2, but larger values seem unlikely.
SUMMARY OF THE INVENTION
It is known that the plasma parameters n, T and τ are determined mainly by the plasma current. However, the maximum value of such current I in amperes is limited by the Kruskal-Shafranov relation: ##EQU1## where R is the orbital radius and a is the radius of the cross section of the toroidal chamber. Thus, the attainable value of B.sub.φ limits the maximum value of the plasma current I and consequently the plasma parameters. Instead of using higher toroidal fields B.sub.φ with all their disadvantages to stabilize the plasma current this invention uses a magnetic field which is weaker than B.sub.φ.
This weaker magnetic field can be obtained from the strong focusing (s.f.) concepts elaborated by Courant et al. in Physical Review of 1952, at page 1190 and by U.S. Pat. No. 2,736,799 of N. Christofilos wherein the strong focusing was used for conventional particle accelerators such as synchrotrons. It should be noted that present tokamaks operate with a weak focusing (w.f.) field which is a cylindrically symmetric magnetic field at the orbit of the plasma current to keep the current channel fixed. This weak focusing field is quite weak, much weaker, for example, than the focusing produced by the magnetic field of the plasma current. This weak focusing magnetic field although sufficient to hold the plasma current channel in place, is not sufficient to stabilize against the Kruskal-Shafranov instability. A strong focusing magnetic field of strength 10 times larger than w.f. field should stabilize a plasma current channel with an aspect ratio R/a 5. Under these circumstances the s.f. force is about equal to the focusing of the current channel magnetic field (B s ), for the circulating particles.
Thus, the invention contemplates replacing the toroidal magnetic field of a tokamak with a strong focusing magnetic field. This strong focusing magnetic field is generally localized in the region of the toroidal chamber. To obtain the strong focusing the field itself is azimuthly non-uniform and in fact regularly varies in polarity for different azimuth positions. Such a fusion machine is hereinafter called a S. F. Megatron.
BRIEF DESCRIPTION OF THE DRAWING
Other objects, the features and advantages of the invention will be apparent from the following detailed description when read with the accompanying drawing which shows by way of example not limitation the presently preferred embodiment of the invention. In the drawing:
FIG. 1 is a top view partially in schematic of the nuclear fusion system in accordance with the invention
FIG. 2 is a cross-sectional view taken along the line 2--2 of FIG. 1;
FIG. 3 is a cross-sectional view taken along the line 3--3 of FIG. 1;
FIG. 4 is a schematic diagram illustrating the reference coordinate system used in establishing magnetic field criteria;
FIG. 5 is an enlarged view of a side of a magnet section; and
FIG. 6 is a graph showing the build up of currents as a function of time for establishing the plasma current and the focusing fields.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1 there is shown a top view of the fusion machine 10 including a multisection toroidal chamber 12 of preferably circular cross-section. Each of the sections 12a, 12b, 12c, etc. is preferably made of stainless steel having a thickness of about 0.5 mm. The sections are joined together by ceramic rings 14 which provide an air tight seal and electrical isolation between adjacent sections. Typical dimensions for radius R from the axis of revolution C to the median region within the cavity can be about 100 cm and the radius a of a circular cross section of the chamber can be 20 cm. Thus, a desirable form factor or aspect ratio R/a is about five.
Connected to section 12c is a vacuum pump 16 for evacuating the chamber 12 before introducing the hydrogen isotope gas from source 18 connected to section 12a. The gas is preferably a fifty-fifty mixture of tritium and deuterium. Radiofrequency energy source 19 is connected to a large loop on chamber 12 for initially weakly ionizing the gas to provide current carriers.
Positioned within the outline of the toroidal chamber 12 is the solenoid 16. The solenoid 16 has a plurality (about 8000) of turns concentric with the axis of revolution C. The windings have a radius of about 40 cm. and are about 1.25 cm thick and made of super-conducting wires carrying about 40 kA/cm 2 . The solenoid has a length of about 160 cms symmetrically disposed about the plane of the chamber 12 to provide a substantially axial magnetic field. The solenoid 16 is connected to controlled current source 18 so that when an increasing current (up to about 1 kA) is delivered to the turns, the axial or inducing magnetic field is generated. This increasing magnetic field induces a plasma current which circulates around the chamber according to usual tokamak system. However, this current must be stabilized.
The stabilization according to the invention is achieved by replacing the usual tokamak toroidal field B.sub.φ by a strong focusing field. In particular, a special magnetic field is established between two planes which straddle the toroidal chamber 12. This special focusing field is generally in the Z direction and as seen from FIGS. 2 and 3 is alternately bowed concave and convex. The field lines pass through the toroidal chamber from below and exit above it.
It should be noted that weak focusing by a vertical magnetic field B f at the location of the plasma channel was used at Princeton ATC tokamak. In the z=zero plane this field is given by. ##EQU2## where r o is the equilibrium position of the average circulating particle (see FIG. 4), r the radial coordinate of the particle, B o the field at the equilibrium position, and n the field index ranging between zero and one. However, this weak focusing field cannot stabilize against the Kruskal-Shafranov instability. To provide such stabilization the field according to the present invention is strong and not uniform in the azimuthal (φ) direction. In fact it periodically varies in amplitude and direction to focus and defocus the circularing particles in their circular orbit in the chamber 12. This strong focusing field is generated by a plurality of pairs of magnet sections 20D and 20F. The number of pairs of sections and the fields established by these sections will now be derived making use of the techniques of Green and Courant in Handbuch der Physik, S. Flugge, ed. Vol. 44, 1949 in conjunction with the coordinate system of FIG. 4. The effective force on an orbiting particle is given by ##EQU3## where m is the mass of the particle, e its charge, B o is the same as in Eq. (2), and x is the radial deviation of the orbit from the equilibrium position, r o . We now obtain the quantity ν. The ratio of the s.f. to w.f. forces is: ##EQU4## where ν is the normalized frequency.
The s.f. force should be larger than the w.f. force and preferably 10× larger. Thus the range
1<2ν.sup.2 ≲10 (5)
exists for ν 2 . The general relation ν=μN/2π also holds, where N is the number of magnet pairs. At the optimum operating point, μ≃π/2, giving ν≃N/4, so that using the upper limit in Eq. (5), 2ν 2 ≲10, one obtains ν≲2.24 and N≃4ν≃8.94 or N=9, since N must be an integer. With the lower value of ν 2 in Eq. (5) one is led to N≃2.83 or N=3. I prefer to use the value N=8 (i.e. 8 magnet section pairs) in the present embodiment, due to the appeal of symmetry, although the system can also work with as few as 3 magnet section pairs. (Note that the minimum number N required to have a strong focusing device is N=1, i.e. only one magnet pair.)
The field index, defined in Eq. (2), is given approximately through n≃N 2 /4=16, using the design value N=8, noting however that it may be as low as n≃4.5 for N=3 and lower for N=1.
This completes the coarse specification of the number of pairs of magnet sections and the field index. More precise specification is however required to ensure that resonances do not occur among the three frequencies, the axial (z), the radial (x) and azimuthal (φ) which could destroy the beam. These resonances have been worked out by P. A. Sturrock (Ann. of Phys. p. 113; 1958) and by E. D. Courant and H. S. Snyder (Ann. of Phys. p. 1; 1958) and summarized in the Handbuch der Physik article mentioned above. It is shown therein that to avoid resonances between the axial and radial frequencies, one must avoid the values (ν x >0, ν z >0)
ν.sub.x +ν.sub.z =k.sub.o (6)
while to avoid the resonances between the axial or radial frequencies and the azimuthal rotation frequency, one must avoid the values ##EQU5## where the k i are arbitrary positive integers. Additional resonances arise from consideration of quadratic terms in the equations of motion. These give instability for
k.sub.1 ν.sub.x +k.sub.2 ν.sub.z =k.sub.o, k.sub.1 +k.sub.2 =3 . (8)
For k 1 +k 2 =4 there is possible instability while for k 1 +k 2 ≧5 the system is stable. Again all the k i are positive integers, but k 1 or k 2 =0 is also allowed in Eq. (8). When ν x =ν z the values of ν to be avoided, near ν≃2, are from Eqs. (6), (7), and (8)
ν=1.5, 1.667, 1.75, 2., 2.25, 2.333.
The width δν for which instability exists, at least for the case of Eq. (7), is roughly ##EQU6## A convenient value of ν is, ν=2.13 so to comfortably avoid the above resonances δν<0.12 is needed. In the present case with N=8 and n≃16, this implies Δn/n<0.09. For safety, one should require a smaller value, say Δn/n≃3%, to avoid the resonances.
Now consider the exact equations for ν x and ν z . These are, ##EQU7## and typically n D >>1, n F <<-1. It should be noted that n D is the field index for a defocusing section and n F the field index for a focusing section. Equation (10) assumes that the D and F magnet sections are equal in length, which tends to be the optimum. Since the chamber of the present system has a rather small aspect ratio, i.e. R/a≃5, unlike the typical accelerator values R/a≃1000, it may be desirable to make the D magnet sections (with larger fields on the inside) somewhat longer and the F magnet sections (with field larger on the outside) somewhat smaller, to minimize the total field energy. When the sections are of unequal length the α variables are changed to,
α.sub.1 →α.sub.1 l, α.sub.2 →α.sub.2 (1-l), α.sub.1 →α.sub.1 (1-l), α.sub.2 →α.sub.2 l (12)
where ##EQU8## and L D and L F are the lengths of the D and F magnet sections respectively.
To obtain ν x =ν z , it is seen from Eqs. (10) and (11) that one must set
n.sub.D =1-n.sub.F. (14)
With this result and the values ν=2.13, and N=8, one finds that n D =16.27. However a plot of the magnetic field produced by this value of n D , shows that the value of field B z reverses directions as |z| increases from 0 to `a` within a toroidal chamber of aspect ratio R/a=5. As this is undesirable, one chooses the lowest field index that maintains the same direction for the field B z . (The field lines will be discussed in more detail hereinafter). This value is somewhat above n D =7, but I will choose this odd integer value for its convenience, as will be seen later. However, it should be noted that n D can range between 4.5 and 8. Inserting this value into Eqs. (10), (11) and (14), gives however an imaginary (i.e. unstable) value for μ. One can however recover stability by introducing straight sections, i.e. sections without magnetic field. In addition, different magnet sections are needed to produce the positive and negative field gradients and they thus must be physically separate.
The region where the field falls to zero is approximated as an additional straight section. Each magnet section is now assumed to be a magnet of length l m (either focusing or defocusing) followed by a field free region (straight section) of length `s`. I now define s≡s/l m . The addition of straight sections changes the equations for cos μ x and cos μ z . Thus, there must now be added the terms [cos μ x ] a and [cos μ z ] a to the right hand sides of the equations for cos μ x and cos μ z , respectively, of Eq. (10). These additive terms are, from J. J. Livingood, p. 204 (`Cyclic Particle Accelerators', D. Van Nostrand, Princeton, N.J.; 1961),
[cos μ.sub.x ].sub.a =s(α.sub.1 sin hα.sub.1 cos α.sub.2 =α.sub.2 cos hα.sub.1 sin α.sub.2)-(s.sup.2 /2)α.sub.1 α.sub.2 sin hα.sub.1 sin α.sub.2 ≡F(α.sub.1, α.sub.2)[cos μ.sub.z ].sub.a =F(α.sub.1, α.sub.2). (15)
It is thus found from Eqs. (10), (11), (14) and (15), that when
s=0.695, n.sub.D =7, n.sub.F =-6 and N=8 (16)
the desired value ν=2.13 is obtained. In this region δν≃2≃s, so that the requirement δν<0.12 implied by Eq. (9) means that δs≃0.05 is needed which gives for the necessary accuracy in δs/s=δs/s≃7%.
There will now be considered the actual shape of the magnet sections required to produce the field indices of Eq. (16). Owing to the required magnet shapes it is difficult and expensive to produce the fields using shaped iron pole pieces with current windings. It is preferred to use current windings on the surfaces formed by rotating the B lines in the φ direction. These surfaces are equivalently, the flux surfaces, i.e. the surfaces of constant flux. In a φ=constant plane, these curves are
rA.sub.φ =constant (17)
since Φ=2πrA.sub.φ is the flux through a radius r and A.sub.φ is the vector potential.
Rather than find A.sub.φ through the solution of ∇×∇×A.sub.φ =0, it is easier to proceed indirectly. First, there is solved the equations ∇ 2 V=0 with B=∇U to obtain the magnetic potential ##EQU9## in cylindrical coordinates for arbitrary `n`. This result is obtained by applying successively, ∇×B=0 on Eq. (2) to find the next higher order term in B r and then using ∇·B=0 to find the next higher order term in B z . After the series in B z is established integration gives V. This series converges only for z<r, unless `n` is a negative even integer, in which case the series is finite.
This expression for V, aside from a constant, may be written in spherical coordinates, r and θ, in closed form when m>0 is an odd integer, ##EQU10## where the P m are the usual Legendre polynomials. Only odd integers are permitted because V, in Eq. (18), is odd in z=r cos θ. Note the relation between `n` and `m`,
m=1-n (n<0), m=n-2 (n>0). (20)
Noting that B=∇×A=∇V, one can integrate B.sub.θ to find A.sub.φ. This gives, again in spherical coordinates (r sin θ=r), ##EQU11## also for m>0 and m is an odd integer. One may also obtain the appropriate series in cylindrical coordinates by finding B through Eq. (18) and then integrating B z =(∇×A.sub.φ) z in cylindrical coordinates to obtain A.sub.φ. This gives ##EQU12## Aside from constants B 0 and r 0 , this expression must be multiplied by the constant k m where ##EQU13## to obtain Eq. (21). Equation (18) must also be multiplied by the same constant k m to obtain Eq. (19). One may also use Eqs. (19) or (21) to obtain the appropriate analytic continuation of Eqs. (18) or (22).
There is now seen the utility of choosing n D =7, an odd integer and n F =-6, an even integer. It allows the use of the exact expressions, Eqs. (17) and (21) to calculate the field lines. The appropriate value of `m` to be used in Eq. (21) is obtained from Eq. (20). Several field lines have been plotted in FIGS. 2 and 3 using Eqs. (17) and (21). The magnetic field itself is however, obtained more easily from the magnetic potential, Eq. (19) than the vector potential, Eq. (21), and is in spherical coordinates ##EQU14## The current required to produce this field is obtained by noting that one may take any field line or better, flux surface, wipe out the magnetic field on one side of it and place a sheet current on the flux surface with magnitude and direction appropriate to produce the desired field jump across the sheet. The required current sheet, K, is given by ##EQU15## where n is a unit vector from the surface into the region with nonzero B and amp signifies that the units of K amp are amperes/cm. Also K amp =I amp /Δl where Δl is measured along the field line. Since n is perpendicular to B, the direction of K is in the ±φ direction with its magnitude given by ##EQU16## with ##EQU17## where `m` and `n` are related as in Eq. (20). There is shown in FIGS. 2 and 3 flux surfaces.
The current sheet may be approximated by discrete currents, each occupying a band of a width Δl=0.01 r 0 where as before, Δl is the distance along the field line. (If r 0 =1 meter then Δl=1 cm.)
The current variations indicated by Eqs. (25) and (26) may be obtained either by varying the current in each band according to the average value of each band as found by the equations, or by keeping the current constant and varying the band separation or density. The choice between the two methods will depend on the economics or convenience. More detail on the currents will be given below.
As seen from FIG. 5 the bands or tapes 40 are fed by a common buss and mounted on a non-conductive form 44.
From FIGS. 2 and 3 it can be seen that the variation of current from winding to winding is in the range 5%-30%, with the larger field and current variations occurring in the `web` between the lobes. Still, the fineness of this mesh should produce a field gradient error of less than 1% within the torus. Truncating the current sheet at |B|=3.5 for the n D =7 magnet and at |B|=3.0 for the n F =-6 magnet should also produce a change of less than 1% in the field index within the toroidal chamber.
The truncation of the flux surface for the windings from the ideal surface, is somewhat arbitrary, but should give a smaller error than demanded by Eq. (9). The choice of flux surfaces is subject to two constraints. One is that they must lie outside the toroidal chamber and the other is that the maximum value of K be as small as possible. Thus in general the flux surfaces should lie as close to the torus as possible. Three lobes are shown in FIGS. 2 and 3, although from Eq. (21) there exist 2 m+1 lobes in the right half plane. Neglect of the other lobes should not unduly perturb the desired field within the toroidal chamber.
The above specification of the field was calculated on the assumption that the field is azimuthally symmetric. This is, of course, not exact, although we do not expect the exact magnetic field to be much different from that shown in FIGS. 2 and 3. However, in any case the field need only be accurate enough so that Eq. (9) be satisfied. The important point is that it has been shown that one can produce magnetic fields with the dependence shown in Eq. (2) over large regions.
Having now specified the values of `n`, N and s for the s.f. system, I now specify next the value of B 0 in Eq. (2). Its value is the same as in the w.f. case. When B 0 is in gauss, r in cms. and I, the plasma current, in amperes, we have ##EQU18##
I will describe now the appropriate values of field, B E , whose time rate of change produces E.sub.φ, the toroidal electric field that drives the plasma current. Since the field gradients at the torus have been specified above and are given by a specific set of magnet sections, it is convenient if the field B E does not perturb this result. This may be done by requiring the field B E to be zero within the toroidal chamber 12. Such a field is produced by a solenoid 16 of height h s =4a s where a s is the radius of the solenoid and equal to 0.4 r 0 . (The axis of the solenoid is the same as the z axis of FIG. 1). The stray field in the vicinity of the torus could be reduced by increasing the solenoid height, but only at the cost of increased magnetic energy which is proportional to h s , the height of the solenoid. If the stray field is too large with the above solenoid shape, one could use a pair of Helmholz coils near the torus to cancel the stray field.
I next turn to the calculation of the magnitude of the field, B E . The magnetic field in the z=0 plane of the solenoid is given by ##EQU19## where n l is the number of windings per unit solenoid length and I E is the solenoid current in amperes. The upward flux in the z=0 plane in the solenoid, Φ; is given by
φ=B.sub.E (πa.sub.s.sup.2). (2A)
Since this is the same as the flux through the circle r=r 0 , the electric field at the torus center (in the φ direction) is given by ##EQU20## where E is in volts/cm and the units of B and r are gauss and cm.
Combining Eqs. (1A) and (3A) now gives ##EQU21## To obtain I E ≃ΔI E /Δt, I next consider the value of the electric field, E. It should ordinarily be as large as possible to maximize power transfer to the plasma. However when E becomes too large, then many runaways are produced and instabilities are excited that increase the effective collision rate and hence the effective resistance. This causes the plasma to diffuse faster across the magnetic field and decreases the power transfer to the plasma, so that the plasma cools and is lost. The critical field (Dreicer field) above which the number of runaway electrons increases sharply is
E.sub.c =7×10.sup.-14 nΛ/T≃1.0×10.sup.-12 n/T (5A)
where Λ≃15, n is the plasma density in cm -3 and T is the plasma temperature in ev. The initial plasma density, for typical tokamaks, just after the RF preionization, is about 10 12 /cm 3 while T≃1 ev so that E c ≃1.0 v/cm. The induced electric field rapidly completes the ionization so that the density rises to about 10 13 /cm 2 while T rises to about 5 ev so that E c ≃2 v/cm. It is found experimentally that
E≃0.15 v/cm (6A)
is sufficiently low to eliminate the runaway electrons. Although T continues to rise to ˜1 kev, the self-magnetic field of the plasma tends to cancel the applied electric field, so that the actual electric field E a , is only several percent of the applied electric field and E a <<E c remains true.
Using Eqs. (4A) and (6A) one can find the desired value of I E . To obtain the maximum value of I E there is needed a relation connecting it to the plasma current I p . This may be obtained from the following considerations. In a betatron accelerator equilibrium requires that the average magnetic field B E , within the average particle radius r 0 , be twice the field at r, i.e. B E =2B 0 . In a tokamak one would expect a larger value of B E in order to compensate both for the cancelling effect of the self-field and the loss of angular momentum due to collisions. Remarkably, the additional factor for B E , or equivalently the magnetic flux, is only twice what it is in the Betatron. This is experimentally observed and is due to the fact that the self-field almost cancels the applied field, as will be seen hereinafter. Thus for the tokamak
B.sub.E =4B.sub.0 (7A)
while from Eqs. (1A) and (2A), ##EQU22## Inserting this result into Eq. (7A) and the value of B 0 from Eq. (27) gives the desired result ##EQU23## using the typical values, g≃3, r 0 /a s =2.5. If, further a s ≃0.4 m and I p ≃10 6 amps, as is preferable for a fusion reactor, then
n.sub.l I.sub.E ≃25 kamps/cm. (10A)
Since a 1 cm diameter wire can carry 1 kamp (with the aid of some cooling water) this implies that one needs 25 turns per cm, i.e. the number of turns on the solenoid must be 25 deep. Using superconductors would of necessity decrease the thickness of the solenoid.
I now determine the time Δt, that the linearly increasing solenoid current must be maintained. To find it I insert the result, Eq. (9A) into Eq. (4A) to obtain ##EQU24## using also the value of E from Eq. (6A). With the largest present day machines where I p ≃1.×10 5 amps, this implies that Δt=I p /I p ≃4 msecs while for a fusion reactor where I p ≃10 6 amps, Δt≃40 msecs. (Note that Eq. (11A) is equivalent to V=-LI p where L is the inductance, L=4πr 0 g/c 2 in cgs units, so that V+E(2πr 0 )≃0 and the changing current tends to cancel most of the applied field.) From the linear relation of Eq. (9A) the rise time, Δt of the solenoid and plasma currents, is the same and is so shown in FIG. 7.
To obtain a net fusion energy production, as mentioned above, a containment time Δt c ≃200 msecs is necessary. Multiplying this by 2 to obtain a comfortable margin, gives Δt c ≃400 msecs for the second or plateau phase. This is about 10× the duration of the first phase, the time required for the plasma current to reach the desired value of 1 million amperes. The electric field needed for this second phase is roughly proportional to the ratio of the two times, and is given by ##EQU25## Thus in FIG. 6, the current increment in the second phase, from 40 to 400 msecs equals the current increment, ΔI E in the first phase from 0 to 40 msec and the final current in the solenoid coil, I E is twice that obtained from Eq. (10A) so that n l I E ≃50 kA.
I now calculate the explicit numbers for the current required to produce the alternating gradient fields of FIGS. 2 and 3, for the specific parameters
r=100 cms, I.sub.p =10.sup.6 amps. (1B)
From Eqs. (24), (25) and (26) ##EQU26## The value of B 0 is obtained from Eq. (27) using the data of Eq. (1B), giving ##EQU27## while for the spacing Δl we use Δl=0.01r 0 =1 cm.
By way of example I now calculate the current needed on the surface of the coil lobe of FIG. 3, at the point r=0.725 r 0 , z=0, labelled |B|=1 in the Figure. Since θ=π/2, and n=7 then P 5 =0, while P 5 '/k 5 =1 so that from Eq. (3B)
b=9.50. (5B)
Combining this with Eqs. (2B) and (4B) gives the current ##EQU28## Since the current is proportional to |B|, the current at others points of the coil can be similarly calculated.
Since a 1 cm 2 area wire can carry a steady current of about 0.5 kA, with water cooling (e.g. PLT tokamak toroidal coils) we see that the surface current winding must be 46 cms deep. This is however too large for the scale of the coil shape in FIG. 3 and one must go to superconducting coils that can carry much higher currents ˜40 kA/cm 2 (manufactured by Vacuumschmelze Hanau, Phys. Today July '77, p. 38). The current winding is then only 0.6 cms deep at z=0 and 2.0 cms deep at the web where |B| is 3.5× larger. This current thickness is sufficiently small to approximate the current sheet of the coil form of FIG. 3.
It is also possible to use normal conductors if the scale length r 0 is increased considerably, at least a factor of 3. This decreases B 0 through Eq. (4B) and increases the scale of FIG. 3 by the same factor. Hence the effective current winding depth is reduced by a factor of 3 2 . The choice of normal or superconductor must rest solely on the economics of the situation. The currents for the solenoid 16 are generated by controlled current source 18 under control of controller 19 to produce the current waveform I E of FIG. 5. The currents for windings of the focusing magnets are generated by controlled current source 30 under control of controller 19 to produce the current waveform I f of FIG. 5. The energy for generating these currents can be stored in electrolytic capacitors or in large flywheels that drive commercial electric generators.
It should be noted that by using the strong focusing as described above β is greater than unity and therefore much greater than the required minimum value 0.1. Thus the strong focusing megatron of the present invention gives quite large values of β for synchrotron radiation, large enough to neglect the effect of this radiation on the power balance of a tokamak and hence this s.f. megatron will allow the construction of an economic fusion reactor. | A strong focusing megatron has a hollow toroidal chamber in which a plasma of isotopes of hydrogen support an orbital current driven by a changing magnetic field whose amplitude is controllably variable and whose direction is generally coaxial with the major axis (z-axis) of the toroidal chamber while the current is stabilized by a strong focusing magnetic field of alternately focusing and defocusing sections whose field is generally in the region of the toroidal chamber. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a cooling air bleed device in a turbine engine, such as an airplane turbojet, which is intended in particular for cooling flaps of a convergent-divergent jet nozzle.
The jet nozzle of a turbojet generally comprises mobile flaps that are subjected to strong thermal stresses due to the passage of very hot gases coming from the combustion chamber of the turbomachine. These thermal stresses generate large amounts of infrared radiation capable of hindering the stealth of military aircraft and that should be minimized.
A solution consists of bleeding cold air in a secondary flow of the turbomachine, so as to direct it toward the flaps of the nozzle and cool them.
2. Description of the Related Art
The patent application EP 1 522 680 of the applicant describes a system for ventilating mobile flaps of a convergent-divergent nozzle of an airplane turbojet, which system includes an annular conduit supplied with cooling air through orifices provided in a wall separating the interior of the conduit from the downstream end of an annular passage surrounding a post-combustion chamber of the turbojet and in which a cooling airflow circulates. This ventilation system also includes air distribution cells distributed around the conduit and connected thereto, and telescopic channels each connecting a cell to a divergent nozzle seal located in the same plane of symmetry as the cell.
The disadvantage of this system is that it does not enable the bled airflow to be modulated.
This air bleed adversely affects the performance of the turbojet and is generally unnecessary in all phases of the aircraft flight.
BRIEF SUMMARY OF THE INVENTION
The invention is intended in particular to provide a simple, economical and effective solution to this problem, in particular enabling the airflow bled to be modulated at will in order to cool the nozzle.
It relates in particular to means for supplying cooling air in a turbomachine, located at a short distance upstream of the nozzle flaps, and which are capable of withstanding significant mechanical stresses generated by the thrust of gases in this location, and significant deformations of the nozzle due to high thermal stresses.
The invention also relates to means for supplying cooling air that are low profile and relatively lightweight, and that enable disturbances in the airflows flowing into the turbomachine to be limited, so as to optimize the performance of the turbine engine.
It also relates to cooling air supply means that are manually controlled by the airplane pilot.
The invention thus proposes a cooling air bleed device for cooling components in a turbomachine, including an annular conduit formed in a housing and having a radially internal portion that is swept by an airflow moving from upstream to downstream and that comprises at least one air inlet orifice with a radial axis, which device includes a flap valve for controlling the airflow entering through the orifice, and wherein the flap valve is formed by a plate held at its periphery by a maneuvering member outside the orifice and mobile in translation parallel to the axis of the orifice between a position in which the plate is applied on the edge of the orifice and closes off said orifice and a position in which the plate is moved away from the orifice and opens said orifice.
In the closing position, the plate is held against the edge of the orifice and closes the latter tightly under the pressure of the airflow.
The opening and closing of the plate result from a translation movement of the latter according to the axis of the orifice, thereby enabling the wear of its surface applied on the edge of the orifice in the closing position to be minimized, and therefore the lifetime of the device to be improved.
According to another feature of the invention, the airflow is guided toward the orifice of the conduit by an oblique wall attached to the housing by means forming a stop limiting the movement of the plate of the flap valve in the direction of opening of the orifice.
The oblique wall enables the movement of the airflow to be facilitated and the disturbances and head losses thereof to be limited, thereby enabling the performance of the turbomachine to be optimized.
The surface of the plate of the flap valve intended to be applied on the edge of the orifice advantageously comprises a seal, which preferably has a stainless steel sheet structure inserted between graphite layers or a graphite metal screen structure.
According to another feature of the invention, the maneuvering member includes a ring with a cylindrical internal threaded surface, cooperating with means formed in the housing for guiding the ring in translation and locking it in rotation, with an end of the ring being connected to an end of the plate of the flap valve.
The locking in rotation of the ring can enable the latter to be driven in translation by a screw-nut effect, as demonstrated below.
The means for locking the ring in rotation preferably include at least one lug or a longitudinal rib engaged in a longitudinal groove formed on the external surface of the ring.
Alternatively, the ring has an external polygonal cross-section and is housed in a cavity of the housing which extends parallel to the axis of the orifice and which has an internal cross-section substantially identical to the external cross-section of the ring in order to lock the ring in rotation.
According to another feature of the invention, the valve includes a toothed wheel for rotating a threaded rod screwed into the ring of the maneuvering member and held securely in translation by the housing.
The threaded rod cooperates with the internal threading of the ring in order to drive the ring in translation by a screw-nut effect. The aforementioned means for locking the ring in rotation participate in this screw-nut effect, by preventing the rotation of the ring and by guiding it according to a pure translation movement.
The toothed wheel is rotated by controlled means, including for example a flexible cable maneuvered by a cylinder.
The valve advantageously includes a disengageable connecting ring that is mounted coaxially and superimposed on the toothed wheel and secured in rotation with the threaded rod, and that comprises teeth with oblique flanks intended to cooperate by meshing with teeth having a conjugated shape formed at one end of the toothed wheel opposite the teeth of the connecting ring, and the valve also preferably includes resilient return means axially pushing the teeth of the toothed wheel engaged with those of the connecting ring.
During opening or closing of the flap valve, when the latter reaches the end of course against the means forming a stop or against the edge of the orifice, the connecting ring enables the rotation of the toothed wheel to be decoupled from that of the threaded rod, and therefore from the translation of the flap valve maneuvering member, so that the toothed wheel can optionally continue its rotation without risk of damaging the flap valve.
According to another feature of the invention, the air bleed device is installed on the housing of the turbine engine in order to cool control flaps of a jet nozzle, and it preferably includes a series of flap valves that are distributed uniformly around the axis of the turbomachine and a control actuator connected to the flap valves by synchronous drive means, such as, for example, a flexible cable or a ball cable, connected in series to the flap valves.
The flap valves of the air bleed device described above enable a simple movement of means for driving these valves to be converted into a movement of opening or closing of each of the flap valves, thereby enabling control of the device by a single simple drive means, which can moreover advantageously be chosen to be flexible, such as a ball cable, so that this device withstands deformations of the housing on which it is mounted and any mechanical stresses generated by the pressure of surrounding gases. The valves of the air bleed device according to the invention are capable of being used under these conditions, in particular temperature, which prohibit the use of electrical control valves, as is for example the case in the vicinity of a turbojet nozzle. These valves also have the advantage of having a low profile, and thus enabling the aerodynamic impact of the air bleed device on the flow of gases in the vicinity of the device to be limited. These valves are moreover uniformly distributed around the housing so as to enable uniform air bleed all around said housing.
The invention also relates to a turbine engine equipped with an air bleed device of the type described above.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be easier to understand, and other details, advantages and features thereof will become clearer in view of the following description, provided by way of a non-limiting example, in reference to the appended drawings, in which:
FIG. 1 is a partial diagrammatic view of an air bleed device according to the invention mounted on a turbojet nozzle with a closed flap valve; an upper left-hand portion of this figure is a frontal view while the remainder of the figure is a cross-section view according to a median axial plane of a valve of said device;
FIG. 2 is a partial diagrammatic cross-section in perspective of the jet nozzle equipped with the air bleed device of FIG. 1 ;
FIG. 3 is a partial diagrammatic view of an air bleed device according to the invention mounted on a turbojet nozzle with an open flap valve; an upper left-hand portion of this figure is a frontal view while the remainder of the figure is a cross-section view according to a median axial plane of a valve of said device.
DETAILED DESCRIPTION OF THE INVENTION
Reference is first made to FIG. 1 , which shows a cooling air bleed device 10 mounted on the housing 12 of the afterbody of an airplane bypass turbojet comprising a post-combustion chamber 14 , upstream of controlled flaps and nozzle seals of a jet nozzle, equivalent to the device described in document EP 1 522 680 cited above.
The device 10 includes an air circulation chamber 16 defined by a conduit 18 having a general annular shape and a rectangular axial cross-section, formed on the external surface of the housing. This conduit 18 includes orifices 20 with a radial axis 21 formed in its radially internal wall 22 and intended for bleeding cooling air onto a secondary cool airflow 24 moving from upstream to downstream around an annular wall 26 defining the post-combustion chamber, in which the conduit 18 also includes other orifices 28 formed in its radially external wall 30 and connected to means 32 for routing and diffusing the air over the nozzle flaps to be cooled, in which said means 32 can, for example, be of the type described in the aforementioned prior art document.
An annular wall 34 extends between the downstream end of the external wall 26 of the post-combustion chamber 14 and the radially internal wall 22 of the conduit 18 . This wall 34 is attached by rivets 36 to an annular flange 38 formed at the downstream end of the radially internal wall 22 of the conduit, and divides the secondary cool air flow 24 into a radially external flow intended to supply the bleed device 10 in order to cool divergent flaps of the nozzle, and a radially internal flow intended to cool convergent flaps of said nozzle, as already described in the aforementioned prior art.
According to the invention, the radially internal wall 22 of the annular conduit 18 includes flat portions in which the aforementioned air inlet orifices 20 are formed, so that the latter are flat.
To enable control of the cooling airflow bled, each air inlet orifice 20 is closed off by a flap valve 40 , which includes means for driving a flapper 42 of the valve in translation according to the axis 21 of the orifice, between a position of opening shown in FIG. 3 , and a position of closing the orifice 20 by said flapper 42 shown in FIG. 1 , as described in greater detail below.
The flapper 42 includes an external circular disk 44 with a larger diameter, perpendicular to the axis 21 of the orifice and of which the periphery is intended to be applied against a seat or an edge of the orifice 20 in order to close off the latter, and an internal disk 46 with a smaller diameter formed on the external disk 44 . The periphery of the external disk 44 intended to be applied against the edge of the orifice 20 is covered by a seal 47 , made for example of a stainless steel sheet inserted between two graphite sheets, according to a structure sometimes called “Papiex”. The seal can also be graphite with a metal screen.
The external disk 44 of the valve is secured at its periphery to a lug 48 forming the closed end of a ring 50 intended to maneuver the flapper 42 in order to open and close the orifice 20 .
This ring 50 is housed, centered and guided in a path with a square internal cross-section 52 having an axis 54 substantially parallel to the axis 21 of the orifice 20 and formed on the external surface of the housing 12 .
The ring 50 is mobile in translation according to the axis 54 and has a square external cross-section substantially conjugated with the internal cross-section of the vent 52 .
At its end opposite the lug 48 of the flapper, the ring 50 comprises a cylindrical internal threaded channel 56 into which the threaded end 58 of a rod 60 rotationally mounted in the vent 52 is screwed.
The rod 60 comprises a circular collar 62 intended to enable it to be locked in translation parallel to the axis 21 of the orifice in the radially outward direction of the turbojet, i.e. toward the top of FIG. 1 . For this, the vent 52 comprises, at its radially external end, a shoulder 64 of its internal surface against which the collar 62 abuts.
The locking of the rod 60 in translation radially inwardly with respect to the turbojet is ensure by rotating members mounted on a portion of the rod outside the vent 52 , as will be demonstrated more clearly below.
To facilitate the guiding of the rod 60 in rotation, a sleeve 66 with a cylindrical internal cross-section is mounted around the rod 60 so as to be interposed between the rod and the shoulder 64 of the vent 52 . The sleeve 66 has a square external cross-section conjugated with the internal cross-section of the shoulder 64 of the vent, and comprises a collar 68 with a square external cross-section conjugated with the internal cross-section of the vent, with said collar 68 being interposed between the collar 62 of the rod and the shoulder 64 of the vent.
The collar 62 of the rod 60 divides the latter into a first threaded portion 58 extending into the vent 52 and screwed into the internal channel 56 of the ring 50 , and a second portion 70 extending outside of the vent 52 and bearing a toothed wheel 72 for driving in rotation.
The toothed wheel 72 has radial teeth 74 intended to be engaged with suitable drive means 76 , of which an example will be described in greater detail below, and which are shown diagrammatically in FIG. 1 by teeth 78 cooperating by meshing with the teeth 74 of the toothed wheel 72 . This toothed wheel is also held on the rod 60 by a nut 80 screwed at the end of the latter.
The valve 40 advantageously includes a disengageable connecting ring 82 coaxial to and superimposed on the toothed wheel 72 , and comprising teeth with oblique flanks 84 intended to cooperate by meshing with teeth 86 having a conjugated shape formed at one end of the toothed wheel 72 opposite the teeth 84 of the connecting ring 82 .
Resiliently deformable washers 88 , such as wave or frustoconical washers, for example numbering three, are interposed between the toothed wheel 72 and its retaining nut 80 on the rod 60 , in order to axially push the teeth with oblique flanks 86 of the toothed wheel 72 against the teeth 84 of the connecting ring 82 and thus cause the toothed wheel to be rotationally secured with the connecting ring.
The connecting ring 82 includes splines (not visible in FIG. 1 ) extending radially over its internal face and cooperating with splines (also not visible) with a substantially conjugated shape formed on the second portion 70 of the rod 60 in order to transmit to said rod the rotating movement of the connecting ring 82 , and therefore that of the toothed wheel 72 . Alternatively, the connecting ring 82 can be welded to the second portion 70 of the rod 60 .
To facilitate the rotation of the connecting ring 82 and prevent the wear thereof as well as the wear of the external surface of the vent 52 , a metal washer 90 or a resilient material is interposed between the radially internal face of the connecting ring and the edge of the orifice of the vent 52 . The washer 90 also opposes the translation of the rod 60 radially inwardly with respect to the turbojet.
The device according to the invention works as follows: with the valve 40 initially in its closure position shown in FIG. 1 , it is simply necessary, in order to cause the opening of the orifice 20 and the entrance of cool air into the conduit 18 , to rotate the toothed wheel 72 in the direction of unscrewing of the threaded portion 58 of the rod 60 from the internal channel 56 of the ring 50 , owing to suitable drive means 76 .
In consideration of the locking in rotation of the ring 50 and the locking in translation of the rod 60 radially outwardly with respect to the turbojet, the rotation of the rod 60 in the direction of unscrewing of its threaded portion 58 drives a translation of the ring 50 toward the interior of the turbojet parallel to the axis 21 of the orifice 20 . The ring 50 drives with it the flapper 42 to which it is secured, until the downstream end of said flapper abuts against the radially external surface of the annular flange 38 .
In the opening position of the orifice 20 , the annular wall 34 ensures the guiding of the air toward the interior 16 of the conduit 18 .
The closing of the orifice 20 by the flapper 42 is performed by rotating the toothed wheel 72 in the direction of screwing of the threaded portion 58 of the rod 60 in the internal channel 56 of the ring 50 , until the seal 47 of the flapper is applied against the edge of the orifice 20 .
In a maneuver of the flapper 42 caused by the rotation of the toothed wheel 72 , the disengageable connecting ring 82 transmits the rotation of the toothed wheel 72 to the rod 60 .
When the flapper 42 reaches its closing position in contact with the edge of the orifice 20 or when it reaches its maximum opening position in which its downstream end abuts against the annular flange 38 , the ring 50 can no longer move in translation.
The connecting ring 82 then enables the rotation of the toothed wheel 72 to be decoupled from that of the rod 60 , if the toothed wheel 72 continues to be driven in rotation by the drive means 76 . Indeed, the locking in translation of the ring 50 prevents the rotation of the rod 60 and therefore of the connecting ring 82 , which is secured in rotation with said rod 60 . The force exerted by the rotational drive means 76 of the toothed wheel 72 is then converted into an axial force oriented radially outwardly by the respective teeth with oblique flanks 84 and 86 of the connecting ring and the toothed wheel, which force tends to move the toothed wheel 72 away from the connecting ring 82 while causing a compression of the resiliently deformable washers 88 .
The disengageable connecting ring 82 thus enables the risks of damage of the air bleed device 10 to be minimized if the toothed wheel 72 is driven beyond the limits of the course of the flapper 42 or the ring 50 , and thus prevents the need for sophisticated control means for controlling the drive means 76 of the toothed wheel 72 .
To prevent the flapper 42 or its lug 48 for connection to the ring 50 from being subjected to excessive mechanical stresses when the orifice is closed, and to prevent the rod 60 from being moved in translation radially inwardly with respect to the turbojet, causing compression of the resiliently deformable washers 88 by the nut 80 , in the closing position, it is preferable for the ring 50 to have an axial range such that, when the flapper is in the closing position, the open end of said ring abuts against the shoulder 64 of the internal surface of the vent 52 and/or against the collar 62 of the rod 60 , as in FIG. 1 . This also enables any clearance at the opening of the orifice to be prevented.
In addition, the external cross-section of the ring 50 and the internal cross-section of the vent 52 may be not square but rectangular, or more generally polygonal, so as to enable the ring 50 to be locked in rotation.
Alternatively, the ring 50 and the vent 52 can be cylindrical, and the locking in rotation of the ring 50 is in this case ensured by a rib/groove cooperation between the ring 50 and the vent 52 . For example, the internal surface of the vent 52 can comprise a rib extending according to the axis 54 of the vent and engaged in a groove with a conjugated shape formed on the external surface of the ring 50 in order to prevent the rotation of the latter.
FIG. 2 shows an overview of the cooling air bleed device 10 described above, and more specifically shows two valves 92 and 94 of this device and means for controlling these valves. The toothed wheel of each valve of the device is protected by a cylindrical fairing 96 comprising a rectilinear aperture 98 for the passage of a drive member, such as a flexible cable or a ball cable 100 in order to drive the toothed wheel. The cable 100 is actuated by a cylinder 102 mounted on the housing 12 of the nozzle and connected to an end 104 of the cable, with the other end 106 of said cable 100 being free at the outlet of the last valve 94 controlled by said cable.
The air bleed device 10 according to the invention provides the possibility of controlling all of the valves distributed around the nozzle in a synchronized manner by means of a single control actuator, in order to cool the controlled turbojet nozzle flaps, in which the control of this device can be performed manually by the airplane pilot.
The use of a flexible cable 100 in order to transmit the control movement of the actuator 102 to the toothed wheels 72 of the valves enables the system to withstand deformations of the housing 12 on which it is mounted while resisting the mechanical and thermal stresses generated by the flow of gases around said system.
In addition, such a cable 100 does not have to be in a closed circuit, and its end opposite the control cylinder 102 can remain free as already mentioned, thereby allowing for an advantageous weight gain. | An air bleed device for cooling components in a turbine engine, including an annular conduit having a substantially rectangular cross-section formed in a housing and having a radially internal wall swept by an airflow is disclosed. The device includes an air inlet orifice, and a flap valve for controlling the airflow entering through the orifice, formed by a plate borne by a maneuvering member mobile in translation parallel to the axis of the orifice between a position in which the plate closes off the orifice and a position in which the plate opens the orifice. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of U.S. patent application Ser. No. 14/298,036, filed Jun. 6, 2014, which is incorporated herein by reference in its entirety. The present application is also related to U.S. patent application Ser. No. 14/298,176 (published as U.S. Publication No. US 2015-0351627 A1) to Huth and Tran, “Fast Absolute-Reflectance Method for the Determination of Tear Film Lipid Layer Thickness,” filed Jun. 6, 2014, which is incorporated herein by reference in its entirety.
BACKGROUND
The present invention relates to methods for rapid calculation of tear film lipid and aqueous layer thickness and ocular surface refractive index from interferometry spectra.
While a method exists for calculation of parameters such as tear film lipid and aqueous layer thicknesses and ocular surface refractive index using interferometry spectra, this method is relatively slow, requiring many minutes to perform calculations using existing computing platforms. What is needed are improved methods which reduce calculation times using existing computing platforms.
SUMMARY
In one embodiment, the invention provides a method for determining optical properties of a corneal region. The method includes the steps of obtaining a combined tear film aqueous layer plus lipid layer thickness; obtaining a tear film lipid layer thickness; subtracting the tear film lipid layer thickness from the combined tear film aqueous layer plus lipid layer thickness to obtain a tear film aqueous layer thickness; and determining a corneal layer refractive index based on the tear film lipid layer thickness and the tear film aqueous layer thickness.
In another embodiment the invention provides a system for determining optical properties of a corneal region. The system includes a wavelength-dependent optical interferometer and a controller. The controller is in communication with the interferometer and is configured to obtain a combined tear film aqueous layer plus lipid layer thickness, obtain a tear film lipid layer thickness, subtract the tear film lipid layer thickness from the combined tear film aqueous layer plus lipid layer thickness to obtain a tear film aqueous layer thickness, and determine a corneal layer refractive index based on the tear film lipid layer thickness and the tear film aqueous layer thickness.
Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the results of the fitting procedure after using an initial thickness estimate of 3000 nm for the combined ‘aqueous+lipid’ layer thickness.
FIG. 2 shows results of a curve-fitting procedure using the presently-disclosed methods.
FIG. 3 shows results of a curve-fitting procedure with the same data as in FIG. 2 using the methods of the 557 patent.
FIG. 4 shows results of a curve-fitting procedure using the presently-disclosed methods.
FIG. 5 shows results of a curve-fitting procedure with the same data as in FIG. 4 using the methods of the '557 patent.
FIG. 6 shows results of a curve-fitting procedure using the presently-disclosed methods.
FIG. 7 shows results of a curve-fitting procedure with the same data as in FIG. 6 using the methods of the '557 patent.
FIG. 8 shows results of a curve-fitting procedure using the presently-disclosed methods.
FIG. 9 shows results of a curve-fitting procedure with the same data as in FIG. 8 using the methods of the '557 patent.
FIG. 10 shows results of a curve-fitting procedure using the presently-disclosed methods.
FIG. 11 shows results of a curve-fitting procedure with the same data as in FIG. 10 using the methods of the '557 patent.
FIG. 12 shows the correlation between the tear film lipid layer thickness values obtained using the tear film lipid layer thickness values using the methods from co-pending application Ser. No. 14/298,176 and those obtained using the presently-disclosed methods for the data from Examples 1-3.
FIG. 13 shows the correlation between the tear film aqueous layer thickness values obtained using the methods of the '293 patent with the methods from co-pending application Ser. No. 14/298,176 and those obtained using the present methods for the data from Examples 1-3.
FIG. 14 shows the results of a curve-fitting procedure using a second-order exponential c-term.
FIGS. 15 and 16 show spectra curve-fitted using a second-order ( FIG. 15 ) or first-order ( FIG. 16 ) exponential c-term.
FIG. 17 shows the correlation between tear film lipid layer thickness values obtained using the methods of the tear film lipid layer thickness values using the methods from co-pending application Ser. No. 14/298,176 and those obtained using the present methods for spectra from Example 4, with the exception of spectrum sub12#93.
FIG. 18 shows the correlation between tear film aqueous layer thickness values obtained using the methods of the '293 patent with the methods from co-pending application Ser. No. 14/298,176 and those obtained using the present methods for spectra from Example 4.
DETAILED DESCRIPTION
Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.
The methods disclosed herein offer a significant improvement over existing techniques, including those of the recently-issued patent method (Huth et al., U.S. Pat. No. 8,602,557, referred to herein as the '557 patent; incorporated herein by reference in its entirety). The '557 method takes as long as 475 seconds to complete all calculations for a single interferometry spectrum. This new method requires no more than a few seconds for the calculations, and thus considerably shortens calculation time and also allows one to utilize more interferometry spectra for data analysis, a critical need to provide more statistically robust data and to account for the effects of eye blink dynamics on these tear film parameters. This new method completes all calculations and provides identical results to the method of the '557 patent for lipid and aqueous layer thickness, surface refractive index, fitting error and b and c-terms in seconds (e.g., 10.9 sec. vs. 475 sec.; 3.6 sec. vs. 400 sec.; and 11.8 sec. vs. 408 sec.).
The new methods combine an existing method for ‘aqueous+lipid’ thickness (Huth et al. U.S. Pat. No. 7,959,293, referred to herein as the '293 patent, incorporated herein by reference in its entirety) with the co-pending method for fast lipid thickness (U.S. patent application Ser. No. 14/298,176), along with the methods in U.S. Pat. No. 8,602,557 for all measurements including lipid and aqueous layer thickness, surface refractive index, fitting error, and b and c-terms. The procedures of the '557 patent are modified by using ‘aqueous+lipid’ and lipid thickness inputs from the aforementioned fast methods, wherein the lipid thickness value is subtracted from the ‘aqueous+lipid’ thickness value to obtain an aqueous-only thickness value. As a result, the current calculation matrix of the '557 patent is reduced from a 6×7 matrix (6 aqueous layer thickness starting values and 7 lipid layer thickness starting values for the fitting algorithm) to a single matrix-fitting calculation, thereby reducing the time required for completing all calculations by a factor of approximately 1/(6×7)=1/42.
EXAMPLE 1
The first step in the method of the present invention uses the methods in Huth et al. U.S. Pat. No. 7,959,293, wherein interferometry spectra are produced and relative reflectance data are collected for a series of wavelengths, and wherein v2=relative reflectance and wherein v1=wavelength in nm, and the v1 and v2 data are fit to the following function using a Statistica (StatSoft®, Tulsa, Okla.) software program (Version 7.1, Series 1006b):
v 2= −a−b*v 1− c*v 1**2+ d* (1+( e/ 2* d )*cos((16.745* g/v 1)+ h ))*Exp(− J/v 1**2)
The Non-linear Estimation method within the Statistica software is used, wherein the equation for v2 above is input as the function to be estimated into the space provided in the user specified regression, least squares module. The Statistica software program uses the Levenburg-Marquardt algorithm to achieve a minimum in the sum of squares of the differences between the interferometer-measured spectrum and a fitted spectrum, fit to the function above, wherein the variables a, b, c, d, e, g, h, and J are iteratively changed. Other mathematical algorithms for fitting data are available within Statistica and other software platforms and can also be employed. This software module requires the number of calculation/fitting iterations to be selected. In one embodiment, 50-300 iterations were found to be acceptable, although in various other embodiments other lower or higher numbers of iterations are also acceptable and can be easily determined by an evaluation of the fit. The program also requires starting values for the variable terms, i.e. a, b, c, d, e, g, h, and J, where the g-term is the initial estimate of the tear film ‘aqueous+lipid’ layer thickness.
The spectrum in this example was taken from a human subject who was not wearing contact lenses, with the identification number sub21#43. FIG. 1 shows the results of the fitting procedure after using an initial thickness estimate of 3000 nm for the combined ‘aqueous+lipid’ layer thickness. A result of 2942.7 nm total thickness for the combined ‘aqueous+lipid’ layer thickness was obtained.
The next step in the method is to calculate the tear film lipid layer thickness. This is calculated using the methods described in co-pending application 14/298,176, using input values for the a-term of 65 nm and for the b-term of 0.66, and the following equation:
v 6=((1−((8* v 1* v 2**2* v 3)/(( v 1**2+ v 2**2)*( V 2**2+ v 3**2)+4* v 1 *v 2**2* v 3+(( v 1**2 −v 2**2)*( v 2**2− v 3**2)*(cos(4*3.14159* v 2* a* 0.98666/ v 4)))))))* b/v 5
where the input data are v6=R(λ) meas tear lipid sample (measured % relative reflectance) and wherein v1=n 0 air=1, v2=n 1 (λ) tear film lipid (Sellmeier-form), v3=n 2 (λ) aqueous, v4=measured λ and v5=R(λ) absolute BK7 reference (BK7 absolute R calc)/100 and wherein a Levenberg-Marquardt algorithm is used for fitting the data. The results obtained are shown in Table 1.
TABLE 1
Level of confidence: 95.0% (alpha = 0.050)
Estimate
Standard
t-value
p-level
Lo. Conf
Up. Conf
a
31.77767
0.130980
242.6155
0.00
31.52055
32.03480
b
0.37007
0.000584
633.6999
0.00
0.36892
0.37122
a
31.77767
0.130980
242.6155
0.00
31.52055
32.03480
b
0.37007
0.000584
633.6999
0.00
0.36892
0.37122
The value obtained for the a-term, the tear film lipid layer thickness, is 31.78 nm. The calculation of the tear film lipid layer thickness can also be completed in a parallel computer-processing step along with the calculation of the combined ‘aqueous+lipid’ layer thickness.
Taking the thickness value for the combined ‘aqueous+lipid’ layer thickness of 2942.7 nm from the first step, the tear film lipid layer-only thickness of 31.78 nm is subtracted and the aqueous-only thickness of 2910.92 nm is obtained. These values for aqueous layer-only thickness and lipid layer-only thickness are input as starting values into the following modified Matlab software program (MATLAB R2013a), taken from U.S. Pat. No. 8,602,557, incorporated herein in its entirety by reference, and modified where indicated.
% Program for eye reflectance - Statistica inputs (no variable aqueous or
lipid layer thicknesses) for one spectrum %
% Remarks: b_parameter starting value:1, epithelium refractive index
starting value:1.338+0.00306.*(1000./L).{circumflex over ( )}2
%--------------------------------------------------------------------------------------
-----------------------------------%
% Aqueous layer thickness from Statistica
At=2910.92% Excel read
excl=xlsread(‘sub21#43.xls’);
% ----------------j1_25min_--------------------------------------------------------
---------------------------------------------%
% Parameters
At=At; (′557 program line: At=At−50)
z2=0;
% Plot of exp. data
plot(excl(:,1),excl(:,2))
L=[excl(:,1)];
R=[excl(:,2)];
hold on
% Loops
for y=0 (′557 program line: y = 0:20:100)
z2=z2+1;
z=0;
% Input lipid thickness from Statistica (no semi-colon or punctuation at
% end)
for p=31.78 (′557 program line: p = 20:20:140)
The remaining program code is identical to that in U.S. Pat. No. 8,602,557.
The following results were obtained in 7.8 seconds with an IBM ThinkPad computer with an Intel® Core™ 2 Duo CPU, T9400@2.53 GHz (1.59 GHz, 1.98 GB of RAM):
Lipid layer thickness: 35.1 nm
Aqueous layer thickness: 2969.5 nm
Corneal surface refractive index: 1.3360
b-term: 0.3760
c-term: 0.0560
error: 2.96e−6
FIG. 2 shows the fit of the results (smooth line) to the original spectrum (jagged line), based on data from subject sub21#43. The parameter results were identical to those obtained with the program code in U.S. Pat. No. 8,602,557, which took 131 seconds to run on the same computer with the same data set (i.e. from subject sub21#43). The fit obtained in FIG. 2 with the method of the present invention is substantially the same as that obtained with the method in U.S. Pat. No. 8,602,557 ( FIG. 3 ).
EXAMPLE 2
The method of Example 1 was followed with analysis of an interferometry spectrum taken from a human subject, identification number RH1f8hr#20, wearing Acuvue 2® soft contact lenses.
The Statistica results were 1572.15 nm for the combined tear film ‘aqueous+lipid’ layer thickness and 31.53 nm for the tear film lipid layer thickness, giving 1540.60 nm for the tear film aqueous layer thickness. As with Example 1, in the present Example 2 the tear film aqueous and lipid layer thickness values were input as starting values into the revised Matlab software program. The substrate surface underlying the tear film in this case was the contact lens surface, rather than the corneal epithelium as in Example 1. Thus, the surface refractive index starting value for the Matlab software program was the published value for the bulk contact lens, 1.4055. It was determined, however, that using refractive index starting values of 1.338, 1.37, 1.4055, and 1.42 all gave identical results. Thus, the nominal refractive index starting value for the corneal epithelium, 1.338, can also be used for tear film spectra from contact lens wearers. Table 2 lists the following results, which were obtained in 3.1 seconds with the method of the present invention, compared to 467 seconds with the method in the '557 patent.
TABLE 2
Parameter
present invention
′557 method
Lipid layer thickness, nm
56.5
63.5
Aqueous layer thickness, nm
1507.6
1502.0
Lens surface refractive index
1.3649
1.3663
b-term
0.0297
0.0268
c-term
0.3940
0.3858
Error
1.02E−07
9.81E−08
Calculation time, seconds
3
467
Lipid layer thickness, nm
56.5
63.5
Aqueous layer thickness, nm
1507.6
1502.0
Lens surface refractive index
1.3649
1.3663
b-term
0.0297
0.0268
c-term
0.3940
0.3858
Error
1.02E−07
9.81E−08
Calculation time, seconds
3
467
The results above and fit obtained in FIG. 4 with the method of the present invention are very close to that obtained with the slower methods of U.S. Pat. No. 8,602,557 ( FIG. 5 ) using the same data set (both of FIGS. 4 and 5 use data from subject RH1f8hr#20).
EXAMPLE 3
The method of Example 1 was followed with interferometry spectra taken from six additional subjects, none of whom was wearing contact lenses. Results are shown in Table 3. Interferometry spectra from four subjects, with identification numbers sub1#29, sub4#5, sub6#7, and sub6base#84 produced the same results for the method of the present invention as with the methods of the '557 patent. Calculation times for all four spectra were much shorter with the method of the present invention, ranging from 2.2-11.8 sec, compared to 137-408 sec for the methods of the '557 patent. Note in Table 3 that the methods of the '557 patent consistently produced longer calculation times than the method of the present invention, although different times on occasion when the calculations were repeated. It was noted that the program tended to run faster after the first calculation for the particular day.
FIGS. 6 and 7 show analyses of data for subject sub4#5 using the methods of the present invention and of the '557 patent, respectively. The fits and results are essentially identical, but the calculation times are 3.8 vs. 235 seconds, respectively. The remaining three subjects and four spectra, with identification numbers sub2DE, sub3#15, sub3#56, and sub12#93, produced close results for the method of the present invention compared to the methods of the '557 patent.
FIGS. 8 and 9 show spectrum sub2DE analyses with the method of the present invention and the methods of the '557 patent, respectively. The very low tear film aqueous layer reflectance interference oscillation amplitude in this spectrum makes the analysis challenging, which required 400 seconds with the methods of the '557 patent, whereas the present methods achieved a fit in only 3.8 seconds.
FIGS. 10 and 11 show spectrum sub3#56 analyses with the method of the present invention and the methods of the '557 patent, respectively. Table 3 shows that the original tear film lipid layer thicknesses derived from the Statistica program, which are used as input values for the present Matlab software program, are close, but different from the resulting Matlab program calculated thicknesses derived from the spectrum fits. Table 3 also shows that the present method produced closer lipid layer thickness values to those obtained from the Statistica program in those cases in which results between the methods of the '557 patent and the present methods differ.
FIG. 12 shows the correlation between the tear film lipid layer thickness values obtained using the tear film lipid layer thickness values using the methods from co-pending application Ser. No. 14/298,176 and those obtained using the presently-disclosed Matlab method lipid layer thickness values for spectra from Examples 1-3. A reasonably good correlation was found (slope=0.9961, intercept 13.267 nm and r^2=0.9051) given the nanometer measurement scale for the clinical interferometer and associated mathematics and software. The average difference found was 13 nm, which is considered good. Differences are expected due to the more rigorous calculations required for the Matlab software program, which calculates tear film aqueous and lipid layer thicknesses and either corneal surface or contact lens surface refractive indices. It can be seen from Table 3 that the differences become small as the tear film aqueous layer thickness increases, likely due to the better spectrum fits which can be obtained with additional aqueous layer thickness reflectance interference oscillations.
FIG. 13 shows the correlation between the tear film aqueous layer thickness values obtained using the methods of the '293 patent with the methods from co-pending application Ser. No. 14/298,176 and those obtained using the present Matlab method aqueous layer thickness values for spectra from Examples 1-3. A very good correlation was found (slope=0.9998, intercept 8.8298 nm and r^2=0.9981).
TABLE 3
Spectrum
Stat aq/lip inputs/match
Calc. time, sec
Stat aq nm
Stat lip nm
Stat ap + lip
Stat b
sub1#29
3453.51/24.19/same
11.8
3453.51
24.19
3477.70
0.8265
sub4#5
1956.79/24.83/same
3.8
1956.79
24.83
1981.62
0.6836
sub6#7
3845.97/67.07/same
2.2
3845.97
67.07
3913.04
0.6762
sub6base#84
3204/80/same
2.4
3204.24
80.32
3284.56
0.2876
sub2DE
original ′557 method
400
sub2DE
2542.95/79.67/close values
3.0
2542.95
79.67
2622.62
1.0323
sub3#15
original ′557 method
206
sub3#15
1555.7/41.84/close values
2.0
1555.70
41.84
1597.54
1.0761
sub3#56
original ′557 method
361
sub3#56
1386.26/42.00/close values
2.8
1386.26
42.00
1428.26
1.2879
sub12#93
orignial ′557 method
475
sub12#93
4092.98/30.66/close values
21.9
4092.98
30.66
4123.64
1.2512
Mlab lip nm
Mlab b
Mlab c
Mlab aq nm
Mlab nd
Mlab error
567 Mlab calc time, sec
34.7
0.9223
0.1958
3405.6
1.3328
8.17E−06
408; 402
37.0
0.7530
0.1850
1991.4
1.3382
2.40E−05
235
71.3
0.6526
0.0204
3870.1
1.1351
1.53E−05
137
93.5
0.2227
−0.1119
3217.2
1.3369
1.83E−05
220; 156
108.6
0.6040
−0.2663
2595.4
1.1348
2.11E−05
400
95.6
0.8629
−0.0593
2457.3
1.3313
2.32E−05
71.3
1.0142
0.2230
1546.4
1.3368
2.67E−05
206
64.4
1.1702
0.2650
1553.0
1.3366
2.89E−05
64.5
1.2768
0.2084
1365.9
1.3225
1.87E−05
361
58.1
1.4258
0.2269
1371.7
1.3296
1.87E−05
39.4
1.3000
0.1199
3883.3
1.3298
1.62E−05
475
38.3
1.3487
0.1345
4053.0
1.3341
1.69E−05
Spectrum
Stat aq/lip inputs/match
Calc. time, sec
Stat aq nm
Stat lip nm
Stat aq + lip
Stat b
sub1#29
3453.51/24.19/same
11.8
3453.51
24.19
3477.70
0.8265
sub4#5
1956.79/24.83/same
3.8
1956.79
24.83
1981.62
0.6836
sub6#7
3845.97/67.07/same
2.2
3845.97
67.07
3913.04
0.6762
sub6base#84
3204/80/same
2.4
3204.24
80.32
3284.56
0.2876
sub2DE
original ′557 method
400
sub2DE
2542.95/79.67/close values
3.0
2542.95
79.67
2622.62
1.0323
sub3#15
original ′557 method
206
sub3#15
1555.7/41.84/close values
2.0
1555.70
41.84
1597.54
1.0761
sub3#56
original ′557 method
361
sub3#56
1386.26/42.00/close values
2.8
1386.26
42.00
1428.26
1.2879
sub12#93
original ′557 method
475
sub12#93
4092.98/30.66/close values
21.9
4092.98
30.66
4123.64
1.2512
Mlab lip nm
Mlab b
Mlab c
Mlab aq nm
Mlab nd
Mlab error
567 Mlab calc time, sec
34.7
0.9223
0.1958
3405.6
1.3328
8.17E−06
408; 402
37.0
0.7530
0.1850
1991.4
1.3382
2.40E−05
235
71.3
0.6526
0.0204
3870.1
1.3351
1.53E−05
137
93.5
0.2227
−0.1119
3217.2
1.3369
1.83E−05
220; 156
108.6
0.6040
−0.2663
2595.4
1.3348
2.11E−05
400
95.6
0.8629
−0.0593
2457.3
1.3313
2.32E−05
71.3
1.0142
0.2230
1546.4
1.3368
2.67E−05
206
64.4
1.1702
0.2650
1553.0
1.3366
2.89E−05
64.5
1.2768
0.2084
1365.9
1.3295
1.87E−05
361
58.1
1.4258
0.2269
1371.7
1.3296
1.87E−05
39.4
1.3000
0.1199
3883.3
1.3298
1.62E−05
475
38.3
1.3487
0.1345
4053.0
1.3341
1.69E−05
EXAMPLE 4
In one embodiment, the method of Example 1 was followed using the same interferometry spectra as shown in Table 3. A faster computer was used for the spectrum fits in this example, an Intel® Core™ i5-4300U CPU@1.90, 2.50 GHz with 4.00 GB RAM and a 64-bit operating system. In this embodiment the exponential term for the c-term multiplier of the Matlab program was changed from a first-order exponential to a second-order exponential (results shown in Table 4):
From * exp(−b(5).*(1000./L).^1.0)) in the new program herein for the mathematical function to *exp(−b(5).*(1000./L).^2.0)) (Note that this change is made on three program lines).
TABLE 4
Spectrum
Stat aq/lip inputs/match
Calc. time, sec
Stat aq nm
Stat lip nm
Stat aq + lip
Stat b
RHIf8hr#20
1540.6/31.53/close values
2.4
1540.62
31.53
1572.15
0.0238
sub3#15
1555.7/41.84/close values
2.5
1555.70
41.84
1597.54
1.0761
sub2DE
2542.95/79.67/close values
3.1
2542.95
79.67
2622.62
1.0323
sub3#56
1386.26/42.00/close values
1.8
1386.26
42.00
1428.26
1.2879
sub6base#84
3204/80/close values
1.9
3204.24
80.32
3284.56
0.2876
sub4#5
1956.79/24.83/close values
3.5
1956.79
24.83
1981.62
0.6836
sub1#29
3453.51/24.19/close values
3.7
3453.51
24.19
3477.70
0.8265
sub21#43
2910.92/31.78/same
7.8
2910.92
31.78
2942.70
0.3701
sub6#7
3845.97/67.07/same
2.2
3845.97
67.07
3913.04
0.6762
sub12#93*
4092.98/30.66/close values
3.2
4092.98
30.66
4123.64
1.2512
sub12#93**
4092.98/30.66/close values
3.4
4092.98
30.66
4123.64
1.2512
Mlab lip nm
Mlab b
Mlab c
Mlab aq nm
Mlab nd
Mlab error
47.0
0.0241
0.1146
1518.2
1.3630
1.09E−07
56.3
1.0413
0.0823
1561.9
1.3364
2.90E−05
99.4
0.8619
−0.0336
2601.2
1.3348
2.11E−05
50.8
1.2829
0.0633
1379.9
1.3298
1.88E−05
84.2
0.2844
0.0059
3222.2
1.3367
1.91E−05
17.8
0.6834
−0.0288
2014.1
1.3377
2.74E−05
14.5
0.8188
−0.0301
3429.6
1.3329
9.20E−06
16.1
0.3684
−0.0773
2990.3
1.3357
2.88E−06
62.2
0.7345
0.0196
3874.9
1.3350
1.61E−05
19.3
1.2421
−0.058
6131.5
1.3316
4.00E−06
38.4
1.3505
0.1369
3879.5
1.3298
1.61E−05
Spectrum
Stat aq/lip inputs/match
Calc. time, sec
Stat aq nm
Stat lip nm
Stat aq + lip
Stat b
RHIf8hr#20
1540.6/31.53/close values
2.4
1540.62
31.53
1572.15
0.0238
sub3#15
1555.7/41.84/close values
2.5
1555.70
41.84
1597.54
1.0761
sub2DE
2542.95/79.67/close values
3.1
2542.95
79.67
2622.62
1.0323
sub3#56
1386.26/42.00/close values
1.8
1386.26
42.00
1428.26
1.2879
sub6base#84
3204/80/close values
1.9
3204.24
80.32
3284.56
0.2876
sub4#5
1956.79/24.83/close values
3.5
1956.79
24.83
1981.62
0.6836
sub1#29
3453.51/24.19/close values
3.7
3453.51
24.19
3477.70
0.8265
sub21#43
2910.92/31.78/same
7.8
2910.92
31.78
2942.70
0.3701
sub6#7
3845.97/67.07/same
2.2
3845.97
67.07
3913.04
0.6762
sub12#93*
4092.98/30.66/close values
3.2
4092.98
30.66
4123.64
1.2512
sub12#93**
4092.98/30.66/close values
3.4
4092.98
30.66
4123.64
1.2512
Mlab lip nm
Mlab b
Mlab c
Mlab aq nm
Mlab nd
Mlab error
47.0
0.0241
0.1146
1518.2
1.3630
1.09E−07
56.3
1.0413
0.0823
1561.9
1.3364
2.90E−05
99.4
0.8619
−0.0336
2601.2
1.3348
2.11E−05
50.8
1.2829
0.0633
1379.9
1.3298
1.88E−05
84.2
0.2844
0.005
3222.2
1.3367
1.91E−05
17.8
0.6834
−0.0288
2014.1
1.3377
2.74E−05
14.5
0.8188
−0.0301
3429.6
1.3329
9.20E−06
16.1
0.3684
−0.0773
2990.3
1.3357
2.88E−06
62.2
0.7345
0.0196
3874.9
1.3350
1.61E−05
19.3
1.2421
−0.058
6131.5
1.3316
4.00E−06
38.4
1.3505
0.1369
3879.5
1.3298
1.61E−05
*poor fit;
**good fit with exp{circumflex over ( )}1 for c-term
It can be seen in Table 4 that, with the exception of a single spectrum, sub12#93, values close to those obtained in Table 3 were produced. FIG. 14 shows the results of the fit obtained for spectrum RHlf8hr#20 as an example for the usage of the second-order exponential c-term.
The present method Matlab program with a second-order exponential for the c-term achieved good fits for all other spectra in Table 4 (data not shown), with the exception of spectrum sub12#93. This is seen in comparing FIG. 15 , showing the second order exponential c-term result, with FIG. 16 , showing the first-order exponential c-term result. Thus, the second-order exponential c-term can be used as well as the first-order exponential c-term, with some exceptions.
FIG. 17 shows the correlation between tear film lipid layer thickness values obtained using the methods of the tear film lipid layer thickness values using the methods from co-pending application Ser. No. 14/298,176 and those obtained using the present Matlab method lipid layer thickness values for spectra from Example 4, with the exception of spectrum sub12#93. A reasonably good correlation was again found (slope=1.2268, intercept 7.8782 nm and r^2=0.8536) given the nanometer measurement scale for the clinical interferometer and associated mathematics and software. The average difference found for the data set was 2.8 nm, as some Statistica values were higher and some were lower than the Matlab-fitted values for the same spectra.
FIG. 18 shows the correlation between tear film aqueous layer thickness values obtained using the methods of the '293 patent with the methods from co-pending application Ser. No. 14/298,176 and those obtained using the present Matlab method aqueous layer thickness values for spectra from Example 4. A very good correlation was found (slope=1.0086, intercept 0.3617 nm and r^2=0.9985).
The method of the present invention also includes methods wherein only one of the tear film aqueous or lipid layer thickness values derived from the Statistica program are used as input starting values, and the Matlab software is allowed to run the other 7× matrix calculations for lipid layer thickness (when aqueous thickness is input) or the 6× matrix calculations for aqueous layer thickness (when lipid thickness is input). Both of these alternative methods result in significantly improved shorter Matlab software program calculation times due to the reduced sizes of the calculation matrices.
In various embodiments, the disclosed methods may be carried out on a computing system in communication with an interferometer (e.g. a wavelength-dependent interferometer). The computing system may include one or more computer systems in communication with one another through various wired and wireless communication means which may include communications through the Internet and/or a local network (LAN). Each computer system may include an input device, an output device, a storage medium (including non-transient computer-readable media), and a processor such as a microprocessor. Possible input devices include a keyboard, a computer mouse, a touch screen, and the like. Output devices include a cathode-ray tube (CRT) computer monitor, a LCD or LED computer monitor, and the like. Storage media may include various types of memory such as a hard disk, RAM, flash memory, and other magnetic, optical, physical, or electronic memory devices. The processor may be any suitable computer processor for performing calculations and directing other functions for performing input, output, calculation, and display of data in the disclosed system. Implementation of the computing system may include generating a set of instructions and data that are stored on one or more of the storage media and operated on by a controller. Thus, one or more controllers may be programmed to carry out embodiments of the disclosed invention. The data associated with the system may include image data, numerical data, or other types of data.
Various features and advantages of the invention are set forth in the following claims. | A method for determining optical properties of a corneal region. The method includes the steps of obtaining a combined tear film aqueous layer plus lipid layer thickness; obtaining a tear film lipid layer thickness; subtracting the tear film lipid layer thickness from the combined tear film aqueous layer plus lipid layer thickness to obtain a tear film aqueous layer thickness; and determining a corneal layer refractive index based on the tear film lipid layer thickness and the tear film aqueous layer thickness. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
Locatelli et al copending application, Ser. No. 296,212 filed concurrently herewith, and assigned to the assignee hereof.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to novel supported sequestering agents, with "supported sequestering agent" being defined as an agent capable of combining with various cations to form a complex therewith, said agent being covalently tethered to a support substrate.
The present invention also relates to the preparation of such novel sequestering agents, and to the use thereof in organic synthesis and for the extraction of various metals.
2. Description of the Prior Art
Known to this general art [compare Angew. Chem. Int., English Edition, 18, 421-429 (1979)], are polystyrene resins bearing quaternary ammonium groups having the structural formula: ##STR2## wherein R 1 , R 2 and R 3 are essentially alkyl radicals, and ##STR3## is the polystyrene backbone.
The principal disadvantage which limits the use of such resins on an industrial scale is, most notably, their lack of stability at temperatures in excess of about 100° C.
In the aforenoted reference, there are also described certain "crown ethers" and "cryptants" grafted onto polystyrene backbones, the same being prepared by the reaction of appropriate amine derivative, the crown ether or the cryptant, with a chloromethyl polystyrene.
These substituted polymers, for example, those of the structural formulae: ##STR4## are much more useful than the aforesaid ammonium salts borne by polystyrene backbones by virtue of their greater activity and their better thermal stability. Nevertheless, there remain a certain number of disadvantages which do not favor their utilization on an industrial scale. Indeed, the crown ethers and cryptants are themselves compounds having highly sophisticated and complex molecular structures. It thus follows that the processes for the preparation thereof and their actual utilization are quite critical. Furthermore, their cost of production is extremely high. And these same disadvantages are multiplied on the level of the more complex macromolecules obtained after grafting same onto a polystyrene backbone.
The three types of products noted hereinabove have been tested in the prior art in nucleophilic substitution reactions by liquid/liquid phase transfer catalysis, such as in the halogen exchange reaction of bromooctane to 1-iodooctane and in nucleophilic substitution reactions by liquid/liquid phase transfer catalysis, such as, for example, in the reaction of benzyl chloride with alkaline acetates to yield benzyl acetate [Pure and Appln. Chem., 51, pp 2313-2330 (1979)].
Thus, serious need exists in this art for a novel class of sequestering agents which avoids those disadvantages and drawbacks above outlined.
SUMMARY OF THE INVENTION
Accordingly, a major object of the present invention is the provision of an improved class of sequestering agents, the same comprising a cross-linked organic polymeric substrate, said substrate having covalently tethered thereto a plurality of functional groups having the structural formula: ##STR5## wherein R 1 , R 2 , R 3 , R 4 , R 6 and R 7 , which are identical or different, each represents a hydrogen atom or an alkyl radical having 1 to 4 carbon atoms, R 5 and R 8 , which are also identical or different, each represents a hydrogen atom, an alkyl or cycloalkyl radical having 1 to 12 carbon atoms, a phenyl radical, a --C q H 2q --φ or C q H 2+1 --φ-- radical with q greater than or equal to 1 and smaller than or equal to approximately 12, and wherein n, m and p, also identical or different, are greater than or equal to 1 and smaller than or equal to 10, and φ is phenyl.
DETAILED DESCRIPTION OF THE INVENTION
More particularly according to this invention, R 1 , R 2 , R 3 , R 4 , R 6 and R 7 , which may be identical or different, preferably represent a hydrogen atom or a methyl radical, and R 5 and R 8 which may also be identical or different, each preferably represents a hydrogen atom or an alkyl radical having 1 to 4 carbon atoms. According to another preferred embodiment of the invention, n, m and p, also identical or different, are greater than or equal to 1 and less than or equal to 6.
The moieties of the following structural formulae are exemplary of functional groups consistent with the present invention: ##STR6##
The support substrate is advantageously derived from a cross-linked organic polymer containing groups that may be facilely substituted with the functional groups of Formula I.
Exemplary of organic polymers suitable as backbone substrates according to the present invention are polymers derived from vinyl-aromatic compounds, such as styrene, methylstyrene and the copolymers of vinyl-aromatic compounds and C 4 -C 6 conjugated dienes, such as the copolymers of styrene and butadiene and of styrene and isoprene.
Polystyrene is the preferred organic polymer, and, in which case, the preferred cross-linking agent is divinylbenzene. The degree of cross-linking too is an important factor. In particular, it is of course necessary that the functional groups of Formula 1 which are grafted onto the polystyrene backbone be active. For this, it is necessary that the molecules of the solvent with which the supported sequestering agent is to be employed, be capable of penetrating into the polymer. For this reason, it is required that the degree of cross-linking not be excessively high such that the penetration of the solvent and the reagents will not be hindered. It is preferred to employ a polystyrene wherein the amount of cross-linking by the divinylbenzene does not exceed about 10%. Even more preferred is a cross-linking degree of less than approximately 5%.
Preferred groups on the polystyrene adapted for substitution are chlorine or bromine, or the chloro- or bromomethyl radical, --CH 2 Cl or --CH 2 Br, attached to the benzene nucleus of the polystyrene.
In another preferred embodiment of the invention, the percentage of the benzene rings of the polystyrene bearing a functional group is higher than 10%.
The preferred supported sequestering agents are those of the following structural formulae: ##STR7## derived from chloro- or bromomethyl polystyrene, cross-linked with divinylbenzene and having the formula: ##STR8## wherein X represents Cl or Br.
The present invention also relates to a process for the preparation of the sequestering agents defined hereinabove. The process according to the invention is characterized in that a compound of the formula: ##STR9## wherein A represents an alkali metal and R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , n, m and p are as defined above, is reacted with a cross-linked organic polymer containing the aforesaid groups adapted for substitution, at a temperature ranging from about 20° to 150° C., in an aprotic solvent.
In a preferred process embodiment of the invention, A represents sodium or potassium.
According to yet another preferred embodiment of the invention, the solvent is advantageously selected from the group comprising benzene, toluene, N-methylpyrrolidone, hexamethylphosphorotriamide, dioxane, tetrahydrofuran, dimethoxyethane and sulfolane.
In another preferred embodiment of the invention, a chloro- or bromomethyl polystyrene having a degree of cross-linking with divinylbenzene of less than 10% and having a proportion of chlorine or bromine between approximately 0.5 and approximately 7 milliequivalents of chlorine or bromine/g, is reacted with the compound of Formula [II].
The supported sequestering agents according to the invention form complexes with the ammonium cation NH 4 + and its derivatives and the cations derived from metals of Groups I A , II A , III A , IV A , V A , VI A , VII A , VIII, I B , II B , III B , IV B and V B of the Periodic Table.
More particularly, the supported sequestering agents according to the invention form complexes with:
(i) NH 4 + and the derivatives RNH 3 + wherein R is an alkyl radical or an aryl radical; and
(ii) the cations derived from the metals:
Li, Na, K, Rb, Co,
Mg, Ca, Sr, Ba,
Sc, Y, La and lanthanides, Ac and actinides,
Ti, Zr, Hj,
V, Nb, Ta,
Cr, Nb, Ta,
Mn, Tc, Re,
Fe, Co, Ni,
Ru, Rh, Rd,
Os, Ir, Pt,
Cu, Ag, Au,
Zn, Cd, Hg,
Al, Ga, In, Tl,
Ge, Sn, Pb,
Sb, Bi.
The invention also relates to the use of the subject sequestering agents in organic synthesis. In effect, the supported sequestering agents according to the invention enable the reaction, in suitable solvent, of an ionic organic or inorganic reagent typically insoluble in such solvent, with a substrate soluble in said solvent, with the sequestering agents added to the reaction medium enabling intimate contact, in the medium, of the reagent and the substrate.
As mentioned hereinabove, even though the support may be insoluble in the solvent, the latter may penetrate the cross-linked polymer and transport the ionic reagent to the functional groups of Formula I grafted onto the support. The functional groups then complex the cation of the ionic reagent, whereupon the complexed entity may be considered as being in solution in the solvent wherein the substrate is soluble.
The immediately aforesaid, thus, permits the reaction to take place.
These anionic, organic or inorganic reagents have the general formula M + Y - , wherein M + represents one of the aforenoted cations and Y - represents an organic or inorganic anion. Exemplary of inorganic anions are CN - , SCN - , F - , Bn - , l - and exemplary of organic anions are the phenates, alcoholates, thioalcoholates, thiophenates, silanolates and carboxylates.
As examples of syntheses that may be effected with the supported sequestering agents according to the invention, syntheses employing nucleophilic substitution reactions, such as, for example, the substitution of a halogen on an aliphatic or aromatic substrate by a Y - group, such as defined hereinabove, are representative.
The advantages to be obtained from the application of the supported sequestering agents according to the invention reside primarily in their ease of separation from the reaction medium upon completion of the reaction. This separation may be effected by simple decantation or filtration. Secondly, the high possible rate of recycling of the sequestering agent must be emphasized; this improves the economy of the process.
The invention also relates to the use of the subject sequestering agents in the extraction of metals by the same mechanism enunciated in the case of organic synthesis. It is in effect possible to extract organic or inorganic salts from an aqueous solution by the simple contact of such solution with at least one supported sequestering agent according to the invention, optionally impregnated with a solvent, such that the latter, as mentioned hereinabove, activates the functional groups of Formula I, if this is required.
As an example of this phenomenon, the extraction of sodium picrate from an aqueous solution thereof is representative.
The advantages deriving from the employment of the sequestering agents according to the invention for the extraction of metals are principally found by reason of the fact that there ensues no contamination by the supported sequestering agents of the aqueous phase from which the metallic salts are extracted. On the other hand, the recycling rate possible after regeneration of the sequestering agent enhances the economy of the process.
The compounds having the structural formula: ##STR10## may be prepared by reaction of an alkali metal, in metallic state, in an organic solvent medium (toluene, tetrahydrofuran, dioxane, for example) at a temperature between approximately 20° and 90° C. for 4 to 6 h, with an amino alcohol: ##STR11## itself prepared by the reaction of a polyalkylene glycol having the structural formula:
HO--(CHR.sub.1 --CHR.sub.2 O).sub.n H
wherein R 1 , R 2 and n are as above defined, with a bis(polyoxaalkyl) amine having the formula: ##STR12## wherein R 3 to R 8 and m and p also are as above defined, the molar ratio of the polyalkylene glycol to the bis(polyoxaalkyl)amine being at least 1.5, in the presence of a hydrogenation/dehydrogenation catalyst at a temperature between 120° C. and 220° C., preferably between 150° C. and 200° C.
Exemplary of the catalyst, nickel catalysts of the Raney or Harshaw nickel type are representative, the amount of the catalyst being between 1 and 15% by weight (preferably between 2 and 6%).
The molar ratio of the polyalkylene glycol to the bis(polyoxaalkyl)amine is preferably between 1.5 times and 10 times the stoichiometric amount (even more preferably between 2 and 6 times the stoichiometric amount). The reaction is preferably effected in the presence of hydrogen (1 to 10% by weight of hydrogen is used with respect to the polyalkylene glycol employed) under atmospheric pressure.
In order to further illustrate the present invention and the advantages thereof, the following specific examples are given, it being understood that same are intended only as illustrative and in nowise limitative.
EXAMPLE 1
Into a three-necked, 250 ml reactor, equipped with a magnetic stirrer, a reflux condenser and a nitrogen inlet, the following materials were successively introduced: 100 cm 3 anhydrous toluene, 13 g N-(8'-hydroxy-3',6'-dioxaoctyl)-11-aza-2,5,8,14,17,20-hexaoxaheneicosane (prepared as outlined hereinbelow), and 0.69 g metallic sodium. After 6 hours at 60° C. under agitation, the sodium had completely disappeared. Subsequently, 14.8 g polystyrene, cross-linked with 2% divinylbenzene, were introduced; same contained 1.35×10 -3 chloromethyl groups per gram of polymer, to be noted as 1.35 meg of chlorine/g. The mixture was heated to 60° C. for 48 hours under a nitrogen atmosphere. After cooling, the polymer was filtered and washed with water (to eliminate salts) and then with methanol.
The product was then dried under a vacuum at 50° C.
In this fashion, 20 g of an aminoether grafted onto the polystyrene were obtained, the structural formula of which was as follows: ##STR13##
The degree of grafting was 77%.
Preparation of N-(8'-hydroxy-3',6'-dioxaoctyl)-11-aza-2,5,8,14 17,20-Hexaoxaheneicosane: ##STR14##
Into a 2 liter, three-necked flask, equipped with stirring means, a hydrogen inlet, a column and a condenser to collect the water, the following materials were charged:
______________________________________(i) 11-Aza-2,5,8,14,17,20-hexaoxa- 250 g (0.80 mole) heneicosane(ii) Triethylene glycol 550 g (3.66 mole)(iii) Raney nickel (dehydrated) 50 g______________________________________
After 5 hours of reaction at 180° under a stream of hydrogen (1 liter/min) the Raney nickel was filtered and the filtrate was evaporated to 300° under 0.1 mmHg (13.3 Pa).
325 g of the desired aminoalcohol were obtained, representing a yield of 92.2%.
EXAMPLE 2
Following the procedure and under the conditions outlined in Example 1, the following materials were introduced: 100 cm 3 toluene, 14.3 g N-(8'-hydroxy-3',6'-dioxaoctyl)-9-aza-3,6,12,15-tetraoxaheptadecane prepared in a fashion similar to that described hereinabove, and 0.69 g metallic sodium. After 6 hours at 60° C., 5 g polystyrene cross-linked with 8% divinylbenzene and containing 4 meq/g of chlorine, were added. Heating was continued for 20 hours, followed by cooling and filtering of the mixture.
The precipitate was washed with water and then with methanol.
After drying at 50° C. under vacuum, 9.2 g of graft polymer were obtained, having the structural formula: ##STR15##
The degree of grafting was 65%.
EXAMPLE 3
Following the procedure and under the conditions outlined in Example 1, 300 cm 3 toluene, 36.05 g N-(5'-hydroxy-3'-oxapentyl)-8-aza-2,5,11,14-tetraoxapentadecane and 2.41 g metallic sodium were introduced. After heating at 60° C. for 20 hours and at 90° C. for 4 hours, the sodium had completely reacted. The mixture was then cooled and 52 g polystyrene cross-linked with 2% divinylbenzene and containing 1.3 meq chlorine/g, were introduced.
After 40 hours at 60° C. under a nitrogen blanket, the mixture was cooled, filtered and the polymer washed with water and then with methanol. After drying under vacuum at 50° C., 66 g of the graft polymer were obtained, having the following structural formula: ##STR16##
The degree of grafting is 75%.
EXAMPLE 4
Following the procedure and under the conditions outlined in Example 1, the following materials were introduced: 100 cm 3 toluene, 10.9 g N-(2'-hydroxyethyl)-9-aza-3,6,12,15-tetraoxaheptadecane, and 0.69 g metallic sodium. After 6 hours at 60° C., 4.65 g polystyrene cross-linked with 4% divinylbenzene, and containing 4.3 meq chlorine/g, were added. After 30 hours at 80° C. the mixture was cooled and filtered. The precipitate was washed with water and methanol and then dried at 50° C. under vacuum. 5 g of the graft polymer were obtained, having the following structural formula: ##STR17##
EXAMPLE 5
Following the procedure and under the conditions outlined in Example 1, the following materials were introduced: 100 ml toluene, 60 g tris-(8-hydroxy-3,6-dioxaoctyl)amine and 0.69 g metallic sodium. After heating at 50° C. for 24 hours, 5 g polystyrene cross/linked with 2% divinylbenzene, and containing 4 meq chlorine/g, were introduced.
After 56 hours at 60° C., the mixture was cooled, filtered and the polymer washed with water and then with methanol. After drying under vacuum at 50° C., 9.5 g of graft polymer were obtained, having the following structural formula: ##STR18##
The degree of grafting was 63%.
EXAMPLE 6
The compound prepared in Example 1 was used to effect the following reaction: ##STR19##
Into a 100 ml reactor equipped with a reflux condenser and a magnetic stirrer, 37 g toluene, 3.77 g phenol, 6.6 g n-bromohexane and 2.8 g K 2 CO 3 were introduced, together with 0.96 g of the product obtained according to Example 1. The mixture was heated with reflux under agitation for 20 hours and then cooled. The yield in 1-phenoxyhexane was 80%. The mixture was filtered and the precipitate obtained was washed with water and then methanol. After drying at 50° C. under vacuum, 0.94 g polymer, identical to the one introduced, were obtained.
Recycling in a subsequent reaction afforded the same result.
Without the catalyst, the degree of transformation was 10% after 20 hours.
EXAMPLE 7
The compound prepared in Example 1 was used in the following reaction: ##STR20##
Into a 100 ml reactor equipped with a reflux condenser and a magnetic stirrer, 17 g 1-chlorooctane, 1.16 g anhydrous sodium phenate and 0.31 g of the product prepared according to Example 1, were introduced. The mixture was heated to 140° C. for 3 hours, 30 minutes. 1-Phenoxyoctane was obtained in a yield of 96%. The mixture was filtered after cooling and the precipitate washed with water and methanol.
After drying at 50° C. under vacuum, 0.30 g polymer was recovered. Recycling of the product in a subsequent experiment afforded identical results.
While the invention has been described in terms of various preferred embodiments, the skilled artisan will appreciate that various modifications, substitutions, omissions, and changes may be made without departing from the spirit thereof. Accordingly, it is intended that the scope of the present invention be limited solely by the scope of the following claims. | Novel sequestering agents useful for the extraction of metal values and in various organic syntheses comprise a cross-linked organic polymeric substrate, said substrate having covalently coupled thereto a plurality of functional groups, the free valence of which having the structural formula: ##STR1## wherein R 1 , R 2 , R 3 , R 4 , R 6 and R 7 , which are identical or different, each represents a hydrogen atom or an alkyl radical having 1 to 4 carbon atoms, R 5 and R 8 , which are also identical or different, each represents a hydrogen atom, an alkyl or cycloalkyl radical having 1 to 12 carbon atoms, a phenyl radical, a --C g H 2q --φ or C q H 2+1 --φ-- radical, and further wherein q ranges from 1 to about 12, and n, m and p, which are also identical or different, range from 1 to 10, and φ is phenyl. | 2 |
FIELD OF THE INVENTION
[0001] The present invention relates to inventory management. In particular, the present invention relates to systems and methods for product selection, retrieval and delivery.
BACKGROUND OF THE INVENTION
[0002] Inventory management systems have been used for years by manufacturers, retailers, wholesalers, and other businesses. Some of these systems allow business to link customer purchases to restocking orders. Other systems allow customers to select a product and have that product delivered to a pick-up area without the need for the customer to actually handle the product. For example, retailer, Service Merchandise (tm), required customers to select a tag corresponding to a product and present that tag to a customer service representative at the checkout counter. Once the customer had paid for the product, an order indicating the customer and the purchased product was relayed to a product warehouse. Warehouse personnel then retrieved the purchased product and delivered it to the waiting customer. Of course, the customer did not get the actual product that he saw on the showroom floor. Instead, the customer received a product of the same type as the product on the showroom floor.
[0003] The above-described inventory management system is generally adequate for fungible items such as TVs and stereos because the customer does not care which particular product is delivered. Rather, the customer only cares that the delivered product is of a certain brand and model. In other words, the customer only wants the delivered TV to match the TV on the showroom floor.
[0004] Although the Service Merchandise-type inventory management system is adequate for fungible items, it is completely unsatisfactory for non-fungible items. For example, present inventory management systems are practically useless for nurseries because each plant at a nursery is unique, and because customers want to purchase a specific plant rather than a particular type and size of plant. Accordingly, a system and method are needed to manage inventories that include non-fungible products. In particular, a system and method are needed to aid in the selection, location, retrieval and delivery of non-fungible products.
SUMMARY OF THE INVENTION
[0005] Exemplary embodiments of the present invention that are shown in the drawings are summarized below. These and other embodiments are more fully described in the Detailed Description section. It is to be understood, however, that there is no intention to limit the invention to the forms described in this Summary of the Invention or in the Detailed Description. One skilled in the art can recognize that there are numerous modifications, equivalents and alternative constructions that fall within the spirit and scope of the invention as expressed in the claims.
[0006] In one embodiment, the present invention includes a system and method for selecting, locating, retrieving and delivering non-fungible products. For example, a customer can initially select a particular product for purchase. The customer can make this selection in a variety of ways. For example, the customer can scan a barcode attached to the product. Alternatively, the customer can electronically read information from the product through means such as RF. In yet other embodiments, the customer could remove a tag from the product and take the tag to a customer service representative for scanning.
[0007] After the customer selects the product for purchase, a unique identifier for that product can then be provided to an order processing system (“OPS”). The OPS can then compare the unique identifier to a product database and determine a location for the product. Alternatively, the unique identifier could include the product's location information. Whether the location information is contained in the unique identifier or retrieved from a product database, the OPS can relay the unique identifier, the product location and other useful information to a delivery system. The delivery system can then schedule the retrieval and/or pickup of the selected product. For example, the delivery system could relay the unique identifier and the location to delivery personnel who could then retrieve the exact product that the customer selected and deliver that product to the customer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Various objects and advantages and a more complete understanding of the present invention are apparent and more readily appreciated by reference to the following Detailed Description and to the appended claims when taken in conjunction with the accompanying Drawings wherein:
[0009] [0009]FIG. 1 is a flowchart showing one method in accordance with the present invention;
[0010] [0010]FIG. 2 is a block diagram showing a system in accordance with the present invention;
[0011] [0011]FIG. 3 illustrates an identification tag that can be attached to a non-fungible product;
[0012] [0012]FIG. 4 is a flowchart showing another method in accordance with the present invention;
[0013] [0013]FIG. 5 illustrates a wireless device for use in the method of FIG. 4; and
[0014] [0014]FIG. 6 is a flowchart of a method for determining the placement of non-fungible products within an inventory layout.
DETAILED DESCRIPTION
[0015] Referring now to the drawings, where like or similar elements are designated with identical reference numerals throughout the several views, and referring in particular to FIG. 1, it is a flowchart showing one method in accordance with the present invention. In this embodiment, a customer initially selects a unique, e.g., non-fungible, product for purchase. The customer can select the product, for example, by electronically reading the product's identifying information or by manually collecting that information through, for example, removable tags (step 105 ).
[0016] Once the product's identifying information is collected, the product information is next transferred from the customer to a point of sale (“POS”) device or an order management system. When the product information is transferred to the POS, a total purchase price can be calculated and collected (step 110 ). In some embodiments, the POS device, or a connected device, may recommend related products. For example, if a purchased plant has unique fertilizer needs, an appropriate recommendation can be generated.
[0017] After the selected products have been purchased, the relevant product information can be transferred to a delivery management system, which could be a centralized or distributed location (step 115 ). For example, the product information could be transferred to a centralized delivery management system that can queue and schedule product retrievals and deliveries. For example, the delivery management system could determine that a particular order should be retrieved next and that the order should be delivered to a particular staging area. In alternate embodiments, the order retrieval could be divided into smaller jobs (step 120 ). For example, in a nursery, a first delivery agent could be assigned to the tree section and a second delivery agent assigned to the flower section. When an order is received that includes both trees and flowers, the delivery management system could divide the order and send the tree portion to the first delivery agent and the flower portion to the second delivery agent. The two agents could then retrieve their individual portions of the order and deliver them to the customer.
[0018] In one embodiment, after locating the product selected by the customer, the delivery agent can electronically read the identifying information from the product (steps 125 and 130 ). For example, the delivery agent could scan the product's tag. The results of the scan could then be relayed to the order processing system (OPS) for matching against the customer's order (step 135 ). If the scanned product does not match the customer's order, the OPS can notify the delivery agent. Otherwise, the product can be delivered to the customer (step 140 ).
[0019] [0019]FIG. 2 is a block diagram of a system 145 in accordance with one embodiment of the present invention. In this embodiment, a customer identifies a product 150 , such as a particular tree, and either scans a tag 155 (shown in detail in FIG. 3) attached to the product or removes a tag from the product for future scanning at, for example, a customer service scanning station 160 . The customer can scan the label with a non-wireless scanner, wireless-scanner or a scanning-enabled PDA. The scanning device 165 can either locally store the information until the order is finalized or wirelessly relay the product information to an OPS prior to the entire order being finalized 170 . For example, the scanning device 165 could store the information and download it directly to a POS device 175 or wirelessly relay the product information to a POS device 175 or an OPS 170 .
[0020] When product information is relayed to the POS device or the OPS, that device can then determine pricing information, discount information, sale information, upsell information, etc. Portions of this information can then be relayed back to the customer's scanning device 165 and subsequently displayed for the customer. In other embodiments, the customer's scanning device 165 could be directly loaded with the relevant information, thereby eliminating the need for the wireless connection.
[0021] When the scanning device 165 is wirelessly connected to the OPS 170 , the customer can finalize an order or portion of an order by activating the appropriate feature on the scanning device 165 . The scanning device 165 can then relay the order information to the POS device and/or the OPS (which could be integrated into a single unit) 110 . The appropriate device can then adjust the customer's account and relay the order information to the delivery management system 180 . A unique identifier for the selected product and the location of that product, both of which are generally included in the order information, can be forwarded to delivery personnel 185 who can locate and retrieve the exact product that the customer selected and then deliver it to the customer. Thus, in the case of a nursery, a customer is never required to actually handle the usually heavy, cumbersome and dirty plants.
[0022] Because many customers may be adverse to technology, an alternate product selection means is needed. Accordingly, in one embodiment, customers merely remove, rather than scan, the tag 155 from the exact product in which they are interested. Customers can then take the tags to a POS device 175 and proceed through a standard check out. A sales agent, for example, can scan the tags 155 for the customer and possibly collect payment. Information regarding the purchased products can then be relayed to the OPS 170 and to the delivery personnel 185 .
[0023] Referring now to FIG. 4, it is a flowchart of another method in accordance with the present invention. In this embodiment, a customer, or the customer' agent, initially establishes an account (step 190 ). A typical account could indicate a credit line, a delivery address, and delivery instructions. For example, a customer's account could indicate a $1,000 line of credit, the customer's home for a delivery address, and a delivery schedule to be determined by a landscaper. Such an account could be particularly beneficial to general contractors, landscapers because they could establish an account for each project and let the customer select the plants to be used in the project. After the customer selects the plants, the contractor would then have the ability to control the delivery date and delivery location.
[0024] Still referring to FIG. 4, after the customer's account has been established, the customer can select the particular products of interest and either scan or collect their tags. When a tag is scanned, the price of the product can be compared against the balance of the customer's account and, assuming the account has enough credit, the sale can be finalized and the customer's account adjusted (steps 195 , 200 and 205 ). The product's identifying information can then be transferred to the delivery management system and to the delivery personnel who can retrieve and deliver the product (steps 210 , 215 and 220 ).
[0025] Referring now to FIG. 5, it illustrates one embodiment of a scanner 230 for use in certain embodiments of the present invention. This scanner 230 includes a wireless computer device with an integrated barcode reader. As the customer selects products, related product information appears on the display screen. The displayed information could come directly from the scanned tag, or the displayed information could be retrieved from a remote database. As can be appreciated by those of skill in the art, other scanning devices, with or without a display screen, can also be used.
[0026] Referring now to FIG. 6, it is a flowchart of a method for determining the placement of non-fungible products within an inventory layout. In this embodiment, a business receives a non-fungible inventory item from a supplier (step 240 ). For example, the business could receive a new six-foot oak tree from a tree farm. Data regarding the product could then be entered into an inventory management system that could record that the product was received and recommend where within the business to physically locate the product (step 245 ). For example, the inventory management system could determine that all oak trees are located in zone A of the business and that six-foot oak trees are located in subzone 3 . Thus, the inventory management system could recommend that the new oak tree should be located somewhere in zone A, subzone B.
[0027] In particular, the inventory management system could search for empty spaces or bins within that zone and subzone (step 250 ). For example, the inventory management system could keep a record of each product sold and the physical location, e.g., zone, subzone, and/or space) within the business from which that product came. When a product is sold or otherwise disposed of, the space from which it came can be marked as empty. Thus, the inventory management system could search for “empty” spaces corresponding to the characteristics of the received inventory item.
[0028] Once an empty space in which to locate the inventory item has been identified, a tag identifying the inventory item and the recommended location can be printed and secured to the inventory item (step 255 ). The inventory item then can be physically moved to the identified space, and the inventory management system can mark the space as “occupied” (step 260 ).
[0029] In conclusion, the present invention provides, among other things, a system and method for managing, retrieving and/or delivering non-fungible products. Those skilled in the art can readily recognize that numerous variations and substitutions may be made in the invention, its use and its configuration to achieve substantially the same results as achieved by the embodiments described herein. Accordingly, there is no intention to limit the invention to the disclosed exemplary forms. Many variations, modifications and alternative constructions fall within the scope and spirit of the disclosed invention as expressed in the claims. | A system and method for inventory management is described. A method for managing an inventory, the method comprising. In one embodiment, the method includes the steps of establishing an account for a customer; receiving product information, the product information corresponding to a non-fungible product selected by the customer; verifying that the account balance is equal to or greater than a cost associated with the selected product; adjusting the account balance by the cost associated with the selected product; determining a location for the selected product; and transferring the unique product identifier and the determined location to a delivery device. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of application Ser. No. 09/657,824, filed Sep. 8, 2000, abandoned.
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates in general to an improved riser pipe for offshore fluid operations, and in particular to an improved apparatus and method for forming composite pipe structures. Still more particularly, the present invention relates to an improved apparatus and method for securing tubular liners inside composite riser pipes for offshore fluid operations.
2. Description of the Prior Art
Tubular liners for pipes are fairly well known in the prior art. For example, in FIG. 1 of U.S. Pat. No. 4,813,715, a tubular liner 18 is located within a composite drill pipe 10. Each axial end of liner 18 is secured to the ends of drill pipe 10 with a metal connector 30. Another example is illustrated in FIG. 3 of U.S. Pat. No. 5,332,049, wherein a rubber liner 38 is bonded to the interior surface of a composite pipe 34. The ends of liner 38 are secured to pipe 34 with metal connectors 28, 30. In each example, the liners protect the interior surfaces of the composite pipes from pressurized drilling mud and/or other environmental concerns that could damage the non-metallic materials used in the pipes.
Prior art liners for composite pipes are typically bonded to the metal end fittings and/or composite tube of the pipe to form seals. However, adhesives for sealing liners to composite tubes are very sensitive to the manufacturing process. As a result, bonded liners may not be sufficiently reliable for oilfield applications. Moreover, when a liner is bonded, it is permanent and not capable of being reused. Bonded liners also require greater care and assembly time in order to cure the adhesive. Furthermore, the material that is used to form the liner can limit the ability of the liner to form a strong, reliable adhesive bond to the composite pipe and metal end fittings. Thus, an improved apparatus and method for joining liners to composite pipes with metal end fittings is needed to overcome the problems and limitations of the prior art.
SUMMARY OF THE INVENTION
In this invention, the pipe assembly has a tubular member with connectors joined to each end. The connectors serve to connect the pipe assembly to other pipes and are preferably secured to the pipe assembly by adhesive. The connector has a bore with an internal seat. Optionally, the seat may contain axial grooves and may be tapered depending upon the application. The liner inserts through the tubular member, and the ends of the liner are radially deformed against the seats. An inner ring is positioned within the liner to retain the ends of the liner in engagement with the seats. The inner ring may be secured by threads in the bore of the connector in one embodiment. The inner ring may also be radially and plastically deformed into engagement with the seats. In one version of the invention, a flaring tool is used to flare the axial ends of the liner prior to assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric schematic view of a connector constructed in accordance with a first embodiment of the present invention.
FIG. 2 is a sectional side view of the connector of FIG. 1 .
FIG. 3 is an isometric view of an inner ring constructed in accordance with the first embodiment of the present invention.
FIG. 4 is a sectional side view of the inner ring of FIG. 3 .
FIG. 5 is an isometric view of a flaring tool utilized in the method of assembling the first embodiment of the present invention.
FIG. 6 is a schematic sectional side view of the method of the first embodiment of the present invention at an initial stage of assembly.
FIG. 7 is a schematic sectional side view of the method of the first embodiment of the present invention at a second stage of assembly.
FIG. 8 is a schematic sectional side view of the method of the first embodiment of the present invention at a third stage of assembly.
FIG. 9 is an enlarged, schematic, sectional side view of the first embodiment of the present invention after final assembly.
FIG. 10 is an isometric schematic view of a connector constructed in accordance with a second embodiment of the present invention.
FIG. 11 is a sectional side view of the connector of FIG. 10 .
FIG. 12 is an isometric schematic view of an inner ring constructed in accordance with the second embodiment of the present invention.
FIG. 13 is a sectional side view of the inner ring of FIG. 12 .
FIG. 14 is an isometric view of a raming mandrel utilized in the method of assembling the second embodiment of the present invention.
FIG. 15 is a sectional side view of the raming mandrel of FIG. 14 .
FIG. 16 is a partially-sectioned, isometric view of the method of the second embodiment of the present invention during assembly.
FIG. 17 is an enlarged, schematic, sectional side view of the second embodiment of the present invention after final assembly.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 2 , an outer ring or connector 11 for use in a first embodiment of the present invention is shown. Connector 11 is shown schematically as a test or prototype unit. Connector 11 is a hollow, metal, tubular member having an axis 13 and a bore of varying diameter. The rearward portion 15 of the bore is generally cylindrical, and a seat 17 adjoins and is forward of rearward bore portion 15 . Seat 17 is tapered or inclined at approximately 20 degrees relative to axis 13 and diminishes in diameter from right to left.
Seat 17 may optionally have a series of internal, axial teeth or grooves 19 . In the preferred embodiment, grooves 19 are circumferential, parallel to one another, and do not form a helical thread. The bore of connector 11 transitions from seat 17 into a generally cylindrical segment 21 , to the right or forward of grooves 19 . A set of threads 25 are formed forward of cylindrical segment 21 . The main body of connector 11 has a set of tapped holes 23 in its right side face that are parallel to axis 13 . Holes 23 are employed for test purposes and not utilized in commercial or production units. Also, in commercial units, the open end of connector 11 is spaced further from threads 25 and a second set of threads (not shown) is located between threads 25 and the open end. The second set of threads enables connector 11 to be connected to other pipe assemblies.
As shown in FIGS. 3 and 4 , an inner ring 31 comprises a separate element from connector 11 . Like connector 11 , inner ring 31 is a hollow, metal, tubular member having an axis 33 and a bore 35 . However, inner ring 31 is smaller in diameter than connector 11 such that inner ring 31 can fit within the bore of connector 11 , as will be described below. Bore 35 and the outer or retaining surface 37 of inner ring 31 are generally cylindrical, but outer surface 37 has a short, 20 degree taper 39 on its left side edge that diminishes in diameter from right to left. Taper 39 is a smooth conical surface in the preferred embodiment. An annular flange 41 is shown extending from the right side edge of inner ring 31 . Flange 41 is used for test fixture purposes and is eliminated in production inner rings 31 . Flange 41 has a set of through-holes 43 that are parallel to axis 33 . Inner ring 31 also has external threads 45 on its outer surface 37 .
Referring now to FIG. 5 , a flaring tool 51 that is utilized in a method of assembling the first embodiment of the present invention is shown. Flaring tool 51 is similar in size and geometry relative to inner ring 31 , except that it is a bull-nosed solid member rather than hollow. Like inner ring 31 , flaring tool 51 has a cylindrical outer surface 53 with a 20 degree taper 55 on its left side edge, and a flange 57 with holes 59 . However, taper 55 has a greater axial dimension than taper 39 on inner ring 31 .
In operation, the previously described elements of the first embodiment are used to secure a liner in a pipe having connectors on each end. FIG. 6 schematically depicts components of a drilling or production riser, which include a fiber and resin composite tubular member 61 that has each end (only one shown) joined to connector 11 . Connector 11 has a bonding surface 63 to which an end of tubular member 61 is adhesively secured axially in an end-to-end interface. FIG. 6 depicts a test unit, and in the actual production unit, a sleeve portion (not shown) of connector 11 extends rearwardly and receives a forward portion of the end of tubular member 61 . Tubular member 61 is also adhesive bonded between its outer diameter and the inner diameter of rearward extending sleeve portion.
A thin wall tubular liner 65 of elastomeric material is located within tubular member 61 . Liner 65 is precisely sized to be closely received by the internal diameter of tubular member 61 . At the initial phase of assembly shown in FIG. 6 , liner 65 has an axial length that exceeds the axial length of tubular member 61 . Hence, an end portion 67 of liner 65 extends beyond each axial end of tubular member 61 and into the bore of each connector 11 . End portion 67 extends through entry bore portion 15 and seat 17 , but not into cylindrical segment 21 of connector 11 .
In the next step of the first embodiment ( FIG. 7 ), flaring tool 51 is inserted into each axial end of the assembly to plastically deform end portions 67 of liner 65 into frusto-conical flares ( FIG. 8 ). The flaring tool 51 is preferably heated to 200–250 degrees F. prior to flaring. The taper 55 on flaring tool 51 engages end portion 67 and defects it outward into the inclined profile of seat 17 . During this operation, outer surface 53 of flaring tool 51 is closely received by cylindrical segment 21 of connector 11 to prevent excessive movement therebetween. If necessary to effect the flares, flaring tool 51 may be temporarily secured to connector 11 by inserting threaded fasteners (not shown) into holes 59 , 23 . Liner 65 is sufficiently restrained during this operation to prevent incidental movement relative to the overall assembly. After end portions 67 are formed into the permanent flares, flaring tool 51 is removed from connector 11 ( FIG. 8 ) for completion of the assembly.
In the final step of the first embodiment ( FIG. 9 ), inner ring 31 is inserted into connector 11 as shown with a sealing O-ring 69 therebetween. Various spacer rings 71 and shims 73 are shown in FIG. 9 as they form a part of a test fixture. Such are not used in production pipe assemblies. External threads 45 on the outer shoulder of inner ring 31 abut internal threads 25 on the internal shoulder of connector 11 . The taper 39 on inner ring 31 forces the outer surface of the flared end portion 67 into the internal grooves 19 of connector 11 . Grooves 19 serve as retaining surface and provide enhanced grip on liner 65 between connector 11 and inner ring 31 . Threads 45 on inner ring 31 engage internal threads 25 in connector 11 to retain inner ring 31 with connector 11 . Thus, each axial end of liner 65 is securely restrained within the assembly of tubular member 61 and connector 11 to prevent movement therebetween.
Liner 65 is replaceable since it is merely flared and not bonded to the assembly. It is replaced by unscrewing each inner ring 31 , then gripping liner 65 and pulling it from tubular member 61 . The bonding between tubular member 61 and connector 11 remains undisturbed during the removal and replacement of liner 65 .
Referring now to FIGS. 10 and 11 , a test prototype of a connector 111 for use in a second embodiment of the present invention is shown. Connector 111 is a hollow, metal, tubular member having an axis 113 and a generally smooth, cylindrical bore portion 115 on a right side. A cylindrical seat 117 adjoins the left side of bore 115 . Seat 117 is slightly smaller in diameter than bore 115 and optionally may have a series of internal, axial teeth or grooves 119 . In the preferred embodiment, grooves 119 are parallel to one another and do not form a helical thread. The main body of connector 111 has a set of tapped holes 121 ( FIG. 10 ) in its right side face that are parallel to axis 113 . Holes 121 are used for test purposes, not in production models. Connector 111 has an internal shoulder 123 located between bore 115 and seat 117 . In the commercial version of connector 111 (not shown), threads are located in the bore of connector 111 for connecting it to other pipe assemblies.
As shown in FIGS. 12 and 13 , an inner ring 131 comprises a second element of the second embodiment of the invention. Like connector 111 , inner ring 131 is a hollow, metal, tubular member having an axis 133 and a generally cylindrical bore 135 . However, inner ring 131 is smaller in diameter and shorter in length than connector 111 such that inner ring 131 can fit wholly within the bores 115 , 117 of connector 111 , as will be described below. Bore 135 and the outer surface 137 of inner ring 131 are generally cylindrical, except for an outer tapered surface 139 near its midsection that diminishes in diameter from right to left. Taper 139 could be replaced by a cylindrical surface. A series of axial teeth or grooves 141 that are complementary in profile to grooves 119 in connector 111 may optionally be located to the left of taper 139 . Inner ring 131 also has an outer shoulder 143 located between outer surface 137 and taper 139 . Outer shoulder 143 is utilized in the test fixture model of FIG. 17 , but could be eliminated.
Referring now to FIGS. 14 and 15 , a hardened ramming mandrel 151 that is utilized in a method of assembling the second embodiment of the present invention is shown. Ramming mandrel 151 is essentially toroidal or donut-like in shape. Ramming mandrel 151 has a rounded outer surface 153 with a maximum diameter that is slightly greater than the minimum inner diameter of inner ring 131 . Ramming mandrel 151 also has an axial through hole 155 . A mandrel with an expandable annular collet could be used as an alternative to ramming mandrel 151 .
A composite fiber and resin tubular member 161 has opposite ends permanently secured to connector 111 . Connector 111 has a bonding surface 163 that is permanently mounted to an axial end of tubular member 161 .The bonding is preferably by adhesive. In the commercial model (not shown) for a production riser pipe, rather than the test prototype shown in FIG. 17 , connector 111 has a rearward extending sleeve over which the end of tubular member 161 extends. The bonding surface in the commercial version is thus the outer diameter of this sleeve portion and an inner diameter of tubular member 161 near its end.
As shown in FIG. 17 , an elastomeric liner 165 is inserted into tubular member 161 . Liner 165 has an axial length that exceeds the axial length of tubular member 161 . Hence, the end portions 167 of liner 165 extend beyond each axial end of tubular member 161 and into connector 111 . Liner end portion 167 extends through seat 117 , but not into cylindrical bore 115 of connector 111 . Inner ring 131 is located within connector 111 , and may have an optional O-ring 169 for providing a seal therebetween. Outer shoulder 143 on inner ring 131 abuts inner shoulder 123 in connector 111 in this test fixture version.
In the next step of the second embodiment ( FIG. 16 ), ramming mandrel 151 is mounted to the shaft 171 of a press 173 and forced into the bore 135 of inner ring 131 as shown. Connector 111 , inner ring 131 , tubular member 161 and liner 165 are secured from extraneous movement. For ease of understanding, some of these elements are not shown in FIG. 16 . The oversized diameter of ramming mandrel 151 is readily received on the larger right side of inner ring 131 . However, as the ramming mandrel 151 moves toward the smaller diameter left side of bore 135 , end portion 167 of liner 165 is plastically deformed between and into grooves 119 and 141 of connector 111 and inner ring 131 , respectively. Inner ring 131 is also plastically or permanently deformed radially outward simultaneously. Grooves 119 , 141 provide enhanced grip on liner 165 between connector 111 and inner ring 131 . The hoop strength of inner ring 131 retains the ends of liner 165 in engagement with the retaining surface of seat 117 . Thus, each axial end of liner 165 is securely restrained within the assembly of tubular member 161 and connectors 111 to prevent movement therebetween. After end portion 167 is deformed, raming mandrel 151 is removed from inner ring 131 ( FIG. 17 ) to complete the assembly.
Liner 165 may be replaced by cutting inner ring 131 with a tool and pulling it from connector 111 . Then liner 165 may be gripped and pulled from tubular member 161 .
The present invention has several advantages including the ability to effect a reliable engagement between a liner and a composite tubular with metal end connectors. The invention may be utilized in drilling risers, production risers, choke and kill lines, and other applications. The liner may be replaced with other liners without affecting the connection between the tubular member and the connectors. . The liner may be reusable as it may be installed without the use of adhesives.
While the present invention has been shown or described in only some of its forms, it should be apparent to those skilled in the art that it is not so limited, but is susceptible to various changes without departing from the scope of the invention. For example, although grooves are shown on the seats, these may be eliminated. If the frictional engagement is sufficient, grooves on the inner ring of the second embodiment may be eliminated. | A device for mechanically securing a tubular liner in a pipe having a tubular member and connectors on each end. The connector has a bore with an internal seat that may have grooves and be tapered depending upon the application. The liner extends through the tubular member into the bore. The ends of the liner are radially and plastically deformed into engagement with the seats. An inner ring is positioned inside the liner to retain the end of the liner in engagement with the seat. The inner ring may be held by threads or by radially and plastically deforming it. The connectors are mounted to the tubular member independently of the liner, such as by adhesive. The liner may be replaced by removing the inner rings without affecting the connection between the tubular member and the connectors. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a voltage regulator of a vehicle AC generator and, particularly, a voltage regulator having a semiconductor switch element for controlling field current to be supplied to a field coil of a vehicle AC generator.
[0003] 2. Description of the Related Art
[0004] A recent voltage regulator of a vehicle AC generator is provided with various electronic circuits, such as a comparator, an operational amplifier, an oscillating circuit and/or the like, disposed in an IC chip. A constant voltage power circuit is also provided in order to supply constant voltage power to such circuits.
[0005] On the other hand, a number of electromagnetic actuators have been mounted in a vehicle. If two or more electromagnetic actuators are turned off concurrently, a large negative surge voltage, such as shown in FIG. 8, is generated in a power line connected to a battery, and the negative surge voltage may be applied to a high-side terminal of the constant voltage circuit. In such a case, the output voltage, i.e. VDD, widely fluctuates, resulting in that the comparator and the oscillator can not operate properly.
SUMMARY OF THE INVENTION
[0006] Therefore, a main object of the invention is to provide an improved voltage regulator that is free from the above stated problems.
[0007] According to a main feature of the invention, a voltage regulator of a vehicle AC generator includes a switching element connected between a battery and a field coil, a circuit for controlling the switching element according to terminal voltage of the battery, a power circuit for providing a constant voltage from power supplied thereto and supplying the control circuit with the constant voltage and a reverse-current blocking diode having an anode connected through an outside power line to the battery and a cathode connected to the power circuit. Even if a large negative surge voltage is generated in a power line connected to a battery and applied to the power circuit, the output voltage, i.e. VDD, does not widely fluctuate, so that devices included in the voltage regulator, such as a comparator or an oscillator, can operate properly.
[0008] Preferably, a portion of the control circuit, the power circuit and the reversecurrent blocking diode are integrated into an IC chip and separated by insulation layers. However, the reverse-current blocking diode may be formed at a portion separate from the IC chip. The IC chip and the portion at which the reverse-current blocking diode is formed may be disposed in a hybrid IC unit.
[0009] It is also preferable that the reverse-current blocking diode is fixed to a first conductive support plate and the power circuit is fixed to a second conductive support plate, and that
[0010] the first and second conductive support plates are thermally and electrically insulated from each other.
[0011] Further, each of the first and second support plates may be comprised of one of leads of a lead frame, the reverse-current blocking diode may have a cathode electrode connected to the power circuit by a bonding wire, and the reverse-current blocking diode, the power circuit and the bonding wires are molded together with resin.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Other objects, features and characteristics of the present invention as well as the functions of related parts of the present invention will become clear from a study of the following detailed description, the appended claims and the drawings. In the drawings:
[0013] [0013]FIG. 1 is a circuit diagram of a voltage regulator of a vehicle AC generator according to a preferred embodiment of the invention;
[0014] [0014]FIG. 2 is a schematic cross-sectional view of a control circuit shown in FIG. 1;
[0015] [0015]FIG. 3 is a circuit diagram of a variation of a power circuit shown in FIG. 1;
[0016] [0016]FIG. 4 is a plan view of a variation of the control circuit shown in FIG. 1;
[0017] [0017]FIG. 5 is a schematic cross-sectional side view cut along line A-A in FIG. 4;
[0018] [0018]FIG. 6 is an enlarged schematic cross-sectional view of a reverse-current blocking diode; and
[0019] [0019]FIG. 7 is a wave form of a negative surge voltage.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] A voltage regulator of a vehicle AC generator according to a preferred embodiment of the invention is described with reference to FIGS. 1 and 2.
[0021] In FIG. 1, an AC generator includes a stator having a stator coil 1 and a rotor having a field coil 2 . When the rotor rotates, AC power is generated in the stator coil 1 . The AC power is rectified by a rectifier circuit 3 so that DC power is supplied to a battery 4 and an electric load 6 . Field current to be supplied to the field coil 2 is controlled by a control circuit 8 .
[0022] The control circuit 8 has a switching element 11 for controlling the field current supplied to the field coil 2 . The switching element 11 is a source-follower type N-channel MOSFET that has a base and a gate. The switching element 11 controls the field current according to the voltage level applied to the base thereof. Reference numeral 12 is a flywheel diode connected in parallel with the field coil 2 . The gate of the switching element 11 is charged by a charge pump circuit 14 until the voltage level of the gate becomes as high as a prescribed level and is discharged by a gate-discharging transistor 17 .
[0023] Terminal voltage of the battery 4 is applied to the control circuit 8 via a battery connection terminal S and is divided by resistors 20 and 21 . The divided voltage is applied to a low-side terminal of a comparator 19 . A capacitor 22 is connected to the low-side terminal of the comparator 19 to bypass ripple components of the battery voltage.
[0024] The divided voltage is compared by the comparator 19 with a reference voltage Vr. If the battery voltage is lower than a prescribed voltage level, the comparator 19 provides an AND circuit 16 and an inverter 18 with a Hi-level signal. Consequently, the inverter 18 turns off the gate-discharging transistor 17 to stop discharging the electric charge from the gate of the switching element 11 . At the same time, the AND circuit 16 applies an output signal of an oscillation circuit 15 to drive the charge-pump circuit 14 , which charges the gate of the switching element 11 to boost the voltage of the gate to a prescribed voltage level, thereby, to turn on the switching element 11 . As a result, the field current is increased, and the output power of the AC generator is increased.
[0025] If the battery voltage is higher than the prescribed voltage level, the chargepump circuit 14 stops charging the gate of the switching element 11 . At the same time, the inverter 18 turns on the gate-discharging transistor 17 to turn off the switching element 11 . As a result, the field current is reduced and the output power of the AC generator is reduced. Thus, the battery voltage is controlled at a level decided by the reference voltage and the voltage divided by the resistors 20 and 21 .
[0026] Operation of the voltage regulator is described below.
[0027] Even if a key switch 5 is turned on while the engine stops the AC voltage is not generated by the AC generator. Therefore, a generation detecting circuit 31 , which detects a phase- voltage of a phase-coil, turns on a switching element 30 to drive a warning lamp 40 . If the engine starts and the AC generator starts generation, the generation detecting circuit 31 detects the phase voltage and turns off the switching element 30 , thereby turning off the warning lamp 40 . The warning lamp 40 can be driven by another signal applied to one of other devices.
[0028] A power circuit 10 is a series circuit of a constant voltage diode 101 and a current limiting element or resistor 102 . The power circuit 10 is energized by the battery 4 via the diode 9 and the key switch 5 to supply various portions of the control circuit 8 with the constant voltage VDD.
[0029] If the electric load 6 is an inductive load, the electric load 6 generates a negative surge voltage, which temporarily lowers the potential of the IG terminal. The reverse-current blocking diode 9 prevents the negative surge voltage from being applied to the power circuit 10 .
[0030] The reverse-current blocking diode 9 is formed at an electrical isolation type integrated circuit that is comprised of other circuits including the current-limiting resistor 102 . The reverse-current blocking diode 9 and other circuits are separated by insulation layers. Reference numeral 200 indicates a low-density P-type base plate, reference numerals 201 , 202 indicate oxidized layers forming a plurality of insulated N-type island regions on the base plate 200 . High-density N-type layers are respectively formed at the bottom of the island regions. Low-density N-type epitaxial embedded layers are also formed on the high-density N-type layers. P-type anode regions 205 , P-type resistor regions 206 , high-density P-type contact region 207 and 208 , and high-density N-type contact regions 209 are also formed one after another, as shown in FIG. 2. The reverse current-blocking diode 9 is formed at the right island region, and the current-limiting resistor 102 is formed aL the left island region in FIG. 2. Thus, the reverse-current blocking diode 9 and other circuits are integrated into one chip, so that the voltage regulator can be made compact.
[0031] A variation of the power circuit 10 is described with reference to FIG. 3, in which reference numeral 105 represents a parallel capacitor, reference numeral 103 represents an emitter-follower transistor, and reference numeral 104 is a collector resistor. The parallel capacitor 105 controls fluctuation of the potential of an internal power line 300 .
[0032] A variation of the control circuit 8 is described with reference to FIGS. 4 - 6 .
[0033] The reverse-current blocking diode 9 is fixed to a lead 510 of a lead frame. As shown in FIG. 6, the reverse-current blocking diode 9 is formed on a P-type base plate 91 to provide a PN junction by N-type diffusion.
[0034] Reference numeral 50 is a heat sink, reference numeral 52 indicates a bonding wire, numeral 53 indicates a mold member, numeral 54 is a conductive member, numeral 105 is a chip capacitor, and numerals 510 - 517 respectively indicate leads. Reference numeral 80 is an IC chip on which the control circuit is formed, and numeral 10 a is a portion on which the power circuit 10 is formed. The IC chip 80 is fixed to the heat sink. The reverse-current blocking diode 9 is comprised of a P-type base plate 91 , an N-type region 92 formed on the base plate 91 and a metal electrode 93 fixed to the N-type region 92 . The chip of the reverse-current blocking diode 9 is fixed to the lead 510 .
[0035] The metal electrode 93 is made of the same material as the bonding wires 52 to prevent the metal electrode 93 from chemically combining with the bonding wires 52 . It is also preferable to use the same material for members connecting the IC chip 80 with the heat sink as the material for the conductive member 54 . The chip capacitor used for the parallel capacitor 105 is disposed between a lead 516 and a lead 517 . The member for connecting the capacitor 105 is made of the same material as the connecting member for the reverse-current blocking diode 9 . However, it is not necessary to concurrently fix the capacitor 105 when the reverse-current blocking diode 9 is fixed. This arrangement prevents deterioration due to metal junction. If the voltage regulator is abnormally heated by the AC generator by accident, all the connecting members may be melted and disconnect the elements of the control circuit 8 . Therefore, current is not supplied to the power circuit of the regulator, so that a highly safe voltage regulator can be provided.
[0036] All the above members are molded with the thermally non-conductive mold member 53 . Therefore, a compact voltage regulator can be provided, and the reverse-current blocking diode 9 is thermally isolated from other elements of the control circuit that includes the switching element 11 . The switching element 11 can be formed at a chip separated from the chip of the control circuit 8 . Even if the switching element 11 is heated when passing the field current, the reverse-current blocking diode 9 is not heated, so that leak current of the reverse-current blocking diode 9 can be limited at a low level.
[0037] In the foregoing description of the present invention, the invention has been disclosed with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made to the specific embodiments of the present invention without departing from the scope of the invention as set forth in the appended claims. Accordingly, the description of the present invention is to be regarded in an illustrative, rather than a restrictive, sense. | A voltage regulator of a vehicle AC generator includes a switching element connected between a battery and a field coil, a control circuit for controlling the switching element according to battery voltage, a power circuit for supplying the control circuit with a constant voltage and a reverse-current blocking diode having an anode connected through an outside power line to the battery and a cathode connected to the power circuit. Even if a large negative surge voltage is generated in a power line connected to a battery, and applied to the power circuit, the output voltage, i.e. VDD, does not widely fluctuate, so that devices included in the voltage regulator, such as a comparator or an oscillator, can operate properly. | 7 |
BACKGROUND OF THE DISCLOSURE
Drill bits are formed on a drill bit body or a set of cones which rotate in the drill bit during drilling. There are two types of tooth constructions that are prevalent today. In one instance, the teeth are fabricated from a unitary piece of metal so that the teeth are part of the drill bit body or cone. In another approach, the cone or bit body is drilled with a number of holes and teeth are inserted. In the latter instance, a harder tooth can be used. Indeed, it is possible to make inserts which mount in the formed holes in the drill bit body, the teeth being formed of much harder materials such as tungsten carbide. That is an extremely hard material. Even so, the insert tends to wear. The insert is normally protected by placing a synthetic diamond layer over the end of the insert. The synthetic diamond is sometimes known as a polycrystalline diamond compact and carries the abbreviation of PDC. In this regard, the PDC layer extends the life of the insert markedly.
The present disclosure is directed to an insert which is an elongate cylindrical body in the preferred embodiment, suitably sized and shaped, so that it fits in a hole formed in the drill bit body or some part of the bit body, and is equipped with a PDC crown or cap attached to the end of it. Such devices have been made heretofore. The present disclosure however sets forth a PDC protected insert which is ideally constructed for use in a drag bit. By way of background, some bits operate so that the teeth of the drill bit (of whatever construction) cut material by rolling so that the tooth is rolled into contact against the face of the partly finished borehole, and there are others that move the drill bit teeth across the face in a dragging motion. The roller bit construction involves a rotational movement of some part of the drill bit so that the tooth is loaded and rolls under load. This causes a crushing motion. By contrast, the tooth in a drill bit which drags across the working face operates in a different fashion. Loosely, it cuts a groove by chiseling or gouging the working face. This involves a sliding motion or a transverse motion across the face of the well borehole. Thus, the dragging motion creates a different kind of drilling motion in contrast with the rolling motion mentioned above.
The present disclosure is directed to a drag bit insert and to a drag bit insert which is constructed in a way so that the drag bit teeth last much longer. To last longer, the drag bit is equipped with teeth having the PDC crown formed on the end of the insert. Moreover, the end of the PDC insert is preferably circular so that the insert is covered completely at the end. When this is done, the covered portion of the insert is exposed to abrasion and tends to wear away. The insert body is constructed with a crown over a circular end face to assure a specified thickness of PDC material on the end of the insert. In addition to that, the insert (before the PDC layer is attached) is provided with two chamfered faces. The chamfered faces are located on opposite sides of the insert body. The tapered and chamfered faces enable the PDC material to provide an enhanced region of PDC material on the insert, thereby extending the life even when subject to losses of material due to abrasion. More particularly, the drag bit insert is installed so that the PDC crown on the end of the insert cylindrical body is joined to a larger surface area. So to speak, the insert body has a uniform conic face joined to the PDC crown except at the upstream and downstream sides of the insert body. Those are enhanced.
The present disclosure enhances performance of the insert, typically made of tungsten carbide by the incorporation of two chamfered faces which are ideally arranged 180° spacing around the body. The two or more chamfered faces are cut at an angle in the range of about 15° to about 45° with respect to the centerline axis of the insert body. The two insert chamfers thereby extend the PDC contact region. The chamfered areas form a longer skirt or face at which abrasion occurs.
Summarizing the present invention, it preferably comprises a right cylinder construction insert preferably formed of hard metal. While other hard materials can be used, an enhanced version of the equipment incorporates a tungsten carbide insert body. The tungsten carbide body is shaped with a pair of spaced. chamfered surface areas. These define chamfered areas which are approximately planar, which extend at an angle of about 15°-45° with respect to the center axis of the insert body, and which extend to a greater length along the sides so that the PDC interface with the insert body is much greater. This improves fastening of the PDC crown to the insert body and lowers heat buildup during drilling or other cutting and abrasive applications.
IN 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.
FIG. 1 of the drawings is a side view showing the insert of the present disclosure provided with a PDC crown which is adhered by joining to the end of the insert body which incorporates a pair of spaced chamfered faces; and
FIG. 2 is an end view of the crown on the insert body of FIG. 1 further illustrating in dotted line the top most end face of the insert.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Attention is now directed to FIG. 1 of the drawings where the numeral 10 identifies the fabricated insert of the present invention. More particularly, the insert is formed with a tooth body 12 of any suitable length. It is preferably a right cylindrical construction. The insert body is formed of tungsten carbide particles in a supportive matrix. In either event, the insert has a length and diameter to enable mounting in a hole formed for that insert in a drill bit body or cone. The insert 12 is typically assembled to the body by an interference fit or brazing to assure that the insert does not wear or break free. It is installed so that the insert body is able to extend to a specified height.
The insert body 12 is shown with a portion broken away to thereby represent that portion in sectional view. The upper end of the fabricated tooth has been broken away to illustrate the end of the tooth and the PDC layer in sectional view as will be explained. The insert body terminates at a circular region of reduced diameter in comparison with the diameter of the tooth. This is shown in FIG. 1 of the drawings where the numeral 14 represents the circular face. The dotted line representation at 16 is circular except for two or more straight edges at 18 and 21). The edges at 18 and 20 are straight line segments associated with enhanced chamfered flat faces extending at an angle downwardly with respect to the centerline axis of the tooth 12. The centerline axis is defined by the cylinder comprising the insert body. The edges 18 and 20 shown in FIG. 2 of the drawings are the upper ends of the chamfered faces 22 and 24. The faces 22 and 24 are preferably inclined at an angle with respect to the vertical of about 15° up to about 45° . The faces 22 and 24 are therefore longer than the cylindrical skirt area below the curved end face 14. Indeed, these two chamfered faces are preferably located at 180° with respect to the centerline axis of the right cylinder construction. Therefore and summarizing the significance of the faces 22 and 24, they are identical in construction, separated by 180° around the cylindrical body 12, and extend to a greater length along the side of the body. This therefore means that the PDC layer which will be described in the next paragraph has a greater contact area and mass at the cutting point.
A PDC layer is formed integrally against the body. In this particular instance, the PDC layer 30 has an encircling skirt 32. The skirt 32 has a greater contact surface area at the notches 22 and 24. In other words, the enhanced contact area increases the grip between the PDC layer and the hard metal insert 12. The PDC layer is constructed with a top most face 34 which is exposed for wear. Furthermore, the top face 34 has the shape of a circle when originally manufactured. It is a circular face which extends across the end of the body to a requisite thickness. As a representative example, the thickness is about 1 mm up to about 4 mm. The diameter of the end face is dependent on the size of the insert. The insert can have a diameter as much as about 20 mm. It is uncommon to make an insert which is larger than that. It is however practical in this instance to make the PDC layer 30 so that it is the sole and only contact material involved in the cutting process. This extends the life of the insert substantially.
An arrow has been included in FIG. 1 of the drawings to show the motion of the insert 10 with respect to the working face of the borehole during drilling. It is therefore helpful to arrange the drill bit insert on the finished bit so that the direction of movement is known. In this particular instance, the dragging motion which occurs during drilling tends to wear the drill bit insert 10 in such a fashion that the enhanced grip at the tapered faces 22 and 24 holds the PDC layer on the metal insert body 12.
The PDC layer is preferably sintered to the metal insert. This forms a layer that is relatively thin, and has been omitted from the drawings for sake of clarity. It is possible to integrally cast the PDC material in this shape. This is done in a mold at elevated pressure and temperature. Molding in place with a braze layer likewise is an adequate approach to attachment of the PDC layer to the metal insert.
In the completed device, the metal insert is constructed first. It is cut with a circular skirt around the circular end at 14. The tapered faces are formed at this time also. This locates the two faces 22 and 24 in the 180° spacing that is illustrated in the drawings. This assures the faces 22 and 24 have a length which is sufficient for attachment. At the time of installation, the insert may be placed by interference or brazing into a hole formed in the drill bit. Care must be taken to assure that the faces 22 and 24 are oriented so that the drag bit operation is certainly obtained. Finally, the device during installation is used to the point in time that the tooth breaks or the PDC crown is completely worn away. This however denotes an extremely long life insert.
While the foregoing is directed to the preferred embodiment the scope is determined by the claims which follow. | A drag bit is formed of an elongate tooth made of tungsten carbide and having an elongate right cylinder construction. The end face is circular at the end of a conic taper. The tapered surface is truncated with two 180° spaced flat faces at 15° to about 45° with respect to the axis of the body. The end is capped by a PDC layer. | 4 |
RELATED APPLICATIONS
The present application is related to commonly assigned U.S. patent application Ser. No. 09/855,486, entitled, “BACKSIDE ALIGNMENT SYSTEM AND METHOD”, filed on May 14, 2001, now U.S. Pat. No. 6,525,805.
FIELD OF THE INVENTION
The present invention relates to alignment systems in optical apparatus, and in particular relates to a system and method for characterizing machine alignment offsets for lithography systems to provide for job portability between the lithography systems.
BACKGROUND OF THE INVENTION
In the manufacturing micro-devices (e.g., integrated circuits, thin-film head and ink jet heads) the processing steps include exposing a substrate, such as a semiconductor wafer coated with photosensitive material, using a lithographic exposure system. This exposure requires aligning the substrate residing on a substrate (wafer) stage, to a reticle having a pattern of a particular device layer, and residing on a reticle stage. In this regard, the lithographic system includes an alignment system, such as that disclosed in U.S. Pat. No. 5,621,813 (referred to hereinafter as “the '813 patent”), which patent is incorporated herein by reference. After alignment, the reticle is exposed to radiation to which the photosensitive coating is sensitive, to transfer the reticle pattern onto the wafer. This alignment and exposure can be performed on a variety of lithography systems such as step and repeat, projection, contact and proximity systems, for example. Typically, the first of such device layers is aligned to some marking on the wafer, for example, to a flat or notch, as is well known. Subsequent layers are then aligned relative to this first layer and/or to each other.
Most exposure systems utilize some mechanical means of pre-aligning the wafer, so that the wafer is coarsely aligned to the reticle. The pre-alignment may be, for example, a mechanical means of locating a flat or notch on the wafer. Alternatively, optical sensors may determine the location of the flat, notch, or peripheral edge of the wafer. These methods typically align the wafer to an accuracy of a few hundred microns. After mechanical pre-alignment, the wafer is moved to or near the exposure position by, for example, a wafer-handling arm. Often, after the above-described mechanical alignment, but prior to fine alignment, a pre-alignment using a photoelectric detector is performed. Special optical alignment targets (OATs), produced on the substrate by previous processing steps, are used for this purpose. The OATs are relatively large, so that they can be quickly found after the relatively coarse mechanical pre-alignment. This pre-alignment using the OATs typically aligns the wafer to within approximately ±50 microns or better. At this point, a fine alignment may be performed, by aligning alignment keys on the reticle to alignment targets on the wafer.
The alignment keys and targets are typically on the order of a few microns in size, and provide for alignment to a precision of, for example, 0.15 micron or less, depending upon the requirements of the user. The fine alignment can be performed via a photoelectric detector, such as photomultiple tube or CCD array, which can detect the superposition of special-purpose alignment marks on the reticle and wafer. Based upon the superposition signal level, the detection apparatus sends a signal to move the wafer and/or reticle stage such that the alignment targets on the wafer are in alignment with the alignment keys on the reticle.
The alignment system may be an off-axis system, wherein the wafer is aligned out of the exposure of field of the optical system, then moved to the exposure field with high accuracy to align the wafer to the reticle. Alternatively, the alignment can be performed “through the lens” (TTL) of the optical system. This is also called “on-axis” alignment, and the wafer remains in place during such alignment. Some off-axis alignment systems rely upon aligning the reticle to a mechanical reference built into the lithography system. The substrate is aligned to this mechanical reference as well, and thus to the reticle by commutation. However this scheme requires that the mechanical reference be frequently calibrated for the offset of the substrate to the reticle. Furthermore, very high mechanical stability is required. The TTL technique allow the examination of the actual superposition of reticle image and the substrate for alignment, thereby eliminating the need for a mechanical reference. A TTL system can be configured in a variety of ways, for example, the prior art method of using the projection lens (or a portion of the projection lens) to view the projection of the reticle image onto the substrate. Many alignment systems require scanning, that is, relative motion between the reticle and wafer, which introduces some error.
A problem in present-day lithography practice is that each lithography system has a particular hardware-dependent alignment offset, making it difficult and time-consuming to run different processes on different systems unless the offset is known for the particular tool. Making matters worse is the fact that each “job” has a job-dependent alignment offset. Here, a “job” denotes a different process step carried out on the machine that involves a different reticle to be exposed. Thus, if a particular lithography system used for a given step breaks down, an otherwise available lithography system cannot be used in its place without a great deal of inconvenience in characterizing the offset for the available machine for the particular job that needs to be run.
The prior art method of characterizing alignment offsets for a particular job being run on a particular lithography system (hereinafter, “machine”) involves running so-called “send ahead” wafers to measure the alignment offset for each machine and each job. With reference to FIG. 1A , the prior art method involves exposing a first pattern 10 with a center 10 C, such as a fairly large box (e.g., 50 microns on a side), at a first location on the wafer. The wafer is then developed, and re-coated with photoresist and re-loaded into the machine. A second pattern 20 with a center 2 C, similar or identical to that of pattern 10 , is then printed on the wafer at a second location so that its center 20 C is precisely displayed from center 10 C by a predetermined distance (e.g., 200 microns). This displacement is accomplished by programming the machine to move either the wafer stage or reticle stage (or both) by the predetermined distance 30 (see FIG. 2 ). This “send ahead” wafer is then sent to an independent alignment measurement tool. The alignment measurement tool measures the precise location of centers 10 C and 20 C of patterns 10 and 20 , respectively, relative to some reference point. From this information, the measurement tool deduces the actual displacement 30 ′ between the respective centers. For a perfect machine, the measured displacement 30 would be identical to that of the programmed displacement 30 ′. However, with reference to FIG. 1B , in practical actual measured displacement 30 and programmed displacement 30 ′ are different. This different Δ represents the “alignment offset” for the particular combination of machine and job.
The alignment offset can be due to a number of factors, such as differences in viewing at the alignment wavelength of light (which is visible or near-visible) to the actinic light (typically ultraviolet), mechanical calibration, and the sensitivity of the pattern recognition software to the particular alignment pattern (“mark”) printed on the wafer. More generally stated, the alignment offset has a machine-dependent hardware contribution and a job-dependent pattern contribution. Thus, with reference to FIG. 2 , in order to perform a number of jobs (J 1 to Jn) on a number of different machines M 1 to Mn, a large number (n 2 ) of offset measurements OM 9 need to be performed (one measurement for each machine-job combination) to create a matrix of information relating each job to each machine.
It would be greatly advantageous to have a system for and method of calibrating a lithography system (“machine”) that allows a given process (“job”) to be run on any machine within a family of machines. A method and system for machine characterization that eliminates the need for time-consuming and costly send-ahead wafers would provide for much desired “job portability” in semiconductor manufacturing.
SUMMARY OF THE INVENTION
The present invention relates to alignment systems in optical apparatus, and in particular relates to a system and method for characterizing machine alignment offsets for lithography systems to provide for job portability between the lithography systems.
Accordingly, a first aspect of the invention is a method of measuring the machine alignment offset of an optical machine having an alignment system. The machine is the kind used to form overlayed images of first and second patterns formed on first and second reticles onto a substrate (e.g., a semiconductor wafer) at respective first and second levels. An example of such an optical machine is a lithographic system. The method comprises the steps of creating one or more virtual zero-offset alignment patterns and one or more virtual zero-offset metrology patterns. A virtual zero-offset pattern is an idealized pattern formed using, for example, a CAD program. The next step includes imaging with the optical machine, using first and second exposures, first and second metrology patterns onto the substrate at the first and second levels, respectively. The exposures are performed in an overlayed manner by aligning the second level to the first level using the zero-offset alignment patterns. The first and second metrology patterns are based on the one or more virtual zero-offset metrology patterns. For example, the first metrology pattern might be a square array of alignment patterns corresponding to the zero-offset pattern, while the second metrology pattern might be just the zero-offset pattern. The overlayed exposures might then consist of forming the second metrology pattern at a particular location (e.g., the center) within the first metrology pattern array. The next step then involves obtaining an image of the overlayed first and second metrology patterns formed on the substrate. The image is obtained using the alignment system of the optical machine. The next step is then comparing the virtual zero-offset metrology pattern (which is preferably stored in memory in an alignment system computer) to corresponding portions of the images obtained with the alignment system to deduce an offset relative to the ideal alignment of the first and second metrology patterns.
A second aspect of the invention is an alignment system capable of measuring a machine offset. The alignment system is preferably part of an optical machine having a machine optical system. The machine optical system is used to form overlayed images of first and second patterns formed on first and second reticles (or on the same reticle) onto a substrate at respective first and second levels. The alignment system comprises a light source and an alignment optical system arranged adjacent the light source. The alignment system is designed such that light from the light source is directed to illuminate a portion of the substrate and pass back through at least a portion of the alignment optical system. The alignment system further includes a detector, such as a CCD camera, capable of detecting images of first and second alignment patterns formed on the substrate at respective first and second levels and illuminated by the alignment system light source. The alignment system also includes a computer system having pattern recognition software stored therein and a memory unit containing one or more virtual zero-offset patterns accessible to the pattern recognition software. At least one of the one or more zero-offset patterns corresponds to the first and second metrology patterns. The computer system is capable of comparing images of the first and second metrology patterns detected by the alignment optical system to at least one of the one or more virtual zero-offset patterns. The first and second metrology patterns are formed on the substrate in an overlayed manner. The comparison is performed to determine the offset between the first and second metrology patterns relative to an ideal overlay of the first and second patterns.
A third aspect of the present invention includes a method of processing wafers in the manufacture of semiconductor devices using a set of two or more machines in a manner that is independent of the type of job being performed on the machine. The method includes the steps of measuring a machine alignment offset for each machine in the set of machines in the manner described briefly above and in more detail below. The next step is then storing the measured machine offsets in the corresponding machines. The next step involves creating zero-offset alignment patterns for each job. The next step then involves processing wafers on any machine in the set of machines without measuring an offset for any machine in the set of machines that depends on the job being performed. This is the “machine-independent” aspect of the present invention, since the performance of a particular job (i.e., the processing of wafers according to a particular recipe) does not depend on what machine in the set of machines is used. Furthermore, it is not necessary to measure the job dependent offset for any job.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a plan view of two metrology patterns printed on a wafer, the patterns displaced by a predetermined amount in the process of measuring overlay;
FIG. 1B is a vector diagram of the offset measured between the programmed displacement of the alignment patterns and the actual measured displacement between the alignment patterns;
FIG. 2 is a table that illustrates the matrix of offset measurements used in the prior art method of characterizing machines for different jobs to be carried out in the fabrication of a semiconductor device using different machines;
FIG. 3 is a schematic diagram of a lithography system, showing the alignment system and its components;
FIG. 4 is a flow diagram of the main method steps for characterizing machine offset according to the present invention;
FIG. 5 is a schematic diagram of a computer system having a database, a CAD design program and a memory;
FIG. 6 is a schematic diagram of examples of shape primitives included in the database of FIG. 5 ;
FIG. 7 is a flow diagram of the method steps for forming a digitized simulated image of a composite zero-offset pattern according to the present invention;
FIG. 8 is an example of a composite zero-offset pattern formed from four shape primitives;
FIG. 9 is a flow diagram of the method steps for measuring the machine offset using the zero-offset patterns of the present invention;
FIG. 10A is a schematic plan view of an exemplary metrology pattern for the first level formed from the composite zero-offset pattern;
FIG. 10B is a schematic plant view of the zero-offset pattern used to form the metrology pattern for the first level, and that serves as the metrology pattern for the second level that is aligned to the first level during overlay measurement;
FIG. 10C is a schematic plan view of the overlay of the first and second metrology patterns of FIG. 10 A and FIG. 10B , showing the machine offset that corresponds to the dislocation of the centers of the metrology patterns; and
FIG. 11 is a table that illustrates the matrix of offset measurements used in the present invention for characterizing each machine in a set of machines for different jobs to be carried out in the fabrication of a semiconductor device.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to alignment systems in optical apparatus, and in particular relates to a system and method for characterizing machine alignment offsets for lithography systems to provide for job portability between the lithography systems. The method and system of the present invention allows for the characterization of the machine or “hardware” offset by eliminating the pattern offset. The present invention is thus applicable for machines having an alignment system that utilizes a machine vision system and corresponding software, such as described in the '813 patent.
With reference now to FIG. 3 , there is a lithographic system 40 , such as the described in detail the '813 patent. System 40 includes, in order along an optical axis A, an illumination system IS that emits light of a select wavelength, a reticle stage RS for supporting a reticle R, a projection lens PL having an object plane and an image plane and arranged to receive light passing through reticle R, and a wafer stage WS. Reticle stage RS supports reticle R, which has formed thereon a pattern (not shown), in object plane OP so that it can be illuminated uniformly with the light from illumination system IS. Wafer stage WS supports a wafer W, coated with photosensitive material, in image plant IP so that an image of the pattern(s) on reticle R are properly formed on the wafer. The photosensitive material on wafer W is sensitive to the select wavelength of light from illumination system IS.
In optical communication with reticle R, projection lens PL and wafer W is an alignment system AS, shown attached to illumination system IS. Alignment system AS directs alignment light AL of a given wavelength (preferably a wavelength different than the exposure wavelength, e.g., 550 nm) from an alignment system light source 42 through reticle R, through projection lens PL, to wafer W, and back to the alignment system. Alignment system AS is thus a TTL system.
Alignment system AS further includes an alignment camera AC, such as a CCD camera, as a detector to detect alignment light AL reflected from wafer W and detected by the alignment system optics (not shown in detail). Alignment system AS also includes a computer system CS having stored therein, e.g., on a hard drive HD, pattern recognition software PRS for processing images of alignment marks imaged onto alignment camera AC by the alignment system optics. Computer system CS further includes a memory unit MU capable of storing information, such as alignment pattern images, to be used by pattern recognition software PRS. System 40 further includes a main control unit 46 electrically connected to illumination system IS, reticle stage RS, wafer stage WS, alignment system AS and computer system CS, for controlling the operation of system 40 , including controlling the process of aligning reticle R to wafer W prior to exposing the wafer with actinic light.
In the description below, the word “machine” refers to a lithographic system such as lithographic system 40 .
Method of Operation
With reference to the flow diagram 60 of FIG. 4 , the method of the present invention includes two main steps, each described in greater detail below. The first step 62 involves creating one or more “synthetic models.”A synthetic model is a “zero offset” pattern in a rectangular region (“box”), wherein the centroid (i.e., geometric center) of the box is the geometric center of the pattern. The second step 64 then involves performing a measurement of the component of the alignment offset attributable to the machine using the machine itself, rather than performing overlay measurements on a separate overlay measurement tool.
An additional step in the method of the present invention is step 66 of creating zero-offset alignment patterns for each job. This eliminates the requirement for determining the pattern offset for each job.
Synthetic Model Method
Step 62 involving the formation of zero offset patterns mentioned above in connection with flow diagram 60 of FIG. 4 , is now described in more detail with reference to FIGS. 5-8 .
With reference to FIG. 5 , the synthetic model of the present invention involves the use of computer system 90 having a pattern database 100 and a computer-aided design (CAD) program 110 that can access database 100 . Computer system 90 includes a memory 116 . Pattern database 100 stores a set (“palette”) of shape primitives 120 , such as 120 A- 120 D as shown in FIG. 6 , having defined geometric centers 122 A- 122 D, respectively.
With reference to FIG. 7 , step 62 A of the synthetic model method involves combining shape primitives 120 to form more complex shapes to be used as alignment patterns. An example alignment pattern formed from combining shape primitives 120 is pattern 130 of FIG. 8 , which made is up of four shape primitives 120 D, and which has a composite geometric center 132 . Pattern 130 is formed within a box 134 (dashed line) which also have a geometric center 136 coinciding with geometric center 132 . Shape primitives 120 can be overlapped, rotated, or have one or more of its dimensions increased in decreased. The centroid of the alignment pattern can be defined by the CAD program user. Also, the CAD program 110 preferably has the capability of generating and storing in database 100 additional user-defined shape primitives 120 , if necessary.
The CAD program 110 is designed with a graphical user interface, which allows the user to select shape primitives 120 and add them to a design sheet. For each element on the design sheet, the user can select features, such as dimensions, center or reference location, relative gray scale value, and edge width. The user also defines the size of box 134 that contains the pattern elements. Everything within box 134 will be used by pattern recognition software (PRS stored in computer system 90 to identify and locate a matching pattern on wafer W. Since the PRS defines the location of a matched pattern based on the box, not the shapes within the box, any separation between the center of the composite shape and the center of the box will register as an alignment offset (the pattern component). For this reason, it is necessary to design the synthetic model such that the geometric center of the composite pattern coincides with the center of the box (see FIG. 8 ).
The next step 62 B in the synthetic model method is digitizing the line-drawn composite alignment pattern to form a bit-map image of the pattern. This is accomplished by CAD software 110 , which is also used to define the scale of pixel size to physical size, i.e., the number of pixels per micron. A pattern edge that passes through a pixel (as opposed to corresponding to a pixel edge), is handled by using linear interpolation to obtain sub-pixel resolution of the alignment pattern. A typical pixel resolution for an alignment pattern is about 500 nm per pixel.
With continuing reference to FIG. 7 , the next step 62 C in the synthetic model method involves creating a simulated optical image of the bit-map image. This is achieved by convolving the bit-map image with the idealized lens optical transfer function (OTF) of the alignment system optics, a technique that is well understood in the art of optics. This step is performed in order to obtain an accurate representation of the alignment pattern image (referred to hereinafter as a “virtual alignment pattern”) as formed by the alignment optical system. This virtual alignment pattern is made accessible to the pattern recognition software PRS of the machine (e.g., via memory with MU). This approach of providing a virtual alignment pattern accessible to pattern recognition software PRS is in contrast to prior art methods. In the prior art methods, the pattern recognition software of the alignment system includes only “learned” patterns based on actual images of alignment patterns taken from wafers. The prior art approach results in the pattern recognition software having errors associated with the imaged pattern (which includes machine errors) built into it, thereby preventing the separation of the hardware and software components of the alignment offset.
In addition, a “learned” pattern will by necessity contain a pattern offset: the center of the pattern will not coincide exactly with the center of the box containing the pattern. In measuring alignment offsets on a machine, this pattern offset then becomes combined with the machine's hardware offset. In order to separate the machine offset from the pattern offset, it is necessary to use a zero-offset pattern. The next step 62 D involves optionally scaling or rotating the simulated optical image in X or Y to simulate process-induced changes, if such changes are known to occur. Such process-induced changes include scaling due to the application of successive layers of material on top of the initial target in the process of fabricating a device, or rotation of a target due to crystal growth occurring along preferred axes when crystalline layers are grown on the surface of the substrate.
The next step 62 E involves saving the simulated optical image as a file stored in memory 116 . At some point, this file is transferred to memory unit MU in computer system CS of the machine, so that it is accessible to pattern recognition software PRS.
Measuring Machine Offset
With reference now to FIG. 9 and flow diagram 64 therein, as well as FIGS. 10A-10C , in step 64 A the method described above for creating a synthetic model is used to create a zero-offset alignment pattern that represents the feature in the reticle for a first level (level 1 ) that will be printed on the wafer during the level 1 exposure, and will be used as the wafer target for aligning a second level (level 2 ) to level 1 .
In step 64 B, a second zero-offset pattern is created to represent the feature on the reticle for level 2 that will be used as a reticle key for aligning level 2 to level 1 .
Next, in step 64 C one or more zero-offset patterns are created to represent the features in the level 1 reticle and the level 2 reticle to be printed on the wafer on the first and second levels respectively, and to be used as the metrology patterns.
With reference now also to FIG. 10A , by way of example, a preferred metrology pattern arrangement 200 includes replicating a particular zero offset pattern 210 having a geometric center 212 ( FIG. 10B ) at four corners of an imaginary square 214 , as indicated by the dashed line. Metrology pattern 200 has geometric center 220 . In a preferred embodiment, the second metrology pattern is simply the single zero offset pattern that makes up part of the first metrology pattern.
Thus, in step 64 D, metrology pattern 200 is imaged onto the wafer on the first level, and the image developed to form the first level metrology pattern on the wafer. The wafer is then re-coated with a new layer of photoresist and is placed back into the machine.
In step 64 E, the level 2 reticle is aligned to the first level on the wafer using alignment system AS ( FIG. 3 ) such that the zero-offset alignment pattern for the target is used to locate the target on the wafer, and the zero-offset alignment pattern for the key is used to locate the key on the reticle. When the second level is then exposed on the wafer, the second metrology pattern arrangement is imaged relative to the first metrology pattern to form the composite metrology pattern on the wafer.
With reference to FIG. 10C , in a preferred embodiment, the second metrology pattern is printed so that its geometric center (e.g., center 212 ) is imaged to the geometric center (e.g., center 220 ) of the first metrology pattern.
Next, in step 64 F, the offset between the first-level and second-level metrology patterns is measured using the machine alignment system AS (FIG. 3 ). The amount of misalignment 250 between centers 212 and 220 corresponds to the alignment offset. In the present invention, because the second level is aligned to the first level using zero-offset alignment patterns, the misalignment between the first and second metrology pattern centers is entirely attributable to the machine offset. In the prior art method, the alignment offset includes both machine offsets and pattern offsets.
In the present invention, misalignment 250 is measured by alignment system AS of the machine itself, rather than removing the wafer from the machine and making the measurement on a separate metrology tool. This is possible because, in contrast to prior art systems where the alignment system has stored in its computer memory actual images of the patterns, the present invention loads zero-offset images into memory unit MU of alignment system AS. Thus, when alignment system camera AC detects the images of the first and second metrology patterns, the images are processed by pattern recognition software PRS, which then calculates an offset that does not include a component due to pattern offsets caused by the “learning” process. By creating zero-offset images as described above and making them available to the pattern recognition software, the offset that is ultimately measured is attributable to that caused only by the machine itself.
Strictly speaking, measuring the offset on the machine is used for convenience only, and is not required for job portability. However, measuring the offset on the machine does increase the reliability of the result since the machine calculates the offset and automatically stores it. In the prior art method, a user would have to take measurement results from another machine (like an alignment tool, such as those available from KLA-Tencor, San Jose, Calif.), manually calculate the proper offsets, and type them into the machine; a process which introduces many opportunities for error.
With continuing reference to FIG. 9 , in step 64 G, the measured machine offset is entered into main control unit 46 for future reference, so that when a particular job is run, the machine offset can be recalled and programmed into the machine so that the alignment is performed during a particular job with the machine offset accounted for.
Thus, with reference now to FIG. 11 , the present invention includes a method of processing wafers in manufacturing semiconductor devices in a manner that is “job portable.” This is accomplished by determining a set of machine offsets S MO ={MO 1 , MO 2 , . . . Mn} that includes the machine offset (MO) for a corresponding set S M ={M 1 , M 2 , . . . Mn}, of two or more machines M and storing the respective offsets in the corresponding machine, e.g., in memory unit MU ( FIG. 3 ) of each machine, as described above. Wafers corresponding to any one of a number of jobs J in a set of jobs S J ={J 1 , J 2 , . . . Jn} can then be run on any of the machines without having to measure a separate offset corresponding to a particular job J (see FIG. 2 ). Thus, the number of offset measurements needed to process wafers in manufacturing is thus reduced from n 2 to n using the method of the present invention.
To this point, the machine dependence from the jobs has been removed, i.e., any job can, in theory, get the same alignment result on any machine. However, one still needs to measure a job offset for each job, which will be the same for all machines. This results in n+m measurements for n machines and m jobs, unless step 66 ( FIG. 4 ) is included, i.e., creating zero-offset patterns for each job. This eliminates the requirement for determining the pattern offset for each job, and results in only having to make n measurements.
The many features and advantages of the present invention are apparent from the detailed specification, and, thus, it is intended by the appended claims to cover all such features and advantages of the described apparatus that follow the true spirit and scope of the invention. Furthermore, since numerous modifications and changes will readily occur to those of skill in the art, it is not desired to limit the invention to the exact construction and operation described herein. Accordingly, other embodiments are within the scope of the appended claims. | A method of measuring machine alignment offset of an optical machine having an alignment system, so that subsequent processing of substrates on set of optical machines can be performed in a machine-independent manner. The optical machine forms overlayed images of first and second patterns formed on either one or two reticles onto a substrate at respective first and second levels. The method of the invention includes forming a virtual zero-offset alignment pattern and a virtual zero-offset metrology pattern and imaging first and second metrology patterns on the substrate at the first and second levels, respectively. The second metrology pattern is aligned to the first metrology pattern using the zero-offset alignment pattern so that the exposures are performed in an overlayed manner. The first and second metrology patterns are based on the virtual zero-offset metrology pattern. An image of the overlayed first and second metrology patterns formed on the substrate is obtained using the alignment system of the optical machine. The virtual zero-offset metrology pattern is compared to corresponding portions of the image of the overlayed metrology patterns to deduce an offset from an idea alignment of the first and second metrology patterns. Zero-offset alignment patterns for one or more jobs may also be created so that the jobs can be run without an extra step of determining the job-dependent offset for each job. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application Ser. No. 10/671,354 filed on Sep. 25, 2003. The disclosure of the above application is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] Hydraulic dampers, such as shock absorbers, are used in connection with motor vehicle suspension systems to absorb unwanted vibrations which occur during the operation of the motor vehicle. The unwanted vibrations are dampened by shock absorbers which are generally connected between the sprung portion (i.e., the vehicle body) and the unsprung portion (i.e., the suspension) of the motor vehicle. A piston assembly is located within the compression chamber of the shock absorber and is usually connected to the body of the motor vehicle through a piston rod. The piston assembly includes a valving arrangement that is able to limit the flow of damping fluid within the compression chamber when the shock absorber is compressed or extended. As such, the shock absorber is able to generate a damping force which “smooths” or “dampens” the vibrations transmitted between the suspension and the vehicle body.
[0003] A prior art thermal expansion compensating twin tube shock absorber 100 is shown in FIG. 1 . Shock absorber 100 comprises an elongated pressure tube 102 provided for defining a hydraulic fluid containing compression chamber 104 and an elongated reserve tube 106 provided for defining a hydraulic fluid containing reservoir 108 .
[0004] Disposed within compression chamber 104 is a reciprocal piston assembly 110 that is secured to one end of an axially extending piston rod 112 . Piston rod 112 is supported and guided for movement within pressure tube 102 by means of a combination seal and rod guide assembly 114 located at the upper end of pressure tube 102 and having a centrally extending bore 116 through which piston rod 112 is reciprocally movable. Disposed within bore 116 between rod guide assembly 114 and piston rod 112 is a bushing 118 which is used to facilitate movement of piston rod 112 with respect to rod guide assembly 114 .
[0005] A compliant cylinder end assembly, generally designated at 120 , is located at the lower end of pressure tube 102 . The compliant cylinder end assembly 120 includes a base valve assembly 122 that functions to control the flow of hydraulic fluid between compression chamber 104 and fluid reservoir 108 as well as biasing member 124 that compensates for the differing axial thermal expansion between the various components of shock absorber 100 . Fluid reservoir 108 is defined as the space between the outer peripheral surface of pressure tube 102 and the inner peripheral surface of reserve tube 106 .
[0006] The upper and lower ends of shock absorber 100 are adapted for assembly into a motor vehicle. Piston rod 112 is shown having a threaded portion 126 for securing the upper end of shock absorber 100 to the motor vehicle while reserve tube 106 is shown incorporating a flange 128 having a pair of mounting holes 130 for securing the lower end of shock absorber 100 to the motor vehicle (McPherson strut configuration). While shock absorber 100 is shown in a McPherson strut configuration having threaded portion 126 and flange 128 for securing it between the sprung and unsprung portions of the motor vehicle, it is to be understood that this is merely exemplary in nature and is only intended to illustrate one type of system for securing shock absorber 100 to the motor vehicle. As will be appreciated by those skilled in the art, upon reciprocal movement of piston rod 112 and piston assembly 110 , hydraulic fluid with compression chamber 104 will be transferred between an upper portion 132 and a lower portion 134 of compression chamber 104 as well as between compression chamber 104 and fluid reservoir 108 through valve assembly 122 for damping relative movement between the sprung portion and the unsprung portion of the motor vehicle.
[0007] This quick exchange of hydraulic fluid through valve assembly 122 and piston assembly 110 as well as the friction between piston assembly 110 and pressure tube 102 and the friction between piston rod 112 and rode guide 114 generates heat which is undesirable during prolonged operating conditions.
[0008] In addition to absorbing the heat generated while providing the damping function for the motor vehicle, shock absorber 100 is also required to operate over a broad range of temperatures ranging from severe cold temperatures of the winter months to the extremely hot temperatures of the summer months. Prior art shock absorbers are manufactured using steel for pressure tube 102 and reserve tube 106 . While steel has been proven to be an acceptable material for these components, tubes manufactured from aluminum offer the advantages of weight savings as well as improved heat dissipation. If the typical pressure tube 102 were manufactured from steel while reservoir tube 106 were manufactured from aluminum, the difference in their relative axial thermal expansion rates may present problems for the shock absorber when operating over the necessary temperature extremes. Specifically, structural failure may occur under extreme cold temperatures or loss of pressure tube preload and sealing may occur under extreme hot temperatures.
[0009] Accordingly, continued development of shock absorbers with aluminum tubes includes the further development of methods to compensate for differing thermal expansion between aluminum and steel as well as the differing thermal expansion between any other two materials.
SUMMARY OF THE INVENTION
[0010] The present invention provides the art with a shock absorber which is capable of compensating for the differing thermal expansion between two materials and thus eliminating the possibility of structural failure due to extreme cold temperatures as well as the possibility of pressure tube preload loss and sealing failure under extreme hot temperatures.
[0011] In one embodiment of the present invention, the shock absorber includes a free floating pressure tube that is capable of compensating for differing thermal expansion by freely moving between the rod guide assembly and the valve assembly.
[0012] In another embodiment of the present invention, a unique piston rod is provided that includes an aluminum rod that eliminates the difference in thermal expansions. The rod has a steel cap that absorbs compression forces.
[0013] In another embodiment of the present invention, a unique compensating rod guide assembly is provided that includes a thermal compensation element capable of compensating for the differing thermal expansion between the pressure tube and the reserve tube.
[0014] In still another embodiment of the present invention, a unique compensating cylinder end assembly is provided that includes a thermal compensation element, and the means for securing the element to the valve assembly. This compensating element is either a spring, an elastomeric block, or gas pressure.
[0015] Other advantages and objects of the present invention will become apparent to those skilled in the art from the subsequent detailed description, appended claims and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In the drawings which illustrate the best mode presently contemplated for carrying out the present invention:
[0017] FIG. 1 is a longitudinal cross-sectional view through a prior art thermal expansion compensating shock absorber;
[0018] FIG. 2 is a longitudinal cross-sectional view of a shock absorber incorporating a floating pressure tube;
[0019] FIG. 3 is a side view of a unique aluminum piston rod with a steel cap;
[0020] FIG. 4 is an enlarged side view of a threaded steel cap;
[0021] FIG. 5 is an enlarged side view of a bonded steel cap;
[0022] FIG. 6 is an enlarged cross-sectional view of a compensating rod guide assembly with Belleville springs;
[0023] FIG. 7 is an enlarged cross-sectional view of a compensating rod guide assembly with a bearing bush retainer;
[0024] FIG. 8 is an enlarged cross-sectional view of an alternate compensating rod guide assembly with a bearing bush retainer;
[0025] FIG. 9 is an enlarged cross-sectional view of a compensating rod guide assembly with a retainer;
[0026] FIG. 10 is an enlarged cross-sectional view of a compensating cylinder end assembly with Belleville springs;
[0027] FIG. 11 is an enlarged cross-sectional view of the compensating cylinder end assembly of FIG. 10 illustrating a circle-clip and retainer support for the compensating member;
[0028] FIG. 12 is an enlarged cross-sectional view of the compensating cylinder end assembly of FIG. 10 illustrating a spring retainer for the compensating member;
[0029] FIG. 13 is an enlarged cross-sectional view of the compensating cylinder end assembly of FIG. 10 illustrating a double ring retainer for a compensating member;
[0030] FIG. 14 is an enlarged cross-sectional view of an alternate compensating cylinder end assembly having a two piece end assembly that sandwiches the compensating member;
[0031] FIG. 15 is an enlarged cross-sectional view of an alternate compensating cylinder end assembly illustrating the pressure tube and compensating member disposed within the valve assembly;
[0032] FIG. 16 is an enlarged cross-sectional view of a compensating cylinder end assembly with Belleville springs at the base;
[0033] FIG. 17 is an enlarged cross-sectional view of a compensating cylinder end assembly with an elastomeric block at the base;
[0034] FIG. 18 is an enlarged cross-sectional view of a compensating cylinder end assembly with gas pressure at the base; and
[0035] FIG. 19 is an enlarged cross-sectional view of an alternate compensating cylinder end assembly with gas pressure at the base.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0036] Continued reference is made generally to FIG. 1 and specifically to the components of shock absorber 100 throughout the subsequent description. It is to be understood that the construction of shock absorber 100 is merely exemplary in nature and is only intended to illustrate one type of hydraulic damping apparatus within which the compensating elements of the present invention can be utilized.
[0037] Referring now to the drawings in which like reference numerals designate like or corresponding parts throughout the several views, there is shown in FIG. 2 a unique compensating shock absorber 200 having a floating pressure tube 202 and a base valve assembly 222 . Rod guide assembly 114 and base valve assembly 222 are mechanically secured to reserve tube 106 . As the relative length of reserve tube 106 changes due to thermal conditions, the relative distance between rod guide assembly 114 and base valve assembly 222 changes. In the prior art, pressure tube 102 is fixed at one end to one portion of rod guide assembly 114 and at the other end to base valve assembly 122 , such that changes in the length of pressure tube 102 due to thermal conditions were compensated for using a multi-piece valve assembly 122 . In this embodiment of the present invention, a floating pressure tube 202 replaces pressure tube 102 of the prior art in order to compensate for the different thermal expansions of reserve tube 106 and floating pressure tube 202 . Floating pressure tube 202 is sealed to rod guide assembly 114 and base valve assembly 222 using O-rings 204 . Floating pressure tube 202 is able to move freely between rod guide assembly 114 and base valve assembly 222 as the relative length of reserve tube 106 changes. Thus, both a standard valve guide assembly and a standard base valve assembly can be easily modified to accept floating pressure tube 202 .
[0038] In another embodiment of prior art shock absorber 100 , a hybrid piston rod 312 replaces the prior art piston rod 112 as shown in FIGS. 3-5 . Typically the prior art piston rod 112 is made from steel while rod guide assembly 114 is made from aluminum. Under extreme thermal conditions the seal between piston rod 112 and rod guide 114 can be broken by the different thermal expansion of the two materials. Hybrid piston rod 312 includes an aluminum piston shaft 314 and a steel piston post 316 . As shown in FIG. 4 , piston post 316 includes an internal bore 318 which slidingly receives the end of piston shaft 314 . A circle-clip 320 retains the assembly of piston post 316 and piston shaft 316 . As shown in an alternative embodiment in FIG. 4 , piston post 316 has an open threaded bore 322 for receiving a threaded end of piston shaft 314 . Piston post 316 may be threaded on to piston shaft 314 . Alternatively, as seen in FIG. 5 , a modified steel piston post 330 with a flat end 332 may be adhesively secured to the end of piston shaft 314 . In operation, aluminum piston shaft 314 expands and contracts at the same rate as aluminum rod guide assembly 114 and thus prevents a break in the seal between the two. Steel piston post 316 , or alternately modified steel piston post 320 , absorbs the axial force on piston rod 312 when shock absorber 100 is in compression.
[0039] In still another embodiment of prior art shock absorber 100 , various compensating piston rod guide assemblies are shown in FIGS. 6-9 . The compensating piston rod guide assembly 414 , as shown in FIG. 6 , supports and guides the movement of piston rod 112 and also compensates for the different thermal expansion of pressure tube 102 and reserve tube 106 . Compensating piston rod guide assembly 414 includes bore 116 and bushing 118 , as well as a plurality, an even number in the preferred embodiment, of Belleville springs 424 disposed between rod guide 414 and pressure tube 102 . The difference in thermal expansion between steel pressure tube 102 and aluminum reserve tube 106 is compensated for by the increase or decrease in the compensation of Belleville springs 424 .
[0040] On the left side of FIG. 7 , an alternate compensating piston rod guide 414 ′ is shown. Alternate piston rod guide 414 ′ includes a bearing bush retainer 450 disposed between Belleville springs 424 and rod guide 414 ′. Bearing bush retainer 450 seals rod guide 414 ′ and pressure tube 102 and retains bushing 118 , and is further designed to support Belleville springs 424 . The thermal expansion of pressure tube 102 is directly compensated for by Belleville springs 424 . On the right side of FIG. 7 , piston rod guide 414 ′ is shown with bearing bush retainer 450 being replaced by compensation retainer 450 ′. Compensation retainer 450 ′ functions the same as bearing bush retainer 450 in that it retains bushing 118 and it is designed to support Belleville springs 424 . The thermal expansion is directly compensated for by Belleville springs 424 .
[0041] In another embodiment, a compensating piston rod guide 414 ″ is shown on the left side of FIG. 8 , wherein bearing bush retainer 452 is disposed between the pressure tube 102 and Belleville springs 424 . Bearing bush retainer 452 is similar to bearing bush retainer 450 in that it seals rod guide 414 ″ and pressure tube 102 and it supports Belleville springs 424 . The difference between bearing bush retainer 452 and 450 is that Belleville springs 424 are disposed between rod guide 414 ″ and bearing bush 452 instead of between bearing bush retainer 450 and pressure tube 102 as shown in FIG. 7 . The thermal expansion is directly compensated for by Belleville springs 424 . On the right side of FIG. 8 , piston rod guide 414 ″ is shown with bearing bush retainer 452 being replaced by compensation retainer 452 ′. Compensation retainer 450 ′ functions the same as bearing bush retainer 452 ′ in that it retains bushing 118 and it is designed to support Belleville springs 424 with Belleville springs 424 being disposed between rod guide 414 ″ and bush retainer 452 ′. The thermal expansion is directly compensated for by Belleville springs 424 .
[0042] In still another embodiment, a compensating piston rod guide 414 ′″ is shown in FIG. 9 , wherein bearing bush retainer 452 has been replaced by a compensation spring support 460 . Spring support 460 acts to support Belleville springs 424 but it does not retain bushing 118 . Belleville springs 424 are disposed between rod guide 414 ′″ and spring support 460 . The thermal expansion is directly compensated for by Belleville springs 424 .
[0043] In yet further embodiments of prior art shock absorber 100 , various compensating cylinder end assemblies are shown in FIGS. 10-19 . In FIG. 10 , a compensating cylinder end assembly, generally designated as 520 , is located at the lower end of pressure tube 102 and functions to control the flow of hydraulic fluid between compression chamber 104 and fluid reservoir 108 . Compensating end assembly 520 further acts to compensate for the differing axial thermal expansion between the various components of shock absorber 100 .
[0044] In FIG. 10 , compensating cylinder end assembly 520 includes a base valve assembly 522 and a plurality, an even number in the preferred embodiment, of Belleville springs 524 disposed between pressure tube 102 and base valve assembly 522 . The difference in thermal expansion between the steel pressure tube 102 and the aluminum reserve tube 106 is compensated for by the increase or decrease in the compression of Belleville springs 524 . This embodiment differs from the prior art shown in FIG. 1 by eliminating the need for the multi-piece base valve assembly 122 shown in FIG. 1 .
[0045] Various methods for securing Belleville springs 524 to an end assembly are shown in FIGS. 11-14 . In FIG. 11 , the compensating cylinder end assembly 520 ′ includes a reaction ring 550 . Reaction ring 550 is retained to the outside of pressure tube 102 by a circle-clip 552 . Belleville springs 524 are disposed between ring 550 and compression valve assembly 522 .
[0046] In FIG. 12 , a compensating cylinder end assembly 520 ″ includes an S-shaped spring retainer 560 . Spring retainer 560 is positioned between the bottom of pressure tube 102 and the top of Belleville springs 524 , and acts to retain Belleville springs 524 between spring retainer 560 and valve assembly 522 .
[0047] In FIG. 13 , the compensating cylinder end assembly 520 ′″ includes a first retaining ring 570 and a second retaining ring 572 . First retaining ring 570 is positioned such that it is in contact with the bottom of pressure tube 102 . Second retaining ring 572 is secured to valve assembly 522 . Belleville springs 524 are disposed between first retaining ring 570 and second retaining ring 572 .
[0048] In FIG. 14 , an alternate compensating cylinder end base valve assembly is designated at 620 . Compensating end base valve assembly 620 is divided into two portions, an upper portion 650 and a lower portion 652 , and includes a plurality of Belleville springs 624 disposed between the two portions 650 and 652 . Upper portion 650 is connected to pressure tube 102 and lower portion 652 is connected to or abuts reserve tube 106 . Upper portion 650 fits within lower portion 652 and is sealed by an O-ring 654 . Belleville springs 624 are disposed between the two portions 650 , 652 and act to compensate for the different thermal expansion of pressure tube 102 and reserve tube 106 by moving upper portion 650 and lower portion 652 towards or away from each other.
[0049] In FIG. 15 , an alternate compensating cylinder end assembly is designated at 720 . Cylinder end assembly 720 includes a base valve assembly 722 having a cylindrical wall 750 and a plurality of Belleville springs 724 . Cylindrical wall 750 is connected to and surrounds a base valve assembly 722 and further extends towards the opposite end of shock absorber 100 . Pressure tube 102 slides within cylindrical wall 750 , and is sealed by an O-ring 752 . Belleville springs 724 are disposed between pressure tube 102 and valve assembly 722 within cylindrical wall 750 .
[0050] In another embodiment of shock absorber 100 , compensating cylinder end assembly 820 is shown in FIG. 16 . Compensating end assembly 820 includes a base valve assembly 822 , a plurality of Belleville springs 824 , a base plate 850 , an O-ring 852 , and a bottom retainer 854 . Base plate 850 is capable of moving axially and is sealed to reserve tube 106 by O-ring 852 . Bottom retainer 854 is fixed to reserve tube 106 using a retaining ring 856 and provides a flat, stable bottom for cylinder end assembly 820 . Belleville springs 824 , an even number in the preferred embodiment, are disposed between base plate 850 and bottom retainer 854 . Belleville springs 824 act to compensate for the different thermal expansion of the various components of shock absorber 100 through base plate 850 and bottom retainer 854 . In an alternate cylinder end assembly 820 ′, as shown in FIG. 17 , Belleville springs 824 are replaced with an elastomeric block 860 . Elastomeric block 860 is disposed between base plate 850 and bottom retainer 854 and compensates for the different thermal expansion of pressure tube 102 and reserve tube 106 by expanding or compressing as necessary.
[0051] In compressing cylinder end assembly 920 , which includes a base valve assembly 922 as shown in FIG. 18 , pressurized gas 950 , for example compressed air, is disposed between a base plate 952 and a bottom retainer 954 . Bottom retainer 954 is sealed to reserve tube 106 by a weld 956 or other means known in the art such that the gas 950 remains pressurized. Pressurized gas 950 compensates for the different thermal expansion of pressure tube 102 and reserve tube 106 by expanding or compressing as necessary, and also reduces the weight of the shock absorber. In alternate cylinder end assembly 920 ′ as shown in FIG. 19 , bottom retainer 954 has been removed. Pressurized gas 950 is disposed between base plate 952 and reserve tube 106 and compensates directly for the different thermal expansion of the pressure tube 102 and the reserve tube 106 .
[0052] While the above detailed description describes the preferred embodiment of the present invention, it should be understood that the present invention is susceptible to modification, variation and alteration without deviating from the scope and fair meaning of the subjoined claims. | The present invention provides the art with a shock absorber which is capable of compensating for the differing thermal expansion between two materials. The shock absorber in its various embodiments includes a free floating pressure tube that is able to expand or contract axially without breaking a seal, a hybrid piston rod with a shaft of one material that compensates for differing thermal expansions and a cap of another material that absorbs axial forces, a unique rod guide assembly with a biasing member that compensates for differing thermal expansions, and a unique cylinder end assembly with a biasing member made from springs, a rubber block, or pressurized gas. | 5 |
FIELD OF THE INVENTION
The present invention relates to an offset rotary printing press. The offset rotary printing press has at least two printing units. Each such printing unit has at least one forme cylinder and one transfer cylinder. The cylinders are supported inside frames and the cylinders of a first one of the printing units is pivoted by 180° with respect to the second printing unit.
DESCRIPTION OF THE PRIOR ART
A rotary offset printing press in a satellite construction is known from DE-GM 73 22 211. Here, a web of material, for example, is printed by a ten cylinder printing unit and a nine cylinder printing unit. It is not disclosed to let the ten cylinder printing unit produce as a nine cylinder printing unit.
The reference manual “Rollenoffset, Technik, Systeme, Maschinen”Cylinder Offset, Technology, Systems, Presses, Oscar Frei, Polygraph, publ., 1979, discloses, on page 10, a combination of two five cylinder satellite printing units.
DE 43 03 904 A1 and DE 19 24 455 A1 both disclose printing units whose cylinders are arranged in the form of a letter “W”.
EP 0 638 419 A1 describes a printing press, wherein printing units are fastened on a support frame. Individual modular units, such as ink units or cylinder groups, for example, can be displaced in the direction of the cylinder axes.
DE 34 46 619 A1 shows a printing press, in which two movable groups of presses are described. However, these groups are only provided with four plate cylinders, to each of which an ink and dampening unit is assigned. Rubber blanket cylinders and counter-pressure cylinders are installed in a stationary press group.
SUMMARY OF THE INVENTION
The present invention is based on the object of creating an offset rotary printing press.
This object is attained in accordance with the invention by [means of the characteristics of claim 1 .] providing the offset rotary printing press with at least two printing units. The cylinders of one of the printing units are arranged pivoted by 180° in respect to the cylinders of the second printing unit. The drives for the cylinders are also pivoted by 180° in the first printing unit with respect to the second printing unit.
It is possible, in an advantageous manner, to perform a plurality of types of production by use of the printing units of the invention. For example, two five cylinder printing units can produce either individually or can produce together as a ten cylinder printing unit. In particular, two five cylinder printing units, each with different cylinder arrangements, can be used as a nine cylinder printing unit. The modular construction of the present invention permits the identical arrangement of the printing units; the modular construction kit consists of only two basic elements.
Here, the modular units can be combined in two ways. In a first way, one modular unit operates as an individual printing unit independently of a second one, while in a second way, two modular units are combined into a common printing unit. A placement reversed by 180°, with a shifting of the drive mechanism side and the operating side, is also possible. Thus, the drive mechanisms for the printing units are not arranged on a single side of the printing press. Instead, the drive mechanisms remain fixedly assigned to a lateral frame.
The ink systems also remain the same. A reversal of the direction of rotation is not necessary, since the combination of the modular units and their flexible assignment make possible 4/4, 4/2, 2/4 and 2/2 production requirements. Because of the possibility of movable printing units, operation from the inside is possible. This operation from inside is advantageous with “W” printing units in particular, because no release devices are therefore necessary.
By means of displaceable printing units, it is also possible to produce, by means of spaced-apart five cylinder printing units, as well as with two coupled five cylinder printing units, wherein respectively different types of production are possible.
If only a 4/2 or 2/4 production is desired, no “empty frames” of a satellite printing unit are necessary, since it is possible to arrange a singly arranged five cylinder printing unit to operate together with a four-color-producing satellite printing unit (ten or nine cylinder printing unit).
The placement of work platforms which can be raised and lowered in the intermediate frames and at the modular cylinder units makes the easy operation of the printing units possible.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention are represented in the drawings and will be described in greater detail in what follows.
Shown are in:
FIGS. 1 and 2, a schematic representation of the V- and W- printing units,
FIG. 3, a schematic representation of a lateral view of printing units in a first type of production,
FIG. 4, the schematic representation of a lateral view of printing units in a second type of production, and in
FIG. 5, a schematic top plan view on a bridge printing unit in modular construction.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
An offset rotary printing press, or a section of an offset rotary printing press has, for example, eight printing units 01 to 04 , 06 to 09 in modular construction, as seen in FIGS. 3 and 4. Each one of these printing units 01 to 04 , 06 to 09 is designed as a so-called five cylinder printing unit and essentially has two forme cylinders 11 to 14 , for example plate cylinders, two transfer cylinders 16 to 19 , for example rubber blanket cylinders, and one counter-pressure cylinder 21 , 22 or satellite cylinder. Journals of these forme or plate cylinders 11 to 14 , transfer or blanket cylinders 16 to 19 , and counter-pressure cylinders 21 , 22 are seated on each side of the offset rotary printing press in respectively one lateral frame 23 , 24 . In the present preferred embodiment, the journals of the transfer cylinders 16 to 19 are pivotably seated in eccentric bushings or by means of three-ring bearing technology, so that the transfer cylinders 16 to 19 can be placed against or removed from the associated counter-pressure cylinders 21 , 22 and/or forme cylinders 11 to 14 .
It is also possible to place the counter-pressure cylinders 21 , 22 against the associated transfer cylinders 16 to 19 by means of eccentric bushings, three-ring bearings or linear guidance, for example.
In the present preferred embodiment, each cylinder 11 to 14 , 16 to 19 , 21 , 22 is provided with its own rpm-controlled and/or its own position-controlled drive motor.
It is also possible to assign a drive motor to each pair of forme and transfer cylinders 11 , 16 ; 12 , 17 ; 13 , 18 ; or 14 , 19 , and to connect this pair in an interlocking manner. In this case, the counter-pressure cylinder 21 , 22 also has its own drive motor, or can be coupled to one of these pairs of forme and transfer cylinders 11 , 16 ; 12 , 17 ; 13 , 18 ; or 14 , 19 .
It is also possible to assign only one drive motor to each printing unit 01 to 04 , 06 to 09 .
In every case, the drive motors are each fixedly arranged in a lateral frame 23 , 24 , independently of the position and location of placement of the printing units 01 to 04 , 06 to 09 , so that with the printing units 06 to 09 , which units 08 and 09 have been placed pivoted by 180° around a vertical line with respect to units 06 and 07 , the drive motors for the printing units 06 to 09 , which are placed pivoted in respect to each other, are arranged on opposite sides SI, SII, as seen in FIG. 5, of the printing press. The drive motors of a printing unit 01 to 04 , 06 to 09 can also be arranged distributed over both lateral frames 23 , 24 . For example, the drive motors for the counter-pressure cylinders 21 , 22 and the forme cylinders 11 to 14 are arranged on the first lateral frame 23 , 24 , and the drive motors for the transfer cylinders 16 to 19 on the second lateral frame 23 , 24 . Here, too, the assignment of the drive motors to the respective lateral frame 23 , 24 , in case of a pivoted placement of the printing units 06 to 09 , remains within the printing press, or within a section of the printing press.
This assignment of the drive motors to a lateral frame in case of a pivoted placement of the printing units 06 to 09 within the printing press, or a section of the printing press, is also possible with other printing units in modular construction. Thus, a bridge printing unit 71 as seen in FIG. 5, can also be formed, for example, from two modular units 72 , 73 , each with a pair of forme and transfer cylinders 74 , 76 , wherein one modular unit 72 is arranged pivoted around a vertical line by 180° in respect to the other modular unit 73 . Respectively, one pair of forme and transfer cylinders 74 , 76 is seated in a pair of lateral frames 81 , 87 . In this case, one pair of the forme and transfer cylinders 74 , 76 is interlockingly connected via gear wheels 77 , 78 for being driven of a drive motor 79 . During printing operations, the two pairs are not interlockingly coupled with each other. This drive motor 79 is fixedly assigned to a lateral frame 81 .
With at least two printing units arranged inside a printing press, at least their cylinders and their lateral frames, as well as drive means, for example gears, gear wheels, drive motor assigned to the respective lateral frame or the respective cylinder, are arranged pivoted around a vertical line.
Respectively, one ink unit 26 to 29 and one dampening unit 31 to 34 are assigned to each forme cylinder 11 to 14 , wherein the dampening unit 31 to 34 is arranged upstream of the ink unit 26 to 29 in respect to the production direction of the forme cylinder 11 to 14 .
In connection with a first type of printing unit 02 , 04 , 07 , 09 , a straight first line 41 , or 42 , determined by an axis of rotation 37 of the counter-pressure cylinder 22 and an axis of rotation 38 , 39 of an associated transfer cylinder 16 , 17 , and a straight second line 46 , 47 determined by an axis of rotation 38 , 39 of the transfer cylinder 16 , 17 and an axis of rotation 43 , 44 of the forme cylinder 11 , 12 , enclose an opening angle α in a range between 150° to 210°, preferably 170° to 190°. The straight first line 41 determined by the axis of rotation 38 of the first transfer cylinder 16 and the axis of rotation 37 of the counter-pressure cylinder 22 encloses an opening angle β in the range between 60° to 120°, preferably 70° to 90°, with the corresponding straight first line 42 determined by the axis of rotation 39 of the second transfer cylinder 17 and the axis of rotation 37 of the counter-pressure cylinder 22 . The cylinders 11 , 12 , 16 , 17 , 22 of the printing units 02 , 04 , 07 , 09 of the first type are arranged in a so-called “V” arrangement, all as seen most clearly in FIG. 2 at the left thereof.
A washing device 36 , for example, can be selectively placed against the transfer cylinders 16 to 19 and/or the counter-pressure cylinders 21 , 22 .
The tight cylinder arrangement of the V-printing unit 02 , 04 , 07 , 09 makes it possible to simultaneously clean two cylinders with one washing device 36 .
In connection with a second type of printing unit 01 , 03 , 06 , 08 , as seen at the right side of FIG. 2, a first straight line 52 , 53 determined by an axis of rotation 48 of the counter-pressure cylinder 21 and an axis of rotation 49 , 51 of an associated transfer cylinder 18 , 19 , and a second straight line 57 , 58 , determined by an axis of rotation 49 , 51 of the transfer cylinder 18 , 19 and an axis of rotation 54 , 56 of the forme cylinder 13 , 14 , enclose an opening angle δ in a range between 90° to 120°, preferably 85° to 100°. The first straight line 52 determined by the axis of rotation 49 of the first transfer cylinder 18 and the axis of rotation 48 of the counter-pressure cylinder 21 encloses an opening angle γ, in the range between 60° to 120°, preferably 60° to 90°, with a straight line 53 determined by the axis of rotation 51 of the second transfer cylinder 19 and the axis of rotation 48 of the counter-pressure cylinder 21 . The cylinders 13 , 14 , 18 , 19 , 21 of the printing units 01 , 03 , 06 , 08 of the second type are arranged in a so-called “W” arrangement again, all as seen at the right side of FIG. 2 .
In the present preferred embodiment, respectively one printing unit 02 , 04 , 07 , 09 , in a “V” arrangement, and one printing unit 01 , 03 , 06 , 08 , in a “W” arrangement, are arranged opposite each other as shown in FIGS. 1-4. In this case, the axes of rotation 37 , 48 of the counter-pressure cylinders 21 , 22 are located on the same side in relation to a straight line determined by the axes of rotation 38 , 39 , 49 , 51 of the transfer cylinders 18 , 19 , 16 , 17 . With the printing units 01 to 04 of the upper level, all counter-pressure cylinders 21 , 22 are located to the right of the associated transfer cylinders 16 , 17 , 18 , 19 . With the printing units 06 to 09 of the lower level all counter-pressure cylinders 21 , 22 are located to the left of the associated transfer cylinders 16 , 17 , 18 , 19 . This is shown most clearly in FIG. 3 .
With the “W” printing units 01 , 03 , 06 , 08 , the counter-pressure cylinders 21 are located on the outside, with the “V” printing units 02 , 04 , 07 , 09 the counter-pressure cylinders 22 are located on the inside. With the printing press in accordance with the preferred embodiment, respectively one printing unit 01 , 03 , 06 , 08 in a “W” arrangement and one printing unit 02 , 04 , 07 , 09 in a “V” arrangement are arranged on top of each other.
The respective cooperatively positioned printing units 01 , 02 , or 03 , 04 , or 06 , 07 , or 08 , 09 can each be operated independently of each other as five cylinder printing units located opposite each other, i.e. in a first mode of operation, each two printing units 01 , 02 , or 03 , 04 , or 06 , 07 , or 08 , 09 located opposite each other functionally constitute a ten cylinder satellite printing unit as seen at the right in FIG. 3 . During this first operational state, the transfer cylinders 16 , 17 , or 18 , 19 operate together with the respective counter-pressure cylinders 22 or 21 of the “V” printing unit 02 , 04 , 07 , 09 and “W” printing unit 01 , 03 , 06 , 08 . In a second mode of operation, two five cylinder printing units functionally act as a nine cylinder satellite printing unit, as seen at the left side of FIG. 3 . To this end, the transfer cylinders 16 , 17 , 18 , 19 of a “V” printing unit 04 , 07 and a “W” printing unit 03 , 06 can be placed against or away from the counter-pressure cylinder 22 of the “V” printing unit 04 , 07 . The counter-pressure cylinder 21 of the “W” printing unit does not take part in the printing process.
In the present preferred embodiment, respectively one “V” printing unit 02 , 04 , 07 , 09 and a “W” printing unit 01 , 03 , 06 , 08 can be moved in relation to each other, thus providing a distance “a” between the “V” printing unit 02 , 04 , 07 , 09 and the “W” printing unit 01 , 03 , 06 , 08 , which distance “a” can be changed. To this end, the “V” printing unit 02 , 04 , 07 , 09 , for example, is arranged stationary, and the “W” printing unit 01 , 03 , 06 , 08 can be horizontally displaced, again as seen at the right in FIG. 3 .
Two associated “V” and “W” printing units 01 , 02 , or 03 , 04 , or 08 , 09 are at a distance “a” from each other particularly for being operated and serviced by an operator, so that the resulting space between the two printing units 01 , 02 , or 03 , 04 , or 08 , 09 becomes accessible. A work platform 59 is selectively arranged in this space. This work platform 59 can preferably be raised and lowered.
The operation and servicing of the ink units 26 to 29 takes place from the same side in the case of two associated printing units 01 , 02 , or 03 , 04 , or 06 , 07 or 08 , 09 . Therefore, the ink ducts 61 , for example, of the ink units 26 to 29 of both printing units 01 , 02 , or 03 , 04 , or 06 , 07 are oriented to one side, i.e. on the upper level the ink ducts 61 are oriented pointing toward the left, and on the lower level they are oriented pointing toward the right, as shown in both FIGS. 3 and 4.
The advantage here is that all ink ducts can be designed in the same way.
In a first mode of production which is depicted in FIG. 3, the left printing units 03 , 04 , 06 , 07 of the upper and lower levels are brought together and are coupled with each other. Thus, two nine cylinder printing units, stacked on top of each other, are formed. With each one of these two nine cylinder printing units the transfer cylinders 16 to 19 of the “V” and “W” printing unit 03 , 04 , or 06 , 07 have been placed against the counter-pressure cylinder 22 of the adjacent “V” printing unit 04 or 07 .
A web of material 62 is conducted on the counter-pressure cylinder 22 of the lower left “V” printing unit 07 by means of guide rollers 63 between the two stacked nine cylinder printing units from above between the two upper ink units 26 , 28 of the “V” and the “W” printing units 07 , 06 . This web of material 62 is looped around the counter-pressure cylinder 22 and is conducted upward between the two upper ink units 26 , 28 of the lower “V” and the “W” printing units 07 , 06 and then out of the lower nine cylinder printing unit diagonally upward onto the counter-pressure cylinder 22 of the upper “V” printing unit 04 .
In the upper nine cylinder printing unit, the web of material 62 also is looped around the counter-pressure cylinder 22 of the upper “V” printing unit 04 and is conducted downward out of the upper nine cylinder printing unit between the two lower ink ducts 27 , 29 of the upper “V” and “W” printing unit 04 , 03 .
The web of material 62 can also be introduced first at the top and then on the bottom.
A first side of the web of material 62 is printed in four colors in the lower nine cylinder printing unit, and a second side of the web of material 62 is printed in four colors in the upper nine cylinder printing unit.
In accordance with a second mode of production, as seen in the right side of FIG. 3, the respectively two right printing units 01 , 02 , or 08 , 09 , of the upper and lower levels are spaced apart from each other and are therefore not coupled.
Here, a web of material 64 coming from below is fed from the outside between the lower forme cylinder 14 and the counter-pressure cylinder 21 to the counter-pressure cylinder 21 of the lower “W” printing unit 08 . This web of material 64 is looped around the counter-pressure cylinder 21 over approximately 180° and is moved out of the “W” printing unit 08 toward the exterior between the upper forme cylinder 13 and the counter-pressure cylinder 21 . This web of material 64 is then fed, via guide rollers 63 between the upper right “V” and “W” printing units 01 , 02 , to the counter-pressure cylinder 22 of the upper “V” printing unit 02 , where web 64 is looped around the counter-pressure cylinder 22 over approximately 80° and is then conducted out of the upper “V” printing unit 02 between the upper right “V” and “W” printing units 02 , 01 .
A first side of the web of material 64 is printed in two colors in the lower “W” printing unit 08 , and a second side of the web of material 64 is printed in two colors in the upper “V” printing unit 02 .
A further web of material 66 coming from below is fed via guide rollers 63 between the lower right “V” and “W” printing units 09 , 08 , to the counter-pressure cylinder 22 of the lower “V” printing unit 09 . Web 66 is looped around this counter-pressure cylinder 22 over approximately 80° and is removed from the lower “V” printing unit 9 between the lower right “V” and “W” printing units 09 , 08 .
This web of material 66 is then fed between the lower forme cylinder 14 and counter-pressure cylinder 21 of the upper “W” unit 01 to the counter-pressure cylinder 21 of the upper “W” printing unit 01 . The web of material 66 is looped around the counter-pressure cylinder 21 over approximately 180° and is moved out of the “W” printing unit 01 toward the exterior between the upper forme cylinder 13 and the counter-pressure cylinder 21 .
A first side of the web of material 66 is printed in two colors in the lower “V” printing unit 09 , and a second side of the web of material 66 is printed in two colors in the upper “W” printing unit 01 .
In a third mode of production, which is shown in FIG. 4, the two left printing units 03 , 04 of the upper level are spaced apart from each other and therefore are not coupled, and the two left printing units 06 , 07 of the lower level are coupled to form a nine cylinder printing unit. The two right printing units 01 , 02 of the upper level are coupled to form a nine cylinder printing unit, and the two right printing units 08 , 09 of the lower level are spaced apart from each other.
A web of material 67 is conducted, by means of guide rollers 63 between the upper and lower levels, from the top between the two ink units 26 , 28 of the “V” and “W” printing units 07 , 08 on the counter-pressure cylinder 22 of the lower “V” printing unit 07 . This web of material 67 is looped around the counter-pressure cylinder 22 of the “V” printing unit 07 and is conducted between the two upper ink units 26 , 28 of the lower “V” and “W” printing units 07 , 06 out of the lower nine cylinder printing unit diagonally upward over guide rollers 63 between the upper left “V” and “W” printing units 04 , 03 on the counter-pressure cylinder 22 of the upper “V” printing unit 04 .
This web of material 67 is looped around this counter-pressure cylinder 22 over approximately 80° and is moved out of the upper “V” printing unit 04 inside between the upper left “V” and “W” printing cylinders 04 , 03 .
A first side of the web of material 67 is printed in four colors in the lower nine cylinder printing unit, and a second side of the web of material 67 is printed in two colors in the upper “V” printing unit 04 .
A web of material 68 , coming from below, is fed from the exterior between the lower forme cylinder 14 and the counter-pressure cylinder 21 to the counter pressure cylinder 21 of the lower right “W” printing unit 08 . This web of material 68 is looped around the counter-pressure cylinder 21 over approximately 180° and is removed toward the outside out of the lower right “W” printing unit 08 between the upper forme cylinder 13 and the counter-pressure cylinder 21 . This web of material 68 , which is fed over guide rollers 63 from the outside between the lower forme cylinder 14 and the counter-pressure cylinder 21 can then be directed to the counter-pressure cylinder 21 of the left upper “W” printing unit 03 , where it is looped around cylinder 21 of unit 03 over approximately 180° and is removed toward the exterior between the upper forme cylinder 13 and the counter-pressure cylinder 21 out of the upper left “W” printing unit 03 .
In the course of this, a first side of the web of material 68 is printed in two colors in the lower right “W” printing unit 08 , and a second side of the web of material is printed in two colors in the upper left “W” printing unit 03 .
A further web of material 69 is printed correspondingly to the first web of material 67 in a nine cylinder printing unit consisting of the upper right “V” and “W” printing units 02 , 01 , and in the lower right “V” printing unit 09 . In the course of this, a first side of the web of material 69 is printed in two colors in the lower right “V” printing unit 09 . Subsequently, a second side of the web of material 69 is printed in four colors in the upper nine cylinder printing unit.
The “V” and “W” printing units 01 to 04 , 06 to 09 , can be used as imprinters, i.e. while at least one pair of forme and transfer cylinders are placed against the counter-pressure cylinder for printing a web of material, at least one forme cylinder can be moved away for set-up purposes.
The printing units 01 to 04 , 06 to 09 in modular construction are arranged in a support device. This support device or consists, for example, of three transverse supports 82 , 83 , 84 , as seen in FIGS. 3 and 4, and which are arranged spaced apart from each other one above the other by means of vertically extending supports 86 . The printing units 01 to 04 , 06 to 09 are fastened to this support device or frame. With printing units 01 to 04 , and 06 to 09 arranged on top of each other, i.e. on two levels, the upper printing units 01 to 04 are fastened on a transverse support 83 , 84 or a support 86 of the support device. This transverse support 83 , 84 is arranged above the lower printing unit 06 to 09 . The transverse supports 82 to 84 can be divided into individual segments.
While preferred embodiments of a rotary offset printing machine in accordance with the present invention have been set forth fully and completely hereinabove, it will be apparent to one of skill in the art that various changes in, for example, the type of material web being printed on, the specific drive motors for the various cylinders and the like could be made without departing from the true spirit and scope of the present invention which is accordingly to be limited only by the following claims. | A rotary offset printing machine uses a plurality of printing units placed inversely by 180° with respect to a vertical line with respect to each other. The drive assemblies for the cylinders of the inversely placed two printing units are also inversely disposed. | 1 |
BACKGROUND OF THE INVENTION
The invention is in the field of structures, and relates particularly to a dome or partial dome structure having a unique construction. The invention also encompasses a method for forming and assembling the dome structure.
Domes or dome-like structures are disclosed in prior (Krieg) U.S. Pat. No. 765,017, (Moss) 3,562,975, (Davis) U.S. Pat. No. 4,067,153 and (Wolde-Tinase) U.S. Pat. No. 4,400,927. These disclosures are pertinent to the present invention in that they describe various methods for constructing domes, but none discloses or contemplates the particularly advantages method and structure of the invention. The Krieg, Davis and Wolde-Tinase patents all involve structural ribs or circumferential beams which support separate surface members or skin.
The Moss patent is pertinent to this invention in that it describes a dome-like shelter with segments or panels which serve as structural elements in the support of the completed shelter. However, the panels in the Moss structure are flexible, manufactured flat and stressed into a bowed configuration upon erection. The edges of adjacent panels are not butted together or overlapped and secured together, and the edges are not complimentarily fitted. Rather, the adjacent panels are connected by separate flexible joint devices assembled to the panel edges upon erection of the shelter. Moss' structure has an entrance way interrupting the circumference of the dome and eliminating several segments. The highly stressed erected configuration of the Moss shelter, which contributes to structural stability, contrasts sharply with the dome structure of the present invention and underlies the different principles of support involved in the two dome configurations.
SUMMARY OF THE INVENTION
The dome structure according to the present invention avoids structural ribs, circumferential bands, special joints and interior structural members. Its multiplicity of edge-connected segments serve as a skin or surface and also as structural supports acting together to give the dome rigidity and strength. Requiring no separate joint connector devices, the edges of the adjacent segments are abutted or complimentarily fitted directly together. They may include splines fitted into grooves of the adjacent edges, or other grooved or lapped edge joining structure, glued together.
The dome or partial dome according to the invention preferably is a part of a sphere, with arcuate segments, but true arcuateness is not essential, and each segment can be, for example, a portion of an ellipse.
Each segment tapers from a maximum width at its base end to a minimum width at the apex end, which may come to a point or may be truncated, to form a circular opening at the apex or tip of the assembled dome structure.
At the joints between adjacent segments, the edges are connected directly to each other, being complementary shaped as mentioned above. This involves a change in edge angle from the base end to the apex. The angle between edge and face varies from a maximum deviation off perpendicular at the base end to near-perpendicularity at the apex end. The method of the invention includes a special procedure and system for shaping the edges to fit together in this way.
The dome structure in a preferred embodiment is of wood, with each segment pre-shaped to the arcuate configuration it will have in the assembled dome. The segments may be formed of glued laminated wooden layers. The outer layer or layers may be of weather-resistant wood, with the inner layers of other less costly varieties of wood. However, the principles of the invention apply to other materials as well.
A circular or arcuate reinforcing ring may be secured to the base ends of the segments to add circular integrity and for edge finishing at the base but not for structurally connecting the segments together in edge-to-edge position. Similarly, a ring may be secured at the apex ends of the segments if the dome's apex is open.
The number of segments forming the dome structure may vary from a minimum of about 18 to 100 or even more. In one preferred embodiment about 90 segments are used, requiring the segments to effect a 4° turn from segment to segment at the linear base ends. This can be accomplished with equal 2° deviations from perpendicular at both edges of each segment's base end, continuously varying to near-zero deviation at the apex end.
Dome-like structures which are not full hemispheres are within the principles of the invention. These may include shapes not truly arcuate from base to apex, half domes or other portions of domes, domes with apex openings or side openings, and other variations which still take advantage of the structural principles of the invention. A full sphere can be produced from two hemispherical domes in accordance with the invention.
Accordingly, it is among the objects of the invention to produce a dome-like structure which is simple and elegant in construction, comprising a multiplicity of edge-connected segments which give structural integrity as well as providing inner and outer surfaces, and without additional structural members between the base and apex ends of the segments. These and other objects, advantages and features of the invention will be apparent from the following description of a preferred embodiment, considered along with the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of one embodiment of a dome structure constructed in accordance with principles of the invention.
FIG. 2 is a sectional view of the dome structure shown in FIG. 1.
FIG. 3 is a sectional plan detail view showing an example of a laminated construction of the segments and one joint configuration for joining adjacent segment edges.
FIG. 4 is a perspective view showing one preferred configuration of edges and the base end of a segment.
FIG. 5 is a partial plan view showing an open top or apex end of a dome, reinforced with a ring.
FIG. 6 is a perspective view showing one curved segment which may form a part of the dome structure of the invention.
FIG. 7 is a schematic view in perspective view, showing a method of the invention for forming segment edges so as to be complimentary to adjacent edges in the assembled dome.
FIG. 8 is a schematic perspective view indicating layup of the segments in assembly of the dome.
FIG. 9 is a partial view of a segment, in section, indicating connection to a bottom or base end ring which reinforces the base end of the assembled dome.
FIG. 10 is a partial sectional view similar to FIG. 9, but showing connection of a top or apex end ring to a segment.
FIG. 11 is a perspective side view showing the joining of sections of the base end reinforcing ring.
FIG. 12 is a perspective view showing assembly of a part of the apex reinforcing ring.
FIG. 13 is a sectional plan view showing several of these segments joined together and a system for temporarily clamping the segments to glue adjacent segments together.
FIG. 14 is a sectional plan view showing an alternative system for adjoining segments of the dome structure together.
FIG. 15 is a perspective view of a dome showing a further alternative for joining segments together.
FIG. 16 is an elevation view, partially broken away, showing a feature of the joining system of FIG. 15.
DESCRIPTION OF PREFERRED EMBODIMENTS
In the drawings, FIG. 1 shows a dome structure 10 constructed according to the principles of the invention. The dome 10 includes a large number of segments 11 joined together at joints 12 lying in planes perpendicular to a plane of base ends 13 of the segments. The joint planes all intersect a center axis of the dome. Preferably a circular reinforcing ring 14 is secured to the base ends 13 of the segments. The ring 14 acts as a shape reinforcing means at the base of the structure.
As shown in FIG. 2, an apex end 16 of the dome may have an opening 17 which may have a reinforcing ring 18 secured to apex ends 19 of the segments. In FIG. 2 the dome structure 10 is shown as a true hemisphere (or half of a true hemisphere), as is preferred, but the curvature of the segments 11 may be non-circular as discussed above.
FIG. 3 illustrates that the segments 11, which preferably are pre-formed into their final curved configuration, may comprise glued laminations of a number of layers 21, laminated in the desired curved configuration. An outer layer 21a (or the outer two or three layers) may be formed of weather-resistant wood such as redwood or cedar, with inner layers 21b of other varieties of wood, not necessarily moisture-resistant.
FIG. 3 also shows one manner of joining adjacent segments 11 according to the invention. Each edge 22 of a segment may be formed with a groove 23 (see also FIG. 4), and a continuous spline 24 may be fitted into the groove 23 and glued to join the edges. Other variations may also employed, such as butting, lapping or tongue-in-groove, but it is important that the edges 22 be substantially complimentarily shaped to one another, accommodating the angle that must exist between segments. An example of this angle is a total of 4° change in segment angle at each joint, for a dome with 90 segments. To produce this joint angle, each segment edge may be 2° off perpendicular (to the surface of the segment) at the base end of the segment. The formed angularity of the edge will include any groove 23 or lap jointing structure.
However, the edge angle must vary continuously along the segment, reaching substantial perpendicularity at the apex ends 19 of the segments, as discussed above. If an opening 17 (FIGS. 2 and 5) forms the upper terminus or apex end 19 of each segment, then the edges will be very slightly off perpendicular at the apex end 19, and the end 19 will be truncated as shown in FIG. 6.
FIG. 3, a sectional plan view taken just above the base ring 14, shows the base ring receiving the bottom end of the segment in a groove of the base ring. The bottom ends 11a of the segments may be narrower in thickness, as shown in FIG. 4, than the remainder of the section, so that inner and outer ledges 11b extend over part of the base ring 14, covering the joint between the ring's groove and the segment.
FIG. 7 shows a method according to the invention for forming the continuously varying angularity of the edges 22 of the dome segments. The figure schematically illustrates the advancement of a segment 11 through a work station by powered rollers 25 which frictionally engage the segment 11. The segment may slide on a curved, complementarily shaped support block 26 as indicated. As the segment advances, a router blade 27 on a shaft 28 revolves and removes material to shape the edge 22. The rotating shaft 28, however, changes its angular orientation as the segment advances in proper timing or phase with the advancing position of the segment.
In the example system illustrated, a motor M1 on a movable platform 29 drives the router shaft 28 and router blade 27. The platform 29 is mounted for pivotal movement about a pivot axis 31 generally parallel to the segment 11 at the area being routed, and generally through the router blade 27. A motor M2 fixed in position moves the platform about the pivot axes in timing with the progress of the segment-advancing rollers 25. The rollers 25 may be driven by the same motor M2 (by driving connections not shown), so that a fixed mechanical linkage exists between the movement of the rollers 25 and tilting of the router blade 27, or there may be a separate motor (not shown) for the rollers. In the latter case, the motors can be constant-speed motors which are geared to provide the proper speeds at the two locations and which are started and stopped at the proper time.
The segment 11 preferably has been rough cut to dimensions slightly wider than final dimensions, then a template 30 for the segment is attached to one side as illustrated. The router's following collar 27a engages the edge of the template to guide the router to remove the desired amount of material.
In the example given above, with a two degree maximum deviation from horizontal at the base end of each segment edge, the router blade 27 will need to be changed in its orientation from near 0° tilt at the apex end 19 to 2° at the base end 13.
When one edge 22 of a segment 11 has been shaped by a pass through the system shown in FIG. 7, the segment may be turned around to feed the segment through in the opposite direction, base end 13 first. With the segments still concavely upward, this requires the tilting of the router to be opposite that used in forming the first edge--from 2° tilt to 0° tilt as the segment is fed through from end to end.
The router blade 27 can form any desired shape, depending on the joint configuration used. It may form an edge with a central continuous groove, or a lap joint, or a tongue or groove of a tongue-in-groove joint (see FIG. 12), with another router blade for the complimentary edge. Flat butt glue joints may be used if desired, although some form of interlocking or overlapping glue joint is preferable. The tongue-in-groove or splined joints are self-centering and therefore preferred.
The edges 22 of the segments 11 can be formed by another procedure in accordance with the invention, without the use of varying-angle router apparatus 27, 28, 29 illustrated in FIG. 7. After rough-cutting the segment larger than finished width dimensions (several can be cut out of a rectangular arcuately formed laminate with a table saw), the segment can be edge-trimmed with the template 30 attached by use of a fixed-axis router, generally as shown in FIG. 7 but without router tilt. This trimming operation will leave the segment width still slightly oversized. Then, the arcuate segment can be laid on one edge on a surface joiner table which is planar. Since the desired finished edge lies in a plane (each joint lies in a vertical axes plane as discussed above), the joiner can be used to form the edge into substantially a perfect plane. After one edge 22 is formed, the other can be formed similarly, with care to take the segment down to finished width and not further.
Thus, the template 30 plays an important part in forming the finished segment--by establishing the correct edge curvature, it establishes the plane in which the final edge should lie, found by laying the segment on an edge on a planar surface.
It should be noted that the segments, if developed or opened to a flat configuration, would not form trapezoid shapes. The long edges bulge outwardly, similar to lines of longitude on a hemisphere of a globe.
FIG. 8 indicates an assembly layup arrangement whereby the base ends 13 of the segments are held in position by a base circular jig 33 while the segments are fitted together, and by an apex circular jig 34 at the apex ends 19 of the segments. The jigs 33 and 34 may actually comprise the reinforcing rings 14 and 18, respectively (or progressive sections as these rings are assembled), if these are to be included in the assembled dome. A central post 36 temporarily holds the top ring 34 in position with respect to the bottom ring 33 during assembly. This jig arrangement assures that the segments are assembled accurately in the desired dome configuration, without error buildup as assembly progresses. FIG. 5 shows the top or apex reinforcing ring 18 in plan view.
FIGS. 9 and 10 show examples of preferred constructions for the bottom and top reinforcing rings 14 and 18. The base ring 14 may be formed of a series of laminated layers 36, with a channel or groove 37 for receiving the narrowed end 11a at the base end of the segment 11. The apex ring 18 may be formed of three components--an outer piece 46, an inner piece 47 and a spacer piece 48 as shown. All three preferably are comprised of wood laminations, with laminated layers oriented differently in the spacer 48 than in the inner and outer pieces 46 and 47. The composite rings 14 and 18 may be secured to the segment ends 13 and 19 by any of several means, such as glue, mechanical fasteners or both. The rings may be formed in arcuate segments, such as four per ring.
FIG. 11 shows a preferred arrangement for connecting two adjacent ring segments of the base ring 14 together. Preferably a bolt or other fastener 49 is used in conjunction with gluing to secure the sections together. The bolt 49 has a woodscrew end 49a screwed into one section 14a of the base ring as illustrated. The other section 14b is pre-drilled to receive a machine bolt end 49b of the bolt 49 when the sections are put together. At a lateral opening 50 (which is later plugged) a wood spacer 52, washer 53 and nut 54 are assembled onto the machine bolt end, and the nut can be tightened by a striking tool from the opening 50. Portions of the base sections 14a and 14b (such as on either side of the groove 37) can be staggered at the joint if desired.
FIG. 12 shows a similar joint for two adjacent sections of the top ring, but involving only the middle or spacer piece 48. The middle piece 48 is assembled of sections progressively as the dome is assembled of segments, with the apex ends of segments fitting into a groove 56 of the middle piece 48. The outer and inner pieces 46 and 47 (see FIG. 10) are added and secured by gluing and bolting or screwing to the middle spacer piece 48. They are secured so as to stagger the joints of the middle piece 48, adding strength and covering bolt access holes such as at 57. The apex ring 18 may be built of four or more arcuate sections of each component.
FIG. 13 shows one method for holding adjacent segments tightly together at their edges during gluing of a joint 60. Jigs 61 and 62 are temporarily held to the segments as shown. The jig 61 is held by wood screws 63, which need not penetrate very deeply into the segments and form only a small hole which will virtually disappear later; the jigs 62 is held by a clamp 64 to a segment 11a being attached. The jigs are then clamped toward each other by a clamp 66. This may be done at two or three locations spaced vertically along the joint 60 to produce a glue joint of good integrity.
FIG. 14 shows an alternative type of joint 70 which may be employed to hold adjacent segments 11 together, particularly for situations where the dome is used in wet or severe weather conditions where glue joints would be subject to attack and possible deterioration. Dovetail grooves may be formed in each segment edge, and a long dovetail insert 71 may be pushed or driven through the length of the grooves, from base end to apex end. The dovetail insert may be of aluminum, copper or plastic rather than wood, for weather resistance.
FIGS. 15 and 16 show another system for drawing and holding the segments together. A dome 75, shown here as not having an apex opening (although it can have) may be held together by a series of tension bolts or cables 76, for example three cables spaced at different levels as illustrated. The cables pass through holes in each segment, with the last several segments holes on one side of a joint 77 inclining slightly upwardly or downwardly so the ends 78 of the cable/bolt can overlap as in
FIG. 16. The segment 11j in which the joint occurs can have a steel reinforcement plate 72 inlaid, for bearing against by nuts 81 which draw the multiplicity of segments together into a tight circle. Nut tightening can be through access holes 82 in one face or the other of the dome. A turnbuckle could be used in lieu of the nut and steel reinforcing plate 77, still hidden from view in the segment(s). This system gives the dome high strength and integrity particularly in weather extremes, and can avoid any need for splined or tongue-in-groove edge connections, making assembly quite simple. Aesthetically, the dome 75 appears similar to the dome 10, since all hardware is hidden.
It should be understood that terms such as "dome" as used in this description are intended in a general sense, and not to limit the invention to a truly circular hemispherical dome. Also, terms such as "upper" and "lower," etc. are used only in reference to the drawings; the dome structure of the invention can be positioned in any orientation. Further, although equally-sized segments are shown, the widths of the segments can vary somewhat if desired. Also, an entry doorway can interrupt the dome structure if needed.
The above described preferred embodiments are intended to illustrate the principles of the invention, but not to limit its scope. Other embodiments and variations to this preferred embodiment will be apparent to those skilled in the art and may be made without departing from the scope of the invention as defined in the following claims. | A dome structure is formed of a large number of identical arcuate segments secured together at the edges, with no additional visible structural members between base ends and apex ends of the segments. A reinforcing ring may be secured to the dome structure at the base ends of the segments, and another may be secured at the apex ends, if the apex or top end of the dome has an opening. In preferred embodiments the arcuate segments are formed of laminated wood, with a spline or other type of overlapped glued connection between adjacent segments. At the edges of the segments, angularity varies from virtually perpendicular at the apex end to a maximum deviation from perpendicular at the base ends, and this is addressed by a special method of shaping the segment edges. | 4 |
BACKGROUND
Many sites housing network equipment are remote and unstaffed. As a result, no human is typically present to diagnose equipment failures on-site. Dispatching a technician to do so can be costly and time-consuming. It may be advantageous to be able to diagnose such failures remotely.
SUMMARY OF THE INVENTION
A method for initiating a telephone call to a telephone line that is connected to a modem and an answering machine, the modem being configured to connect to the telephone call prior to the answering machine, determining whether the modem has connected to the telephone call, determining, if the modem has not connected to the telephone call, whether the answering machine has connected to the telephone call and providing a first indication to a user if neither of the modem nor the answering machine has connected to the telephone call.
A system having a networking component connected to a power source, a modem connected to the networking component, to the power source, and to a telephone line, the modem being configured to answer an incoming call on the telephone line after a first predetermined time period and a telephone answering machine connected to the power source and to the telephone line, the answering machine being configured to answer the incoming call on the telephone line after a second predetermined time period, the second time period being longer than the first predetermined time period.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an exemplary system according to the present invention.
FIG. 2 shows an exemplary method according to the present invention.
DETAILED DESCRIPTION
The exemplary embodiments of the present invention may be further understood with reference to the following description and the appended drawings, wherein like elements are referred to with the same reference numerals. The exemplary embodiments of the present invention describe systems and methods for diagnosing problems with network hardware.
The exemplary embodiments of the present invention include systems and methods whereby network problems may be diagnosed remotely with more precision than previously possible. This may prevent excessive site trips by technicians; such trips may be time-consuming and expensive, and may also be inadequate to resolve certain types of problems (e.g., power outages). Moreover, the exemplary embodiments of the present invention may be implemented with only minor cost and difficulty.
FIG. 1 illustrates an exemplary system 100 according to the present invention. The system may be administered by a management console 110 , which may be, for example, a user workstation dedicated to operating the system 100 , a user workstation dedicated to network management but performing additional tasks besides those disclosed in this disclosure, a general-purpose workstation capable of performing these tasks, etc. The management console 110 may be a dedicated hardware component or may be a software application running on a computer system that also performs other tasks.
The management console 110 may communicate with other elements of the system 100 via a public switched telephone network (“PSTN”) 120 . The PSTN 120 is a network of circuit-switched telephone networks, and may typically use E.163/E.164 addresses (i.e., telephone numbers) for addressing of data. The PSTN may include a plurality of telephone lines, including telephone line 130 , to which the modem 140 and the answering machine 150 are both connected.
Using the PSTN 120 , the management console 110 may have access to the modem 140 and the answering machine 150 . The modem 140 may be any type of modem that may be capable of communicating with a computer and of conducting data communications over the PSTN 120 . The answering machine 150 may be a device that monitors traffic over a single phone line of the PSTN 120 (e.g., the phone line 130 ) and that is configured to answer an incoming call after a preselected period of time. The answering machine 150 may be configured to then play an outgoing message and record an incoming message. In the exemplary system 100 of the present invention, both the modem 140 and the answering machine 150 are configured to answer an incoming call after a respective preselected period of time; the configured period of time for the answering machine 150 may be longer than that for the modem 140 . In one exemplary embodiment, the modem 140 may be configured to answer an incoming call on the phone line 130 after one ring, while the answering machine 150 may be configured to answer an incoming call on the phone line 130 after three rings.
The modem 140 may be connected to a network component 160 . The network component 160 may be, for example, a data router, but may also be any other type network component which is desirable to monitor remotely, and which may either incorporate a modem internally or may be attached to one. Those of skill in the art will understand that while FIG. 1 illustrates a system 100 including a network component 160 connected to a separate modem 140 , the principles of the present invention may be equally applicable to a network component 160 that includes an integral modem.
The modem 140 , answering machine 150 , and network component 160 may be connected to the same power source 170 . FIG. 1 illustrates that the power source 170 is a power strip or surge protector; however, the power source 170 may be any comparable component suitable for causing the modem 140 , the answering machine 150 , and the network component 160 to respond identically to power failures.
FIG. 2 illustrates an exemplary method 200 by which the exemplary system 100 of FIG. 1 may operate. Those of skill in the art will understand that while the method 200 is described herein with specific reference to the system 100 , it is equally applicable to any other combination of elements that may be capable of executing the steps described. In step 210 , a user of the management console 110 initiates a process to diagnose a problem involving the network component 160 . This may occur because the user has become aware of the existence of an undiagnosed problem with the network component 160 (e.g., because a signal has been lost on a data link to the network component 160 , because a loss of functionality of the network component 160 has been reported by someone attempting to access the network component 160 , etc.) or as part of periodic maintenance to communicate with the network component 160 (which may be one of a plurality of similar components comprising a network) to determine whether any problems have occurred. Alternately, in other embodiments of the present invention, the process may be initiated automatically (e.g., by a computer program running on the management console 110 in embodiments where the management console 110 is a hardware component; by the management console 110 itself in embodiments where the management console 110 is a computer program, etc.) either in response to a specific problem involving the network component 160 or periodically to monitor the performance of the network component 160 as well as of other network components (not shown).
In step 220 , the management console 110 dials the phone line 130 via the PSTN 120 . Dialing may be accomplished, for example, via a modem (not shown) that is connected to or part of the management console 110 , or via another mechanism through which data communications may be conducted. In step 230 , the modem 140 does or does not answer the incoming call on the phone line 130 within a first predetermined time period (e.g., one ring, five seconds, etc.). If the modem 140 answers, then in step 240 , data communication may take place between the management console 110 and the modem 140 . This communication may involve the diagnosis of a problem involving the network component 160 , to which the modem 140 is connected, or it may simply confirm whether the network component 160 is operating and/or whether the network component 160 is operating properly. Following step 240 , the method terminates.
If, however, the modem 140 does not receive the incoming call in step 230 , the method proceeds to step 250 . In step 250 , the answering machine 150 does or does not answer the incoming call on the phone line 130 within a second predetermined time period (e.g., three rings, ten seconds, etc.). If the answering machine 150 answers the incoming call, then the method continues at step 260 .
In step 260 , the answering machine 150 plays an outgoing message over phone line 130 and PSTN 120 . The contents of the message are unimportant; the fact that the message is transmitted indicates to the management console 110 (or a user thereof) that there is a problem with either the modem 140 or the network component 160 . Following step 260 , the method terminates. Those of skill in the art will understand that the next step in diagnosing and repairing a problem with the modem 140 or the network component 160 may be to dispatch a technician to the site where the network component 160 is located; however, this or other subsequent troubleshooting steps are beyond the scope of the exemplary method 200 .
While it is not required, the outgoing message played by the answering machine 150 may have specific characteristics. For example, the outgoing message may be encoded to identify the hardware, encrypted to prevent attackers from using it to do network mapping, etc. In another exemplary embodiment, the answering machine 150 may have the ability to measure and announce the temperature at the site in the outgoing message.
However, if the answering machine 150 does not answer in step 250 , then the method proceeds to step 270 . In this step, the problem may be diagnosed as a problem involving the power source 170 . This presumption may be made because simultaneous failure of the network component 160 , modem 140 and the answering machine 150 is a rare occurrence; if the answering machine 150 does not answer, it is reasonable to presume that power must have failed. Following step 270 , the method terminates. As discussed above, further troubleshooting steps may follow but are beyond the scope of the exemplary method 200 . For example, after concluding that there is a problem with the power source 170 , a user of the management console 110 may dispatch a technician to the site where the power source 170 is located to determine the nature of the problem (e.g., in embodiments where the power source 170 is a power strip, surge protector, etc.), or may alternately contact the power provider for the site to inform them of the problem.
As described above, performance of the above exemplary method may be automated to periodically poll various network components for information about their status. In another exemplary embodiment including such automation, results of such polling may be recorded in a log file. Such a log file may then be analyzed to determine whether any discovered problems may be occurring systematically, rather than in isolated instances.
In another exemplary embodiment of the present invention, the system may include an answering machine that may be connected to the same power source as the network component, but may also provide a battery backup. In such an embodiment, the answering machine may be programmed to automatically place an outgoing call (e.g., to a management console) when it detects a power failure. This may thus automate the process of calling the modem for continuous monitoring.
The exemplary embodiments of the present invention may thus make it possible to more effectively remotely diagnose problems affecting network hardware components. Using the above-described exemplary embodiments, the information obtained by simply placing a phone call may inform a technician as to the specific nature of such problems, often saving a site trip that may be time-consuming and expensive. Further, the implementation of the above exemplary embodiments may be very simple, merely requiring commonly-accessible resources such as a phone line, a modem, an answering machine and a power strip.
The present invention has been described with reference to the above specific exemplary embodiments. However, those of ordinary skill in the art will recognize that the same principles may be applied to other embodiments of the present invention, and that the exemplary embodiments should therefore be read in an illustrative, rather than limiting, sense. | A system and method for initiating a telephone call to a telephone line that is connected to a modem and an answering machine, the modem being configured to connect to the telephone call prior to the answering machine, determining whether the modem has connected to the telephone call, determining, if the modem has not connected to the telephone call, whether the answering machine has connected to the telephone call and providing a first indication to a user if neither of the modem nor the answering machine has connected to the telephone call. | 7 |
BACKGROUND
[0001] Panels used as ceiling tiles or walls fall into the category of building products and provide architectural value, acoustical absorbency, acoustical attenuation and utility functions to building interiors. Commonly, panels, such as acoustical panels, are used in areas that require noise control. Examples of these areas are office buildings, department stores, hospitals, hotels, auditoriums, airports, restaurants, libraries, classrooms, theaters, cinemas, as well as residential buildings.
[0002] To provide architectural value and utility functions, an acoustical panel, such as a ceiling panel for example, is substantially flat and self-supporting for suspension in a typical ceiling grid system or similar structure. Thus, acoustical panels possess a certain level of hardness and rigidity, which is often measured by its modulus of rupture (“MOR”). To obtain desired acoustical characteristics, an acoustical panel also possesses sound absorption as well as sound transmission reduction properties.
[0003] Currently, most acoustical panels or tiles are made using a water felting process preferred in the art due to its speed and efficiency. In a water-felting process, the base mat is formed utilizing a method similar to papermaking. One version of this process is described in U.S. Pat. No. 5,911,818 issued to Baig, herein incorporated by reference. Initially, an aqueous slurry including a dilute aqueous dispersion of mineral wool, lightweight aggregate, fibers, binders and other additives is delivered onto a moving foraminous wire of a Fourdrinier-type mat forming machine. Water is drained by gravity from the slurry and then optionally further dewatered by means of vacuum suction and/or by pressing. Next, the dewatered base mat, which may still hold some water, is dried in a heated oven or kiln to remove the residual moisture. Panels of acceptable size, appearance and acoustic properties are obtained by finishing the dried base mat. Finishing includes surface grinding, cutting, perforation/fissuring, roll/spray coating, edge cutting and/or laminating a scrim or veil onto the panel.
[0004] A typical acoustical panel base mat composition includes inorganic fibers, cellulosic fibers, binders, and fillers. As is known in the industry, inorganic fibers can be either mineral wool (which is interchangeable with slag wool, rock wool and stone wool) or fiberglass. Mineral wool is formed by first melting slag and minor additives at 1300° C. (2372° F.) to 1650° C. (3002° F.). The molten mineral is then spun into wool in a fiberizing spinner via a continuous air stream. Inorganic fibers are stiff, giving the base mat bulk and porosity.
[0005] Cellulosic fibers act as structural elements, providing both wet and dry basemat strength. The strength is due to the formation of countless hydrogen bonds with various ingredients in the base mat, which is a result of the hydrophilic nature of the cellulosic fibers.
[0006] A typical base mat binder used is starch. Typical starches used in acoustical panels are unmodified, uncooked corn or wheat starch granules that are dispersed in the aqueous slurry and distributed generally uniformly in the base mat. Once heated in the presence of moisture during the drying process, the starch granules become cooked and dissolve, providing binding ability to the panel ingredients. Starches not only assist in the flexural strength of the acoustical panels, but also for hardness and rigidity of the panel. In certain panel compositions having a high concentration of inorganic fibers, a latex binder is used as the primary or as a secondary binding agent.
[0007] Typical base mat fillers include lightweight inorganic materials. A primary function of lightweight fillers is to provide bulking within the mat, thus providing a lower density and lighter weight ceiling panel. An example of a lightweight filler includes expanded perlite. Even though the term “filler” is used throughout this disclosure, it is to be understood that each filler has unique properties and/or characteristics that can influence the rigidity, hardness, sag, sound absorption, and reduction in the sound transmission in panels. Heavyweight fillers can also be added, and include calcium carbonate, clay, or gypsum, for example.
[0008] Wet felted ceiling products typically utilize starch and recycled newsprint as the principal binders, both of which are hygroscopic. In the presence of humidity, these binders absorb water and lose physical integrity, leading to sag. Some existing products use a formaldehyde resin backcoating. Although this is a very effective and low cost solution, there has been a move to reduce or eliminate the use of formaldehyde in building products for environmental reasons.
[0009] Thermoset polymer resins, such as polycarboxylate resins, have been used successfully. See e.g., U.S. Pat. No. 8,536,259. However, these resins are too expensive to be commercially viable.
[0010] U.S. Pat. No. 4,444,594 describes the use of acid cured compositions which are produced by reacting magnesium oxide and an acid phosphate, chloride, or sulfate salt in the presence of inorganic filler, an amino alcohol acid attack control agent, and water to form a curable slurry. The amino alcohol acid attack control agent is said to be required to prevent the degradation of mineral wool used in ceiling boards. However, the required use of the amino alcohol acid attack agent increases the cost of the coating and contributes unnecessary VOC's to the coating. When present as an amino compound, the inclusion of this weak base slows the reaction rate. Furthermore, the compositions contain between 50.5% and 57.9% solids.
[0011] Therefore, there is a need for a sag resistant acoustical panel which is low cost and which does not contain formaldehyde or amino alcohols.
SUMMARY OF THE INVENTION
[0012] One aspect of the invention is a method for making a building panel. In one embodiment, the method includes combining water, an inorganic fiber, and one or more binders to form a slurry, wherein at least one of the binders comprises starch; shaping the slurry into a panel; applying a coating to a back side of the panel, the coating comprising a reaction product of magnesium oxide and a phosphate salt in the absence of an amino alcohol; and drying the panel.
[0013] Another aspect of the invention involves a building panel. In one embodiment, the building panel includes a base mat comprising an inorganic fiber, and one or more binders, wherein at least one of the binders comprises starch; and a coating on a back side of the base mat, the coating being the reaction product of magnesium oxide and a phosphate salt.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a graph showing the temperature rise of different sources of MgO as a function of time.
[0015] FIG. 2 is a graph showing the temperature rise as a function of time for coatings having different solids content.
[0016] FIG. 3 is a graph showing the temperature rise as a function of time for coatings containing a hectorite clay thickener.
[0017] FIG. 4 is a graph showing the temperature rise as a function of time for coatings incorporating a fly ash filler at varying usage levels.
[0018] FIG. 5 is a graph showing the temperature rise as a function of time for coatings with a fly ash filler and phosphoric acid.
[0019] FIG. 6 is a graph showing the temperature rise of coatings using varying levels of phosphoric acid and differing water/solids ratios as a function of time.
DETAILED DESCRIPTION OF THE INVENTION
[0020] The invention meets the need for a cost-effective, non-formaldehyde containing sag resistant coating for use with ceiling tile. The coating is inorganic, fast reacting, and low cost, and it provides a high level of sag resistance. The coating is the reaction product of magnesium oxide and a phosphate. One advantage of the magnesium oxide/phosphate coating is the controllable high rate of reaction, which allows for faster processing speed for producing the ceiling tile.
[0021] The ceiling tile product process is a high speed operation, with finishing line speeds of over 150 ft/min. In order for a coating to be compatible with these line speeds, it has to cure in under 20 to 30 sec. In addition, after application, it needs to maintain its integrity during subsequent operations including a relatively high temperature drying operation in which the back of the surface of the panel reaches a temperature of about 204° C. (400° F.).
[0022] The magnesium oxide/phosphate coating can be made to react in under 30 sec and it forms an inorganic glass which is stable to high temperature.
[0023] The main components of the inorganic coating are a high reactivity magnesium oxide and a phosphate salt and optional filler. The magnesium oxide is commercially available is different grades of reactivity. Reactivity is typically based on surface area, which is the result of the burning temperature at which the magnesium oxide is produced. The higher the surface area, the higher is the reactivity. Suitable high reactivity magnesium oxide includes, but is not limited to, MagChem 10CR, MagChem 30, MagChem 35, MagChem 40, and MagChem 50 (available from Martin Marietta) and Baymag 30 and Baymag 40 (available from Baymag Inc.) and equivalents. More reactive grades of MgO can be used to provide a faster reaction rate to accommodate faster finishing line speeds, if desired. The gauge of reactivity for MgO is generally given by the measured surface area in m 2 /g. Lab work was conducted using a very low reactivity grade of MgO such as the MagChem 10CR product (est. <20 m 2 /g surface area) in order to provide handling time. In production, it would be expected that a more reactive grade of MgO would be required to provide the required quick set time of less than 30 seconds such as the MagChem 30 product (20-30 m 2 /g), MagChem 30 product (30 m 2 /g) or an even more reactive grade of MgO.
[0024] The phosphate salt is the second component. The phosphate salt should be slightly soluble in water which aids the reaction and should be slightly acidic. Suitable phosphate salts include, but are not limited to, potassium phosphate salt (KH 2 PO 4 ), and sodium phosphate (NaH 2 PO 4 ). However, the sodium phosphate products yielded a softer reaction product that was less suitable for this application than those made with potassium phosphate. Phosphate salts which are insoluble in water (e.g., Ca 3 (PO 4 ) 2 and Li 3 PO 4 ), tend to react too slowly, while those that are too soluble (e.g., LiH 2 PO 4 and K 2 HPO 4 ) tend to form dispersed precipitates.
[0025] Phosphates that are not slightly acidic, such K 3 PO 4 , react too slowly. Highly acidic phosphates, such as phosphoric acid, can provide a very rapid reaction rate resulting in a highly dispersed reaction product that is unsuitable for this application. Phosphoric acid can, however, can be added at a judicious level as an accelerator to provide a faster reaction rate. The amount of added phosphoric acid is dictated by such factors as the desired reaction rate, the presence of filler or thickeners which by themselves might act to slow the reaction rate, the water/solids ratio, the temperature of the mix, etc.
[0026] Ammonium phosphates such as (NH 4 )H 2 PO 4 and (NH 4 ) 2 HPO 4 can also be used as reactants although they are less preferable since they evolve ammonia gas as a reaction product, which is undesirable in a production environment.
[0027] A filler or a functional additive is an optional third component of the coating. The filler ideally should be slightly soluble in water thus permitting it to react with the phosphate salt and become an integral part of the reaction product. Fillers that meet this requirement include Type C fly ash. Other non-reactive fillers, such as sand, can also be used but do not generally participate in the reaction. Basic fillers such as calcium carbonate are to be avoided. Functional additives include thickeners, such as smectite clay, flow aids, retarders, and the like.
[0028] Additional acid, such as phosphoric acid, can be added to accelerate the reaction rate by providing a more acidic environment to the reaction. The use of the acid can also be used to offset a less acidic phosphate salt such as K 2 HPO 4 or K 3 PO 4 .
[0029] The molar ratio of the magnesium oxide to the phosphate salt in the coating can vary from about 0.1 to about 0.9, or about 0.1 to about 0.8, or about 0.1 to about 0.7, or about 0.1 to about 0.6, or about 0.1 to about 0.5, or about 0.1 to about 0.4, or about 0.1 to about 0.3. A molar ratio of about 0.3 provides good results.
[0030] The reaction of the magnesium oxide and the phosphate salt can be accelerated by the addition of an acid, such as phosphoric acid.
[0031] It was surprisingly found that the magnesium oxide/phosphate coating does not degrade the mineral wool in the ceiling panel. Thus, the use of the amino alcohol taught in U.S. Pat. No. 4,444,594 is not required, making the coating less expensive with no or minimal VOC's and easier to make.
[0032] The magnesium oxide and phosphate salt can be prepared as separate dispersions and then combined and applied uniformly across the back surface of the panel, for example by spraying. Alternatively, they can be applied over only portions of the back, for example in stripes, to achieve a reinforcing backbone along the center of a panel.
[0033] The amount of water used in preparing these coatings is desirably minimized. It has been found that more water in the coating leads to a slower reaction time, which is undesirable in a production setting where a very fast reaction time (under 30 seconds) is required. Typically, a total water/solids ratio of under about 0.5, or under about 0.45, or under about 0.4 is desired. Desirably, the coating has at least about 50% solids, or at least about 55% solids, or at least about 60% solids.
[0034] The coating will typically be applied at a solids usage of under 25 grams of solids per square foot. Usage rates of under 20 grams of solids per square foot have been shown to provide good results.
[0035] When the coating is applied to the surface of the panel, there is some penetration into the panel, e.g., up to about 5% of the thickness of the panel. The coating has good adhesion to the panel.
[0036] Fibers are present in the acoustical panel as inorganic fibers, organic fibers or combinations thereof. Inorganic fibers can be mineral wool, slag wool, rock wool, stone wool, fiberglass or mixtures thereof. The inorganic fibers are stiff, giving the base mat bulk and porosity. Inorganic fibers are present in the acoustical panel in amounts of about 0% to about 95% based on the weight of the panel. In some embodiments, where less expanded perlite and/or cellulosic fiber is present, the inorganic fibers are present in an amount of about 25% to about 95%, or about 50% to about 95%, or about 55% to about 95%, or about 60% to about 95%, or about 65% to about 95%, or about 70% to about 95%, or about 75% to about 95% or about 80% to 95%. In other embodiments, where more expanded perlite and/or cellulosic fibers are present, the amount of inorganic fibers can be in the range of about 5% to about 90%, or about 5% to about 80%, or about 5% to about 70%, or about 5% to about 60%, or about 5% to about 50%, or about 5% to about 40%, or about 5% to about 30%, or about 5% to about 25%, or about 5% to about 20%. At least one embodiment of the acoustical panel uses mineral wool as the preferred fiber.
[0037] Cellulosic fibers, an example of a renewable organic fiber, act as structural elements providing both wet and dry base mat strength. The strength is due to the formation of hydrogen bonds with various ingredients in the base mat, which is a result of the hydrophilic nature of the cellulosic fibers. Cellulosic fibers in the base mat range from about 0% to about 25% by weight of the panel, preferably about 10% to about 20% by weight of the panel and most preferably from about 12% to about 20% by weight of the panel. One preferred cellulosic fiber is derived from recycled newsprint.
[0038] Starch is optionally included in the base mat as a binder. Typical starches are unmodified, uncooked starch granules that are dispersed in an aqueous slurry and become distributed generally uniformly through the base mat. The base mat is heated in the presence of moisture, cooking and dissolving the starch granules to bind the panel ingredients together. Starch not only assists in the flexural strength of the acoustical panels, but also improves the hardness and rigidity of the panel. In addition, the base mat optionally includes starches in the range of about 1% to about 15% by weight of the panel, more preferably from about 5% to about 10% and most preferably from about 7% to about 10% by weight of the panel.
[0039] Typical optional base mat fillers include both lightweight and heavyweight inorganic materials. Examples of heavyweight fillers include calcium carbonate, clay or gypsum. Other fillers are also contemplated for use in the acoustical panels. The ball clay can also be used in the range of about 0% to about 4% by weight of the panel.
[0040] An example of a lightweight filler is expanded perlite. Expanded perlite is bulky, reducing the amount of filler used in the base mat. Primary functions of the filler are reduced density, improved flexural strength and hardness of the panel. Even though the term “filler” is used throughout this discussion, it is to be understood that each filler has unique properties and/or characteristics that can influence the rigidity, hardness, sag, sound absorption and reduction in the sound transmission in panels. The expanded perlite in the base mat of this embodiment is present in amounts ranging from about 5% to about 80% by weight of the panel, or about 10% to about 80%, or about 20% to about 80%, or about 20% to about 70%, or about 30% to about 70%, or about 40% to about 70%, or about 40% to about 60%, or about 45% to about 60%.
[0041] Another optional ingredient used in fire rated acoustical panels is clay, which is typically included to improve fire resistance. When exposed to fire, the clay does not burn; instead, it sinters. Fire rated acoustical panels optionally include from about 10% to about 30% clay by weight of the panel, with a preferred range of about 10% to about 20% clay by weight of the panel. Many types of clay are used including but not limited to Spinks Clay and Ball Clay from Gleason, Tenn. and Old Hickory Clay from Hickory, Ky.
[0042] A flocculant is also typically added to the furnish used in producing acoustical panels. The flocculant is preferably added as a very dilute solution and is used in the range of about 0.05% to about 0.15% by weight of the panel and more preferably from about 0.05% to about 0.10% by weight of the panel. Useful flocculants include polyacrylamides.
[0043] In one embodiment of making base mats for the acoustical panels, an aqueous slurry is preferably created by mixing water with the mineral wool, expanded perlite, cellulosic fibers, starch, and ball clay. Mixing operations are preferably carried out in a stock chest, either in batch modes or in continuous modes. The amount of added water is such that the resultant total solid content or consistency is in the range of about 1% to about 8% consistency, preferably from about 2% to about 6% and more preferably from about 3% to about 5%.
[0044] Once a homogeneous slurry including the above-mentioned ingredients is formed, the flocculant is added in-line and the slurry is transported to a headbox, which provides a steady flow of the slurry material. The slurry flowing out of the headbox is distributed onto a moving foraminous wire to form the wet base mat. Water is first drained from the wire by gravity. It is contemplated that in certain embodiments, a low vacuum pressure may be used in combination with, or after draining water from the slurry by gravity. Additional water is then optionally removed by pressing and/or using vacuum-assisted water removal, as would be appreciated by those having ordinary skill in the art.
[0045] Once formed, the formed base mats preferably have a bulk density between about 7 lbs/ft 3 (112 kg/m 3 ) and about 30 lbs/ft 3 (480 kg/m 3 ), more preferably between about 8 lbs/ft 3 (128 kg/m 3 ) to about 25 lbs/ft 3 (400 kg/m 3 ) and most preferably from about 10 lbs/ft 3 (144 kg/m 3 ) to about 20 lbs/ft 3 (320 kg/m 3 ).
[0046] The formed base mat is then cut and converted into the acoustical panel through finishing operations as are well known by those having ordinary skill in the art. Some of the preferred finishing operations include, among others, surface grinding, coating, perforating, fissuring, edge detailing and/or packaging.
[0047] A magnesium oxide/phosphate coating is applied during the finishing operation either as a combined MgO-phosphate dispersion or as individual dispersions applied in rapid succession. If applied as a combined dispersion, it would be necessary that the individual MgO and phosphate components be combined just prior to their application to the back surface of the panel.
[0048] Perforating and fissuring contribute significantly to achieving improved acoustical absorption value from the above-described base mats. Perforating operations provide multiple perforations on the surface of a base mat at a controlled depth and density (number of perforations per unit area). Perforating is carried out by pressing a plate equipped with a predetermined number of needles onto a base mat. Fissuring provides shallow indentation of unique shapes onto the surface of a formed base mat with, for example, a roll equipped with a patterned metal plate. The perforating and fissuring steps both open the base mat surface and its internal structure, thereby allowing air to move in and out of the panel. Openings in the base mat also allow sound to enter and be absorbed by the base mat core.
[0049] In addition, the acoustical panels are optionally laminated with a scrim or veil. It is also contemplated that the present acoustical panels can be manually cut with a utility knife.
[0050] Once formed, the present finished acoustical panels preferably have a bulk density between about 9 lbs/ft 3 (144 kg/m 3 ) and about 32 lbs/ft 3 (513 kg/m 3 ), more preferably between about 10 lbs/ft 3 (160 kg/m 3 ) to about 27 lbs/ft 3 (433 kg/m 3 ) and most preferably from about 10 lbs/ft 3 (176 kg/m 3 ) to about 22 lbs/ft 3 (352 kg/m 3 ). In addition, the panels preferably have a thickness between about 0.2 inches (5 mm) and 1.5 inches (38 mm), more preferably between about 0.3 inches (8 mm) to 1.0 inch (25 mm) and most preferably from about 0.5 inches (13 mm) to about 0.75 inches (19 mm).
[0051] By about, we mean within 10% of the value, or within 5%, or within 1%.
EXAMPLES
Example 1
[0052] 10.0 grams of MgO was measured into a cup. 10.0 grams of KH 2 PO 4 and 10.0 grams of water were measured into a separate cup and stirred to dissolve the phosphate. The solid MgO was added to the KH 2 PO 4 and water mixture, and mixed. The temperature rise of the mixture was measured using a thermocouple. The mixtures are shown in Table 1.
[0053] The results are shown in FIG. 1 . In Trial 1 using MagChem 10 CR, there was no apparent reaction after 2 min, although there was an apparent setting after about 60 min. There was a very rapid reaction in Trial 2 using MagChem 30, with setting in under 5 sec and a hard reaction product. Trial 3 using Baymag 30 had a very rapid reaction with steam generation and a hard reaction product. Trial 4 using Baymag 40 showed a very rapid reaction with steam generation and a hard reaction product. Trial 5 using MagChem 10 CR but at a lower water/solids ratio had a slow reaction but gradual heating occurred, and a hard reaction product formed.
[0054] The MagChem 10 product appears to be quite unreactive showing no setting at an m value of 0.3 and a water/solids (W/S) ratio of 0.5. After more than 60 min, the mixture did harden. Lowering the W/S ratio to a value of 0.25 (i.e., less water) appeared to slightly speed up the reaction. After more than 60 min, this mixture also hardened.
[0055] The MagChem 30 product appears to be highly reactive, even more reactive than the Baymag 30 and Baymag 40 products.
Example 2
[0056] The effect of the amount of water on the reaction rate was studied. KH 2 PO 4 and water were measured into a cup. MgO (BayMag 40) was measured separately and then added to the KH 2 PO 4 and water mixture, and mixed. The temperature rise of the mixture was measured using a thermocouple. The mixtures are shown in Table 2 with each mixture being run twice.
[0057] The Trial 1 formulations appeared to harden within seconds.
[0058] The solids in the Trial 2 formulations segregated to the bottom and set up. The top remained soft after 5 min.
[0059] The solids in the Trial 3 formulations segregated to the bottom leaving excess water on the surface. A thin layer of bottoms solids did set up to some degree.
[0060] The results are shown in FIG. 2 . When the sample has less than about 50% solids, the reaction is too slow for production speeds.
Example 3
[0061] The use of a thickener, hectorite clay, in the formulations was evaluated. The required amount of hectorite clay (Bentone GS available from Elementis Specialties) was mixed in water using a high speed mixer for 10 minutes in order to achieve either a 0.5% or 1.0% Bentone CS dispersion as required below. 5 grams of KH 2 PO 4 and 5.0 grams of the appropriate water/clay mixture were measured into a cup. 5 grams of MgO (Baymag 40) was measured separately and then added to the KH 2 PO 4 and water/clay mixture, and mixed. The temperature rise of the mixture was measured using a thermocouple. The mixtures are shown in Table 3.
[0062] The presence of the clay thickener accelerated the reaction as shown in FIG. 3 .
Example 4
[0063] The use of filler in the formulations was evaluated. The filler was a Type C fly ash from Hugo.
[0064] The KH 2 PO 4 and water were measured into a cup. MgO (Baymag 40) was measured separately and then added to the KH 2 PO 4 and water/clay mixture, and mixed. The temperature rise of the mixture was measured using a thermocouple. The mixtures are shown in Table 4.
[0065] The presence of up to 67% fly ash did not have a noticeable effect on the rate of reaction as shown in FIG. 4 . All of the resulting products were quite hard.
Example 5
[0066] The use of filler and acid in the formulations was evaluated.
[0067] The required amount of hectorite clay (Bentone GS available from Elementis Specialties) was mixed in water using a high speed mixer for 10 minutes in order to achieve a 2.0% Bentone CS dispersion. In trial 1 utilizing 33% filler, 10.0 grams of KH 2 PO 4 , and 6.0 grams of the water/clay mixture were measured into a cup. 10.0 grams of MgO (Baymag 40), 10.0 grams of filler (type C fly ash from Hugo), and 10.0 grams of water/clay mixture was measured separately, and the mixture was added to the KH 2 PO 4 , acid and water/clay mixture, and mixed. The temperature rise of the mixture was measured using a thermocouple. In trial 2 using 50% filler, 10.0 grams of KH 2 PO 4 , and 6.0 grams of the water/clay mixture and 0.5 ml of 85% H 3 PO 4 (only for trial 2) were measured into a cup. 10.0 grams of MgO (Baymag 40), 20.0 grams of filler (type C fly ash from Hugo), and 10.0 grams of water/clay mixture was measured separately, and the mixture was added to the KH 2 PO 4 , acid and water/clay mixture, and mixed. The temperature rise of the mixture was again measured using a thermocouple. The results are shown in Table 5.
[0068] The results of this study demonstrate that even in the presence of significant levels of filler, the addition of phosphoric acid is effective in accelerating the reaction rate to the levels necessary for production as shown in FIG. 5 .
Example 6
[0069] Perforated and patterned test strips (3 in.×23.75 in.) were prepared. Perforating refers to pressing a plate equipped with a predetermined number of needles into the base mat, while patterning provides shallow indentation of unique shapes into the surface of the basemat. The use of a perforated and patterned test strip provides a more realistic indicator of the potential sag resistance performance of a backcoating. The weight of each test panel was recorded. The edges of the test panels were taped.
[0070] KH 2 PO 4 and water were measured into a cup and stirred to eliminate lumps. MgO (Baymag 30) was measured separately and then added to the KH 2 PO 4 and water mixture and immediately poured across the top of the sag strip. Excess material was removed with a spatula. Samples 7-10 used 2% clay thickener (Bentone GS) in the water mixed with the KH 2 PO 4 . The mixtures are shown in Table 6.
[0071] The test panels were allowed to dry overnight at room temperature. The tape was then removed, and the panels were weighed and tested for sag performance by suspending the panels in a test rack such that only the short edges were supported. The test panels were then subjected to three cycles of 12 hours of 104° F./95% RH followed by 12 hours of 70° F./50% RH conditioning.
[0072] The sag performance is shown in Table 7.
[0073] Test panels 11 through 15 are un-backcoated test strips and are included as controls.
[0074] In all three series (i.e., low water/solids ratio, medium water/solids ratio, and high water/solids ratio), the sag performance appeared to improve from m=1.0 to m=0.3. Too much KH 2 PO 4 appears to be detrimental to the sag performance. Although not wishing to be bound by theory, this may be because the KH 2 PO 4 is very water soluble and not all of it is reacted in the coating.
[0075] The addition of water (i.e., a higher water/solids ratio) at a given m value appeared to affect sag performance negatively. However, the sample at a high water/solids ratio of 1.5 and with m=0.3 performed very well.
[0076] It appears that by using a low value of m (m=0.3) and a medium water/solids ratio (W/S=1.0) it is possible to achieve acceptable sag resistance at a coating solids level of 20-25 g/ft 2 .
Example 7
[0077] The use of an acid in the formulations was evaluated. MgO (MagChem 10 CR) was measured into a cup. The KH 2 PO 4 , water, and phosphoric acid were measured into a separate cup and stirred to dissolve the phosphate. The solid MgO was added to the water phosphate solution and mixed. The temperature rise of the mixture was measured using a thermocouple. The coatings were allowed to dry. The mixtures are shown in Table 8.
[0078] In Trial 1, MagChem 10 CR was used, with m=0.3, and W/S=0.50 and no acid added and where “m” refers to the molar ratio of KH 2 PO 4 to MgO and W/S refers to the water/solids ratio. There was no apparent reaction after 2 minutes and the reaction product was softer. This is possibly due to the presence of too much water. Trial 2 used MagChem 10 CR with m=0.3, W/S=0.50, and 0.1 ml 85% H 3 PO 4 added. There was a slightly more rapid and a softer reaction product. Trial 3 used MagChem 10 CR with m=0.3, W/S=0.50, and 0.5 ml 85% H 3 PO 4 added. There was a very rapid reaction with steam generation. Trial 4 used MagChem 10 CR with m=0.3, W/S=0.25, and 0.5 ml 85% H 3 PO 4 added. There was a very rapid reaction with steam generation and a hard reaction product. The results of Trials 1-4 are shown in FIG. 6 .
[0079] The phosphoric acid can accelerate the reaction with slower reacting MgO materials.
[0080] While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the invention. It being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims.
[0000]
TABLE 1
Wt.
Ratio
Trial
of
Wt. of
Wt. of
calc.
Water
#
MgO Source
MgO
KH 2 PO 4
Water
“m”*
to Solids
1
MagChem 10 CR
10.0
10.1
10.1
0.30
0.50
2
MagChem 30
10.0
10.1
10.1
0.30
0.50
3
Baymag 30
10.0
10.1
10.1
0.30
0.50
4
Baymag 40
10.0
10.1
10.1
0.30
0.50
5
MagChem 10 CR
10.0
10.1
20.1
0.30
0.25
*“m” refers to the molar ratio of KH 2 PO 4 to MgO
[0000]
TABLE 2
Wt of
Wt of
Wt. of
KH 2 PO 4 /MgO
Percent
Max Temp
Temp Rise
Trial #
KH 2 PO 4
MgO
Water
Ratio*
Solids
(° F.)
(° F.)
Slope
1
3.0
5.00
5.0
0.6
61.5%
104
33.1
0.80
2
3.0
5.00
10.0
0.6
44.4%
89
15.6
0.09
3
3.0
5.00
15.0
0.6
34.8%
97
13.8
0.05
*weight ratios
[0000]
TABLE 3
Trial
Wt. of
Wt of
Wt of
KH 2 PO 4 /MgO
#
KH 2 PO 4
Thickener
MgO
Water
Ratio*
1
3.0
None
5.00
5.0
0.60
2
3.0
0.5% Bentone GS
5.00
5.0
0.60
3
3.0
1.0% Bentone GS
5.00
5.0
0.60
*weight ratio
[0000]
TABLE 4
Wt. of
Wt. of
Wt. of
Wt. of
Trial #
KH 2 PO 4
Water
Thickener
MgO
Water
Wt. of Filler
1
10.0
6.00
2.0% Bentone GS
10.00
8.00
0.0
2
10.0
6.00
2.0% Bentone GS
10.00
10.00
10.0 (33% Type C fly ash filler)
3
10.0
6.00
2.0% Bentone GS
10.00
14.00
20.0 (50% Type C fly ash filler)
4
10.0
6.00
2.0% Bentone GS
10.00
17.00
40.0 (67% Type C fly ash filler)
[0000]
TABLE 5
Solution A
Solution B
Wt. of
Wt. of
Ml of 85%
Wt. of
Wt. of
Wt. of
Calculated
Trial #
KH 2 PO 4
Water
Thickener
H 3 PO 4
MgO
Water
Filler
pH
1
10.0
6.00
2.0% Bentone GS
0.0
10.00
10.00
20.0
3.21
2
10.0
6.00
2.0% Bentone GS
0.5
10.00
10.00
20.0
1.14
[0000]
TABLE 6
Ratio
of
Wt.
Water
Wt. of
Wt. of
of
MgO
to
calc
Percent
Trial#
KH 2 PO 4
Water
MgO
Type
Solids
“m”
Solids
1
60.8
72.5
60.0
Baymag
0.60
0.30
62.5%
30
2
87.8
76.7
40.0
Baymag
0.60
0.65
62.5%
30
3
101.3
78.8
30.0
Baymag
0.60
1.00
62.5%
30
4
50.6
105.7
50.0
Baymag
1.05
0.30
48.8%
30
5
65.8
100.6
30.0
Baymag
1.05
0.65
48.8%
30
6
67.5
91.9
20.0
Baymag
1.05
1.00
48.8%
30
7
40.5
120.8
40.0
Baymag
1.50
0.30
40.0%
30
8
54.9
119.8
25.0
Baymag
1.50
0.65
40.0%
30
9
67.5
131.3
20.0
Baymag
1.50
1.00
40.0%
30
10*
65.8
100.6
30.0
Baymag
1.05
0.65
48.8%
30
Totals
596.8
315.0
“m” refers to the molar ratio of KH 2 PO 4 to MgO
*repeat of 5
[0000]
TABLE 7
Sag Chamber Testing Data Sorted by Water/Solids Ratio
Final
Position
Net
Net
Final
Relative
Dried
Dried
Total
to a
Coating
Coating
Calculated
Ratio of
Move-
Flat
Sample
Weight
Weight
“m”
Water to
ment
Plane
Name
(g/panel)
(g/sf)
Value
Solids
(in)
(in)
1
19.3
38.5
0.30
0.60
0.247
0.484
2
29.9
59.9
0.65
0.60
0.202
0.306
3
29.7
59.5
1.00
0.60
1.136
1.212
4
11.9
23.8
0.30
1.05
0.458
0.597
5
14.9
29.7
0.65
1.05
0.491
0.594
10
28.6
57.2
0.65
1.05
0.658
0.768
6
14
27.78
1.00
1.05
0.809
0.868
7
13
25.34
0.30
1.50
0.526
0.647
8
17
33.22
0.65
1.50
1.295
1.363
9
18
36.50
1.00
1.50
1.735
1.809
11
na
0.0
0.00
0.00
2.262
2.255
12
na
0.0
0.00
0.00
2.271
2.268
13
na
0.0
0.00
0.00
2.231
2.212
14
na
0.0
0.00
0.00
2.193
2.202
15
na
0.0
0.00
0.00
2.200
2.180
[0000]
TABLE 8
Wt. of
Wt. of
Wt. of
Ml of 85%
calc.
calc.
Trial #
MgO
KH 2 PO 4
Water
H 3 PO 4
pH
“m”
W/S
1
10.0
10.0
10.0
0.0
3.17
0.30
0.50
2
10.0
10.0
10.0
0.1
1.59
0.30
0.50
3
10.0
10.0
10.0
0.5
1.25
0.30
0.50
4
10.0
10.0
5.0
0.5
1.25
0.30
0.25
“m” refers to the molar ratio of KH 2 PO 4 to MgO
W/S refers to the water to solids ratio. | Methods for making building panels are described. The methods include combining water, an inorganic fiber, and one or more binders to form a slurry, wherein at least one of the binders comprises starch; shaping the slurry into a panel; applying a coating to a back side of the panel, the coating comprising a reaction product of magnesium oxide and a phosphate salt in the absence of an amino alcohol; and drying the panel. Building panels are also described. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of U.S. patent application Ser. No. 10/837,958 filed May 3, 2004.
STATEMENT CONCERNING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
FIELD OF THE INVENTION
This invention relates generally to construction castings, and more particularly to manhole, grate, catch basin, trench drain and hatch assemblies for covering openings and access points (hereinafter “covers”).
BACKGROUND OF THE INVENTION
Typically, manholes and other types of hatches must be covered either fully or partially (as with a grate) because they are needed in places where they are crossed over by pedestrians, cars, trucks, and even aircraft. Some of these manholes and hatches have hinged covers that can be conveniently opened and closed. Unlike non-hinged covers, hinged covers cannot become partially unseated as can happen with a sewer surcharge. Hinged covers may also be opened more easily than non-hinged covers.
One type of hinged cover is shown in Defrance et al., U.S. Pat. No. 4,840,514. Defrance discloses a manhole assembly having a lid that is hinged to a frame with a T-shaped lug. There are two principal disadvantages to this particular construction. First, in order to remove or replace the cover itself, something that is periodically necessary, an operator has to be able to lift the cover straight up to release it from the position in which it is held open. Given the weight and size of most such covers, this is a particularly difficult task. Second, these hinged covers cannot be lifted with ordinary levers thus requiring the application of brute force.
Another type of hinged cover is shown in a European Patent Office publication for Saint-Gobain PAM, EP 1160382. This hinged cover locks by dropping a lug down into a hinge receptor, requiring one to lift the cover before it can be lowered. This causes the user to lift the weight of the cover each time it is used, even when the cover is not removed from the frame.
Like manhole and hatch assemblies, trench drain grates and solid covers are used in places where they are crossed over by pedestrians, cars, trucks, and even aircraft, and are not easily accessed. Trench drain and grate covers fit into a frame that typically spans the width of a driveway or other area where drainage or ventilation is desirable. Frequently, it is necessary to fasten these grates and covers to the frames. In usual applications, each separate cover is bolted to the frame with a number of bolts—typically one in each corner or otherwise fastened with one of many types of an internal mechanical locking device. If one desires access to the trench or drain below the cover, each bolt must be removed or the mechanical locking device released so the cover can be lifted and removed. Lid removal is time consuming and sometimes difficult due to damaged bolts, broken mechanical locking devices or dirt. In addition, bolt patterns and mechanical lifting devices may change due to wear, and it may be difficult to replace the removed lids if they do not have the same orientation as they did prior to removal.
Accordingly, there is a well established need for a connector used in conjunction with various construction castings that is simple and easy to use and maintain. Because construction castings are typically heavy, there is a further need for construction castings that are more ergonomic for lid or cover opening and removal.
SUMMARY OF THE INVENTION
The present invention overcomes many of the drawbacks and disadvantages of the prior art. It includes a hinge construction that is simple and easy to manufacture. Moreover, covers made in accordance with the present invention can be lifted with a lever, thus greatly reducing the amount of lifting force required to open the cover. As a result of the hinge design of the present invention, covers can be readily removed from the hinge receptor, facilitating easy removal and replacement, without the use of tools.
The joint is used in a construction casting assembly. This joint may have certain features that limit the movement of a cover with respect to a frame. In another aspect of the invention, the joint is used to connect grates or trench-type drains in series. Generally, the grates are connected end-to-end and use relatively few bolts to lock the grates to a frame. In yet another aspect of the invention, the joint is used again to connect grates or trenches to a frame. Rather than linking each cover or grate together, each grate is instead independently connected to the frame. For example, a ball head extends from each grate that, in turn, fits into a corresponding socket of the frame.
Various other features, objects, and advantages of the invention will be made apparent to those skilled in the art from the following detailed description including illustrative examples setting forth how to make and use the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a manhole frame and cover connected with a ball and socket joint of the present invention;
FIG. 1 a is a perspective view of the manhole cover of FIG. 1 , the cover shown separately from the frame;
FIG. 1 b is a perspective view of the manhole frame of FIG. 1 , the frame shown separately from the cover;
FIG. 1 c is a perspective view of the latch shown in FIG. 1 ;
FIG. 2 is the manhole frame and cover of FIG. 1 , with the cover locked in an open position;
FIG. 3 is a side elevational view of the manhole frame and cover and hold open safety device of FIG. 2 ;
FIG. 4 is a partial cross-sectional view of the socket located in the manhole frame of FIG. 2 , taken at line 4 — 4 ;
FIG. 5 is a partial cross-sectional view showing how a ball extending from the manhole cover fits within the socket shown in FIG. 4 ;
FIG. 6 is a perspective view of the manhole cover and frame of FIG. 2 , with the cover turned 90 degrees;
FIG. 7 is a perspective view of a pair of grate covers with the ball and socket joint of the present invention, the covers joined in series and the frame partially cut away;
FIG. 8 is a perspective view of the grate covers of FIG. 8 showing a cover in a raised position;
FIG. 9 is a perspective view of the grate covers of FIG. 9 , showing the raised cover of FIG. 8 turned so that it may be detached from another cover;
FIG. 10 is a perspective view of the cover of FIG. 8 being separated from another cover;
FIG. 11 is a top plan view of a series of end to end grate covers using another embodiment of the invention, wherein each grate cover is connected to a frame;
FIG. 12 is a view like FIG. 7 of trench grates but showing the heads with bosses and fins and corresponding sockets;
FIG. 13 is a view like FIG. 8 but of the trench grates of FIG. 12 , with one of the grates hinged up 90 degrees about a horizontal axis;
FIG. 14 is a view like FIG. 13 showing the hinged up cover turned by 90 degrees about a vertical axis;
FIG. 15 is a view of the raised and turned cover lifted out of the socket of the other cover;
FIG. 16 is a view like FIG. 11 of trench grates with heads each having bosses and a fin and corresponding sockets in the frame;
FIG. 17 is a view like FIG. 16 illustrating another embodiment of end to end trench grate covers supported by a frame made up of frame sections;
FIG. 18 is a detail view of sections of the cover assembly of FIG. 17 ;
FIG. 19 is a partial cross-sectional view from the plane of the line 19 — 19 of FIG. 18 ;
FIG. 20 is a view like FIG. 19 but with the cover open;
FIG. 20A is a detail view of the area 20 A— 20 A of FIG. 20 ;
FIG. 21 is a top perspective view of a different embodiment of a trench grate cover by itself;
FIG. 22 is an end view from the plane of the line 22 — 22 of FIG. 21 ;
FIG. 23 is a cross-sectional view of the socket portion of the frame;
FIG. 24 is a detail cross-sctional view of the area 24 — 24 of FIG. 19 ;
FIG. 25 is a view like FIG. 24 but showing the cover open;
FIG. 26 is a view of a single trench grate assembly; and
FIG. 27 is a cross-sectional view from the plane of the line 27 — 27 of FIG. 26 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring FIGS. 1–1 b , the present invention comprises a relatively simple hinge, cover and frame assembly 10 . As can be seen, a cover 12 is connected to a frame 14 by a hinge subassembly or “joint” 16 , such that cover 12 is seated in frame 14 when the cover 12 is in a closed position. As shown in FIG. 5 , joint 16 is generally constructed in a ball and socket arrangement. Depending upon the particular type of cover and frame, and the degree of security necessary in the connection of the cover to the frame, different embodiments of joint 16 may be employed. Preferably, joint 16 is constructed so as to permit removal of a cover 12 from a frame 14 without tools. As will be described more fully herein, such removal may be accomplished by merely opening the cover 12 to its open position, turing it 90 degrees, and lifting it out. Each action is performed separately and can be done manually or with a lifting device, if desired.
Referring to FIGS. 1 a and 5 , joint 16 has a first piece that includes a ball-shaped head 18 that is preferably connected to another structure such as cover 12 . Generally, the ball-shaped head 18 will be connected to cover 12 (or other cover as described herein) via a neck portion 20 or the like. As seen in FIGS. 1 b and 4 , head 18 fits into a socket 22 that is generally defined by a wall or surface 23 shaped to conform around the head 18 . Other features may be added to joint 16 to enhance its functionality.
One such feature, present in one preferred embodiment of the invention, is the modification of head 18 in a shape that is not a perfect sphere. Instead, the head 18 has a pair of parallel, flat, planar faces 24 positioned in symmetric, spaced apart relation to one another. In other embodiments of the present invention, the faces 24 may have concave and/or embossed surfaces. In these embodiments, a collar 26 is positioned above socket 22 and is constructed to correspond to the faces 24 . As shown in FIG. 1 , where the head is constructed with the pair of flat faces 24 , the collar is 26 preferably defined by a pair of straight portions 30 connected by an arc-shaped portion 32 . The collar 26 has an open end located opposite arc shaped portion 32 to accommodate neck portion 20 when the cover 12 is in a closed position. Collar straight portions 30 are parallel and spaced apart at a distance in excess of the distance between the two flat faces 24 . When head 18 is oriented so that faces 24 are substantially parallel with the inside edges of straight portions 30 , head 18 fits between the straight portions 30 so that the head 18 can be inserted into socket 22 . As can be seen in FIG. 6 , when head 18 is fit between straight portions 30 , cover 12 is sideways such that it cannot be lowered so as to achieve a closed position on frame 14 . As seen in FIG. 2 , when cover 12 is rotated through 90 degrees so that the cover is in its normal open position, head 18 is also rotated such that flat faces 24 are perpendicular to straight portions 30 . In this position, cover 12 cannot be removed from frame 14 because collar 26 restrains the head 18 . Removal is not possible since the width of the head 18 in this position is wider than the space between the two collar straight portions 30 . Thus, faces 24 and collar 26 operate to prevent the accidental release of head 18 from socket 22 .
A second feature that may be incorporated in joint 16 is one or more bosses. See FIG. 5 . In a preferred embodiment of the invention, a pair of cylindrical bosses 36 are positioned symmetrically on a common rotational axis that is centrally located between faces 24 . When present, the bosses 36 fit into a groove 38 that runs horizontally below the top of the collar 26 . Referring to FIG. 4 , groove 38 bisects socket 22 , and has a depth and height so that it can slidingly accommodate bosses 36 . Thus, the cooperation between the bosses 36 and the groove 38 provide further resistance to the separation of the cover 12 from the frame 14 when the cover 12 is in its operational or deployed position. In order to permit the removal of cover 12 from the frame 14 , a vertical slot 40 that is centrally located on the collar arc 32 is provided. When the cover 12 is rotated 90 degrees to its removal position, one of the bosses 36 will fit to the slot 40 , such that the head 18 can be extracted from the collar 26 . When head 18 is inserted (or re-inserted) into the socket 22 , a boss 36 slides through slot 40 until it reaches groove 38 . At that point, head 18 can be twisted about the neck 20 axis so that bosses 36 slide within groove 38 . It should be noted that slot 40 can terminate at groove 38 , or extend below it. The slot's termination depends on the desired degree of lateral movement when the cover 12 is in its removal (or re-insertion) position or on the use of certain other features, as described below. Together, bosses 36 and groove 38 serve to restrict the movement of neck 20 (and any structure attached thereto). Within these restrictions, neck 20 may be twisted 360 degrees when oriented in a substantially vertical position, and neck 20 may rotate about bosses 36 when the bosses 36 are perpendicular to edges 30 .
A third feature that may be incorporated into joint 16 is a guiding fin 42 . Referring to FIG. 5 , in accordance with another preferred embodiment of the present invention, fin 42 is a member that extends from the surface 44 of the head 18 directly opposite neck 20 . The purpose of fin 42 is to restrict the movement of the cover 12 when moving from a generally vertical (open) position (see FIG. 3 ), to a horizontal (closed) position (see FIG. 1 ), through a single plane of rotation. Without the fin 42 , the cover 12 could rotate during opening. Given the size and weight of the typical lid or grate used to cover manholes and the like, excessive rotation of the lid during opening could be dangerous and/or damaging. Preferably, the width of fin 42 matches the width of head 18 between the two faces 24 such that the two ends 46 of the fin 42 are flush with each of the faces 24 . Also preferably, the shape of fin 42 follows the overall spherical shape of head 18 such that the back edge 48 of the fin has an arcuate shape. The back edge 48 of fin 42 is dimensioned to fit in the portion of vertical slot 40 which is extended below groove 38 . In this embodiment, when the cover 12 is raised or lowered, the fin 42 moves within slot 40 .
Most preferably, the assembly shown in FIGS. 1–6 includes the three features described above, namely fin 42 , bosses 36 , faces 24 and their corresponding slots and grooves. The frame 14 and cover 12 of assembly 10 need not be round or solid. Frame 14 and cover 12 may be rectangular (such as a hatch), slotted (such as a grate) or any other shape that fits the particular application for which a hinged cover is appropriate. In the preferred embodiment of assembly 10 , frame 14 has an external annular flange 50 from which rises a substantially cylindrical wall 52 . It should be noted that external annular flange 50 can be located anywhere on wall 52 , including around the top of the wall 52 , depending upon the application for which the assembly is intended. An inner flange 54 extends from the inner surface 56 of wall 52 . Flange 54 provides a surface on which cover 12 rests when cover 12 is in a closed position.
In the preferred embodiment of assembly 10 , joint 16 fits substantially within a housing station 60 that extends outwardly from wall 52 . Socket 22 is formed and resides within the housing station 60 such that its receipt of head 18 maintains the cover 12 in a substantially horizontal position as it rests, in its closed position, on inner flange 54 .
In another preferred embodiment of assembly 10 , a cover latch 62 is included. The purpose of latch 62 is to selectively lock cover 12 in an open position. Latch 62 operates in such a way that the operator need not substantially lift the cover 12 to a more open position in order to close it. As best seen in FIG. 1 c , latch 62 may be made from a metal bar having a main body 64 . Referring to FIGS. 2 and 3 , the proximal end of body 64 is pivotally fastened to cover 12 with a hinge assembly 66 . The body 64 has a distal end 68 that selectively contacts the flange 54 when cover 12 is fully open. Preferably, distal end 68 has a bottom surface 69 that is configured to rest squarely on flange 54 . This can be accomplished by angling the lower portion of body 64 resulting in a bottom surface that is at about 90 degrees to the angled lower body or by angling the bottom surface itself at an appropriate obtuse angle relative to the body 64 . Optionally, a boss 71 may be located on surface 69 adjacent the outermost edge of body 64 . Boss 71 overhangs the frame flange 54 . In addition, latch 62 may have an aperture 67 that extends through body 64 . To close cover 12 , aperture 67 may be hooked by a device that pulls the latch away from flange 54 .
When cover 12 is in a closed position as shown in FIG. 1 , and the assembly 10 is intended for use as a manhole cover in a street or other thoroughfare, it is preferred to have the top surface 70 of cover 12 , the ball-head face 24 , and the top surface 72 of housing station 60 in substantially flush relation. This makes travel over the manhole assembly much smoother than if these components were not flush. Of course, it is common practice to emboss any top surface of a construction casting such as manhole assembly 10 to denote source of manufacturer, denote location of manhole, or to provide aesthetic value and/or a safety feature.
In operation, assembly 10 can be easily assembled and disassembled. After frame 14 is placed into a roadway or other structure, cover 12 is oriented in a position approximately 90 degrees from its normal open position as shown in FIG. 6 . Head 18 is then aligned between straight portions 30 and inserted into socket 22 . Once in place, the cover 12 is rotated approximately 90 degrees to its normal open position. In the open position, if present, latch 62 can be used to maintain the cover 12 in place. The cover 12 is closed by disengaging latch 62 and seating cover 12 within the frame 14 on inner flange 54 . To remove cover 12 , the process is reversed.
Referring to FIGS. 7–16 , in another embodiment of the present invention, a ball and socket joint 16 may be used in connection with a series of covers in the form of grates covering trench drain or the like. The grates 80 used to cover an elongated drain or opening are aligned in series and seated into a frame 82 . Generally, each grate 80 connects end-to-end as shown in FIGS. 7–10 and 12 – 15 . Alternatively, the grates 80 could connect to the frame 82 , as shown in FIGS. 11 and 16 .
As seen in FIGS. 7–10 and 12 – 15 , each grate 80 has a socket 84 in a first end and a ball head 86 at the opposite end that is connected to the grate 80 via neck portion 88 . Specifically, grate 80 may be an elongated rectangular shape as shown. Preferably, a socket 84 is located centrally at one end of each grate 80 . The socket does not have to be centered, but the central location of socket 84 makes assembly easier. As seen in FIGS. 8 and 13 , socket 84 is defined, at least in part, by a U-shaped notch 90 . Preferably U-shaped notch 90 includes a depression 92 that it conforms to the mostly spherical shape of ball head 86 . Located on the opposite end of grate 80 is head 86 . Like socket 84 , head 86 is preferably aligned with the longitudinal axis of grate 80 . As with prior embodiments, head 86 has a pair of opposite faces 93 . Faces 93 preferably lie in the same plane as grate surface 94 so that pedestrians and vehicles will experience a relatively smooth surface. However, as in other embodiments, faces 93 may be embossed or the like.
Also as with prior embodiments, head 86 can include a pair of cylindrical bosses 104 that are positioned symmetrically on a common rotational axis that is centrally located between faces 93 . When present, the bosses 104 fit into a groove 106 in the notch 90 of socket 84 . Groove 106 bisects socket 84 , and has a depth and height so that it can slidingly accommodate bosses 104 . The cooperation between the bosses 104 and the groove 106 thus provides further resistance to the separation of the grates 80 . Vertical slot 108 allows for the removal of one grate 80 from another grate 80 . Like in other embodiments, when one grate 80 is rotated 90° to its removal position, one of the bosses 104 will fit to the slot 108 , such that the head 86 can be extracted from the socket 84 . As well, when head 86 is inserted (or re-inserted) into the socket 84 , a boss 104 slides through slot 108 until it reaches groove 106 . At that point, head 86 can be twisted about the neck 88 axis so that bosses 104 slide within groove 106 . Bosses 104 and groove 106 thus together restrict the movement of neck 88 (and any structure attached thereto), as described above for other embodiments.
Also as previously described, joint 16 can also include a guiding fin 112 . Fin 112 is a member that extends from the head 18 directly opposite neck 88 . The purpose of fin 112 is to restrict the movement of the grate 80 when moving from a generally vertical (open) position (see FIGS. 8 and 13 ), to a horizontal (closed) position (see FIGS. 7 and 12 ), through a single plane of rotation. Without the fin 112 , the grate 80 could rotate during opening, which, as noted above, could be dangerous and/or damaging given the weight of the typical grate. The width of fin 112 , as in other embodiments, preferably matches the width of head 86 between the two faces 93 such that the ends of the fin 112 are flush with each of the faces 93 . As well, the shape of fin 112 preferably follows the overall spherical shape of head 86 such that the back edge 114 of the fin 112 has an arcuate shape, and the back edge 114 of fin 112 is dimensioned to fit in the portion of vertical slot 108 which is extended below groove 106 . When using fin 112 , when the grate 80 is raised or lowered, the fin 112 moves within slot 108 .
The frame 82 is generally an elongated rectangular frame into which a series of grates 80 may be fitted. The last grate 80 to be placed in the series may be bolted to frame 82 , such as shown in FIG. 7 at corners 96 . Further, on the last grate 80 , the socket 84 may be omitted if desired. The first grate 80 of a series may also be bolted to frame 82 at its two outermost corners. Alternatively, the frame may have a head 86 or socket 84 located at one end so that the first grate 80 of a series may be connected to the frame 82 by the joint of the present invention rather than a pair of bolts. In addition, a pair of centrally located grates may be bolted down on abutting edges rather than be joined by a joint of the present invention. Alternatively, a central grate could be used as one of the grates between the end grates that had sockets in both ends, to end up with socket ends of the grates at both ends of the trench, at which ends the sockets may be omitted if desired.
In use, a first grate 80 is fit into frame 82 . Consecutive grates 80 may be linked to the first until the frame is completely covered by grates 80 . Preferably, the first and last grates 80 are bolted to frame 82 at their outermost corners. Removal of the grates 80 from frame 82 is demonstrated in FIGS. 8–10 and 13 – 15 . In FIGS. 8 and 13 , a grate 80 is lifted from a horizontal (closed) position to a vertical upright (open) position. In FIGS. 9 and 14 , the upright grate 80 is twisted 90 degrees. In FIGS. 10 and 15 , the upright grate 80 can be removed by pulling it straight upward. This is repeated until the desired number of grates have been removed. As in the prior embodiment, the head 86 cannot be removed from frame 82 until the head faces 93 are parallel to the opposite edges 94 of socket 84 .
In yet another embodiment of the present invention, shown in FIGS. 11 and 16 , the configuration of sockets and heads are identical to sockets 84 and heads 86 in the previous embodiment. However, in this embodiment, the location of the sockets and heads is different. Rather than connecting the grates 80 in series, each grate 80 a is independently connected to frame 82 a . Preferably, a socket 84 a is located in frame 82 a , and a corresponding head 86 a is located on each grate 80 a . Any grate 80 a may be independently inserted and removed from frame 82 a in a manner similar to that of the previous two embodiments. The grate may also be fastened to frame 82 a so that it cannot be accidentally removed. For example, the side of grate 80 a located opposite of head 86 a may be fastened with a bolt or bolts 102 .
The grates 80 , 80 a and 80 b are shown in FIGS. 7–11 with a series of drainage outlets 100 . However, such grates could have a solid surface or differently configured outlets 100 . In addition, there are only two or four grates 80 shown in FIGS. 7–11 . Any number of grates may be lined up in series.
In the embodiment 210 of FIGS. 17–25 , the arrangement of FIGS. 11 and 16 is used in which the necks 212 and enlarged heads 214 of the hinge joint extend from the sides of the grates 220 and are received in sockets 218 in the frame 224 . In this embodiment, the frame 224 is made up of frame sections 226 which may or may not be bolted together by bolts 230 . The construction of the enlarged heads, necks and sockets may be as described above, having bosses 232 , fins 234 and the socket shapes that conform to the bosses 232 and fins 234 . In addition, a latch 240 may be provided on each cover, so the whole trench can be opened and held open. As illustrated in FIG. 21 , each cover may be provided with a handle or lifting recess 244 , in which a lever or pry bar may be inserted to assist in opening the cover and closing it.
FIGS. 26 and 27 illustrate a cover 220 like in FIGS. 17–25 , but by itself in an individual frame 240 .
While the invention has been described with reference to preferred embodiments, those skilled in the art will appreciate that certain substitutions, alterations, and omissions may be made without departing from the spirit of the invention. Accordingly, the foregoing description is meant to be exemplary only and should not limit the scope of the invention set forth in the following claims. | A joint suitable for construction castings having a frame and a lid or cover, such as manholes, grates, trench drains, hatches and the like, and construction castings incorporating the same. No tools are necessary to separate the joint. An enlarged head located on a cover fits into a socket located on a frame or adjacent lid. To separate the head from the socket, the lid is lifted to a substantially vertical position and turned about ninety degrees. The lid can then be lifted away from the socket. When the joint is used in manhole or hatch assemblies, a latch may be used to hold the cover open and the cover may be opened and closed with a lever. | 8 |
BACKGROUND OF THE INVENTION
[0001] Staircases or a set of steps are used to walk from one elevation to another elevation. While steps have been around for so long that no one can say for sure about the first set of steps, one can only imagine that the first set of steps were probable stones stacked upon one another. As time went on, ways to attach the stones more permanently to one another were developed. Even before the invention of modern cement, evidence exists that ancient civilizations used certain materials to “mortar” stones together to form a set of steps. Even before blades were used to cut trees into lumber, logs were shaped into flat steps and attached to make a staircase. Not long after iron and steel were developed, they too were soon used to fabricate a set of steps.
[0002] Whatever the method used by the ancient civilizations, the method of constructing a staircase was always the same. They would gather the raw materials they were going to use and take them to the site where they were going to use them then they would fabricate the staircase using one piece at a time. This method is the most commonly used method still to this day. It usually involves bringing boards, cutting them and nailing them together or using masonry blocks, or stone, or bricks and mortaring them together. Another commonly used method today involves forming a staircase out of wood or like material and pouring concrete to take the shape of a staircase.
[0003] While a set of steps fabricated in these ways can be very beautiful and elaborate, they can also be very expensive. To make a set of steps in stone or brick is beyond the know-how of the typical homeowner and a professional mason has to be hired. Also because steps done in this fashion are stone or bricks cemented together into one large piece, these types set of steps has to be placed on a footing. If a footing were not used, any settling or shifting would cause this one large piece to crack.
[0004] To custom build a set of steps one piece at a time is not the only way to build a set of steps however, “prefabricated” steps are known in the art. “Prefabricated” staircases are built in a factory or some other location and then taken to a site where they are typically attached to the upper and lower elevations. Interior wooden staircases are the most common of these and are widely used today. Exterior staircases made of pressure treated lumber are also used. Prefabricated steel steps are commonly used for fire escapes and the like. U.S. Pat. No. 4,438,608, U.S. Pat. No. 4,802,320, and U.S. Pat. No. 4,899,504 are types of these. While prefabricated interior staircase can be very decorative and elaborate, most types of these materials can't stand up to the elements when used in the exterior.
[0005] One type of prefabricated steps that can stand up to the elements is a prefabricated concrete unit. The problem with this is that they are make of solid concrete and have to be set in place by a mechanical lift of some sort. Making it impractical for installation in some locations.
[0006] One way to solve the problems that large and heavy prefabricated units present is by developing pre-made parts specifically designed for use as a stair or staircase. Most people can assemble stair parts like these without costly professional help. While precut parts used to make a set of steps can be purchased at any local home building materials store, most are out of lumber or metal not out of masonry that can be long lasting when used in the exterior.
[0007] There are methods using some sort of block that is stacked one upon another, known in the art. Some have means of interlocking and can even be assembled without “mortaring” the blocks together. In U.S. Pat. No. 6,295,772, U.S. Pat. No. 6,176,049 and U.S. Pat. No. 5,479,746 are examples of types of masonry block that are used almost exclusively for making steps.
[0008] Recently steps have been make using split faced masonry block, U.S. Pat. No. 4,802,320 and U.S. Pat. No. 5,017,049 are examples of these blocks and can be glued together with a masonry adhesive to form a set of steps. This method allows the staircase to “give”, thereby preventing cracking. The appearance of this type of staircase is limited because of the way these blocks are manufactured. Also, any method used to build a set of steps out of blocks stacked one upon another requires the use of many blocks, not only on the outside and front face but also the totality of the inside from the ground up to the top and from side to side.
[0009] It has been known for some time in the art to build masonry steps for outdoor use using materials other than stacked blocks. U.S. Pat. No. 5,014,475, U.S. Pat. No. 4,959,935, U.S. Pat. No. 4,406,347, U.S. Pat. No. 4,250,672, and U.S. Pat. No. 4,244,154 all have masonry pieces that don't require the total area under the step treads to be built up. All these methods use a stringer type design for the risers. The trouble with a stringer design is a different sized stringer would be used for staircases with different numbers of steps. This would present a problem to supply stores that would have to carry inventories for one step units, different stringers for two step units, and so on.
[0010] U.S. Pat. No. 1,879,996, U.S. Pat. No. 2,697,931, U.S. Pat. No. 2,722,823, U.S. Pat. No. 3,025,639, U.S. Pat. No. 3,706,170 all have solid side pieces not stringers, that serve as risers. While these staircase systems also don't require the total area under the step tread to be built up, they have the same problem in that supply houses would have to carry different side ieces for each set of differing numbers of steps. These large inventories are very costly and inconvenient.
[0011] U.S. Pat. No. 2,374,905 has masonry pieces stacked upon one another not solid side pieces. But this system talks of poured concrete key-ways, thereby presenting the same problem of cracking that any solid masonry staircase would present.
[0012] It would therefore be a significant advance of the art to provide a staircase or set of steps made out of long lasting masonry pieces which could take on the appearance of natural stone or brick. And which could be easily assembled using just nuts and bolts, without having to pour footings or “cement” these pieces together. It would also be an advance in the art if these masonry pieces could be easy to handle and assembled in such a way as to use as few pieces as possible in the construction of the staircase. It would be a further advance in the art to develop a system to produce exterior staircases that could be used to build steps of differing numbers of steps and steps of differing widths using interchangeable parts. And at the same time being able to inventory only small amounts of system pieces to do this.
BRIEF SUMMARY OF THE INVENTION
[0013] The present invention is generally directed to an exterior staircase or set of steps made from pre-manufactured masonry and steel pieces. These pieces can be easily assembled to produce a long lasting set of steps.
[0014] In particular one object of the invention is to use pieces that are light enough to be handled by hand and can be connected together on site.
[0015] Another object is to use decorative, preformed in molds, manufactured pieces. These pieces would be pre-sized and fined to go together in such a way as to form a set of steps.
[0016] Another object of the present invention is to put these pieces together so they are not cemented together.
[0017] Another object is to use specific pieces for specific parts of the step. I.e. the sides of a 3-step unit will have 3 courses for each side. While the pieces that form these courses are interchangeable from left side to right side, they are different sizes for each different step. The bottom course being a masonry piece or multiple pieces that are longer than the course above it and the one above that being shorter still.
[0018] Another object is to use side pieces that can be used on either the right side or the left side risers, and use the same front pieces for the first step, second step, third step and so on. The front pieces are interchangeable with other front pieces of the same width step, but not interchangeable with other steps of different widths or any side pieces.
[0019] Another object is to use different front pieces (longer or shorter), attached to the same side pieces, in order to construct different widths of steps.
[0020] Another object is to use masonry pieces for the bottom step that are a different height than the ones used for the remaining steps.
[0021] Another object is to use masonry pieces that are formed with embedded bolts or other securing devices, so they can be attached.
[0022] Another object of the invention is to use a rigid frame that can act as the securing device for the masonry units. And to have this frame constructed in such a way as to allow for all courses of the side risers to be stacked one upon another and connected to each other, while at the same time allowing multiple pieces to be used for each course, if necessary.
[0023] Also, another object of the invention is to have this frame able to connect the right side risers to he left side risers and both sides to the front riser pieces.
[0024] Another object is to allow for limestone or other natural stone treads to be placed and secured into the unit and act as the actual step.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0025] [0025]FIG. 1 is a perspective view of a three-step unit of the present invention showing the masonry side and front pieces as well as the treads.
[0026] [0026]FIG. 2 is a perspective view showing a top left riser side and a top right riser side of a step unit.
[0027] [0027]FIG. 3 is a perspective view showing a left front riser and a right front riser of a step unit.
[0028] [0028]FIG. 4 is a perspective view showing a mold that a side riser piece is formed in.
[0029] [0029]FIG. 5 is a perspective view showing the metal frame parts of a three-step unit.
[0030] [0030]FIG. 6 is a side plane view showing the metal frames, front riser pieces, and stone treads of a three-step unit.
DETAILED DESCRIPTION OF THE INVENTION
[0031] In FIG. 1, masonry pieces are different sizes. Top left riser 1 rests on top of left middle riser 2 , which rests on the top of left bottom riser 3 . The bottom of left bottom riser 3 rests on the ground. Riser 3 is of a different height than riser 2 & riser 1 . According to most building codes, typically a step is 7½″-8″ high. From the ground, the top of the first step should be 7½″. The stone slabs are commonly used in other step applications and are typically 2″ in thickness. The stone slab 13 rests on top of left bottom riser 3 and right bottom riser 4 . Since the slap is already 2″, the height of the bottom pieces 3 and 4 should be 5½″ to bring the height of the bottom step to 7½″. The second stone slab 14 is the second step. The second stone slab 14 rests on the top of left middle riser 2 and right middle riser 5 . The height distance from stone slabs 13 to the stone slab 14 should be 7½″. Side riser 2 rests on top of side 3 , but the bottom of side 2 is the thickness of stone slab 13 or 2″ lower than the top of the first step 13 . Therefore, to get the 7½″ step height the height of side 2 is 7½″. The height from stone slab 14 to stone slab 13 is 7½″. Side 1 rests on top of side 2 . The bottom of side 1 is 2″ lower than the bottom of the second step. Therefore, the height of the side 1 is 7½″. With the stone slabs resting on the tops of the side pieces and the next ascending side pieces resting on the side piece below it, any side piece after the first step will be 7½″ high. This will follow from step 2 to step 3 to step 4 and beyond. The bottom sidepiece will always be 5½″ in height.
[0032] Top left riser 1 is a certain width, in this instance x. The width x of side riser 2 is twice that of side riser 1 and that is 2×. The width of side riser 3 is three times the width of side riser 1 and that is 3×. Increasing numbers of steps have lengths that have similar increasing multiples of side riser 1 .
[0033] [0033]FIG. 2 shows both left top riser 1 and right top riser 4 . Both pieces have six sides and are the same dimensions. The bolts 54 are in the middle, from top to bottom, of side riser 1 . Decorative face 33 is the outside side of riser land used on the outside of the steps. Top face 18 is the top of riser 1 . When left riser 1 is flipped end for end it is now in the same configuration as right riser 4 with the decorative face 33 being on the outside. The top face 18 is in the bottom side position of right riser 4 . The bolts 54 are still in the middle from top to bottom of riser 4 . All side riser pieces, while having different dimensions, are configured the same and therefore, interchangeable in the same position from left side to right side.
[0034] In FIG. 1, front riser 8 rests between treads 13 and 14 and on top of tread 13 . Since treads are typically 2″, the distance between top of tread 13 and bottom of tread 14 is 5½″. Front riser 8 as well as all other front risers are the same height dimension, typically 5½″. The front risers could be one long piece but long narrow pieces of concrete can easily break during transport. In FIG. 1, front risers are most typically two pieces, left front risers 7 , 8 , and 9 and right front risers 10 , 11 , and 13 Because these pieces have bolts that are placed in the middle of the pieces and equal distance from side to side, they can be flipped end for end and are interchangeable from left side to right side, the same way that side riser-pieces are interchangeable in FIG. 2. Whether it is the first, second, third or any other step, the length of the front riser piece determines the width of the step from side to side. In FIG. 1, the length of the front riser 7 is w. All front risers of the same step unit have risers of equal length. By making the length w of riser 7 longer, the step unit's width, from side to side, becomes wider. In FIG. 1, the top face 18 of the front bottom riser 7 is at the same height elevation as the top face 16 of left side riser 3 and the top face 23 of right side riser 6 . The tops faces of the risers 18 , 16 and 23 provide and area where slab 13 can rest and be affixed with glue to the risers. The bearing weight is transferred, at this point, from the treads to the ground. The top faces of the front risers 19 and 22 allow for the stone tread 13 to rest on top and the bearing weight is transferred to the ground for the first step. In FIG. 1, on the next step the top face 20 of the front riser 8 allow for the stone tread 14 to rest on top of riser 8 . This piece then rests on tread 13 below it, which rests on angle bracket 51 , which is attached to upright center bracket 48 which transfers bearing weight to the ground. All bearing weight from the front of the tread is transferred to the ground in this manner on all subsequent steps.
[0035] All the side pieces and the front pieces have decorative front faces. In FIG. 2, the front face 33 is the outer face of the masonry side riser 4 . In FIG. 3, front riser 10 is decorative on the front face 19 and around the corner at side face 30 . Most decorative masonry blocks are split faced as in (U.S. Pat. No. 4,802,320) or in (U.S. Pat. No. 5,017,049). These blocks are typically made with dry packed concrete. In FIG. 2, because these masonry pieces have embedded bolts 54 & 55 , they are typically made in molds with wet concrete. Because they are made in wet concrete it allows for greater definition of the decorative face. FIG. 4 shows typical mold used to produce masonry side and front pieces, in this case it is a mold for top side riser 4 . Mold 69 is typically rubber or like material, which can be shaped to produce different decorative front faces. The mold allows for five faces of the masonry piece to be formed, with the sixth face formed when concrete is poured into the top of the mold. Decorative face 33 is on bottom of mold. Masonry riser 4 is shown with embedded bolts 54 . These bolts must be embedded at enough of a depth in concrete as to provide for sufficient holding power but must not extend through masonry piece to front face. In FIG. 4, the bolts must also be at precise locations in the wet concrete. The bolts are typically held at precise locations in the wet concrete mold by a bracket 70 and bracket stops 71 which corresponds to the locations of the holes in the steel frame. The bolts 54 must extend out of concrete enough distance to be able to go through pre-drilled holes in metal frame.
[0036] [0036]FIG. 5 shows steel frame. Steel is typically used but any metal, aluminum or rigid material will do. Metal must be primed and painted because metal is exposed to the air. Frames 34 , 35 , 36 , and 37 can be of any rigid material as to allow for distance from side riser pieces 1 , 2 , and 3 to side riser pieces 4 , 5 , and 6 to be held constant. As with the masonry pieces, the steel frames are different sizes for different locations. In FIG. 5, the shapes of the front frames are mostly the same, consisting of a cross bracket, a left upright bracket, a right upright bracket, and a center upright bracket. For frame 36 , the cross bracket is 46 , the left upright bracket is 39 , the right upright bracket is 43 , and the center uprightb bracket is 48 . Center upright bracket 48 also has an angle bracket 51 attached at a 90 degree angle. Frames are the same length for all steps therefore, the cross brackets of all the steps will be the same length. For the next step, the left upright bracket 40 , the right upright bracket 44 , and the center upright bracket 49 are longer in length. As the steps increase, so does the length of the upright brackets. Angle bracket 51 is attached at center upright bracket 49 at a location where it will support the back of the tread. This distance s, down from the top of the cross bracket 46 will be the same on all subsequent steps and all subsequent cross brackets.
[0037] The frame that goes all he way to the back of the step is different from the other frames. This frame 34 consists of a top cross bracket 52 , a bottom cross bracket 53 , a left upright bracket 41 , a right upright bracket 45 , and a center upright bracket 50 . FIG. 5 shows back frame always goes to back of step. The back frame pieces could have pre-drilled holes that would allow four steps to be attached to house or other structure. The upright pieces of the frame are able to connect the masonry piece below to any masonry piece above it. In order for the frames to be able to connect the masonry pieces together, they must have holes to let the bolts that are embedded in the masonry pieces, pass through. In FIG. 2 the bolt holes 61 and 62 are at precise locations in the upright frame bracket 40 that corresponds to the location of bolts in masonry riser pieces. These bolts 54 and 55 can pass thru the bolt holes 61 and 62 and can be secured with nuts or other means. In FIG. 5, left upright bracket 39 connects masonry riser 3 to masonry riser 2 . Upright bracket 40 connects masonry riser 3 to masonry riser 2 and masonry riser 1 . In FIG. 6, this cross bracket 46 is attached to left upright bracket 39 and right upright bracket 43 at 90 degree angles. In FIG. 6, this cross bracket 46 is attached to upright bracket 43 at a point below the top of upright bracket 43 . The bolt 57 embedded in front riser 10 is at a distance y, which is the midpoint of the height of masonry front riser 10 . Therefore, the midpoint of cross bracket 46 is at a distance y down from the top of upright bracket 43 . All front cross brackets are connected to both left and right upright brackets at this distance y from the top of their corresponding brackets. This follows for all steps.
[0038] In FIG. 1, the stone treads 13 , 14 , and 15 may be of natural stone or of a manufactured masonry material. The treads must be of the same thickness so they can be interchangeable and this thickness must be constant. In FIG. 6, the height on front risers 10 , 11 , and 12 are constant, most generally at 5½″. The distance from cross bracket 46 to the steel angle bracket 51 is constant at s. The height of stone tread 13 must be a constant thickness in order to fit under front masonry risers and on top of angle bracket 51 . FIG. 1 shows width of stone tread 13 . This width corresponds to the length of the top riser face 16 that it rests on, plus the width of the top face of the front riser 19 plus an overhang. A one inch overhang is most generally used. The exposed top faces of the risers 2 and 3 are all the same. This distance is x. The front riser top edges are all the same thickness. Therefore, the width of the treads 13 , 14 , and 15 are all the same. The lengths of the stone treads are different for each step units of different widths but are the same for each tread within a given step unit. In FIG. 1 the length of the stone tread 13 corresponds to the length w of the front riser piece 7 plus the length w of the front riser piece 10 . This length of the tread 13 is 2 w. A front riser piece with a longer length w would make for a corresponding longer stone tread 2 w.
[0039] While the above is the preferred embodiment of the invention, many modifications may become apparent to those skilled in the art and these should be considered within the scope and spirit of the invention as defined by the following claims. | A step system made up of masonry panels of various sizes pre-formed to resemble natural stone or brick on the outside. These panels have bolts or other securing devices embedded in them at precise locations at the time of their manufacture. These securing devises allow them to be attached together to form the sides and front of a set of steps. They are attached via a metal frame that is also of differing sizes and made with holes at precise locations to accept the bolts of the masonry pieces. When assembled, as directed, the structure has areas where large slabs of natural stone treads can be rested and attached at differing distances and heights from the ground forming a set of steps. | 4 |
FIELD OF THE INVENTION
The present invention concerns a process for the selective electrofluorination of alloys or metallic mixtures containing uranium in such a way as to be able to recover directly and separately the different components in the form of fluoride and in particular uranium in the form of gaseous hexafluoride.
DESCRIPTION OF RELATED ART
It is an attractive proposition to be able to separate the different components of waste, alloys or metallic mixtures based on uranium, in particular in order to be able to recover the uranium contained therein and its potential content of U235 in the purest possible form.
Hereinafter the term "alloy" will include all metallic mixtures in any form whatever.
For that purpose the applicants have already developed, in patent application FR 92-01730, a process for the fluorination of U-based alloy by reaction of fluorine and/or hydrofluoric acid to obtain "in fine" a mixture of gaseous fluorides containing in particular UF 6 which it is necessary to distil in order to separate the different components and obtain pure UF 6 , whose potential in respect of U235 can thus be re-used in nuclear reactors.
Although that process makes it possible to recover pure uranium under very good conditions, transportation and handling of the gaseous fluorine does however involve risks which it is desirable to be able to avoid. Moreover the distillation of substantial amounts of gaseous fluorides can require installations and delicate management of the operations involved when the proportion of alloyed elements other than uranium is substantial.
That is why the applicants sought to develop a process for the selective fluorination of the various components of the alloy, which makes it possible to avoid handling of gaseous fluorine and to simplify the distillation operations, by limiting the volumes to be treated, which are intended to give the pure components, or even to eliminate such operations.
SUMMARY OF THE INVENTION
The invention is a process for the selective fluorination of alloy or metallic mixture based on uranium characterized by effecting a selective anodic reaction on at least one of the components of the alloy by means of a controlled anodic voltage applied to the alloy in a bath of molten fluorides.
Thus, this involves an anodic oxyfluorination reaction which essentially consists of anodically and selectively fluorinating the components of the alloy, beginning with that which is most electropositive. This process is particularly suitable for the recovery of uranium from alloys, by virtue of the fact that it is generally the most electropositive metal in the alloy; thus, the uranium is generally recovered first in the form UF 6 , and the other metals can then be fluorinated separately one after the other in order to be recovered in accordance with the process of the invention or they may be discharged if recovery thereof does not involve any attraction.
In order to perfect the degree of purity of the UF 6 obtained or the other components of the alloy giving volatile fluorides, it is possible to effect complementary distillation of the anodic gases and/or the electrolysis bath.
The alloy to which the anodic voltage is applied is generally employed in fragmented form and for that reason it is preferable for it to be contained in a basket formed by a material which is resistant to the fluorine-bearing bath under the conditions in respect of voltage of the anodic reaction, it can be in particular based on carbon or Monel metal or certain insulating plastics materials such as polyfluoroethylenes (Teflon) or other perfluorinated plastics materials. The carbon or the carbon fibres which are reinforced by composites which can be rapidly passivated in the presence of fluorine and uranium salts constitute advantageous materials.
In order better to control the reaction, it is advantageous for the basket to be slightly cathodically polarised with respect to the alloy to be treated but of course always being anodically polarised with respect to the cathode; for that purpose, use is made of a metal basket (for example of Monel metal) which is internally covered with plastics material in order to insulate it from the alloy and to be able to maintain its potential at the selected value.
The electrolyte is exclusively based on molten fluorides; it is preferable for the cations to be such that, after reduction of said fluorides, they result in an element which is insoluble or weakly soluble in the bath or which does not react with same or with the anodic compounds obtained.
In that respect it is advantageous that, as fluoride, the electrolyte contains hydrofluoric acid as a regularly added consumable material; its cation, once reduced, does not react with the bath. Thus it is possible to use baths of the type KF-HF containing for example 38 to 45% (by weight) of HF which melts at between 80° and 120° C. such as the bath KF-2HF which melts at about 100° C., or baths of the type NH 4 F-HF containing for example from 45 to 75% (by weight) of HF which melts at between 55 and 80° C., such as the bath NH 4 F-3HF which melts at about 60° C. In that case hydrogen is generated at the cathode and is removed.
The temperature of the electrolysis bath is such that the metallic fluorides generated (including at least UF 6 ) are gaseous and can be easily recovered.
Likewise it is advantageous for the vapour pressure of the electrolyte to be sufficiently low to avoid pollution of the metallic fluoride collected.
The charge of alloy to be treated is set to an anodic potential such that all of the most electropositive metal of the alloy, generally uranium, as already stated above, is firstly fluorinated. The value of that anodic voltage may be within wide limits: it depends not only on the metal to be fluorinated but also the electrolysis bath, the current supply means, the constitution of the charge, the basket, the diaphragms and more generally the whole of the electrolysis equipment used.
The attempt is made to maintain that voltage approximately constant although it is in general necessary to adjust it to take account of the chemical or other variations which occur in the course of reaction in the electrolysis cell and to maintain an adequate production of gaseous fluoride; however, in order to preserve the selectivity of the process, it is then necessary to ensure that it is not at a level such that fluorination of another component of the alloy takes place.
After a first metallic component of the alloy has been ccmpletely fluorinated, the anodic voltage can be increased in such a way as to cause selective fluorination of a second component of the alloy, and so forth, in successive stages. It is also possible however to remove the residual metals if there is no interest in treating them by means of this method or if they give non-volatile fluorides.
It is difficult to determine the density of the anodic surface current used in the course of the process, having regard to the fact that the alloy is in fragmented form. However the applicants have found that it was preferable to operate with a low level of intensity so as to improve the degree of selectivity of the fluorination effect and that the critical parameter was the density of energy dissipated with respect to the volume of the electrolysis bath.
Thus it is possible to use densities of between 1 and 30 A/l of electrolyte, with cathodic densities of from 0.1 to 0.5 A/cm 2 , the local anodic surface densities then being of the order of from 0.001 to 0.01 A/cm 2 , depending on the state of division of the alloy.
In order to feed the anodic current to the metallic charge to be treated, the procedure generally involves using materials which are not consumed or which are consumed only slightly under the conditions of the process and which do not give fluorides which are volatile and/or which are easily passivated. Thus the applicants found that carbon is a choice material as it is automatically passivated in the regions which are remote from the metallic charge, with the probable formation of nascent fluorine.
As regards the cathode, it is generally metallic and formed of steel, nickel or Monel metal and separated from the anodic zone by a diaphragm, for example of the slatted shutter type, which prevents migration of the cation which is reduced in the anodic compartment.
The cathode can also be formed by all or part of the walls of the electrolysis tank; in that case, to prevent hydrogen from being given off on the bottom which is difficult to channel away, it is advantageous to insulate said bottom by a special non-conducting coating or by solidified electrolysis bath.
The tank is generally formed by a cylindrical or parallelepipedic casing, at the centre of which is disposed the anodic compartment with the basket containing the alloy to be treated. It is surmounted by an anodic dome which makes it possible to collect the volatile fluorides generated and possibly cathodic gas collectors for the recovery of hydrogen.
The tank can be insulating or may conduct current and may be for example of coated steel, Monel metal, nickel or plastics material which is resistant to the bath and to the temperature involved and which is preferably reinforced, etc... It is usually closed by a cover supporting the anodic basket with its current feed means and the dome for collecting the gaseous fluorides, the feed of fluoride (for example HF), the electrical connections and possibly the diaphragm, the cathodes and the hydrogen collector. It generally comprises a device (for example a coil) serving for cooling or heating the electrolytic bath with a view to melting it and/or holding it at a temperature.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows an example of the arrangement of an electrolysis cell which is suited to the process according to the invention using a bath containing HF.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference numeral 1 denotes the tank, for example of Monel metal or of steel, internally covered with an inert coating which is resistant to the bath and to the temperature involved, to the walls and the bottom of which are respectively fixed the coils 2 and 3 (or any other equivalent heating or cooling device) which permit regulation of the temperature of the bath or reheating thereof for example after a cooling phase which has resulted in solidification of the bath. In the present case the coil 3 also serves to produce a layer of solidified bath 23 for insulating the bottom.
The cathodic compartment 4 is separated from the rest of the cell (anodic ccmpartment) by means of the diaphragm 5 which is here fixed to the cover 9 and which comprises inclined holes permitting confinement of the hydrogen formed, which is then removed by means of the collector 6. It comprises cathodic plates 7, for example of Monel metal, which are fixed to the cover 9 and which dip into the electrolysis bath, the surface of which is indicated at 8.
An HF feed conduit 20 passes through the cover. The cover is insulated from the bottom of the tank by a Teflon ring 10. The apertured anodic basket 11 which contains the anodic charge 21 is fixed to the cover 9 by way of the Teflon ring 12. It may be of a carbon composite but equally it may also be of Monel metal which is internally covered with a plastics insulating material, Teflon, fluorinated plastics material ... Disposed at the bottom of the basket is a Teflon ring 13 on which rests a carbon disc 14 constituting the lower active part of the anodic current feed means.
The latter therefore comprises the lower disc 14 which is connected to an apertured upper disc 15 (for discharge of the gaseous fluoride produced) by way of a composite carbon rod 16 which is screwthreaded at its ends and protected from the electrolytic bath by an inert and insulating casing 17 for example of Teflon or perfluorinated plastics material ... That arrangement makes it possible to force the current to pass by way of the lower disc 14 so as to preferably to consume the alloy disposed at the bottom of the basket and to cause the gases to percolate through the charge, the feed of that zone with alloy to be consumed then occurring automatically under the effect of gravity.
The upper disc 15 rests on an insulating ring 18 of Teflon which insulates it from the anodic basket 11.
Reference numeral 19 shows the dome which covers the anodic basket and serves to collect the gaseous fluoride formed. It is directly fixed onto the upper disc 15 to ensure good electrical contact which is possibly cooled by the coil 22.
It will be seen moreover that the electrical connection D for supplying the anodic current is directly onto the dome 19 and that the connection K for the feed of cathodic current is directly onto the cover 9 in contact with the cathode 7. The connection P which is connected to the anodic basket serves if necessary to provide for pilot control of and/or to measure the voltage of the basket. Finally the current feed Q serves for pilot control of the potential of the tank 1 to avoid corrosion thereof.
Other arrangements of the cell may be adopted in particular with other types of current feed, for example by means of the walls or the bottom of the tank.
EXAMPLES
The following Examples illustrate the invention.
Example 1
This Example involves effecting fluorination of an alloy U containing 10% of Mo.
The procedure involves using an apparatus corresponding to that shown in FIG. 1. The bath is a mixture of KF, 2HF which is maintained at 100° C., the tank 1 being of steel which is internally covered with a casing of Monel metal. The cathodic plates 7 are of Monel metal and the insulating diaphragm 5 is of Teflon (cloths under the mark GORE-TEX) which is perforated with inclined holes. The anodic basket 11 is of the composite material "Aerolor" (registered trademark of Le Carbone Lorraine), based on bidimensional carbon fibres, and being perforated, and contains pieces of alloy weighing about 50 g.
The anodic current feed ccmprises a lower disc 14 and a connecting rod 16 of graphite while the apertured upper disc 15 of the waggon wheel type is of carbonaceous composite material "Aerolor". The insulating sheath 17 around the rod 16 is of Teflon. The dome 19 is of Monel metal.
The tank and the cathodic plates have been connected together to be at the same potential and the terminal P of the anodic basket was left free to make measurements.
The bath was then melted by circulating through the coils a water-glycol mixture at 120° C., and then cold air was injected into the coil 3 at the bottom of the tank to produce a bottom which is covered with a layer of solidified bath.
A voltage was then applied between the cathodic terminal K and the anodic terminal D, taking into account the selective dissolution voltage of uranium, over-voltages and ohmic losses of the apparatus, in such a way as to give a level of intensity of about 50 A and to have a voltage of 1 V between P and K (anodic basket and cathode), which makes it possible better to control the selective dissolution reaction. The current density is then approximately 0.25 A/cm 2 at the cathodes and is estimated at approximately 0.01 A/cm 2 at the pieces of alloy.
That voltage is maintained approximately constant while however compensating for the Ohmic losses which occur; likewise a regular supply of HF is provided so that the HF content in the bath is constant.
The gases collected were continuously analysed by mass spectrometry; it was found that they were essentially formed by UF 6 with entrained amounts of HF and MoF 5 not exceeding about 0.05%. When the level of intensity fell significantly, it was not possible to increase the voltage to maintain said intensity at an acceptable level without abruptly increasing the proportion of MoF 5 in the gases collected.
That shows that all the uranium was dissolved. The anodic basket (terminal P) was then set to the anodic potential of the terminal D for fluorination of the residues of tetrafluoride UF 4 .
After the electrolysis operation has been stopped, the anodic basket was withdrawn and the residual waste contained therein was neutralised; analysis thereof shows that it then contains practically only molybdenum (proportion of U, 0.01%).
Example 2
This Example involved effecting selective fluorination of a mixture of pieces of U and alloyed steel waste.
The tank 1 of steel used was internally covered with fluorinated polypropylene; it was heated and its temperature was regulated at 60° C. by means of hot air; the bath is formed by a mixture NH 4 F-3HF. The cathodic plates 7 are strips of steel and the anodic basket 11 is also of fluorinated polypropylene; it also acts as a diaphragm to separate the anodic and cathodic compartments, by virtue of inclined holes provided in its wall.
The current feed is such as that described in FIG. 1, the insulating sheath 17 also being of fluorinated polypropylene. The dome 19 is of nickel.
The selective dissolution procedure was carried out in a similar fashion to that described in Example 1.
Bearing in mind that the anodic basket is not conductive, which means it is not possible to control the reaction by way of the potential of the basket, the level of intensity was limited to 20 A; as before the gases collected were continuously analysed.
A UF 6 titrating more than 99.8% was obtained. Its purity could be improved either by stopping the dissolution procedure earlier or by distilling the gas obtained, as already stated.
After electrolysis the metallic residues contained in the anodic basket were treated as in Example 1; they titrate 0.03% of U.
It will be seen that the invention makes it possible to recover practically all of the U from an alloy in such a form that it can be directly used in order to be possibly and easily adjusted, for example by gaseous in-line dilution, to a desired isotopic content, and for the production of nuclear fuels, it being known that, prior to its nuclear use, the uranium recovered can be completely purified by a distillation operation which is easy to carry out. It will also be seen that the process does not give rise to parasitic effluents, and it does not consume reactant and/or energy to react with elements other than the metal to be recovered or reactant for neutralising undesirable effluents. | A process for the selective electrofluorination of metallic alloy based on U characterized by effecting a selective anodic reaction on at least one of the components of the alloy by means of a controlled anodic voltage applied to the alloy in a bath of molten fluorides. | 2 |
The present application claims the benefit of Provisional Application No. 60/670,231, filed on Apr. 12, 2005, the entire contents of which is incorporated herein by reference.
FIELD OF INVENTION
The present invention relates to bi-directional fixating transvertebral (BDFT) screws which can be used to supplement other intervertebral spacers and/or bone fusion materials. BDFT screws can be incorporated into anterior and/or posterior cervical and lumbosacral novel zero-profile horizontal and triangular intervertebral mini-plates. In addition BDFT screws can be incorporated into two dimensional, expansile intervertebral body fusion devices (IBFDs) transforming them into stand-alone posteriorly and/or anteriorly placed cervical, thoracic and lumbar spinal fusion devices. In the lumbosacral and thoracic spine BDFT screws may obviate the need for supplemental pedicle screw fixation. In the cervical spine it obviates the need for supplemental vertically oriented anterior plating. The present invention also relates to a stand-alone or supplemental, calibrating interarticular joint stapling device which can incrementally fine-tune posterior interarticular joint motion.
DESCRIPTION OF THE RELEVANT ART
Segmental spinal fusions which stabilize two or more adjacent segments of the spine are performed for painful degenerative disc disease, recurrent disc herniations, spinal stenosis, spondylolysis and spondylolisthesis. Over the past several decades a wide variety of fusion techniques and instrumentation have evolved. One of the earliest posterior fusion techniques entails non-instrumented in-situ on-lay posteriolateral fusion utilizing autologous iliac crest bone. Because of the high rate of imperfect fusions i.e. pseudoarthroses, transpedicular pedicle screw fixation which utilizes a variety of rods and interconnectors were developed to achieve less interbody motion and hence higher fusion rates. Pedicle screw fixation was initially combined with on-lay posteriolateral fusion. Because of the poor blood supply of the transverse processes, issues still remained with pseudoarthroses. In an attempt to address this problem, pedicle screw fixation has been supplemented with a variety of interbody fusion devices. This is based on the concept that axial loading enhances fusion and that the vertebral endplates have a better blood supply. Interbody lumbar fusion devices can be placed anteriorly via an anterior lumbar interbody fusion technique (ALIF) or posteriorly via a posterior lumbar interbody fusion technique (PLIF). Material options for interbody fusion devices have included autologous iliac crest/laminar bone, cylindrical threaded titanium interbody cages, cylindrical threaded cortical bone dowels, vertebral interbody rings or boxes, carbon fiber cages, or femoral ring allograft. To lessen the complication of prolonged nerve root retraction the technique of circumferential transforaminal lumbar interbody fusion technique (TLIF) has been introduced. This employs the transforaminal placement of an interbody spacer such as one kidney bean shaped allograft, two circular allografts, one or two titanium circular cages, a single titanium or Peek (poly-ether-ketone) boomerang spacer. The threaded spacers are usually supplemented with autologous bone and/or bone morphogenic protein (BMP), demineralized bone matrix (DBM) in the form of paste or cement, rh-BMP with collagen sponges, or similar osteoinductive biological agents which are known to enhance fusion.
Currently all lumbosacral fusion techniques, ALIF, PLIF and TLIF, are typically supplemented by pedicle screw placement. In addition posterior transfacet screws also have been used to supplement ALIF procedures. Complications of pedicle screw placement include duration of procedure, significant tissue dissection and muscle retraction, misplaced screws with neural and/or vascular injury, excessive blood loss, need for transfusions, prolonged recovery, incomplete return to work, excess rigidity leading to adjacent segmental disease requiring further fusions and re-operations. Further advances of pedicle screw fixation including minimally invasive and image-guided technology, and the development of flexible rods have imperfectly addressed some but not all of these issues. Transfacet screws entail the use of long screws which provide a static facet alignment without motion calibration.
Complications of all current interbody fusion devices is their lack of coverage of the majority of the cross sectional area of the vertebral endplates and their potential for extrusion. The recently described flexible fusion system which consists of flexible rods attached to transpedicular screws (Dionysis, Zimmer) suffers from a high pull-out rate, higher rate of re-operation than standard fusions, and does not rank high with patient satisfaction. See for example, Clinical experience with the Dynesys semirigid fixation system for the lumbar spine: Surgical and patient - oriented outcome in 50 cases after an average of 2 years ; D, Grob, A. Benini and A. F. Mannion. Spine Volume 30, number 3, Feb. 1, 2005.
Single or multiple level anterior cervical spinal fusions typically employ the replacement of the cervical disc or discs with autologous or allograft bone, or an intervertebral spacer filled with autologous or allograft bone, demineralized bone matrix, BMP or rh-BMP etc. Currently these anterior cervical fusions are augmented with anterior vertical titanium plates which cross the intervertebral space or spaces and are secured to the vertebral bodies above and below the disc space or spaces with perpendicularly penetrating vertebral body screws. The purpose of these plates is to serve as a barrier to prevent extrusion of the intervertebral disc replacement. Recently anterior vertical plating has also been employed in anterior lumbar fusion.
Complications of anterior spinal plating include the potential for neurovascular injury with screw misplacement, screw and/or plate pull-out, and screw and/or plate breakage. Other complications include potential esophageal compression/injury in the cervical spine secondary to high plate profile or pull-out, and to potential devastating vascular injury in the lumbar spine with plate movement and/or dislodgement into anterior iliac vasculature. Recent advances in cervical plating have therefore concentrated on the creation of lower profile plates and even resorbable plates. These advances, however, have not eliminated the possibility of plate dislodgement and screw back out/breakage.
To achieve segmental fusion applicants propose the use of novel bi-directional fixating transvertebral (BDFT) screws which can be strategically inserted via anterior or posterior surgical spinal approaches into the anterior and middle columns of the intervertebral disc space. The BDFT mechanism employs turning one or two pinions which then turns one or two central gears which in turn simultaneously controls expansile movement of right and-left-handed bi-directional screws. The vertebral bodies above and below the disc space by virtue of their engagement and penetration by the BDFT screws are thus linked and eventually fused. The casings of the BDFT screws prevent vertebral body subsidence. The inside of the denuded intervertebral space can then be packed with autologous or allograft bone, BMP, DBX or similar osteoinductive material. Alternatively an intervertebral spacer filled with either of these substances can be inserted.
Applicants postulate that BDFT screws provide as strong or stronger segmental fusion as pedicle screws without the complications arising from pedicle screw placement which include screw misplacement with potential nerve and/or vascular injury, violation of some healthy facets, possible pedicle destruction and blood loss. By placing screws across the intervertebral space from vertebral body to vertebral body engaging anterior and middle spinal columns, and not into the vertebral bodies via the transpedicular route, some of the healthy facet joints are preserved. Because this technique accomplishes both anterior and middle column fusion, without rigidly fixing the posterior column, it in essence creates a flexible fusion. This device therefore is a flexible fusion device because the preserved posterior joints retain their function achieving at least a modicum of mobility and hence a less rigid (flexible) fusion.
The very advantage of trans-pedicular screws which facilitate a strong solid fusion by rigidly engaging all three spinal columns (anterior, middle and posterior), is the same mechanical mechanism whereby complete inflexibility of all columns is incurred thereby leading to increasing rostral and caudal segmental stress which leads to an increased rate of re-operation.
Transvertebral fusion also leads to far less muscle retraction, blood loss, and significant reduction in O.R. time. Thus the complication of pedicular screw pull-out and hence high re-operation rate associated with the current embodiment of flexible fusion pedicle screws/rods is obviated. The lumbosacral BDFT screws can be introduced via PLIF, TLIF or ALIF operative techniques. Although one can opt to supplement these screws with transpedicular screws there would be no absolute need for supplemental pedicle screw fixation with these operative techniques.
Bi-directional fixating transvertebral (BDFT) screws can also be combined with novel zero-profile horizontal cervical and lumbar mini-plates. They can also be combined with mini-plates and a cage with slots for bone material insertion. Thus this is in essence a three-in-one device; 1) cage which can be filled with bone, 2) a plate and 3) BDFT screws.
For the performance of anterior cervical, and lumbar anterior or posterior fusions one or two centrally placed BDFT screws anterior to an interverterbal graft or spacer, may be a sufficient barrier by itself to prevent device/graft extrusion. However, to further safeguard against graft/spacer extrusion applicants have devised horizontal linear mini-plates which can be incorporated into two anteriorly placed BDFT screws, as well as a linear triangulating mini-plate which can be incorporated into two anteriorly placed, and one posteriorly placed BDFT screws. The horizontal linear mini-plates or horizontal triangular mini-plate traverse the diameter of the disc space and most of the disc space height. Thus a horizontal mini-plate placed anteriorly immediately beneath the rostral and caudal ventral vertebral body surfaces which is secured by BDFT screws which are also beneath the vertebral body surfaces, would prevent intervertebral device/graft extrusion. This mini-plate is essentially a zero- to sub-zero-profile plate in that it is either flush with the vertebral body surfaces or below them.
Because the BDFT screws engage a small percentage of the rostral and caudal vertebral bodies, this plating system could be performed at multiple levels. This plating system which utilizes BDFT screws does not lead to any esophageal compression or injury in the cervical spine or vascular iliac vein injury in the lumbar spine. For the performance of two or three level intervertebral fusion with horizontal mini-plates there is virtually no possibility of plate breakage which can occur in long vertical anterior plates which are in current usage. Similarly, screw dislodgement, if it occurs would lead to minimal esophageal compression or injury compared to large vertical plate/screw dislodgement. In addition, in the cervical spine BDFT screw placement closer to the midline would avert any possibility of lateral neural or vertebral artery injury.
In copending PCT Patent Application PCT/US2005/016493, filed May 11, 2005, the entire contents of which are incorporated by reference, applicants developed an interbody expansile artificial disc device composed of an inner core artificial disc surrounded by expansile titanium shells with spikes which can expand in two or three dimensions. In yet another embodiment of tranvertebral fixation applicants propose a novel cervical and thoracic/lumbosacral intervertebral fusion device (IBFD) which combines the expansile titanium or PEEK shells or our previous artificial disc design with BDFT screws which can be inserted into the disc space.
Yet another embodiment incorporates a core expansile elastometric porous balloon sheath vulcanized to the expandable external shells which can then be filled with bone fusion material. Balloon porosity would allow fusion to occur from vertebral endplate to endplate. Bony material can be injected into this porous balloon through a port directly or through a silastic catheter (see previous patent).
If one were inclined to further enhance posterior column thoraco-lumbosacral fixation, applicants introduce an optional novel calibrated facet stapling device which staples the inferior articulating facet of the superior segment to the superior articulating facet of the caudal vertebral segment unilaterally or bilaterally, further minimizing motion until interbody fusion occurs. The degree of flexibility can be further modulated by varying the calibration strength and torque of facet stapling. This would be dictated by the need for greater or lesser degrees of motion preservation.
Currently, failed anterior lumbar arthoplasties are salvaged by combined anterior and posterior fusions. BDFT screws and/or IBFDs could be utilized as a one-step salvage operation for failed/extruded anteriorly placed lumbar artificial discs obviating the above salvage procedures which have greater morbidity. Likewise, for anterior cervical fusion, applying cervical BDFT screws alone or in combination with cervical mini-plates addresses the deficiencies and complications of current cervical plating technology as mentioned above.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-D illustrate three-dimensional and cross-sectional views of the BDFT screw and its mechanism of operation (Embodiment I).
FIGS. 2A-G illustrate three-dimensional and cross-sectional views of the BDFT screw and its mechanism of operation (Embodiment II).
FIGS. 3A-E illustrate three dimensional, cross-sectional and exploded views of the BDFT screw and its mechanism of operation (Embodiment III).
FIGS. 4A-C illustrate a single or three BDFT screws inserted into adjacent vertebral bodies.
FIGS. 5A and 5B illustrate three-dimensional views of the zero-profile linear mini-plate.
FIGS. 5C and 5D illustrate the integration of BDFT screws in the zero-profile linear mini-plate.
FIGS. 6A through 6G illustrate different views of the zero-profile triangular mini-plate, its integration with BDFT screws and incorporation into the vertebral bodies.
FIGS. 6H and 6I illustrate different views of the three-in-one device combining a zero-profile horizontal mini-plate, a cage with incorporated slots for the placement of bone material, and BDFT screws
FIGS. 7 A and 7 B illustrate the lumbar two-dimensionally expanding intervertebral fusion device (IBFD) with incorporated BDFT screws.
FIGS. 8A-N illustrate the facet joint calibrated stapling device which staples the inferior articulating facet with the superior articulating facet. Increasing degrees of torque calibration leads to increasing posterior column rigidity, whereas decreasing degrees of calibration leads to increasing flexibility.
FIGS. 8O and 8P illustrate four frontal and perspective views of the facet staple with sequential increasing calibrated positions leading to decreasing increments of joint motion/flexibility.
FIGS. 8Q and 8R illustrate the stapled inferior and superior interarticulating facets by the facet stapler.
DETAILED DESCRIPTION OF THE INVENTION
1. The Medical Device
Referring to FIGS. 1A-D the above described problem can be solved in the cervical, thoracic and lumbar spine by insertion into the denuded intervertebral disc space an expansile bi-directional fixating transvertebral (BDFT) screw 100 or screws.
FIGS. 1A and 1B illustrate three-dimensional views of the screw 100 in closed and opened positions, respectively, upon its insertion into the intervertebral disc space. The screw 100 is self-drilling. The mechanism of its action entails the turning of a midline drive screw 100 /pinion 104 in a clock-wise direction. This motion is bi-directionally translated via an interposing gear mechanism 105 enabling the simultaneous outward movement of left and right handed screws 102 , 103 in equal and opposite directions. When the drive screw 101 and its accompanying drive screw shaft are turned clock-wise, the driving pinion 104 is likewise rotated. This motion is then translated to the driven gear 105 which is interposed between the drive screw 101 and two opposing self-drilling screws 102 , 103 , one left-handed and the other right-handed. The gear ring 110 has screw coupling slots ( FIGS. 1C and 1D ). There are also symmetric keyways 120 and an alignment cylinder 113 . The left handed screw 102 fits into one half of the slots 114 , 115 and the right handed screw 103 into the other half of the slots. This is clearly illustrated in cross sections of the screw and gear in FIGS. 1C and 1D , respectively.
FIGS. 1A-C also illustrate the external casing 111 of the device which contains the external screw threads 117 , 118 , against which the left and right handed internal threads interact 116 , 119 with. The casing includes an upper left casing 111 b and an upper right casing 111 a . Below the upper casing 111 b there is a surface serration pattern 118 which is part of a retaining outer shell 112 .
FIGS. 2A-G illustrate Embodiment II of the BDFT 200 . This design differs in two fundamental ways from Embodiment I. Firstly the driving pinion 201 accomplishes bi-directional movement by engaging left and right gears 204 , 205 which simultaneously turn left and right screws 202 , 203 ( FIGS. 2C-G ). Secondly, in it's resting closed position the solid left screw 202 with a narrower diameter is buried within the right wider diameter hollow right screw 203 . This mechanism allows for greater length of screw expansion compared to Embodiment I. Maintaining alignment of screws 202 , 203 and pinions 201 is accomplished by upper casings 211 , outer shells 212 , and left and right screw caps 209 a , 209 b ( FIGS. 2A-G ).
FIGS. 3A-E illustrate Embodiment III of the BDFT 300 . This is similar to Embodiment II. The major difference is the use of two separate driving screws pinions 301 a , 301 b for the two separate gears 304 , 305 . There is one pinion 301 a for the left screw 302 and another pinion 301 b for the right screw 303 . The left screw 302 engages the left gear 304 which engages the left screw 302 . The right pinion 301 a engages the right gear 305 which engages the right screw 303 . Because the left and right screws 302 , 303 have separate controls and are not linked by one common pinion, separate distinct motions of the screws 302 , 303 can be obtained, as opposed to equal and simultaneous screw movements of Embodiments I and II. Like Embodiment II, Embodiment III consists of a smaller diameter solid left screw 302 which fits into a larger diameter hollow right screw 303 . This can achieve significant screw extension length as in Embodiment II.
FIGS. 4A and 4B illustrates the placement of a single BTFD 1000 screw anteriorly into the intervertebral space between adjacent lumbar vertebrae 400 . FIG. 4A illustrates the closed position. FIG. 4B illustrates the opened position. The illustrations are of a generic BDFT screw 1000 i.e. it applies to Embodiments I-III. Placement of a single BDFT anterior to an intervertbral spacer may be sufficient to prevent interspacer/device extrusion, and enhance spinal stability.
FIG. 4C illustrates the placement of three BTFD screws 1000 in a triangulating manner covering anterior and middle columns. The presence of three screws so situated would prevent subsidence of the screws 1000 . Hence they act as a very open IBFD 1000 . Bone material in the form of DBX or BMP etc. could be inserted into the intervertebral space in between the three screws 1000 . This construct could be used as a supplemental or stand alone-intervertebral fusion device. Also illustrated is a cross-section of a vertebral endplate 401 demonstrating the triangular placement of screws 1000 engaging anterior and middle columns.
FIG. 5A illustrates the zero-profile horizontal linear mini-plate 500 . Note the slots for placement of the BDFT screws 1000 . On the anterior surface are slots 504 for the driving pinion screws. FIG. 5B illustrates that the plate 500 consists of upper and lower portions 500 a , 500 b which articulate with each other via interdigitation of alignment pins 502 and recesses 503 . FIG. 5C illustrates the integration of the BDFT screws 1000 into the mini-plate 500 . FIG. 5D illustrates the placement of the plate-BDFT construct into the intervertebral space. After the construct is placed into the intervertebral space, the screws 1000 are expanded bi-directionally in order to engage the vertebral bodies 400 . This construct can be surgically placed via anterior or posterior approaches.
FIGS. 6A-G illustrate a zero-profile triangular mini-plate 600 . In this embodiment the plate encompasses all three triangularly situated BDFT screws 1000 . The posteriorly placed BDFT screw 1000 is expanded with a centrally placed drive screw/pinion with a long stem which extends posteriorly.
As illustrated in FIGS. 6H and 6I this embodiment 600 ′ could be made hollow to accommodate the packing of bone material and can actually function as a combined three-in-one fusion cage/plate/BDFT screw construct. Note that this plate embodiment 600 ′ also has upper and lower components similar to 600 a , 600 b ( FIGS. 6A-C ). Preferably, plates 600 ′ a and 600 ′ b , however, include slots 610 for placement of bone material. FIGS. 6D-F illustrate the incorporation of the BDFT screws 1000 into the triangular mini-plate 600 . FIG. 6G illustrates the positioning of the triangular mini-plate 600 with incorporated expanded screws 1000 into adjacent vertebral bodies 400 .
FIGS. 7A and 7B illustrate a boomerang shaped thoracolumbar IBFD 700 with ratchetable titanium or PEEK shells 710 , 711 which can expand geometrically in two dimensions. FIG. 7A illustrates the BDFT screws 701 , 702 , 703 in partially expanded position. FIG. 7B illustrates the BDFT screws 701 , 702 , 703 in fully expanded position. The outer shells 710 , 711 themselves when ratcheted width-wise have titanium or PEEK spikes 713 inserting themselves into and purchasing the endplates 401 , thus securing permanent integration into the vertebral endplates 401 . The outer shell 710 , 711 surfaces can be treated with hydroxyappetite to facilitate bone incorporation. These shells are fully described in our previous PCT Patent Application PCT/US2005/016493, filed May 11, 2005.
The IBFD device 700 has four shells and a plurality of spikes 713 . The height can be modified by adjusting four fixed height screws 712 . Sequential turning of these screws 712 leads to height expansion between the rostral and caudal shells 710 , 711 by widening the distance between their superior and inferior shells 710 a , 710 b . Once the IBFD 700 is properly positioned in the interspace the spikes 713 engage and purchase the vertebral endplates 401 . The three incorporated BDFT screws 701 , 702 , 703 are turned clockwise leading to anterior and middle column engagement of the vertebral bodies 400 above and below the disc space. The BDFT screws 701 , 702 , 703 are strategically placed; one on each side of the superior shell 710 a and one centrally on the inferior shell 710 b . This captures anterior and middle columns of the vertebral column increasing spinal stability. After the BDFT screws 701 , 702 , 703 are successfully purchased within the vertebral bodies 400 , bone fusion substances are placed/packed or poured, into the inner aspects of the device 700 and its surrounding intervertebral space.
An alternative thoracolumbar IBFD embodiment not illustrated expands in two dimensions and has the additional feature of an incorporated expansile porous elastometric sheath molded to the inner aspects of the titanium shells. Within the balloon is a port with or without an attached microsilastic catheter through which bone fusion material can be injected. Supplemental bone fusion material can be added to the surrounding area of the device to further enhance fusion. Furthermore for certain patients where applicable, a rapid fusion can be effected by the instillation of methyl-methacrylate A similar embodiment for a cervical IBFD is based on our previously described two-dimensional cervical expansion device in PCT Patent Application PCT/US2005/016493, filed May 11, 2005.
The engagement of the IBFD shell spikes 713 and the BDFT screws 701 , 702 , 703 into the vertebral bodies 400 above and below the device would obviate the need for any kind of anterior plating system.
FIGS. 8A-N illustrate a calibrated facet joint stapler 800 which can be used to staple the thoracolumbar inferior and superior articulating facets with incremental torquedegrees. Incrementally increasing the degrees of calibration modulates the extent of facet joint flexibility. This can be used as an option to provide posterior column support and can be used in an open, or percutaneous, endoscopic or fluoroscopic approach. Depending on the operative approach and the individual patient, facet stapling can be performed unilaterally or bilaterally.
The stapling device 800 consists of two orthogonally placed levers 801 a , 801 b which open and close over a triangular fulcrum 810 . The edges of the levers 801 a , 801 b are attached to left sand right staple cartridges 802 a , 802 b . Each cartridge 802 a , 802 b holds a titanium staple 803 a , 803 b in its slots. FIG. 8A illustrates an exploded view of the joint stapler 800 and its essential components. FIGS. 8B and 8C illustrate the stapler 800 in open position. FIGS. 8D and 8E illustrate the stapling device 800 and staples 803 a , 803 b in closed position. FIGS. 8F and 8G illustrate the stapling device 800 and 803 a , 803 b staples in closed, staple released, position. FIG. 8H-J illustrate the components of the lever 801 a , 801 b which includes the grip handle 815 , arm 816 , rounded wedge 817 and fulcrum screw hole 818 . FIGS. 8K and 8L illustrate the details of the cartridge 802 a , 802 b including its slot for the fulcrum 810 and staples 803 a , 803 b . FIGS. 8M and 8N illustrate the details of the fulcrum 810 which include right and left cartridge slots 820 a , 820 b and fulcrum screw 812 and mating alignments. Most importantly it has four incremental calibration slots for incremental degrees of facet joint stapling. Also illustrated are spring anchors 814 .
FIGS. 8O and 8P illustrate frontal and perspective views, respectively of the two opposing titanium facet staples 803 a , 803 b . Each staple 803 a , 803 b consists of a bracket 836 , a nail 837 and an alignment pin 835 . Illustrated are four sequential calibrated tightening positions of the opposing staples 803 a , 803 b . Increasing the calibrated opposition of the two staples 803 a , 803 b leads to increasing opposition of the facet joints and hence increasing rigidity, and decreasing flexibility. Each staple 803 a , 803 b has two alignment recesses 838 . The opposition of these staples 803 a , 803 b around the facet joint forms a rectangular facet joint enclosure.
FIGS. 8Q ad 8 R illustrate the stapled inferior and superior articulating facets 851 , 852 . FIG. 8R illustrates the application of the facet stapler 800 on the facets 851 , 852 introducing the facet staple 803 . The facet staple is used to join the exterior articulating facet 851 and the interior articulating facet 852 .
2. The Surgical Method
The surgical steps necessary to practice the present invention will now be described.
The posterior lumbar spine implantation of the BDFT screws 1000 , plate and IBFD can be implanted via a previously described posterior lumbar interbody fusion procedure (PLIF) or posterior transforaminal lumbar interbody fusion procedure (TLIF). The procedure can be performed open, microscopic, closed, tubular or endoscopic. Fluoroscopic guidance can be used with any of these procedures.
After the adequate induction of anesthesia, the patient is placed in the prone position.
A midline incision is made for a PLIF, and one or two parallel paramedian incisions or a midline incision is made for a TLIF. For the PLIF a unilateral or bilateral facet sparing hemi-laminotomy is created to introduce the BDFT screws 1000 , plates or IBFD into the disc space after it is adequately prepared. For the TLIF procedure, after a unilateral dissection and drilling of the inferior articulating surface and the medial superior articulating facet, the far lateral disc space is entered and a circumferential discectomy is performed. The disc space is prepared and the endplates exposed.
There are then multiple embodiments to choose from for an intervertebral body fusion. With the first and simplest choice, under direct or endoscopic guidance one BDFT screw 1000 or three BDFT screws 1000 can be placed in a triangulating manner encompassing the anterior and middle vertebral columns ( FIGS. 4A-C ). The screws 1000 are then maximally expanded purchasing and uniting the vertebral bodies above and below the disc space. Bone material or an alternative intervertebral fusion device can then be packed into the disc space. The casing of the screws 1000 prevents subsidence of the vertebral bodies. An additional option in the posterior lumbar spine is to place a mini-plate dorsally underneath the thecal sac to prevent bone migration into the nerves. In addition via a TLIF approach a triangular mini-plate/cage construct can be inserted, and then the BDFT screws 1000 maximally expanded. This is a very simple and practical supplemental or stand-alone intervertebral fusion device.
Using an alternative IBFD option, utilizing specialized forceps the two-dimensional expanding thoracolumbar expandable IBFD 700 ( FIGS. 7A and 7B ) is introduced into the disc space. The final dimension expansion in all embodiments leads to purchasing of the spikes into the vertebral endplates. The BDFT screws 1000 are then driven directly into rostral and caudal vertebral bodies across the intervertebral space. Then bone fusion material; autologous, allograft, bone matrix protein, BMP, rh-BMP, paste or other similar currently available or specially designed osteoconductive substances can be placed into the device and the surrounding intervertebral space. In embodiments with an incorporated viscoelastic balloon sheath, prior to engaging the screws the expandable elastometric sheath/balloon is filled with bone fusion material as mentioned above. If desirable, further material, can be placed outside its confines within the intervertebral space.
If further posterior column stability or rigidity is required, unilateral or bilateral, single level or multiple level facet screw stapling can be performed under open, microscopic flouroscopic or endoscopic vision. Radiographic confirmation of staple position is obtained. Calibrated stapling leads to opposition of the facet joints with incremental degrees of joint opposition. This can lead to variable degrees of posterior column rigidity and/or flexibility.
The anterior lumbar spine implantation of solitary BDFT screw(s) 1000 , BDFT screws incorporated into a horizontal linear or triangular mini-plate, or the IBFD/BDFT screw embodiment for L4/5 and L5/S1 interspaces can be performed on the supine anesthetized patient via previously described open micropscopic or endoscopic techniques. Once the disc space is exposed and discectomy and space preparation is performed, placement of one, two or three BDFT screws 1000 with or without a ventral mini-plate, or placement of two dimensionally expanding IBFD with or without expansile elastometric sheaths and their incorporation is identical to that performed for the posterior approach.
The posterior placement of the BDFT screws 1000 alone or combined with mini-plates or with IBFD embodiments into the thoracic spine can be performed via previously described transpedicular approaches; open or endoscopic. The anterior placement of the IBFD 700 into the thoracic spine can be accomplished via a trans-thoracic approach. Once disc space exposure is obtained via either approach, all of the above mentioned embodiments can be inserted. Engagement of the devices is identical to what was mentioned above.
For anterior placement of the cervical embodiments of the BDFT screw(s) 1000 with or without the horizontal linear or triangular cervical mini-plate, and the IBFD embodiments the anterior spine is exposed in the anesthetized patient as previously described for anterior cervical discectomies. Once the disc space is identified, discectomy is performed and the disc space prepared. Implantation and engagement of all devices is identical to that described for the anterior lumbar and thoracic spines.
The present invention may provide an effective and safe technique that overcomes the problems associated with current transpedicular-based thoracic and lumbar fusion technology, and with current vertical cervical plating technology, and for many degenerative stable and unstable spine diseases, and could replace many pedicle screw-based and anterior vertical-plate based instrumentation in many but not all degenerative spinal conditions. Calibrated facet joint screw staples can facilitate flexible fusions and could replace current static trans-facet screws.
To our knowledge there has not been any other previously described bi-directional screw for use in the spine, other joints, or for any commercial or carpentry application. The bi-directional screw 1000 described herein may indeed have applications in general commercial, industrial and carpentry industries. To our knowledge the description of zero to subzero profile anterior or posterior horizontal spinal plates which traverse the diameter of the disc space has not been previously described. To our knowledge an intervertebral three-in-one construct combining bone cage, plate and screws has not been previously reported. To our knowledge calibrated facet joint staples 803 a , 803 b have not been previously described. | An apparatus and method for joining members together using a self-drilling screw apparatus or stapling apparatus are disclosed. The screw apparatus includes a shell and first and second first screw members having tapered ends and threaded bodies that are disposed within the shell. A drive mechanism rotatably drives the first and second screw members from the shell in opposite directions and causes the screw members to embed themselves in the members to be joined. The screw apparatus can be used to join members such as bones, portions of the spinal column, vertebral bodies, wood, building materials, metals, masonry, or plastics. The stapling apparatus includes first and second lever arms rotatably joined together at a fulcrum, and the lever arms rotate in opposite directions. First and second cartridges are disposed at the ends of the lever arms. Each cartridge is capable of holding a staple including a bracket, a nail member and an alignment slot. When the ends of the lever arms are rotated towards each other the staples from the cartridges are interlocked. The staples can be also be used to join members such as bones, portions of the spinal column, or vertebral bodies. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority to U.S. Provisional Patent Application No. 60/175,602, filed Jan. 11, 2000, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The subject invention relates to a plate valve for use with reciprocating compressors, and more particularly to, a valve having a sealing plate with contoured sealing surfaces.
2. Background of the Related Art
Reciprocating compressors are positive-displacement machines which generally include a piston, a piston rod, a cylinder, at least one suction valve and at least one discharge valve. In reciprocating compression, a medium, usually gas or air, is compressed by trapping the medium in an enclosed cylinder and then decreasing its volume by the action of a piston moving inside the cylinder. The medium is compressed to a pressure sufficient to overcome the spring tension holding a discharge valve closed, at which time the discharge valve opens and allows the compressed medium to leave the cylinder.
Because of the nature of the reciprocating piston, compression ceases at the limits of its stroke, the discharge valve again closes due to the action of the springs on the valve, the piston reverses direction, and a small amount of medium remaining in the cylinder expands, increasing in volume and decreasing in pressure. When the inlet pressure is higher than the pressure inside the cylinder and the spring tension holding the suction valve closed, the suction valve then opens, allowing the medium to flow into the cylinder. At the opposite limit of the piston stroke, the suction valve closes due to the springs acting on the valve, the piston again reverses direction, and the compression cycle begins anew.
Of the many components in a reciprocating compressor, none work harder nor serve a more important function than the suction and discharge valves. In fact, compressor efficiency is determined by the performance of the valves more than any other component. For optimum compressing efficiency to be achieved, these valves must be configured to provide a maximum flow area while at the same time, the medium flow through the valve must meet with a minimum resistance. In addition, it is critical that valve closure prevent leakage of gas or air in either direction.
Many compressors are run at peak loads for weeks or months at a time with no relief. In a typical 1000 rpm compressor, the valves which operate automatically with every stroke of the piston, open and close almost three million times a day. Therefore, in order to achieve optimum compressor efficiency, valve design must meet the above-mentioned objectives of efficient medium flow and control.
Generally, a compressor valve (discharge or suction) is composed exteriorly by two components, namely a valve seat and a valve guard. The valve seat provides inlet flow ports for the medium. The interior surface of the valve seat defines what is traditionally termed the seating surfaces. The valve guard defines outlet flow ports and is typically secured to the valve seat by bolts or a central stud and is spaced therefrom. Internally, the compressor valve is composed of a sealing plate or a series of rings and biasing elements such as helical springs. The sealing plate is disposed in the space between the valve seat and valve guard and is axially movable therein. The surfaces of the plate or rings which are located adjacent to the valve seat are termed sealing surfaces. These surfaces are designed to be engaged with corresponding seating surfaces of the valve seat. A biasing element is disposed between the valve guard and the sealing plate, urging the sealing plate sealing surfaces into a sealing engagement with the seating surface of the valve seat. In this biased position, the medium is prevented from flowing through the valve. As mentioned previously, when the operation of the compressor is such that sufficient pressure exists to overcome the force applied to the sealing plate by the biasing element, the valve will open allowing medium to flow into or out of the compressor cylinder.
The configuration of the sealing plate sealing surfaces and their engagement with the valve seat can have a dramatic impact on the flow of medium through the valve. In the compressor valves commonly in use today, there is an appreciable velocity head loss occasioned by problems in moving the fluid through the valve at high velocity. The problems are largely caused by energy losses resulting from extreme changes in flow direction, frictional interference and turbulence by the fluid as it passes through the compressor valve, around the sealing surfaces. These problems are especially critical in attempting to obtain optimum efficiency and capacity in high speed compressors undergoing 800 to 4000 strokes of the piston per minute.
In addition, configuration of the sealing plate sealing surfaces and their engagement with the valve seat can significantly impact the ability to prevent leakage of medium in either direction when the valve is in the closed position. Performance of the compressors, which by their nature have a very short stroke, requires valves which not only permit flow of the fluid or gases to and from the cylinder with a minimum of pressure loss and at a high velocity, but which will also seat rapidly and positively during the critical pressure reversals which take place at the beginning and end of the intake and discharge strokes.
Traditionally, a sealing plate for a compressor valve consisted of a circular plate that had opposed planar surfaces with flow ports extending between the opposed surfaces. For these valves the seating surfaces were planar and did not protrude into the flow ports of the valve seat, but merely covered the ports. U.S. Pat. No. 3,123,095 to Kohler discloses a plate valve with a sealing plate having planar seating surfaces. A disadvantage to this configuration, as well as others having planar sealing surfaces, is that flow through the valve tends to be turbulent resulting in increased pressure loss across the valve. The turbulence is caused by the rapid change in the direction of flow through the valve. In compressor valves, the flow ports of the sealing plate and the valve guard are aligned, but for obvious reasons these ports are offset from the inlet ports of the valve seat. As a result, the flow proceeds into the valve through the valve seat and must rapidly change direction in order to traverse to the ports in the sealing plate. This rapid change in direction results in the turbulent flow.
In an effort to improve the flow through the valve, sealing plates were furnished with profiled sealing surfaces which facilitate the flow through the valve by providing a smoother transition from the inlet flow ports of the valve seat to the flow ports of the sealing plate and valve guard. U.S. Pat. Nos. 3,536,094 to Manley discloses a prior art compressor valve having a sealing plate or rings with profiled sealing surfaces. The sealing surfaces in the Manley patent have a convex spherical cross-section which engages in concave spherical seating surfaces in order to interrupt the flow through the valve.
U.S. Pat. Nos. 4,924,906 and 5,052,434 to Harbal and Bauer receptively, also disclose valves with profiled sealing surfaces. Both of these patents disclose sealing surfaces that can be provided in a variety of cross-sections and engage in corresponding recesses in the valve seat. The Hrabal patent uses sealing rings which have a profiled cross-section and a support plate as the means for restricting and directing flow through the valve. The Bauer patent uses two piece rings of various cross-section to facilitate valve flow and closure.
The disclosures in the Manley, Harbal and Bauer patents attempt to provide a compressor valve that minimizes the velocity and pressure loss through the valve and increase the compressor efficiency by profiling the sealing surfaces. A disadvantage to these configurations is that the improvement in flow through the valve is achieved at the expense of valve seating performance. As noted, the optimum performance of the compressor requires valves which not only permit flow of the fluid or gases to and from the cylinder at a high velocity with a minimum amount of pressure loss, but which will also seat rapidly and reliably. The use of profiled sealing surfaces which are designed to mate with a corresponding profiled seating surface results in surface to surface contact (a surface contact condition). Having surfaces that mate reduces the contact pressure associated with the engagement of these surfaces and in turn reduces the reliability of the seal.
More specifically, contact pressure is a function of the contact force applied divided by the area of contact. The higher the contact pressure, the more reliable the seal. In compressor valves, the contact force is a result of the differential pressure across the valve and is primarily equal to the force exerted by the biasing element and has a constant magnitude. As a result, the only way to increase the contact pressure is to reduce the area of contact. It has been shown that a more reliable and rapid valve closure is achieved when the surfaces do not mate and the engagement between the sealing and seating surfaces occurs along a continuous line of contact.
There is a need, therefore, for a new valve which improves the flow of medium through the valve by providing a smoother transition from the inlet flow ports of the valve seat to the flow ports of the sealing plate and valve guard while at the same time improving the reliability of the seat engagement by increasing the engagement contact pressure.
SUMMARY OF THE INVENTION
The subject application is directed to a new and improved valve for use with reciprocating compressors, and more particularly to, a compressor valve having a sealing plate with contoured sealing surfaces, a valve seat, a valve guard and at least one biasing element for urging the sealing plate into engagement with the valve seat.
The valve seat has opposed upper and lower surfaces and defines inlet flow ports. The inlet flow ports extend between the upper and lower surfaces and provide a path for admitting a controlled medium into the valve. The lower surface of the valve seat includes at least one seating surface. The valve guard has a recessed area with opposed upper and lower surfaces and defines outlet flow ports. The outlet flow ports extend between the upper and lower surfaces of the valve guard and provide a path for discharging a controlled medium from the valve. The valve guard is secured to the valve seat and spaced therefrom to enclose the recessed area and define a cavity therebetween.
In accordance with the subject application, the sealing plate has opposed upper and lower surfaces and defines flow ports which extend between the upper and lower surfaces for facilitating flow of a controlled medium through the valve. The sealing plate is positioned within the cavity and moves relative to the lower surface of the valve seat between an open and closed position. In the open position the sealing plate is spaced from the lower surface of the valve seat so as to permit medium flow through the inlet flow ports of the valve seat and in the closed position the sealing plate is engaged with the valve seat so as to prevent medium flow through the valve. The upper surface of the sealing plate defines at least one contoured sealing surface for engaging the at least one contoured seating surface of the valve seat along a continuous line of contact when the valve is in the closed position.
Preferably, at least one biasing element is disposed between the valve guard and the sealing plate, for urging the sealing plate into the closed position. The biasing element is engaged within a corresponding recess in the valve guard. It is envisioned that at least one seating surface of the valve seat includes inclined surfaces oriented relative to the lower surface of the valve seat, wherein the angle of inclination of the inclined surfaces is about between 0 degrees and 90 degrees relative to the lower surface of the valve seat.
Preferably the contoured sealing surface of the sealing plate includes inclined surfaces oriented with respect to the upper surface of the sealing plate, wherein the angle of inclination of the inclined surfaces is about between 55 and about 20 degrees. It is also envisioned the angle of inclination of the inclined surfaces of the valve seat and the angle of inclination of the valve plate can differ from each other by about between 0 degrees and 10 degrees. Preferably, the angle of inclination of the inclined surfaces of the valve seat and the angle of inclination of the valve plate differ from each other by about 3 degrees. In a preferred embodiment of the subject application, the contoured sealing surface of the sealing plate includes curved surfaces for achieving line contact with a valve seat seating surface.
It is envisioned that the sealing plate of the subject invention is formed from a metallic material such as stainless steel, alloy steel, Inconel or titanium. Alternatively, the sealing plate may be formed from an non-metalic material (e.g., a thermoplastic, a thermoset, etc.) or a composite material (either reinforced or non-reinforced), or a material exhibiting substantially similar strength and flexural properties.
The subject invention is also directed to a compressor valve which includes a valve seat, valve guard, at least one biasing element and a sealing plate having first and second contoured sealing rings. The valve seat has opposed upper and lower surfaces and defines arcuate inlet flow ports for admitting a controlled medium. The inlet flow ports extend between the upper and lower surfaces, and the lower surface has first and second, seating surfaces. The valve further includes a valve guard which has a recessed area with opposed upper and lower surfaces. The arcuate outlet flow ports extend between the upper and lower surfaces and provide a path for discharging the medium from the valve. The valve guard is secured to the valve seat and spaced therefrom to enclose the recessed area and define a cavity therebetween.
The sealing plate has opposed upper and lower surfaces and defines arcuate flow ports. The arcuate flow ports extend between the upper and lower surfaces for facilitating flow of medium through the valve. The sealing plate is mounted for movement within the cavity and relative to the lower surface of the valve seat between an open position and closed position. As noted above, the upper surface of the sealing plate defines first and second contoured sealing rings for engaging the first and second seating surfaces of the valve seat along a continuous line of contact when the valve is in the closed position.
The subject invention is also directed to a sealing plate for a compressor valve which includes a valve seat defining inlet flow ports and a valve guard defining outlet flow ports. The sealing plate includes a body having opposed upper and lower surfaces and defines flow ports extending between the upper and lower surfaces for facilitating flow of a controlled medium through the valve. The upper surface of the sealing plate defines at least one contoured sealing surface which engages at least one seating surface of a valve seat when the valve is biased into a closed position thereby, preventing the flow of a controlled medium through the valve. The contoured sealing surfaces have a cross-sectional configuration that is adapted and configured to achieve continuous line contact with the valve seat seating surfaces when the valve is in the closed position.
Those skilled in the art will readily appreciate that the subject invention improves the flow of medium through the valve by providing a smoother transition from the inlet flow ports of the valve seat to the flow ports of the sealing plate and valve guard and improves the reliability of the seat engagement by increasing the engagement contact pressure.
These and other unique features of the valve disclosed herein will become more readily apparent from the following description, the accompanying drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
So that those having ordinary skill in the art to which the present application appertains will more readily understand how to make and use the same, reference may be had to the drawings wherein:
FIG. 1 is a partially exploded perspective view of a prior art plate valve which includes a valve seat, a valve guard, a sealing plate and helical springs, the sealing plate having planar upper and lower surfaces;
FIG. 2 is a partially exploded perspective view of a plate valve which includes a valve seat, a valve guard, a sealing plate, an elongated stud which provides a central axis for the valve, and helical springs;
FIG. 3 is a perspective view of a sealing plate having arcuate flow ports and contoured sealing surfaces which include inclined surfaces with respect to the upper surface of the sealing plate;
FIG. 4 is a top plan view of the sealing plate shown in FIG. 3 in which four arcuate flow ports and four radial webs separate concentric contoured sealing surfaces;
FIG. 5 is a cross-sectional view taken along line 5 — 5 of FIG. 4 in which the sealing surfaces of the sealing plate are contoured having obtuse triangular cross-section;
FIG. 6 is a cross-sectional view of a valve having a sealing plate with contoured sealing surfaces, the sealing plate being operatively positioned between a valve guard and a valve seat which has a substantially planar lower surface, the sealing plate being biased to a closed position by helical springs and thereby engaged with the planar seating surface of the valve seat;
FIG. 6A is an enlarged cross-sectional view of a sealing plate having a contoured sealing surface in continuous linear contact with a valve seat, the valve seat having a seating surface which is substantially planar;
FIG. 7 is a cross-sectional view of a valve having a sealing plate with contoured sealing surfaces, the sealing plate being operatively positioned between a valve guard and valve seat which has a contoured lower surface seating surface, the sealing plate being biased to a closed position by helical springs and thereby engaged with the contoured seating surface of the valve seat
FIG. 7A is an enlarged cross-sectional view of the contoured sealing plate sealing surface engaged with a contoured seating surface of the valve seat, wherein the angle of inclination of the inclined surfaces of the valve seat and the sealing plate differ from each other creating continuous line contact at the point of engagement, the inclination ∝ 1 of the valve seat seating surfaces being greater than the inclination β 1 of the sealing plate inclined surfaces;
FIG. 8 is an enlarged cross-sectional view of a contoured sealing plate sealing surface engaged with the seating surface of a valve seat, wherein the angle of inclination of the inclined surfaces of the valve seat and the sealing plate, ∝ 2 and β 2 , respectively, differ from each other creating continuous line contact at the point of engagement, the inclination ∝ 2 of the valve seat seating surfaces being less than the inclination β 2 of the sealing plate inclined surfaces;
FIG. 9 is a top plan view of a sealing plate in which four arcuate flow ports and four radial webs separate first and second concentric sealing surfaces;
FIG. 10 is a cross-sectional view taken along line 10 — 10 of FIG. 9 illustrating contoured sealing surfaces which have an equilateral triangular cross-section;
FIG. 11 is a top plan view of a sealing plate in which four arcuate flow ports and four radial webs separate concentric sealing surfaces, the sealing plate further including a hole for insertion of an alignment pin which maintains the sealing plate in the desired orientation with respect to the valve seat and valve guard; and
FIG. 12 is a cross-sectional view of the sealing plate taken along line 12 — 12 of FIG. 11 in which the contoured sealing surfaces have an curved convex cross-section.
FIG. 13 is a top plan view of a sealing plate in which four arcuate flow ports and four radial webs separate concentric sealing surfaces, the sealing plate further including a central aperture which facilitates centering of the sealing plate within the valve;
FIG. 14 is a cross-sectional view taken along line 14 — 14 of FIG. 13 illustrating contoured sealing surfaces which have convex cross-section;
FIG. 15 is a top plan view of a sealing plate in which four arcuate flow ports and four radial webs separate concentric sealing surfaces, the sealing plate further including a hole for insertion of an alignment pin which maintains the sealing plate in the desired orientation with respect to the valve seat and valve guard;
FIG. 16 is a cross-sectional view taken along line 16 — 16 of FIG. 15 illustrating a sealing plate with contoured sealing surfaces which have a truncated triangular cross-section;
FIG. 17 is a top plan view of a sealing plate in which four arcuate flow ports and four radial webs separate concentric sealing surfaces;
FIG. 18 is a cross-sectional view of the sealing plate shown in FIG. 17, taken along line 18 — 18 , in which the cross-sections of the contoured sealing surfaces are truncated triangles or trapezoids and the lower surface is similarly contoured;
FIG. 19 is a top plan view of a sealing plate in which four arcuate flow ports and four radial webs separate concentric sealing surfaces; and
FIG. 20 is a cross-sectional view of the sealing plate shown in FIG. 19, taken along line 20 — 20 . in which the sealing surfaces and the lower surface of the sealing plate are similarly contoured.
These and other features of the subject invention will become more readily apparent to those having ordinary skill in the art form the following detailed description of the preferred embodiments.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention overcomes several of the problems associated with prior art plate valves used in reciprocating compressors. The advantages, and other features of the valve disclosed herein, will become more readily apparent to those having ordinary skill in the art from the following detailed description of certain preferred embodiments taken in conjunction with the drawings which set forth representative embodiments of the present invention.
Referring now to the drawings wherein like reference numerals identify similar structural elements of the subject invention, there is illustrated in FIG. 1 a prior art plate valve for use in reciprocating compressors designated generally by reference numeral 10 . Plate valve 10 primarily includes a valve seat 12 having a circular configuration, a valve guard 14 having a circular condition, planar sealing plate 16 and helical biasing elements 18 a - 18 d . Valve seat 12 and valve guard 14 each define a plurality of arcuate inlet and outlet flow ports, designated as reference numerals 22 and 24 , respectively. In the assembled configuration, stud body 40 and nut 50 secure valve seat 12 to valve guard 14 , wherein sealing plate 16 is disposed in a cavity defined between valve seat 12 and valve guard 14 , and is axially movable therein.
In operation, biasing elements 18 a - 18 d , preferably defined by a plurality of helical springs, urge the upper surface 26 of sealing plate 16 against valve seat 12 . In such a position, sealing plate 16 prevents a medium from flowing through the valve 10 by blocking or covering inlet flow ports 22 . As shown in FIG. 1, the upper surface 26 of the prior art sealing plate 16 is planar and does not project into flow ports 22 of the valve seat 12 .
When the pressure on the exterior valve 10 due to the operation of the compressor is sufficient to overcome the force exerted by biasing elements 18 a - 18 d , sealing plate 16 moves axially within the cavity between the valve seat 12 and valve guard 14 until sealing plate 16 contacts valve guard 14 . At such a time the flow of medium proceeds through inlet ports 22 , then through flow ports 30 disposed in sealing plate 16 , and then through outlet flow ports 24 in valve guard 14 . The flow ports in the sealing plate and valve guard, 30 and 24 respectively are aligned, but they are offset from the inlet flow ports 22 in valve seat 12 . Since inlet flow ports 22 are offset from aligned flow ports 30 and 24 , the flow of the medium through valve 10 is not linear and the transition from valve seat 12 to sealing plate 16 requires a change in flow direction. This causes turbulence which results in a pressure drop across the valve 10 . This configuration is similar to the valve assembly shown in U.S. Pat. No. 4,852,608 to Bennitt.
Referring to FIG. 2, there is illustrated a valve constructed in accordance with a preferred embodiment of the subject invention and designated generally by reference numeral 100 . Valve 100 primarily includes a valve seat 110 having a circular configuration, a valve guard 120 having a circular configuration, and a contoured sealing plate 130 . A central axis extends through the center of valve 100 . Valve seat 110 and valve guard 120 define arcuate inlet and outlet flow ports, designated by reference numerals 116 and 126 respectively. Although the flow ports are shown as being arcuate, it is envisioned and within the scope of the subject disclosure that the ports can be linear, rectangular or any shape suitable to facilitate the flow of medium through a valve.
In the assembled condition, stud body 150 and nut 160 secure valve seat 110 to valve guard 120 along the central axis of the valve. Sealing plate 130 is disposed in cavity 128 defined between valve seat 110 and valve guard 120 and is axially movable therein between the open and closed positions. In the closed position, the sealing plate 130 is engaged with valve seat 110 to prevent the flow of medium through valve 100 . In the open position, the sealing plate 130 is spaced from valve seat 110 and medium can flow through the valve 100 . As noted, it is preferable that stud body 40 extends through the central axis of valve 100 . However, those skilled in the art will recognize that other valve configurations exist in which a central stud is not used for securing the valve seat to the valve guard and that this feature is not a limitation to the disclosure provided in the present application.
Referring to FIGS. 3 through 5, sealing plate 130 includes radially inner and radially outer concentric rings 137 a and 137 b connected to one another by circumferentially spaced apart web portions, 136 a - 136 d . It is envisioned that additional ring portions may be provided depending on the intended use and specific environment of the valve. The sealing plate 130 has upper and lower surfaces 138 and 139 , respectively, and defines four flow ports 132 a - 132 d which extend between upper and lower surfaces 138 and 139 . As shown in FIG. 4, flow ports 132 a - 132 d are arcuate and extend for an arc angle of about 70 degrees. However, as noted above, it is envisioned and within the scope of the subject disclosure that the ports can be linear, circular, rectangular or any shape suitable to facilitate the flow of medium through a valve. Also, the quantity of flow ports can vary depending upon the size and configuration of the valve. Of course, if the quantity, size or shape of the flow ports in the sealing plate change, the quantity size and shape of the inlet and outlet flow ports associated with valve seat and valve guard must be adjusted accordingly. Sealing plate 130 also includes a central aperture 142 for facilitating central alignment of sealing plate 130 and an alignment hole 144 , though which alignment pin 172 (see FIG. 2) is engaged to ensure proper rotational orientation of sealing plate 130 with respect to valve seat 110 and valve guard 120 .
Preferably, sealing plate 130 is formed from metals such as an alloy steel or stainless steel. Alloy steels can typically be used in general service applications and stainless steels or special alloys can be used in more corrosive applications. Alternatively, sealing plate 130 can be formed from a non-metallic material or composite material such as Asbestos-Bakelite, Glass-Melamine or a fiber reinforced polymer or thermoplastic. These types of materials are lightweight thereby reducing inertial forces and minimizing the forces exerted on the valve seat. They are also able to resist a wide range of corrosive chemicals.
With continuing reference to FIGS. 3 through 5, the upper surface 138 of sealing plate 130 includes first and second contoured sealing surfaces designated as reference numerals 134 a and 134 b . In this configuration, first and second contoured sealing surfaces 134 a and 134 b include inclined planes 135 a - 135 d which form triangular cross-sections taken along line 5 - 5 of FIG. 4 . The angle of inclination “β” of inclined planes 135 a - 135 d with respect to upper surface 138 is about 30 degrees. In alternate embodiments, the angle β can be in the range of between about 55 and about 20 degrees with respect to the upper surface 138 of sealing plate 130 .
Referring now to FIGS. 6 and 6A, sealing plate 130 is disposed in the cavity 128 defined between valve seat 110 and valve guard 120 and is biased into the closed position by four biasing elements 140 a - 140 d (see FIG. 2 ). As noted previously, seat plate 130 has first and second contoured sealing surface 134 a and 134 b that have a triangular configuration when viewed in cross-section. Alternate embodiments can have one or more sealing surfaces, the quantity being determined by the number of inlet flow ports and being limited by the size of the valve and the desired flow area.
Similar to prior art valves, in operation, biasing elements 140 a - 140 d , which include a plurality of helical springs, but can be a flexible plate member or other biasing means, are disposed between the valve guard 120 and the contoured sealing plate 130 . The biasing elements 140 a - 140 d urge the contoured sealing surfaces 134 a and 134 b of sealing plate 130 into sealing engagement with the seating surfaces 118 a and 118 b of valve seat 110 . When in sealing engagement, sealing surfaces 134 a and 134 b protrude into flow ports 116 and the flow of medium through valve 100 is prevented. When the pressure on the valve seat 110 side of valve 100 is sufficient to over come the force imparted on sealing plate 130 by the biasing elements 140 a - 140 d , valve 100 opens, and medium flows into ports 116 in valve seat 110 . The medium then flows passed the contoured sealing surfaces 134 a and 134 b and into ports 132 a - 132 d (See FIG. 4 ). The contoured sealing surfaces 134 a and 134 b of sealing plate 130 provide a smooth transition for the flow of medium from the valve seat 110 to the sealing plate 130 flow ports 116 . This is a marked improvement over prior art plate valves which have a planar sealing plate
FIG. 6A illustrates an enlarged view of the area designated by localized view “A” in FIG. 6 of a valve having a valve seat 110 with planar seating surfaces 118 a and 118 b . As shown, contoured sealing plate 130 is engaged with valve seat 110 and it has a contoured sealing surface 134 b which includes inclined surfaces 135 c and 135 d . Inclined surfaces 135 c and 135 d are inclined with respect to the upper surface 138 of sealing plate 130 . As a result of this inclination angle β, the engagement of sealing plate 130 with valve seat 110 occurs along a continuous line of contact when the valve is in a closed position. In doing so, the engagement contact pressure is increased, improving the reliability of valve closure. Preferably, surfaces 135 c and 135 d are inclined at about 30 degrees from upper surface 138 . However, the angle of inclination β can be between 55 degrees and 20 degrees relative to the upper surface 138 of the sealing plate 130 .
Referring now to FIG. 7 there is illustrated a compressor valve designated generally by reference numeral 200 . Localized view “A” illustrates the area of valve 200 wherein the contoured sealing surface 234 b of sealing plate 230 sealingly engages valve seat 210 so as to achieve continuous line contact therebetween. This prevents the flow of medium through inlet flow ports 216 . Unlike valve 100 , valve seat 210 has contoured sealing surfaces 218 a and 218 b which serve to facilitate the flow through the valve 200 by providing a smoother transition from the inlet flow ports 116 of the valve seat 110 to flow ports 132 a - 132 d of the sealing plate 130 and valve guard 120 .
Referring to FIG. 7A, sealing plate 230 engages valve seat 210 . Sealing plate 230 has a contoured sealing surface 234 b which includes inclined surfaces 235 c and 235 d . Surfaces 235 c and 235 d are inclined with respect to upper surface 238 at an angle of inclination of β 1 degrees. Seating surface 218 b is inclined with respect to the lower surface 212 of valve seat 210 at an angle of inclination of 1 . In this embodiment, the angle of inclination of the inclined surfaces of the valve seat 210 and the sealing plate 230 , 1 and β 1 respectively, differ from each other whereby the inclination β 1 is less than the inclination 1 . Consequently, the engagement of sealing plate 230 with valve seat 210 occurs along a continuous line of contact when the valve 200 is in a closed position, thereby increasing the engagement contact pressure and improving the reliability of valve closure.
Referring to FIG. 8, sealing plate 330 is engaged with valve seat 310 . Sealing plate 330 has a multi-ring body with contoured sealing surface 334 b which includes inclined planes 335 c and 335 d . Surface 335 c and 335 d are inclined with respect to upper surface 338 of sealing plate 330 by β 2 degrees. The angle of inclination of seating surface 318 b with respect to the lower surface 312 of the valve seat 310 is 2 degrees. In this embodiment, the angle of inclination of the inclined surfaces, 2 and β 2 , differ from each other, such that the inclination β 2 of the sealing plate 330 inclined surfaces 335 c and 335 d is greater than the inclination 2 of the valve seat seating surface 318 b . As a result of the difference in 2 and β 2 , the engagement of sealing plate 330 with valve seat 310 occurs along a continuous line of contact when the valve 300 is in a closed position, again resulting in increased contact pressure and a more reliable valve closure.
Referring now to FIGS. 9 and 10, which illustrate a sealing plate 430 that is substantially similar in structure and function to the sealing plate 130 shown in FIGS. 3 through 5, except that the contoured sealing surfaces 434 a and 434 b thereof have an equilateral triangular cross-sections when viewed along line 10 - 10 of FIG. 9 . As a result of the inclination β of sealing surfaces 434 a and 434 b , the engagement of sealing plate 430 with a valve seat having a planar seating surface or seating surface that is inclined at an angle which is notably different than β, will occur over a continuous line of contact.
Referring to FIGS. 11 and 12 , sealing plate 530 has contoured sealing surfaces 534 a and 534 b that have a curved convex cross-section when viewed along line 12 — 12 of FIG. 11 . As a result of the curvature of sealing surfaces 534 a and 534 b , the engagement of sealing plate 530 with a valve seat having a planar seating surface or seating surface that has inclined planes, will occur over a continuous line of contact. It should be appreciated that the line of contact occurs along a tangent to the curve which forms the contoured sealing surfaces 534 a and 534 b.
Referring to FIGS. 13 and 14, there is illustrated a sealing plate 630 which is substantially similar in structure and function to sealing plate 530 , except that the contoured sealing surfaces 634 a and 634 b have a curved convex cross-section when viewed along line 14 — 14 of FIG. 13 which is much smaller in height than surfaces 544 a and 534 b of sealing plate 530 . As a result of the curvature of sealing surfaces 634 a and 634 b , the engagement of sealing plate 630 with a valve seat having a planar seating surface or seating surface that includes inclined planes, occurs over a continuous line of contact. In particular, the line of contact occurs along a tangent to the curve which forms the contoured sealing surfaces 634 a and 634 b thereby improving the reliability of the valve closure by increasing the engagement contact pressure.
Referring to FIGS. 15 and 16, sealing plate 730 has contoured sealing surfaces 734 a and 734 b that have a truncated triangular cross-section when viewed along line 16 — 16 of FIG. 15 . As a result of the inclination β of inclined surfaces 735 a — 735 d of sealing surfaces 734 a and 734 b , the engagement of sealing plate 730 with a valve seat having a planar seating surface or seating surface that is inclined at an angle which is notably different than β, occurs over a continuous line of contact.
Referring to FIGS. 17 and 18, sealing plate 830 is substantially similar in structure and function to sealing plate 730 , except that the lower surface 839 of sealing plate 830 is contoured in a similar manner to sealing surfaces 834 a and 834 b . The contour of lower surface 839 further facilitates the flow of medium through the valve by assisting in the transition of the flow from flow ports 832 a — 832 d to the valve guard.
Referring now to FIGS. 19 and 20, there is illustrated sealing plate 930 which is substantially similar in structure and function to sealing plate 630 , except that lower surface 939 is also contoured in a manner similar to sealing surfaces 934 a and 934 b . As a result of the curvature of sealing surfaces 934 a and 934 b , the engagement of sealing plate 930 with a valve seat having a planar seating surface or seating surface that consists of inclined planes, will occur over a continuous line of contact and improve the reliability of the valve closure. It should be appreciated that line of contact occurs along a tangent to the curve which forms the contoured sealing surfaces 934 a and 934 b . Additionally, as mentioned previously, having a contoured lower surface 939 further facilitates the flow of medium through the valve by assisting in the transition of the flow from flow ports 932 a - 932 d to the valve guard.
While the invention has been described with respect to preferred embodiments, those skilled in the art will readily appreciate that various changes and/or modifications can be made to the invention without departing from the spirit or scope of the invention as defined by the appended claims. | The subject application is directed to a compressor valve having a valve seat, a valve guard and a sealing plate with contoured sealing surfaces, the valve seat having defining inlet flow ports for admitting a controlled medium into the valve, the lower surface of the valve seat including at least one seating surface, the a valve guard having a recessed area and defining outlet flow ports for discharging a controlled medium from the valve, the sealing plate being positioned within a cavity between the valve guard and valve seat and moves relative to the lower surface of the valve seat between an open and closed position, the upper surface of the sealing plate defining at least one contoured sealing surface for engaging at least one seating surface of the valve seat along a continuous line of contact when the valve is in the closed position. | 8 |
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates in general to sewing machines and in particular to a new and useful sewing machine with a step motor operated feed device which utilizes a feed wheel disposed next to a stitch formation point and which is driven synchronously with stitch formation tools, the feed wheel being driven by a step motor.
In a known sewing machine of this kind (U.S. Pat. No. 2,275,716), the drive of the feed wheel occurs from the main shaft of the sewing machine via a stepping mechanism which imparts an intermittent feed movement to the feed wheel. For continuously variable adjustment, such a stepping mechanism must be designed as a clamping mechanism with a free-wheeling coupling. Due to their frictional entrainment, such stepping mechanisms are very inaccurate, and besides, they cannot be used for driving in a reverse direction. Especially at varying speeds of a sewing machine, because of the large inertial mass of the mechanical transmission parts, there results a considerable slip in the drive transmission and hence considerable deviation of the executed stitch length from the set value. Backward sewing is not possible at all with this sewing machine.
SUMMARY OF THE INVENTION
It is the object of the present invention to provide a drive for the feed device in such a way that small amounts in the forward direction as well as in the opposite direction, can be executed.
Accordingly an object of the present invention is to provide a sewing machine with a feed device which comprises a feed wheel disposed next to a stitch formation point and driven in synchronism with stitch formation means, the feed wheel being mounted and the support provided at the housing of the sewing machine, the feed wheel being operatively connected to a step motor for rotating the feed wheel and to which is supplied stepping pulses over a power stage which are formed by a pulse generator operating in synchronism with a main shaft of the sewing machine, and with a counting device which determines the feed amount and which is presettable by selected digital data contained in a memory.
The term "feed wheel" is understood here to mean either a sliding wheel arranged below the work or a roll foot arranged above it or both. This results in an arrangement which transports work most exactly in both feed directions and which is outstanding for its low inertia without any slip whatsoever. Switching from forward to backward stitching for making a bar is possible at highest speed, with the same stitch length being preserved.
A further object of the invention is to provide a sewing machine as defined above, wherein a deflecting or miter gear and a transmission shaft is mounted in the support, the deflecting or miter gear comprising a ring gear attached to the feed wheel and a pinion firmly connected to the transmission shaft, the step motor being secured to the support and having an output shaft which is rigidly coupled to the transmission shaft.
By this measure, an especially short transmission path is obtained in an arrangement wherein the feed wheel is connected to its drive via a deflection gearing and a transmission shaft mounted in the support, the deflection gearing consisting of a ring gear attached to the feed wheel and of a pinion firmly connected to the transmission shaft, with all the advantages thereof. Especially for the drive of the roll foot, which must be mounted moveable in its height position and whose support must also be mounted for outward pivoting for the threading of the needle, such a compact arrangement is practically mandatory if a clumsy complicated drive is to be avoided.
An especially favorable solution for use of a relatively small step motor usable in a limited space, results from the use of a spiroid gearing as the deflecting gearing. A spiroid gearing is a helical gearing with crossed but not intersecting axes. In a spiroid gearing a plurality of teeth is in engagement simultaneously. In addition, the contact line of the sliding movement is practically perpendicular to the direction of force. The arc radius of the contact lines is substantially greater than in a worm gear of comparable size. This results in a fully sliding motion along the entire surface of the tooth sides of the ring gear and also in a uniform running without irregularities and an extradordinary firmness of the gearing. Above all, the gears can be made to run without play. Thus the spiroid gearing has a high force transmission capacity and by the selection of appropriate pitch angles, very high transmission ratios can be obtained. Due to the small distance between the centers of the ring gear and pinion, the design is extremely compact. Moreover, the spiroid gearing is self-locking, so that there is no need for a brake to prevent forward or reverse running and there are no reactions through the workpiece to the feed wheel. But on the other hand, drive in both feed directions is possible. It is gearing which runs quietly, is easy and inexpensive to manufacture, and can operate with a small servometer.
Another object of the invention is to provide the sewing machine with a support which is mounted on an eccentric bolt rotatably secured to the housing of the sewing machine. The support is thus moveable in a vertical direction and can be fixed in a selected position by a clamping connection arranged at a location space from the eccentric bolt.
This results in an especially simple adjustability both with regard to the height of the sliding wheel part protruding from the stitch plate as well as the lateral position of the sliding wheel inside the stitch plate slot.
Another feature of the invention is to provide the support for the feed wheel as two parts, one of which receives the transmission shaft and step motor and which is secured for axial displacement to the other part which is formed as a tubular piece. This offers an especially simple solution for play-free setting of the gear connection.
Other features of the invention include the use of circuitry for interpreting pulses from the pulse generator, the circuitry including a reversing arrangement and counting devices which are connected to an oscillator for delivering constant pulses. The circuitry includes a turnoff device which stops the stitch formation mechanism in at least one position of the needle when it is withdrawn from the work and includes control means connected to the pulse generator and the counter and connected to the memory which contains the digital data. The reversing arrangement can be switched to the oscillator when the sewing machine is at a standstill for supplying pulses to the counter. In this way the preset feed execution is ended after each stopping process, thus preventing a faulty feed at the beginning of the next stitch.
A position correction of the workpiece relative to the needle, not hitherto possible in sewing machines with feed drives, can be realized by a circuit arrangement, wherein the oscillator is switchable via a switch, circumventing the counting device.
According to other features of the invention, rotation means are provided for rotating the work or workpiece about the needle. The feed wheel cooperates as part of the rotating means with pulses being supplied to the step motor for moving the feed wheel, both when the needle is inserted in the workpiece and when it is withdrawn from the workpiece. A sensor may also be provided which scans the edge of the workpiece at a measuring point disposed laterally before the stitch formation point.
In this way curved seams can be produced automatically according to a predetermined program, or edge-parallel seams can be made by scanning the edge of the workpiece.
As compared with known solutions (U.S. Pat. Nos. 3,080,836 and 3,472,187), a separate rotating device and the entire drive thereof thus become superfluous. This results in an arrangement which, besides the mechanical parts required for the normal feed, requires no other cost for parts. This solution is thus extremely simple and inexpensive.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the sewing machine according to the invention is illustrated in the drawings wherein:
FIG. 1 shows an overall view of a sewing machine equipped with a feed device, partly in section;
FIG. 2, an enlarged side view of the sewing machine according to FIG. 1, partly in section;
FIG. 3, a section along line III--III of FIG. 2;
FIG. 4, a section through a part of the roll foot drive mechanism, on a larger scale;
FIG. 5, an enlarged partial view of the stitch formation zone of the sewing machine according to a special form of realization; and
FIG. 6, a block diagram of the electronic circuit for the feed device.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIG. 1, the sewing machine consists of a base plate 1, a column 2, a standard 3, and arm 4 and a head 5 which together form a housing. In arm 4 a main shaft 6 is mounted in the usual manner for rotation. It is driven via a V-belt 7 by a motor (not shown) attached below the base plate 1. By a toothed belt 9 a rotary hook shaft 10 which is mounted in the base plate 1 and which is in driving connection with a rotary hook (not shown) is driven from the main shaft.
The main shaft 6 drives, via a crank 11 and a link 12, a needle bar 14 with needle 13. Link 12 is articulated to the needle bar 14 through a joint connection 15 (FIG. 2). The needle bar is mounted in a guide 17 secured on an axle 16 (FIG. 1). Axle 16 is mounted parallel to the main shaft 6 in arm 4 and is firmly connected to arm 4 by a screw 18.
In the lower part of column 2 (FIG. 2) a support 30 is mounted on an eccentric bolt 31 which has journals 34 and 35 protruding into bores 32 and 33 in column 2. Journal 35 is provided with a slot 36. Eccentric 31 is clamped on support 30 by a screw 37. Mounted in support 30 is a vertical shaft 38, which is guided and held in the axial direction by an adjusting ring 39 and a coupling 40. At the lower end the support 30 is equipped with a flanged plate 41 on which a step motor 42 is secured whose output shaft 43 is rigidly coupled to the vertical shaft 38 by coupling 40. At the upper end the vertical shaft 38 carries a pinion 44 of a spiroid gearing 45, the ring gear 46 of which is firmly connected to a sliding wheel 47 which is mounted by ball bearings in known manner and has an inner part with an axle end 48. The axle end 48 is received by a bore in an arm 30a of support 30 and can be clamped by a screw 49 after adjustment in the axial direction.
By rotation of the eccentric bolt 31 with the aid of slot 36, the sliding wheel 47 is adjustable in its height position relative to a stitch plate 50 via the support 30, which stitch plate terminates the column 2 at the top, and through which wheel 47 protrudes through a slot 50a in plate 50.
By a screw 51 in its upper part passing through a slot 52 in column 2, the support 30 is clamped to the column after it is adjusted. The lateral position of the sliding wheel can be aligned with slot 50a in stitch plate 50 using axle end 48 and screw 49.
In head 5 of the sewing machine, a vertical shaft 53 is mounted loose for axial motion and rotation. A clamping piece 54 is screwed to shaft 53. It has a radial bore into which a pin 55 has been pressed. Furthermore a coupling piece 56 is mounted loosely on shaft 53. A lug 57 extending laterally away from it, protrudes through a slot in head 5 and secures the coupling piece 56 against rotation. In its lower region the coupling piece 56 is formed as an annular sector and embraces therewith the clamping piece 54. The annular sector has a recess 59 into which the pin 55 protrudes and which terminates at one end in a ratchet groove 60, while at its other end recess 59 ends with a wall 61. A compression spring 62 which braces itself against a set ring 63 fastened on shaft 53, presses the coupling piece 56 and hence the upper wall of its annular sector, lightly downwardly against pin 55.
Resting on lug 57 (FIG. 3) is the free end of a leaf spring 64, which is secured in arm 4 and pushes the coupling piece 56 downward. Below lug 57 a lever arm 65 of an angle lever 66 mounted in head 5 protrudes. Lever 66 is connected via a link 67 to a lifting linkage (not shown) to be activated by the operator. Under the lever arm 65, a cam 68 is fastened on a shaft 69 mounted in head 5. Shaft 69 (FIG. 2) carries on its outwardly protruding end, a hand lever 70. At the lower end of shaft 53, a block 71 is fastened which has a groove guideway 72. In the guideway 72, an angular slotted lobe 73 is screwed tight, which is firmly connected to a roll foot support 74. The support 74 has a tubular piece 75 (see also FIGS. 3 and 4), terminating in a downwardly protruding end piece 76. In the end piece 76 a bore for attachment of an axle end 78 of a ball-bearing roll foot 80 by a screw 79 is provided. The roll foot 80 has a race 81 to which a ring gear 82 of a spiroid gearing 83 is firmly connected. The pinion 84 of spiroid gearing 83 is in engagement with the ring gear 82, eccentrically. A tubular support 85 is received in the tubular piece 75, which is clamped in its position by screws 86 screwed in the tubular piece 75. The support 85 consists of a tube 87, a hollow cylinder 88 continguous toward the top, and an annular end flange 89. In tube 87, a shaft 90 is mounted which carries at its lower end the pinion 84 and is firmly connected to a ring shoulder 91 which abuts against the lower end of tube 87.
Shaft 90 is embraced in the region of its upper end by the inner race of a ball bearing 93 pressed into the hollow cylinder 88. The upper end of shaft 90 is rigidly coupled, by a coupling 94, to an output shaft 95 of a step motor 96, the housing of which is screwed tight on the end flange 89.
On the main shaft 6 (FIG. 1) of the sewing machine a strobe disk 100 is mounted which has two pulse tracks, each cooperating with a pulse generator 101, 102. One track has a plurality of pulse markers 103 uniformly distributed on its circumference (FIG. 6), while the other track has only one pulse marker 104 passing by the pulse generator 101 when the needle 13 emerges from the workpiece.
The pulse generator 101 is connected to a control unit 105. Control unit 105 is connected to a reversing arrangement 106 via a control line 106a and, via control lines 108a and 109a to AND elements 108 and 109. A bus line 110 connects counting devices 112 and 113 to unit 105. Further there are connected to the control unit 105, via a bus line 114a a key panel 114, via a bus line 115a a display unit 115, and via a bus line 116a a data memory 116.
The outputs of the counting devices 112 and 113 are connected to inputs of power stages 118 and 119 for the associated step motors 42 and 96. Further, the outputs of the counting devices 112 and 113 are connected to the control unit 105 via lines 112a and 113a. Lines 118a and 119a lead from the control unit 105 to the power stages 118 and 119. Also connected to the control unit 105 are three further switches 120, 121 and 122, of which switch 120 serves to actuate a backward sewing process, while the two switches 121 and 122 are provided for slow drive of the step motors 42 and 96 in forward and backward directions with the sewing machine standing still, preferably in a needle-up position. To this end an oscillator 123 is connected to the two power stages 118 and 119 via a divider 124 and a switch 125. Switch 125 is connected to the control unit 105 via a control line 125a In addition, oscillator 123 is connected to the input E1 of the reversing arrangement 106, the input E2 of which is connected to the pulse generator 102. The output of the reversing arrangement 106 leads to the inputs El of the two AND elements 108 and 109, the outputs of which are connected to the respective counting devices 112 and 113, which are designed as down counters and which are presettable singly by the control unit 105 via the bus line 110.
With the key panel 114, one can preselect the number of steps of the step motors 42 and 96 to be executed per sewing stitch and hence the feed length of the individual transport organs-sliding wheel 47 and roll foot 80--between each stitch formation, with the possibility of setting different feed amounts of the sliding wheel 47 and of the roll foot 80. The preselected stitch length is indicated in the display unit 115.
The device operates as follows:
Using the key panel 114 the operator sets the desired feed amounts of the sliding wheel 47 and of the roll foot 80, corresponding digital values being taken out of the data memory 116 via the control unit 105 and thereby the counting devices 112 and 113 being preset. At the same time values corresponding to the feed amounts are indicated in the display unit 115.
During operation of the sewing machine, the sewing motor (not shown) drives the main shaft 6 over V-belt 7, which moves the needle bar 14 up and down via the drive connection of crank 11 and link 12. In addition the rotary hook drive shaft 10 is driven over toothed belt by the main shaft 6 to drive the shuttle (not shown). The drive for advance of the workpiece is actuated via the pulse generator 101 whenever the needle 13 leaves the workpiece. The pulse generator 101 then delivers a pulse to the control unit 105. Via the control lines 108a and 109a, the control unit now switches the potential at the inputs E2 of the AND elements 108 and 109 to H (high), so that the pulses originating thereafter from the pulse generator 102 are allowed to pass from the AND elements 108 and 109 to the counting devices 112 and 113 via the reversing arrangement 106 switched to input E2 during drive of the sewing machine.
When one of the counting devices 112 or 113 has reached the status "0", it delivers a control pulse to the respective power stage 118 or 119, whereby the corresponding step motor 42 or 96 is advanced by one step. At the same time this counting device 112 or 113 delivers, via the associated control line 112a or 113a, pulses to the control unit 105, which again presets this counting device 112 or 113 to a new value. The control unit 105 calls the corresponding values out of the data memory 116. At the same time the control unit 105 determines, via the control lines 118a and 119a connected to the power stages 118 and 119, whether the particular step motor 42 and 96 is being rotated forwardly or backwardly. The values presettable at the counting devices 112 and 113 are chosen so that the step motors 42 and 96 can execute their maximum number of steps within the withdrawn phase of the needle 13.
The stepping pulses acting on the step motors 42 and 96 drive the sliding wheel 47 and the roll foot 80 for joint transport action on the workpiece. By the vertical shaft 38 which is firmly coupled to the step motor output shaft 43 and by the miter gear 45, the step motor 42 drives the sliding wheel 47, while the step motor 96 at the same time drives the roll foot 80 via the shaft 90 firmly coupled to the step motor output shaft 95 and over the miter gear 83.
After the individual step motors 42 and 96 have traveled the number of steps set on the key panel 114 and depending on the correspondingly called data values from the data memory 116, the input E2 of the respective AND element 108 or 109 is switched to L (low) potential by the control unit 105 via the control line 108a or 109a, so that by the corresponding AND element 108 or 109, further passage of the clock pulses from the pulse generator is suppressed.
For backward sewing, for example for making a bar at the end of a seam, switch 120 is actuated, whereby, at the beginning of a new pulse from the pulse generator 101 via the control lines 118a and 119a at the power stages 118 and 119, the control unit 105 reverses the direction of movement of the step motors 42 and 96, so that they drive the sliding wheel 47 and the roll foot 80 in reverse direction as long as the actuation of switch 120 lasts. The execution of the step sequence of the step motors 42 and 96 occurs by calling the respective values set in the key panel 114 out of the data memory 116 in the manner described above.
During the stopping process of the sewing machine, which usually ends in the upper dead center of needle 13, the control unit 105 switches the reversing arrangment 106 to input E1, so that the pulses delivered by oscilator 123 are applied to the inputs E1 of the AND elements 108 and 109. As soon as the sewing machine stops, clock pulses from oscillator 123 are thus placed on the inputs E1 of the AND elements 108 and 109, instead of the clock pulses from the pulse generator 102. In this manner the preselected advance of the sliding wheel 47 and of the roll foot 80 is completed also after the last emergence of the needle 13 from the work, so that needle 13 is already above the next needle insertion point. As soon as the end position of the preselected feed amount has been reached, the control unit 105 turns the AND elements 108 and 109 off via the control lines 108a and 109a.
To correct the position of the workpiece relative to needle 13 when the sewing machine is stopped, slow transport of the workpiece in the forward feed direction while the sewing machine is turned off is possible by actuation of switch 121, and slow transport of the work in the backward direction is possible by actuation of switch 122. Actuation of the respective switch 121 or 122 brings about a closing of switch 125 via line 125a, so that pulses delivered by oscillator 123 and forwarded in reduced frequency from the divider 124, are sent to the two power stages 118 and 119, whereby the two step motors 42 and 96 are driven slowly for the drive of the sliding wheel 27 and of the roll foot 80. The movement direction of the step motors 42 and 96 is then set for forward or backward rotation via the control lines 118a and 119a at the power stages 118 and 119, depending on the actuation of switch 121 or 122.
The roll foot 80 is lifted off the work by turning the hand lever 70, with the cam 68 thus raising the coupling piece 56, via lever arm 65 of angle lever 66, over the lug 57 counter to the pressure of leaf spring 64. The same effect results also by actuation of the lifting linkage (not shown) which rotates the angle lever 66 via link 67.
Via the compression spring 62 the coupling piece 56 raises shaft 53 with the roll foot 80 fastened thereto and with the support 85, with the compression spring 62 ensuring the abutment of pin 55 in the ratchet groove 60 counter to the force of the compression spring 62, and shaft 53 can be rotated until the abutment of pin 55 on wall 61 of recess 59.
In a special form of the sewing machine, the sliding wheel 47 and roll foot 80 transport the workpiece during the operating cycle automatically by means of a process program called by the control unit 105 out of the data memory, which program controls the feed between two insertions of needle 13 into the workpiece in the above described manner and which moreover conveys to the two step motors 42 and 96, in the phase when needle 13 is inserted in the workpiece, a predetermined number of pulses in the same manner as during feed. This exerts a rotating action on the workpiece about the needle 13. This requires a second pulse marker 104, which then causes a pulse of the pulse generator 101 when needle 13 enters the workpiece.
Through the drive of sliding wheel 47 and roll foot 80 during the inserted phase of needle 13, a direction-of-rotation correction of the workpiece around needle 13 occurs during each inserted phase of needle 13 depending on the given sequence program.
In a further form of the sewing machine, there is provided for the scanning of the edge of a workpiece W (FIG. 5) a scanning arm 128 which is fastened on a shaft 129 of a potentiometer 130 carried by a yoke 131 on head 5. At its free end the scanning arm 128 is designed as a sensor 128a which, by the action of a torsion spring 132, applies against the edge of the workpiece W. The point of contact of the sensor 128a is arranged before the stitch hole 50b and laterally thereof. A pin 133 provided in yoke 131 serves for abutment of the scanning arm 128 when there is no workpiece W. The potentiometer 130 (FIG. 6) is connected to the control unit 105 via an amplifier 134.
During the operating process, the sliding wheel 47 and roll foot 80 transport the workpiece W automatically for execution of an edge-partial seam. With needle 13 withdrawn, the sliding wheel 47 and roll foot 80 execute the set amount of feed. The sensor 128a is then pressed by the torsion spring 132 against the edge of the workpiece S. In accordance with the respective form of the edge before the stitch formation point, the scanning arm 128 is subjected to a pivoting movement which rotates shaft 129 of potentiometer 130 from its zero position. The deviation picked up by potentiometer 130 are supplied via amplifier 134, as positive or negative values, to the control unit 105 which, in the phase of needle 13 inserted in the workpiece W, controls a number of stepping pulses corresponding to this deviation to the two step motors 42 and 96. Depending on positive or negative deviations, the step motors 42 and 96 are driven in forward or backward direction. With the advance of the workpiece W taking place laterally of the point of insertion of needle 13, the needle 13 serves as pivot, so that the workpiece W is rotated in such a way that the seam is always made at equal distance from the edge. The sewing process thus consists of a sequence of alternating feed and rotating processes.
Instead of a mechanical edge sensor, of course, photoelectric or other sensors may be used, without changing the essence of the invention.
While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. | In a sewing machine with a feed device which comprises a feed wheel arranged next to a stitch formation point, driven synchronously with stitch formation tools, and mounted in a support provided at the housing of the sewing machine, in order to obtain an extremely exact drive in both directions, the feed wheel is placed in driving connection with a step motor. In a manner known in itself, the step motor receives stepping pulses which can be generated by a pulse generator operating synchronously with a main shaft of the machine and via a counting device that determines the feed amount. This feed amount is presettable by selectable digital data contained in a memory. In an arrangement wherein the feed wheel is connected to its drive via a deflection gearing and a transmission shaft mounted in the support, the deflection gearing consists of a ring gear attached to the feed wheel and of a pinion firmly connected to the transmission shaft. An especially compact solution results by attachment of the step motor on the support and by rigid coupling of its output shaft to the transmission shaft. | 3 |
FIELD OF THE INVENTION
This invention relates to means for transporting tools and instruments to locations inside pipes, well holes and other such passageways, and to means for providing power or data connections to these tools.
BACKGROUND OF THE INVENTION
There are many applications in which it necessary to transport a tool or instrument far into a narrow passageway such as an oil well hole, a pipeline or a waterline, and in which an energy or information transmitting conduit such as an electrical cable is connected to the tool and extends outside the passageway. The passageways may be not be vertical, and they may curve along their length. Therefore the means for moving the tool will have to be able to exert a lengthwise force on the tool, both pushing it into and pulling it out of the passageway. The means must also be flexible enough to accommodate the passageway curves.
A method typically used in oil and gas wells is to connect the tool to flexible tubing, with the conduit inside the tubing. The conduit is housed in a flexible polymer rod, the rod in turn being centered inside the tubing.
Such a flexible tubing system has disadvantages which include high manufacturing costs and problems related to the strength of the flexible tubing. The tubing can be crushed or its inner channel pinched off if bent too sharply. Both crushing and pinching off can sever the conduit. The flexible tubing has limited axial strength. Tubing often has a short stress cycle life, so it can be used for only a few well servicings. The conduit cannot be accessed for inspection or repair without cutting into the tubing.
There are also applications in which is desirable to have a conduit connected to equipment far into the passageway, while also having a rigid connection transmitting the force required to operate the equipment. An example is a downhole oil well pump, in which a downhole piston is connected to drive gear at the surface by a solid metal sucker rod. The surface gear moves the downhole piston up and down through the sucker rod. It would be useful to monitor pressure or other properties at the downhole piston while the pump is operating. Another example is pipe or tubing that rotates a tool, such as a drilling tool, in a passageway, for which it would be useful to monitor properties at the tool while it is rotating.
SUMMARY OF THE INVENTION
This invention seeks to overcome problems with the prior art. According to an aspect of the invention, there is provided a device for moving equipment. The device comprises a rod having a groove set in it extending along the length of the rod. A groove extends along the rod and inward into the rod from the rod outer surface. A transmission conduit extends along the rod within the groove. According to further aspects of the invention, the groove is wider deeper in the groove than at the rod outer surface and the groove width at the rod outer surface is smaller than the diameter of the transmission conduit.
The transmission conduit should be sealed in the groove against fluid flow along the groove between the transmission conduit and the groove in any case where pressure may be a problem. Preferably, the transmission conduit is sealed in the groove by a sealant, and the sealant occupies all of the groove that is not occupied by the transmission conduit.
The device is typically used in combination with a rod actuator coupled to the rod for moving and positioning the rod. The rod actuator may be a rod injector or rod rotator.
According to a further aspect of the invention, the rod has an elongated cross-section defining a curved rod outer surface, and the groove is located where the longest cross-section diameter intersects the surface. The rod may have a cross-section forming the shape of an ellipse having a major axis, and the groove is located where the major axis intersects the rod surface.
According to a further aspect of the invention, there is provided apparatus for use in a well, the apparatus comprising a rod having an outer surface, the rod extending between a first end and a second end, a downhole tool being mounted on the first end of the rod, the second end of the rod being outside the well, a groove along the rod between the first and second ends and extending inward from the rod outer surface, a transmission conduit extending along the rod and sealed within the groove, the transmission conduit being connected to the downhole tool and extending to the second end of the rod, and a rod actuator coupled to the rod for moving the rod and downhole tool in the well.
According to a further aspect of the invention, there is provided a method for installing a transmission conduit in a groove along the length of a rod, the rod having an outer surface and the groove extending inward from the rod outer surface, comprising the steps of:
installing the transmission conduit in the groove from the rod outer surface; and
sealing the rod in the groove.
According to a further aspect of the invention, there is provided the method step of reducing the groove width at the rod outer surface so the transmission conduit is retained in the groove.
BRIEF DESCRIPTION OF THE DRAWINGS
There will now be described preferred embodiments of the invention, with reference to the drawings, by way of illustration only and not with the intention of limiting the scope of the invention, in which like numerals denote like elements and in which:
FIG. 1 is a schematic of the invention and shows it used for the particular application of downhole servicing of an oil or gas well.
FIG. 2 is a lengthwise cross-section view of the rod.
FIG. 3 is a lengthwise cross-section view of the rod.
FIG. 4 is a schematic a preferred embodiment of the invention comprising equipment at the well hole entrance for rotating the rod.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
In this patent document, “comprising” means “including”. In addition, a reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present.
FIG. 1 shows a preferred embodiment of the invention 10 used for servicing an oil or gas well downhole. A continuous rod 12 is attached to a well tool or instrument 14 . A guide 16 positions the rod 12 at the well hole entrance. A rod injector 18 at the entrance to the well hole 20 feeds the rod 12 into or out of the well hole 20 . The rod injector 18 is preferably a modified caterpillar flexible tubing injector, which uses flexible belts to effect the traction and thrust necessary to hold and move the rod 12 . Various caterpillar rod injectors are known in the art and need not be further described here. The guide and rod injector are supported and positioned by the mast 22 on the service truck 24 . The guide is suspended from the mast by a cable 26 and the rod injector 18 is mounted to the mast 22 by a strut 28 . Various forms of rod actuator may be used to move the rod within a well, such as a rod injector, or, as described below, a rod rotator.
The cross section of the rod 12 is shown in FIG. 2 . The conduit 30 is housed in a groove 32 extending radially inward from the outer surface of the rod 12 . The groove width is narrower at the rod 12 outer surface, and is wider towards the center of the rod 12 . The groove 32 can be made by machining or milling a cut or cuts into the rod 12 . The rod shown has a circular cross section, however other cross section shapes can be used to suit the application. FIG. 3 shows an elliptical cross section rod 34 , with a groove 32 at the tightest curvature region of the surface. The rod 12 can also be hollow centered, it strength requirements so allow.
The conduit 30 is installed in the groove 32 by inserting it at the rod 12 outer surface. The rod 12 is then cold rolled to reduce the groove width at the outer surface and thereby trap the conduit 30 in the groove 32 . The width of the groove 32 at the rod outer surface is therefore preferably the minimum that will allow the conduit 30 to be so inserted. For a flexible conduit 30 , the width of the groove 32 at the outer surface should be the same as or slightly smaller than the conduit 30 outer dimension. A hardenable sealant is then injected into the groove 32 , so it fills and forms a seal in the remaining volume in the groove 32 . Such sealing prevents fluid from leaking lengthwise via the groove, and is required in oil and gas wells for blow-out protection. The hardenable material is a viscous liquid when injected, and it then hardens to a semi-rigid or plastic state. A preferred sealant is Permatex™ Form-A-Gasket™, manufactured by Loctite Canada Inc., specification #81310, a silicon, room temperature vulcanizing compound. It will maintain sealing to about 300° C. Oil and gas well downhole equipment typically encounters high temperatures. Other room temperature vulcanizing compounds can be used, also. The hardenable sealant can also help hold the conduit 30 in the groove 32 .
The conduit 30 can be any type that will transmit energy or information. Conduit types therefore include electrical power cable, electrical signal cable, fibre optic cable, and hydraulic line.
This device improves upon the problems discussed above for coiled tubing. The rod is much more resistant to crushing or pinching off. The rod has much higher axial strength, so it can be used in more applications and has a longer life. Manufacturing costs are lower for the rod. The conduit is accessible for inspection and maintenance, and faulty conduit sections can be more easily repaired.
The rod is stored on spools similar to those for coiled tubing. Rod material used includes 41-30 steel. Other materials would be suitable, providing they have the required flexibility and axial strength, and the required groove can be made in them.
The grooved rod and conduit embodiment may be used for transmitting force or torque to operate a downhole tool, as discussed above. It may be used as the sucker rod for a downhole oil well pump, in which the conduit would transmit downhole pressure transducer signals to the surface while the pump is operating. FIG. 4 shows an embodiment for rotating a downhole tool 14 . The rotation gear 36 is used to rotate the rod 12 , which in turn rotates the downhole tool 14 about its longitudinal axis 38 . A drive head can be used as the rotating gem. A drive head comprises a motor that rotates a rotating table using belt or worm gear coupling. The rotating table is mounted on the rod 12 , co-axially with the rod longitudinal axis 38 . Drive heads and other rotation gear are known in the art and need not be further described here. A slip ring assembly 39 can be used for an electrical connection to the conduit 30 . A rotating seal can be used for a connection to a hydraulic line in the conduit 30 . Slip ring assemblies, rotating seals and other such electrical and fluid line connections are known in the art and need not be further described here.
The grooved rod and conduit embodiment has other applications besides use in passageways. It is useful in any application where the problems such as tangling would be caused by the conduit contacting other equipment. It is also useful for protecting conduit from sharp objects and other such hazards.
A person skilled in the art could make immaterial changes to the exemplary embodiments described here without departing from the essence of the invention that is intended to be covered by the scope of the claims that follow. | A device for moving a tool lengthwise in a passageway such as a pipe or oil well hole, with a power or signal conduit connected between the tool and outside of the passageway, consists of a solid rod with a groove along the rod's length, the groove extending inwards from the rod outer surface. The conduit is installed in the groove. The device can also be used to rotate the tool in the passageway. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a process and a device for controlling at least one twine guide arm in a pickup baler for wrapping cylindrical bales.
Such a baler, as described in publication FR-A-2 541 560 provides for picking up of windrows and rolling them into a spiral within an expandable baling chamber until the bale completely fills the same.
The bale is then surrounded by a twine helically wound around the bale and then ejected from the baler.
The wrapping or tying of the bale requires sustained attention on the part of the baler driver. On the one hand, the twine guide arm must be correctly placed at the beginning of the tying process and, on the other hand, the movement of the arm must be slow enough for winding the twine around the bale a number of times sufficient to render the bale compact.
2. Description of Related Art
French publication FR-A-2 442 577 describes a baler in which the guide arm is pivoted by means of a traction cable operated by the driver.
Tying devices are also known in which the guide arm is moved in a back and forth movement by a motorized control device, manual intervention possibly being necessary to adjust the speed of the motor or to stop it.
To overcome this drawback, French publication FR-A-2 414 295 provides means for controlling the movement of the guide arm by the bale itself when the latter has reached a predetermined size. For this purpose, the bale actuates a device for actuating a gear motor provided for controlling the tying device.
U.S. patent specification No. 4 649 812 discloses a hay baler of the kind considered herein, which is provided with a twine guide control mechanism having a control cam. Said cam by the action of which the wrapping or tying process is controlled is rotated stepwise by a motor-driven crank that permanently cooperates with a gear integral with said cam.
The present invention is aimed, i.a., at providing a structure wherein the cam can be conveniently engaged or disengaged kinetically with respect to the remainder of the tying control mechanism under the control of means for measuring the diameter of the bale being formed.
The object of such arrangement is to provide control of at least one twine guide arm in such a manner that a bale is tied automatically when, in the course of its formation in the baler, it has reached a predetermined diameter.
SUMMARY OF THE INVENTION
The invention is based on the idea of actuating at the least one twine guide arm by measuring the diameter of the bale supported by rollers which rotate said bale on which rests a tension arm associated with bale shaping belts.
According to the invention, at the end of the baling process, the distance between the tension arm and a bale driving roller constitutes the control parameter of cam actuating means adapted to displace a guide arm in a starting position for starting the tying process, where the rotating bale catches the twine whose part wound around the bale constitutes the control parameter for controlling said guide arm actuating means during tying.
The process thus defined is carried out by means of a mechanical control device, the movement and power of which are supplied by the bale supporting and driving rollers.
Other features and advantages of the invention will become apparent from the following description of an embodiment thereof which is given with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of the baler from which a part of the side wall has been removed to show the bale in the process of completion and the installation of the twine guide arm controlling device;
FIG. 2 is a side view of the device for controlling the twine guide arms during the process of shaping the bale;
FIG. 3 is a side view of the device in the state it reaches when the bale is completed;
FIG. 4 is a side view of the device during the process of distribution of the twine around the bale;
FIG. 5 represents the final position of the device after the distribution of the twine.
FIGS. 6 to 8, schematically show various positions of the twine guide arms during an operating cycle.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to FIG. 1, the hay baler shown is a baler known in the art and more particularly a tractor-drawn machine such as is commonly used in agriculture. It can be illustrated by the publication FR-A-2 541 560 filed in the name of the applicant.
The baler comprises a frame 1 supported on the ground through wheels 2, a shaping or baling chamber 3 into which e.g. hay is introduced in the form of a layer and then wound around itself about a horizontal axis XX', as well as a tying control mechanism 30 mounted on a wall 5 of the baler. Other characteristic parts of the baler are disclosed in detail in publication FR-A-2 541 560.
Frame 1 essentially comprises two side walls 4, 5 which limit the crosswise extent of shaping chamber 3 and carry the support of tying mechanism 30.
At the back of the stationary frame a door 8 supporting return rollers of a set of belts is pivoted on a pin or axle 7 and its opening and closing can be controlled by jacks or equivalent means (not shown), and it ensures the discharge of the bale at the end of the shaping or winding and tying cycle thereof. The front part of the frame carries a toothed pickup element 9 rotating in the direction of arrow F1. During the forward movement of the baler, pickup element 9 picks up harvest windrows 10 and conveys them into machine after they have come into contact with a notched feed roller 11 rotating in the same direction.
Two sets of belts 12 and 13 supported by return rollers comprise in a manner known per se a plurality of parallel belts distributed over the width of the baler. The sets of the belts 12 and 13 are driven by driving rollers such as 14 driven by a belt or chain transmission from a transmission housing which receives the movement by a drive shaft connected to the power takeoff shaft of the tractor. Driving roller 14, the set of belts 12, the corresponding return rollers of this set and certain return rollers of the set of belts 13 are mounted on the stationary frame, while other return rollers of the set of belts 13 are carried by door 8.
A tension arm 18 pivotally mounted on a pin 19 carried by the stationary frame supports two rollers 20, 21 respectively resting on the of sets of belts 12, 13. Support rollers 20, 21 delimit a slot for passage of sets of belts 12, 13. The sides of the belts located between driving roller 14, support rollers 20, 21 and notched roller 11 partly delimit shaping chamber 3.
The tying device consists essentially of two guide arms 23, 24 which are in tubular form and are mounted to pivot around a YY' axis under the action of a control cable 25 to perform an alternating movement along the shaping chamber 3. For this purpose, arms 23, 24 are connected to a connecting or holding lever 26 which is pivoted about the YY' axis and the end of which is connected to cable 25. The other end of cable 25 is attached to the end of a control connecting rod 27 pivoted on a pin 28 carried by the wall of a housing 29 enclosing the control device of arms 23, 24. Moreover, the control connecting rod carries a driving roller 31 on which bears the profile 32 of an actuation cam 33. Cam 33 is mounted to rotate around a pin 34. Cam profile 32 has at least two radii of curvature R1, R2 (cf. FIG. 2) of which the smaller, R1, provides a position wherein roller 31 is immobilized and wherein consequently connecting rod 27 and arms 23, 24 are held in a fixed position. When the roller passes onto the larger radius of profile 32, said roller 31 and consequently connecting rod 27 and arms 23, 24 are mobile.
The steep change of the radius of curvature of profile 32 at the level of a protuberance 32' of the cam profile provides a modification of the position of roller 31 so that arms 23, 24 return to their initial position.
The cycle of the motion of guide arms 23, 24 as obtained by the varying relative position of cam follower or roller 31 are schematically shown in FIGS. 6 to 8.
FIG. 6 represents the starting or initial position of arms 23, 24, such as determined when cam following roller 31 rests on the R1 radius portion of cam profile 32. In this position connecting or holding lever 26 maintains arms 23, 24 at close proximity of one the side walls (referenced 4 in FIGS. 6 to 9) of the baler, said arms possibly being angularly offset with respect to each other by a small angle a.
FIG. 7 shows a first intermediate position of arms 23, 24 and associated lever 26, corresponding to a first phase of displacement of roller 31 on cam profile 32 while the latter passes from its radius R1 to its radius R2 portion at the location of its contact with roller 31.
FIG. 8 shows the final position of arms 23, 24 at the end of the cycle, corresponding to the moment when roller 31 reaches the radius R2 portion of cam profile 32. In this final position 23, 24 are substantially perpendicular to their starting position, twines 54, 55 have been wound about bale 3 over the entire axial length thereof and a severing mechanism schematically indicated at 61 is actuated in a manner known per se to sever the twines.
Thereafter roller 31 will leave the radius R2 portion of the rotating cam and engage again the radius R1 portion thereof, whereby arms 23, 24 and associated holding lever 26 are moved back into the initial or starting position schematized in FIG. 6 and the above-described cycle will start anew with a view to producing the following bale.
FIGS. 6 to 8 thus show the movement of guide arms 23, 24 which results when cam 33 is rotated. For this purpose, tension arm 18 is connected to a control cable 35 of a swing bar 36 mounted to rotate around pin 34. Swing bar 36 carries a retractable driving pin 37 able to drive a lever 38 for actuating cam 33.
The end of lever 38 is shaped as a ramp 39 for actuating a mechanism 40 forming part of the means for engaging cam 33 to obtain a rotation of the latter during the rotation of the completed bale, whereafter swing bar 36 remains at rest.
Mechanism 40 comprises a linkage consisting of a deformable assembly made up of levers 41, 42 one of which, 41, is pivoted around a pin 43 carried by housing 29 and the other of which, 42, has a bent shape. Levers 41, 42 are pivoted around the same pin 44 adapted to be moved radially under the action of connecting rod 45 for actuating a sector-shaped element 46 centered on cam 33 and which is mounted to rotate around pin 34.
Sector-shaped element 46 is also centered on a toothed coupling wheel 47 rotatively integral with the cam. Wheel 47 can be driven by a spring-loaded coupling pawl 48 pivoted on an arm 49 freely rotating around pin 34 of the cam. The back and forth movement of arm 49 between a position A shown in solid lines in FIG. 2 and a position B shown in dot-and-dash lines is controlled by a connecting rod and crank system 50 connected to the axis or pin of roller 14.
Moreover, bent lever 42 carries a stop 51 adapted to receive a roller 52 rotatively integral with a return pulley 53 of twines 54, 55 guided respectively by arms 23, 24. Roller 52 is in positive contact with lever 42 and for this purpose has teeth in contact with a rack zone 56 provided on the inner surface of the lever.
A stop 60 prevents the lever from engaging roller 52 during the rotation of cam 33.
The operating cycle of the device will be described below.
FORMATION OF THE BALE
(FIG. 2)
Connecting rod and crank system 50, driven by driving roller 14, actuates arm 49 in an alternating movement around pin 34.
COMPLETION OF THE BALE
(FIG. 3)
Driving roller 14 still actuates arm 49. The distance between driving roller 14 and tension arm 18 is maximum.
At the end of travel, tension arm 18 stretches cable 35. The traction on cable 35 is converted into a rotational movement of swing bar 36. Pin 37 of swing arm 36 drives lever 38 and consequently the cam-plus-toothed wheel 33, 47 unit. Due to the rotation of projection 32' of profile 32, connecting rod 27 moves to the center of profile 32 (radius R1) and slackening of cable 25 provides the prepositioning of arms 23, 24 at one end of the shaping chamber.
Twines 54, 55 are wound around return pulley 53, and the rotation movement of the bale imparted by roller 14 provides traction on the twines and rotation of pulley 53. The rotation of pulley 53 provides the vertical movement of bent lever 42 by means of roller 52.
START OF TYING
(FIG. 4)
Driving roller 14 moves arm 49 in alternating directions.
Lever 42 drives connecting rod 45 and sector-shaped element 46 around pin 34, roller 52 is stopped at stop 51 of lever 42, the latter being immobilized by engaging another stop 60.
Spring-loaded pawl 48 is engaged at each movement of arm 49 between position A and B.
Cam 33 moves step by step in accordance with the angular movement of toothed wheel 47.
Due to the modification of the radius of curvature of profile 32 between values R1 and R2, connecting rod 27 and consequently arms 23, 24 move along chamber 3.
END OF TYING
(FIG. 5)
Cam 33 continues is rotation under the action of the alternating driving movement imparted by arm 49. Cam 33 drives lever 38 whose ramp in turn pushes pin 44. Lever 42 is shown in another position such as that represented in FIG. 2 and sector-shaped element 46, pivoted in the direction of the releasing of pawl 48, prevents the cam from being driven under the action of driving roller 14 and arm 49.
The bale continues to rotate until twines 54, 55 are cut or severed. | A device for controlling at least one twine guide arm 23, 24 for tying cylindrical bales in a pickup baler. The twine guide arm 23, 24 is adapted to pivot under the action of a control cable 25 close to the bale resting on the driving roller 14, while a tension arm 18 acting on shaping belts 12, 13 rests on the bale. At the end of the bale forming process, the distance between the tension arm 18 and the driving roller controls elements 33, 38 for moving the guide arm or arms 23, 24 toward a starting position corresponding to the beginning of the tying. The portion of the twine which is wound around the bale is then caught during the rotation of the bale for constituting the control parameter for controlling a cam engaging mechanism 40 adapted to engage the guide arm actuating elements 33, 38 during the tying process. | 0 |
This is a continuation of application Ser. No. 689,886, filed Jan. 9, 1985, which is a continuation of application Ser. No. 579,283 filed Feb. 14, 1984, which is a continuation of application Ser. No. 265,003, filed May 20, 1981.
BACKGROUND OF THE INVENTION
The present invention relates to an integrated circuit, and more particularly to a memory integrated circuit of so-called CMOS type where different channel types of insulated-gate field-effect transistors are employed.
CMOS circuits have been widely used because of their low power consumption, in which P type and N type field effect transistors are employed. In general, a CMOS circuit arrangement is formed on a semiconductor substrate of a first conductivity type provided with well regions of a second conductivity type opposite to the first conductivity formed therein in order to arrange both of P and N channel transistors on the same semiconductor chip. In this arrangement, it is required to provide the substrate and the well region with ohmic contacts for potential sources (V CC potencial and V SS potential).
In the CMOS circuit, however, as is well known, a current triggered by an external noise voltage or the like flows through the substrate or the well region, and a voltage drop due to this current acts as a dominant factor deciding the degree of occurrence of a parasitic thyristor effect, that is, a so-called latch-up phenomenon causes in the CMOS structure. Accordingly, methods for preventing occurrence of this latch-up phenomenon have been performed such that a part of the well region or the substrate is made a low resistance layer by increasing the impurity concentration thereof, or the supplying of potential for the well region or the substrate is effected by performing the connection with a metal having a low sheet-resistance such as aluminum with a width as large as possible in layout.
However, with the recent increases in the memory capacity and in the density of the semiconductor memory circuit arrangement, it has been required to employ a fine patterning technique and/or bi-layer or stacked layers of polycrystalline silicon structure and the like. The above situation is the same for the CMOS memory circuit arrangement also, and particularly according to the layout of the group of memory cells, an extensive variation of chip size is caused. That is, although the mask pattern used for fabricating the circuit arrangement is subject to the fine patterning, the contact area between a power source wiring and the well region or the substrate cannot be simply reduced in view of the latch-up phenomenon. In addition, in the situation where the bi-layer polycrystalline silicon structure, for instance, the upper polycrystalline silicon layer containing N type impurities is used for a wiring for supplying the V SS power source, the direct ohmic electrical connection to a well region of a P-type or a substrate of a P-type is impossible, so that it is necessary that once the N doped polycrystalline silicon is connected with a metal such as aluminum, and further the metal is connected with the P type well or the P type substrate. As a result, although the bilayer polycrystalline silicon structure is incorporated for the purpose of effecting the high density of integration, the expected high density cannot be attained in a specified pattern, for instance, a group of memory cells because of the above mentioned indirect connection between the power source wiring and the well region or the substrate.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an integrated circuit having a high-density of circuit structure.
It is another object of the present invention to provide a semiconductor memory device provided with a large memory capacity.
It is still another object of the present invention to provide a CMOS circuit having a high integration and operable without causing latch-up phenomena due to stray thyristor effect.
It is still another object of the present invention to provide a CMOS type semiconductor memory device of a high-density and operable with a low power consumption.
An integrated circuit according to the present invention comprises a semiconductor substrate of a first conductivity type, at least one impurity-doped region of a second opposite conductivity type formed in the semiconductor substrate, and at least three stacked wiring layers, the lowest layer being formed of polycrystalline silicon and including silicon gates of transistors formed on the impurity-doped region and the substrate, one of the upper layers being formed of polycrystalline silicon for feeding a power supply to some of the transistors in the impurity-doped region and being connected to the impurity-doped region, and the other of the upper layer being formed of high-conductivity metal.
In the above integrated circuit, the polycrystalline silicon as the above one of the upper layers is doped with an impurity of the first conductivity so that good ohmic contact is obtained between an impurity region formed in the impurity-doped region and the polycrystalline silicon. While this polycrystalline silicon as the one of upper layers is connected to the impurity doped region through a PN junction in reverse-direction formed therebetween, it would appear to the ordinarily skilled artisan that the impurity-doped region cannot be biased by the power supply through the reverse-direction PN junction. However, such PN junction is favorably formed by contacting highly doped polycrystalline silicon and the highly doped contact region in the impurity-doped region and hence the PN junction is very leaky like a resistor. Therefore, the impurity-doped region can be well biased by the leakage current of the PN junction so that the latch-up phenomena may be effectively prevented.
According to the present invention, it is possible to obtain a CMOS memory circuit arrangement in which a polycrystalline silicon used for a power source wiring and a well region or a substrate, which contains an impurity of conductivity type opposite to that contained in the polycrystalline silicon, are connected with each other in a junction state under the realization that the latch-up phenomenon is comparatively hardly caused in the memory cell matrix.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a circuit diagram illustrating a memory cell of CMOS static RAM;
FIG. 2 is a plan view showing a conventional layout of a part of a memory cell matrix;
FIG. 3 is a plan view showing a part of a memory matrix according to one embodiment of the present invention;
FIG. 4 is a cross sectional view corresponding to a line a--a' of FIG. 4;
FIGS. 5A to 5C are plan views respectively showing detailed layout patterns of FIG. 1; and
FIGS. 6A to 6D are plan views respectively showing detailed layout patterns.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
First, with reference to FIG. 1, a general circuit structure of a CMOS type memory cell will be briefly explained.
In FIG. 1, a memory cell is composed of N-channel field effect transistors Q 1 to Q 4 and P-channel field effect transistors Q 5 and Q 6 . The transistors Q 3 and Q 5 form a first inverter while the transistors Q 4 and Q 6 form a second inverter. An output of the first inverter and an input of the second inverter are commonly connected at a node N 1 . An output of the second inverter and an input of the first inverter are commonly connected at a node N 2 . The transistors Q 1 and Q 2 respectively connected between a true digit line D and the node N 1 and between a complement digit line D and the node N 2 operate as transfer gates in response to a logic level of a word line WL.
In the following, the present invention will be explained by referring to accompanying drawings in comparison with the conventional technique, for example, in the situation where the V SS power wiring is formed of the polycrystalline silicon doped with the N type impurity and the substrate is of N type while the well region is of P type.
FIG. 2 shows a conventional layout of a memory cell matrix with respect to two memory cells A and B neighboring with each other. In this layout, one word line is formed of a laterally extended polycrystalline silicon 107. Portions 101 and 102 of the polycrystalline silicon 107 act as gates of the transfer gate transistors Q 1 and Q 2 in FIG. 1 for the memory cell A. Similarly, portions 103 and 104 of another word line 108 act as gates of the transfer gate transistors in the memory cell B. Layouts of flip-flop circuits formed of the mentioned first and second inverters in the cells A and B are indicated by reference numerals 105 and 106 respectively. True and complement digit lines D and D are formed of aluminum wirings 109 and 110 respectively. Next, V SS power wirings are formed of aluminum wirings 111a and 111b. High impurity-concentration P type diffusion regions 112a and 112b are employed for electrically connecting the P type well region 120 with the V SS power wirings 111a and 111b through openings provided on which region ohmic contacts are effected with the V SS power wirings 111a and 111b.
In the above conventional layout, it is impossible to reduce the pattern size of the memory elements because of the limit of space in the aluminum wirings of the V SS power wirings 111a and 111b the digit lines 109 and 110. For removing this difficulty, it may be thought that the bilayer polycrystalline silicon structure is incorporated into the memory matrix and the upper layer of polycrystalline silicon which is used for the V SS power wiring. However, it has been conventionally regarded as impossible to perform the connection for the P type well region with other than such a metal as aluminum or a polycrystalline silicon containing the P type impurity, because of the required function of suppression of the latch-up phenomenon.
In contrast thereto, according to the present invention, the above conventional concept is cleared away, and, under the realization that the latch-up phenomenon is comparatively hardly caused in the memory cell matrix, the polycrystalline silicon used for the V SS power wiring doped with N type impurity is directly connected to the above mentioned P type well region in the junction state, whereby the latchup phenomenon can be endured, and further the wiring limit caused by aluminum is removed, and the area occupied by the memory element can be reduced. As a result, the high density thereof can be attained.
With reference to FIGS. 3 and 4, an embodiment of the present invention will be described.
A P-type well region 220 for forming N-channel transistors is formed within an N-type semiconductor substrate 221. As is similar in FIG. 2, transfer gate transistors Q 1 and Q 2 of FIG. 1 are formed by the N-type polycrystalline silicon 207 as the word line, N type regions 216 and 217 as the nodes N 1 and N 2 of FIG. 1, and N type regions 218 and 219. To the regions 218 and 219 true and complement digit lines 209 and 210 formed of aluminum are connected through contact holes. The V CC wirings 222a and 222b are formed by a P-type region extended to drains of the transistors Q 5 and Q 6 of FIG. 1.
In this figure, the V SS wirings 211a and 211b are formed of a polycrystalline silicon which is formed on the layer above the silicon layer forming the word lines 207 and 208 and doped with an N-type impurity. The digit lines 211a and 211b are connected to N type regions 214a and 214b coupled to the sources of the transistors Q 3 and Q 4 through contact holes 215a and 215b, and this connection is performed by an ohmic contact between the same conductivity (N) type silicon layers 211a and 211b and region 214a and 214b. In other words, the conductivity type of the silicon 211a and 211b is determined so as to provide a current between the regions 214a and 214b and the V SS wirings 211a and 211b. The polycrystalline silicon wiring 211 are also directly connected to P + contact regions 212a and 212b formed in the P type well region 220 through a contact hole. The polycrystalline silicon wirings 211a and 211b are admitted to be superposed on a part of the digit line wirings 210 and 209 formed of aluminum.
Thus, continuous and simple wirings are provided from the starting point to the ending point of the memory cell matrix, and further an aluminum wiring for the ohmic contact with the P type diffusion layer can be avoided. With the polycrystalline silicon wirings 211a and 211b, so that the wiring limit caused by the aluminum V SS wiring can be removed, whereby the pattern area occupied by each memory cell can be reduced. Under this circumstance, it can be regarded equivalently that diodes 213a and 213b are inserted between the P type well 220 and the V SS power wirings 211a and 211b with a forward-direction from the P type well towards the V SS power wirings 211a and 211b.
In other words, in view of supplying the V SS power to the well region 220, the diodes 213a and 213b operate in a reverse-direction to block the current to the well region 220 and hence biasing of the well region 220 would not appear to be performed. However, rectifying the characteristics of the PN junctions of the diodes 213a and 213b are not ideal, but they rather act leaky like resistors. This seems to be caused by the junction between the highly doped N type polycrystalline silicon (211a and 211b) and the highly doped P + regions 212a and 212b. Therefore, the P-type well region 220 can be sufficiently biased by the diodes 213a and 213b.
Furthermore, in the case that these diodes are employed only for the memory cell matrix where the latch-up phenomenon is comparatively hardly caused, even if these diodes have insufficient current performance, many of similar diodes are connected in parallel in the memory cell matrix, and there is substantially no difficulty caused in practical use.
As is apparent from the above, according to the present invention, the high density integration of the CMOS memory circuit arrangement, particularly inside the memory cell matrix thereof, can be attained.
Next, with reference to FIGS. 5 and 6, a detailed layout example and the effect of the present invention in comparison with the conventional layout will be described.
In the following explanation, the same layout rule is applied to the layouts of FIGS. 5 and 6, where each contact hole is formed with a rectangular share of 2.4 μm×2.8 μm and aluminum wirings have their width of 3.7 μm. Polycrystalline silicon wirings as the word lines and interconnections in the flip-flop circuits are of 3.3 μm width. In FIGS. 5 and 6, the same reference numerals and codes are utilized to indicate portions as those of FIGS. 1 to 4 for better understanding.
Throughout FIGS. 5A to 5C which show the conventional technique corresponding to FIG. 2, marks "+" are used to indicate reference points for layout aligning.
The P well region 120 and the respective P and N type impurity-doped regions are shown in FIG. 5A, with respect to neighboring two memory cells. Areas denoted by Q 1 to Q 6 are channel regions corresponding to the transistors Q 1 to Q 6 of FIG. 1. FIG. 5B shows a layout pattern of the first level polycrystalline silicon with which the word lines 107 and 108 and interconnections 131 and 132 for forming the flip-flop circuit are formed. FIG. 5C shows a layout of aluminum wirings 109 and 110 as the digit lines D and D, and the V SS lines 111a and 111b. Wirings 141 and 142 are to connect the polycrystalline silicon wirings 131 and 132 to the P type and N type regions with ohmic contacts.
As shown in FIG. 5C, in the conventional layout of the memory cell matrix corresponding to FIG. 2, each of the memory cells is arranged in a rectangular region having a length of 37 μm and a width of 41.4 μm. In this region, wirings 151 and 152 forming circuit connections as well as gates of the transistors Q 3 to Q 6 are made of the same level of polycrystalline silicon of N-type as the word lines 107 and 108.
With reference to FIGS. 6A to 6D, the detailed layout patterns of the respective layers according to the present invention will be described.
The layout of the P well region 220 and the respective impurity regions are shown in FIG. 6A.
The regions denoted by the reference codes Q 1 to Q 6 are the channel regions corresponding the transistors Q 1 to Q 6 of FIG. 1. The P type region 222 is used to feed the Vss power supply to the memory cells.
FIG. 6B shows a layout of the first level of the polycrystalline silicon forming the word lines 207 and 208, and the interconnection wirings 231 and 232 forming the flip-flop circuit of the memory cell.
FIG. 6C shows a layout of the aluminum wirings. The wirings 209 and 210 form the word lines D and D. The wirings 241 and 242 are contact connections between the wirings 231, 232 and the impurity regions.
FIG. 6D shows the second level of porycrystalline silicon introduced by the present invention. In this example, for reducing a resistance, the polycrystalline silicon 211 is formed in a mesh-like manner along the peripheral edge of the respective memory cells.
Through the contacts 215a and 215b, the polycrystalline silicon 211 is connected to the N type region 214 while, through the contacts 250a and 250b, the polycrystalline silicon 211 is lso directly connected to the P + contact region in the D well region 220.
As shown throughout FIGS. 6A to 6D, especially in FIG. 6D in the layout according to the embodiment of the present invention, each of the memory cells is formed on a relatively small region having a length of 37 μm and a width of 32.5 μm. In this layout, the wirings 251 and 252 for connecting the transistors Q 3 to Q 6 are formed of the same level of polycrystalline silicon as those for the word lines 207 and 208. As described above, according to the present invention, a reduction in size of about 22% can be achieved in the memory cell matrix without losing the latch-up phenomena suppression function.
Although the above embodiment is described regarding the situation where the V SS power wiring formed of the polycrystalline silicon with the N type impurity, the N type substrate and the P type well regions is employed, the matter can be similarly effected by connecting the P-type polycrystalline silicon with the N type diffusion layer forming a part of the N type well even in the situation where the V SS power wiring formed of the polycrystalline silicon doped with the P type impurity, the P type substrate and the N type well regions is employed instead. | A high-density integrated circuit employing different first and second channel types of insulated gate field effect transistors is disclosed, which comprises at least three stacked wiring layers, the lowest layer being formed of polycrystalline silicon and including silicon gates of the transistors, one of the upper layers being formed of polycrystalline silicon and used for feeding a power supply to some of the transistors and being connected to at least one well region on which the first channel type of transistors are formed, and the other of the upper layers being formed of high-conductivity metal. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] According to the preamble of claim 1 , the present invention relates to a percussion mechanism having an electrodynamic linear drive.
[0003] 2. Description of the Related Art
[0004] Drilling and/or striking hammers (designated “hammers” hereinafter) are standardly driven by electric motors in which a rotor rotates a drive shaft. The rotational movement is converted into an oscillating linear movement that is communicated to a drive element in a percussion mechanism. Here, as a percussion mechanism in particular a pneumatic spring mechanism is suitable in which a drive piston that acts as a drive element is moved back and forth.
[0005] From DE 102 04 861 A1, a pneumatic spring percussion mechanism is known for a hammer in which a drive piston is capable of being driven by an electrodynamic linear drive. The drive piston is coupled to a runner of the linear drive, so that the linear back-and-forth movement of the runner is transmitted to the drive piston. The movement of the drive piston is in turn transmitted (as is standard in pneumatic spring percussion mechanisms) via an air spring to a percussion piston that strikes the end of a tool or strikes an intermediately situated header in a known manner.
[0006] In a linear electromagnetic drive system of this sort, the runner and the drive piston coupled thereto must be braked when they reach their extreme positions in order to enable a change in the direction of movement. Only in this way is an oscillating percussive operation possible. During the braking, it, is possible to feed part of the kinetic energy back into an intermediate circuit as electrical energy. However, in the coils of the stator that surrounds the runner, heat loss occurs that has an adverse effect on the efficiency of the percussion system. In addition, the lost heat must be conducted away using a suitable cooling device.
[0007] It is therefore advantageous to intermediately store the kinetic energy of the drive unit made up of the runner and the drive piston in a spring, so that after the reversal of the direction of movement this energy is available for the counter-movement, and supports the electromagnetic drive force of the linear drive.
[0008] From each of EP 0 718 075 A1 and DE 24 19 164 A1, an electrodynamic drive is known for a percussion mechanism in which a return movement of a percussion piston is received by a mechanical helical spring acting as an end stop. When the percussion piston moves forward again, the helical spring releases the stored energy and thus supports the forward or percussive movement. The described percussion mechanisms are however not pneumatic spring percussion mechanisms, and do not have any separation between a drive piston and a percussion piston.
[0009] In addition, helical springs have the disadvantage that they can break due to the high impact speeds. Also, significant vibration noise results. Moreover, if the helical spring is too weak, given a correspondingly high impact speed of the percussion piston the spring can bottom out, which can result in damage to the percussion mechanism.
[0010] DE 27 28 485 A1 indicates an electromagnetically operated percussion device in which a shaped piece that acts as a percussion tool is surrounded by a plunger that can be moved cyclically in the impact direction by an electromagnet. At the rear end of the percussion tool, a piston is provided that operates against a pneumatic damper.
[0011] From U.S. Pat. No. 1,467,677, an electric hammer is known in which a piston is actuated in alternating fashion by two electromagnets and is moved back and forth in this way. At one end of the piston there is situated a hardened steel tip that strikes a percussion tool. On the opposite side of the piston, an air spring is provided whose strength can be adjusted by opening and closing air ducts.
OBJECT OF THE INVENTION
[0012] The underlying object of the present invention is to indicate a percussion mechanism having an electrodynamic linear drive in which an electromagnetic drive force that is used to reverse the direction of movement of a linearly moved drive unit is supported without having to accept the disadvantages associated with other types of percussion mechanisms.
[0013] According to the present invention, this object is achieved by a percussion mechanism according to claim 1 . Advantageous embodiments of the present invention are indicated in the dependent claims. A percussion mechanism according to the present invention has an electrodynamic linear drive, a drive element that can be moved back and forth in a percussion mechanism housing by the linear drive, a percussion element that strikes a tool, and a coupling device that is effective between the drive element and the percussion element, via which the movement of the drive element is capable of being transmitted to the percussion element. According to the present invention, the percussion mechanism is characterized in that, seen in the direction of impact, a reversing hollow space is effectively provided before and/or after the drive element, and in that the reversing hollow space is capable of being separated at least at times from the surrounding environment, in such a way that in the reversing hollow space is capable of being separated at least at times from the surrounding environment, in such a way that in the reversing hollow space it is possible to produce a reversing air spring that acts against, the drive element and/or against the percussion element.
[0014] Correspondingly, according to the present invention it is provided that an air spring can be produced in front of and/or behind the drive element during the operation of the percussion mechanism. This reversing air spring, as it is called, is charged, or “tensioned” or compressed, by the movement of the drive element when the drive element moves in, the direction of the air spring or of the reversing hollow space that accommodates the air spring. When there is a reversal of the linear movement of the drive element, the air pressure, then prevailing in the reversing air spring exerts a force on the drive element that supports the reversal of the direction of movement and accelerates the drive element in the opposite direction.
[0015] It is not absolutely necessary for the reversing air spring to actually be spatially situated axially in front of or behind the drive element. The actual location of the reversing air spring situated in the reversing hollow space is, rather, arbitrary. However, what is important is that the action of the force of the reversing air spring be capable of being transmitted to the drive element (or percussion element), or, conversely, that the charging of the reversing air spring by the drive element (percussion element) be possible.
[0016] Air spring systems have proven their usefulness in percussion mechanisms, and have a very high degree of reliability. If designed properly, they also have a high degree of efficiency. A complete compression of the air spring, and thus an impact stress on the solid-body components that are moved relative to one another and that form the hollow space, can be avoided due to the progressivity of the spring characteristic (especially in the end area). The constructive length of the reversing air spring can correspondingly be made shorter than is the case in linear metal spring systems (helical springs). In addition, air springs produce less sound. In a particularly advantageous specific embodiment of the present invention, the drive element is connected to a runner of the linear drive and forms an integrated drive unit with the runner. In particular, it is advantageous if the drive element bears the runner or is essentially completely formed by the runner, so that the runner simultaneously takes over the function of the drive element.
[0017] The linear motor can be a switched reluctance motor (SR motor), and has in the area of movement of the runner a plurality of drive coils (stators) that are connected in a manner corresponding to the desired movement of the drive element. It is to be noted that in the context of the present invention an electrodynamic drive (e.g. in the form of a single electromagnetic coil) acting as a drive coil for the drive element is also regarded as a linear motor. The backward movement of the drive element can then take place for example exclusively via a reversing air spring that can be produced in a reversing hollow space that is present in front of the drive element.
[0018] In a specific embodiment, the coupling device is formed by a stop that is effective between the drive element and the percussion element. Via the stop, the drive movement of the drive element can be transmitted directly to the percussion element. A variant is possible in which the coupling device is formed by two stops that move the percussion element back and forth corresponding to the movement of the drive element.
[0019] Preferably, the coupling device is formed as an elastic, in particular spring-elastic, element that is effective in at least one direction between the drive element and the percussion element. In this way, it is possible to reduce the noise emission and mechanical stresses on the relevant components. As an elastic element, a coupling air spring (explained in more detail below) can be used. Alternatively, the above-described stops can be supplemented by an elastic element or provided with an elastic layer in order to deploy a spring-elastic effect.
[0020] In a preferred specific embodiment, the reversing hollow space is situated at one end of the drive element, between the drive element and the percussion mechanism housing, in particular between the drive unit and the percussion mechanism housing. The reversing hollow space can correspondingly also be situated at one end of the runner coupled to the drive element. The situation at one end makes it possible for the reversing air spring that can be produced in the reversing hollow space to act immediately on the drive unit and thus on the drive element.
[0021] It is particularly advantageous that the reversing air spring that can be produced in the reversing hollow space counteracts at least at times a movement of the drive element. In this way, the drive element can compress or charge the reversing air spring during its movement. After a reversal of the direction of movement of the drive element, the reversing air spring releases its stored energy and supports the counter-movement of the drive element.
[0022] Advantageously, the reversing air spring that can be produced in the reversing hollow space counteracts the movement of the drive element at least shortly before a reversal of direction of the drive element. In this way, the reversing air spring contributes to a braking of the drive element shortly before its reversal of direction. Depending on the dimensioning of the linear drive and of the reversing air spring, in some circumstances it is even possible in this way for a return movement of the drive element to be brought about solely by the reversing air spring, while the linear drive is switched off. Likewise, it is possible for the linear drive to control the return movement of the drive element with only low power. If necessary, for this purpose a sensor mechanism is to be provided that constantly determines the precise location of the drive element or of the runner and in this way monitors the action of the reversing air spring. With the aid of the sensor mechanism and a corresponding control unit, the linear drive can be controlled in such a way that the drive element and the runner follow a prespecified course of movement.
[0023] In a particularly preferred specific embodiment of the present invention, the reversing hollow space is a “first” hollow space that is provided in front of the drive element, a part of the percussive element passing through the first hollow space.
[0024] It is particularly advantageous if, alternatively or in addition to the first hollow space, a reversing hollow space is provided as a “second” hollow space behind the drive element, and, when there is a return movement, opposite to the direction of impact, of the drive element, the reversing air spring capable of being produced in the second hollow space is effective at least over a movement path of the drive element of greater than 30%, in particular greater than 50%, of the overall path of the return movement of the drive element.
[0025] Whereas above it was defined that a reversing hollow space is situated in front of the drive element as the “first hollow space,” the reversing hollow space behind the drive element is designated the “second hollow space.” These differing designations are intended only for clarification, and do not have any further meaning with respect to the functioning of the device. Both the first hollow space in front of the drive element and also the second hollow space behind the drive element act as “reversing hollow spaces” for accommodating a reversing air, spring that supports the respective reversal of direction of the drive element and the corresponding acceleration in the opposite direction. The first and the second hollow space can be provided in the percussion mechanism alternatively or together.
[0026] The relatively elongated effectiveness of the reversing air spring in the second hollow space means that the reversing air spring situated behind the drive element builds up over as long a path as possible, so that the drive unit has to exert force against this reversing air spring over almost its entire return path in order to compress this spring. While during the forward movement of the drive unit in the direction of impact it is sought to transmit as large a portion as possible of the drive energy to the percussion element, so that this portion of drive energy is available as impact energy, during the return movement of the drive unit there is a certain excess of energy, because during the return movement no impact is to be carried out. This excess of energy can now be used to charge the reversing air spring behind the drive element over as long a path as possible. The energy stored in the reversing air spring is then available for the next forward movement, and supports the effect of the linear drive for impact production. In this way, the linear drive can be made weaker, so that the power loss to be applied in the stator coils is also reduced.
[0027] The drive force produced by the coils is proportional to the current flowing through them, while the power loss in the coils is proportional to the square of the current. The impact or percussion energy is proportional to the product of the force times the path. If the path of the drive element is lengthened, the force that is to be produced by the linear drive, i.e. the stator coils, can be reduced in order to obtain the same energy effect. This increases the efficiency. Even if the air spring itself produces losses, the overall balance is positive compared to an electrical intermediate storage of the electrical braking energy in an intermediate circuit.
[0028] Preferably, there is provided a ventilation opening that can be closed at times between the reversing hollow space and the surrounding environment. Via the ventilation opening, it is possible to equalize the air between the reversing air spring in the reversing hollow space and the surrounding environment in order to compensate gap losses that necessarily occur during the compression phases.
[0029] Preferably, the ventilation opening is provided in the percussion mechanism housing in an area past which the drive element or drive unit travels during a percussion cycle. The opening and closing of the ventilation opening can in this way be immediately taken over by the drive element or drive unit itself, without requiring an additional control mechanism.
[0030] Correspondingly, it is particularly advantageous if the ventilation opening is capable of being opened or closed during a percussion cycle depending on the position of the drive element and/or of the drive unit.
[0031] A specific embodiment is particularly advantageous in which the percussion mechanism is realized as a pneumatic spring percussion mechanism. For this purpose, the drive element is fashioned as a drive piston and the percussion element is fashioned as a percussion piston. The coupling device is formed by a coupling air spring that acts in a coupling hollow space between the drive piston and the percussion piston. The coupling air spring ensures the transfer of energy from the drive piston to the percussion piston, and is responsible in a known manner for the designation “pneumatic spring percussion mechanism.” Pneumatic spring percussion mechanisms are known from the prior art in many embodiments. However, according to the present invention what is new is the possibility of braking the drive piston and/or the percussion piston using the additional reversing air spring. The coupling air spring can also be regarded as a main air spring, because a significant part of the impact energy is transmitted by it.
[0032] In a particularly advantageous specific embodiment of the present invention, the drive piston essentially encloses the percussion piston. The percussion piston has a piston head, and, relative to the forward-directed direction of impact, the coupling hollow space having the coupling air spring for transmitting the impact energy to the percussion piston is situated behind the piston head. In front of the piston head, another hollow space for a return air spring is formed between the drive piston and the percussion piston. Such a hollow piston percussion mechanism having a double-action air spring is known. Accordingly, the drive piston has a hollow cavity in which the percussion piston can move back and forth. The return air spring ensures a controlled return movement of the percussion piston after the impact. In this way, the percussion piston is connected in an entrained manner to the movement of the drive piston in its return movement as well.
[0033] In order to permit formation of the hollow space for the return air spring in front of the piston head, it is necessary that the drive piston enclose the percussion piston not only in the rear area, i.e. in the area of the main air spring, but also in the front area in front of the piston head. Only a shaft of the percussion piston extending from the piston head can be led out from the drive piston.
[0034] In a preferred specific embodiment, the reversing air spring acts only against the drive piston, and not against the percussion piston. In this way, the percussion piston is freely movable and receives all of its kinetic energy via the coupling to the drive piston.
[0035] In another specific embodiment of the present invention, however, the reversing air spring additionally acts at least in a direction of movement of the percussion piston, or may even act only against the percussion piston. In this variant, in particular during its return movement the percussion piston can run against the reversing air spring and charge it, so that the reversing air spring, which is not coupled to the drive piston, supports the subsequent forward movement of the percussion piston.
[0036] In such a specific embodiment, it can be advantageous if the percussion piston is connected with a positive fit to a reversing piston, so that the reversing piston acts against the reversing air spring. It is then possible to situate the reversing air spring at a location remote from the percussion piston.
[0037] In another specific embodiment of the present invention, the reversing air spring acts at least at times axially against the drive element or against the percussion element, the reversing hollow space being provided in an area that is not situated axially to the drive element. For this reason, a transfer device is provided with which the drive element can be coupled non-positively to the reversing air spring formed in the reversing hollow space. The reversing hollow space can in this way be situated for example laterally next to the drive element or in another area of the percussion mechanism or of the hammer driven thereby.
[0038] This specific embodiment enables the free situation of the reversing air spring at a location at which there is suitable space for it. Thus, the reversing hollow space with the reversing air spring can for example be situated, next to the drive element.
[0039] These and additional advantages and features of the present invention are explained in more detail below on the basis of examples, with the aid of the accompanying Figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] FIG. 1 shows a schematic view of a section through a percussion mechanism, realized as a pneumatic spring percussion mechanism, according to a first specific embodiment of the present invention, having a drive unit in the extreme rear position;
[0041] FIG. 2 shows the pneumatic spring percussion mechanism of FIG. 1 with the drive unit in the center position;
[0042] FIG. 3 shows the pneumatic spring percussion mechanism of FIG. 1 with the drive unit in the extreme front position;
[0043] FIG. 4 shows a schematic view of a section through a percussion mechanism, realized as a pneumatic spring percussion mechanism, according to a second specific embodiment of the present invention, having a drive unit in the extreme rear position;
[0044] FIG. 5 shows the pneumatic spring percussion mechanism of FIG. 4 with the drive unit in the center position;
[0045] FIG. 6 shows the pneumatic spring percussion mechanism of FIG. 4 with the drive unit in the extreme front position;
[0046] FIG. 7 shows a schematic view of a section through a percussion mechanism according to a third specific embodiment of the present invention; and
[0047] FIG. 8 shows a schematic representation of a section through a percussion mechanism according to a fourth specific embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0048] FIGS. 1 to 3 and 4 to 6 show two different specific embodiments of the percussion mechanism according to the present invention, realized as a pneumatic spring percussion mechanism, in a highly simplified schematic representation. In particular, known components such as electrical terminals and sensors are omitted because they do not relate to the present invention. The percussion mechanism according to the present invention can be used particularly advantageously in a drilling and/or striking hammer. Here, various types of percussion mechanism can be realized, of which in particular pneumatic spring percussion mechanisms are particularly suitable.
[0049] FIGS. 1 to 3 show a first specific embodiment of the present invention having a pneumatic spring percussion mechanism driven by an electrodynamic linear drive. Here, a drive unit (explained in more detail below) is shown in the representation in FIG. 1 in an extreme upper/rear position; in FIG. 2 is shown in a center position and in FIG. 3 it is shown in an extreme lower/front position.
[0050] The pneumatic spring percussion mechanism has a drive piston 1 that surrounds a piston head 2 of a percussion piston 3 . A shaft 4 of percussion piston 3 extends through a front side of drive piston 1 into a percussion piston guide 5 , and in its frontmost position can strike a tool end 6 , as is shown in FIG. 3 . Instead of tool end 6 , in a known manner an intermediate header can also be provided.
[0051] Between drive piston 1 and percussion piston 3 there is formed a first hollow space 7 , in which a main pneumatic spring 8 acts. When there is a forward movement of drive piston 1 , which is capable of axial back-and-forth movement in a percussion mechanism housing 9 , a pressure builds up in main pneumatic spring 8 that drives percussion piston 3 forward, so that it can finally strike against tool end 6 .
[0052] When there is a return movement of drive piston 1 , a partial vacuum arises in main pneumatic spring 8 that suctions back percussion piston 3 with its piston head 2 . The return movement of percussion piston 3 is also supported by the impact reaction at tool end 6 . In addition, seen in the direction of impact, in front of piston head 2 a return pneumatic spring 10 is formed in another hollow space, and this return spring acts during the return movement of drive piston 1 . It also supports the return movement of percussion piston 3 .
[0053] In order to compensate air losses in pneumatic springs 8 , 10 , a plurality of air compensation pockets 11 are provided on the inner wall of drive piston 1 . Their functioning is known from the prior art, so that a more detailed description is not necessary here. Instead of air compensation pockets 11 , other air ducts are also known that enable ventilation of pneumatic springs 8 , 10 in order to enable the compensation of air losses caused by compression.
[0054] The oscillating linear back-and-forth movement of drive piston 1 is brought about by an electrodynamic linear drive. For this purpose, drive piston 1 is coupled to a runner 12 of the linear drive. Runner 12 can be formed by a plurality of electrical sheets layered one over the other, and is moved back and forth by alternating magnetic fields produced by a stator 13 of the linear drive. The functioning of such a linear drive is known and is described for example in DE 102 04 861 A1. The linear motor can be for example a reluctance motor having an externally situated stator.
[0055] Runner 12 and drive piston 1 than a one-piece drive unit.
[0056] In front of drive piston 1 , an additional, second hollow space 14 is formed between drive piston 1 and percussion mechanism housing 9 ; in the positions shown in FIGS. 1 and 2 , this hollow space 14 is connected to the surrounding environment via ventilation openings 15 .
[0057] In the position of the drive unit shown in FIG. 3 , runner 12 has moved drive piston 1 forward far enough that drive piston 1 has moved past ventilation openings 15 . This causes ventilation openings 15 to be sealed, so that second hollow space 14 is separated from the surrounding environment. Correspondingly, an air spring forms in second hollow space 14 that acts against drive piston 1 and brakes its movement in the forward or impact direction.
[0058] So that the pneumatic spring can be produced in second hollow space 14 in a suitable manner, and in particular does not act against percussion piston 3 , which is supposed to strike tool end 6 in as unhindered a manner as possible, drive piston 1 forms a piston surface 16 at its front side. Piston surface 16 compresses the pneumatic spring in second hollow space 14 .
[0059] Depending on the dimensioning, it is possible for stator 13 to be switched currentless at the time at which ventilation opening 15 is closed by drive piston 1 . The braking of the drive unit made up of drive piston 1 and runner 12 then takes place exclusively through the pneumatic spring in second hollow space 14 . Because the compressed pneumatic spring then has a tendency to decompress, it additionally presses the drive unit back against the direction of impact. Then, as needed, stator 13 can again be excited in order to support the return movement.
[0060] The air spring in second hollow space 14 should be positioned or dimensioned in such a way that the drive unit is caught at the lower reverse point before percussion piston 3 strikes tool end 6 .
[0061] Corresponding to the air spring in second hollow space 14 , on the opposite side, behind drive piston 1 or behind the overall drive unit, there is formed a third hollow space 17 between drive piston 1 , or the drive unit, and percussion mechanism housing 9 . Percussion mechanism housing 9 is however shown only schematically in the Figures. Of course, percussion mechanism housing 9 can be assembled from various components, or can have a construction differing from that shown in the Figures.
[0062] In the positions shown in FIGS. 2 and 3 , third hollow space 17 stands in communicating connection to the surrounding environment via ventilation openings 18 .
[0063] In contrast, in the position shown in FIG. 1 the drive unit has, passed over ventilation openings 18 and thus closed them. Correspondingly, third hollow space 17 is separated from the surrounding environment, so that an air spring can build up in this hollow space, as is shown in particular in FIG. 1 . This air spring brakes the movement of the drive unit during its return stroke. Depending on the dimensioning, the air spring in third hollow space 17 can be strong enough to completely brake the return stroke and to convert it into a counter-movement, namely a movement in the impact direction. Here as well, stator 13 , in a manner similar to the functioning of the air spring in second hollow space 14 , can be switched off, or switched on only as needed.
[0064] The air spring in third hollow space 17 should be made as long as possible so that it is compressed over a longer movement path of the drive unit. During the return stroke of the drive unit, in comparison to the impact stroke, relatively little energy is required, which can then be stored in the air spring in third hollow space 17 . The stored energy is subsequently available during the forward movement of drive piston 1 in order to move this piston against percussion piston 3 . The energy stored in the air spring of third hollow space 17 thus supports the linear drive, which can then either correspondingly be dimensioned more weakly, or together with which a significantly higher impact energy can be achieved.
[0065] FIGS. 4 to 6 show a second specific embodiment of the present invention which differs from the first specific embodiment shown in FIGS. 1 to 3 with respect to the construction of the electrodynamic linear drive. Identical components are designated by identical reference characters. FIG. 4 shows the drive unit in an extreme upper/rear position, FIG. 5 shows it in a center position, and FIG. 6 shows it in an extreme lower/front position.
[0066] Such a linear drive can be realized for example by a magnetic motor.
[0067] Drive piston 1 has a runner 19 in the form of two sword-shaped or disk-shaped extensions 20 . Rare earth magnets 21 are fastened to extensions 20 , and these magnets can each be moved back and forth in a stator 22 .
[0068] Alternatively, in another specific embodiment (not shown) of the present invention, runner 19 can be provided with an annular extension that can be moved in an annular stator.
[0069] Behind drive piston 1 , in cooperation with percussion mechanism housing 9 a third hollow space 23 is formed in which an air spring can be produced. As explained above, the concept “percussion mechanism housing” 9 is to be understood broadly. What is important is that in cooperation with drive piston 1 or the drive unit made up of drive piston 1 and runner 19 , a hollow space can be produced in which an air spring can form.
[0070] In runner 19 , a ventilation opening 24 is formed that, in the position shown in FIG. 5 , covers a ventilation opening 25 present in percussion mechanism housing 9 , so that air can flow from the surrounding environment into third hollow space 23 , in order to restore the air previously lost during the compression of the air spring. In the positions shown in FIGS. 4 and 6 , ventilation openings 24 and 25 are not positioned one over the other, so that third hollow space 23 is separated from the surrounding environment.
[0071] The cooperation of drive piston 1 and percussion piston 3 , as well as the functioning of second hollow space 14 , corresponds to the first specific embodiment, so that the description thereof is not repeated here.
[0072] FIG. 7 shows a schematic section through a third specific embodiment of the present invention. In contrast to the pneumatic spring percussion mechanisms described above on the basis of FIGS. 1 to 6 , the third specific embodiment according to FIG. 7 relates to a percussion mechanism in which the energy for the percussion movement cannot be transmitted by an air spring. Correspondingly, this percussion mechanism cannot be designated a pneumatic spring percussion mechanism.
[0073] The percussion mechanism is driven by an electrodynamic linear drive, in a manner similar to the above-described pneumatic spring percussion mechanisms. It has a drive unit 30 that combines the functions of a drive element and a runner of the linear drive. Drive unit 30 is shown only schematically in FIG. 7 . Thus, for example the construction of the runner is not shown in detail. However, the details described above relating to runner 12 ( FIG. 1 ) or runner 19 ( FIG. 4 ) hold here as well.
[0074] Analogously to the above description, drive unit 30 is capable of being moved back and forth in a tube-shaped percussion mechanism housing 9 , the movement being brought about by stator 13 .
[0075] Drive unit 30 has a sleeve-shaped construction, and has in its interior a hollow area in which percussion piston 3 , which forms a percussion element, is capable of being moved back and forth. Percussion piston 3 then strikes the tool (not shown in FIG. 7 ) in a known manner.
[0076] In order to transfer the movement of drive unit 3 to percussion piston 3 , a coupling device is provided. The coupling device has a catch 31 , carried by percussion piston 3 , in particular by piston head 2 of percussion piston 3 , that can be moved back and forth in recesses of drive unit 30 in the working direction of the percussion mechanism. Catch 31 can for example be formed by a cross-bolt that passes through piston head 2 of percussion piston 3 , as is shown in FIG. 7 .
[0077] The recesses in drive unit 30 are formed by two longitudinal grooves 32 that extend axially and that pass through the wall of hollow cylindrical drive unit 30 .
[0078] On the front sides of longitudinal grooves 32 , lower stops 33 and upper stops 34 are formed that limit the longitudinal motion of catch 31 in longitudinal grooves 32 .
[0079] When there is a back-and-forth movement of drive unit 30 , percussion piston 3 is thus coercively guided by the respective stops 33 , 34 , as well as by catch 31 . Given a forward movement of drive unit 30 (downward in FIG. 7 ) in the direction of the tool (working direction), upper stops 34 press catch 31 with percussion piston 3 downward, such that percussion piston 3 should be able to fly free shortly before contacting the tool or the intermediately situated header, in order to avoid damaging effects on drive unit 30 and catch 31 . In the subsequent return movement of drive unit 30 , lower stops 33 come into contact with catch 31 and draw back percussion piston 3 , which is also driven back by the tool, in the direction opposite the working direction. The working cycle then repeats in that drive unit 30 , with upper stops 34 , again accelerates percussion piston 3 against the tool.
[0080] In this specific embodiment, the coupling device is thus not formed by an air spring, but rather by longitudinal grooves 32 , stops 33 , 34 , and catch 31 . Of course, the described design serves only for explanation. Numerous other possibilities will be recognized by those skilled in the art for the transfer of the movement of drive unit 30 to percussion piston 3 .
[0081] FIG. 8 shows, in a schematic representation, a section through a percussion mechanism according to a fourth specific embodiment of the present invention.
[0082] Here, the basic design of the percussion mechanism is identical to that of the percussion mechanism according to FIG. 7 . In addition, piston head 2 of percussion piston 3 is coupled with a positive fit to a reversing piston 36 via a piston rod 35 . Reversing piston 36 is capable of being moved back and forth in a reversing cylinder 37 , which is for example part of percussion mechanism housing 9 , in a manner corresponding to the movement of percussion piston 3 .
[0083] Reversing piston 36 and reversing cylinder 37 enclose a reversing hollow space 38 in which a reversing air spring 39 is formed.
[0084] Similar to the manner in which, in the first specific embodiment shown in FIGS. 1 to 3 , the reversing air spring in reversing hollow space 17 brakes a return movement of drive piston 1 depicted there, and later supports a forward movement, the reversing air spring 39 shown in FIG. 7 is tensioned when there is a return movement of percussion piston 3 , so that this air spring can subsequently support a forward movement of percussion piston 3 .
[0085] The compensation of air losses of reversing air spring 39 takes place in a manner similar to that in the above-described specific embodiments, so that a detailed description can be omitted here.
[0086] For reversing air spring 39 as well, it can be particularly useful if it is charged over a longer movement path of percussion piston 3 . In the fourth specific embodiment shown in FIG. 8 , the compressing of reversing air spring 39 takes place in a particularly reliable fashion, because the entrained movement of percussion piston 3 is achieved through the positive coupling, brought about by the coupling device, between drive unit 30 and percussion piston 3 .
[0087] The present invention makes it possible to increase the degree of efficiency of a linearly driven electrodynamic percussion mechanism. Through the intermediate storage of energy in the air springs, a more uniform electrical power consumption with low load peaks can be achieved. Moreover, impact-type loads on the hammer housing at the reverse points of the drive unit are avoided. The percussion mechanism according to the present invention can achieve greater demolition performance with a simultaneous reduction in hand-arm vibrations. | A percussive mechanism, which is provided in the form of an, e.g. pneumatic spring percussive mechanism, comprises an electrodynamic linear drive, a drive piston, which can be reciprocally moved inside a percussive mechanism housing by the linear drive, and a percussive piston. An additional hollow space is provided in front of and/or behind the drive piston and can be isolated at least in part from the surrounding area so that a pneumatic spring can be created in the additional hollow space. The pneumatic spring slows the drive piston at its returning points and facilitates a returning motion without loading the electrodynamic linear drive. | 1 |
RELATED APPLICATIONS
[0001] This Patent application is a continuation-in-part of U.S. patent application Ser. No. 11/070,411 filed on Mar. 1, 2005 and entitled Apparatus, System, and Method for Directional Degradation of a Paved Surface, which is herein incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to road resurfacing equipment and more particularly to apparatus, systems and methods for recycling a paved surface in situ.
[0004] 2. Background
[0005] Asphalt is the most recycled material in the United States. In fact, more than 73 million tons of asphalt pavement removed each year during highway widening and resurfacing projects is reused as pavement. Such recycling efforts conserve natural resources, decrease construction time, minimize the impact of asphalt plant operations on the environment, and reduce reliance on landfills. Further, research shows that the structural performance of mixtures integrating reclaimed asphalt pavement (“RAP”) is equal to, and in some instances better than, virgin asphalt pavement.
[0006] A process for recycling a paved surface may include mechanically breaking up a paved surface, applying fresh asphalt or asphalt rejuvenation materials to the broken pieces, depositing the mixture over the road surface, and compacting the mixture to restore a smooth paved surface. In some cases, broken asphalt may be removed from a road surface, treated off location, and then returned and compacted. By enabling the majority of road surface excavation and renovation to occur through a continuous operation in situ, road recycling processes reduce manpower, time and resources required with conventional road resurfacing techniques.
[0007] In some cases, a paved surface may be pre-heated to facilitate pavement removal as well as to increase thermal bonding between new and reclaimed pavement constituents. The low heat conductivity of asphalt and its susceptibility to damage from scorching or overheating, however, creates a dilemma in pavement recycling. In some cases, intense heat must be applied to bring the full depth of the pavement to a workable temperature while the pavement surface must be protected from scorching or overheating.
[0008] To overcome this problem, many conventional road recycling processes require heating equipment to make several passes over the same section of roadway in order to heat and work the pavement to a sufficient depth. This procedure is inefficient, time-consuming, and results in most of the heat being concentrated at the pavement surface, as opposed to a uniform distribution through the full depth of the paved surface. Other road recycling processes use multiple heating units that each operate at a temperature below the asphalt burning point. A large number of such units are required to achieve the desired heat penetration, thereby increasing the amount and cost of recycling equipment needed to repair a paved surface
[0009] Accordingly, what are needed are improved apparatus, systems, and methods for in situ pavement recycling. More particularly, apparatus, systems, and methods are needed allowing application of higher temperatures to a paved surface in situ, while providing more uniform heat distribution and a reduced likelihood of burning, scorching, or other damage. Beneficially, such a system would improve the bond between new and recycled pavement constituents, reduce the amount of new pavement materials needed to rejuvenate a paved surface, facilitate immediate pavement finishing processes, and increase the structural integrity of the resulting recycled paved surface. Such apparatus, systems, and methods are disclosed and claimed herein.
SUMMARY OF THE INVENTION
[0010] Consistent with the foregoing, and in accordance with the invention as embodied and broadly described herein, a system for recycling pavement constituents in situ is disclosed. A vehicle for traversing the pavement constituents has a container for storing heated pavement rejuvenation materials and there is at least one heating element adapted to heat the pavement rejuvenation materials within the container. A dispensing element is in communication with the container for dispensing the pavement rejuvenation materials to the pavement constituents on a road bed. The vehicle also supports at least one mixing element which is adapted to mix in situ the pavement constituents and the heated pavement rejuvenation materials together in such a manner that the pavement constituents are raised to a working temperature. The system also comprises a compacting element for compacting the resulting mixture of pavement constituents and pavement rejuvenation materials into a new road surface.
[0011] In certain aspects of the present invention the at least one mixing element rotates on an axis normal to a road bed. The mixing element may be further adapted for independent movement to avoid obstacles on the road bed, such as manholes, tracks, utilities, and curbs. The mixing element may be adapted to move independently of other mixing elements also supported by the vehicle in a vertical direction, horizontal direction, circular direction, and/or an angular direction. The mixing element may be supported by the vehicle in a reducing environment, which is adapted to prevent oxidation of the pavement constituents and/or the pavement rejuvenation materials. The reducing environment may further comprise a reduction source selected from the group consisting of an exhaust gas, a rich-burning flame, or a reducing gas. Mixing elements may be selected from the group consisting of mills, degradation elements, screeds, rakes, tongs, or drums.
[0012] The dispensing element may be formed in the mixing element. At least a second dispensing element may be in communication with a supply selected from the group consisting of water, polymers, surfactant, and combinations thereof. The second dispensing element may be adapted to dispense the supply into the pavement constituents.
[0013] The vehicle may also support at least one degradation element adapted to degrade a paved surface into pavement constituents. The at least one degradation element may be spaced within a predetermined distance from the mixing element wherein the predetermined distance controls the maximum size of the pavement constituents.
[0014] The container on the vehicle may be adapted to store the heated pavement rejuvenated materials in a reducing environment. The heating elements adapted to heat the pavement rejuvenation materials may be selected from the group consisting of radiant heaters, hot air heaters, convection heaters, microwave heaters, direct flame heaters, and combinations thereof. The vehicle may also support at least another heating element, which may be selected from the same group, to aid in heating the pavement constituents to a working temperature. The working temperature may be between 200° F. to 1100° F., an ideal working temperature may depend on the type and size of the pavement constituents as well as other factures like climate.
[0015] In another aspect of the present invention a method includes recycling pavement in situ. The method comprises the steps of degrading a paved surface to produce pavement constituents; heating the constituents to a working temperature by simultaneously dispensing heated pavement rejuvenation materials and mixing the pavement constituents with the heated pavement rejuvenation material; and compacting the resulting mixture of pavement constituents and pavement rejuvenation materials into a new road surface.
[0016] The mixing may be accomplished by a plurality of mixing elements adapted to rotate on an axis normal to a road bed. The maximum constituents size may be controlled by the distance between the plurality of mixing element and a plurality of degradation elements. The heated pavement rejuvenation materials may be stored in a reducing environment before they are dispensed and mixed with the pavement constituents. The heating may be performed in a reducing environment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order that the manner in which the above recited and other features and advantages of the present invention are obtained, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which are illustrated in the appended drawings. Understanding that the drawings depict only typical embodiments of the present invention and are not, therefore, to be considered as limiting the scope of the invention, the present invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:
[0018] FIG. 1 is a perspective view of one embodiment of an apparatus for recycling pavement in situ in accordance with the present invention;
[0019] FIG. 2 is a perspective view of one embodiment of an apparatus for recycling pavement in situ, with the outer shroud removed;
[0020] FIG. 3 is a side view of one embodiment an assembly comprising a mixing and heating mechanism in accordance with the invention;
[0021] FIG. 4 is a side view of another embodiment of an assembly comprising a mixing and heating mechanism in accordance with the invention;
[0022] FIG. 5 is a side view of another embodiment of an apparatus for recycling pavement in situ;
[0023] FIG. 6 is a perspective view of an embodiment of a plurality of mixing elements;
[0024] FIG. 7 is a bottom view of an embodiment of degradation and mixing elements;
[0025] FIG. 8 is a bottom perspective view of another embodiment of an apparatus for mixing and heating pavement materials in situ;
[0026] FIG. 9 is a side perspective view of the mixing and heating mechanisms illustrated with the apparatus of FIG. 5 ;
[0027] FIG. 10 is a side perspective view of one embodiment of an apparatus comprising a reduction chamber surrounding the heating and mixing elements;
[0028] FIG. 11 is a perspective view illustrating mixing elements that may be elevated to avoid obstacles in the roadway;
[0029] FIGS. 12 through 18 illustrate various embodiments of mixing elements in accordance with the invention; and
[0030] FIG. 19 is a flow diagram of one embodiment of a process for recycling a paved surface in situ.
DETAILED DESCRIPTION OF THE INVENTION
[0031] Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment in accordance with the present invention. Thus, use of the phrase “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but does not necessarily, all refer to the same embodiment.
[0032] Furthermore, the present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.
[0033] In the following description, numerous specific details are disclosed to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention.
[0034] In this application, “pavement” or a “paved surface” refers to any artificial, wear-resistant surface that facilitates vehicular, pedestrian, or other form of traffic. Pavement may include composites containing oil, tar, tarmac, macadam, tarmacadam, asphalt, asphaltum, pitch, bitumen, minerals, rocks, pebbles, gravel, sand, polyester fibers, Portland cement, petrochemical binders, or the like. The term “degrade” is used in this application to mean milling, grinding, cutting, ripping apart, tearing apart, or otherwise taking or pulling apart a pavement material into smaller constituent pieces. Similarly, the term “pavement constituents” is used to mean any materials or components used to create a paved surface, including new or reclaimed materials, or combinations thereof.
[0035] Referring to FIG. 1 , one contemplated embodiment of an apparatus 100 for use in pavement recycling applications is illustrated. In general, an apparatus 100 may include a frame 102 , a shroud 104 or cover 104 enclosing various internal component of the apparatus 100 , and a translation mechanism 106 , such as tracks, wheels, or the like, to translate the apparatus 100 along a surface. The translation mechanism 106 may include several sets of tracks, for example, which may be vertically adjusted with respect to the frame 102 to adjust the slant or elevation of the apparatus 100 , and to adjust for varying elevations, slopes, and contours of the underlying road surface.
[0036] The apparatus 100 may include one or more heating and mixing assemblies 108 a , 108 b as will be described with additional specificity with respect to FIGS. 3 and 4 , which may be used to simultaneously heat and mix pavement constituents 105 for compaction into a new or recycled road surface 109 . In selected embodiments, a first heating and mixing assembly 108 a may be extended and retracted with respect to one side of the apparatus 100 and a second heating and mixing assembly 108 b may be extended and retracted with respect to a second side of the apparatus 100 , thereby allowing the heating and mixing assemblies 108 a , 108 b to sweep over an area significantly wider than the apparatus 100 . In selected embodiments, the width of each heating and mixing assembly 108 a , 108 b may approximate the width of the apparatus 100 . In such embodiments, the assemblies 108 a , 108 b may sweep over a road width that is approximately twice the apparatus width when the assemblies 108 a , 108 b are fully extended from each side of the apparatus 100 . The extension and retraction of the assemblies 108 a , 108 b will become more readily apparent from the description of FIG. 5 .
[0037] As will become more apparent from the description of FIGS. 3 and 4 , the heating and mixing assemblies 108 a , 108 b may include a variety of elements to process and manipulate the pavement constituents 105 . For example, these elements may include mixing elements to mix the pavement constituents 105 , heating mechanisms to apply heat to the pavement constituents 105 as they are mixed by the mixing elements, and dispensing elements to dispense a supply of water, surfactant, polymers, and/or new pavement materials to mix with the pavement constituents 105 extracted from the road surface 107 . In selected embodiments, the heating and mixing assemblies 108 a , 108 b may optionally include degradation elements to degrade an existing paved surface 107 into smaller fragments or constituent pieces 105 . One of ordinary skill in the art will recognize, however, that in other embodiments, the heating and mixing assemblies 108 a , 108 b may be used to process and manipulate pavement fragments or constituents 105 previously generated by other road reconstruction equipment. In such embodiments, the apparatus 100 may not include degradation elements.
[0038] The apparatus 100 may include one or more compaction elements 110 a , 110 b , such as rollers, screeds, or tampers. These compaction elements 110 a , 110 b may be used to compact and smooth the mixture of pavement constituents 105 produced by the mixing and heating assemblies 108 a , 108 b . Like the heating and mixing assemblies 108 a , 108 b , the compaction elements 110 a , 110 b may be extended and retracted with respect to each side of the apparatus 100 to allow the compaction elements 110 a , 110 b to compact or smooth a surface wider than the apparatus 100 . In selected embodiments, the compaction elements 110 a , 110 b may be extended and retracted to reflect the position of the heating and mixing assemblies 108 a , 108 b . Both the heating and mixing assemblies 108 a , 108 b and the compaction elements 110 a , 110 b may include extension and retraction mechanisms 112 such as tracks, hydraulic or pneumatic cylinders, or other mechanisms known to those skilled in the art, to extend and retract the assemblies 108 a , 108 b and the compaction elements 110 a , 110 b with respect to the apparatus 100 . In some embodiments, the compaction element may also be heated.
[0039] Referring to FIG. 2 , under the shroud 104 , the apparatus 100 may include a variety of components to perform various features and functions. For example, in certain embodiments, the apparatus 100 may include an engine 114 , such as a diesel or gasoline engine, to power the apparatus 100 . The engine 114 may receive fuel from a fuel tank 116 . In certain embodiments, the engine 114 may be used to drive one or more hydraulic pumps 118 which may drive hydraulic motors (not shown) for powering the translation mechanism 106 . The hydraulic pumps 118 may also be used to drive one or more hydraulic cylinders 120 , connected to the translation mechanism 106 , for adjusting the level, slant, or elevation of the apparatus 100 , or to compensate for variations in elevation and slope of the underlying road surface. The hydraulic pumps 118 may also be used to power the extension and retraction mechanisms 112 connected to the heating and mixing assemblies 108 a , 108 b and the compaction elements 110 a , 110 b . Additionally, the hydraulic pumps 118 may be used to power the mixing, dispensing, and degradation elements, as will be described with respect to FIGS. 3 and 4 .
[0040] In selected embodiments, the apparatus 100 may include an air compressor 122 to provide pneumatic power or an air supply to the apparatus 100 . Similarly, the apparatus 100 may include one or more tanks 124 to store hydraulic fluid and additional hydraulic pumps 126 which may be used to supplement the hydraulic pumps 118 powered by the engine 114 . In certain embodiments, the apparatus 100 may include a computer or other electronic equipment 128 to control the apparatus 100 , and to communicate with various remote sources, including but not limited to radio, satellite, cellular, Internet, or other sources. In selected embodiments, the computer and electronic equipment 128 may communicate wirelessly with these remote sources by way of one or more antennas 130 . Such a system may permit the apparatus 100 to be controlled or monitored remotely, or allow data to be uploaded or downloaded to the apparatus 100 , as needed. The apparatus 100 may also take advantage of various control systems used in modern asphalt mills, grinders, and cutters, to provide manual or automated control of the apparatus 100 , including but not limited to elevation, speed, steering, cut depth, and leveling controls. These controls may employ various feedback systems and sensors located at a variety of locations around the apparatus 100 .
[0041] The apparatus 100 may also include at least one container such as a hopper 132 and/or a tank 134 . The containers may store rejuvenation or renewal materials that may be mixed with pavement constituents on the road bed 107 . The resulting mixture may then be applied to the road bed to create a recycled surface 109 . Rejuvenation or renewal materials that may be stored in the hopper 132 , tank 134 , or both, to be used in a recycling process may include, for example, oil, tar, tarmac, macadam, tarmacadam, asphalt, asphaltum, pitch, bitumen, minerals, rocks, pebbles, gravel, sand, polyester fibers, Portland cement, petrochemical binders. Electronic 241 may control a heating element internal to the tank 134 and/or hopper 132 for heating the pavement rejuvenation material. In some embodiments a surfactant may be added with the rejuvenation or renewal materials. It is believed that the surfactant may help reduce the surface tension of oils and help promote mixing. Other rejuvenation materials or renewal materials may foam, which may also aid in pavement recycling process. In selected embodiments, the hopper 132 may be used to store dry materials, such as rocks and gravel, and the tank 134 may be used to store liquids, such as oil or tar.
[0042] Referring to FIG. 3 , one contemplated embodiment of a heating and mixing assembly 108 is illustrated. Various details, such as the extension and retraction mechanisms 112 illustrated in FIGS. 1 and 2 , have been omitted in this example for sake of simplicity. As illustrated, a heating and mixing assembly 108 in accordance with the invention may include a heating mechanism 136 and one or more mixing elements 138 a - c . The heating mechanism 136 may be positioned substantially above or adjacent to the mixing elements 138 a - c in order to apply heat to the pavement constituents 105 as they are mixed by the mixing elements 138 a - c . By heating and mixing the pavement constituents 105 simultaneously, much higher temperatures may be applied to the to pavement constituents 105 without burning, damaging, or destroying asphalt, tar, oil, or other heat-sensitive materials in the pavement. This is because the mixing elements 138 a - c circulate the pavement constituents such that high temperatures are not directly concentrated on any specific portion of the pavement constituents 105 for more than a brief period of time. As a result, the pavement constituents 105 may be heated more rapidly and uniformly.
[0043] The mixing elements 138 a - c may be adapted to circulate the pavement constituents 105 vertically, horizontally, or a combination thereof, with respect to the road surface. For example, selected mixing elements 138 a , 138 b may be adapted to vertically circulate the pavement constituents between the underlying road bed and the surface. In this example, the helical vanes of the mixing elements 138 a , 138 b may be used to circulate the pavement constituents in a substantially vertical direction. In other embodiments, a mixing element 138 c may be used to circulate pavement constituents 105 in a substantially horizontal direction. Here, the curved shaped of the mixing element 138 c may be used to stir the pavement constituents 105 primarily in the horizontal plane parallel to the road surface. By mixing the pavement constituents 105 both vertically and horizontally, the mixing elements 138 a - c disperse the heat uniformly through the pavement constituents 105 , thereby preventing burning, scorching, or damage thereto.
[0044] As mentioned, the ability to apply higher temperatures to the pavement constituents 105 allows more rapid heating of the pavement constituents 105 and allows use of higher temperature heating mechanisms 136 . In this example, the heating mechanism 136 is a tubular radiant heater. Nevertheless, any suitable heater may be used to heat the pavement constituents 105 while mixing, including but not limited to a hot air heater, a convection heater, a microwave heater, or a direct flame heater. Although not illustrated in this example, the heating mechanism 136 may also incorporate a blower, or vents, to more effectively direct the heat toward the pavement constituents 105 .
[0045] The preferred heating mechanism may also comprise the hot pavement rejuvenation material. In this embodiment the pavement rejuvenation material may be preheated before it is dispensed onto the road bed, which may be done in a reducing environment. It is believed that if the hot pavement rejuvenation material is heated to 2000° F. (this may be accomplished in the reducing environment without combustion in either the tank 132 or hopper 134 ) and then is added to the road bed to constitute 10 percent of the aggregate and the pavement constituents are about 50° F. and constitutes 90 percent of the aggregate then the overall temperature of the mixed aggregate will be about 245° F. One of ordinary skill in the art would recognize how to adjust the temperatures and ratios to achieve their desired temperature. It is believed that for an embodiment as described in this paragraph, an ideal temperature would be within a range of 200° F. to 400° F.
[0046] Mixing also allows higher temperatures since the heat will not be focused on just pavement constituents closest to the heating mechanism, but the heat will be more evenly distributed throughout all of the pavement constituents and the pavement rejuvenation materials.
[0047] The heating and mixing assembly 108 may also include a dispensing element 140 to provide a supply of new pavement materials 142 , such as rocks, gravel, or sand to mix with the pavement constituents 105 extracted from the existing road surface 107 . In selected embodiments, a mixing element 138 c may also function as a dispensing element. For example, a mixing element 138 c may include a central bore 144 for dispensing a material 146 such as oil, tar, asphalt, or the like for mixing with the pavement constituents 105 . The dispensing elements 140 , 138 c may communicate with a remote supply of new pavement materials, such as those stored in the hopper 132 or tank 134 as discussed with respect to FIG. 2 . In selected embodiments, new pavement materials 142 , 146 provided by the dispensing elements 140 , 138 c may be pre-heated prior to addition to the existing constituents 105 . This may aid in heating the resulting mixture and may provide improved bonding. Once the newer materials 142 , 146 are mixed with those extracted from the road surface 107 , the resulting mixture may be compacted into a new or recycled surface 109 by the compaction element 110 . In other embodiments, as shown in FIG. 5 , the dispensing element 140 is attached to the vehicle and directs the new pavement materials 142 , water, surfactant, and/or polymers to the degradations element 147 and/or the mixing element.
[0048] As mentioned, in selected embodiments the heating and mixing assembly 108 may include degradation elements 147 to degrade the paved surface 107 . One type of degradation element 147 that may be suitable for use with the present invention is described in U.S. patent application Ser. No. 11/070,411 and entitled “Apparatus, System, and Method for Directional Degradation of a Paved Surface,” having common inventors with the present invention, to which this application claims priority and incorporates by reference in its entirety. In this example, the degradation element 147 rotates about an axis substantially normal to the road surface. As the apparatus 100 moves forward, the degradation element 147 cuts or tears into the paved surface 107 using a motion similar to that of a router bit cutting into a wood surface. Nevertheless, one of ordinary skill in the art will recognize that the heating and mixing elements 136 , 138 a - c may function with other types of road cutting and milling equipment, including convention cutting drums rotating about an axis substantially parallel to the road surface. Thus, any type of cutting, milling, or degrading element 147 is within the scope of the present invention.
[0049] In certain embodiments, a skirt 149 may be used to surround the heating and mixing elements 136 , 138 a - c , thereby creating a high-temperature or reduction chamber 151 . The skirt 149 may be used to retain and focus the heat produced by the heating mechanism 136 on the pavement constituents 105 , in addition to reducing dust or other particulates produced from the heating and mixing process. In selected embodiments, an oxidation-depleted (i.e., reducing) gas may also be introduced inside the skirt 149 to reduce the oxidation of the pavement constituents 105 , thereby promoting improved bonding between the new pavement materials 142 , 146 and materials recycled from the road surface 107 . This concept will be described in additional detail in the description associated with FIG. 7 .
[0050] Referring to FIG. 4 , in another contemplated embodiment in accordance with the invention, a heating and mixing assembly 108 may include heating mechanisms 136 a - b , such as a microwave heater 136 a , a radiant heater 136 b , or the like. A first mixing element 138 a may be effective to circulate the pavement constituents 105 substantially vertically while a second mixing element 138 c may be effective to stir the pavement constituents 105 substantially horizontally with respect to the paved surface. The second mixing element 138 c may also include a central bore 144 for dispensing a supply of pavement rejuvenation materials 146 , such as tar, oil, or asphaltum. This mixing element 138 c may reach a depth sufficient to deposit the rejuvenation materials 146 at or near the road bed 148 to promote thorough mixing with the pavement constituents 105 and effective bonding between the recycled surface and the underlying road bed 148 . Another dispensing element 140 may be used to supply a quantity of new pavement materials 142 , such as rock, gravel, sand to the mixture 105 .
[0051] Referring to FIG. 5 , another embodiment of the present invention is shown. A dispensing element 240 directs pavement rejuvenated material 142 to the degradation elements 147 . The rejuvenated materials 142 are mixed immediately into the pavement constituents 105 as the degradation elements 147 degrade the paved surface 107 . It is believed that such an embodiment effectively wets at least a majority of the pavement constituent's surface areas. Another dispensing element 140 adds hot pavement constituents to the pavement constituents 105 already residing in the road bed. A plurality of mixing elements 138 follow the degradation elements 147 , allowing the heat from the added pavement constituents and pavement rejuvenated materials to be spread evenly throughout the aggregate.
[0052] FIG. 6 shows an embodiment of a plurality of mixing elements 138 shown detached from the vehicle for clarity. Each mixing element 138 comprises a shaft 201 with a dispensing port 200 located through its center. The dispensing ports 200 , may also add rejuvenated materials or new pavement constituents. It may be desirable to dispense hot oil or other pavement rejuvenated materials from the dispensing ports 200 directly on the road bed to promote bonding between the road bed and the pavement constituents 105 .
[0053] FIG. 7 shows an embodiment of the degradation element 147 and a plurality of mixing elements 138 . In some embodiments of the present invention, the degradation elements 147 are separated by a predetermined distance 202 to control the maximum size a pavement constituent may be. It may be preferable to have the maximum constituent size be ½ inch; in such an embodiment, the degradation elements 147 may be spaced substantially ½ inch apart. Further the mixing element would also need to be spaced ½ apart to allow the maximum constituent size to the pass between them. In accordance with the same embodiment, it may also be desirable to have the mixing elements 138 spaced ½ inch from the degradation element 147 ; allowing pavement constituents larger than ½ inch to be forced back to the degradation elements 147 . The plurality of mixing elements 138 may be stationary, or that may move in a vertical direction, horizontal direction, circular direction, and/or angular direction with respect to the vehicle. It would be obvious to one of ordinary skill in the art to adjust the predetermined distance 202 to achieve a different constituent size. It would also be obvious to one of ordinary skill in the art to modify the cutting depth, the rpm and/or size of the degradation element 147 and/or mixing element 138 to achieve other maximum constituent sizes and/or the distribution of constituent sizes.
[0054] Referring to FIGS. 8 and 9 , another contemplated embodiment of an apparatus 100 , comprising heating and mixing assemblies 108 a , 108 b , is illustrated. In this embodiment, a first heating and mixing assembly 108 a may be extended with respect to a first side 156 of the apparatus 100 , and a second heating and mixing assembly 108 b may be extended with respect to a second side 158 of the apparatus 100 , thereby enabling the heating and mixing assemblies 108 a , 108 b to traverse a pavement area significantly wider than the apparatus 100 .
[0055] The heating and mixing assemblies 108 a , 108 b may include various mixing elements 138 d to circulate the pavement constituents 105 primarily horizontally with respect to the pavement surface. These mixing elements 138 d may include agitation members 150 to circulate the pavement constituents 105 substantially horizontally as the mixing elements 138 d rotate. Other mixing elements 138 e may circulate the pavement constituents primarily vertically with respect to the pavement surface. These mixing elements 138 e may, in certain embodiments, include spiral or helical agitation members 152 around the perimeter thereof to circulate the pavement constituents 105 substantially vertically as the mixing elements 138 e rotate. One of ordinary skill in the art will recognize that by adjusting the angle of the agitation members 150 , 152 , the mixing elements 138 d , 138 e may, in some cases, be adapted to circulate the pavement constituents 105 both horizontally and vertically with respect to the pavement surface. In certain embodiments, the mixing elements 138 d , 138 e may include a central bore 154 or other channel 154 for supplying rejuvenation materials to the pavement constituents 105 .
[0056] A radiant heater 136 may be mounted immediately above or proximate the mixing elements 138 d , 138 e to heat the pavement constituents 105 , including old and new pavement materials, as the mixing elements 138 d , 138 e circulate the pavement constituents 105 . A radiant heater 136 may, for example, comprise a tubular structure to circulate hot water, steam, or other heated gases or liquids. Once the pavement constituents 105 are heated, mixed, and rejuvenation materials are added, the resulting mixture may be compacted by compaction elements 110 a , 110 b , such as rollers, tampers or screeds. The compaction elements 110 a , 110 b , like the heating and mixing assemblies 108 a , 108 b , may be extended from each side 156 , 158 of the apparatus 100 to follow the heating and mixing assemblies 108 a , 108 b.
[0057] Referring to FIG. 10 , in selected embodiments, an apparatus 100 in accordance with the invention may include a skirt 149 to create a high-temperature or reduction chamber 151 . The skirt 149 may surround the heating and mixing elements 136 , 138 a - c and may aid in heating the pavement constituents 105 by retaining or focusing heat inside the skirt 149 . In selected embodiments, the skirt 149 may be in communication with an oxygen-depleted gas source 160 which may include, for example, an exhaust source such as a fuel-rich exhaust source, or a flame such as a fuel-rich flame. An oxygen-depleted gas may also be directed to the containers shown in FIG. 2 , in order to heat the pavement rejuvenation materials to higher temperatures than would otherwise be allowed.
[0058] Still referring to FIG. 10 , in certain embodiments, exhaust 160 produced by the apparatus 100 may be directed into the chamber 151 to create an oxygen-depleted or reducing atmosphere. This atmosphere may aid in reducing the oxidation of pavement constituents 105 which may serve to create a stronger chemical bond between new and old pavement constituents 105 . The oxygen-depleted atmosphere may also reduce the likelihood of combustion or fire within the chamber 151 , which may, in turn, enable the application of significantly higher temperatures to the pavement constituents 105 . In other embodiments, gases directed into the chamber 151 may also aid in heating the pavement constituents 105 . Although illustrated as a fabric-like material, the skirt 149 may be also be embodied as a brush, bellow, or one or more metal or non-metal panels, as illustrated in FIGS. 1 and 2 .
[0059] As degradation elements 147 degrade a worn paved surface 107 , oxygen may bind to the surface of the pavement constituents 105 and interfere with pavement constituents 105 binding to other each other or to pavement rejuvenation materials 142 . It will be advantageous to mix the pavement constituents 105 within the reduction chamber 151 , so that all of the pavement constituent surfaces become exposed to the reducing environment within the reduction chamber 151 and become reduced.
[0060] Referring to FIG. 11 , in selected embodiments, mixing elements 138 d - e of a heating and mixing assembly 108 may be independently elevated with respect to the road bed 148 or surface 148 . Thus, the mixing elements 138 d - e may be elevated to avoid structures such as manholes 162 , culverts, or utility lines. For example, one or more mixing elements 138 d may be elevated to avoid a manhole 162 while others 138 e may be extended to mix the pavement constituents 105 . The mixing elements 138 d - e may be actuated by hydraulic, pneumatic, or other mechanical means known to those of skill in the art. Similarly, the elevation of the mixing elements 138 d - e may be controlled manually, such as by an operator, or automatically using sensors and/or feedback systems.
[0061] Referring generally to FIGS. 12 through 18 , various embodiments of mixing elements 138 for agitating or circulating the pavement constituents 105 are illustrated. Each of these embodiments may agitate, mix, blend, or circulate the pavement constituents 105 in a unique manner and direction, and each may be suitable for use in various different embodiments of the present invention. For example, referring to FIG. 12 , in certain embodiments a mixing element 138 may include a rotating shaft 164 comprising one or more agitation members 166 protruding therefrom. The shaft 164 may rotate about an axis substantially normal to the surface of the road. Likewise, the agitation members 166 may travel within a plane substantially parallel to the road surface, thereby circulating the pavement constituents substantially parallel to the road surface.
[0062] Referring to FIG. 13 , in another embodiment, a mixing element 138 may comprise a shaft 164 rotating about an axis substantially parallel to the road surface. In this embodiment, a rigid helix 168 or spiral 168 may be attached to the shaft 164 to circulate pavement constituents 105 in a direction substantially parallel to the shaft 164 . Thus, the pavement constituents 105 may circulate in a direction substantially parallel to the road surface. Alternatively, the shaft 164 might include agitation members 166 , like those illustrated with respect to FIG. 12 , which would circulate the pavement constituents 105 in a direction both perpendicular and parallel to the road surface. In certain embodiments, the shaft 164 may connect to and rotate with respect to one or more arms 170 extending from the apparatus 100 or heating and mixing assembly 108 .
[0063] Referring to FIG. 14 , in another contemplated embodiment, a mixing element 138 may include a shaft 164 and a helical member 172 attached thereto. The helical member 172 may optionally have a conical shape. As the shaft 164 rotates, the helical member 172 may circulate the pavement constituents 105 in direction both perpendicular and parallel to the road surface.
[0064] Referring to FIG. 15 , in another embodiment, a mixing element 138 may include one or more paddles 174 extending from a shaft 164 . The paddles 174 may be flat or curved to circulate the pavement constituents 105 as the shaft 164 rotates. By adjusting the curvature, pitch, or shape of the paddles 174 , the paddles 174 may be adapted to circulate the pavement constituents in a direction both perpendicular and parallel to the road surface. In certain embodiments, as illustrated by FIG. 13 , an opening 176 may be formed in the paddles 174 to improve or otherwise alter the mixing characteristics of the mixing element 138 .
[0065] Referring to FIG. 17 , in selected embodiments, a mixing element 138 may include one or more members 178 or paddles 178 that rotate about an axis substantially parallel to the road surface. Such an embodiment may be effective to mix or agitate the pavement constituents 105 in a direction both perpendicular and parallel to the road surface.
[0066] Referring to FIG. 18 , in yet another embodiment, a mixing element 138 may include a shaft 164 and a member 180 offset from the shaft 164 . Due to the offset, the member 180 may take a substantially circular path 182 as the shaft 164 rotates, thereby mixing and agitating the pavement constituents 105 .
[0067] Referring to FIG. 19 , a method for recycling a paved surface in situ in accordance with the present invention may include first degrading 186 a paved surface to produce degraded pavement constituents, heating and mixing 190 the degraded pavement constituents substantially simultaneously in situ to promote thermal bonding therebetween, and compacting 194 the degraded pavement constituents to provide a recycled paved surface. In some embodiments, a method in accordance with the present invention may further comprise pre-heating 184 the paved surface to soften the pavement prior to degradation.
[0068] A method for recycling a paved surface in situ may further comprise isolating 188 degraded pavement constituents in a reduction chamber during heating and mixing 190 , and adding 192 pavement renewal materials to the degraded pavement constituents to rejuvenate the pavement as needed. Finally, in some embodiments, a method in accordance with the present invention may include performing 196 finishing processes to finish the recycled paved surface. Finishing processes may include, for example, cleaning 198 the recycled paved surface, and/or marking 200 the recycled paved surface as appropriate.
[0069] The present invention may be embodied in other specific forms without departing from its essence or essential characteristics. The described embodiments are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the appended claims, rather than by the foregoing description. All changes within the meaning and range of equivalency of the claims are to be embraced within their scope. | The present invention includes a system for recycling pavement constituents in situ. A vehicle for traversing the pavement constituents comprising a container for storing and preserving heated pavement rejuvenation materials and at least one heating element adapted to heat the pavement rejuvenation materials above their working temperature. A dispensing element is in communication with the container for dispensing the pavement rejuvenation materials to the pavement constituents. The vehicle also supports at least one mixing element which is adapted to mix in situ the pavement constituents and the heated pavement rejuvenation materials together in such a manner that the pavement constituents are raised to a working temperature. The system also comprises a compaction element for compacting the pavement constituents. | 4 |
BACKGROUND
[0001] The invention relates to a security device for securing a jack plug during retail display of a product fitted with a jack plug.
[0002] One type of retail product that is fitted with a jack plug is a pair of headphones. During retail display of a pair of headphones, it is desirable to allow a potential customer to listen to music through the headphones so that the customer can assess the sound quality. The customer may wish, for example, to plug the headphones into his or her MP3 player or mobile phone so that the customer can listen, through the headphones, to music with which the customer is familiar
[0003] When allowing customers to try out headphones as described above, it is also desirable to secure the headphones to a fixture, such as a display stand, so that the headphones cannot be stolen.
SUMMARY
[0004] In accordance with a first aspect of the invention, there is provided a security device for securing a jack plug during retail display of a product fitted with a jack plug, the security device comprising: a jack plug socket for engagement with a jack plug and operable to lock a jack plug in said engagement so as to resist withdrawal of the jack plug, an input for receiving electrical signals, the input being electrically connected to the jack plug socket so that electrical signals received at the input are transmitted to the jack plug socket for transmission of the electrical signals from the jack plug socket to a jack plug locked in engagement with the jack plug socket and for onward transmission of the electrical signals to a product connected to the jack plug, and an attachment for attaching the security device to a fixture.
[0005] Accordingly, the security device of the current invention allows a retail product to be secured by securing the jack plug connected to the product. It will be appreciated that the security device can be used with other retail products fitted with a jack plug. The use is not limited to pairs of headphones.
[0006] The term “jack plug” is used to signify an electrical male plug having a single, generally cylindrical pin provided with a plurality of contact areas along its length and the term “jack plug socket” is used to refer to the corresponding female socket. Jack plugs are also commonly known as audio jacks or phone jacks. The term jack plug includes all sizes (e.g. with 2.5 mm, 3.5 mm and 6.35 mm diameter pins). The term jack plug also covers plugs with any plural number of contacts. For example, an audio stereo jack plug commonly has three contacts and is often referred to as a TRS plug (the initials TRS referring to the three contact areas of the pin known as Tip, Ring and Sleeve). An audio mono jack plug commonly has two contacts and is often referred to as a TS (Tip, Sleeve) plug. A four contact plug is commonly referred to as a TRRS (Tip, Ring, Ring, Sleeve) plug. Jack plugs having greater numbers of contacts are available. All such plugs are included within the term “jack plug” and the corresponding jack plug sockets are included within the term “jack plug socket”. The terms “jack plug” and “jack plug socket” are not limited to audio plugs and sockets and also cover all other uses, such as a microphone plug having a cylindrical configuration and the corresponding socket. In general, the tip of a jack plug is separated from ring and sleeve contacts on the jack plug by a neck. The tip generally includes a convex frusto-conical surface which faces generally radially outwardly and rearwardly (ie towards a handle portion of the jack plug).
[0007] Preferably, the security device includes a housing. The jack plug socket is provided in the housing and the attachment allows attachment of the housing to a fixture. In this way, the housing protects and hides the locking mechanism of the jack plug socket.
[0008] Preferably, the jack plug socket comprises a locking member which is moveable between a locking position and a release position. When the locking member is in the release position, the jack plug can be withdrawn from the jack plug socket. The locking member is lockable in the locking position to lock the jack plug within the jack plug socket. When the locking member is in the locking position, the locking member engages a tip of a jack plug. In this case, the shape of the tip of the jack plug allows the locking member to achieve purchase on the jack plug. In this way, locking of the jack plug within the jack plug socket can generally be achieved without deforming the pin of the jack plug.
[0009] Where the jack plug socket has a locking member as described above, the locking member preferably has a concave frusto-conical surface. In this case, the security device is used with a jack plug having a tip which has a convex frusto-conical surface. By providing the locking member with a concave frusto-conical surface which corresponds closely in shape to the convex frusto-conical surface of the tip of the pin of a jack plug, it has been found possible to achieve secure locking of a jack plug within a jack plug socket.
[0010] Where a locking member is provided, the jack plug socket preferably also comprises a rotatable control member which interacts with the locking member. The rotatable control member is rotatable between a first stop at which the locking member is locked in the locking position and a second stop at which the locking member is in the release position. The provision of the two distinct stops is advantageous compared to, for example, a locking screw which can be tightened or loosened without any distinct stops to limit its rotation. The provision of these stops avoids over tightening.
[0011] Where the jack plug socket comprises both a locking member and a rotatable control member, as described above, the locking member preferably has a first end and a second end. The first end is pivoted and the second end of the locking member interacts with the rotatable control member to control movement of the locking member between the locking position and the release position. Where a concave frusto-conical surface is provided on the locking member, this is preferably intermediate the first and second ends of the locking member. In this way, a high degree of positional accuracy of the frusto-conical surface may be achieved.
[0012] When the jack plug socket is provided with a rotatable control member, the security device preferably also includes a security key. The rotatable control member has a formation which is shaped for engagement with the security key so that the rotatable control member can be rotated by the security key between the first and second stops. Even more preferably, the shape of the formation on the rotatable control member is such that it cannot be engaged by a screwdriver with a slot head or a cross-head. In this way, even if a potential customer is able to gain access to the jack plug socket, the customer may not be able to release the jack plug without a security key which corresponds to the formation on the rotatable control member.
[0013] The input of the security device may be any suitable input. It could, for example, be a standard jack plug socket without a locking function. It could also be, for example, a standard USB socket. In one specific embodiment, the input is itself a jack plug which a potential customer can plug into his or her MP3 player or mobile phone.
[0014] In accordance with a second aspect of the invention, there is provided a method of securing a jack plug during retail display of a product fitted with a jack plug, comprising providing a product fitted with a jack plug, providing a security device, securing the security device to a fixture, locking the jack plug in engagement with the security device, and providing an input. The input being electrically connected to the jack plug so that electrical signals received at the input are transmitted to the jack plug for onward transmission of the electrical signals to the product.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The following is a more detailed description of embodiments of the invention, by way of example, reference being made to the following schematic drawings in which:
[0016] FIG. 1 is an isometric view of a security device from which an external lid and an intermediate lid have been omitted in order to show the internal components;
[0017] FIG. 2 is a plan view from above of the security device of FIG. 1 ;
[0018] FIG. 3 is a cross-sectional view of the security device of FIGS. 1 and 2 ;
[0019] FIGS. 4 to 8 are isometric views showing components of a jack plug socket of the security device of FIGS. 1 to 3 ;
[0020] FIG. 9 is a plan view from above of the security device of FIGS. 1 to 8 showing an intermediate cover in place in the security device;
[0021] FIG. 10 is a plan view from above of the security device of FIGS. 1 to 9 showing an outer cover in place on the security device.
DETAILED DESCRIPTION
[0022] Looking first at FIGS. 1 , 2 , 9 and 10 , the security device includes a casing bottom 10 , an intermediate lid 12 , an outer lid 14 , a locking jack plug socket generally shown at 16 , and an input in the form of a standard jack plug socket 18 .
[0023] As best seen in FIG. 1 , the casing bottom 10 is provided with two upstanding attachment bosses 20 . Each attachment boss 20 has a central hole which passes through the casing bottom 10 . In this way, the attachment bosses 20 can be used to attach the casing bottom 10 to a fixture, such as a wooden display stand, by passing two screws through the attachment bosses 20 into the underlying wooden fixture. In addition, the casing bottom 10 is provided with two upstanding support bosses 22 . Each support boss 22 is provided with a blind threaded hole which, as seen best in FIG. 9 , receives a threaded bolt so as to attach the intermediate lid 12 to the casing bottom 10 . The casing bottom 10 also has an L-shaped rebate 24 which extends around the casing bottom 10 and which receives the outer lid 14 as described below in more detail.
[0024] As best seen in FIGS. 1 and 3 , the casing bottom 10 also has a first aperture 26 which receives the pin of a jack plug to be engaged in the locking jack plug socket 16 and a second aperture 28 which receives the pin of a jack plug to be engaged in the standard jack plug socket 18 . The standard jack plug socket 18 is omitted from FIG. 3 for the purposes of clarity.
[0025] Looking now at FIGS. 1 and 3 , a connection plate 30 is provided near to but spaced from a bottom wall of the casing bottom 10 . The locking jack plug socket 16 and the standard jack plug socket 18 are both mounted on the connection plate 30 . Electrical connections (not shown) are provided on the underside of the connection plate 30 to connect the locking jack plug socket 16 with the standard jack plug socket 18 . In this way, electrical input signals provided to the standard jack plug socket 18 by a jack plug inserted in the standard jack plug socket 18 are transmitted to the locking jack plug socket 16 so that the locking jack plug socket 16 can transmit the electrical signals to a jack plug engaged with the locking jack plug socket 16 .
[0026] The standard jack plug socket 18 is conventional in design and will not be described in detail.
[0027] Referring now to FIGS. 1 to 8 , the locking jack plug socket 16 includes a locking arm 32 , a control screw 34 and a pair of pivot mounts 36 . The locking arm 32 is best seen in FIG. 6 which shows the underside of the locking arm 32 . As shown in FIG. 6 , a first end of the locking arm 32 is provided with a pair of pivot pins 38 . As shown in FIG. 1 , the pair of pivot pins 38 co-operate with the pivot mounts 36 to allow the locking arm 32 to pivot around the axes of the pivot pins 38 . As seen in FIG. 1 , the pivot mounts 36 do not prevent upward movement of the pivot pins 38 out of engagement with the pivot mounts 36 . However, two projections (not shown) are provided on the underside of the intermediate lid 12 so that when the intermediate lid 12 is fixed to the casing bottom 10 as described above, the projections on the underside of the intermediate lid 12 bear against the pair of pivot pins 38 and prevent any upward movement of the pivot pins 38 . In this way, the locking arm 32 is constrained so that only pivoting movement around the axes of the pivot pins 38 is allowed.
[0028] The second end of the locking arm 32 is provided with a locking ring 40 . The locking ring 40 cooperates with the control screw 34 , as described below, to achieve movement of the locking arm 32 between a locking position and a release position.
[0029] As shown in FIG. 6 , the underside of the locking arm 32 is provided with a frusto-conical recess 42 . This serves a purpose described below.
[0030] The control screw 34 is best seen in FIGS. 1 , 4 , 5 , 7 and 8 . As seen, for example, in FIGS. 1 and 4 , the locking screw 34 is engaged, by way of corresponding screw threads, with a nut 44 which is fixed to the bottom wall of the casing bottom 10 . In this way, if the control screw 34 is rotated in a clockwise direction (as seen from above), the control screw 34 moves downwardly into the nut 44 . If the control screw 34 is rotated in an anti-clockwise direction (as seen from above), then the control screw 34 moves upwardly relative to the nut 44 .
[0031] The top end of the control screw 34 is provided with a security formation in the form of a truncated pyramid 46 . This truncated pyramid 46 is shaped so as to engage with a security key (not shown). The security key is used to rotate the control screw 34 either in a clockwise or anti-clockwise direction.
[0032] Immediately below the truncated pyramid 46 , the control screw 34 is provided with a locking disc 48 . The locking disc 48 cooperates with the locking ring 40 of the locking arm 32 to control movement of the locking arm 32 between a locking position and a release position, as will now be described.
[0033] As best seen in FIGS. 5 and 7 , the locking ring 40 of the locking arm 32 has, on its upper surface, a cam surface 50 . Adjacent to the cam surface 50 , the locking ring 40 of the locking arm 32 also has a stop surface 52 .
[0034] As best seen in FIG. 8 , the underside of the locking disc 48 of the control screw 34 also has a cam surface 54 . Adjacent to cam surface 54 , the locking disc 48 of the control screw 34 has a stop surface 56 which can be seen in FIG. 7 .
[0035] FIGS. 5 , 7 and 8 show the locking arm 32 in a release position. FIGS. 5 and 8 also show a jack plug 60 which is engaged with, but not locked with, the locking jack plug socket 16 . In the release position of the locking arm 40 , as shown in FIGS. 5 , 7 and 8 , the jack plug 60 can be withdrawn from the locking jack plug socket 16 simply by pulling the jack plug 60 out of the locking jack plug socket 16 .
[0036] However, the security key (not shown) can be engaged with the truncated pyramid 46 of the control screw 34 and the security key is then used to rotate the control screw 34 in a clockwise direction (as seen from above). This causes the control screw 34 and the locking disc 48 to move downwardly into/towards the nut 44 . During this process, the cam surface 54 on the locking disc 48 moves against and along the cam surface 50 on the locking ring 40 of the locking arm 32 . The engagement of the two cam surfaces 50 , 54 and the downward movement of the control screw 34 , moves the locking arm 32 downwardly from the position shown in FIG. 8 . The distance of movement is relatively small.
[0037] This process continues until the stop surface 56 on the locking disc 48 of control screw 34 contacts the stop surface 52 on the locking ring 40 of the locking arm 32 . After contact between the two stop surfaces 52 , 56 no further clockwise motion of the control screw 34 is possible. At this point, the locking arm 32 is in the locking position, and this is shown in FIG. 3 .
[0038] As seen in FIG. 3 , the jack plug 60 is of conventional design and has a jack plug tip shown at 62 . The jack plug tip 62 has a convex frusto-conical surface indicated at 64 . In the current locking position of the locking arm 32 , the concave frusto-conical surface of the recess 42 of the locking arm 32 (best seen in FIGS. 3 and 6 ) fits closely against the convex frusto-conical surface 64 of the tip 62 of the jack plug 60 . The two frusto-conical surfaces 42 , 64 (one being convex and the other being concave) correspond closely in shape and this provides an effective locking mechanism preventing withdrawal of the jack plug 60 from the locking jack plug socket 16 .
[0039] As best seen in FIGS. 3 and 8 , a bracing rib 66 extends upwardly from the bottom wall of the casing bottom 10 and this bracing rib 66 serves to prevent downward movement of the jack plug 60 which would otherwise reduce the effectiveness of the locking of the jack plug 60 within the locking jack plug socket 16 . It will be appreciated that additional bracing ribs may be provided, either extending upwardly from the casing bottom 10 , or extending downwardly from the underside of the intermediate lid 12 . In this way, any tilting of the jack plug 60 when engaged within the locking jack plug 16 may be prevented.
[0040] In order to unlock the locking jack plug socket 16 , so as to allow removal of the jack plug 60 , the control screw 34 is rotated in an anticlockwise direction whereupon the two cam surfaces 50 , 54 move against each other back into the unlocking position shown in FIGS. 5 and 8 . This causes a small upward movement of the locking arm 32 which is sufficient to allow withdrawal of the jack plug 60 . At the rotational position of the control screw 34 shown in FIGS. 5 and 8 , no further anticlockwise rotation of the control screw 34 is possible due to contact between two additional stop surfaces (not shown).
[0041] As best seen in FIGS. 3 and 5 , the jack plug 60 is of a type referred to as TRS. In other words, the tip 62 forms a first electrical contact, a ring 68 forms a second electrical contact and a sleeve 70 forms a third electrical contact. As best seen in FIG. 3 , the locking jack plug socket 16 has first, second and third electrical contacts 72 , 74 , 76 . The first electrical contact 72 forms an electrical contact with the tip 62 . The second electrical contact 74 forms an electrical connection with the ring 68 and the third electrical contact 76 forms an electrical connection with the sleeve 70 . Each one of the first, second and third electrical contacts 72 , 74 , 76 is spring loaded urging the electrical contacts 72 , 74 , 76 against the corresponding part of the jack plug 60 . The electrical contacts 72 , 74 , 76 are in electrical connection with the electrical connectors on the underside of the connection plate 30 .
[0042] The upper surface of the intermediate lid 12 is shown in FIG. 9 . FIG. 9 also shows two bolts 80 which pass through respective holes in the intermediate lid 12 and are received in the support bosses 22 in order to fix the intermediate lid 12 securely against the casing bottom 10 . As seen in FIG. 9 , the intermediate lid 12 has three bayonet type slots 82 which cooperate with three corresponding bayonet projections (not shown) on the underside of the outer lid 14 in order to fix the outer lid 14 to the casing bottom 10 . The intermediate lid 12 also has an aperture 84 which corresponds in position with the truncated pyramid 46 of the control screw 34 so that the security key can be passed through the aperture 84 to operate the control screw 34 .
[0043] A slot 86 is also provided in the intermediate lid 12 to facilitate lifting of the intermediate lid 12 out of the casing bottom 10 .
[0044] In operation, the security device is fixed to a fixture using the attachment bosses 20 as described above. In this example, the security device is used to secure a pair of headphones on retail display. The jack plug 60 of the headphones is inserted into the locking jack plug socket 16 . A retail assistant then removes the outer lid 14 by rotating the outer lid 14 so as to reveal the intermediate lid 12 . There is no need to remove the intermediate lid 12 . The retail assistant uses the security key to rotate the control screw 34 in a clockwise direction which causes the locking arm 32 to move from the release position to the locking position as described above. The jack plug 60 is now locked in the locking jack plug socket 16 . The retail assistant replaces the outer lid 14 .
[0045] A potential customer is now able to listen to music through the headphones. In order to do this, a connecting cable (not shown) having a jack plug at each end is used. One of the jack plugs of the connecting cable is inserted into the standard jack plug socket 18 of the security device. The other jack plug of the connecting cable is inserted into the customer's MP3 player or mobile phone. Electrical signals carried by the connecting cable to the standard jack plug socket 18 are passed to the locking jack plug socket 16 and the music can be heard in the headphones. The locking of the jack plug 60 in the locking jack plug socket 16 prevents theft of the headphones.
[0046] It will be appreciated that the security device need not be as described above and many adaptations may be made while remaining within the scope of the appended claims.
[0047] For example, while the locking mechanism described above has been found to be very effective, any locking mechanism capable of holding a jack plug within a locking jack plug socket may be used.
[0048] In addition, it is not necessary to provide a standard jack plug socket 18 . Instead, the security device may be provided with a jack plug of its own connected to the locking jack plug socket 16 by a cable fixed to the casing. The jack plug of the security device can then be simply inserted into the MP3 player or mobile phone of the customer.
[0049] Alternatively, the security device could be provided with any other type of input, such as a USB socket or USB plug. | A security device for securing a jack plug during retail display of a product, such as a pair of headphones, that is fitted with a jack plug. The security device comprises a jack plug socket for engagement with the jack plug of the product and operable to lock the jack plug so as to prevent withdrawal of the jack plug from the jack plug socket. In addition, the security device has an input for receiving electrical signals from a source, such as an MP3 player or a mobile phone. The input is electrically connected to the jack plug socket so that electrical signals received at the input are transmitted to the jack plug socket. In addition, the security device is provided with an attachment for attaching the security device to a fixture such as a retail display. | 7 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to a method, a system, and a computer program product for automatically determining a transaction tax liability for a transaction involving the sale of products or services. The burden on sellers and buyers to comply with transaction tax laws and rules in all jurisdictions in which they do business is extraordinary, and is made complicated by the numerous taxes that may be applicable in each jurisdiction involved in the transaction. Consummated transactions may be subject to many different tax schemes, including, but not limited to, customs, excise, sales, and use taxes, gross receipts taxes, utility taxes, business and occupation taxes, and value added taxes. Federal, state, and local governments around the world have the legal authority to enact transaction taxes, and tens of thousands of taxing jurisdictions are in place today. The methods and rates of taxation vary widely and are often changed.
[0002] Transaction tax liabilities related to the consummation of a transaction are typically calculated at the time of the transaction by the seller at the seller's location at the time of transaction (either in-person or online) or with an invoice. In either case, but particularly in the case of time-of-transaction tax calculation, the requirement of resorting to multiple tax tables for different applicable jurisdictions, for which each table may be extensive, is extremely demanding even for electronic cash registers deployed at most retail locations.
[0003] Automation solutions in the past have included, as an example, U.S. Pat. No. 6,141,650, for “Sales Data Processing System Capable of Automatically Calculating Sales Taxes,” issued to Iwasa et al. the applicable tax authority, possibly an expensive administrative proposition for the purchaser. Iwasa et al. teaches the input of a tax table into an electronic cash register using an algorithm for detecting cyclical series of difference values.
[0004] Such an approach, while useful for programming an electronic cash register for one (or a relatively few tables), is not manageably extendible to the situations of online or mail order retailers who have facilities in multiple jurisdictions or multi-jurisdictional retail “chains” with centralized tax calculation, who are thus faced with multiple tables with multiple rules that are changed from time to time.
SUMMARY OF THE INVENTION
[0005] A hybrid algorithm- and table-based system is provided in the invention to allow flexible and real-time automated transaction tax calculation. In a preferred embodiment of the invention, an invoice tax engine deconstructs an invoice into taxable line items, for each of which a line item tax engine calculates an unrounded tax on a transaction using both an algorithm and a table. A rounding function is used to calculate true total tax for accumulated line item tax and for accumulated invoice tax. That rounding function applies specific rules of the taxing jurisdiction.
BRIEF DESCRIPTTON OF THE DRAWINGS
[0006] [0006]FIG. 1 is a data flow diagram of the invoice tax engine of the present invention;
[0007] [0007]FIG. 2 is a data flow diagram of the line item tax engine of the present invention; and
[0008] [0008]FIG. 3 is a data flow diagram of the rounding function of the present invention.
DETAILED DESCRIPTION
[0009] [0009]FIG. 1 shows the operation of the invoice tax engine in a specific embodiment. In the first step 15 , the invoice tax engine receives an invoice in digital form. The invoice tax engine 10 then sends each line of the invoice to the line item tax engine 60 (FIG. 2) line-by-line. In step 25 , shown in greater detail in FIG. 2, the line item tax engine 60 calculates the unrounded tax for the line item, generally matching the transaction represented by the invoice with a tax table (or set of rules) for a particular taxing jurisdiction among many, for example, the “taxbkt” Table 3 below, and calculating a tax according to those rules. In step 30 , the invoice tax engine 10 accumulates (by repeating steps 20 and 25 ), according to a flag in the “taxrnd” table, which is laid out as follows:
TABLE 1 Layout of TAXRND Table Field Data type Field length State Num 2 Rate Num 7, 6 Effective date Num 8, 0 Expiration date Num 8, 0 Rounding type Char 1 Standard or exception Char 1 Exclusion/exemption Char 1 Exclusion threshold Num 7, 2 Rounding Threshold Num 7, 2 Rounding Amount-1 Num 7, 6 Rounding Amount-2 Num 7, 6
FIELD DESCRIPTIONS
[0010] State Code
[0011] The numeric state code. The system recognizes Canada as state code 52 . The Canadian provinces are listed separately.
[0012] Rate
[0013] All states have a record with 0 in the rate field. States where the rounding varies by rate have additional rate records.
[0014] Effective Date
[0015] The date on which the rounding method became effective. The baseline effective date is 00000000.
[0016] Expiration Date
[0017] The date on which the rounding method expired. If the method is still valid, the expiration date is zeroes.
[0018] Standard or Exception:
[0019] “S” indicates that all rates in the state use the same method of rounding as the one described on the zero rate record.
[0020] “E” indicates that some form of special processing is necessary.
[0021] Rounding Type
[0022] “A” means the same as “T” except that a city or county accumulates and rounds separately from the rest of the state. As the System examines each line item to be accumulated, it compares the state, level and county or city name to the records in a supplemental table. If the name(s) are found, the System accumulates the tax for that name and level separately from the remainder of the tax. The System applies type “T” rounding rules to the accumulated exception city tax and to the accumulated “all other” tax.
[0023] “B” indicates that taxable amounts below the exclusionary threshold have no tax; taxable amounts above the non-zero rounding threshold are rounded using the rules in this table; taxable amounts between the exclusionary and rounding thresholds use the rules in table taxbkt (below).
[0024] “C” is a combination of “B” and “L”. The program accumulates and rounds taxes by level. The state total is rounded using the state's base record and rounding type “B”. The city/county totals are rounded individually using the rules on a record with the city/county rate. If the local record is not found, the program defaults to 5/4 rounding.
[0025] “L” indicates that each level of tax is to be rounded individually.
[0026] “Q” indicates that Canadian state level tax (GST) is rounded first, the result used in a tax on tax calculation, and the city level PST rounded separately. (State and city refer to the field names.)
[0027] “T” indicates the tax shall be rounded by total rate. If rounding is controlled by the UTL, it is applied to the total tax for all invoice lines with the same rate. If rounding is controlled by TAX010, it shall be applied to the total tax for each line. Example: Georgia 7%=4% county +1%+1%+1% locals. Rounding must be on the total invoice 7% tax.
[0028] “X” indicates the invoice total tax for each level is rounded as one sum. Example: In some Canadian PST provinces, the total GST and total PST are rounded separately.
[0029] Exclusion/Exemption
[0030] “T” taxable sales on or below the exemption threshold are reported as taxable.
[0031] “E” taxable sales on or below the exemption threshold are reported as exempt.
[0032] Where this is no threshold, the record will show C.
[0033] Exemption Threshold
[0034] The highest taxable sales amount at which no tax is due whether or not tax is calculated. If there is no threshold, or if there is no tax, the table will show zero.
[0035] Rounding Threshold
[0036] Tax on taxable sales above the exemption threshold but not above this threshold is rounded using the low rounding amount.
[0037] Low Rounding Amount
[0038] This amount is added to the tax amount for transactions with a taxable amount greater than the exemption threshold, and not greater than the rounding threshold.
[0039] High Rounding Amount
[0040] This amount is added to the tax amount for transactions with a taxable amount greater than the rounding threshold.
[0041] When the cycling through steps 20 and 25 is completed, in step 35 , the invoice tax engine passes the totals to the rounding function 100 (FIG. 3), which, in step 40 , calculates the true total tax, that is, the rounded tax. The invoice tax engine 10 then determines the difference between the accumulated and the calculated invoice tax in step 45 . Finally, the invoice tax engine in step 50 distributes any difference between the line items and then between the levels of multiple tax jurisdictions that may be applicable to the transaction. If the rounded total tax in dollars and cents is not equal to the total tax produced by accumulating dollars and cents for each line item, the system applies the difference proportionately by taxable gross. The results are then returned at step 55 to a receipt or invoice generation module.
[0042] The operation of the line item (or line) tax engine 60 is shown in FIG. 2. As a first step 65 , the line tax engine receives a transaction, which may be a line item or an invoice total line (here it is a line item). The line tax engine 60 then calculates tax on a transaction at step 70 . The line item tax is accumulated in step 75 (which may use the same accumulator as for step 30 ) according to a flag in “taxrnd”. The line tax engine 60 then passes the totals (which may be multiple totals according to the flag) in step 80 to the rounding function 100 (FIG. 3). In step 85 , the rounding function calculates the true total tax. The line tax engine 60 then determines the difference between the accumulated and the calculated tax in step 90 and distributes any difference between tax jurisdiction levels in step 95 . (If the true tax amount is less than the accumulated amount, then reduce the lowest level with tax (secondary city upwards to state) until the two totals are the same; if the true tax amount is greater than the accumulated amount, then increase the highest level with tax (state, county, city, etc.) until the two totals are the same.) The results are passed back to the invoice tax engine 10 in step 99 .
[0043] [0043]FIG. 3 shows the operation of the rounding function 100 . In the first step 110 , a base current record for the state is read from the rounding table “taxrnd”. At branch point 120 , the rounding function 100 determines whether the state uses standard or exception processing. Exceptions are addressed using an exception table, in a particular embodiment called the “txrndexc” table. Following is a portion of the “txrndexc” table showing locations in Arkansas with a 3% applicable tax:
TABLE 2 Layout of TXRNDEXC Table State Level Code Name AK 4 A Alakanuk AK 4 F Ambler AK 4 B Angoon AK 4 C Aniak AK 4 A Bethel AK 4 N Brevig Mission AK 4 L Chevak AK 4 D Diomede AK 4 K Emmonak AK 4 G Fort Yukon AK 4 E Galena AK 4 D Gambell AK 4 F Kotlig City AK 4 I Haines AK 4 C Ketchikan AK 4 A Klawock AK 4 N Larsen Bay AK 4 H Nenana AK 4 A Ouzinkie AK 4 C Palmer AK 4 C Petersburg AK 4 B Quinhagak AK 4 J Sandy Point AK 4 L Savoonga AK 4 B Seward AK 4 B Thorne Bay
[0044] If there is exception processing, there is a branch to step 125 , in which a matching rate record is read. (Thus, the system uses the “txrndexc” code field to map cities and counties to records on the “taxrnd” table using the “Standard or exception” field in the “taxrnd” table.) At branch point 130 , the rounding function determines whether the taxable amount is less than or equal to an exclusion threshold (given in the “taxrnd” table) and if so, the tax is set to zero in step 135 and returned to the calling engine in step 180 . If not, at branch point 140 , the rounding function determines whether the tax is greater than a non-zero rounding threshold, and if so, a “high rounding amount” (provided in the “taxrnd” table) is added to the unrounded tax amount, and the result is truncated (in the same procedure as the “add high rounding amount procedure”) to zero in step 145 and returned to the calling engine in step 180 . If not, at branch point 150 , the rounding function determines whether the rounding type is equal to “T/L/Q/A”, and if so, a “low rounding amount” is added to the tax and the result truncated to two decimals, that is, to whole cents, at step 155 and returned to the calling engine in step 180 . If not, at branch point 160 , the rounding function determines whether the rounding type is “B/C”, and if so, the rounding function reads the first record in the bracket (“taxbkt”) table based on state, rate and date in step 162 , applies bracket taxing according to the rule on the record in step 165 , and returns the result to the calling engine in step 180 . The layout of the “taxbkt” table follows:
TABLE 3 Layout of TAXBKT Table Length, Field Data type decimals Position State/Province Num 2 1-2 Rate Num 7, 6 3-9 Exception code Char 3 10-12 Effective date Num 8, 0 13-20 Upper limit of range Num 6, 2 21-26 Tax amount OR Upper Num 6, 2 27-32 limit of table. Calculation Rule OR Char 2 33-34 Remainder limit Maximum taxable for Num 6, 2 35-40 the rule OR the repetition factor
FIELD DESCRIPTIONS
[0045] State Code
[0046] 2-digit state code. Canada is 52. The system assigns state codes 81-93 to the Canadian provinces.
[0047] Rate
[0048] The rate for the bracket as a multiplying factor. Example: 6%=0.060000 which appears in the table as 0060000.
[0049] Exception Code
[0050] Reserved for future use; allows for additional flexibility.
[0051] Effective Date
[0052] The date on which the brackets became effective.
[0053] Upper Limit of Range
[0054] The first record for each state and rate combination contains zeroes. The other records contain the highest value of a bracket.
[0055] Tax Amount OR Upper Limit of Table
[0056] The first record for each state and rate combination has zeroes in the upper limit of range field and the upper limit of the table in this field. Other records contain the amount of tax that applies to a range.
[0057] Calculation Rule OR Remainder Limit
[0058] The calculation rule is a code indicating the bracket tax method for all taxable amounts. The remainder limit is a code indicating a change of focus during the table look-up.
[0059] Upper Limit of Rule OR the Repetition Factor
[0060] The first record for each state and rate combination contains a value indicating the limit of the rule or the repetition factor. When the field is zero, no limit applies and there is no non-standard repetition factor. When a taxable amount exceeds the value of the non-zero upper limit of the rule, the System will round the tax using the high rounding amount in table taxrnd. The value of the upper limit of rule should also be in the field known as “rounding threshold” in table taxrnd. Its presence here is a safety valve. When the base tax amount used for multiplying whole units above the upper limit of table is not the same as the last value in the table, the repetition value is used to determine the number of units and the tax on those units.
[0061] If the rounding type is not “B/C”, a “high rounding amount” stored in table is added to the unrounded tax amount and the result truncated to two decimals (to whole cents) in step 170 and returned to the calling engine at step 180 .
[0062] Note that, while the example here was given of multiple taxing jurisdiction levels, the invention is applicable to different line items with different rounding rules and to combinations of such rules with different jurisdictions.
[0063] A computer system with which the various elements of the tax transaction system including the invoice tax engine 10 , the line tax engine 60 and the rounding function 100 may be implemented in a variety of ways. The computer system may be a general purpose computer system which is programmable using a computer programming language, such as C, C++, Java, or other language, such as a scripting language or even assembly language. The computer system may also be specially programmed, have special purpose hardware, or have an application specific integrated circuit (ASIC).
[0064] Such a system may be implemented in software, hardware, or firmware, or any combination thereof. The various elements of the system, either individually or in combination, may be implemented as computer program product tangibly embodied in a machine-readable storage device for execution by a computer processor. Various steps of the process may be performed by a computer processor executing a program tangibly embodied on a computer-readable medium to perform functions by operating on input and generating output. Computer programming languages suitable for implementing such a system include procedural programming languages, object-oriented programming languages, and combinations of the two.
[0065] The invention is not limited to a particular computer platform, particular processor, or particular high-level programming language. Additionally, the computer system may be a multiprocessor computer system or may include multiple computers connected over a computer network. Various possible configurations of computers in a network permit many users to participate in a transaction, even if they are disbursed geographically.
[0066] Each module or step shown in the accompanying Figures and the sub-steps or subparts shown in the remaining Figures may correspond to separate modules of a computer program, or may be separate computer programs. Such modules may be operable on separate computers or other devices. The data produced by these components may be stored in a memory system or transmitted between computer systems or devices. A communication network may interconnect the plurality of computers or devices, such as a public switched telephone network or other circuit switched network, or a packet switched network such as an Internet protocol (IP) network. The network may be wired or wireless, and may be public or private.
[0067] Having now described the preferred embodiment, it should be apparent to those skilled in the art that the foregoing is merely illustrative and not limiting, having been presented by way of example only. Numerous modifications and other embodiments may be made. For example, the tax transaction system may be applied to any type of tax that must be collected and remitted, including, but not limited to telecommunications, transportation, utilities, and other transaction taxes. | A transaction tax calculating system using a hybrid method of referring to tables providing rules for state and local tax brackets, rounding and exceptions and applying those rounding and bracket tax calculation rules in conjunction for rounding. | 6 |
BACKGROUND OF THE INVENTION
This invention relates generally to an electrical wiring or conductor interconnect structure for a semiconductor device, integrated circuit or the like and in particular to a combination electrical wiring and passive element in an integrated circuit structure of a semiconductor device, such as, in a high resistance load type static RAM (SRAM) with a wiring interconnect including an integrated resistance for connection between a voltage source and a diffusion layer representing a terminal domain of an integrated active element, e.g., a MOSFET source or drain.
It is known in the prior art to provide integrated buried wiring interconnections in the fabrication of integrated circuits, such as, for example in the case of high resistance load type static RAM's or SRAM. One such example is disclosed in Japanese Patent Laid Open No. 130461/1982 and is exemplified in FIGS. 3 and 4. In order to fully appreciate the present invention, it is first desirable to discuss the state of the art relative to wiring interconnects in conventional high resistance polycrystalline silicon load type memory cells in order to better understand and appreciate the improvements brought about by the present invention. FIG. 4 illustrates the schematic representation of a conventional high resistance polycrystalline silicon load type memory cell comprising a flip flop for storing information with an output of one of two inverters, comprising series connected MOSFET Q 1 and resistance R 1 and series connected MOSFET Q 2 and resistance R 2 , with each inverter connected as an input to the other. These flip flop circuits are combined with two switching MOSFETS's Q 3 and Q 4 connected to the write line (WL) for exchanging information externally of the cell via data lines DL and bar DL.
FIG. 3 illustrates a cross sectional portion of the integrated circuit structure for the storage FF circuit schematic shown in FIG. 4. The structure comprises a p-type silicon substrate upon which are formed regions of field insulating film 2, e.g., SiO 2 , beneath which are formed p-type channel stopper domains 3 to prevent the formation of parasitic channels. A gate insulating film 4, for example SiO 2 , is provided on the surface of each active element domain comprising Q 1 through Q 4 , which domains are surrounded by field insulating film 2. Active domains shown in the FIG. 3 cross section disclose only MOSFET's Q 1 and Q 3 .
A word line of predetermined form comprises a double layer film of polycrystalline silicon film 5 and high temperature or fusing point metal silicide or polycide film 6, which form gate electrode 7 and the gate for MOSFET Q 3 bounded by side walls 11. These films are directly deposited on gate insulating film 4 and field insulating film 2. An n + -type source domain 9 and n + -type drain domain 10 are formed relative to each active element comprising a MOSFET, and are surrounded by field insulating film 2, and are in alignment with a word line, WL, gate electrode 7 and grounding conductor SL.
An interlayer insulating film 12, for example SiO 2 , is deposited over the double layer films 5, 6 and MOSFET's Q 1 and Q 3 . A first contact hole 16 is then formed in interlayer insulating film 12 and thereafter a wiring layer 15 comprising a polycrystalline silicon film of predetermined form is deposited thereon. Wiring layer 15 includes n + -type polycrystalline regions 15A and 15B and high resistance polycrystalline silicon resistances R 1 , R 2 wherein, as seen in FIG. 3, only R 2 is visible. Region R 1 or R 2 comprise an intrinsic polycrystalline silicon film 15C, which is integral with regions 15A and 15B of n + -type polycrystalline film and all together form wiring layer 15. Next, a second interlayer insulating film 17, for example, a PSG film, is formed on wiring layer 15 followed by the deposition of data lines DL and bar DL (only line DL is visible in FIG. 3). Data lines DL and bar DL are connected respectively to drain domains 10 of MOSFET's Q 3 and Q 4 via the formed contact hole 21, as shown relative to Q 3 in FIG. 3.
Resistance R 1 , R 2 may be formed as follows. Wiring layer 15 is first deposited as a nondoped or intrinsic polycrystalline silicon film over the surface of interlayer insulating film 12. Next, a portion of the deposited intrinsic polycrystalline silicon film to function as a high resistance polycrystalline silicon resistance is covered by a masking layer and the remaining portions of layer 15 are exposed to a diffusion process with an impurity, such as, phosphorous (P) or arsenic (As) and ion implantation or other type of incorporation method. The masking layer is then removed, producing a polycrystalline silicon film 15 having a pattern of predetermined form comprising wiring or conductor sections 15A and 15B of n + polycrystalline Si film, enhanced in conductivity by introduction of phosphorous or arsenic, and high resistance, intrinsic polycrystalline silicon regions 15C forming resistance R 1 and R 2 .
Under present practice, the sizes of the polycrystalline silicon resistances R 1 and R 2 are determined by the spatial relation between contact hole 16 and power source V DD at the other end of wiring layer 15. Thus, as best illustrated in FIG. 4, resistances R 1 , R 2 are connected to the source domains of MOSFET's Q 1 through Q 4 via wiring layer 15. The other ends of resistances R 1 , R 2 are connected to power source V DD . The drains of MOSFET's Q 1 and Q 2 are connected to ground. Word line, WL, is connected to the gate electrodes of MOSFET's Q 3 and Q 4 and data lines DL and bar DL are connected to the drains of MOSFET's Q 3 and Q 4 via contact hole 21.
There remains, however, a problem in connection with the above described memory cell structure in that a refined construction and reduction in integrated circuit scale is not realizable. This problem is exemplified in the disclosure of Yoshio Sakai, "CMOS-SRAM Process Device Art", 28th Semiconductor Special Course Draft, pp. 69-114, wherein it is explained, that as the size of resistances R 1 and R 2 are shortened to refine the scale of the transistor structure, their resistance values become rapidly low. This is illustrated in the diagram of FIG. 5. Therefore, a desired high resistance value is difficult to obtain or retain since resistance values will be naturally reduced in value with any reduction in the integrated circuit scale. As a result, in the particular case of a SRAM, the consumption current during standby will accordingly increase. Therefore, a certain reasonable size, currently about 3 microns or more, is necessary, which is a big obstacle toward the realization of a refined memory cell construction and a reduction in memory cell scale. Further, it is presently believed that, in the future, the size of such a memory cell will be governed by the required sizes of the resistance R 1 and R 2 and, as a result, this problem of scale will become even more intensified.
SUMMARY OF THE INVENTION
According to this invention, interconnect means is provided to extend values for integrated passive elements, such as resistances R 1 and R 2 in a SRAM explained above, while also maintaining the desired integrated circuit scale. This means is achieved by employing double wiring or conductor layers which are electrically connected and designed to permit an extension of the integrated and patterned resistance region while retaining or further reducing the original integrated circuit scale.
In particular, wiring or conductor interconnect means comprising this invention extends the value of an integrated passive electrical component coupled to other passive or active electrical elements in an integrated circuit, the extended value provided without any change in or allowing for a reduction in the scale of integration among the passive or active electrical elements. The interconnect means comprises at least two wiring or conductor layers separated by an insulating layer and laterally extended relative to the electrical elements to a permissible extremity wherein the conductor layers are electrically coupled through the insulating layer whereby a tiered formation of these layers is formed with adjacent tiers thereof being coupled at one elongated extremity thereof. This configuration provides at least one extended wiring length, which is provided to include the desired integrated passive electrical component, whereby the magnitude of the integrated passive electrical component is extended because of the extended conductor length. The interconnect means of this invention is particularly suited for application in an integrated circuit of a memory cell in a high resistance load type static RAM or SRAM, in which case the passive electrical component in the extended wiring length comprises a resistance having an enlarged resistance value due to the designed lateral extension of the wiring layer.
Advantages obtainable through the employment of this invention are:
1. Resistances, or other such passive elements capable of being selectively deposited, diffused or implanted or the like, can be formed in integrated fashion in circuit conductor interconnects between active element domains, for example, in a memory cell configuration, which are extended and, therefore, higher resistance values can be realized without increasing memory cell size. This accomplished by shifting the contact hole relative to the circuit wiring layers so that the longitudinal extent of the resistance element can be enlarged. Thus, the integrated circuit area of a memory cell can be minimized and an enhancement of integration density may be accordingly achieved without any sacrifice of required resistance value.
2. Since a wiring layer capacity will correspondingly be increased by the method of manufacturing of this invention, the static RAM semiconductor device will be strengthened against the so called alpha ray soft error wherein alpha rays penetrate the semiconductor substrate causing undesirable potential fluctuations in the semiconductor device.
3. A satisfactory high resistance value can be readily and easily obtained without unconventional or complex processing techniques.
4. A SRAM semiconductor device will be stable with less consumption current, particularly during the time of standby operation.
Other objects and attainments together with a fuller understanding of the invention will become apparent and appreciated by referring to the following description and claims taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a plan view of an integrated circuit structure of a semiconductor device comprising an embodiment of this invention;
FIG. 1B is a cross sectional view taken along the line 1B--1B of FIG. 1A relative to one embodiment of this invention;
FIG. 1C is a cross sectional view taken along the line 1B--1B of FIG. 1A relative to another embodiment of this invention;
FIGS. 2A, 2B and 2C are cross sectional views of the semiconductor device comprising this invention illustrating in a sequential manner a method of manufacture for the device shown in FIGS. 1A and 1B;
FIG. 3 is a sectional view showing an integrated circuit structure of a portion of a conventional high resistance polycrystalline silicon semiconductor load type memory cell;
FIG. 4 is a schematic circuit diagram of a conventional high resistance polycrystalline silicon load type memory cell shown in part in FIG. 3; and
FIG. 5 is a graphic illustration of the relation between measured high resistance polycrystalline silicon resistance sizes in microns and corresponding resistance values in ohms as measured by the inventor herein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Since like reference numerals denote like components in different views of the drawings relative to both the prior art structure and the structure of the present invention, their description will not be repeated in great detail here.
FIG. 1A is a plan view of a static RAM memory cell comprising an embodiment of this invention and FIG. 1B is a sectional view thereof. As shown in FIG. 1B, a field insulating film 2 is deposited on the surface of semiconductor substrate 1. Elements making up the circuit are electrically isolated by field insulating film 2. A p-type channel stopper domain 3 is provided beneath film 2. A gate insulating film 4 is provided on the surface of each active element domain surrounded by field insulating film 2. A word line, WL, of predetermined form comprises a double layer film of poly silicon film 5 and silicide or polycide film 6 (which form gate electrodes 7, 8) and grounding conductor, SL, (source domain 9), which electrode films are deposited on gate insulating film 4, field insulating film 2 and a portion of formed source domain 9. Grounding conductor, SL, comprises a diffusion layer formed in substrate 1. The n + -type source domain 9 and n + -type drain domain 10 are previously formed in each active element region surrounded by field insulating film 2 in alignment with word line, WL, gate electrodes 7, 8 and grounding conductor, SL. Switching MOSFET's Q 3 , Q 4 comprise word line, WL, source domain 9 and drain domain 10; MOSFET Q1 comprises gate electrode 7, drain domain 10 and source domain 9; and MOSFET Q 2 comprises gate electrode 8, source domain 9 and drain domain 10. Drain domain 10 of MOSFET Q 1 and source domain 9 of MOSFET Q4 are common. MOSFET's Q 1 through Q 4 also contain a LDD (Lightly Doped Drain) structure. Source domain 9 and drain domain 10 are formed by introducing impurities in semiconductor substrate 1 in two separate stages for forming side wall 11 comprising, for example SiO 2 , on the side of word line, WL, and gate electrodes 7, 8.
An interlayer insulating film 12 is provided over MOSFET's Q 1 and Q 2 . A first contact hole 16 is formed in interlayer insulating film 12 and then a first wiring layer 13 comprising n + -type polycrystalline silicon film of predetermined form, illustrated in FIG. 1B, is formed on film 12. Next, a second interlayer insulating film 14 is formed over the first interlayer insulating film 12 over MOSFET's Q 1 and Q 2 . A second contact hole 18 is then formed in the second interlayer insulating film 14 over which is provided a second wiring layer 15 consisting of n + -type polycrystalline silicon regions 15A and 15B of a predetermined form and high resistance polycrystalline silicon region 15C. First wiring layer 13 and second wiring layer 15 are electrically connected through second contact hole 18. Accordingly, second wiring layer 15 is connected to source domain 9 of MOSFET's Q 3 and Q 4 via second contact hole 18 provided in second insulating film 14 and adjacent the end of double film 5, 6 comprising electrode 7.
The sheet resistance for n+-type polycrystalline silicon regions 15A and 15B will be, for example, about 150 ohms per square or smaller for a second wiring layer 15 having a thickness of about 100 nm.
Under present practice, relative sizes of the high resistance polycrystalline silicon resistances R 1 , R 2 of regions 15C are determined according to the interval spacing between the first contact hole 16 and power source V DD as exemplified in FIG. 3. However, in the present invention, high resistance polycrystalline silicon resistances R 1 , R 2 are formed through first wiring layer 13 to an extended second wiring layer 15, as illustrated in FIG. 1B, thereby determining the extent and, therefore, the value of resistances R 1 , R 2 according to an interval spacing between the position of second contact hole 18 and power source V DD . Accordingly, the relative sizes of resistances R 1 , R 2 can be increased by the additional interval spacing between first contact hole 16 and second contact hole 18 without increasing the length or size of the memory cell, i.e., without increasing the length between MOSFET's Q 1 and Q 3 , while achieving a required high resistance value for both resistances R 1 , R 2 . The increase in resistance value without change to the memory cell configuration is of significant importance in the light of the requirement for a refined construction which is realized by the approach of this invention. This approach leads to a decrease in current consumption of the static RAM during its standby mode. Also, since the area of the memory cell can be minimized while retaining large resistance values for R 1 and R 2 , an increase in integration density of the memory chip is therefore possible.
A third interlayer insulating film 17, for example a PSG film, is then deposited over second wiring layer 15 and resistances R 1 , R 2 . Then, data lines DL and bar DL, each comprising an aluminum film, are deposited on interlayer insulating film 17. These data lines DL and bar DL are then connected respectively to drain domains 10 of MOSFET Q 3 and MOSFET Q 4 via contact holes 21 provided in gate insulating film 4, interlayer insulating film 12, second interlayer insulating film 14, and third interlayer insulating film 17.
Reference is now made to FIG. 1C comprising another embodiment of this invention. The FIG. 1C embodiment is substantially identical to the FIG. 1B embodiment and, therefore, like reference numerals denote the same components in each embodiment and the description for FIG. 1B is equally applicable to FIG. 1C. In FIG. 1C, however, first contact hole 16 is extended through insulating layer 12 so that the subsequent deposit of first wiring layer 13 is extended past the ends of electrode layers 5, 6 to be in direct surface contact with source domain 9, as indicated at 13A. In this manner, metal layer 13 is in direct contact with a surface portion of layer 6 as well as edges of both layers 5, 6, as indicated at 7A, in addition to direct contact at 13A with source domain 9. In the FIG. 1B embodiment, metal layer 13 is in direct contact with the surface of layer 6 and makes electrical contact to source domain 9 through electrode layers 5, 6.
Reference is now made to a fabrication process for the static RAM disclosed in FIGS. 1A and 1B. After MOSFET's Q 1 through Q 4 , word line, WL, grounding conductor, SL, and other components have been formed, as illustrated in FIG. 2A, insulating film 12 is deposited over the foregoing after which first contact hole 16 is formed in film 12 by photoetching. Then, polycrystalline silicon film 19 is formed over the surface, for example, to a thickness of 100 nm or so, via chemical vapor deposition. Next, an impurity, such as P, As or the like, is diffused into film 19 followed by an ion implantation to achieve a low resistance in the film. In the case of ion implantation of a P impurity, for example, an ion implant of about 30 kev with a dose rate at about 6×10 15 cm -2 is suitable.
Next, as illustrated in FIG. 2B, polycrystalline silicon film 19 is patterned in a predetermined form through selective photoetching. The patterning is in the direction of word line, WL, (FIG. 1A) from first contact hole 16. Next, second interlayer insulating film 14 is formed over the surface and second contact hole 18 is formed through film 14 by photoetching. Second contact hole 18 is formed, not over first contact hole 16, but laterally in the direction of word line, WL, and laterally beyond the position of hole 16 so that the length and, therefore, correspondingly the resistance values of R 1 and R 2 can be increased.
Next, as shown in FIG. 2C, an intrinsic polycrystalline silicon film of relative thin dimension, for example about 50 nm or so, is formed on second interlayer insulating film 14 via chemical vapor deposition. Next, a resist mask layer is provided on a portion 15C of the intrinsic polycrystalline silicon film 14, which will correspond to resistances R 1 , R 2 to be subsequently formed. This is followed with a diffusion of P or As and ion implantation in the exposed regions 15A and 15B thereby maintaining portion 15C of film 14, protected by the resist mask layer, at its existing high resistance value while those portions 15A and 15B exposed to the diffusion and ion implant process are at a low resistance value. Since film 14 is thinner than first wiring layer 13, it is desirable that energy employed for ion implantation of the impurity be of lower value than employed in connection with the treatment of film 19.
After the resist mask layer is removed, polycrystalline silicon layers 20 (FIG. 1A) are patterned into desired form via photoetching resulting in a wiring or conductor layer 15 of predefined dimensions and including conductive regions 15A and 15B and high resistance regions 15C, comprising R 1 and R 2 , with R 2 being visible in FIG. 2C. Third interlayer insulating film 17, contact hole 21 and data lines DL and bar DL are thereafter formed, as depicted in FIGS. 1A and 1B, to complete the fabrication of the static RAM. Thus, according to the manufacturing process described above, a static RAM with minimized standby current, I DDS , and stable operating characteristics is achieved through a fairly simple fabrication process.
While the invention has been described in conjunction with two embodiments, it is evident to those skilled in the art that many alternatives, modifications, applications and variations will be apparent in light of the foregoing description. For example, the concept of this invention is not limited to passive components in the form of resistances in a SRAM circuit but also is extendable to other passive components capable of being deposited, such as capacitors and inductors, as well as extendable to other types of IC applications.
Also, a high fusing point metallic silicide film may be provided for first wiring layer 13, instead of a polycrystalline silicon film, to provide for the low resistance value portions of the film. In this case, a sheet resistance value of first wiring layer 13 may be decreased to approximately 15 ohms per square or below. As a result, a memory signal delay due to excessive wiring resistance may be prevented or substantially reduced. Since the resistance value is low, the use of this silicide film may also be employed as a wiring layer relative to input/output circuits on an IC chip.
Furthermore, if the high resistance polycrystalline silicon resistances R 1 , R 2 are formed in second wiring layer 15, for example, so as to cross over an end of first wiring layer 13, their crossing will naturally occur at different levels in the circuit. Therefore, the sizes of R 1 and R 2 may be substantially increased due to the length of increase provided in the intrinsic polycrystalline film deposited between wiring levels 13 and 15. As a result, the resistance values for R 1 and R 2 may be further increased without any change in the memory cell scale.
Lastly, if first wiring layer 13 or a portion thereof is constructed of an intrinsic silicon film along with all or a portion of second wiring layer 15, then two high resistances connected in series may be realized thereby providing means for obtaining very high resistance values in the IC structure. With respect to the forgoing, it can, therefore, be appreciated that these resistance values may be varied by adding series resistances either laterally in horizontal layers or regions of a semiconductor device or in vertical layers or regions transversely of the deposited layers of the semiconductor device. Also, it can be realized that a serpentine pattern of series resistances included in longitudinally extended conductors separated by insulating layers with conductor ends in adjacent conductors coupled via contact opening in the insulating layer therebetween, which opening is prepared at one extremity of such adjacent conductors.
Thus, the invention described herein is intended to embrace all such alternatives, modifications, applications and variations as fall within the spirit and scope of the appended claims. | A wiring or conductor structure for an integrated circuit structure of a semiconductor device is designed to provide for extended values in integrated passive components, for example, resistance values in a memory cell of a high resistance load type static RAM. Extended values of high resistance polycrystalline silicon resistances formed in conductor films are achieved by effectively increasing the length of the films and, therefore, the regions of resistance without changing or increasing the size or scale of the semiconductor device. This is accomplished by employing double wiring or conductor layers which are electrically connected permitting a lateral extension of the integrated and patterned resistance region in at least one of the wiring layers while retaining or further reducing the integration scale of the active and passive components comprising the integrated circuit structure. | 7 |
BACKGROUND
[0001] The present invention generally relates to the field of Design Automation of semiconductor VLSI chips, and more particularly, to a method and a system providing an efficient statistical timing analysis of cycle time independent tests.
[0002] An objective of a conventional statistical static timing analysis (SSTA) is to prevent circuit limited yield (CLY) losses by accounting the effects of parametric variability upon switching time distributions of various signals within a digital circuit. SSTA can be performed at a transistor level or at a gate level, using pre-characterized library elements including those at higher levels of abstraction for complex hierarchical chips.
[0003] SSTA algorithms are known to operate by way of a first levelizing the logic structure, and breaking any loops in order to create a directed acyclic graph (timing graph). Modern designs can often contain millions of placeable objects, with corresponding timing graphs having millions or tens of millions of nodes. For each node, a corresponding arrival time (AT), transition rate (slew), and required arrival time (RAT) are computed for both rising and falling transitions as well early and late mode analysis. Each value can be represented in general as a distribution, i.e., using a first-order canonical form, wherein timing quantities are represented as functions of underlying sources of variation, as described e.g., in U.S. Pat. No. 7,428,716 to Visweswariah, of common assignee. The arrival time (AT) distribution represents the latest or earliest time at which a signal can transition due to the entire upstream fan-in cone. Similarly, the required arrival time (RAT) distribution represents the latest or earliest time at which a signal must transition due to timing constraints in the entire downstream fan-out cone.
[0004] The ATs are propagated forward in a levelized manner, starting from the design primary input asserted (i.e., user-specified) arrival times, and ending at either the primary output ports or the intermediate storage elements. In single fan-in cases, AT sink node=AT source node+delay from source to sink.
[0005] Whenever multiple signals merge, each fan-in contributes a potential arrival time computed as AT sink (potential)=AT source+delay, making it possible for the maximum (late mode) or minimum (early mode) of all potential arrival times to be statistically computed at the sink node. Typically, an exact delay function for an edge in a timing graph is not known, but instead only the range of possible delay functions can be determined between some minimum delay and a maximum delay. In this case, maximum delay functions are used to compute the late mode arrival times and minimum delay functions used to compute the early mode arrival times.
[0006] A timing test (e.g., setup or a hold check) involves a comparison of arrival times in order to determine if the proper ordering relationships between the corresponding signals are satisfied. Such a comparison of AT values produces a quantity known as slack, which when positive in sign indicates that the timing test has been satisfied (and the margin thereof), whereas a negative value indicates a failing test and potential problem.
[0007] Timing tests can be broadly categorized as either clock cycle time dependent or cycle time independent. Cycle time dependent tests are those whose slack is computed as a function of clock cycle time(s). By contrast, cycle time independent tests are those wherein the computed slack value is invariant to underlying clock cycle time(s). Typically, but not always, setup tests are cycle time dependent, as a full clock cycle (or the greatest common divisor of clock cycles) is allowed for an arrival time to propagate from launching to a receiving latch, and therefore, the slack depends on the cycle time(s) of the launch and the capture clocks. Similarly, it is typical for hold tests to be cycle time independent. The aforementioned, however, does not always hold true for setup and hold tests, as various adjusts can be present in the timing graph. For example, in the case of a user specified timing adjust (e.g., equal to a full clock cycle, or a greatest common divisor [GCD] of clock cycles), a setup test can end up becoming a cycle time independent test, and/or a hold test can become cycle time dependent.
[0008] In the case of some high-performance digital integrated circuits, at-speed screening is performed, and manufactured products are binned into multiple frequency categories. In such circumstances, during the digital implementation phase, timing engineers can be particularly interested in ensuring that parametric variation does not result in a circuit limited yield (CLY) loss for cycle time independent timing tests. As such, CLY issues can present chip-kill problems that are present regardless of the lowering of the clock frequency. On the other hand, when such screening and binning manufactured products by frequency is possible, the timing engineers can be willing to accept the possibility of CLY loss at a particular target cycle time for cycle time dependent timing tests since the underlying circuits can be able to operate correctly at one of the lower clock frequency bins. In the above situation, it is often the case that timing engineers desire a means to perform SSTA and report the results for cycle time independent tests only.
[0009] One prior technique for performing SSTA analysis of cycle time independent tests has traditionally involved a first propagation of full timing data on the entire timing graph (i.e., propagating early and late timing values regardless of whether a value is needed in a downstream cycle time independent test), using an inflated cycle time. The purpose of the inflated cycle time is to move the cycle time dependent tests to a positive slack value, such that only tests which are frequency independent can show up as a negative slack requiring attention from a SSTA closure perspective. However, there are inherent inefficiencies with the prior art when using an inflated cycle time. Most importantly, a full AT and RAT propagation is still required throughout the entire design, regardless of whether a timing quantity is of interest, i.e., needed at a timing test which is frequency independent. This leads to an excessive amount of wasted calculation and an increasing runtime which negatively impacts designer productivity.
[0010] In another prior art technique, SSTA is performed on a timing graph (propagating early and late timing values regardless of whether a value is needed in a downstream test), and is followed by generating reports which are filtered based on the test type. For example, using such prior art methods, a timing engineer can select only report hold tests (and exclude setup tests) in order to determine whether there are any violations among cycle time independent tests. The use of filtering of reporting, however, can miss cycle time independent setup cases (such as those involving a user specified timing adjust, as previously described), and can report hold tests which are cycle time independent (e.g., similarly, in a case involving a user specified timing adjust). Furthermore, filtering reports suffers from the same problem of wasted calculations as described above with respect to the prior art method of inflating clock cycle time.
[0011] In summary, in a high performance chip design there is a desire to perform statistical timing for the purpose of analyzing frequency independent tests, whereas frequency dependent tests are handled by a separate “nominal” timing run. This differentiation is presently supported by performing a statistical timing run with cycle time uplift such that the cycle time dependent tests have large slack values. The cycle time uplift approach is both cumbersome and leads to wasteful calculation of many statistical timing quantities that are not needed (when such quantities only feed the frequency dependent tests).
[0012] Accordingly, there is a need to provide a method and a system capable to achieve an efficient statistical timing analysis of cycle time independent tests.
SUMMARY
[0013] In an embodiment, a method and a system are provided to perform a statistical timing analysis wherein timing quantities feeding cycle time dependent tests are identified and filtered using a fast forward and backward propagation marking steps, followed by the propagation of statistical timing only where a value is needed for a downstream cycle time independent test.
[0014] In an embodiment, a method is provided to eliminate wasteful calculations, limiting timing calculations and performing significant runtime savings to reduce the number of instances where a full statistical propagation is performed, when it is compared to a method involving cycle time uplift.
[0015] In an embodiment, a method of statistical static timing analysis of a digital electronic design includes: a) using a computer, propagating from at least one signal source to at least one timing test at least one signal label, the at last one signal label including at least one of i) at least one signal source identifier, and ii) a signal path cycle adjust information; b) determining at the timing test which of the signal label values at each input of the timing test are needed to compute a selected timing test; c) propagating back from the timing test value needed flags; d) propagating and computing timing data only for the signal labels where the value needed flag is true.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The accompanying drawings, which are incorporated in and which constitute part of the specification, illustrate the presently preferred embodiments of the invention which, together with the general description given above and the detailed description of the preferred embodiments given below serve to explain the principles of the invention.
[0017] FIG. 1 shows a flowchart illustrating an embodiment of the present invention.
[0018] FIG. 2 is an exemplary circuit used to illustrate an embodiment of the present invention.
[0019] FIG. 3 depicts a forward-levelized timing graph applied to the aforementioned exemplary circuit.
[0020] FIG. 4 shows a table listing nodes of the aforementioned timing graph, and illustrating the propagation from a signal source to a timing comparison having a signal label, the signal label including at least one signal source identifier, and signal path cycle adjust information.
[0021] FIG. 5 shows a table listing the nodes of the aforementioned timing graph, illustrating the propagation back from the timing comparisons needed signal labels.
DETAILED DESCRIPTION
[0022] The present invention and various features, aspects and advantages thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description.
GLOSSARY OF TERMS
[0023] In order to clarify the meaning of terms recited in the disclosure, a glossary of the terms as defined is added herein below:
[0024] Adjust: Modification of a timing quantity typically specified by the application of a timing constraint.
[0025] Segment adjust: A particular type of adjust applied to values propagating through a particular edge of the timing graph.
[0026] Cumulative adjust: Sum total of adjusts along a path.
[0027] Forward propagation: Propagation of values along the direction of directed edges in a timing graph.
[0028] Backward propagation: Propagation of values in the direction opposite to directed edges in a timing graph (e.g., propagation from sink node to a source node).
[0029] Signal source: A node within a timing graph containing a user-specified arrival time.
[0030] Signal source identifier: Phase tag or other flag indicating the signal source of a given arrival time or slew value.
[0031] Referring to FIG. 1 , an embodiment of the disclosure is illustrated, wherein Step 101 begins with forward propagating from one or more signal sources to one or more timing tests a signal label consisting of at least one signal source identifier, and corresponding cumulative adjust information.
[0032] In Step 102 , wherein at one or more timing test, a determination is made of which signal labels are required to perform the timing test.
[0033] In Step 103 , the determination of the signal labels required to perform a timing test is followed by propagating back from at least one timing test value needed flags for signal labels.
[0034] In Step 104 , the propagation and computation of timing data occurs only for the propagated signal labels where a value is necessitated.
[0035] Referring now to FIG. 2 , a non-limiting simple exemplary circuit diagram is shown to illustrate an application of an embodiment. In the simple exemplary illustrative circuit, early and late mode arrival times are assumed to be asserted at the input “A” of box 201 . For the purpose of clarity, both the output L 2 of box 205 and the input D box 203 are left as open circuits. Box 201 and box 202 are buffers that propagate a clock signal to clock inputs of box 203 and box 205 intending to illustrate edge-sensitive storage elements (e.g., flip-flops). Similarly, box 204 depicts a buffer propagating a data signal from the L 2 output of box 203 to D input of box 205 .
[0036] A user-specified full clock period adjust at the Z output of box 204 is shown (in general, such adjust values can be stored on a node, an edge, a path, or any combination thereof, in which an embodiment accommodates all of such forms). For the purpose of simplicity, a full clock period adjust is chosen in the illustrative example, although in an embodiment it can be applied in the presence of arbitrary timing adjusts. The value of individual adjusts need not to be exactly equal to the clock period, e.g., multiple adjusts can accumulate along a path that taken together, add to the greatest common divisor GCD of the launch and capture clock cycles.
[0037] Referring to FIG. 3 , a forward levelized timing graph representation of the above simple non-limiting illustrative circuit is shown. Such a timing graph is typically constructed ahead of the propagating timing information, although it can also occur in concert with the propagation of any timing flags or values. Multiple timing tests (i.e., setup and hold) are depicted between input box 205 /D and box 205 /C.
[0038] Referring to FIG. 4 , the resulting signal labels are obtained when applying the aforementioned Step 101 of FIG. 1 previously described, as applied to the timing graph of the exemplary circuit. In a simple non-limiting illustration it as assumed that the asserted arrival time at box 201 /A is cycle time independent. Therefore, a value of zero cycle adjust propagates forward from box 201 /A. In an embodiment, all general cases are asserted where arrival times can themselves be cycle time dependent and consequently, a non-zero cycle adjust value can immediately begin propagating forward from the asserted signal source(s). The value of a zero total adjust continues to propagate forward until a user-specified timing adjust of one clock cycle is encountered at box 204 /Z. It is worth noting that adjusts are recorded for both the early and the late mode transitions. For the purpose of simplicity, in the non-limiting example, the same user-specified adjust value is shown to be applied in both the early and late modes, where distinctions between the rise and fall transitions have been omitted. An embodiment of the disclosure can accommodate all the general cases where unique adjust values are propagated for early and late modes, and where unique adjusts are propagated for the rise and the fall transitions thereof. Furthermore, in the simple exemplary illustration, for the purpose of determining a signal source label, a single synchronous clock domain referenced as “C” is assumed. Nonetheless, an embodiment of the present invention accommodates all the generalizations of signal source labels, including propagation of multiple such labels, e.g., in order to store timing values unique to multiple synchronous clock domains per graph node, unique labels for the early versus the late mode and unique labels for rising and falling transitions thereof.
[0039] For further illustration, in a non-limiting example shown in FIG. 4 it is assumed that the signal labels are forward propagated in a breadth-first forward propagated fashion. There are multiple ways of forward the propagating information in the levelized graph, and an embodiment accommodates all possible forward propagation methods, including demand-driven (i.e., propagation to a specific node of interest), and all combinations of depth and breadth-first traversal. During the propagation of signal labels, it is possible to encounter a graph node which has multiple incoming edges (e.g., FIG. 3 box 203 /L 2 ). When multiple incoming edges are present, the union of signal labels is retained.
[0040] FIG. 5 illustrates the application of Steps 102 and 103 of FIG. 1 previously described, to the timing graph of the exemplary circuit. In the present example, FIG. 1 Step 102 applies to nodes box 205 /D and box 205 /C that are involved in both setup and hold tests with respect to each other.
[0041] Focusing first on the setup test case, the general slack equation for a setup test is:
[0000] SLACK=EARLY CLOCK AT−LATE DATA AT+CYCLE ADJUST.
[0042] Applying to the aforementioned nodes,
[0000] SLACK=EARLY AT ( 205 /C)−LATE AT ( 205 /D)+CYCLE ADJUST (ONE CLOCK PERIOD)
[0043] Referring back to FIG. 4 , it has been determined that box 205 /D has a cumulative adjust of −1 clock period, whereas box 205 /C has zero cumulative adjust. Plugging adjusts in the aforementioned setup slack equation, it is evident that the setup test between box 205 /D and box 205 /C is a cycle time independent (since adjust - 1 clock period for box 205 /D cancels out the CYCLE ADJUST+1 clock period in the setup slack equation above). Therefore, the LATE mode AT value for box 205 /D is required for a cycle time independent test (e.g., for the setup test against box 205 /C), and the same can be for the EARLY mode AT value for box 205 /C.
[0044] Focusing next on a hold test case, the general slack equation for the hold test is
[0000] SLACK=EARLY DATA AT−LATE CLOCK.
[0045] Applying to the aforementioned nodes,
[0000] SLACK=EARLY AT(( 205 /D)−LATE AT ( 205 /C).
[0046] Referring back to FIG. 4 , it is determined that box 205 /D has a cumulative adjust −1 cycle, whereas box 205 /C has zero cumulative adjust. Plugging adjusts to the hold slack equation above, it is evident that the hold test between box 205 /D and box 205 /C is cycle time dependent (i.e., the slack will vary as a function of clock cycle time due to the fact that the EARLY AT for box 205 /D has a cycle time dependent adjust). Therefore, the EARLY mode AT value for box 205 /D is not required for a cycle time independent test (i.e., the only test that the EARLY mode AT for box 205 /D is involved with is a hold test, and as described previously, the particular hold test is cycle time dependent). The same applies to the LATE mode AT value for box 205 /C.
[0047] Still referring back to FIG. 1 , Step 103 applies to all predecessor nodes of box 205 /D and 205 /C by back-propagating “AT needed for a downstream cycle time independent test” values (abbreviated “AT needed” hereinafter), resulting in a remainder of the values shown in FIG. 5 . Generally, for any node having at least one outgoing edge, test edge, the “AT needed” flag is set to true if at least one outgoing edge propagates an “AT needed” value of true, or at least one test contributes an “AT needed” value of true, in accordance with the embodiment related to FIG. 1 , Step 102 . Otherwise, if no outgoing edge propagates an “AT needed” value true, and neither does any test, the “AT needed” flag is set false, as is the case for box 205 /L 2 in the aforementioned example. If multiple signal labels propagate in accordance with FIG. 1 Step 101 , then each signal label is assigned its own “AT needed” flag, in accordance with FIG. 1 Step 103 and the aforementioned description.
[0048] It should be noted that while the example above referred to specific instances of setup and hold tests, the present invention accommodates all timing tests, including same mode tests, domino tests, tests involving multiple clock domains, tests involving user specified constraints on the alignment of launch and capture edges, user-specified tests, domino tests, tests within abstracted library elements, asserted arrival time constraints, point to point delay constraints, skew tests, window tests, and any combination thereof. Furthermore, while the example above focused on indentifying cycle time independent tests for statistical timing analysis, the present invention also accommodates the identification of cycle time independent tests performed during product stress testing, as well as for identifying cycle time dependent tests. And furthermore, in cases involving multiple synchronous clock domains, the present invention also accommodates excluding tests between pairs of non-synchronous clocks, and marking corresponding AT values as “value needed” false where non-synchronous relationships disable a timing test.
[0049] Additionally, with reference to the example above, timing data (including statistical AT, slew and delay values) are propagated and computed only for those signal identifiers for which an “AT needed” flag is set to true.
[0050] Moreover, the aforementioned steps can be performed in an incremental fashion, i.e., causing signal labels and value needed flags to be updated in response to a design change, after an initial timing propagation has occurred. For example, if a new adjust is added, cumulative adjust values can be updated, which in turn may cause “value needed” flags to change based on new cumulative adjusts propagating to tests. Similarly, the introduction of new test points may result in additional “value needed” propagations. And similarly, changes in timing graph topology can cause changes in both signal labels and “value needed” flags. Such incremental propagation may occur through well-known means, such as the use of delta lists and queues, which can be further processed using well-known techniques of level-limiting to minimize recalculation efforts.
[0051] Finally, the present invention can be realized in hardware, software, or a combination of hardware and software. The present invention can further be realized in a centralized fashion in one computer system or in a distributed fashion where different elements are spread across several interconnected computer systems. Any kind of computer system - or other apparatus adapted for carrying out the methods described herein—is suitable. A typical combination of hardware and software could be a general purpose computer system with a computer program that, when being loaded and executed, controls the computer system such that it carries out the methods described herein.
[0052] Embodiments of the disclosure can be embedded in a computer program product, which includes all the features enabling the implementation of the methods described herein, and which—when loaded in a computer system—is able to carry out these methods.
[0053] Computer program means or computer program in the present context mean any expression, in any language, code or notation, of a set of instructions intended to cause a system having an information processing capability to perform a particular function either directly or after conversion to another language, code or notation and/or reproduction in a different material form.
[0054] While the present invention has been particularly described in conjunction of a simple illustrative embodiment, it is to be understood that one of ordinary skill in the art can extend and apply this invention in many obvious ways. In the embodiments described herein, for purposes of clarity, rising and falling timing quantities were not differentiated, but one of ordinary skill in the art could apply the present invention to a situation with different rising and falling delays, slews, ATs and RATs. Embodiments of the invention apply to any type of static timing analysis, including but are not limited to both deterministic (e.g., single corner) and statistical timing of gate-level circuits, transistor-level circuits, hierarchical circuits, circuits with combinational logic, circuits with sequential logic, timing in the presence of coupling noise, timing in the presence of multiple-input switching, timing in the presence of arbitrary timing tests such as setup, hold, end-of-cycle, pulse width, clock gating and loop-cut tests, and timing in the presence of multiple clock domains. It is also evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the present description.
[0055] It is therefore contemplated that the appended claims will embrace any such alternatives, modifications and variations as falling within the true scope and spirit of the present invention. | A system performing selected timing comparisons in a digital electronic design includes propagating from signal sources to timing comparisons of one or multiple signal labels. The signal label includes signal source identifiers and signal path cycle adjust information. Timing comparisons are determined in which signal label values at each input of the timing comparison are required to compute the selected timing comparisons. The propagation back from the timing comparisons are needed signal labels, followed by the propagation and computing timing data from the signal source applied to the propagated signal labels corresponding to the required signal labels. | 6 |
FIELD AND BACKGROUND OF THE INVENTION
[0001] The present invention is a standoff force multiplier weapon, relating to distance control, enemy neutralization, and casualty reduction.
[0002] When the U.S. military goes to war, it relies on sophisticated and efficient weaponry to defeat the enemy. Yet, no matter how sophisticated the weapons, an all-volunteer military cannot absorb large numbers of causalities. In an effort to reduce the number of causalities suffered by our troops, modern weapons are designed to deliver payloads from great distances with uncanny accuracy. Although these standoff weapon systems are intended to eliminate close infighting; pitch battles and firefights remain an integral part of military planning and tactics.
[0003] Close infighting causes causalities because the ideal weapon balance has not been introduced into battle with the intention of neutralizing the enemy; rendering hiding useless; and eliminating counter fire. Many casualties occur when the enemy takes cover and returns fire. In fact, the best way to stop an enemy is to prevent them from using their weapons. If the enemy is deprived of the ability to return fire, the probability for causalities becomes near zero. The solution is to overwhelm the enemy with a firewall of pinpoint airburst detonations at the onset of battle and continue until the enemy is destroyed. The radius of the airburst detonations will devastate both the exposed and concealed. But, the firepower must be instantaneous, overwhelming and totally destructive. Fortunately, a new innovative weapon called the CMDP can accomplish both tasks simultaneously. The CMDP or Cruise Munitions Detonator Projectile is a weapon created to travel a predetermined distance to the enemy and detonate with pinpoint accuracy anywhere in the enemy's vicinity or range. The detonation of a single shell will suppress enemy fire and neutralized them at the same time.
[0004] What makes the CMDP so deadly is: a) the distance to the target is determined by a range dial selector, laser range finder or radar, b) firing the gun and downloading range data into the CMDP's memory is done simultaneously, and c) the CMDP travels the distance to the target along a straight path and detonates. It can also be modified to detonate on impact.
[0005] The CMDP application is not only limited to ground forces, it can also be used on aircraft; or tanks; in military camps; and on ships. CMDPs can be used with a modified grenade launcher to substitute for Claymore mines if motion detector sensors (systems) are positioned around the perimeter of a field camp. Aircraft, such as jets or helicopters equipped with the CMDP (along with an automatic tracking and aiming system) could defend themselves against enemy aircraft: SAMS, shoulder launched missiles and air-to-air missiles; by firing and detonating a CMDP or (CMDPs) at intersecting points along the object's fight path. The target will be destroyed. Current aircraft equipped with detection devices only warn of impending dangers, using flare and chaff dispensing systems to redirect threats, in order to evade them. Evading works sometimes, but the threat must be eliminated altogether to have a zero causality equation loss. AAA threats against attacking aircraft over a target area can be controlled and neutralized using the CMDP. Aircraft like the B52 bomber and A-10 Warthog could operate with impunity over targets while using the CMDP to destroy heat seeking missiles. And, if an aircraft lands in enemy territory, an undamaged CMDP/system has the potential to defend the aircraft and those on board.
[0006] Unlike defense systems aboard ships where bullets must hit targets, the CMDP simply detonates in the path of the target. As described, the CMDP can be used as a defensive or offensive weapon.
[0007] A Tank's main gun is another weapon platform that is known for its destructive power, but it too, has weaknesses against air-to-surface and shoulder launched missiles, that cause great causalities. Faced with immeasurable odds, multiple CMDPs fired from tanks can destroy hundreds, even thousands of enemy troops. And, if equipped with an automatic tracking and aiming system, it can defend itself against shoulder launched missiles and air-to-surface missiles by firing and detonating a CMDP or CMDPs at intersecting points along the object's fight path.
[0008] Mortar attacks make military camps unsafe, resulting in loss of life and property. Lives can be saved with near zero percent causality if software controlled tracking systems equipped with CMDPs are used to defend against the incoming mortar. The gun systems can be daisy-chained to secure the entire camp.
[0009] When Special Ops, patrol or recon units are in a jam and pinned down, they call in fire support to neutralize the enemy. If the action is too close; firing on the target is not an option. Without accurate firepower there will be no escape, resulting in inevitable causalities. These situations can be avoided if the units are armed with CMDPs, a modified grenade launcher equipped with a range dialer, laser range finder and thermo heat sensor. US forces should be confident that they have instantaneous and overwhelming firepower with them when fighting their way into and out of situations. The CMDP allows smaller forces to strategically neutralize larger forces with devastating effect.
[0010] The CMDP is the optimum weapon for ground troops to engage snipers hiding on mountain ridges, in trees, rooftops, or building openings used for cover. It can also neutralize reinforced bunkers or weapons platforms. As previously stated, the CMDP is launched from a gun using a combination of a range selector; laser range finder, thermo sensor and radar to determine the distance to a target and to download the data into it. Adding or subtracting a quantity to or from the input data will achieve a desired distance. Aiming at a target is accomplished with a stand-alone gun or software controlled tracking system. The CMDP distance to the target is very accurate and is limited only by its range.
SUMMARY OF THE INVENTION
[0011] According to the present invention there is provided a CMDP for neutralizing large enemy ground forces and missiles while defending against enemy moving objects. The CMDP includes a data link and memory for downloading distance target information; a safe distance arming circuit; a pressure switch for initializing digital counting; and a comparator circuitry that determines the detonation time.
[0012] According to one embodiment of the present invention, the CMDP is a shell requiring data input.
[0013] According to another embodiment of the present invention, the CMDP is a shell. Preferably the shell is launched from a gun type system, tank or modified grenade launcher gun.
[0014] According to a preferred embodiment of the present invention, the CMDP is a projectile. Preferably the projectile is launched to predetermined distances and then detonates.
[0015] According to still further features in the described preferred embodiment, the projectile is a munitions.
[0016] According to another feature in the described preferred embodiment, the projectile includes electronic circuitry for launch detection.
[0017] According to still further features in the described preferred embodiment, the projectile includes an electronic safety circuit to arm the CMDP for detonation after clearing a safety zone.
[0018] According to the described preferred embodiment, the projectile includes electronic circuitry for downloading range data into memory for targeting range.
[0019] According to the described preferred embodiment, the projectile includes electronic circuitry for counter comparison detection to accurately determine when to detonate the munitions.
[0020] According to a preferred embodiment of the present invention, the CMDP further includes electronic circuitry to detonate the projectile.
[0021] According to a preferred embodiment of the present invention, the CMDP can be used to defend aircraft, warships and military camps against incoming missiles, mortars and enemy aircraft.
[0022] According to a preferred embodiment of the present invention, the CMDP can be used to defend aircraft and passengers against enemy forces after forced landings.
[0023] According to a preferred embodiment of the present invention, the CMDP can be used to neutralize distant targets.
[0024] According to a preferred embodiment of the present invention, the CMDP can be used to reduce and eliminate casualties.
[0025] According to a preferred embodiment of the present invention, the CMDP can be used to keep the enemy at bay.
[0026] According to a preferred embodiment of the present invention, the CMDP can be used to neutralize large enemy forces.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The invention is herein described by way of: an illustrated modified shell shown in FIG. 1 and the tested CMD schematic circuit shown in FIG. 3 :
[0028] FIG. 1 , is a diagrammatic cross-section of a projectile according to one embodiment of the present invention wherein the projectile is a modified shell;
[0029] FIG. 1 e , is a cross-section diagram showing the pressure switch in said projectile according to one embodiment of the preferred invention;
[0030] FIG. 1 i , is a diagrammatic cross-section showing the Cruise Munitions Detonator (CMD) location in the projectile according to one embodiment of the preferred invention;
[0031] FIG. 2 , is a diagram of the modified shell base plate according to an embodiment of the preferred invention;
[0032] FIG. 2A , is a diagram of the seal and metal data ring according to one embodiment of the preferred invention;
[0033] FIG. 2B , is a diagram of the data wire feeding into the seal according to one embodiment of the preferred invention;
[0034] FIG. 3 , is the CMD circuit schematic according to one embodiment containing the pressure switch; memory data storage circuitry; counting and comparator circuitry; safe distance circuitry, and detonation enabling circuitry;
[0035] FIG. 4 , is a diagram of a tank according to one embodiment; firing CMDPs into the mist of a large enemy force.
[0036] FIG. 5 , is a diagram of CMDPs being fired into a reinforced bunker on a mountaintop and detonating in mid-air according to another embodiment of the preferred invention;
[0037] FIG. 6 , is a diagram of CMDPs being fired according to one embodiment taking out enemy positions concealed along a mountaintop ridge;
[0038] FIG. 7 , is a diagram of a CMDP according to one embodiment, detonating over the enemy in a crater;
[0039] FIG. 8 , is a diagram of a helicopter according to one embodiment, defending against shoulder launched missiles using CMDPs;
[0040] FIG. 9 , is a diagram of multi CMDPs according to one embodiment, defending against larger enemy formations;
[0041] FIG. 10 a & 10 b , are diagrams of the Munitions Timer Input & Output Timing Chart according to one embodiment of the preferred invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0042] The present invention pertains to a projectile that detonates in mid-air after traveling along a programmed flight path and predetermined distance. The flight path of the projectile is determined by the operator or guidance system and is maintained in flight by its initial velocity. Specifically, the present invention can be used to neutralize larger enemy forces; combatants hiding behind objects or strategically placed combatants on the battlefield. The CMDP can also be fired from any aircraft or helicopter as an anti SAMS device, anti shoulder rocket device or anti air-to-air missile device. It would work well in neutralizing incoming mortar rounds in mid-air before they ever strike the ground. It can be deployed on aircraft as an excellent anti dog fighting weapon. Operating as an anti projectile eliminator, each system will use a radar or laser tracking system: electronic distance measuring, and calculating software (firmware) and an aiming device. The CMDP can be used to destroy moving or stationary targets. The CMDP allows one tank to fully engage larger size troop threats with efficient use of munitions, which means that the CMDP is a force multiplier.
Modified Shell
[0043] For the purpose of the present description and appended claims, by way of modified shell design (example only):
[0044] A surface groove is symmetrically cut into and around the base plate as shown in FIG. 2 , and a small hole is drilled through the base plate within the path of the groove. The groove is deep enough to overlay the seal and metal data ring and remain flush with the surface of the base plate. FIG. 2A , shows a small AWG insulated wire attached to the stem of the data ring. The wire is aligned with the seal and pushed through the opening in the seal and into the shell as shown in FIG. 2B . The seal insulates the metal data ring from the shell's metal base plate. An insulated ground wire is soldered and insulated onto the inside of the shell and terminates into an insulated plug along with the data wire inside the shell see FIG. 1 b . The shell is then filled to a predetermined level with propellant (not shown) FIG. 1 g . A thin curve plate in FIG. 1 f , is placed over the propellant with the plug on top. An insulation material or foam is than used to insulate the plug from the other components (not shown). The pressure switch rests on top of a thin plate and makes contact as shown in FIG. 1 e.
[0045] The base plate of a shell is modified (modified shell) to allow data to be transferred to the CMDP's memory. The CMDP's internal wires terminate into plug PI, as shown in FIG. 1 d.
[0046] A cylinder is fastened to the center of the CMDP circuitry housing. The cylinder houses the pressure switch wires and data link wire. The detonator (not shown) is placed in the cylinder as shown in FIG. 1 h . The munitions type (not shown) is placed around the cylinder and filled to a predetermined level see FIG. 1 i . FIG. 1 j , shows the CMDP circuitry (CMD) housing. The nose cone is secured onto the projectile see FIG. 1 k.
CMDP Circuitry Schematic (CMD)
[0047] For the purpose of the present description and appended claims, by way of schematic circuitry design (tested); the present invention describes the CMD electronic schematic and refers to components, operations and functions in FIG. 3 . The schematic diagram also shows an array of circuit components interfaced to create block circuit operations needed to make the CMD work.
[0048] The CMD is supplied voltage via switch s 4 , shown (lower left). The activation of s 4 simultaneously resets all onboard circuits via IC 4 A and IC 4 C (left center). The CMD is not limited to a manual power switch to power on, reset or power off the CMDP, it can also be equipped with an automatic power switching circuit that will accomplish the same function using an input code. Using an input code to control power to the CMD has many advantages.
[0049] A sync pulse initiates and prepares the data link input circuit for incoming data. Afterwards, data words are stored into memory via the data link input and IC 8 B (center). Data initially enters into memory via IC 8 B, which is immediately disabled after the data is received and tansferred. IC 14 B, IC 6 B, IC 8 D, and CTX (center down) together create a block circuit for data synchronization for incoming data to be stored into memory chips IC 2 , IC 3 and IC 7 B (center right). A security code, IC 7 A pin 11 simultaneously transfers memory to buss B, enables IC 10 B (left center) and disables IC 8 B. IC 10 B enables IC 8 C (upper left) and IC 12 (lower right). The CMD is now ready for the CMDP to be fired from the gun.
[0050] After the shell is fired, the combustion impacts the pressure switch enabling IC 10 A (upper left) to change states. IC 10 A (upper left) and the comparator circuit IC 11 , 5 & 12 (right) are enabled by the launch. ICIOA enables IC 6 A, U 1 and IC 13 B (upper center). IC 6 A controls the safety distance required for the projectile to travel before arming (enabling) one of two safety states for IC 8 A and IC 16 (upper center). U 1 initiates a continuous output pulse signal into IC 15 A to control IC 1 . IC 15 A is controlled by IC 8 A to increment and transfer data to buss A through IC 1 and IC 9 . IC 11 , IC 5 and IC 12 compare buses A and B. As the circuit computes the distance, the CMDP travels to the target area. If buss A equals buss B, IC 11 enables IC 13 A, then IC 13 A latches and arms the second IC 16 A safety detonating states. The detonation circuit changes states and detonates the munitions.
[0051] Many safety latch states are built into the circuitry to prevent faulty detonation. All aspects of the CMD circuitry activates only if pre-conditions are met.
[0000] Munitions Timer input & Output Timing Chart
[0052] FIGS. 10 a & 10 b refers to the waveforms for the input clock and CMD timing and state changes at: IC 7 A- 11 , IC 8 B- 6 , IC 8 C- 9 , IC 8 C- 8 , IC 6 A- 2 , IC 6 A- 4 , IC 13 - 16 , IC 13 - 12 , IC 8 A- 2 and IC 8 A- 3 . Clock 1 , refers to the input clock frequency of the input device, and Clock 2 , refers to the clock frequency of the CMD. The frequencies for both units are the same and use SYNCH to synchronized them for data input transfer. Also, all timing signals depend on the clock operating frequency for operation.
CMDP Operation, Functionality and Purpose
[0053] For the purpose of the present description and appended claims, by way of operation, functionality and purpose; a CMDP fired from a gun will travel a predetermined distance and upon arriving at the designated distance will detonate. The present invention relates to the firing of a shell (projectile), from a gun, gun of a tank or modified grenade launcher, which detonates accurately along a fight path at, above or beside a target from a predetermined distance. A gun equipped with a laser range finder acquires the distance to the target and downloads the data into the projectile's electronic memory with only a touch of a button while the (projectile) shell is still inside the gun. Alternately, a gun equipped with a range dialer selects a distance to a target area and downloads the data into the projectile's electronic memory with a touch of the trigger while the projectile/shell is still inside the gun. Instantaneously, as the propellant inside the shell ignites and burns; it launches the projectile. The combustible force inside the shell impacts the pressure switch FIG. 1 e , activating and initiating the counter circuitry onboard the CMDP. As the projectile exits the gun and travels downrange towards the target, it clears a predetermined safe distance before enabling one of two munitions detonation safety states. This feature assures friendly forces are well outside the impact zone before target detonation. Also, simultaneously to the projectile's launch, the counter circuit initiates counting while still inside the gun and continues counting and comparing memory data until it reaches the target and detonates. After the memory and counter data compares and matches; a second safety detonator state enables and detonates the munitions.
[0054] The projectile's flight is totally dependant on direction and height, initial velocity and the aiming mechanism of the gun. The CMDP used in a modified grenade launcher can simultaneously download data into memory and trigger the gun. Although the laser range finder may be the optimum choice to select a distant target, a range dial selection mode can be used in conjunction to rapidly engage the same distant target or newly acquired distant targets. Additional range can be added or subtracted from the range finder data to assure exact target detonation anywhere along the CMDP's flight path. The CMDP is a fire and forget device; is not dependant on target impact and will detonate upon reaching its predetermined range. After the first projectile is fired, the user can engage another target using the same range data or newly acquired data. The CMDP is self-contained and requires no additional signaling source after launching to acquire the target. The CMDP can be fitted with many types of munitions; white phosphorus, illumination, high explosive, smoke, fragmentation and cluster munitions or any number of munitions in the military's inventory. This new technology will dominate battles, minimize friendly causalities and reduce the duration of wars.
[0055] Although the invention has been shown and described with respect to a certain preferred embodiment, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon reading and understanding of this specification. The present invention includes all such equivalent alterations and modifications and is limited only by the scope of the claims above. | A projectile, (Cruise Munition Detonator Projectile or CMDP), can be fired from a tank, modified grenade launcher or gun using a laser range finder, radar or manual input (dialer or keypad) range selector. The CMDP will prevent, neutralize and eliminate enemy close infighting. The CMDP can defend aircraft against SAM, shoulder launched missiles, and air-to-air missiles. The CMDP will travel a predetermined programmed distance and detonate in front of or behind, over or beside, or in the mist of a target. The CMDP allows small forces to strategically neutralize larger forces with devastating effect. The CMDP is a force multiplier and an anti-personnel weapon. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to a start control system for an alcohol engine capable of readily starting the engine by enhancing vaporization of a fuel to be supplied to the engine.
Because of possible shortage of fuel and the demand for purifying exhaust gas, the system using both gasoline and alcohol as the fuel has been practically used. A vehicle using this system (hereinafter called a Flexible Fuel Vehicle (FFV)) runs by using not only gasoline but also a mixed fuel of gasoline and alcohol, or only alcohol. The alcohol concentration (content) of a fuel used by FFV changes from 0% (only gasoline) to 100% (only alcohol) depending upon the circumstances of fuel supply.
An alcohol fuel has characteristics of a hard vaporization at a low temperature as compared with a gasoline fuel, a large latent heat of vaporization, a high flashing temperature, and the like. The engine output performance changes considerably with the alcohol concentration depending upon engine temperature at that time. Especially, there is a problem that the low temperature start performance is degraded at a high alcohol concentration.
There is known a technique dealing with the above problems, wherein the start performance can be improved by enhancing the vaporization of a fuel by using heating means such as a heater. For instance, there is disclosed in Japanese Patent Laid-open Publication No. 57-52665 the technique according to which a heater for heating an air intake pipe is controlled in accordance with an output from an alcohol concentration sensor in such a way that the calorific power of the heater is increased when the alcohol concentration becomes equal to or larger than a preset value.
The calorific power of the heater required for starting an engine changes largely with the engine temperature. Accordingly, if the calorific power of the heater is determined merely by the alcohol concentration, there is a possibility of failing to start an engine at a low temperature.
Further, if the calorific power is made large at a low engine temperature, electric power may be consumed wastefully when the atmospheric temperature rises or when the alcohol concentration lowers.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a start control system for an alcohol engine capable of setting a proper necessary calorific power of heating means in accordance with alcohol concentration and engine temperature, and improving the start performance of the engine without wasting electric power.
It is another object of the present invention to provide a start control system for an alcohol engine capable of setting a proper necessary calorific power of the heating means in accordance with the alcohol concentration and the engine temperature, performing an optimum control while considering the consumption of the necessary calorific power, and improving the start performance of the engine without increasing the battery capacity.
In order to achieve the abovementioned objects, there is provided a start control system for an alcohol engine having heater means for heating fuel injected by an injector, comprising: sensing means for sensing an alcohol concentration of the fuel; detecting means for detecting an engine temperature; judging means responsive to said alcohol concentration and said engine temperature for judging an engine start disable state; computing means responsive to said alcohol concentration and said engine temperature for computing a necessary calorific power of the heater sufficient for enhancement of vaporization of the fuel in said engine start disabled state; and controlling means responsive to said necessary calorific power for controlling a time for turning on the heater.
Specifically, the start judging means judges if the engine can be started or not, in accordance with the alcohol concentration of the fuel and the engine temperature. If it is judged that the engine cannot be started, the necessary calorific power calculating means calculates the necessary calorific power of the heating means sufficient for the enhancement of vaporization of the fuel and allowing the engine to start, in accordance with said alcohol concentration and said engine temperature.
The controlling means compares said necessary calorific power with a predetermined reference value, and if said necessary calorific power is larger than said reference value, a time to turn on said heating means is set in accordance with said necessary calorific power, and during this time heating means is powered.
In order to achieve the above-described second object of this invention, the controlling means compares said necessary calorific power calculated by said necessary calorific power is larger than said reference value, said heating means is powered for a predetermined time period and thereafter a starter motor is driven.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 to 5 show the first embodiment according to the first aspect of this invention, wherein:
FIGS. 1, 1A and 1B are functional block diagrams of a control unit;
FIG. 2 is a schematic diagram of an engine control system;
FIG. 3 illustrates a starting enable state judging map;
FIG. 4 illustrates a starting fuel injection amount map; and
FIGS. 5A, 5B and 5C are flow charts showing the start control procedure;
FIGS. 6 to 8 shows the second embodiment according to the first aspect of this invention, wherein:
FIGS. 6, 6A and 6B are functional block diagrams of a control unit;
FIG. 7 is a schematic diagram of an engine control system; and
FIGS. 8A, 8B and 8C are flow charts showing the start control procedure; and
FIGS. 9, 9A and 9B are functional block diagrams of a control unit of the first embodiment according to the second aspect of this invention; and
FIGS. 10, 10A and 10B are functional block diagrams of a control unit of the second embodiment according to the second aspect of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Structure of Engine Control System
Referring to FIG. 2, reference numeral 1 generally represents an FFV alcohol engine of a horizontally opposing four cylinder type. An intake manifold 3 communicates with an air intake port 2a formed in a cylinder head 2 of the engine 1. A throttle chamber 5 communicates with the intake manifold 3 via an air chamber 4. An air cleaner 7 is mounted at an air intake pipe 6 at the upstream of the throttle chamber 5.
An intake air flow sensor (in FIG. 2 a hot wire type air flow meter) 8 is mounted at the downstream near the air cleaner 7 in the air intake pipe 6. An injector 10 is mounted at the downstream of the throttle valve 5a in the throttle chamber 5. This injector 10 is in communication with a fuel tank 12 via a fuel supply passage 11.
In this fuel tank 12, there is stored a fuel whose alcohol concentration A (%) differs depending upon the circumstance when user supplies the fuel. The fuel may be only alcohol, a mixed fuel of gasoline and alcohol, or only gasoline.
There are mounted at the fuel supply passage 11 a fuel pump 13 and an alcohol concentration sensor 14 in this order as viewed from the fuel tank 12. The injector 10 communicates with a fuel chamber 18a of a pressure regulator 18 via a return passage 16.
The fuel chamber 18a of the pressure regulator 18 communicates at its downstream with the fuel tank 12, and a pressure regulating chamber 18b communicates at the downstream near the throttle valve 5a. The pressure regulator 18 makes constant the pressure difference between the fuel pressure in the fuel supply passage 11 and the pressure at the downstream near the throttle valve 5a so that the fuel injection amount from the injector 10 is controlled so as not to change.
An ignition plug 17 is mounted at each cylinder of the cylinder head 2, the ignition plug 17 extending its tip within a combustion chamber. A crank rotor 21 is coupled to a crank shaft 1b of the engine 1. A crank angle sensor 22 is mounted opposing the outer periphery of the crank rotor 21, the sensor being constructed of an electromagnetic pickup for detecting the crank angle.
Under the air chamber 4 of the intake manifold 3, there is mounted heating means including first and second heaters 23 and 24. A coolant temperature sensor 25 is mounted facing a coolant passage (not shown) serving as a riser formed in the intake manifold 3.
At an exhaust pipe 26 communicating with an exhaust port 2b of the cylinder head 2, there is mounted an O 2 sensor 27. Reference numeral 28 represents a catalytic converter.
Arrangement of Control Unit
Reference numeral 31 generally represents a control unit. In this control unit 31, interconnected together via a bus line 36 are a CPU (Central Processing Unit) 32, a ROM 33, a RAM 34 and an I/O interface 35. The control unit 31 is supplied with a predetermined stable and constant voltage from a constant voltage circuit 37.
The constant voltage circuit 37 is connected to a relay contact 40a of an ignition relay 40 which is connected to a battery 39 via an ignition switch 38, so that the constant voltage circuit 37 supplies a control power to the control unit 31 when the ignition switch 38 connected in series to the battery 39 is turned on and supplies a backup power when the ignition switch 38 is turned off.
The battery 39 is connected to a starter switch 41, a relay contact 42a of a first heater relay 42, and a relay contact 43a of a second heater relay 43. The starter switch 41 is connected to a starter motor 45 via a relay contact 44a of a starter motor relay 44.
The above-described sensors 8, 14, 22, 25, 27, the relay contact 40a of the ignition relay 40, switches such as the starter switch 41, and the like are connected to input ports of the I/O interface 35.
To output ports of the I/O interface 35, there are connected the ignition plug 17 via an igniter 29, the injector 10 and the fuel pump 13 via the driver circuit 46, the first and second heater relays 42 and 43, the starter motor relay 44, and a LED 47 serving as display means of the heater operation.
The ROM 33 stores therein fixed data such as control programs, a start judging map MPST and a start fuel injection amount map MPFST. The RAM 34 stores therein processed output signals from various sensors and switches, and data processed by the CPU 32.
In accordance with the control programs stored in the ROM 33, the CPU 32 performs an engine start control by using engine state parameters detected by various sensors and switches and the alcohol concentration of a fuel detected by the alcohol concentration sensor 14. In this engine start control, the control unit 31 controls the electric power supplied to the first and second heaters 23 and 24 to thereby enhance the vaporization of the fuel injected from the injector 10 and readily start the engine.
After the engine starts, the control changes to the normal control whereby calculated are the fuel injection amount, ignition timing and the like, and outputted are a driving pulse width signal for the injector and an ignition signal for the ignition plug 17.
Function and Structure of Control Apparatus
As shown in FIG. 1, the start control function of the control unit 31 is constructed of starter switch state judging means 51, alcohol concentration calculating means 52, start judging means 53, start judging map MPST, vaporization latent heat calculating means 54, fuel flow rate calculating means 55, start fuel injection amount map MPFST, necessary calorific power calculating means 56, and start controlling means 57.
The start controlling means 57 is constructed of comparing means 57a, operation time setting means 57b, timer means 57c, starter motor driving means 57d, first heater driving means 57e, and second heater driving means 57f.
The starter switch state judging means 51 judges if the starter switch 41 is turned on or off. If the starter switch 41 is turned on, a trigger signal is outputted to the start judging means 53. If the starter switch 41 is turned off, the start controlling means 57 makes the starter motor relay 44 turn off, and the first heater driving means 57e makes the first heater relay 42 turn off and hence the first relay 23 turn off.
The alcohol concentration calculating means 52 reads a signal outputted from the alcohol concentration sensor 14 and calculates the alcohol concentration A of the fuel supplied to the injector 10.
Upon receiving of the trigger signal from the starter switch state judging means 51, the start judging means 53 judges if the engine can be started in accordance with the start judging map MPST by using as a parameter the alcohol concentration A calculated by the alcohol concentration calculating means 52 and the engine temperature derived from the coolant temperature Tw detected by the coolant temperature sensor 25.
If it is judged that the engine 1 can be started, the starter motor driving means 57d makes the starter motor relay 44 turn on and hence the starter motor 45 turn on. If it is judged that the engine cannot be started, a calculation start signal is output to the vaporization latent heat calculating means 54 and the fuel flow rate calculating means 55.
As shown in FIG. 3, in the start judging map MPST, the region of the alcohol concentration A at which the fuel injected by the injector can be used for starting the engine without heating it, and the region of the alcohol concentration A at which the fuel cannot be used for starting the engine, are specified beforehand through experiment or the like, with respect to the engine temperature typically represented by the coolant temperature Tw, and stored in the ROM 33 at predetermined addresses.
Instead of using the coolant temperature Tw from the coolant temperature sensor 25, oil temperature, fuel temperature or the like may be used.
Upon receiving of the calculation start signal from the start judging means 53, the vaporization latent heat calculating means 54 calculates the vaporization latent heat (carburetion heat) QS in accordance with the alcohol concentration A. This vaporization latent heat QSA is determined in accordance with the alcohol concentration A so that it can be determined by using a function f(A) of the alcohol concentration A (QS=f(A)).
Receiving the calculation start signal from the start judging means 53, the fuel flow rate calculating means 54 searches start fuel injection amount Ti from the start fuel injection amount map MPST by using as a parameter the coolant temperature Tw and the alcohol concentration A. In accordance with this searched start fuel injection amount Ti, fuel flow rate FL per unit time of the fuel injected from the injector 10 is calculated.
As shown in FIG. 4, the start fuel injection amount map MPFST stores a plurality of fixed fuel injection amounts to be injected from the injector at the engine start using as a parameter the alcohol concentration A and the coolant temperature Tw at predetermined addresses in the ROM 33. It is necessary to use a lower air/fuel ratio as the alcohol concentration A becomes higher so that a larger start fuel injection amount Ti is stored. On the other hand, it is necessary to increase the amount as the coolant temperature Tw lowers so that a larger start fuel injection amount Ti is stored.
In accordance with the fuel flow rate FL and the vaporization latent heat QS, the necessary calorific power calculating means 56 calculates calorific power necessary for the heating means including the first and second heaters 23 and 24 for the start of the engine (W =QS×FL).
The comparing means 57a compares the reference value WS with the necessary calorific power W calculated by the necessary calorific power calculating means 57. If w≦WS, the starter motor driving means 57d makes the starter motor relay 44 turn on, and the first heater driving means 57e makes the first heater relay 42 and the LED 47 turn on, to thereby turn on the starter motor 45 and the first heater 23 and present a heater operation display on the LED 47. If W>WS, a trigger signal is output from the operation time setting means 57b.
Upon receiving the trigger signal from the comparing means 57a, the operation time setting means 57b sets operation time for the timer means 57c, i.e., conduction time t while the first and second heaters 23 and 24 are turned on, by means of calculation or map searching in accordance with the necessary calorific power W.
The operation time is set longer as the necessary calorific power W becomes larger, and shorter as the necessary calorific power W becomes smaller. Namely, the necessary calorific power W (cal) is given by the Joule's law as: ##EQU1## where R is a heater resistance, I is a current, t is a conduction time, and V is a voltage applied to the heater. Taking an efficiency as μ,the equation (1) becomes:
W=0.24×μ×V.sup.2 ×t/R
The heater conduction time t can therefore be calculated by
t=W×R/(0.24×μ×V.sup.2) ... (2)
Accordingly, assuming that the heater resistance R, heater voltage V and efficiency μ are constant, the heater conduction time (i.e., operation time) t can be calculated from a function f(W) of the necessary calorific power W, or can be searched from an optimum operation time map obtained through experiments, by using as a parameter the necessary calorific power W.
With the timer means 57c, during the operation time t set by the operation time setting means 57b, the first heater driving means 57e and the second heater driving means 57f make the first and second heater relays 42 and 43 turn on to power on the first and second heaters 23 and 24 and the LED 47 serving as heater operation display means. During this period, the starter motor relay 44 is maintained off so that the starter motor 45 is not driven.
Namely, through the comparison with the reference value WS, it is judged if the necessary calorific power W can be supplied sufficiently from the first heater 23 only or if the necessary calorific power W should be supplied from both the first and second heaters 23 and 24. If the necessary calorific power W is equal to or smaller than the reference value WS, only the first heater 23 is turned on. In this small power consumption case, the first heater 23 is turned on and the starter motor 45 is turned on to start the engine.
Alternatively, if the necessary calorific power W is larger than the reference value WS, both the first and second heaters 23 and 24 are turned on to supply the necessary calorific power W. In this large power consumption case, the operation time setting means 57b sets the optimum conduction time t for the first and second heater relays 42 and 43 so that the first and second heaters 23 and 24 are maintained turned on during this conduction time t to reduce the burden on the battery 39.
Operation
Next, the time sequential operation of the embodiment constructed as above will be described with reference to the flow chart shown in FIG. 5.
The program shown in the flow chart of FIG. 5 is an initial control program which starts running upon turning on the start switch 41. First, at a step S101, the initialization is carried out such as for counters and for the establishment of the initial conditions of relays 42, 43 and 44.
Specifically, the relays 42, 43, and 44 are made turned off. At a next step S102, the coolant temperature Tw is read from the coolant temperature sensor 25, and the alcohol concentration A is calculated from a signal output from the alcohol concentration sensor 14.
At a next step S103, by using as a parameter the coolant temperature Tw and calculated alcohol concentration A respectively obtained at the step S102, it is judged by using the start judging map MPST if the engine can be started.
If it is judged at the step S103 that the engine can be started, then the control advances to a step S104 whereat the starter motor driving means 57d makes the starter motor relay 44 turn on and hence the starter motor 45 turn on. At a step S105, it is checked if the starter switch 41 is made turned off.
If the starter switch 41 is not made turned off, the control returns from the step S105 to the step S104 to thereby continue to turn on the starter motor relay 44. If the starter switch 41 is made turned off, the control advances from the step S105 to a step S106 whereat the starter relay 44 is made turned on and the starter motor 45 is turned off to terminate the program.
If it is judged at the step S103 that the engine cannot be started, the control advances from the step S103 to a step S107 whereat the vaporization latent heat QS is calculated in accordance with the alcohol concentration A calculated at the step S102 (QS=f(A))), and thereafter the control advances to a step S108.
At the step S108, by using as a parameter the coolant temperature Tw and the alcohol concentration A, the start fuel injection amount Ti is searched from the start fuel injection amount map MPFST. The fuel flow rate FL per unit time is calculated from the start fuel injection amount Ti.
Next, at a step S109 the necessary heater calorific power W is calculated from the vaporization latent heat QS calculated at the step S107 and the fuel flow rate FL calculated at the step S108 (W=QS×FL).
At a step S110 the reference value WS is compared with the necessary heater calorific power W calculated at the step S109 to thereby judge if only the first heater 23 is to be powered or both the first and second heaters 23 and 24 are to be powered.
If WS≧W, the control advances from the step S110 to a step S111 whereat the starter motor relay 44 is turned on to drive the starter motor 45, and the first heater relay 42 is turned on to heat the fuel injected from the injector 10. At the same time, the LED 47 is powered to indicate that the heater is now powered.
Next, at a step S112 it is judged if the starter switch 41 is made turned off. If not, the control returns to the step S111 to maintain to turn on the starter motor relay 44, the first heater relay 42 and the LED 47. If the starter switch is made turned off, the control advances from the step S112 to a step S113.
At step S113, the starter motor relay 44, the first heater relay 42 and the starter motor 45 are turned off, and also the LED 47 is turned off to stop the heater operation display to thereafter terminate the program.
If it is judged at the step S110 as WS<W, the control advances from the step S110 to a step S114. At the step S114, the operation time Cn for a counter of the timer means 57c is determined and set to the counter in accordance with the necessary calorific power W calculated at the step S109.
Next, the counter starts counting. At a step S115, the count value C of the counter is incremented by 1. At a step S116, the first and second heater relays 42 and 43 are turned on and the LED 47 is powered to give a heater operation display.
Next, at a step S117, it is judged if the count C reaches the operation time Cn. If C<Cn, the control returns to the step S115 to continue counting. If C≧Cn, i.e., if the count C reaches the operation time Cn, the control advances to a step S118.
At the step S118, the count C of the counter is clarified. The control advances from the step S118 to a step S119. At the step S119, the first and second heater relays 42 and 43 are turned off, and also the LED 47 is turned off to stop the heater operation display.
It is judged at a step S120 if the starter switch 41 is made turned off. If not, at a step S121 the starter motor relay 4 is turned on to drive the starter motor 45 until the starter switch 41 is judged at the step S120 to be made turned off.
If it is judged at the step S120 that the starter switch 41 is turned off, the starter motor relay 44 is turned off at a step S122 to terminate the program.
2nd Embodiment
FIGS. 6 to 8 shows the second embodiment according to the first aspect of this invention.
The same elements and means as shown in the first embodiment are represented by the same reference numerals, so that the description therefor is omitted.
Structure of Engine Control System and Control Unit
As shown in FIG. 7, heating means including a heater 20 is mounted under the air chamber 4 of the intake manifold 3. This heater 20 is connected to the battery 39 via a relay contact 48a of a heater relay 48 and via a regulator 50 comprising a heater calorific power regulating relay 49 and a resistor R.
The heater relay 48 and the heater calorific power regulating relay 49 are connected to the driving circuit 46 of the control unit 31. A relay contact 48a of the heater relay 48 is connected to the battery 39, and an interconnection of a parallel circuit of the resistor R and the heater calorific power regulating relay 49 is connected to the relay contact 48a of the heater relay 48.
Function and Structure of Control Unit
As shown in FIG. 6, the engine start function of the control unit 31 is constructed of starter switch state judging means 61, alcohol concentration calculating means 52, start judging means 53, a start judging map MPST, vaporization latent heat calculating means 54, a fuel flow rate calculating means 55, a start fuel injection amount map MPFST, necessary calorific power calculating means 56, and start controlling means 62. The start controlling means 62 is constructed of comparing means 62a, operating time setting means 57b, timer means 62b, starter motor driving means 57d, heater driving means 62c and regulator driving means 62d.
When the starter switch 41 is turned on, the starter switch state judging means 61 outputs a trigger signal to the start judging means 53. When the starter switch 41 is turned off, the starter motor driving means 57d makes the starter motor relay 44 turn off and hence the starter motor 45 turn off, and the heater driving means 62c makes the heater relay 48 turn off not to power the heater 20.
The comparing means 57a compares necessary calorific power W calculated by the necessary calorific power calculating means 56 with a reference value WS. If WS≧W, the starter motor driving means 57d makes the starter motor relay 44 turn on to drive the starter motor 45, and the heater driving means 62c makes the heater relay 48 turn on.
In this case, the heater calorific power regulating relay 49 is maintained off so that the heater 20 is powered at a low power level via the route from the relay contact 48a of the heater relay 48 and the resistor R of the heater calorific power regulating means 50. At the same time, a LED 47 is powered to present a heater operation display. If WS<W, a trigger signal is outputted to the operation time setting means 57b.
With timer means 62b, during the operation time t set by the operation time setting means 57b, the heater driving means 62c makes the heater relay 48 turn on, and the regulator driving means 62d makes the heater calorific regulating relay 49 turn on. Accordingly, the heater 20 is directly connected to the battery 39 to make large the calorific power.
Since the power consumption by the heater 20 is large during the operation time, the starter motor relay 44 is turned off not to drive the starter motor 45. After the lapse of the operation time t, the heater relay 48 and the heater calorific power regulating relay 49 are turned off not to power the heater 20. The starter motor driving means 57d makes the starter motor relay 44 turn on to drive the starter motor 45.
Operation
Next, the operation of the second embodiment will be described with reference to the flow chart of FIG. 8, only with respect to steps that differ from the operation of the first embodiment.
After executing the procedure from the step S101 to the S110 in the similar manner as the first embodiment, the necessary calorific power W is compared with the reference value WS at the step S110. If WS≧W, the control advances from the step S110 to a step S201. At the step S201, the starter motor relay 44 and the heater relay 48 are turned on to drive the starter motor 45 and power the heater 20 at a low power level. At the same time, the LED 47 is powered to display that the heater is now powered.
Next, at the step S112 it is judged if the starter switch 41 is made turned off. If not, the control returns to the step S201 to continue to turn on the starter motor relay 44, the heater relay 48 and the LED 47. If the starter switch 41 is made turned off, the control advances from the step S112 to a step S202.
At the step S202, the starter motor relay 44 and the heater relay 48 are turned off, the starter motor 45 and the heater 20 are turned off, and the LED 47 is turned off to stop the heater operation display and terminate the program.
If WS<W at the step S110, the control advances from the step S110 to the step S114. At the step S114, the operation time Cn is determined and set to a counter of the timer means 62b in accordance with the necessary calorific power W calculated at the step S109.
Next, the counter starts counting At the step S115, the count value C of the counter is incremented by 1. At a step S203, the heater relay 48 and the heater calorific power regulating relay 49 are turned on to power the heater 20 at a high power level. In addition, the LED 47 is powered to indicate that the heater is now turned on.
Next, at the step S117, it is judged if the count C reaches the operation time Cn. If C<Cn, the control returns to the step S115 to continue counting. If C≧Cn, i.e., if the count reaches the operation time Cn, the control advances to the step S118.
At the step S118, the count C is cleared (C=0) to advance to a step S204. At the step S204, the heater relay 48 and the heater calorific power regulating relay 49 are turned off, and the LED 47 is turned off to stop the heater operation display. At the step S120, the starter motor 45 is driven in the similar manner as the procedure of the first embodiment and the program is terminated.
The present invention is not limited to the above embodiment. Three or more heaters may be used to control the engine start finely. Furthermore, a heater may be mounted at the upstream near each air intake port 2a of each cylinder at the intake manifold 3 so that an engine of a multi point injection type may also use the system of the present invention. An engine of an electronically controlled carburetor type may also be applied.
As described so far, according to the first aspect of this invention, when start judging means judges that the engine can be started, necessary calorific power calculating means calculates a necessary calorific power of heating means sufficient for enhancing the vaporization of a fuel and enabling the engine start, in accordance with the engine temperature and the alcohol concentration, and if the necessary calorific power is larger than the predetermined reference value, start control means sets the conduction time of the heating means in accordance with the necessary calorific power. Accordingly, if the necessary calorific power of the heating means is large so that much power will be consumed, the conduction time of the heating means can be limited to a minimum to thus reduce the load of the battery, and prevent wasteful energy consumption.
FIGS. 9 and 10 show two embodiments according to the second aspect of this invention, corresponding to the two embodiments (FIGS. 1 and 6) according to the first aspect of this invention.
In the first embodiment shown in FIG. 9, the start control means 57 is constructed of comparing means 57a, timer means 57c, starter motor driving means 57d, first heater driving means 57e, and second heater driving means 57f.
In the first embodiment shown in FIG. 9, the comparing means 57a compares necessary calorific power W calculated by the necessary calorific power calculating means 56 with the reference value WS. If W≦WS, the starter motor driving means 57d makes a starter motor relay 44 turn on, and the first heater driving means 57e makes a first heater relay 42 and a LED 47 turn on to thereby drive a starter motor 45 and a first heater 23 and power the LED 47 to present a heater operation display. If W>WS, the timer means 57c outputs a trigger signal.
Upon receiving the trigger signal from the comparing means 57a, the timer means 57c causes then the first heater driving means 57e and the second heater driving means 57f to make the first and second heater relays 42 and 43 turn on for a predetermined time period (e.g., 3 seconds) so that the first and second heaters 23 and 24 and the LED 47 are turned on. During this time period, the starter motor relay 44 is made turned off not to drive the starter motor 45.
Specifically, through the comparison with the reference value WS, it is judged if the necessary calorific power W can be supplied sufficiently from the first heater 23 only or if the necessary calorific power W should be supplied from both the first and second heaters 23 and 24. If the necessary calorific power W is equal to or smaller than the reference value WS, only the first heater 23 is turned on. In this small power consumption case, the first heater 23 is turned on and the starter motor 45 is turned on to start the engine.
Alternatively, if the necessary calorific power W is larger than the reference value WS, both the first and second heaters 23 and 24 are turned on to supply the necessary calorific power W. In this large power consumption case, the timer means 57c makes the first and second heater relays 42 and 43 turn on for the predetermined time period, and during this period the starter motor 45 is turned off.
FIG. 10 shows the second embodiment according to the second aspect of this invention. This embodiment corresponds to the second embodiment (shown in FIG. 6) according to the first aspect of this invention.
As described so far, according to the second aspect of this invention, when start judging means judges that the engine can be started, necessary calorific power calculating means calculates a necessary calorific power of heating means sufficient for enhancing the vaporization of a fuel and enabling the engine start, in accordance with the engine temperature and the alcohol concentration. Accordingly, the heating means will not consume power wastefully and will prevent energy loss.
Furthermore, start control means compares the necessary calorific power with a predetermined reference value. If the necessary calorific power is larger than the reference value, the heating means is driven for a predetermined period, and thereafter the starter motor is driven. Accordingly, even if the heating means consumes much energy for the necessary calorific power, the engine can be started smoothly without increasing the battery capacity.
Although the present invention has been fully described by way of the preferred embodiments thereof with reference to the accompanying drawings, various exchanges and modifications will be apparent to those of working skill in this technical field. Therefore, unless otherwise these changes and modifications depart from the scope of the present invention, they should be construed as being included therein. | A start control system for an alcohol engine having heater means for heating fuel injected by an injector, comprising: sensing means for sensing an alcohol concentration of the fuel; detecting means for detecting an engine temperature; judging means responsive to said alcohol concentration and said engine temperature for judging an engine start disable state; computing means responsive to said alcohol concentration and said engine temperature for computing a necessary calorific power of the heater sufficient for enhancement of vaporization of the fuel in said engine start disabled state; and controlling means responsive to said necessary calorific power for controlling a time for turning on the heater. | 5 |
INCORPORATION BY REFERENCE
The disclosure of Japanese Patent Application No. 2006-280330 filed on Oct. 13, 2006 including the specification, drawings and abstract is incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a vehicle steering control device and a vehicle steering control method and, more particularly, to a vehicle steering control device and vehicle steering control method that change control rules at the time of automatic steering.
2. Description of the Related Art
As a related-art vehicle steering control device, Japanese Patent Application Publication No. 2005-324744 (JP-A-2005-324744), for example, discloses a vehicular automatic steering device capable of selecting and disengaging an automatic steering control. In this disclosed technology, when the automatic steering control is selected, a front wheel steering control device starts the automatic steering control after a rear wheel steering control has stopped at a neutral position. When the selection of the automatic steering control is cancelled, the rear wheel steering control device starts the rear wheel steering control after the automatic steering control has stopped. Thus, this technology substantially avoids the discomfort caused to the driver and the like and prevents the wobbling of the vehicle at the time of the automatic steering control.
However, even with the technology in which the start timing of the automatic steering control is prescribed as described above, it sometimes happens that at the time of the automatic steering, the vehicle is not stable and the driver feels discomfort, in comparison with the time of the manual steering performed by the driver.
SUMMARY OF THE INVENTION
The invention provides a vehicle steering control device that can further stabilize the vehicle and make the driver feel secured and comfortable at the time of automatic steering.
A first aspect of the invention provides a vehicle steering control device capable of executing automatic steering and manual steering characterized by including: an automatic control amount-setting device that sets a target automatic control amount based on information about behavior of a vehicle and about ambient environment; a steering control amount-setting device that sets a target steering amount based on a manual steering amount input by a driver and the target automatic control amount set by the automatic steering amount-setting device; and a steering device that steers based on the target steering amount set by the steering control amount-setting device, wherein when a contribution of the target automatic control amount is larger in setting of the target steering amount than the contribution of the manual steering amount, the steering control amount-setting device sets the target steering amount so as to better a responsiveness in a lateral shift of the vehicle relatively to the responsiveness in turning of the vehicle, in comparison with when the contribution of the target automatic control amount is equal to or smaller in the setting of the target steering amount than the contribution of the manual steering amount.
According to this construction, when the contribution of the target automatic control amount is larger in the setting of the target steering amount than the contribution of the manual steering amount, the steering control amount-setting device sets the target steering amount so as to better the responsiveness in the lateral shift of the vehicle relatively to the responsiveness in the turning of the vehicle, in comparison with when the contribution of the target automatic control amount is equal to or smaller in the setting of the target steering amount than the contribution of the manual steering amount. When the construction of the target automatic control amount is larger in the setting of the target steering amount than the contribution of the manual steering amount, that is, when the vehicle is running under the automatic control, it is generally often the case that the responsiveness in the lateral shift is required more than the responsiveness in the turning at the time of the execution of a constant-speed run control or the like. Therefore, since during the automatic control, the steering control amount-setting device sets the target steering amount so as to better the responsiveness in the lateral shift relatively to the responsiveness of the turning, the stabilization of the vehicle can be further improved and the driver can be caused to feel secured and comfortable during the automatic steering.
The automatic control amount-setting device may set the target automatic control amount so that a predetermined vehicle speed is maintained, and therefore can be applied to the time of the CC control (cruise control).
Furthermore, the automatic control amount-setting device may set the target automatic control amount so that an inter-vehicle distance to a preceding vehicle is kept at a predetermined value, and therefore can be applied to the time of the ACC control (adaptive cruise control).
Furthermore, the automatic control amount-setting device may set the target automatic control amount so that the vehicle stays and runs in a predetermined lane, and therefore can be applied to the time of the LKA (lane keeping assist) control.
Furthermore, when the contribution of the target automatic control amount is larger in the setting of the target steering amount than the contribution of the manual steering amount, the steering control amount-setting device may set the target steering amount so that a phase delay of a lateral acceleration of the vehicle relative to the steering amount becomes small, in comparison with when the contribution of the target automatic control amount is equal to or smaller in the setting of the target steering amount than the contribution of the manual steering amount.
According to this construction, since during the automatic control, the steering control amount-setting device sets the target steering amount so that the phase delay of the lateral acceleration relative to the steering amount becomes small, it is possible to improve the responsiveness in the lateral shift during the automatic control.
Furthermore, the steering device may steer a front wheel and a rear wheel individually based on the target steering amount, and when the contribution of the target automatic control amount is larger in the setting of the target steering amount than the contribution of the manual steering amount, the steering control amount-setting device may set the target steering amount so that the steering amount of the rear wheel becomes large, in comparison with when the contribution of the target automatic control amount is equal to or smaller in the setting of the target steering amount than the contribution of the manual steering amount.
According to this construction, the steering device steers the front wheel and the rear wheel individually based on the target steering amount, and the steering control amount-setting device sets the target steering amount so that the steering amount of the rear wheel becomes large at the time of the automatic control. Therefore, the amount of the turning is restrained and, on the other hand, the responsiveness in the lateral shift further improves, so that the stabilization of the vehicle can be further improved and the driver can be caused to feel secured and comfortable.
A second aspect of the invention provides a vehicle steering control method capable of executing automatic steering and manual steering characterized by including: setting a target automatic control amount based on information about behavior of a vehicle and about ambient environment; setting a target steering amount based on a manual steering amount input by a driver and the set target automatic control amount; and steering based on the set target steering amount, wherein when a contribution of the target automatic control amount is larger in setting of the target steering amount than the contribution of the manual steering amount, the target steering amount is set so as to better a responsiveness in a lateral shift of the vehicle relatively to the responsiveness in turning of the vehicle, in comparison with when the contribution of the target automatic control amount is equal to or smaller in the setting of the target steering amount than the contribution of the manual steering amount.
According to the vehicle steering control device and method of the aspects of the invention, it is possible to further improve the stability of the vehicle at the time of the automatic steering and cause the driver to feel secured and comfortable.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and further objects, features and advantages of the invention will become apparent from the following description of preferred embodiments with reference to the accompanying drawings, wherein like numerals are used to represent like elements and wherein:
FIG. 1 is block diagram showing a construction of a vehicle steering control device in accordance with a first embodiment of the invention;
FIG. 2 is a block diagram showing a construction of an A4WS-ECU in accordance with the first embodiment;
FIG. 3 is a flowchart showing an operation of the vehicle steering control device in accordance with the first embodiment;
FIG. 4 is a block diagram showing a control rule of a computation portion at the time of the manual steering in accordance with the first embodiment;
FIG. 5 is a block diagram showing a control rule of the computation portion at the time of the automatic steering in accordance with the first embodiment;
FIG. 6 is a Bode diagram showing a frequency response of the lateral acceleration of the control rule in accordance with the first embodiment;
FIG. 7 is a diagram showing a control map of the yaw rate gain in accordance with a second embodiment;
FIG. 8 is a diagram showing a control map of the slip angle gain in accordance with the second embodiment;
FIG. 9 is a diagram showing a control map of the slip angle advancement time in accordance with the second embodiment;
FIG. 10 is a block diagram showing a control rule of a computation portion at the time of the automatic steering in accordance with the second embodiment;
FIG. 11 is a Bode diagram showing a frequency response of the lateral acceleration of the control rule in accordance with the second embodiment;
FIG. 12 is a block diagram showing a construction of an A4WS-ECU in accordance with a third embodiment; and
FIG. 13 is a flowchart showing an operation of the vehicle steering control device in accordance with the third embodiment.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Hereinafter, vehicle steering control devices in accordance with embodiments of the invention will be described with reference to the accompanying drawings.
FIG. 1 is a block diagram showing a construction of a vehicle steering control device in accordance with a first embodiment of the invention. A vehicle steering control device of this embodiment is constructed so that either one of the manual steering and the automatic steering can be executed during the four-wheel steering, and steering control can be performed so as not to cause uncomfortable feeling to a driver at the time of the automatic steering.
As shown in FIG. 1 , a vehicle steering control device 10 of this embodiment includes a steering handle 12 that a driver operates at the time of the manual steering, a VGRS (variable gear ratio steering) actuator 22 that changes the gear ratio of the front wheel steering, and a front steer actuator 24 that performs the steering of the front wheels. The vehicle steering control device 10 also includes a steering angle sensor 14 that detects the steering angle, and a vehicle speed sensor 16 that detects the vehicle speed. The information detected by these sensors is output to an A4WS (active four-wheel steering)-ECU 18 .
The vehicle steering control device 10 includes a CC-ECU 30 that performs the CC control (cruise control), an ACC-ECU 32 that performs the ACC control (adaptive cruise control), and an LKA-ECU 34 that performs the LKA control (lane keeping assist control). These ECUs set predetermined target automatic control amounts on the basis of the vehicle behaviors and ambient environments detected by sensors and the like, such as the steering angle sensor 14 , the vehicle speed sensor 16 , etc. The CC-ECU 30 , the ACC-ECU 32 and the LKA control LKA-ECU 34 function as an automatic control amount-setting device. The target automatic control amounts set by the CC-ECU 30 , the ACC-ECU 32 and the LKA control LKA-ECU 34 are output to the A4WS-ECU 18 .
The A4WS-ECU 18 is provided for setting target steering amounts on the basis of the manual steering amount input by the driver via the steering handle 12 as well as the target automatic control amounts set by the CC-ECU 30 , the ACC-ECU 32 and the LKA-ECU 34 . The A4WS-ECU 18 functions as a steering control amount-setting device. The A4WS-ECU 18 outputs the target steering amount set in this manner to a VGRS-ECU 20 . The VGRS-ECU 20 outputs a drive signal to the VGRS actuator 22 so as to drive the front steer actuator 24 . In this manner, the VGRS-ECU 20 performs the automatic steering of the front wheels. Besides, the A4WS-ECU 18 outputs the target steering amount set in the foregoing manner to a rear steer ECU 26 . The rear steer ECU 26 performs the automatic steering of the rear wheels by outputting a drive signal to a rear steer actuator 28 to drive the rear steer actuator 28 . Therefore, the front steer actuator 24 and the rear steer actuator 28 function as a steering device.
Next, operations of the vehicle steering control device of the embodiment will be described. Firstly, a steering control in the two-wheel steering will be described. The control rule in the two-wheel steering is expressed by the following expressions (1) to (3).
EXPRESSION
1
γ
(
s
)
δ
(
s
)
=
ω
n
2
s
2
+
2
·
ζ
·
ω
n
·
s
+
ω
n
2
·
G
γ
·
(
1
+
T
γ
·
s
)
·
δ
f
(
s
)
δ
(
s
)
(
1
)
β
(
s
)
δ
(
s
)
=
ω
n
2
s
2
+
2
·
ζ
·
ω
n
·
s
+
ω
n
2
·
G
β
·
(
1
+
T
β
·
s
)
·
δ
f
(
s
)
δ
(
s
)
(
2
)
L
A
(
s
)
δ
(
s
)
=
ω
n
2
s
2
+
2
·
ζ
·
ω
n
·
s
+
ω
n
2
·
G
LA
·
(
T
LA
2
·
s
2
+
T
LA
1
·
s
+
1
)
·
δ
f
(
s
)
δ
(
s
)
(
3
)
In the foregoing expression, γ is the yaw rate; β is the slip angle; LA is the lateral acceleration; ζ is the damping coefficient determined from the vehicle specifications and the vehicle speed; ω n is the eigenfrequency determined from the vehicle specifications and the vehicle speed; G γ is the yaw rate gain determined from the vehicle specifications and the vehicle speed; G β is the slip angle gain determined from the vehicle specifications and the vehicle speed; G LA is the lateral acceleration gain determined from the vehicle specifications and the vehicle speed; T γ is the yaw rate advancement time determined from the vehicle specifications and the vehicle speed; T β is the slip angle advancement time determined from the vehicle specifications and the vehicle speed; T LA1 is the lateral acceleration advancement time 1 determined from the vehicle specifications and the vehicle speed; T LA2 is the lateral acceleration advancement time 2 determined from the vehicle specifications; δ is the steering handle angle; and δ f is the front wheel steering angle.
The value δ/δ f is the steering gear ratio. For example, δ/δ f =18.1. In the case of two-wheel steering, when the steering handle is turned or operated, the front wheel steering angle is determined, so that the yaw rate, the slip angle and the lateral acceleration are determined.
FIG. 2 is a block diagram showing a construction of the A4WS-ECU in accordance with the first embodiment. In the case of four-wheel steering as in this embodiment, if the vehicle speed V, the steering handle angle δ, a target yaw rate γ* and a target slip angle β* are given to a computation portion 36 of the A4WS-ECU 18 , the front wheel steering angle δ f and the rear wheel steering angle δ r are determined.
FIG. 3 is a flowchart showing an operation of the vehicle steering control device in accordance with the first embodiment. This control operation is repeatedly executed at predetermined timing during a period from the turning on of the electric power source of the vehicle until the turning off thereof. As shown in FIG. 3 , in the case where the vehicle steering control device 10 of the embodiment is performing an arbitrary four-wheel steering control (S 11 ), the target yaw rate γ* and the target slip angle β* become as shown in the expressions (4) and (5) below.
EXPRESSION
2
γ
*
(
s
)
δ
(
s
)
=
G
γ
*
·
1
1
+
T
·
s
(
4
)
β
*
(
s
)
δ
(
s
)
=
G
β
*
·
1
1
+
T
·
s
(
5
)
At this time, the control rule of the target lateral acceleration LA* becomes as shown in the expression (6) below. As shown in FIG. 4 , the computation portion 36 of the A4WS-ECU 18 calculates a front wheel steering angle δ* f and a rear wheel steering angle δ* r corresponding to the target lateral acceleration LA*.
EXPRESSION
3
L
A
*
(
s
)
δ
(
s
)
=
V
(
γ
*
(
s
)
δ
(
s
)
+
s
·
β
*
(
s
)
δ
(
s
)
)
=
V
·
G
γ
*
+
G
β
*
·
s
1
+
T
·
s
(
6
)
Incidentally, in the expression (6), the relationship of the following expression (7) holds.
EXPRESSION 4
G* 62 ≠T·G* γ (7)
In the vehicle steering control device 10 of the embodiment, when the contribution of the target automatic control amount is less than or equal to the manual steering amount in the setting of the target steering amount, that is, when the manual control is equivalent or more dominant in the setting of the target steering amount than the automatic control, in other words, when the steering is based on the manual control, target values are prepared as in the foregoing expressions (4) to (6). During this state, the lateral shift and the turning of the vehicle become substantially equal in responsiveness. FIG. 6 is a Bode diagram showing a frequency response of the lateral acceleration of the control rule in accordance with the first embodiment. As shown in FIG. 6 , regarding a curve A of the frequency response of the lateral acceleration at the time of the manual steering, the higher the frequency, the lower the gain becomes, and the greater the phase delay becomes. In FIG. 6 , a curve 2 WS of the lateral acceleration of the two-wheel steering is also shown for reference.
As shown in FIG. 3 , when any of the CC control, the ACC control and the LKA control is on (YES in S 12 ), the vehicle steering control device changes the steering control rule to another so as to restrain the responsiveness in the turning of the vehicle and raise the responsiveness in the lateral shift of the vehicle (S 13 ). Or, the vehicle steering control device may change steering control rules so as to restrain the responsiveness in the turning and raise the responsiveness in the lateral shift when the vehicle speed becomes equal to or higher than 80 km/h.
In that case, the relationship of the following expression (8) is assumed to hold, and the expression (9) is obtained so that the responsiveness in the lateral shift becomes maximum. Then, the control rule of the target lateral acceleration LA** becomes as shown in the expression (10), so that as shown in FIG. 5 , the computation portion 36 of the A4WS-ECU 18 calculates a front wheel steering angle δ** f and a rear wheel steering angle δ** r corresponding to the target lateral acceleration LA**.
EXPRESSION
5
G
β
*
≠
T
·
G
γ
*
(
8
)
EXPRESSION
6
β
**
(
s
)
δ
(
s
)
=
T
·
G
β
*
·
1
1
+
T
·
s
(
9
)
EXPRESSION
7
LA
**
(
s
)
δ
(
s
)
=
V
·
(
G
γ
*
+
T
·
G
γ
*
·
s
1
+
T
·
s
)
=
V
·
G
γ
*
(
10
)
In this case, the phase delay of the lateral acceleration relative to the steering handle angle disappears, and the frequency response of the lateral acceleration becomes as shown by a curve B in FIG. 6 .
According to this embodiment, during the execution of the CC control, the ACC control or the LKA control, during which the contribution of the target automatic control amount is greater in the setting of the target steering amount than the contribution of the manual steering amount, that is, when the automatic control is more dominant in the setting of the target steering amount than the manual control, the A4WS-ECU 18 sets the target steering amount so as to better the responsiveness in the lateral shift relatively to the responsiveness in the turning, in comparison with when the contribution of the target automatic control amount is less than or equal to the manual steering amount in the setting of the target steering amount. When the contribution of the target automatic control amount is larger in the setting of the target steering amount than that of the manual steering amount, that is, when the vehicle is running under an automatic control, such as the CC control, the ACC control, the LKA control, etc., it is generally often the case that the responsiveness in the lateral shift is required more than the responsiveness in the turning during the execution of a constant-speed run control or the like. Therefore, since during the automatic control, the A4WS-ECU 18 sets the target steering amount so as to better the responsiveness in the lateral shift relatively to the responsiveness in the turning, the stabilization of the vehicle can be further improved and the driver can be caused to feel secured and comfortable during the automatic steering.
Particularly, in this embodiment, since during the automatic control, the A4WS-ECU 18 sets the target steering amount so that the phase delay of the lateral acceleration relative to the steering amount becomes small, it is possible to improve the responsiveness in the lateral shift during the automatic control.
A second embodiment of the invention will be described below. This embodiment is different from the first embodiment in that the responsiveness in the lateral shift is improved by changing control maps at the time of the automatic steering.
In this embodiment, as shown in FIG. 3 , in the case where the vehicle steering control device 10 of this embodiment is performing an arbitrary four-wheel steering control (S 11 ), if the target yaw rate δ* and the target slip angle β* are prepared as in the following expressions (11) and (12), the control rule of the target lateral acceleration LA* becomes as shown in the following expression (13).
EXPRESSION
8
γ
*
(
s
)
δ
(
s
)
=
ω
n
*
2
s
2
+
2
·
ζ
*
·
ω
n
*
·
s
+
ω
n
*
2
·
(
1
+
T
γ
*
·
s
)
·
G
γ
*
(
11
)
β
*
(
s
)
δ
(
s
)
=
ω
n
*
2
s
2
+
2
·
ζ
*
·
ω
n
*
·
s
+
ω
n
*
2
·
(
1
+
T
β
*
·
s
)
·
G
β
*
(
12
)
EXPRESSION
9
L
A
*
(
s
)
δ
(
s
)
=
V
·
(
γ
*
(
s
)
δ
(
s
)
+
s
·
β
*
(
s
)
δ
(
s
)
)
(
13
)
During this state, the lateral shift and the turning become substantially equal in responsiveness. As shown in FIG. 11 , regarding a curve C of the frequency response of the lateral acceleration at the time of the manual steering, the higher the frequency, the lower the gain becomes, and the greater the phase delay becomes.
Furthermore, as shown in FIG. 3 , if any of the CC control, the ACC control and the LKA control is on (YES in S 12 ), the control map is changed to another so as to restrain the responsiveness in the turning and raise the responsiveness in the lateral shift (S 13 ).
FIG. 7 is a diagram showing a control map of the yaw rate gain in accordance with the second embodiment, and FIG. 8 is a diagram showing a control map of the slip angle gain, and FIG. 9 is a diagram showing a control map of the slip angle advancement time. As shown in FIG. 7 , when any of the CC control, the ACC control and the LKA control is performed, the yaw rate gain is decreased to restrain the responsiveness in the turning. On the other hand, as shown in FIGS. 8 and 9 , the slip angle gain and the slip angle advancement time are increased to raise the responsiveness in the lateral shift when any of the CC control, the ACC control and the LKA control is performed.
The target yaw rate γ** and the target slip angle β** in the case where the control map has been changed become as shown in the following expressions (14) and (15).
EXPRESSION
10
γ
**
(
s
)
δ
(
s
)
=
ω
n
*
2
s
2
+
2
·
ζ
*
·
ω
n
*
·
s
+
ω
n
*
2
·
(
1
+
T
γ
*
·
s
)
·
G
γ
**
(
14
)
β
**
(
s
)
δ
(
s
)
=
ω
n
*
2
s
2
+
2
·
ζ
*
·
ω
n
*
·
s
+
ω
n
*
2
·
(
1
+
T
β
*
·
s
)
·
G
β
**
(
15
)
At this time, the control rule of the target lateral acceleration LA** becomes as shown in the following expression (16). As shown in FIG. 10 , the computation portion 36 of the A4WS-ECU 18 calculates a front wheel steering angle δ** f and a rear wheel steering angle δ** r corresponding to the target lateral acceleration LA**.
EXPRESSION
11
L
A
**
(
s
)
δ
(
s
)
=
V
·
(
γ
**
(
s
)
δ
(
s
)
+
s
·
β
**
(
s
)
δ
(
s
)
)
(
16
)
In this case, the phase delay of the lateral acceleration relative to the steering handle angle becomes less, and the frequency response of the lateral acceleration becomes as shown by a curve D in FIG. 11 .
According to this embodiment, during the execution of the CC control, the ACC control or the LKA control, during which the contribution of the target automatic control amount is larger in the setting of the target steering amount than the contribution of the manual steering amount, the A4WS-ECU 18 changes control maps so as to better the responsiveness in the lateral shift relatively to the responsiveness in the turning, in comparison with during the manual steering. Therefore, since during the automatic control, the A4WS-ECU 18 sets the target steering amount so as to better the responsiveness in the lateral shift relatively to the responsiveness in the turning, the stabilization of the vehicle can be further improved and the driver can be caused to feel secured and comfortable during the automatic steering.
A third embodiment of the invention will be described. This embodiment is different from the above-described first embodiment in that during the automatic steering, the responsiveness in the turning is restrained and the responsiveness in the lateral shift is raised by performing such a correction that the rear wheel steer angle becomes large on the basis of the LKA-ESP torque.
FIG. 12 is a block diagram showing a construction of an A4WS-ECU in accordance with the third embodiment. As shown in FIG. 12 , the A4WS-ECU 18 of this embodiment includes not only the computation portion 36 but also a correction coefficient-calculating portion 38 that calculates a rear wheel steer angle correction coefficient Z from the LKA-ESP torque output by the LKA-ECU 34 , and a final rear wheel steer angle-calculating portion 40 that calculates a final rear wheel steer angle DR from the rear wheel steering angle δ r calculated by the computation portion 36 . The final rear wheel steer angle DR calculated by the final rear wheel steer angle-calculating portion 40 is output to the rear steer ECU 26 , so that the rear steer actuator 28 is accordingly driven.
FIG. 13 is a flowchart showing an operation of the vehicle steering control device in accordance with the third embodiment. As shown in FIG. 13 , if the LKA control becomes on (S 22 ) from a state where the vehicle steering control device is performing an arbitrary four-wheel steering control (S 21 ), the correction coefficient-calculating portion 38 of the A4WS-ECU 18 calculates the rear wheel steer angle correction coefficient Z through a function of the rear wheel steer angle correction coefficient Z that uses the LKA-ESP torque as a parameter (S 23 ).
The final rear wheel steer angle-calculating portion 40 of the A4WS-ECU 18 calculates a final rear wheel steer angle DR using a correction expression DR=δr•(1+Z) from the rear wheel steering angle δ r calculated by the computation portion 36 , and the rear wheel steer angle correction coefficient Z calculated by the correction coefficient-calculating portion 38 (S 24 ).
The rear steer ECU 26 , after receiving the final rear wheel steer angle DR from the final rear wheel steer angle-calculating portion 40 , performs such a steering control as to change the rear wheel steer angle amount to an increased amount and thus restrain the responsiveness in the turning and raise the responsiveness in the lateral shift (S 25 ).
According to the embodiment, during the automatic control, the A4WS-ECU 18 sets the target steering amount so that the steering amount of the rear wheels becomes relatively large. Therefore, the amount of the turning is restrained and, on the other hand, the responsiveness in the lateral shift is further improved. Hence, the stabilization of the vehicle can be further improved, and the driver can be caused to feel secured and comfortable.
While embodiments of the invention have been described above, the invention is not limited to the foregoing embodiments, but may also be modified in various manners. | A vehicle steering control device capable of executing automatic steering and manual steering includes: an automatic control amount-setting device that sets a target automatic control amount based on information about vehicle behavior and ambient environment; a steering control amount-setting device that sets a target steering amount based on a manual steering amount input by a driver and the set target automatic control amount; and a steering device that steers based on the set target steering amount. When the target automatic control amount contributes more in the setting of the target steering amount than the manual steering amount does, the steering control amount-setting device sets the target steering amount so as to better the responsiveness in the lateral shift of the vehicle relatively to the responsiveness in the turning of the vehicle, in comparison with when the target automatic amount does not contribute more than the manual steering amount. | 1 |
FIELD OF THE INVENTION
The invention relates to sewing machines. More particularly, the invention relates to sewing machines adapted for overcast stitching of thick materials.
BACKGROUND OF THE INVENTION
Industrial sewing machines have long been used for sewing together relatively thick materials such as mattress cover$ and upholstery. Sewing machines used for sewing such thick materials must be adapted to provide adequate vertical clearance for the material to fit through the throat of the machine. The throat plate, the plate upon which the material rests as it is sewed, defines the bottom plane of the space in which the material must fit in the throat of the machine. Accordingly, the thickness of the material which can be sewn by the machine is dictated by the clearance between the throat plate and the lowest of the upper travel limit of the 1) needle, 2) presser foot and 3) upper walking foot. Although the needle, presser foot and upper walking foot must provide an unusually large clearance when at their upper travel limit, the needle must still be able to plunge below the throat plate to place a stitch in the material. Accordingly, the needle's throw (i.e., the distance traveled by the needle from the top of its motion to the bottom) on such a machine must also be unusually long. If the machine is to be able to be used with thin as well as thick materials, the same is true of the throw of the presser foot and the upper walking foot. The presser foot and upper walking foot must be able to get very close to the throat plate in order to contact very thin materials but also must be able to provide larger clearance for very thick materials.
Typically, the lower travel limit of the presser foot in a sewing machine is limited by contact of the presser foot with the throat plate. However, this manner of limiting motion is undesirable because the impact of the presser foot with the throat plate causes unnecessary wear and tear on the components of the device. It is also desirable to be able to adjust the downward force of the presser foot on the material in order to accommodate for materials of different thickness.
In sewing machines which comprise upper walking feet, the upper walking foot is typically positioned directly over the lower walking foot so that the material is "clamped" between the upper and lower walking feet. U.S. Pat. No. 4,449,464 discloses a sewing machine including upper and lower walking feet. Some sewing machines also include a secondary (or rear) lower walking foot spaced rearwardly of the upper walking foot and primary lower walking foot. Reference is made to U.S. Pat. Nos. 4,166,422, 3,995,571 and 3,530,809 as examples of sewing machines comprising mating upper and lower walking feet and an additional secondary lower walking foot spaced rearwardly away from the other walking feet. In certain sewing situations, it is desirable for the various walking feet to move at different speeds relative to one another. This is typically useful where one wishes for the material to bunch as it is sewed. For instance, when bunching of the material is desired, the forward lower walking foot should move at a speed slower than the rearward lower walking foot. Forward is defined herein as the direction in which the material is advanced as it is sewn. In fact, in certain applications, it is desirable for the upper walking foot to travel at a different speed than the primary lower walking foot (which it is directly above), thus causing the upper layer of material to travel at a different speed than the lower, causing only one of the layers to bunch as it is sewed.
In overcast stitching, thread is wrapped once around the edge of the material for each stitch. In machines adapted for performing overcast stitching, two strands of thread, an upper strand which is looped through an eye in the tip of the needle and a lower strand which is looped through a looper below the throat plate, are intertwined to form the overcast stitches. The stitch will not be described herein as it is conventional in the art and not material to the present invention except insofar as improvements have been made to certain mechanical components of an overcast stitching sewing machine. Accordingly, the following discussion of overcast stitching is not intended to be complete but simply describes the necessary machine components for accomplishing overcast stitching.
FIGS. 1A 1B and 1C illustrate the movement of the needle, looper and spreader of an overcast stitching sewing machine through one stitch cycle. The strands of thread are not shown for ease of illustration. When the tip of the needle 70 is plunged below the throat plate 11, as shown in FIG. 1A, a looper 183, rotating about axis 187 in the direction of arrow 65, passes close by the needle tip and traps the upper thread from needle 70 underneath arm 183a. Looper 183 transports the trapped thread horizontally beyond the edge of the material 77 as the needle continues its stroke and begins moving upwardly, as illustrated in FIG. IB. When the looper reaches beyond the edge of the material (FIG. 1B), spreader 180, moving upwardly, grabs the lower thread from looper 183 by trapping it in fork 182 and transports it around the edge of the material bringing it up and over the material and positioning it adjacent the tip of needle 70 as the needle reaches the top of its throw and begins its downward stroke again (FIG. 1C). The needle removes the thread from the spreader by trapping it between the needle tip and the upper thread strand which passes through the eye 67 in the needle tip. At the moment when the thread is trapped by needle 70, spreader 180 reaches the top of its stroke and reverses direction, moving downwardly and to the right, releasing the thread from fork 182. The needle then plunges through the material transporting the thread grabbed from the spreader through the material causing a stitch to be formed over the edge of the material returning to the position shown in FIG. 1A. The apparatus then repeats the cycle to make the next stitch.
Commonly, an overcast stitching machine is also provided with a knife system comprising upper and lower knives which cut the material just before it is advanced through the sewing area so as to form the edge close to the needle and parallel to the stitching. The knife assembly is rearwardly of the sewing area and typically comprises a stationary lower knife and a reciprocating upper knife which moves up and down to meet with the lower knife during the lower portion of its travel to act as a scissor to cut the material before it is advanced into the sewing area.
Accordingly, it is an object of the present invention to provide an improved sewing machine.
It is a further object of the present invention to provide a sewing machine with a very large vertical clearance between the throat plate and the upper travel limits of the needle, presser foot and upper walking foot.
It is yet another object of the present invention to provide a sewing machine with variable speed walking feet.
It is yet another object of the present invention to provide a sewing machine in which the lower travel limit of the presser foot is adjustable relative to the throat plate.
It is a further object of the present invention to provide a sewing machine in which the downward force of the presser foot can be set to any desired force.
It is another object of the present invention to modify existing sewing machines to improve their utility.
It is yet one more object of the present invention to provide an overcast stitch sewing machine having high clearance for accepting thick materials and having an increased throw and upper travel limit of the spreader.
SUMMARY OF THE INVENTION
The invention comprises a sewing machine that is particularly adapted for overcast stitching thick materials. The invention, however, can be adapted to other types of sewing machines.
The present invention resides partially in improvements which can be made to an existing sewing machine, and particularly the Model 515-4-26 sewing machine sold by Pfaff Pegasus of U.S.A. of Atlanta, Ga., in order to allow it to accept thicker materials than the original machine. The invention, however, comprises improvements which can be made to any machine. Further, certain aspects of the invention comprise inventive apparatus which can be embodied in any sewing machine.
The sewing machine of the present invention comprises a biasing assembly for biasing the presser foot downwardly towards the throat plate to firmly hold the material stationary while the needle is in the material. The biasing assembly may comprise a fixed tubular housing containing first and second helical die springs and three spacers with longitudinal flanges which extend inside the helical die springs and prevent them from bending or collapsing internally. Spacers of varying length can be employed depending on the desired force of the downward bias. A preload spacer is in contact with the roof of the tubular housing. The preload spacer is followed by a first spring, a second spacer, a second spring and then a third spacer adapted to engage, at its lower end, an arm connected to the presser foot. The bottom of the tubular housing is adapted to threadedly accept a cap nut at its lower end. The cap nut has an opening in its end through which the upper end of the rod on which the presser foot is mounted extends into the tubular housing. The upper end of the presser foot rod includes an outwardly extending flange so that the upper end of said presser foot arm cannot pass through the opening, but the remainder of the rod can slide freely in the opening. The lower limit of the throw of the presser foot is limited by the cap nut. The lower limit of travel of the presser foot can be adjusted by the number of revolutions that the cap nut is screwed into the threaded tubular housing. A cushion such as a urethane pad is fixed to the inner surface of the cap nut so as to cushion the impact of the outwardly extending flange of the presser foot rod when it strikes the cap nut.
According to another aspect of the invention, the machine comprises forward and rear lower serrated walking feet and an upper serrated walking foot. All of the walking feet have elliptical cycles such that they come in contact with the material lying on the throat plate as they are moving forward and thus grab the material and advance it between needle strokes. The upper walking foot is positioned directly above the forward lower walking foot. Both lower walking feet travel in elliptical motion rising above the throat plate near the top of their motion to engage the material and feed it forward. The upper walking foot has clockwise elliptical motion and engages the material from above during the lower portion of its travel. Although both lower walking feet are driven by the same reciprocating shaft, the speed of the rear lower walking foot is adjustable relative to the speed of the forward lower walking foot. This is accomplished by making the moment arm coupling the rear walking foot to the drive shaft adjustable in length. In the present invention, the upper walking foot also has variable speed relative to the forward lower walking foot (to which it is adjacent) by virtue of being connected to the same moment arm as the rear lower walking foot.
To increase the throat clearance of the sewing machine, the needle housing is raised. The needle drive shaft and, through the needle drive shaft, the needle, presser foot and upper walking foot, are mounted to the needle housing. The needle housing is raised by insertion of a trapezoidal wedge between the needle housing and the lower housing. The upper and lower surfaces of the wedge are angled such that the needle housing is tilted 4° from its original orientation. The needle guide tube, through which the needle travels, is also mounted to the needle housing. Accordingly, the angle of the needle is also changed 4°. The angle change is necessary because, in certain types of sewing machines, the needle is angled slightly from the vertical position. If the needle height is raised without changing its angle, the needle will traverse a course parallel to its original course but displaced in a direction perpendicular to the direction of motion of the needle. Since the direction of the motion of the needle is not vertical, this displacement includes a horizontal component. This horizontal displacement, without angle correction, would cause the needle to no longer meet with the looper or spreader at the same points. Accordingly, the trapezoidal wedge imparts an angle change to the path of travel of the needle as required to cause the needle to meet with the looper and spreader.
According to another aspect of the invention, the throw of the spreader of this machine is increased by replacing a single arm connecting the vertical spreader shaft to a horizontal drive shaft with a multiple arm arrangement in order to increase the throw of the spreader without significantly increasing the horizontal distance between the horizontal drive shaft and the vertical spreader shaft. In one possible embodiment, the single arm is replaced with two shorter, overlapping arms. One end of the first arm is connected to the drive shaft and the other end is connected to the second arm at a point intermediate the ends of the second arm. The second arm is coupled to the spreader shaft at one end The other end of the second arm is pivotally fixed at a point between the drive shaft and the spreader shaft. As the drive shaft rotatedly reciprocates, the end of the second arm which is coupled to the spreader shaft travels a greater vertical distance than if a single arm linkage of the same length was used. Accordingly, the spreader shaft and spreader travel a greater vertical distance. The length of the spreader shaft has been increased so that the increased throw does not change the lower limit of the throw of the spreader shaft. Accordingly, the additional throw achieved by the above-described double arm arrangement is manifested as an increase in the upper travel limit of the spreader while the lower travel limit of the spreader remains the same.
Additionally, the machine comprises upper and lower knives for scissoring off the edge of the material as it is advanced through the machine. The lower knife is stationary while the upper knife is mounted to a reciprocating shaft by an arm causing the knife to travel in an arc and meet the lower knife during the lower portion of its travel. In order to create room for the lengthened spreader shaft, the knife arm was rotated upwardly on the shaft. In order to cause the upper knife to still mate with the lower knife and not interfere with the operation of the spreader, a spacer was added at the end of the knife arm to position the knife further rearwardly and lower it back down to almost its original height. The lower knife holder was replaced with a new holder which positions the lower knife further rearwardly also so that it still mates with the upper knife.
Since the needle was raised by the addition of the wedge, its throw had to be increased so that it still plunged below the throat plate to meet with the looper. The needle is driven by a reciprocating needle drive shaft in the needle housing. The needle drive shaft itself is driven by a generally vertical connecting member which is connected at its upper end to the needle drive shaft via a connecting arm and at its other end to the main reciprocating drive shaft in the lower housing. The connecting member is lengthened to accommodate the increased distance between the main drive shaft and needle drive shaft caused by the addition of the wedge. Further, the throw of the needle was increased by shortening the arm connecting the vertical connecting member to the needle drive shaft. Accordingly, the same amount of vertical travel of the vertical connecting member produces greater rotation of the needle drive shaft. The needle drive shaft diameter at the point where it is coupled to the arm is reduced from the nominal shaft diameter to accommodate the now closer drive bar which would otherwise strike the original diameter needle drive shaft and prevent the machine from operating.
The clearance of the presser foot over the throat plate has been increased by lengthening the arms which urge the presser foot upwardly when the needle exits the material.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A, 1B and 1C are side views illustrating the relative positions of the needle, looper and spreader of an overcast stitching sewing machine in three successive states comprising the stitch cycle of such a sewing machine.
FIG. 2 is a simplified side view of the sewing machine of the present invention in partial cross-section illustrating the presser foot biasing structure of the present invention.
FIG. 3 is perspective view illustrating a trapezoidal wedge used to increase the clearance of the needle, presser foot and upper walking foot of the sewing machine of the present invention.
FIG. 4 is side view illustrating the relative relocation of the needle accomplished by the insertion of the wedge shown in FIG. 2 in the sewing machine of the present invention.
FIG. 5A is a simplified cut away side view of the mechanism for operating the presser foot, needle, and walking feet of the sewing machine of the present invention when the machine is in a first condition.
FIG. 5B is a simplified cut away side view of the mechanism for operating the presser foot, needle, and walking feet of the sewing machine of the present invention when the machine is in a second condition.
FIG. 6 is a perspective view of the lower walking feet and walking feet mechanism of the present invention shown in more detail than in FIGS. 5A and 5B.
FIGS. 7A and 7B are simplified cut away side views showing the mechanism for driving the needle drive shaft in the present invention at two different instances during the drive cycle.
FIG. 8A is a cut away side view of the mechanism for operating the spreader of the sewing machine of the present invention showing the spreader in a first position.
FIG. 8B is a cut away side view of the mechanism for operating the spreader of the sewing machine of the present invention showing the spreader in a second position.
FIG. 9A is an exploded perspective view of the edging knife assembly of the present invention.
FIG. 9B is a side view of the knife assembly of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention reside partially in improvements which can be made to an existing sewing machine and particularly the model 515-4-26 sewing machine sold by Pfaff Pegasus of U.S.A. of Atlanta, Ga. (hereinafter Pegasus sewing machine) in order to increase the clearance between the throat plate and the upper travel limits of the presser foot, needle and upper walking foot so that the machine can accommodate thicker materials. However, the invention comprises improvements over the sewing machine art in general.
FIG. 2 is a simplified side view, in partial cross-section, of a mechanism for causing the presser foot of a sewing machine to reciprocate in vertical motion so as to clamp the material to the throat plate when the needle is in the material and to rise and release the material when the needle exits the material so that the material can be advanced by walking feet before the next stitch. The presser foot 12 is permanently biased downwardly by a biasing mechanism 10. Means are provided for manually lifting the presser foot (and upper walking foot) prior to operation in order to initially insert the material to be sewed in the throat of the machine. A hydraulic cylinder 29 can be manually operated to raise the presser foot 12. Shaft 31 is coupled to presser foot connecting member 14 via arms 33 and 35. Connecting member 14 may be a cylindrical rod. Upon activation, shaft 31 is extended out of hydraulic cylinder 29 causing arm 33 to rotate counter clockwise about pivot 41 thus lifting arm 35. End 35b of arm 35 extends below a flange 14c on rod 14 and lifts presser foot rod 14 and presser foot 12 by exerting an upward force on flange 14c. Arm 35 is slotted at 35a. A pin 43 is fixedly attached to a wall behind arm 35 and extends through slot 35a. Thus, arm 35 can slide up and down and rotate about pin 43. As will be explained in greater detail with respect to FIGS. 5A and 5B, the upper walking foot is coupled to rod 14 via linkages 42 and 162 such that the lifting of presser foot rod 14 also lifts the upper walking foot.
During sewing operation, the presser foot is urged upwardly at fixed intervals by a reciprocating drive shaft 36 as will be described in greater detail herein. The presser foot biasing mechanism 10 is shown in cross-section in FIG. 2. The presser foot 12 is coupled to rod 14 by means of a presser foot arm 16. Rod 14 is biased downwardly by biasing means such as helical die springs 18 and 20 contained in tubular housing 22. Housing 22 includes upper cap nut 24 and lower cap nut 26. The ends of housing 22 are externally threaded so that the internally threaded cap nuts 24 and 26 can be screwed onto the opposing ends of housing 22. Roof 24a of upper cap nut 24 is solid. Floor 26a of lower cap nut 26 comprises an opening 26b through which rod 14 slideably travels. The upper portion of rod 14 includes a transverse flange 14a which is wider than opening 26bsuch that the flange cannot pass through hole 26b, thereby trapping the upper portion of rod 14 within the presser foot biasing mechanism 10. A longitudinal flange 14b extends upwardly from rod 14 and fits within a slot in spacer 28. Spacer 28 includes a longitudinal flange 28a which extends upwardly through the center of helical spring 23. A second spacer 30 is positioned between helical springs 18 and 20 and has opposing flanges 30a and 30b extending therefrom through the centers of springs 18 and 20, respectively. A preload spacer 32 is positioned between the upper end of spring 18 and roof 24a of upper cap nut 24. Longitudinal flange 32a extends from preload spacer 32 through the center of helical spring 18.
Floor 26b of cap nut 26 defines the downwardmost position of presser foot arm 14 and thus presser foot 12. The spring lengths and spacer lengths are chosen such that the springs are at least slightly compressed when transverse flange 14a of rod 14 is in its downwardmost position in which flange 14a abuts against the floor 26b of bottom cap nut 26. A cushioning member such as polyurethane pad 34 is attached to the inner surface of floor 26b so as to cushion the impact of flange 14a against the floor 26b.
Longitudinal flanges 28a, 30a, 30b and 32a of the spacers 28, 30 and 32 assist in preventing the springs from bending since they extend through the center of the helical springs. Accordingly, the longitudinal flanges 28a, 30a, 30b and 32a should be as long as possible.
The length of the flanges, however, is limited by the uppermost possible position of rod 14. That is, for instance, if the spring is compressed enough, the top part of flange 28a will hit the bottom part of flange 30b. Accordingly, these flanges must be short enough such that they will not prevent the rod 14 from reaching what would otherwise be its uppermost possible position.
Since upper cap nut 24 can be easily removed from the tubular housing by unscrewing it, preload spacer 32 can be replaced quickly with a spacer of a different length when it is desired to change the downward compressor force of presser foot 12 as, for instance, may be the case when significantly changing the thickness of the material which is being sewed. As the material becomes increasingly thicker, the downward pressure of presser foot 12 on the material increases because the spring will be compressed more when presser foot 12 is resting on top of the material. Accordingly, in such a situation, if the force is too great, preload spacer 32 can be replaced with a shorter preload spacer thus reducing the compression of the springs. In fact, since upper cap nut 24 is removable the springs themselves can be easily replaced if desired.
Further, the lower travel limit of presser foot 12 is limited by the position of floor 26b of lower cap nut 26 and the thickness of polyurethane pad 34. Accordingly, by proper positioning of floor 26b, presser foot 12 can be prevented from crashing into the throat plate 11, thus reducing wear of the components of the machine. Since lower cap nut 26 is engaged to housing 22 by thread means, the height of floor 26b can be adjusted by screwing or unscrewing lower cap nut 26 to the desired extent.
FIG. 3 illustrates another aspect of the improvements made to the Pegasus machine. FIG. 3 is a perspective view of the sewing machine illustrating the trapezoidal wedge 50 used to increase the throat clearance of the sewing machine. Wedge 50 is also shown in cross section in FIGS. 7A and 7B. In accordance with the present invention, wedge 50 is inserted between the needle housing 52 and the main housing 54. The needle guide shaft, the hollow tubular shaft through which the needle travels, as well as the needle drive shaft 36 are fixedly attached to the upper housing. The needle guide shaft does not appear in FIG. 3, but is shown in FIGS. 5A and 5B and is designated with reference number 81. The raising and tilting of needle housing 52 by the insertion of trapezoidal wedge 50, thus raises and tilts the needle.
As illustrated in FIG. 4, in the original Pegasus sewing machine, the needle is angled from the vertical by approximately 20°. Thus, if the height of the needle is raised without changing the angle of the needle, the needle will travel in a path along line 5 in FIG. 4 parallel to its original path along line 3 but displaced therefrom by a predetermined distance perpendicular to the original path. The upper travel limit of the needle tip (as well as the lower travel limit) is raised by height h in FIG. 4. However, if the angle of the needle is not changed, the needle will not meet the spreader or the looper in the original locations. The shift in the needle path is not too significant with respect to meeting with the looper. The looper typically has a fairly long horizontal throw and will still be able to catch the thread off of the needle, particularly if the throw of the needle is increased so that the lower travel limit of the needle is not significantly changed in the vertical direction from the original needle path.
However, the relative position of the needle and spreader when they are to exchange thread must be maintained to a fairly high tolerance. As will be described herein in greater detail with respect to FIGS. 8A and 8B, the path of the spreader has also been modified in the present invention such that the spreader should now meet the needle at point 62 as opposed to point 61. As shown in FIG. 4, point 62 would not be on the path traversed by the needle if its angle was not changed. In order to cause the needle to still meet with the spreader within acceptable tolerance limits, the angle of the needle must be reduced about 4° from the vertical. Accordingly, the side cross-section of wedge 50 (as shown in FIGS. 7A and 7B) instead of being square, is trapezoidal, with the upper surface 50a angled about 4° relative to the bottom surface 50b.
FIGS. 5A and 5B are simplified cut away side views of the sewing machine of the present invention at two different stages. FIGS. 5A and 5B are greatly simplified to ease the understanding of the invention. For instance, FIGS. 5A and 5B do not show the looper or the spreader. FIG. 6 is a simplified perspective view of some of the components in lower housing 54 of FIGS. 5A and 5B. In FIG. 5A, the needle is withdrawn from the material and the presser foot 12 is not engaged with the material. At this moment, upper walking foot 72 and lower walking feet 74 and 76 are engaged with the material and moving leftward in the figure. In FIG. 5B, the needle is in the material, the presser foot is clamping the material down to the throat plate and the upper and lower walking feet 72, 74 and 76 are not engaged with the material and are moving towards the right.
The desired cyclical movement of the needle, presser foot and all walking feet will be described at first without reference to the mechanical structure for causing the movement.
In general, one or more layers of material 77 are laid on the throat plate 11. Presser foot 12 is biased downwardly onto the upper surface 77a of the material and presses the material against throat plate 11. At this time, upper walking foot 72 is in its raised position so that it is not in contact with the material. Lower walking feet 74 and 75 are below the throat plate so that they do not engage the material. Presser foot 12 remains pressed against material 77 as the needle 70 advances in and through the material 77. Near the bottom of its travel limit, when the tip 60 of the needle is below the throat plate 11, a looper (not shown in FIGS. 5A and 5B) passes closely by the tip 60 of the needle to partially complete the stitch in a manner which is known in the art.
At essentially the same moment that the needle tip 60 exits from the material during its upward stroke (i.e., the point where the tip 60 of needle 70 is even with bottom surface 12a of presser foot 12), presser foot 12 begins to rise off of the material. Simultaneously, upper walking foot 72 lowers and lower walking feet 74 and 76 raise to engage the material. All of walking feet 72, 74 and 76 travel in elliptical paths illustrated by arrows 72a, 74a and 76a, respectively, in FIG. 5A such that when the walking feet are engaging the material, they are moving in the forward direction (i.e., to the left in FIGS. 5A and 5B) and thus advance the material. Due to the elliptical motion of the walking feet, they eventually disengage the material 77 and begin traveling rearward to be prepared to advance the material after the next stitch. Just before the walking feet disengage the material, presser foot 12 once again lowers into contact with the material starting the cycle all over again.
The mechanism for causing all of this action to occur at the appropriate instances will now be described in detail with respect to FIGS. 5A, 5B and 6. Primary lower walking foot 74 is coupled via arm 80 to primary lower walking foot bar 82. Secondary lower walking foot 76 is coupled via arm 86 to secondary lower walking foot bar 84. In the view of FIGS. 5A and 5B, bar 82 is directly behind, and therefore obscured by, bar 86. Both bars can be seen in FIG. 6.
The vertical component of the motion of primary lower walking foot 74 is provided by walking foot drive shaft 88 via arm 93 and linkage 95. Drive shaft 88 is driven to reciprocate approximately 1/4 of a revolution by main drive shaft 167 via arms 151 and 153 and off center sub shaft 155. This causes arm 93 to rock back and forth as illustrated by arrows 96. One end of linkage 95 is coupled to arm 93 at pivot 110 while the other end is coupled to primary walking foot bar 82 by pivot shaft 99 which is fixedly attached to bar 82 at one end and pivotally attached to linkage 95 by pivot 98 at the other end. End 102 of bar 82 comprises a slot 104 through which passes a fixed guide bar 106. Guide bar 106 fixes end 102 of bar 82 vertically, however, slot 104 allows bar 82 to slide horizontally relative to guide bar 106. Bar 82 slides horizontally in response to the motion of the walking foot drive shaft 88 transmitted to bar 82 via arm 93 and linkage 95.
Secondary lower walking foot bar 84 is driven off of shaft 88 via a second arm 90 and linkage 100. However, whereas in the primary lower walking foot mechanism, pivot 110 on arm 93 is fixed at a specified distance from drive shaft 88, in the secondary lower walking foot mechanism, pivot point 100 connecting arm 90 to linkage 92 is adjustable. The specific mechanism utilized for adjusting pivot point 100 is not shown for ease of illustration. However, it should be understood that mounting box 112 can be loosened and slid up or down on arm 90 and then re tightened to fix pivot point 100 at the desired distance on arm 90 from shaft 88. In this manner, the speed of secondary lower walking foot 76 can be changed relative to the speed of primary lower walking feet 74. This is the result of simply making the moment arms (i.e., the distance between the drive shaft 88 and the pivots 100 and 110) different. For instance, if the moment arm of the secondary walking foot is longer than the moment arm of the primary lower walking foot, then, for any given rotation of the drive shaft 88, pivot point 100 (and thus walking foot 76) will traverse a greater distance than pivot point 110 (and thus walking foot 74). Accordingly, secondary lower walking foot 76 will traverse a greater distance than primary lower walking foot 79 in the same period of time (i.e., it will travel faster).
As previously noted, the motion of walking feet 74 and 76 is not strictly horizontal but is elliptical, having a small vertical component. The vertical component of the motion of lower walking feet 74 and 76 is provided by off center sub shaft 157 of main drive shaft 167. Unlike the other drive shafts discussed herein, main drive shaft 167 does not reciprocate but simply rotates in a clockwise direction. Blocks 147 and 149 are mounted on off center sub shaft 157 and are positioned within horizontal slots 111 and 113 of bars 82 and 84, respectively. The rotation of main drive shaft 167 causes sub shaft 157 and blocks 147 and 149 to travel in circles. The vertical component of the circular motion of blocks 147 and 149 is transmitted to bars 82 and 84. The horizontal component of their motion is not transmitted to the bars since blocks 147 and 149 can slide horizontally in slots 111 and 113, respectively.
The horizontal component of the elliptical motion of upper walking foot 72 is provided by connection of upper walking foot 72 via linkage 118 and arm 120 to secondary lower walking foot bar 84. As shown in FIG. 5A, linkage 118 is pivotally coupled to arm 120 by pivot 122. The other end of arm 120 is fixedly connected to bar 84 by pivot 124. Accordingly, as bar 84 moves horizontally, so does arm 120 and, consequently, linkage 118 and upper walking foot 72.
Due to the limited space available in the machine, a slot 132 was cut through primary lower walking foot arm 82 through which arm 120 passes. The slot is long enough to allow arm 120 to slide horizontally therein because secondary lower walking foot bar 84, to which arm 120 is rigidly attached, can move at a different rate of speed and traverse a different distance than arm 82, as previously discussed.
The motion of presser foot 12 and needle 70 as well as the vertical component of the motion of upper walking foot 72 now will be described in detail in relation to FIGS. 5A, 5B, 7A and 7B. Needle assembly 71 comprises needle 70, which is attached to a first needle bar 140, which, in turn, is attached to a second needle bar 142 of larger diameter. The needle assembly 71 is driven up and down by reciprocating needle drive shaft 36 via arm 146 and linkages 148 and 150. Arm 146 is rigidly attached to the drive shaft 36. Connection points 152 and 154 are pivots. Needle drive shaft 36 further drives presser foot 12 (upwardly only, since presser foot 12 is permanently biased downwardly by assembly 10) via arm 38, and linkages 40 and 42. Arm 38 is fixedly mounted to shaft 36. Connecting points 144, 158 and 160 are pivoting points. Point 160 is coupled to presser foot rod 14, which in turn is rigidly coupled to presser foot 12 via presser foot arm 16. Needle drive shaft 36 also provides the vertical component of the elliptical motion of upper walking foot 72 via arm 138, linkages 40, 42 and 162 and arm 118. Connections 164 and 168 are pivots.
As discussed with respect to FIGS. 2 and 3, the height of the needle 70 has been increased by the addition of a trapezoidal wedge between the needle housing and the lower housing. Consequently, the throw of needle 70 had to be increased so that it still extends below the throat plate at the bottom of its throw to meet with the looper. The throw of needle 70 is increased in the present invention by increasing the rotation of needle drive shaft 36. The driving mechanism for causing needle drive shaft 36 to rotate is not shown in FIGS. 5A and 5B. Instead reference is made to FIGS. 7A and 7B which are side views of the needle drive shaft and selected related components. Needle drive shaft 36 itself is driven off of the main drive shaft 167 via connecting member 166. The bottom of connecting member 166 is attached to main drive shaft 167 via off-center pivot 170. The rotation of main drive shaft 167 drives member 166 up and down in primarily vertical motion. Needle drive shaft 36 is driven by the vertical motion of the upper end 172 of connecting member 166 via arm 174. Arm 174 is fixedly attached to needle drive shaft 36 and pivotally attached to connecting member 166 by pivoting connection 178. The rotation of needle drive shaft 36 has been increased in accordance with the present invention by replacing the original arm coupling connecting member 166 to drive shaft 36 with the much shorter arm 174. Accordingly, the same vertical travel of connecting member 166 produces a greater rotation of shaft 36. In order to accommodate the much closer proximity of the upper end 172 of connecting member 166 to needle drive shaft 36, the diameter of needle drive shaft 36 arm 174 was reduced in the vicinity of arm 174 so as to prevent connecting member 166 from striking shaft 36 at the top of its motion. The original circumference of shaft 36 is shown by dotted circular line 175 in FIGS. 7A and 7B. As can be seen in FIG. 7A, when connecting member 166 is in its uppermost position, the inner side surface 166a of connecting member 166 would have contacted the needle drive shaft of original circumference (circular line 175). Accordingly, drive shaft 36 was reduced in diameter in the vicinity of arm 174 and connecting member 166 to have the circumference illustrated by solid circular line 36a.
In FIGS. 7A and 7B, arm 146 and related components for driving the needle as well as arm 38 and related components for driving the presser foot are shown in phantom. It should be understood that these components are displaced perpendicular to the surface of the page from connecting member 166, and arm 174 and, in the Pegasus sewing machine, are actually separated from each other by a plate through which the needle drive shaft 36 passes (see FIG. 3b, for instance). It should also be understood that the diameter of drive shaft 36 has not been changed at the point where arms 146 and 38 are coupled to it.
Connecting member 166 was also lengthened to accommodate for the raising of needle drive shaft 36 by the insertion of wedge 50 between the two housings.
Returning to FIGS. 5A and 5B, presser foot 12 is permanently biased downwardly by spring assembly 10 as previously described. When needle drive shaft 36 rotates in the counter-clockwise direction, an upward force is exerted on presser foot rod 14 by needle drive shaft 36 via arm 38 and linkages 40 and 42. As can be seen in FIG. 5A, when upper walking foot 72 meets the upper surface 77a of the material 77, walking foot 72 presses down against the material until a predetermined force is exerted and the downward force of foot 72 is cancelled out by the upward force of throat plate 11 and material 77. At this point, the downward motion of foot 72 and thus arm 118 is halted. This, in turn, cause pivot point 164 to become almost stationary (linkage 162 actually can rotate very slightly when arm 118 is stationary). After this condition is reached, further clockwise motion of needle drive shaft 36 continues to force pivot point 158 on linkage 42 downward. However, since point 164 is essentially fixed in space, arm 42 rotates counterclockwise around point 164, thus causing pivot point 160 at the opposite end of linkage 42 to rise. Pivot point 160 is coupled to presser foot rod 14. Accordingly, presser foot rod 14 (and presser foot 12) are forced upwardly to disengage the material. Accordingly, presser foot 12 does not begin to travel upwardly off of top surface 77a of material 77 until walking foot 72 engages the material. The length of the various linkages and arms are selected such that the needle has also disengaged the material at this point so that the walking feet advance the material (to the left in FIGS. 5A and 5B) only after the needle (and presser foot) have disengaged from the material.
Referring now to FIG. 5B, as the needle 70 plunges back into the material 77, a similar but opposite action occurs to that described above. When needle drive shaft 36 reaches the end of its counterclockwise reciprocation, it begins to rotate clockwise again urging needle 70 downwardly via arm 146 and linkages 148 and 150. This clockwise rotation of shaft 36 also causes linkage 42 to begin rotating clockwise around pivot point 164 urging presser foot 12 downwardly and eventually back into contact with the top surface 77a of the material. When the downward motion of presser foot 12 is halted by material 77, pivot point 160 at the end of arm 42 becomes fixed in space. Accordingly, at the point where the downward motion of presser foot 12 is halted by contact with the material, arm 42 continues to rotate in the clockwise direction, but it rotates about pivot point 160 instead of pivot point 164. Accordingly, pivot point 164 now begins to rise thus lifting upper walking foot 72 off of the material via linkage 162 and upper walking foot arm 118.
As noted above, needle drive shaft 36 has been raised by the addition of the wedge shown in FIG. 2. Accordingly, the maximum clearance of not only the needle but also the presser foot and the upper walking foot have been increased. The maximum clearance of the presser foot 12 increases as linkages 40 and 162 increase in length. Essentially, increasing the lengths of linkages 40 and 162 produces an increase in the throw of the presser foot which translates at least partially into an increase in its upper travel limit. The lower travel limit of presser foot 12 is dictated by the material 77, the throat plate 11, or the lower cap nut 26 of spring assembly 10, whichever is highest.
FIGS. 8A and 8B illustrate improvements made to the spreader assembly in accordance with the present invention. As previously noted, spreader 180 comprises a fork 182 at its end which grabs thread off of a looper 151 when the spreader is near its lower travel limit (the position illustrated in FIG. A) and transports it around the edge of the fabric and over the fabric to meet the needle 70 near the top of the spreader's and the needle's travel limits (as illustrated in FIG. 8B). The spreader 180 is mounted on a spreader shaft 186 which slidingly passes through a hole 188 in guide 190. Guide 190 is attached to the lower housing by shaft 192 and can rotate on shaft 192. The motion of spreader fork 182 is essentially vertical until the very top of its throw where a slight arc is introduced as illustrated by arrow 194 in FIG. 8B so that the fork 182 will be adjacent the needle and the needle can engage the thread held in fork 182.
Spreader 180 is driven by reciprocating spreader drive shaft 198. In the base Pegasus sewing machine, drive shaft 198 is connected to the bottom of spreader shaft 186 by a single arm. In the present invention, that arm has been replaced by a multiple arm structure such as the double arm structure shown in box 184 in FIG. 8A. An arm 200, shorter than the original arm, is rigidly attached to drive shaft 198 at 202. The opposite end of arm 200 is attached to one end of a transverse connecting bar 204. The other end of connecting bar 204 fits through a hole 206 intermediate the ends of a second arm 208. Connecting bar 204 can rotate in hole 206. Shaft 210 fits through hole 212 in the end of second arm 208. Shaft 210 can rotate in hole 212. The other end of shaft 210 is fixed to the lower housing 54 by eccentric plug 214. Eccentric plug 214 can be rotated before being welded to housing 54 to adjust the exact position of shaft 210. The other end of arm 208 is coupled to the spreader shaft 186 by connecting member 216.
FIG. 8A shows the position of the spreader structure when shaft 198 is rotated to its furthermost counterclockwise position. As the shaft rotates clockwise from this position, arm 200 rotates clockwise raising connecting bar 204 in an upward arc. The raising of bar 204 causes arm 208 to rotate about shaft 210. As shown in FIG. 8B, the structure in box 184 causes arm 208 to rotate to a greater degree than arm 200. In fact, the multiple arm structure of the present invention causes spreader shaft 186 and spreader 180 to be lifted higher than it would be by a single arm extending between shaft 198 and spreader shaft 186.
As the spreader reaches the top of its motion, guide 190 is caused to rotate slightly in the direction of arrow 220, thus inducing a curve into the throw of the spreader 180 near its upper travel limit, as illustrated by arrow 194.
The replacement of the single arm with the two shorter arms 200 and 208 increases the throw of spreader 180. However, the lower travel limit of spreader 180 cannot be altered because spreader fork 182 must still meet the looper in the same position since the looper has not been moved. Although several methods of adjusting the lower travel limit of spreader 180 are available, in a preferred embodiment, the relative positioning and lengths of arms 200 and 208 were selected such that the increase in throw produced translated into an increase in both the upper and lower travel limit of the spreader shaft 186. Then, spreader shaft 186 was lengthened so that, overall, the lower travel limit of spreader 180 was returned to the original point even though the lower limit of spreader shaft 186 was lowered.
FIGS. 9A and 9B illustrate improvements made to the edging knife assembly of the Pegasus sewing machine in order to accommodate other improvements made to the machine. The Pegasus sewing machine comprises a knife assembly for cutting the material and creating the edge around which the overcast stitch is made. This assembly comprises a lower knife 250 fixedly attached to the lower housing 54. An upper knife 252 is mounted on a knife drive shaft 256 via a knife holder 258 and an arm 260. The knife drive shaft 256 reciprocates causing the upper knife 252 to meet with the lower knife 250 during the lower portion of its travel, similarly to a pair of scissors, and to rise above the lower knife during the upper portion of its travel.
The lengthened spreader shaft discussed above with respect to FIGS. 8A and 8B, however, interfered with knife arm 260. In order to provide the necessary clearance between knife arm 260 and the spreader shaft, the knife arm 260 was loosened from shaft 256, rotated upwardly (counterclockwise in FIG. 9B) and then reattached to shaft 256. However, after this modification, the upper knife 252 was too high and would no longer properly mate with the lower knife during the lower portion of its travel. Accordingly, a spacer 262 was added between the end of the arm 260 and the knife holder 258. The spacer 262 is shaped to lower the knife relative to the arm and move it slightly rearwardly (towards the right in FIG. 9B) by the thickness, t, of the spacer.
In the original Pegasus sewing machine, the knife holder 258 is screwed into a hole 266 in the end of arm 260 by screw 264, passing through hole 267 in the spacer 262. With the addition of the knife spacer 262, the spacer 262 is now screwed into the threaded hole 266 in the knife arm by screw 264 and the knife holder 258 is screwed into a second threaded hole 268 in the spacer by screw 265 as shown in FIG. 9B.
In order to accommodate the rearward displacement of the upper knife 252, the lower knife holder was also replaced with the knife holder 300 which moved the lower knife rearwardly by the same displacement as the upper knife.
Having thus described a few particular embodiments of the invention, various alterations, modifications and improvements will readily occur to those skilled in the art. Such alterations, modifications and improvements as are made obvious by this disclosure are intended to be part of this description though not expressly stated herein, and are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description is by way of example only, and not limiting. The invention is limited only as defined in the following claims and equivalents thereto. | The invention comprises improvements to sewing machines for increasing the throat clearance of the machine. The improvements relate to 1) modifications to mechanical components of the machine to increase the throw and upper travel limits of the presser foot, upper feeding foot, needle and spreader, 2) an adjustment for allowing the speed of the upper walking foot to be variable relative to the speed of the lower walking foot, and 3) an improved biasing spring for biasing the presser foot downward. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation-in-part application under 37 C.F.R. §1.63 of application Ser. No. 10/369,148 filed Feb. 19, 2003, currently pending; which is a continuation application of application Ser. No. 10/114,579, filed Apr. 2, 2002, now. U.S. Pat. No. 6,525,230; which is a continuation-in-part application of application Ser. No. 09/951,570 filed Sep. 11, 2001, now U.S. Pat. No. 6,462,243, claiming priority based on provisional application Ser. No. 60/284,642 filed Apr. 18, 2001.
TECHNICAL FIELD
[0002] This invention relates to zone reactors, and more particularly to zone reactors that are useful in processes for converting alkanes to alcohols, ethers, olefins, and other hydrocarbons.
BACKGROUND AND SUMMARY OF THE INVENTION
[0003] U.S. Pat. No. 6,462,243 discloses a method of converting alkanes to their corresponding alcohols and ethers using bromine. The patent comprises four embodiments of the invention therein disclosed each including a reactor wherein bromine reacts with an alkane to form alkyl bromide and hydrogen bromide, a converter wherein the alkyl bromide formed in the reactor reacts with metal oxide to form the corresponding alcohol or ether, and numerous other individual components.
[0004] The present invention comprises zone reactors wherein the several reactions disclosed in the co-pending parent application are carried out in a single vessel. In this manner the overall complexity of the system for converting alkanes to their corresponding alcohols, ethers, olefins, and other hydrocarbons is substantially reduced. In addition, heat generated by reactions occurring in particular zones within the vessel can be utilized to facilitate reactions occurring in other zones.
[0005] Various embodiments of the invention are disclosed. In accordance with a first embodiment the zone reactor comprises a countercurrent system wherein gases flow in a first direction and metal compounds flow in the opposite direction. A second embodiment of the invention comprises a cocurrent arrangement wherein the gases and the metal compounds travel in the same direction. The first and second embodiments of the invention are continuous systems as opposed to the third embodiment of the invention which is a fixed-bed system that is continual in operation. In accordance with the third embodiment the metal compounds remain fixed within the vessel while the gases are directed through the vessel first in one direction and later in the opposite direction.
[0006] In the following Detailed Description the invention is described in conjunction with the conversion of methane to methanol. However, as will be appreciated by those skilled in the art, the invention is equally applicable to the conversion of ethane and the higher alkanes to their corresponding alcohols, ethers, olefins, and other hydrocarbons.
[0007] The following Detailed Description also describes the invention in conjunction with the use of a particular halide, i.e., bromine. However, as will be appreciated by those skilled in the art, the invention is equally applicable to the conversion of alkanes to their corresponding alcohols, ethers, and other hydrocarbons utilizing other halides, including in particular chlorine and iodine.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] A more complete understanding of the present invention may be had by reference to the following Detailed Description when taken in connection with the accompanying Drawings wherein:
[0009] [0009]FIG. 1 is a diagrammatic illustration of a countercurrent zone reactor comprising a first embodiment of the invention;
[0010] [0010]FIG. 1A is an illustration of a variation of the countercurrent zone reactor of FIG. 1;
[0011] [0011]FIG. 2 is a diagrammatic illustration of a cocurrent zone reactor comprising a second embodiment of the invention;
[0012] [0012]FIG. 2A is an illustration of a variation of the cocurrent zone reactor of FIG. 2;
[0013] [0013]FIG. 3 is a diagrammatic illustration of a fixed bed zone reactor comprising a third embodiment of the invention;
[0014] [0014]FIG. 3A is an illustration of a variation of the fixed bed zone reactor of FIG. 3;
[0015] [0015]FIG. 14 is a diagrammatic illustration of a zone reactor comprising a fourth embodiment of the invention;
[0016] [0016]FIG. 4A is a sectional view of an apparatus useful in the practice of the embodiment of the invention shown in FIG. 3;
[0017] [0017]FIG. 4B is an illustration of an early stage in the operation of the apparatus of FIG. 4A;
[0018] [0018]FIG. 4C is an illustration of a later stage in the operation of the apparatus of FIG. 4A;
[0019] [0019]FIG. 4D is an illustration of a still later stage in the operation of the apparatus of FIG. 4A;
[0020] [0020]FIG. 5 is a diagrammatic illustration of the use of the apparatus of FIG. 4A in the conversion of mixtures of alkanes to chemically related products;
[0021] [0021]FIG. 6A is a sectional view diagrammatically illustrating an apparatus useful in practicing a variation of the embodiment of the invention illustrated in FIG. 3;
[0022] [0022]FIG. 6B is a diagrammatic illustration of the utilization of the apparatus of FIG. 6A;
[0023] [0023]FIG. 7 is a diagrammatic illustration of an apparatus useful in the practice of a variation of the embodiment invention shown in FIG. 3;
[0024] [0024]FIG. 8 is a sectional view taken along the line 8 - 8 in FIG. 7 in the direction of the arrows;
[0025] [0025]FIG. 9 is a diagrammatic illustration of a component part of the apparatus of FIG. 7;
[0026] [0026]FIG. 10 is a diagrammatic illustration of an apparatus useful in the implementation of a variation of the embodiment of the invention illustrated in FIG. 3;
[0027] [0027]FIG. 11 is the diagrammatic illustration of an apparatus useful in the practice of a fifth embodiment of the invention;
[0028] [0028]FIG. 12A is an illustration of a first step in the operation of the apparatus of FIG. 11;
[0029] [0029]FIG. 12B is an illustration of a later step in the operation of the apparatus of FIG. 11;
[0030] [0030]FIG. 13A is a diagrammatic illustration of a first step in the operation of an apparatus comprising a variation of the apparatus illustrated in FIG. 11;
[0031] [0031]FIG. 13B is an illustration of a later step in the operation of the apparatus of FIG. 13A;
[0032] [0032]FIG. 15A is a diagrammatic illustration of a first step in the operation of an apparatus comprising a variation of the apparatus illustrated in FIG. 11; and
[0033] [0033]FIG. 15B is an illustration of a later step in the operation of the apparatus of FIG. 15A.
DETAILED DESCRIPTION OF THE INVENTION
[0034] The present invention comprises zone reactors wherein three sequential chemical reactions occur in separate zones within a single vessel. In Zone 1 oxygen is reacted with a metal bromide to form bromine gas and the corresponding metal oxide. Bromine gas from Zone 1 passes to Zone 2 where the second chemical reaction occurs. In Zone 2 methane gas is introduced at an intermediate point in the vessel. Methane reacts with the bromine from Zone 1 to form methyl bromide and hydrogen bromide. The latter gasses pass into Zone 3 where the third chemical reaction causes methyl bromide and hydrogen bromide to react with metal oxide to form methanol and metal bromide. Methanol is converted to the liquid phase by condensation and is recovered from the reactor vessel as a liquid. Excess gasses, mostly methane, are separated from the recovered methanol and are returned to the zone reactor along with fresh methane. Metal oxide from Zone 1 is transported to Zone 3 where it proceeds from Zone 3 through Zone 2 to Zone 1 thereby completing the cycle.
[0035] Reactions in Zone 1 are endothermic; therefore, means to supply heat are provided. Zone 2 and Zone 3 involve exothermic reactions; therefore, means to remove heat are provided.
[0036] The separation of zones is not necessarily a sharp one since there is no physical barrier between zones. Therefore, some overlap of reactions may occur. The important element, however, is that all the oxygen is converted to metal oxide in Zone 1 so that little or no oxygen remains to react with methane in Zone 2 . In Zone 2 other bromides, i.e., higher brominated species, in addition to methyl bromide may form and result in products other than methanol in Zone 3 , such as various ethers. Any by-products are separated from methanol in various isolation/purification steps. Any unreacted methane in Zone 2 will pass through Zone 3 and be recycled in Zone 2 . Other unreacted brominated species are returned to Zone 2 either for reaction or to suppress further formation of the higher brominated species by satisfying chemical equilibrium.
[0037] The zone reactor operates at essentially atmospheric pressure and at temperatures up to about 750F. The principal advantage over conventional methanol process lies in the simplicity of the system. The zone reactor achieves the synthesis of methanol in a single vessel whereas the conventional process requires multiple vessels to first produce synthesis gas followed by catalytic reaction. Furthermore the zone reactor operates at slightly above atmospheric pressure whereas the conventional process requires pressures up to 200 atmospheres.
[0038] As will be appreciated by those skilled in the art, the zone reactors of the present invention can be used with ethane and higher alkanes to produce corresponding alcohols, ethers, olefins, and other hydrocarbons.
[0039] The zone reactor also has advantages over a multi-step process utilizing the same bromine chemistry. One advantage is that one step replaces several. In addition, bromine gas remains in one vessel and need not be condensed and re-vaporized.
[0040] [0040]FIG. 1 shows a countercurrent system employing the zone reactor of the present invention. In this embodiment gasses flow upward through a bed of solids which is moving downward. Oxygen is introduced at the bottom of the vessel and reacts with a metal bromide to form bromine gas and the corresponding metal oxide. This step entails regeneration of the metal oxide, which was expended in Zone 3 . Bromine from Zone 1 proceeds to Zone 2 where methane gas is introduced. The methane reacts with the bromine to form methyl bromide and hydrogen bromide. The latter two gasses proceed upward to Zone 3 where fresh metal oxide reacts with these gasses to form methanol and metal bromide. The regenerated metal oxide from Zone 1 is returned to Zone 3 thereby completing the cycle.
[0041] The reaction in Zone 1 may require heat. If so, a suitable heat supply apparatus is provided. In Zone 2 the reactions are exothermic. Heat from the Zone 2 reactor is allowed to raise the temperature of the gasses formed. Zone 3 involves reactions that may require the removal of heat; therefore, a suitable heat removal apparatus is provided.
[0042] The zone reactor of FIG. 1 comprises a unitary vessel. Referring to FIG. 1A, the zone reactor of FIG. 1 may also comprise a vessel having multiple components which are secured one to another by suitable fasteners. This allows removal of components of the vessel for cleaning and/or repair.
[0043] [0043]FIG. 2 shows a cocurrent system employing the zone reactor concept. In this system gasses and solids proceed together in the same direction. In addition the solids are suspended in the gas flow in a way such that the gasses transport the solids. This embodiment combines the reaction steps with the physical movement of the solids. The chemical reaction steps are as described for FIG. 1.
[0044] The zone reactor of FIG. 2 comprises a unitary vessel. Referring to FIG. 2A, the zone reactor of FIG. 2 may also comprise a vessel having multiple components which are secured one to another by suitable fasteners. This allows removal of components of the vessel for cleaning and/or repair.
[0045] [0045]FIG. 3 shows a fixed-bed system comprising a third embodiment of the invention. Whereas FIGS. 1 and 2 describe continuous systems, FIG. 3 describes a continual system. In the system of FIG. 3 the metal bromide/oxide solids remain fixed within the vessel while gasses are passed through the vessel. The regeneration step is carried out in place by reversing the flow of gases through the system. The steps involved and the order in which they are performed are described in FIG. 3. This mode of operation distinguishes itself by avoiding movement of solids as in the embodiments of FIGS. 1 and 2. In addition, by carefully setting the duration of each step the heat generated in Zones 2 and 3 can be at least partially allowed to raise the temperature of the bed. Then, when flow is reversed and Zone 3 becomes Zone 1 , the heat stored in the solids can be used to provide the reaction heat needed in Zone 1 . In this way the overall effect is a direct transfer of heat from the exothermic zone to the zone where it is needed without going through an intermediate step such as steam generation. However, since the heat generated in Zones 2 and 3 is likely to be greater than that needed in Zone 1 , it may still be necessary to remove some heat from the system.
[0046] The zone reactor of FIG. 3 comprises a unitary vessel. Referring to FIG. 3A, the zone reactor of FIG. 3 may also comprise a vessel having multiple components which are secured one to another by suitable fasteners. This allows removal of components of the vessel for cleaning and/or repair.
[0047] Referring to FIG. 14, the zone reactor of the present invention may also comprise separate vessels. Utilization of separate vessels to define the zone reactor allows the use of pumps to control the pressure at which the reaction within each individual vessel takes place. Utilization of separate vessels also allows the use of valves to prevent outflow from a particular vessel until the reaction therein has been completed and to thereafter facilitate transfer of the action products to the next zone.
[0048] The physical separation of the chemical species formed during operation of the zone reactors disclosed herein is accomplished by conventional means, with valuable products and by-products recovered and other useful species returned to the appropriate zone for conversion or satisfaction of chemical equilibrium.
[0049] Referring to FIG. 4A an apparatus 20 is diagrammatically illustrated. The apparatus 20 comprises an imperforate cylinder 22 formed from an appropriate metal, an appropriate polymeric material, or both. The cylinder 22 has closed ends 24 and 26 . A passageway 28 extends through the end 24 of the cylinder 22 , a passageway 30 extends through the end 26 of the cylinder 22 , and a passageway 32 extends to the central portion of the cylinder 22 between the ends 24 and 26 thereof.
[0050] The apparatus 20 further comprises a first zone 34 which is initially filled with metal halide. A second zone 36 located at the opposite end of the cylinder 22 from zone 34 is initially filled with metal oxide. A third or central zone 38 which is centrally disposed between the first zone 34 and the second zone 36 is initially empty.
[0051] Referring to FIG. 4B, a first stage in the operation of the apparatus 20 is shown. Oxygen or air is directed into the first zone 34 through the opening 28 . The oxygen or the oxygen from the air reacts with the metal halide to produce metal oxide and halide. The halide flows from the first zone 34 into the central zone 38 .
[0052] Simultaneously with the introduction of oxygen or air into the first zone 34 through the opening 28 , a selected alkane is directed into the central zone 38 through the opening 32 . Within the central zone 38 halide reacts with alkane to produce alkyl halide and hydrogen halide. The alkyl halide and the hydrogen halide pass from the central zone 38 to the second zone 36 .
[0053] Within the second zone 36 the alkyl halide and the hydrogen halide react with metal oxide to produce products which are recovered through the passageway 30 . The reaction within the second zone 36 also produces metal halide.
[0054] Referring to FIG. 4C, the foregoing reactions in the first zone 34 , the central zone 38 , and the second zone 36 continue until substantially all of the metal halide that was originally in the first zone 34 has been converted to metal oxide. Simultaneously, substantially all of the metal oxide that was originally in the second zone 36 is converted to metal halide. At this point the reaction is stopped and the central zone 38 is evacuated.
[0055] The next stage in the operation of the apparatus 20 is illustrated in FIG. 4D. The reactions described above in conjunction in conjunction with FIG. 4B are now reversed, with oxygen or air being admitted to the second zone 36 through the opening 30 . The oxygen or oxygen from the air reacts with the metal halide in the second zone 36 to produce halide and metal oxide. The halide from the reaction in the second zone 36 passes to the central zone 38 where it reacts with alkane received through the opening 32 to produce alkyl halide and hydrogen halide. Alkyl halide and hydrogen halide from the reaction within the central zone passed to the first zone 34 where they react with the metal oxide contained therein to produce product and metal halide. The reactions continue until substantially all of the metal halide in the second zone has been converted to metal oxide and substantially all of the metal oxide within the first zone 34 has been converted to metal halide at which time the apparatus 20 is returned to the configuration of FIG. 4A. At this point the central zone 38 is evacuated and the above described cycle of operation is repeated.
[0056] Referring to FIG. 5 there is shown an apparatus 40 useful in the practice of the third embodiment of the invention as illustrated in FIG. 3 and described hereinabove in conjunction therewith. Many of the component parts of the apparatus 40 are identical in construction and function to component parts of the apparatus 20 illustrated in FIGS. 4A-4B, inclusive, and described hereinabove in conjunction therewith. Such identical component parts are designated in FIG. 5 with the same reference numerals utilized in the foregoing description of the apparatus 20 .
[0057] The apparatus 40 comprises first and second cylinders 42 and 44 . The cylinders 42 and 44 are each identical in construction and function to the cylinder 22 illustrated in FIGS. 4A-4D, inclusive, and described above in conjunction therewith. The cylinder 42 receives a mixture of alkanes, including methane, ethane, propane, etc., through the opening 32 thereof. The several reactions that occur within the cylinder 42 produce products and methane which are initially recovered through the opening 30 .
[0058] The methane resulting from the reactions which occur within the cylinder 42 is separated from the products resulting from the reactions within the cylinder 42 by conventional techniques such as distillation. The methane is then directed into the cylinder 44 through the opening 32 thereof. Within the cylinder 44 the methane is converted to products utilizing the same reactions described above in conjunction with the apparatus 20 . Products resulting from the reactions occurring within the cylinder 44 are initially recovered through the opening 30 thereof.
[0059] As will be understood by reference to the foregoing description of the operation of the apparatus 20 , operation of the apparatus 40 continues until substantially all of the metal halide that was originally in the first zones 34 of the cylinders 42 and 44 has been converted to metal oxide and until substantially all of the metal oxide that was originally in the second zones 36 of the cylinders 42 and 44 has been converted to metal halide. At this point the direction of flow through the cylinders 42 and 44 is reversed. That is, oxygen is directed into the cylinders 42 and 44 through the passageways 30 , products and methane are recovered from the cylinder 42 through the passageway 28 , and products are recovered from the cylinder 44 through the passageway 28 .
[0060] Referring to FIG. 6A, there is shown an apparatus 50 useful in the practice of a variation of the third embodiment of the invention as illustrated in FIG. 3 and described hereinabove in conjunction therewith. Many of the component parts of the apparatus 50 are substantially identical in construction and function to component parts of the apparatus 20 illustrated in FIGS. 4A-4D, inclusive, and described hereinabove in conjunction therewith. Such substantially identical component parts are designated in FIGS. 6A and 6B with the same reference numerals utilized above in the description of the apparatus 20 but are differentiated there from by means of a prime (′) designation.
[0061] The apparatus 50 differs from the apparatus 20 of FIGS. 4A-4D, inclusive, in that the cylinder 22 ′ of the apparatus 50 includes additional zones 52 and 54 therein. Each of the zones 52 and 54 receives a catalyst the function of which is to facilitate coupling of the alkyl halide molecules produced by the reaction occurring within the central zone 38 ′ thereby producing products comprising higher numbers of carbon atoms than would otherwise be the case. Preferably the catalyst that is contained within the zones 52 and 54 is a selected zeolite. However, the catalyst received within the zones 52 and 54 may also comprise a metal halide/oxide. If a metal halide/oxide is employed within the zones 52 and 54 , it preferably comprises a different metal halide/oxide as compared with the metal halide/oxide that is utilized in the zones 34 and 36 . Operation of the apparatus 50 proceeds identically to the operation of the apparatus 20 as described above except that the presence of a catalyst in the zones 52 and 54 facilitates coupling of the alkyl halide molecules produced within the zone 38 to products.
[0062] Referring now to FIGS. 7, 8, and 9 , there is shown an apparatus 60 useful in the practice of the third embodiment of the invention as illustrated in FIGS. 3 and described hereinabove in conjunction therewith. The construction and operation of the apparatus 60 is similar in many respects to the construction and operation of the apparatus 50 as shown in FIGS. 6A and 6B and described hereinabove in conjunction therewith.
[0063] The apparatus 60 comprises a barrel 62 having a plurality of cylinders 64 mounted therein. The cylinders 64 are imperforate except that each cylinder 64 has a central portion 66 which is perforated. Alkane is received in the barrel 62 through an inlet 68 and passes from the barrel 62 into the cylinders 64 through the perforations comprising the portions 66 thereof. The pressures of the alkane within the barrel 62 is maintained high enough such that alkane flows into the cylinders 64 while preventing the outflow of reaction products therefrom.
[0064] The cylinders 64 of the apparatus 60 are further illustrated in FIG. 9. As indicated above, each cylinder 64 is imperforate except for the perforated portion 66 thereof. The cylinder 64 has end walls 68 and 70 situated at the opposite ends thereof. Each of the end walls 68 and 70 is provided with an oxygen or air receiving passageway 72 and a product discharge passageway 74 .
[0065] Each cylinder 64 comprises a first zone 76 which initially contains metal halide and a second zone 78 which initially contains metal oxide. A third or central zone 80 receives halide through the perforations comprising the perforated portion 66 of the cylinder 64 . Zones 82 located between the zones 76 and 78 , respectively, and the zone 80 contain a catalyst.
[0066] The catalyst contained within the zone 82 preferably comprises a selected zeolite. The catalyst may also comprise a metal halide/oxide. If employed, the metal halide/oxide of the zones 82 is preferably a different metal halide/oxide as compared with the metal halide/oxide comprising the zones 76 and 78 .
[0067] Operation of the apparatus 60 is substantially identical to the operation of the apparatus 50 as illustrated in FIGS. 6A and 6B and described hereinabove in conjunction therewith. Oxygen or air is initially directed into the cylinder 64 through the passageway 72 . The oxygen or the oxygen from the air reacts with the metal halide within the zone 76 to produce halide and metal oxide. The halide passes into the central zone 80 where it reacts with the alkane therein to produce alkyl halide and hydrogen halide. The alkyl halide and hydrogen halide pass through the catalyst within the zone 82 which facilitates coupling of the molecules comprising the alkyl halide into molecules having larger numbers of carbon atoms. The hydrogen halide and the now-coupled alkyl halide next pass into the zone 78 where the hydrogen halide and coupled alkyl halide react with the metal oxide therein to produce product and water. The product and the water are recovered from the cylinder 64 through the outlet 74 .
[0068] The foregoing process continues until substantially all of the metal halide within the zone 76 is converted to metal oxide and substantially all of the metal oxide in the zone 78 is converted to metal halide. At this point the direction of flow through the cylinder 64 is reversed with oxygen or air being received through the opening 72 in the end 70 of the cylinder 64 and products and water being recovered through the opening 74 formed in the end 68 of the cylinder 64 .
[0069] Referring to FIG. 10, there is shown an apparatus 90 useful in the practice of the third embodiment of the invention as illustrated in FIG. 3 and described hereinabove in conjunction therewith. The apparatus 90 comprises the barrel 92 having a heat transfer fluid 94 contained therein. The barrel 92 further comprises a bromination manifold 96 situated at one end thereof and a pair of oxygen receiving/product discharge manifolds 98 and 100 situated at the opposite end thereof.
[0070] A baffle 102 is centrally disposed within the barrel 92 . A plurality of tubular passageways 104 are situated on one side of the baffle 102 and extend between the oxygen receiving/product discharge manifold 98 and the bromination manifold 96 . A plurality of tubular passageways 106 extend between the manifold 96 and the manifold 100 .
[0071] The tubes 104 are initially packed with metal halide. Oxygen or air is received in the manifold 98 through a passageway 108 . The oxygen or the oxygen from the air react with the metal halide within the tubes 104 to produce halide and metal oxide. Halide flows from the tubes 104 into the manifold 96 where it reacts with alkane which is received in the manifold 96 through a passageway 110 .
[0072] The reaction of the halide with the alkane within the manifold 96 produces alkyl halide and hydrogen halide. The tubes 106 are initially filled with metal oxide. The alkyl halide and the hydrogen halide resulting from the reaction within the manifold 96 pass through the tubes 106 thereby converting the metal oxide contained therein to metal halide and producing products. The products are received in the manifold 100 and are recovered there from through a passageway 112 .
[0073] As indicated above, the reaction between the oxygen or the oxygen from the air and the metal halide may be endothermic. Conversely, the reaction of the alkyl halide and the hydrogen halide with the metal oxide may be exothermic. It is also possible that, under certain circumstances, the oxidation of the metal halide is an exothermic reaction and/or that the halide/metal oxide reaction is endothermic. The heat transfer fluid 94 within the barrel 92 flows around the baffle 102 as indicated by the arrows 114 thereby transferring heat between the exothermic reaction and the endothermic reaction and in this manner each achieves thermodynamic equilibrium.
[0074] The reaction of the oxygen or the oxygen from the air with the metal halide within the tubes 104 continues until substantially all of the metal halide has been converted to metal oxide. Similarly, the reaction of the alkyl halide and the hydrogen halide with the metal oxide within the tubes 106 continues until substantially all of the metal oxide has been converted to metal halide. At this point the direction of flow through the apparatus 90 is reversed with oxygen or air being received through the passageway 112 and products being recovered through the passageway 108 .
[0075] Referring to FIGS. 11, 12A, and 12 B, there is shown an apparatus 120 which is useful in the practice in the third embodiment of the invention as illustrated in FIG. 3 and described hereinabove in conjunction therewith. The apparatus 20 includes a bromination chamber 122 which is divided into first and second portions 124 and 126 by a piston 128 . A valve 130 selectively controls the flow of oxygen or air received through a passageway 132 into the portion 124 of the chamber, or directs the flow of products outwardly from the apparatus 120 through a passageway 134 . Oxygen or air entering the apparatus 120 through the passageway 132 and the valve 130 passes through a passageway 136 into a chamber 138 which initially contains metal halide. Within the chamber 138 the oxygen or the oxygen from the air reacts with the metal halide to produce halide and metal oxide. Halide passes from the chamber 138 through a passageway 140 into the portion 124 of the chamber 122 .
[0076] Alkane is received in the portion 124 of the chamber 122 through a passageway 142 , a valve 144 , and a passageway 146 . Within the portion 124 the alkane reacts with halide produced by the reaction within the chamber 138 to produce alkyl halide and hydrogen halide. As the reaction continues the alkyl halide and the hydrogen halide force the piston 128 to move rightwardly (FIG. 11). This process continues until all of the metal halide within the chamber 138 has been converted to metal oxide and the piston 128 has been forced to the extreme right hand end (FIG. 11) of the chamber 122 .
[0077] At the beginning of the procedure just described the portion 126 of the chamber 122 was filled with alkyl halide and hydrogen halide. As will be appreciated by those skilled in the art, the presence of alkyl halide and hydrogen halide in the portion 126 resulted from a flow of oxygen or air through a passageway 148 , a valve 150 , and a passageway 152 into a chamber 154 which was initially filled with metal halide. Reaction of the oxygen or the oxygen from the air with the metal halide produced halide and metal oxide. The halide flowed through a passageway 156 into the portion 126 of the chamber 122 where the halide reacted with alkane received through the passageway 142 , and valve 158 , and a passageway 160 . Within the portion 126 of the chamber 122 the halide reacted with the alkane to produce alkyl halide and hydrogen halide. The production of alkyl halide and hydrogen halide within the portion 126 of the chamber 122 continued until substantially the entire content of the chamber 154 was converted from metal halide to metal oxide.
[0078] Referring particularly to FIG. 12A, rightward movement of the piston 128 forces the alkyl halide and the hydrogen halide outwardly from the portion 126 of the chamber 122 through the passageway 156 into the chamber 154 . At this point the chamber 154 is filled with metal oxide. The alkyl halide and the hydrogen halide from the portion 126 of the chamber 122 react with the metal oxide in the chamber 154 to produce product and water. The product and water pass through the passageway 152 , the valve 150 , and a passageway 162 and are recovered.
[0079] When the piston 128 has reached the right hand end of the chamber 122 , substantially all of the alkyl halide and hydrogen halide have been forced out of the portion 126 of the chamber 122 and have been converted to product by reaction with metal oxide within the chamber 154 . At this point substantially all of the metal oxide within the chamber 154 has been converted back to metal halide. The positioning of the valve 150 is reversed thereby admitting oxygen or air into the chamber 154 through the passageway 148 , the valve 150 , and the passageway 152 . Meanwhile, the positioning of the valve 130 is likewise reversed thereby facilitating the recovery of product resulting from the reaction of the alkyl halide and the hydrogen halide within the portion 124 of the chamber 122 with the metal oxide within the chamber 138 . Thus, the process is continuous with the piston 128 moving back and forth within the chamber 122 to force previously produced alkyl halide and hydrogen halide outwardly through the metal oxide contained in the associated chamber 138 or 154 to produce product.
[0080] Referring to FIGS. 13A and 13B, there is shown an apparatus 170 . All of the component parts of the apparatus 170 are identical to components of the apparatus 120 as illustrated in FIGS. 11, 12A, and 12 B and described hereinabove in conjunction therewith. Such duplicate component parts are identified in FIGS. 13A and 13B with the same reference numerals utilized above in the description of the apparatus 120 .
[0081] The apparatus 170 employs duplicate chambers 138 and 154 along with duplicate components controlling the flow of materials to and from the chambers 138 and 154 . The use of duplicate chambers 138 and 154 and duplicate components ancillary thereto is useful in increasing the throughput rate of the apparatus 170 as compared with that of the apparatus 120 and/or in balancing the kinetics of the reactions occurring within the chambers 138 and 154 .
[0082] Referring to FIGS. 15A and 15B, there is shown an apparatus 172 . All of the component parts of the apparatus 172 are identical to components of the apparatus 120 as illustrated in FIGS. 11, 12A, and 12 B and described hereinabove in conjunction therewith. Such duplicate component parts are identified in FIGS. 15A and 15B with the same reference numerals utilized above in the description of the apparatus 120 .
[0083] The apparatus 172 employs duplicate chambers 122 along with duplicate components controlling the flow of materials to and from the chambers 122 . The use of duplicate chambers 122 and duplicate components ancillary thereto is useful in increasing the throughput rate of the apparatus 170 as compared with that of the apparatus 120 and/or in balancing the kinetics of the reactions occurring within the chambers 122 .
[0084] Although preferred embodiments of the invention have been illustrated in the accompanying Drawing and described in the foregoing Detailed Description, it will be understood that the invention is not limited to the embodiments disclosed but is capable of numerous rearrangements, modifications, and substitutions of parts and elements without departing from the spirit of the invention. | In a method of converting alkanes to their corresponding alcohols, ethers, olefins, and other hydrocarbons, a vessel comprises a hollow, unsegregated interior defined first, second, and third zones. In a first embodiment of the invention oxygen reacts with metal halide in the first zone to provide gaseous halide; halide reacts with the alkane in the second zone to form alkyl halide; and the alkyl halide reacts with metal oxide in the third zone to form a hydrocarbon corresponding to the original alkane. Metal halide from the third zone is transported through the vessel to the first zone and metal oxide from the first zone is recycled to the third zone. A second embodiment of the invention differs from the first embodiment in that metal oxide is transported through the vessel from the first zone to the third zone and metal halide is recycled from the third zone to the first zone. In a third embodiment of the invention the flow of gases through the vessel is reversed to convert the metal oxide back to metal halide and to convert the metal halide back to the metal oxide. | 8 |
[0001] The present application claims the priority of Chinese Patent Application Ser. No. 201510382555.1 filed on Jul. 3, 2015, and entitled “Graphene/Porous Iron Oxide Nanorod Composite and Method for Preparing the same”, the entire contents of which are hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to the technical field of material chemistry, and more particularly, to a graphene/porous iron oxide nanorod composite and a method for preparing the same.
DESCRIPTION OF THE RELATED ART
[0003] As a primary source of energy of portable devices, lithium batteries are being expanded continuously in application fields, including electronic engines and green energy and the like. Although some advances have been made commercially in lithium batteries, their use is limited in a wide range of application due to the disadvantages such as low energy storage and poor cycling stability . Therefore, currently, many researches focus on finding an efficient lithium battery electrode material, for example, a low dimensional metal oxide material. Among alternative negative electrode materials, Fe 2 O 3 , as one of transition metal oxides, has attracted increasing attention, because its theoretical capacity (1007 mAh g −1 ) is much higher than that of graphite and other transition metal oxides (such as SnO 2 ) and it is inexpensive, abundant and environmentally friendly.
[0004] However, Fe 2 O 3 materials have poor conductivity and exhibit a large volume expansion during charge and discharge, this hinders their practical applications in lithium batteries. The way to overcome this problem is to seek an active material having a high specific surface area and a short diffusion path for compounding with it. A large specific surface area enables metal oxides to have more lithium storage sites and larger electrode-electrolyte contact area for easy diffusion of lithium ions. Therefore, due to huge specific surface area and good conductivity, graphene is an ideal alternative material .
[0005] In addition, numerous studies show that fibroin can regulate the nano-structures, hydrophilicity and hydrophobicity of nanomaterials by controlling the self-assembly, thereby providing a controllable template for synthesizing copper oxide, silver and other inorganic nanoparticles. Synthesis of the materials such as α-Fe 2 O 3 /graphene, α-Fe 2 O 3 /CNTs, α-Fe 2 O 3 /carbon has been reported, but synthesis of a porous Fe 2 O 3 nanorod/graphene composite regulated by fibroin has not been reported.
SUMMARY OF THE INVENTION
[0006] In order to solve the technical problems above, an object of the present invention is to provide a graphene/porous iron oxide nanorod composite and preparation method thereof. The raw materials used in synthesis are inexpensive and readily available, and the synthesis method is simple.
[0007] In one aspect, the present invention discloses a graphene/porous iron oxide nanorod composite, including graphene and Fe 2 O 3 nanoparticles loaded on the graphene, the Fe 2 O 3 nanoparticles have a honeycomb porous structure.
[0008] Preferably, the Fe 2 O 3 nanoparticles have a rod-shaped morphology.
[0009] In another aspect, the present invention also discloses a method for preparing a graphene/porous iron oxide nanorod composite, the method comprises the steps of:
[0010] (1) mixing graphene oxide with a fibroin solution, and adding hydrazine hydrate for reduction after pH is adjusted to alkaline, to obtain a graphene/fibroin composite;
[0011] (2) adding an iron source to the graphene/fibroin composite, and further stirring until complete dissolution to get a mixture;
[0012] (3) pouring the mixture into a reactor and performing a reaction at 120-200° C. for 8-36 h;
[0013] (4) naturally cooling to room temperature after the end of the reaction, centrifuging and drying the product, to obtain a solid powder; and
[0014] (5) calcinating the solid powder in an inert atmosphere at 320-450° C. for 3-8 h, and naturally cooling to room temperature, to get the nanorod composite.
[0015] Preferably, the weight ratio of the graphene oxide to fibroin is less than or equal to (not greater than) 1:4.
[0016] Preferably, the weight ratio of the graphene oxide to hydrazine hydrate is 1:(0.0004-20).
[0017] Preferably, the iron source is FeCl 3 .6H 2 O, and the weight ratio of the graphene oxide to FeCl 3 .6H 2 O is 1:(20-60).
[0018] Preferably, in the step (1) the pH is 8-11.
[0019] By means of the above technical solutions, the present invention has the following advantages: in the present invention, iron oxide nanoparticles are compounded with graphene, graphene has a large specific surface area and a good conductivity, and enhances the discharge capacity of the iron oxide materials. The pore structure of iron oxide increases the specific surface area of iron oxide nanoparticles, such that they have more lithium storage sites and larger contact area. In the invention, fibroin induces iron oxide nanoparticles to form a rod-shaped structure and honeycomb holes, raw materials of the invention are inexpensive and readily available, has good biocompatibility and no contamination to the environment, and can be easily removed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The accompanying drawings are intended for further understanding of the invention as a part of the present application. The exemplary embodiments and description thereof of the invention are used for illustrating the present invention and are not intended to limit the invention in any way. In the drawings:
[0021] FIG. 1 is an SEM image of a sample in an embodiment 1 according to the present invention;
[0022] FIG. 2 is a TEM image of the sample in the embodiment 1 according to the present invention;
[0023] FIG. 3 is an XRD spectrum of the sample in the embodiment 1 according to the present invention;
[0024] FIG. 4 is a Raman spectrum of the sample in the embodiment 1 according to the present invention;
[0025] FIG. 5 is an SEM image of a sample in an embodiment 2 according to the present invention;
[0026] FIG. 6 is an SEM image of a sample in an embodiment 3 according to the present invention;
[0027] FIG. 7 is an SEM image of a sample in an embodiment 4 according to the present invention; and
[0028] FIG. 8 is an XRD spectrum of the sample in the embodiment 4 according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] The present invention will be explained in more detail below with reference to the drawings and in connection with embodiments.
Embodiment 1
[0030] A method for preparing a graphene/porous iron oxide nanorod composite, comprises the following steps:
[0031] (1) 0.05 g graphene oxide was mixed with 16 mL of fibroin solution of 5.06 wt %, pH was adjusted to 10, and 0.2 mL hydrazine hydrate was added to induce reduction, and a graphene-fibroin nanofiber composite was obtained;
[0032] (2) 2.15 g FeCl 3 .6H 2 O was added into the graphene-fibroin nanofiber composite, and stirring was continuously until complete dissolution to get a mixture;
[0033] (3) the mixture was poured into a reactor and reaction was carried out at 160° C. for 20 h;
[0034] (4) after completion of the reaction, the resulting mixture was naturally cooled to room temperature, and the product was centrifuged, washed, and finally dried in vacuum to obtain a solid powder; and
[0035] (5) the resultant solid powder was calcinated in a vacuum tubular furnace in an argon atmosphere at 400° C. for 5 h, and then was naturally cooled to room temperature to get the nanorod composite.
[0036] FIG. 1 to FIG. 4 are an SEM image, TEM image, XRD spectrum, and Raman spectrum of a sample in embodiment 1 of the present invention, respectively. It can be seen from FIG. 1 and FIG. 2 that, the sample prepared by the method appears a one dimensional rod-shaped structure. It can be seen from FIG. 2 that, the rod-shaped iron oxide nanoparticles have honeycomb holes thereon. FIG. 3 shows that the sample is iron oxide. FIG. 4 further shows that the product is a composite of iron oxide with graphene.
Embodiment 2
[0037] A method for preparing a graphene/porous iron oxide nanorod composite, comprises the following steps:
[0038] (1) 0.05 g graphene oxide was mixed with 0.19 mL of fibroin solution of 5.06 wt %, pH was adjusted to 10, and 1 mL hydrazine hydrate was added to induce reduction, and a graphene-fibroin nanofiber composite was obtained;
[0039] (2) 1 g FeCl 3 .6H 2 O was added into the graphene-fibroin nanofiber composite, and stirring was continuously until complete dissolution to get a mixture;
[0040] (3) the mixture was poured into a reactor and reaction was carried out at 120° C. for 36 h;
[0041] (4) after completion of the reaction, the resulting mixture was naturally cooled to room temperature, and the product was centrifuged, washed, and finally dried in vacuum to obtain a solid powder; and
[0042] (5) the resultant solid powder was calcinated in a vacuum tubular furnace in an argon atmosphere at 320° C. for 8 h, and then was naturally cooled to room temperature to get the nanorod composite.
[0043] FIG. 5 is an SEM image, and it can be seen from the FIG. 5 that, parts of the composite are rod-shaped, and parts of are irregular-shaped.
Embodiment 3
[0044] A method for preparing a graphene/porous iron oxide nanorod composite, comprises the following steps:
[0045] (1) 0.05 g graphene oxide was mixed with 10 mL of fibroin solution of 5.06 wt %, pH was adjusted to 10, and 20 uμL hydrazine hydrate was added to induce reduction, and a graphene-fibroin nanofiber composite was obtained;
[0046] (2) 3 g FeCl 3 .6H 2 O was added into the graphene-fibroin nanofiber composite, and stirring was continuously until complete dissolution to get a mixture;
[0047] (3) the mixture was poured into a reactor and reaction was carried out at 200° C. for 8 h;
[0048] (4) after completion of the reaction, the resulting mixture was naturally cooled to room temperature, and the product was centrifuged, washed, and finally dried in vacuum to obtain a solid powder; and
[0049] (5) the resultant solid powder was calcinated in a vacuum tubular furnace in an argon atmosphere at 450° C. for 3 h, and then was naturally cooled to room temperature to get the nanorod composite.
[0050] FIG. 6 is an SEM image of the sample, and it can be seen from the FIG. 6 that, the composite are rod-shaped.
Embodiment 4
[0051] A method for preparing a graphene/porous iron oxide nanorod composite, comprises the following steps:
[0052] The synthesis method in this embodiment 4 was similar to that in the embodiment 1, except that the step (5) was omitted.
[0053] FIG. 7 is an SEM image of a sample, and it can be seen from the FIG. 7 that, the composite also shows a rod-shaped structure before calcinating. FIG. 8 is an XRD spectrum of the sample, showing that the product before the composite is calcinated is FeOOH.
[0054] In conclusion, the present invention provides a method for preparing a graphene/porous iron oxide nanorod composite. The raw materials of the method are widely available, inexpensive, and the synthesis process is simple. In the present invention, iron oxide nanoparticles are compounded with graphene, graphene has a large specific surface area and a good conductivity, and enhances the discharge capacity of the iron oxide material. The pore structure of iron oxide increases the specific surface area of iron oxide nanoparticles, such that they have more lithium storage sites and larger contact area. In the invention, fibroin induces iron oxide nanoparticles to form a rod-shaped structure and a honeycomb structure, raw materials of the invention are inexpensive and readily available, has good biocompatibility and no contamination to the environment, and can be easily removed.
[0055] The above description is only preferred embodiments of the present invention and not intended to limit the present invention, it should be noted that those of ordinary skill in the art can further make various modifications and variations without departing from the technical principles of the present invention, and these modifications and variations also should be considered to be within the scope of protection of the present invention. | The present invention discloses a graphene/porous iron oxide nanorod composite and a method for preparing the same. The composite includes graphene and Fe 2 O 3 nanoparticles loaded on the graphene. The Fe 2 O 3 nanoparticles have a honeycomb porous structure. The synthesis method of the composite is simple and the raw materials are inexpensive. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application Ser. No. 12/495,356 filed on Jun. 30, 2009, the disclosure of which is incorporated herein in its entirety by reference.
TECHNICAL FIELD
[0002] The presently disclosed technologies are directed to an apparatus for and a method of registering the lateral position of a sheet in a media handling assembly, such as a printing system, using adjustable idler rollers.
BACKGROUND
[0003] In media handling assemblies, particularly in printing systems, accurate and reliable registration of the substrate media as it is transferred in a process direction is desirable. In particular, accurate registration of the substrate media, such as a sheet of paper, as it is delivered at a target time to an image transfer zone will improve the overall printing process. The substrate media is generally conveyed within the system in a process direction. However, often the substrate media can shift in a cross-process direction that is lateral to the process direction or even acquire an angular orientation, referred herein as “skew,” such that its opposed linear edges are no longer parallel to the process direction. Thus, there are three degrees of freedom in which the substrate media can move, which need to be controlled in order to achieve accurate delivery thereof. A slight lateral misalignment, skew or error in the arrival time of the substrate media through a critical processing phase can lead to errors, such as image and/or color registration errors. Also, as the substrate media is transferred between sections of the media handling assembly, the amount of positioning error can increase or accumulate.
[0004] Contemporary media handling systems attempt to achieve position registration of sheets by separately varying the speeds of spaced apart drive wheels to correct for skew and/or lateral mispositioning of the sheet. Such systems that separately vary the drive wheel speeds are commonly referred to as differential drive systems. The drive wheels are used with cooperating idler rollers for engaging the substrate media there between. The differential drive wheels with the idler rollers are together referred to as differential nip assemblies.
[0005] Examples of typical sheet registration and deskewing systems are disclosed in U.S. Pat. Nos. 5,094,442, 6,533,268, 6,575,458 and 7,422,211, commonly assigned to the assignee of record herein, namely Xerox Corporation, the disclosures of which are each incorporated herein by reference. While these systems particularly relate to printing systems, similar paper handling techniques apply to other media handling assemblies. Such contemporary systems transport a sheet and deliver it at a target time to a target location, based on measurements from the sheet sensors. The target location can be a particular point in a transfer zone, a hand-off point to a downstream nip assembly or any other target location within the media handling assembly. Typically, based on sheet sensor measurements, a controller can adjust the sheet velocity to steer the sheet to a target location at a desired time. The controller uses the differential drive system to correct primarily for skewed positional errors detected for the sheet. Temporarily driving two motors at slightly different rotational speeds induces a rotational sheet motion that is used to eliminate/correct for detected skew and/or process timing errors. The resultant dynamics are nonlinear and make closed-loop feedback control complex and difficult to execute.
[0006] Other contemporary systems use alternative cross-process correction techniques, such as nip assemblies that translate laterally in order to shift the sheet while engaged within the nips. However, laterally translating nip assemblies include driven wheels mounted on a moveable carriage assembly. Driven wheels inherently include motors, gears and/or belts associated therewith, thus such assemblies are complex, costly, prone to mechanical failure and difficult to repair. Also, having to reset the mechanical carriage between sheets limits the speeds and inter-copy gaps at which the system can function.
[0007] Another alternative system uses nip assemblies with fixed angled driven wheels that drive the sheets into a straight edge fence or rail, thereby correcting both cross-process and skew errors simultaneously. However, such systems are limited in the size and type of substrate media being handled and are prone to marking, buckling or damaging the substrate media.
[0008] Accordingly, it would be desirable to provide an apparatus for and a method of registering the lateral position of a sheet in a media handling assembly, which overcomes the shortcoming of the prior art.
SUMMARY
[0009] According to aspects described herein, there is disclosed an apparatus for laterally registering a sheet moved in a process direction along a transport path in a media handling assembly. A lateral direction extends perpendicular to the process direction. The assembly including at least two nip assemblies spaced apart from one another along a first axis extending in the lateral direction. Each nip assembly including a driven wheel and an idler roller. The driven wheel rotatably supported about the first axis and the idler roller cooperating with the driven wheel to engage the sheet there between. The idler roller rotatably supported about a second axis, with the second axis being selectively moveable between a first and second orientation while the sheet is moved along the transport path. In the first orientation, the second axis extending parallel to the first axis, and in the second orientation the second axis extending at an oblique angle to the first axis. The selective movement of the second axis pivoting about a third axis substantially extending through a centerline common to both the driven wheel and the idler roller of each nip assembly.
[0010] Additionally, the selective movement of at least one of the at least two nip assemblies can be independent from the selective movement of another of the at least two nip assemblies. The selective movement of the at least two nip assemblies can occur in unison. In the second orientation the oblique angle can be limited to not exceed approximately 10 degrees. Also, at least one of the at least two nip assemblies can be disposed in the first orientation while another of at least two nip assemblies can be disposed in the second orientation. Further, a first surface material of the drive wheel can be more compliant than a second surface material of the idler roll.
[0011] Also, the apparatus can include a linkage mechanism coupling the idler rollers of the at least two nip assemblies for the selective movement in unison. Additionally, the apparatus can include a controller for actuating the idler roller to move between the first orientation and the second orientation. Further, the apparatus can include at least one sensor for detecting a lateral position of the sheet. Further still, the apparatus can include a differential drive system operatively connected to the driven wheels of at least two nip assemblies. The differential drive system can impart different rotational velocities to each driven wheel.
[0012] According to other aspects described herein, there is a method of registering a lateral position of a sheet moved substantially in a process direction along a transport path in a media handling assembly. A lateral direction extending perpendicular to the process direction. The method including providing at least two nip assemblies, where each nip assembly includes a driven wheel and an idler roller. The driven wheel being rotatably supported about a first axis extending in the lateral direction. The idler roller cooperating with the driven wheel to engage the sheet there between. The idler roller being rotatably supported about a second axis. Also, the method including pivoting the idler roller about a third axis substantially extending through a centerline common to both the driven wheel and the idler roller. Whereby the second axis of rotation pivots between a first and second orientation. In one of the first and second orientations the second axis extends parallel to the first axis and in the other of the first and second orientations the second axis extends oblique to the first axis.
[0013] Additionally, the idler roller pivoting of at least one of the at least two nip assemblies can be independent from the idler roller pivoting of another of the at least two nip assemblies. Also, the method can further include measuring a lateral position of the sheet during and/or after the idler roller pivoting for continuous pivotal adjustment of the idler roller. The at least two nip assemblies can be spaced apart from one another along the first axis. The idler roller pivoting of the at least two nip assemblies can occur in unison. Further, an actuating linkage mechanism can be provided for pivoting the at least two nip assemblies in unison. Further still, each idler roller of the at least two nip assemblies can pivot a different degree of rotation. The method can further include driving a first driven wheel of the at least two nip assemblies at a different rotational speed than a second driven wheel of the at least two nip assemblies for imparting a rotational skew velocity to the sheet.
[0014] These and other aspects, objectives, features, and advantages of the disclosed technologies will become apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a partially schematic isometric view of two nip assemblies for laterally registering a sheet in a media handling assembly in accordance with an aspect of the disclosed technologies.
[0016] FIG. 2 is a side view of a basic nip assembly.
[0017] FIG. 3 is a top view of the nip assembly of FIG. 2 .
[0018] FIG. 4 is a top view of the nip assembly of FIG. 2 , with an idler roller skewed relative to the driven wheel in accordance with an aspect of the disclosed technologies.
[0019] FIG. 5 is a plan view of an adjustable idler assembly in accordance with an aspect of the disclosed technologies.
[0020] FIG. 6 is a plan view of the assembly of FIG. 5 , with the idler rollers skewed relative to the driven wheels in accordance with an aspect of the disclosed technologies.
[0021] FIG. 7 is a plan view of the assembly of FIG. 6 in conjunction with a system controller, sensors and a handled sheet in accordance with an aspect of the disclosed technologies.
[0022] FIG. 8 is a schematic block diagram of a lateral registration control method in accordance with an aspect of the disclosed technologies.
DETAILED DESCRIPTION
[0023] Describing now in further detail these exemplary embodiments with reference to the Figures, as described above the accurate sheet registration system and method are typically used in a select location or locations of the paper path or paths of various conventional media handling assemblies. Thus, only a portion of an exemplary media handling assembly path is illustrated herein.
[0024] As used herein, a “printer,” “printing assembly” or “printing system” refers to one or more devices used to generate “printouts” or a print outputting function, which refers to the reproduction of information on “substrate media” for any purpose. A “printer,” “printing assembly” or “printing system” as used herein encompasses any apparatus, such as a digital copier, bookmaking machine, facsimile machine, multi-function machine, etc. which performs a print outputting function.
[0025] A printer, printing assembly or printing system can use an “electrostatographic process” to generate printouts, which refers to forming and using electrostatic charged patterns to record and reproduce information, a “xerographic process”, which refers to the use of a resinous powder on an electrically charged plate record and reproduce information, or other suitable processes for generating printouts, such as an ink jet process, a liquid ink process, a solid ink process, and the like. Also, such a printing system can print and/or handle either monochrome or color image data.
[0026] As used herein, “substrate media” refers to, for example, paper, transparencies, parchment, film, fabric, plastic, photo-finishing papers or other coated or non-coated substrates on which information can be reproduced, preferably in the form of a sheet or web. While specific reference herein is made to a sheet or paper, it should be understood that any substrate media in the form of a sheet amounts to a reasonable equivalent thereto. Also, the “leading edge” of a substrate media refers to an edge of the sheet that is furthest downstream in the process direction. The “lateral edge” or “lateral edges” of the substrate media refers to one or more of the opposed side edges of the sheet, extending substantially in the process direction.
[0027] As used herein, a “media handling assembly” refers to one or more devices used for handling and/or transporting substrate media, including feeding, printing, finishing, registration and transport systems.
[0028] As used herein, “sensor” refers to a device that responds to a physical stimulus and transmits a resulting impulse for the measurement and/or operation of controls. Such sensors include those that use pressure, light, motion, heat, sound and magnetism. Also, each of such sensors as refers to herein can include one or more point sensors and/or array sensors for detecting and/or measuring characteristics of a substrate media, such as speed, orientation, process or cross-process position and even the size of the substrate media. Thus, reference herein to a “sensor” can include more than one sensor.
[0029] As used herein, “skew” refers to a physical orientation of a substrate media relative to a process direction. In particular, skew refers to a misalignment, slant or oblique orientation of an edge of the substrate media relative to a process direction.
[0030] As used herein, the terms “process” and “process direction” refer to a process of moving, transporting and/or handling a substrate media. The process direction is a flow path (also described as a transport path) the substrate media moves in during the process. A “cross-process direction” is perpendicular to the process direction and generally extends parallel to the web of the substrate media.
[0031] FIG. 1 depicts a partially schematic isometric view of an apparatus for laterally registering a sheet handled in a printing system. It should be noted that the partially schematic drawings herein are not to scale. In FIG. 1 , the process direction 10 corresponds to the primary direction of flow of the sheet 5 , indicated by a large arrow, heading from an upstream location toward a downstream location. The cross-process or lateral direction 15 extends perpendicular to the process direction. In this way, the sheet 5 generally travels across a pair of nip assemblies 30 toward a transfer area 20 . It should be understood that transfer area 20 , could include an image transfer system, such as the belt shown, an image transfer drum or other media handling assembly not limited to image transfer systems. Each nip assembly 30 includes a driven wheel 41 and idler roller 51 that cooperate to engage the sheet 5 there between, thereby moving the sheet 5 in the overall assembly. The driven wheel 41 is rotatably driven by a motor assembly coupled thereto by gears, belts, pulleys or other known methods. The idler roller 51 is rotatably mounted to freely rotate as a sheet 5 engages it and passes through the nip 30 . In order to grab and/or engage the sheet 5 , one or both of the driven wheel 41 and idler roller 51 are biased toward one another, such as the biasing force 45 shown.
[0032] FIG. 2 shows a side view of a basic nip assembly 30 , which includes a driven wheel 41 that cooperates with an idler roller 51 to induce sheet velocity 11 . The driven wheel 41 includes an outer surface material 43 that is generally softer or more compliant than the inner drive roller 42 or the idler roller 51 . For example, the outer surface material 43 can be silicone rubber or a similarly compliant material. In contrast, the idler roller 51 can be formed of a less compliant surface, such as a hard metal. As in contemporary systems, the driven wheel 41 , and more particularly the drive roller 42 is coupled to a drive mechanism that is regulated by a programmable and/or automated controller (not shown). The diameter or width of the individual drive or idler rollers can be varied as desired and/or as necessary for the particular application. It is generally understood in the media handling arts that the sheet velocity 11 can differ from the drive roller velocity 44 due to the compliance of the elastomer of the outer surface material 43 . In contrast, the less compliant idler roller velocity 54 is driven by frictional forces between the sheet and the hard roller 51 surface. Thus, the idler roller velocity 54 for a hard surface idler roller 51 generally matches or is generally closer to the sheet velocity 11 , than the drive roller velocity 44 . Alternatively, the idler roller 51 could be coated or provided with a soft or compliant outer surface. In one such alternative arrangement, the compliant idler roller 51 can still be less compliant than the driven wheel. In a further alternative embodiment, the more compliant outer surface material is only used on the idler roller 51 , with a less compliant or non-compliant (hard) driven wheel 41 .
[0033] FIGS. 3 and 4 depict a top view of the basic nip assembly 30 . FIG. 3 shows the idler roller 51 in different orientations than that shown in FIG. 4 , relative to the driven wheel 41 . It should be noted that the widths of the driven wheel 41 and idler roller 51 are shown to be drastically different for illustrative purposes. The actual widths are a matter of design choice. In FIG. 3 , the driven wheel 41 includes a rotational axis 40 that is parallel to the rotational axis 50 of the idler roller 51 . Due to the top view orientation of FIG. 3 , the two rotational axis 40 , 50 appear as a single axis, however their offset relationship is more clearly shown in FIG. 1 . In particular, FIG. 1 shows the rotational axis 40 of both drive wheels 41 being offset (vertically in the configuration shown) from both idler roller rotational axis 50 , although they remain parallel. In FIG. 4 , the idler roller 51 has been pivoted about an axis extending substantially through a centerline common to both the driven wheel 41 and the idler roller 51 , in accordance with an aspect of the disclosed technologies. In the top view orientation shown in FIG. 4 , the pivoting axis extends directly into and out from the page. The pivoting axis is generally perpendicular to both the process direction 10 and the lateral direction 15 . As shown in FIG. 1 , the pivoting axis 55 extends vertically, which is perpendicular to the horizontal sheet path shown. A non-horizontal sheet path would mean the axis 55 extends in a non-vertical direction, but still perpendicular to both the process direction and the lateral direction. With regard to FIG. 4 , the pivoted idler roller 51 creates an angle α between the driven wheel rotational axis 40 and the idler roller rotational axis 50 . Thus, when angle α is not zero, the idler axis 50 is said to be at an oblique angle to the driven wheel axis 40 . The same angle α is thereby created between the process direction 10 and idler velocity vector 12 .
[0034] By changing the angle α between the driven wheel rotational axis 40 and the idler roller rotational axis 50 , lateral sheet correction can be achieved. Also, such induced lateral sheet motion is decoupling motion from the process and/or skew direction motions generated by traditional systems. In accordance with an aspect of the disclosed technologies, the more compliant driven wheel 41 imparts a process direction movement, while the less compliant angled idler rollers 51 translate that process direction movement into a lateral component imparted by velocity vector 12 . The angled idler rollers 51 thus create “nip and paper dynamics” that can be used for lateral registration correction. Also, by pivoting the idler roller axis 50 relative to the driven wheel axis 40 , on a sheet-by-sheet basis, lateral registration can be maintained for each sheet even though lateral sheet drift can vary among sheets. A similar but somewhat different nip and paper dynamics can be achieved by switching the more compliant sheet engagement surface to the idler rollers. As long as the axis of rotation of the driven wheel and/or the idler roller can be changed relative to one another, so that they no longer rotate on parallel axis, lateral sheet movement can be induced.
[0035] As the angle α is increased from zero, the rate of induced sheet lateral movement should also increase. However, when a hard non-compliant roller or wheel is used, the rate of induced sheet lateral movement will reach a peak or limit once the angle α gets too large. Thus, depending on the materials used for the nip sheet engagement surfaces, the angle α can have a limit value after which no additional increase in the rate of lateral movement for the sheet can be induced. This is mainly due to sheet slippage with the low coefficient of friction non-compliant nip engagement surfaces. Additionally, the composition and texture of the sheet, as well as the sheet velocity can also effect such a limit value for the angle α. Accordingly, it can be advantageous to limit how much pivot about the pivoting axis 55 is allowed to be actuated between the driven wheel 41 and the idler roller 51 . Thus, a predesignated limit value can be assigned or set for a maximum oblique angle α.
[0036] FIGS. 5 and 6 depict a linkage mechanism 60 for adjusting idler angles of both nip assemblies in unison. The linkage mechanism 60 includes individual idler frames 62 for each idler roller 51 . The idler frames 62 are shown as a rectangular rigid structure with a central shaft 63 rotationally supporting the idler roller 51 . Each of these central shafts 63 coincide with the idler roller axis 50 , discussed with regard to FIGS. 1 , 3 and 4 . Also, opposed sides of the idler frame 62 include a pivotal coupling joint 64 for linking the two idler frames 62 in order for them to move in unison. The use of further linkage bars 65 , 66 and coupling joints 64 link the two frames 62 . Thus, opposed sides of the frames 62 include process direction linkage bars 65 . Each of the process direction linkage bars 65 is pivotally connected through a coupling joint 64 , on one side by the frame 62 and on its opposite side by a lateral linkage bar 66 . The lateral linkage bars 66 are pivotally coupled through a coupling joint 64 at opposed ends by process direction linkage bars 65 that connect to separate frames 62 . By providing a mechanism (not shown) for inducing opposite lateral 15 movement of the two linkage bars 66 , the frames 62 will pivot. Thus, as shown in FIG. 6 , by shifting the right side (downstream side) lateral linkage bar 66 upwardly and the left side (upstream side) lateral linkage bar 66 downwardly, both frames 62 pivot. Accordingly, once the frames 62 are pivoted relative to the driven wheels 41 , the idler velocity vector 12 is no longer parallel with the process direction and will thus induce lateral sheet movement. It should be understood that although a rectangular and/or linear linkage mechanism structure is shown, alternative structures can be used to achieve the same or similar unified movement.
[0037] FIG. 7 depicts an alternative embodiment registration system 100 where the individual idler frames 62 are not coupled to one another, but rather are separately actuated by a controller 70 . FIG. 7 also shows a sheet 5 conveyed in the process direction 10 through two nip assemblies used in conjunction with edge sensors 22 , 24 , all coupled to a controller 70 . Edge sensors 22 , 24 can be used to detect the lateral and process position, as well as orientation, of the sheet 5 relative to the nip assemblies. While two sensors 22 , 24 are shown, it should be understood that fewer or greater numbers of sensors could be used, depending on the type of sensor, the desired accuracy of measurement and redundancy needed or preferred. For example, a pressure or optical sensor could be used to detect when the lateral edge of the sheet passes over each individual sensor. Additionally, the sensors can be positioned further upstream or closer to the nip assemblies, as desired. It should be appreciated that any sheet sensing system can be used to detect the position and/or other characteristics of the substrate media in accordance with the disclosed technologies. Once the actual lateral sheet position is measured by the sensors 22 , 24 , the controller 70 can actuate one or both of the idler frames 62 in order to correct the lateral sheet position. In the previous embodiment where both idler frames 62 moved in unison, the controller 70 would actuate the linkage mechanism 60 to correct the lateral sheet position.
[0038] Additionally, by measuring the sheet lateral position at the sensors 22 , 24 and knowing the spacing of the sensors 22 , 24 , skew of the sheet 5 relative to the nip assemblies 30 can be calculated, as is known in the art. Alternatively, a similar skew orientation of the sheet 5 can be detected by other sensor systems, disposed upstream of the nips 30 . For example, a pair of point sensors or one or more array sensors capable of measuring sheet position and/or skew can alternatively be provided.
[0039] A controller 70 is used to receive sheet information from edge sensors 22 , 24 and any other available input that can provide useful information regarding the sheet(s) 5 being handled in the system. The controller 70 can include one or more processing devices capable of individually or collectively receiving signals from input devices, outputting signals to control devices and processing those signals in accordance with a rules-based set of instructions. The controller 70 can then transmit signals to one or more actuation systems. For example a rack and gear assembly could be actuated by the controller 70 in order to shift the configuration of the idler frames 62 between that shown in FIGS. 5 and 6 . Also, the controller 70 can activate a differential drive system for correcting skew or process speeds. Thus, based on the position/orientation of the sheet input into the controller 70 , a “correction profile” is calculated to eliminate the detected positional and/or timing error(s).
[0040] FIG. 8 shows a schematic block diagram of a lateral registration control method used in accordance with an embodiment of the disclosed technologies. The registration method includes a predesignated or desired sheet position for proper registration within the system. Such positional information particularly includes lateral sheet position, but can additionally include sheet skew and process position/timing information. The method initiates at 80 when a lateral sheet position error is noted as compared to the predesignated lateral sheet position. The controller 70 is provided with a lateral sheet position measurement, such as from edge sensors 22 , 24 , which indicates the noted error. Additionally, the lateral edge sensors 22 , 24 can provide controller 70 with skew and/or process position measurements. The controller 70 then acts to correct the measured lateral positioning error by transmitting a command to angle the idler rollers 51 relative to the driven wheels 41 . Preferably, the idler rollers 51 can be angled in either lateral direction (inboard or outboard) relative to the process direction. Both of the idler rollers 51 can be pivoted by the same angle in unison through a linkage mechanism or independently pivoted the same amount. The angle α of the idler rollers is selected based on the amount of lateral movement needed to correct the sheet position. Alternatively, a predesignated idler roller angle α can be used, such as 10 degrees, with the duration of such angling varied to achieve the amount of desired lateral movement. As the idler rollers 51 achieve the desired angle the nips 30 will induce lateral movement through a nip and paper dynamics 85 in accordance with an aspect of the disclosed technologies.
[0041] As yet a further alternative, independently pivoting idler rollers 51 can be angled differently in order to also induce or remove/prevent buckling of the sheet 5 . If the idler velocity vectors 12 of the two idler rollers 51 are angled slightly away from one another, it will remove/prevent buckling, whereas if they are angled toward one another it will induce buckling or relieve lateral tension on the sheet.
[0042] While the sheet 5 is still engaged by the nips 30 and at least one sensor 22 , 24 is still able to register a lateral position for the sheet, such sheet position information can be further correlated to the predesignated lateral position. By continually monitoring sheet position using the sensors 22 , 24 a closed-loop feedback regarding positional errors can be provided to the controller 70 . The controller 70 can thus continue to make adjustments to the idler angle(s) as needed. Further, by providing additional downstream sensors (not shown) measuring lateral and/or skew position, the closed-loop feedback can be provided to controller 70 over a greater length of the sheet in order to make continuous adjustments to the skew and/or lateral position while the sheet remains engaged by the nips 30 . Once the sheet is no longer engaged by the nips 30 , the idler angle(s) can be returned to zero or another default angle value for the next approaching sheet.
[0043] In addition to lateral position correction, other registration correction systems such as a differential drive system can be used to perform skew and/or process timing corrections. It should be understood that such skew, process and lateral adjustments can occur in any order or can occur at or near the same time. During any adjustment of skew, cross-process or process positioning or timing, any downstream nips are preferably opened to allow the sheet 5 to be adjusted more freely.
[0044] Often media handling assembly, and particularly printing systems, include more than one module or station. Accordingly, more than one registration system 100 as disclosed herein can be included in an overall media handling assembly. Further, it should be understood that in a modular system or a system that includes more than one registration system 100 , in accordance with the disclosed technologies herein, could detect sheet position and relay that information to a central processor for controlling registration, including lateral position and skew in the overall media handling assembly. Thus, if the sheet positional errors are too large for registration system 100 to correct, then correction can be achieved with the use one or more subsequent downstream registration systems 100 , for example in another module or station.
[0045] It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims. | An assembly including two nip assemblies spaced apart along a first axis. Each nip assembly including a driven wheel and an idler roller. The driven wheel rotatably supported about the first axis. The idler cooperating with the driven wheel to engage a sheet. The idler rotatably supported about a second axis. The second axis being selectively moveable relative to the first axis. The selective movement between a first and second orientation while the sheet is moved along the transport path. In the first orientation the second axis extends parallel to the first axis. In the second orientation the second axis extends at an oblique angle to the first axis. The selective movement pivoting about a third axis extending through a centerline common to both the driven wheel and the idler. The selective movement of one of the two nip assemblies being independent from the selective movement of the other. | 1 |
RELATED APPLICATIONS
This application is a continuation of pending prior application Ser. No. 8/003,200, filed Jan. 11, 1993, of Franklin S. Love, III and Robert Saul Brown for METHOD AND APPARATUS FOR TREATMENT OF PILE FABRIC.
BACKGROUND OF THE INVENTION
This invention relates to an improved method and apparatus for removing pile distortions in fabric created by heat-setting and/or dyeing.
In the case of pile fabrics, which have been heat-set at a high temperature with the pile erect and then dyed at a lower temperature during which the pile is substantially disturbed, as in jet dyeing, it is then desired to have the pile return to its original erect condition. One attempt in solving this problem is the tensionless dryer. In this machine, the pile fabric is fed onto a mesh belt that is then transported through a long heated tunnel where either mechanical action or perpendicular air blasts directed at the belt cause the fabric to undergo rather gentle undulations. The fabric is statically charged by friction with the air or contact with various parts of the dryer. The required processing time results in a drying unit over one hundred feet long with a low fabric line speed. There are quality problems associated with a lack of control over the fabric for such a long distance and well as marks that occur when the fabric strikes the upper section of the tunnel.
Another type of pile conditioning device is the use of a high velocity air jet such as U.S. Pat. No. 4,837,902.
In this case, the fabric is heated to the desired temperature and the conditioning is accomplished almost instantaneously by vigorous sawtoothed shaped waves that are small in amplitude, but effective due to high accelerations normal to the fabric surface produced by the wave's small bending radius and high velocity. The disadvantage of this process is direct contact of the heated fabric with the air stream, which tensions the fabric and can set in distortions in sensitive knit fabrics. Also, this process is less effective with highly permeable fabrics, as the air may not be trapped between the fabric and plate.
Yet another type of device vibrates and charges the pile fabric in the heated condition by contact with pneumatically excited diaphragms. The contact of the fabric with the diaphragms combined with the rapid vibrations induced by the air stream cause the diaphragm to wear out at a rate in which replacement can be a daily occurrence.
Still another type of device vibrates and charges the pile fabric biaxially by means of a rotating cylindrical roll with spaced protrusions or depressions along the exterior surface of the cylinder, followed by optionally vibrating the fabric axially by means of a second rotating cylindrical roll having flat portions continuously extending along the longitudinal axis of the second cylinder. The repeated and rapid front to back and side to side movement of individual pile fibers caused by multiple vibrational waves during biaxial treatment allows the fibers to return to their preferred heat-set orientation.
The present invention solves the above problems in a manner not disclosed in the known prior art.
SUMMARY OF THE INVENTION
A method and apparatus for continuous treatment of webs of fabric having upright pile comprised of wetting the fabric to at least 50% saturation, heating the fabric to approximately 225° to 350° Fahrenheit and then brushing the fabric in both the pile and counter-pile directions. The presence of liquid and steam plasticize and lubricate the fibers, thereby allowing an easier, more complete return to the uncrushed state.
An advantage of this invention is that it does not require the high temperatures of dry face finishing and also results in a less cloudy or a more clear face finish.
It is another advantage of this invention that it is able to work on wet fabrics so that jet-dyed pile fabrics straight from the dye jet are able to be treated without the need for intermediate drying. This not only reduces processing costs but also reduces wear and tear on the fabric by eliminating a costly pass down a tenter range utilized for drying.
Another advantage of this invention is that the treatment is completely uniform without any highlights.
Still another advantage of this invention is that the crushed pile might be in any direction and will be processed and come out in only one solitary direction.
Another advantage of this invention is that there is a blooming of tuft which provides a cover effect and fullness. It also creates a greater softness in the fabric due to the spreading out of the tuft.
Yet another advantage of this invention is that the fabric may be dried at the same time as treated. This will eliminate another processing step.
Yet another advantage of this invention is that it will allow face finishing of lower melting point fibers such as polypropylene and polyethylene. It is more effective in the transference of treatment to the fabric.
Still another advantage to this invention is that it is very effective with less point contact.
These and other advantages will be in part apparent and in part pointed out below.
BRIEF DESCRIPTION OF THE DRAWINGS
The above, as well as other objects of the invention, will become more apparent from the following detailed description of the preferred embodiments of the invention, which when taken together with the accompanying drawings, in which:
FIG. 1 is a diagrammatic side elevational view of the apparatus constructed according to the present invention with the fabric being initially saturated with liquid and then heated and brushed by a series of four units in both directions in order to restore the pile;
FIG. 2 is an elevational side view of a first mechanism for heating and brushing pile fabric;
FIG. 3 is an elevational side view of a second mechanism for heating and brushing fabric;
FIG. 4 is an elevational side view of a third mechanism for heating and brushing fabric;
FIG. 5 is an elevational side view of a fourth mechanism for heating and brushing fabric;
FIG. 6 is an elevational side view corresponding to FIG. 4 only that it represents the opposite side of the third mechanism for heating and brushing pile fabric;
FIG. 7 is an isolated side view of the brushing mechanism as shown in FIG. 2;
FIG. 8 is a blown-up view of a primary fifth steam roll, pile fabric and roller brush and the relationship thereof; and
FIG. 9 is a cross-section taken through the middle of the third mechanism for heating and brushing fabric as shown in FIG. 4.
Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now by reference numerals to the drawings, and first to FIG. 1, assembly to erect pile fabric is generally indicated by numeral 2. The pile fabric 8 is initially removed, with the pile side down, from a buggy 4 movably supported by four rollers 6. The pile fabric 8 is then directed angularly upward by a first idler roll 10 and then angularly downward through second idler roll 12 which submerges the pile fabric 8 in a container of liquid 16. This liquid can be any variety of chemicals, however, water is preferred. Furthermore, the temperature of the liquid is not critical and can range from between above freezing to boiling. The container of liquid 16 is held in place by a support frame 14. The pile fabric 8 then passes through a pair of nip rolls 18 and 20, respectively. The pile fabric 8 then passes by a vacuum slot 24 having a tube mechanism 22 for expelling the stream of air. This will remove trapped liquid from the pile fabric, leaving it at 100% saturation with no entrapped liquid. However, this does not have to be 100% saturation and can be anything above 50%. The pile fabric 8 then moves vertically upward and then passes over idler roll 26 and onward to the first heating and brushing mechanism generally indicated by numeral 100.
Referring now to FIGS. 1-9, all four heating and brushing mechanisms have identical frame structures. Identical components will only differ by the first number with numbers in the nine hundred series being identical for all heating and brushing mechanisms. This rectangular structure has a pair of left vertical members 134 and a pair of right vertical members 168 and a pair of top horizontal members 151 and a pair of bottom horizontal members 136 with a pair of middle horizontal members 135 in between, as shown in FIG. 2. As shown in FIG. 9, each opposed end of left vertical members 534 have a pair of lateral support braces 667, 650 and located at each opposed end of right vertical members 568 are a pair of lateral support braces 668, 681, respectively.
Attached to the top horizontal members 551 are a pair of upper left vertical members 501 with lateral support brace 682 located at the upper end thereof. There is a pair of upper right vertical members 565 with lateral support brace 689 located at the middle of the upper right vertical members 565. There is a pair of upper middle horizontal support members 538 located between the upper left vertical members 501 and upper right vertical members 565 with a lateral support brace 684 located therebetween.
As shown in FIG. 2, upper right vertical members 165 are attached to the top horizontal members 151 by means of bolts 166 and 167 through plates 169 and 164. Upper left vertical members 101 are attached to the top horizontal members 151 by means of bolts 172 and 173 through plates 171 and 170.
Referring again specifically to the first heating and brushing mechanism generally indicated by numeral 100, as shown in FIG. 2, the pile fabric 8 passes through an upper directing idler roll 105. There is a pair of bearing members 106 rotatably attached to upper directing idler roll 105. Each bearing member 106 are bolted to an adjustment member 102 by means of bolts 104 and 107. There are two adjustment mechanisms 103 and 108 for each bearing member 106, which uses a combination of flanges attached to adjustment member 102 and a threaded bolt with nuts on each side of the flanges attached to the adjustment member 102 to shift upwardly directing idler roll 105 vertically along upper left vertical member 101. Adjustment member 102 is fixedly attached to upper left vertical member 101. The pile fabric 8 then goes around the outside of first steam roll 117. First steam roll 117 is rotatably attached to upper left vertical member 101 by means of a pair of bearing members 115 that are attached to a first steam roll mounting plate 111 by means of bolts 113 and 118, respectively. The first steam roll mounting plate 111 is attached to a first steam roll adjustment member 109 by a pair of bolts 112 and 116. The first steam roll adjustment member 109 has a pair of flanges and there are two first steam roll adjustment mechanisms 110 and 120 which in conjunction with bolts and nuts operating on the flanges as previously described allow the steam roll 117 to shift vertically along upper left vertical member 101. There are two first steam plate bearing members 115 with another identical member on the other side of first steam roll 117 which is not shown and serves to hold first steam roll 117 in a rotatable position. There is a first steam roll input 114 to introduce water vapor into first steam roll 117 as well as a first steam roll condensate tube 116 to remove condensed liquid from first steam roll 117.
Pile fabric 8 then travels around the outside perimeter of second steam roll 147. Second steam roll 147 is rotatably attached to upper middle horizontal support members 138 by means of a pair of bearing members 144. Bearing members 144 are attached to a second steam roll mounting plate 141 by means of bolts 143 and 148, respectively. The second steam roll mounting plate 141 is attached to a second steam roll adjustment member 139 by a pair of bolts 149 and 142. The second steam roll adjustment member 139 has a pair of flanges and there are two first steam roll adjustment mechanisms 140 and 150 which in conjunction with bolts and nuts operating on the flanges as previously described allow the second steam roll 147 to shift horizontally along upper middle horizontal support members 138. There are two second steam plate bearing members 144 with another identical member on the other side of second steam roll 147 which is not shown and serves to hold second steam roll 147 in a rotatable position. There is a second steam roll input 145 to introduce water vapor into second steam roll 147 as well as a second steam roll condensate tube 146 to remove condensed liquid from second steam roll 147.
The pile fabric 8 then goes around the outside of third steam roll 129. Third steam roll 129 is rotatably attached to upper left vertical member 101 by means of a pair of bearing members 127 that are attached to a third steam roll mounting plate 123 by means of bolts 125 and 130, respectively. The third steam roll mounting plate 123 is attached to a third steam roll adjustment member 121 by a pair of bolts 124 and 131. The third steam roll adjustment member 121 has a pair of flanges and there are two third steam roll adjustment mechanisms 122 and 132 which in conjunction with bolts and nuts operating on the flanges as previously described allow the third steam roll 129 to shift vertically along upper left vertical member 101. There are two third steam plate bearing members 127 with another identical member on the other side of third steam roll 129 which is not shown and serves to hold third steam roll 129 in a rotatable position. There is a third steam roll input 126 to introduce water vapor into third steam roll 129 as well as a third steam roll condensate tube 128 to remove condensed liquid from third steam roll 129.
Pile fabric 8 then travels around the outside perimeter of fourth steam roll 160. Fourth steam roll 160 is rotatably attached to top horizontal support members 151 by means of a pair of bearing members 157. Bearing members 157 are attached to a fourth steam roll mounting plate 154 by means of bolts 156 and 161, respectively. The fourth steam roll mounting plate 154 is attached to a fourth steam roll adjustment member 152 by a pair of bolts 155 and 162. The fourth steam roll adjustment member 152 has a pair of flanges and there are two fourth steam roll adjustment mechanisms 153 and 163 which in conjunction with bolts and nuts operating on the flanges as previously described allow the fourth steam roll 160 to shift horizontally along top horizontal support members 151. There are two fourth steam plate bearing members 157 with another identical member on the other side of fourth steam roll 160 which is not shown and serves to hold fourth steam roll 160 in a rotatable position. There is a fourth steam roll input 158 to introduce water vapor into second steam roll 160 as well as a fourth steam roll condensate tube 159 to remove condensed liquid from fourth steam roll 160.
The pile fabric 8 then travels around fifth steam roll 202 which is the primary steam roll that is used in conjunction with the brushing action. This is rotatably attached by means by a pair of bearing mechanisms 201 which are held by bolts 203 and 204 to horizontal support member 198 which has a left horizontal member 196 and a right horizontal member 197 attached thereto which connect to the underside of top horizontal member 151, respectively. There are a pair of adjustment mechanisms 205 and 206, respectively to be able to shift fifth steam roll 202 horizontally. There is also a fifth steam input 199 and steam condensate tube 200 associated with the fifth primary steam roll 202. There are two brushing mechanisms shown on the left and right of fifth steam roll 202 which are identical, but reversed.
The brushing mechanism on the left has a first housing frame 179 that is connected to a pair of pivot shafts 226 that are rotatably supported in a pair of pivot members 191. Pivot members 191 are attached to adjustment member 195 by means of bolts 192 and 193, respectfully and having an adjustment mechanism 194, as previously described for horizontal movement of the pivot shafts 226 along middle horizontal members 135.
The brushing mechanism on the right has a second housing frame 299 that is connected to a pair of pivot shafts 225 that are rotatably supported in a pair of pivot members 227. Pivot members 227 are attached to adjustment member 210 by means of bolts 228 and 229, respectfully and having an adjustment mechanism 211, as previously described for horizontal movement of the pivot shafts 225 along middle horizontal members 135.
There is a positioning bracket 188 that allows the first housing frame 179 to come back to the exact same position for the same degree of brush penetration. There is an adjustable stop 187 that is connected to the positioning bracket 188 that can be moved toward and away from the face of the positioning bracket 188 to adjust the stop of the first housing frame 179. The adjustable stop 187 will abut an eccentric cam 133 when in position. As shown on the right brushing mechanism, the eccentric cam 133 is mounted on a shaft 222 that is connected to a pulley 221 that is moved by means of an endless belt 220 that is connected to a secondary pulley 219 that is rotated by a hand crank 218 having a pin mechanism to lock the hand crank 218 into position. There is another adjustment mechanism 213 that moves secondary pulley 219 to place tension on endless belt 220. Adjustment mechanism 213 is mounted to the second housing frame 299 by a series of three bolts 214.
There is a motor 180 which drives the system having a pulley 181 and endless belt mechanism 182. This endless belt mechanism 182 drives cylindrical brush 184 by means of attached pulley 1184. Cylindrical brush 184 is rotatably attached to bearing plates 223 that are attached by means of four bolts 190. Endless belt mechanism 182 also drives a cleaning roll 183 with associated pulley 224 the removes lint and debris from the cylindrical brush 184. Cylindrical brush 184 has bristles that can be of any length and only need to contact the fabric between just barely touching the fabric to almost touching the backing of the fabric. The preferred length of bristles is 0.25 to 1.75 inches. It is preferable that these bristles are of stainless steel or of some other non-corrosive material. These bristles also can be coated. The density of the bristles depend on the effect desired and the type of pile fabric brushed. Cleaning roll 183 needs to be able to engage the bristles of cylindrical brush 184. Both cylindrical brushes 184 will engage the fabric that is passed around the outside of the fifth steam roll 202. The preferred r.p.m. of the cylindrical brushes is a range of 500 to 600 with a possible range of 0 to 3000.
The pile fabric 8 will preferably pass through this invention at a rate of thirty yards per minute, however, any speed between 0 to 250 yards per minute will work.
Motor 180 is mounted to both frame 179 and 299 by means of bolts 185 and 186 and adjustment mechanism 189. Cleaning roll 183 is mounted in a adjustable bearing assembly plate 216 with a set of four inner bolts 215 and an outer slotted plate assembly 298 with another four bolts with a pair a adjustment mechanisms 178 and 212 attached thereto.
First housing frame 179 is supported by a pin member 177 and there is an air cylinder 176 that is also pivotally mounted by means of pin 175 to a support member 174. There are four bolts 209 attached to a plate which also provides support, as also shown in FIG. 9. Support member 174 is attached to bottom horizontal member 136.
There is a shock absorber shown in FIG. 9 as numeral 670 mounted by means of four bolts 208 to plate member 207 that is attached to middle horizontal member 135. This same structure is replicated on the right hand side with second housing frame 298 supported by a pin member 297 and there is an air cylinder 296 that is also pivotally mounted by means of pin 295 to a support member 294. There are four bolts 293 attached to a plate which also provides support, as also shown in FIG. 9. Support member 294 is attached to bottom horizontal member 136. There is a shock absorber shown in FIG. 9 as numeral 671 mounted by means of four bolts 217 to plate member 216 that is attached to middle horizontal member 135.
All heating and brushing mechanisms to erect pile fabric 8 are mounted on adjustable levelers 137 utilizing dual nut with threaded bolt combination. Air cylinders 176, 376, 576, and 776 have inputs 253, 453, 653 and 853 and outputs 252, 452, 652 and 852, respectively. Air cylinders 296, 496, 696 and 896 have an inputs and 254, 454, 654 and 854 and outputs 255, 455, 655 and 855, respectively.
Pile fabric 8 then goes through lower idler roll 230 which is rotatably supported by pair of bearings 231 which is bolted by means of bolts 232 and 233 to adjustment member 234 having adjustment means 235 and 236 as previously described which attach to the underside of upper middle horizontal support member 138. Pile fabric 8 then exits the first heating and brushing mechanism 100 and enters the second brushing and heating mechanism 300 which essentially replicates heating mechanism 100 which for the sake of clarity will be described again.
Referring again specifically to the second heating and brushing mechanism generally indicated by numeral 300, as shown in FIG. 2, the pile fabric 8 passes through an upper directing idler roll 305. There is a pair of bearing members 306 rotatably attached to upper directing idler roll 305. Each bearing member 306 are bolted to an adjustment member 302 by means of bolts 304 and 307. There are two adjustment mechanisms 303 and 308 for each bearing member 306, which uses a combination of flanges attached to adjustment member 302 and a threaded bolt with nuts on each side of the flanges attached to the adjustment member 302 to shift upwardly directing idler roll 305 vertically along upper left vertical member 301. Adjustment member 302 is fixedly attached to upper left vertical member 301. The pile fabric 8 then goes around the outside of first steam roll 317. First steam roll 317 is rotatably attached to upper left vertical member 301 by means of a pair of bearing members 315 that are attached to a first steam roll mounting plate 311 by means of bolts 313 and 318, respectively. The first steam roll mounting plate 311 is attached to a first steam roll adjustment member 309 by a pair of bolts 312 and 316. The first steam roll adjustment member 309 has a pair of flanges and there are two first steam roll adjustment mechanisms 310 and 320 which in conjunction with bolts and nuts operating on the flanges as previously described allow the steam roll 317 to shift vertically along upper left vertical member 301. There are two first steam plate bearing members 315 with another identical member on the other side of first steam roll 317 which is not shown and serves to hold first steam roll 317 in a rotatable position.
There is a first steam roll input 314 to introduce water vapor into first steam roll 317 as well as a first steam roll condensate tube 316 to remove condensed liquid from first steam roll 317.
Pile fabric 8 then travels around the outside perimeter of second steam roll 347. Second steam roll 347 is rotatably attached to upper middle horizontal support members 338 by means of a pair of bearing members 344. Bearing members 344 are attached to a second steam roll mounting plate 341 by means of bolts 343 and 348, respectively. The second steam roll mounting plate 341 is attached to a second steam roll adjustment member 339 by a pair of bolts 349 and 342. The second steam roll adjustment member 339 has a pair of flanges and there are two first steam roll adjustment mechanisms 340 and 350 which in conjunction with bolts and nuts operating on the flanges as previously described allow the second steam roll 347 to shift horizontally along upper middle horizontal support members 338. There are two second steam plate bearing members 344 with another identical member on the other side of second steam roll 347 which is not shown and serves to hold second steam roll 347 in a rotatable position. There is a second steam roll input 345 to introduce water vapor into second steam roll 347 as well as a second steam roll condensate tube 346 to remove condensed liquid from second steam roll 347.
The pile fabric 8 then goes around the outside of third steam roll 329. Third steam roll 329 is rotatably attached to upper left vertical member 301 by means of a pair of bearing members 327 that are attached to a third steam roll mounting plate 323 by means of bolts 325 and 330, respectively. The third steam roll mounting plate 323 is attached to a third steam roll adjustment member 321 by a pair of bolts 324 and 331. The third steam roll adjustment member 321 has a pair of flanges and there are two third steam roll adjustment mechanisms 322 and 332 which in conjunction with bolts and nuts operating on the flanges as previously described allow the third steam roll 329 to shift vertically along upper left vertical member 301. There are two third steam plate bearing members 327 with another identical member on the other side of third steam roll 329 which is not shown and serves to hold third steam roll 329 in a rotatable position. There is a third steam roll input 326 to introduce water vapor into third steam roll 329 as well as a third steam roll condensate tube 328 to remove condensed liquid from third steam roll 329.
Pile fabric 8 then travels around the outside perimeter of fourth steam roll 360. Fourth steam roll 360 is rotatably attached to top horizontal support members 351 by means of a pair of bearing members 357. Bearing members 357 are attached to a fourth steam roll mounting plate 354 by means of bolts 356 and 361, respectively. The fourth steam roll mounting plate 354 is attached to a fourth steam roll adjustment member 352 by a pair of bolts 355 and 362. The fourth steam roll adjustment member 352 has a pair of flanges and there are two fourth steam roll adjustment mechanisms 353 and 363 which in conjunction with bolts and nuts operating on the flanges as previously described allow the fourth steam roll 360 to shift horizontally along top horizontal support members 351. There are two fourth steam plate bearing members 357 with another identical member on the other side of fourth steam roll 360 which is not shown and serves to hold fourth steam roll 360 in a rotatable position. There is a fourth steam roll input 358 to introduce water vapor into second steam roll 360 as well as a fourth steam roll condensate tube 359 to remove condensed liquid from fourth steam roll 360.
The pile fabric 8 then travels around fifth steam roll 402 which is the primary steam roll that is used in conjunction with the brushing action. This is rotatably attached by means by a pair of bearing mechanisms 401 which are held by bolts 403 and 404 to horizontal support member 398 which has a left horizontal member 396 and a right horizontal member 397 attached thereto which connect to the underside of top horizontal member 351, respectively. There are a pair of adjustment mechanisms 405 and 406, respectively to be able to shift fifth steam roll 402 horizontally. There is also a fifth steam input 399 and steam condensate tube 400 associated with the fifth primary steam roll 402. There are two brushing mechanisms shown on the left and right of fifth steam roll 402 which are identical, but reversed.
The brushing mechanism on the left has a first housing frame 379 that is connected to a pair of pivot shafts 426 that are rotatably supported in a pair of pivot members 391. Pivot members 391 are attached to adjustment member 395 by means of bolts 392 and 393, respectfully and having an adjustment mechanism 394, as previously described for horizontal movement of the pivot shafts 426 along middle horizontal members 335.
The brushing mechanism on the right has a second housing frame 499 that is connected to a pair of pivot shafts 425 that are rotatably supported in a pair of pivot members 427. Pivot members 427 are attached to adjustment member 410 by means of bolts 428 and 429, respectfully and having an adjustment mechanism 411, as previously described for horizontal movement of the pivot shafts 425 along middle horizontal members 335.
There is a positioning bracket 388 that allows the first housing frame 379 to come back to the exact same position for the same degree of brush penetration. There is an adjustable stop 387 that is connected to the positioning bracket 388 that can be moved toward and away from the face of the positioning bracket 388 to adjust the stop of the first housing frame 379. The adjustable stop 387 will abut an eccentric cam 333 when in position. As shown on the right brushing mechanism, the eccentric cam 333 is mounted on a shaft 422 that is connected to a pulley 421 that is moved by means of an endless belt 420 that is connected to a secondary pulley 419 that is rotated by a hand crank 418 having a pin mechanism to lock the hand crank 418 into position. There is another adjustment mechanism 413 that moves secondary pulley 419 to place tension on endless belt 420. Adjustment mechanism 413 is mounted to the second housing frame 499 by a series of three bolts 414.
There is a motor 380 which drives the system having a pulley 381 and endless belt mechanism 382. This endless belt mechanism 382 drives cylindrical brush 384 by means of attached pulley 1384. Cylindrical brush 384 is rotatably attached to bearing plates 423 that are attached by means of four bolts 390. Endless belt mechanism 382 also drives a cleaning roll 383 with associated pulley 424 the removes lint and debris from the cylindrical brush 384. Cylindrical brush 384 has bristles that can be of any length and only need to contact the fabric between just barely touching the fabric to almost touching the backing of the fabric. The preferred length of bristles is 0.25 to 1.75 inches. It is preferable that these bristles are of stainless steel or of some other non-corrosive material. These bristles also can be coated. The density of the bristles depend on the effect desired and the type of pile fabric brushed. Cleaning roll 383 needs to be able to engage the bristles of cylindrical brush 384. Both cylindrical brushes 384 will engage the fabric that is passed around the outside of the fifth steam roll 402. The preferred r.p.m. of the cylindrical brushes is a range of 500 to 600 with a possible range of 0 to 3000. The pile fabric 8 will preferably pass through this invention at a rate of thirty yards per minute, however, any speed between 0 to 250 yards per minute will work.
Motor 380 is mounted to both frame 379 and 499 by means of bolts 385 and 386 and adjustment mechanism 389. Cleaning roll 383 is mounted in a adjustable bearing assembly plate 416 with a set of four inner bolts 415 and an outer slotted plate assembly 498 with another four bolts with a pair a adjustment mechanisms 378 and 412 attached thereto.
First housing frame 379 is supported by a pin member 377 and there is an air cylinder 376 that is also pivotally mounted by means of pin 375 to a support member 374. There are four bolts 409 attached to a plate which also provides support, as also shown in FIG. 9. Support member 374 is attached to bottom horizontal member 336.
There is a shock absorber shown in FIG. 9 as numeral 670 mounted by means of four bolts 408 to plate member 407 that is attached to middle horizontal member 335. This same structure is replicated on the right hand side with second housing frame 498 supported by a pin member 497 and there is an air cylinder 496 that is also pivotally mounted by means of pin 495 to a support member 494. There are four bolts 493 attached to a plate which also provides support, as also shown in FIG. 9. Support member 494 is attached to bottom horizontal member 336. There is a shock absorber shown in FIG. 9 as numeral 671 mounted by means of four bolts 417 to plate member 416 that is attached to middle horizontal member 335.
All heating and brushing mechanisms to erect pile fabric 8 are mounted on adjustable levelers 337 utilizing dual nut with threaded bolt combination. Air cylinders 176, 376, 576, and 776 have inputs 253,453, 653 and 853 and outputs 252, 452, 652 and 852, respectively. Air cylinders 296, 496, 696 and 896 have an inputs and 254, 454, 654 and 854 and outputs 255, 455, 655 and 855, respectively.
Pile fabric 8 then goes through lower idler roll 430 which is rotatably supported by pair of bearings 431 which is bolted by means of bolts 432 and 433 to adjustment member 434 having adjustment means 435 and 436 as previously described which attach to the underside of upper middle horizontal support member 338. Pile fabric 8 then exits the second heating and brushing mechanism 300 and enters the third brushing and heating mechanism 500 which essentially replicates heating mechanism 300 which for the sake of clarity will be described again.
Referring again specifically to the third heating and brushing mechanism generally indicated by numeral 500, as shown in FIG. 3, 6 and 9, the pile fabric 8 passes through an upper directing idler roll 505. There is a pair of bearing members 506 rotatably attached to upper directing idler roll 505. Each bearing member 506 are bolted to an adjustment member 502 by means of bolts 504 and 507. There are two adjustment mechanisms 503 and 508 for each bearing member 506, which uses a combination of flanges attached to adjustment member 502 and a threaded bolt with nuts on each side of the flanges attached to the adjustment member 502 to shift upwardly directing idler roll 505 vertically along upper left vertical member 501. Adjustment member 502 is fixedly attached to upper left vertical member 501. The pile fabric 8 then goes around the outside of first steam roll 517. First steam roll 517 is rotatably attached to upper left vertical member 501 by means of a pair of bearing members 515 that are attached to a first steam roll mounting plate 511 by means of bolts 513 and 518, respectively. The first steam roll mounting plate 511 is attached to a first steam roll adjustment member 509 by a pair of bolts 512 and 516. The first steam roll adjustment member 509 has a pair of flanges and there are two first steam roll adjustment mechanisms 510 and 520 which in conjunction with bolts and nuts operating on the flanges as previously described allow the steam roll 517 to shift vertically along upper left vertical member 501. There are two first steam plate bearing members 515 with another identical member on the other side of first steam roll 517 which is not shown and serves to hold first steam roll 517 in a rotatable position. There is a first steam roll input 514 to introduce water vapor into first steam roll 517 as well as a first steam roll condensate tube 516 to remove condensed liquid from first steam roll 517.
Pile fabric 8 then travels around the outside perimeter of second steam roll 547. Second steam roll 547 is rotatably attached to upper middle horizontal support members 538 by means of a pair of bearing members 544. Bearing members 544 are attached to a second steam roll mounting plate 541 by means of bolts 543 and 548, respectively. The second steam roll mounting plate 541 is attached to a second steam roll adjustment member 539 by a pair of bolts 549 and 542. The second steam roll adjustment member 539 has a pair of flanges and there are two first steam roll adjustment mechanisms 540 and 550 which in conjunction with bolts and nuts operating on the flanges as previously described allow the second steam roll 547 to shift horizontally along upper middle horizontal support members 538. There are two second steam plate bearing members 544 with another identical member on the other side of second steam roll 547 which is not shown and serves to hold second steam roll 547 in a rotatable position. There is a second steam roll input 545 to introduce water vapor into second steam roll 547 as well as a second steam roll condensate tube 546 to remove condensed liquid from second steam roll 547.
The pile fabric 8 then goes around the outside of third steam roll 529. Third steam roll 529 is rotatably attached to upper left vertical member 501 by means of a pair of bearing members 527 that are attached to a third steam roll mounting plate 523 by means of bolts 525 and 530, respectively. The third steam roll mounting plate 523 is attached to a third steam roll adjustment member 521 by a pair of bolts 524 and 531. The third steam roll adjustment member 521 has a pair of flanges and there are two third steam roll adjustment mechanisms 522 and 532 which in conjunction with bolts and nuts operating on the flanges as previously described allow the third steam roll 529 to shift vertically along upper left vertical member 501. There are two third steam plate bearing members 527 with another identical member on the other side of third steam roll 529 which is not shown and serves to hold third steam roll 529 in a rotatable position. There is a third steam roll input 526 to introduce water vapor into third steam roll 529 as well as a third steam roll condensate tube 528 to remove condensed liquid from third steam roll 529.
Pile fabric 8 then travels around the outside perimeter of fourth steam roll 560. Fourth steam roll 560 is rotatably attached to top horizontal support members 551 by means of a pair of bearing members 557. Bearing members 557 are attached to a fourth steam roll mounting plate 554 by means of bolts 556 and 561, respectively. The fourth steam roll mounting plate 554 is attached to a fourth steam roll adjustment member 552 by a pair of bolts 555 and 562. The fourth steam roll adjustment member 552 has a pair of flanges and there are two fourth steam roll adjustment mechanisms 553 and 565 which in conjunction with bolts and nuts operating on the flanges as previously described allow the fourth steam roll 560 to shift horizontally along top horizontal support members 551. There are two fourth steam plate bearing members 557 with another identical member on the other side of fourth steam roll 560 which is not shown and serves to hold fourth steam roll 560 in a rotatable position. There is a fourth steam roll input 558 to introduce water vapor into second steam roll 560 as well as a fourth steam roll condensate tube 559 to remove condensed liquid from fourth steam roll 560.
The pile fabric 8 then travels around fifth steam roll 602 which is the primary steam roll that is used in conjunction with the brushing action. This is rotatably attached by means by a pair of bearing mechanisms 601 which are held by bolts 603 and 604 to horizontal support member 598 which has a left horizontal member 596 and a right horizontal member 597 attached thereto which connect to the underside of top horizontal member 551, respectively. There are a pair of adjustment mechanisms 605 and 606, respectively to be able to shift fifth steam roll 602 horizontally. There is also a fifth steam input 599 and steam condensate tube 600 associated with the fifth primary steam roll 602. There are two brushing mechanisms shown on the left and right of fifth steam roll 602 which are identical, but reversed.
The brushing mechanism on the left has a first housing frame 579 that is connected to a pair of pivot shafts 626 that are rotatably supported in a pair of pivot members 591. Pivot members 591 are attached to adjustment member 595 by means of bolts 592 and 593, respectfully and having an adjustment mechanism 594, as previously described for horizontal movement of the pivot shafts 626 along middle horizontal members 535.
The brushing mechanism on the right has a second housing frame 699 that is connected to a pair of pivot shafts 625 that are rotatably supported in a pair of pivot members 627. Pivot members 627 are attached to adjustment member 610 by means of bolts 628 and 629, respectfully and having an adjustment mechanism 611, as previously described for horizontal movement of the pivot shafts 625 along middle horizontal members 535.
There is a positioning bracket 588 that allows the first housing frame 579 to come back to the exact same position for the same degree of brush penetration. There is an adjustable stop 587 that is connected to the positioning bracket 588 that can be moved toward and away from the face of the positioning bracket 588 to adjust the stop of the first housing frame 579. The adjustable stop 587 will abut an eccentric cam 533 when in position. As shown on the right brushing mechanism, the eccentric cam 533 is mounted on a shaft 622 that is connected to a pulley 621 that is moved by means of an endless belt 620 that is connected to a secondary pulley 619 that is rotated by a hand crank 618 having a pin mechanism to lock the hand crank 618 into position. There is another adjustment mechanism 613 that moves secondary pulley 619 to place tension on endless belt 620. Adjustment mechanism 613 is mounted to the second housing frame 699 by a series of three bolts 614.
There is a motor 580 which drives the system having a pulley 581 and endless belt mechanism 582. This endless belt mechanism 582 drives cylindrical brush 584 by means of attached pulley 1584. Cylindrical brush 584 is rotatably attached to bearing plates 623 that are attached by means of four bolts 590. Endless belt mechanism 582 also drives a cleaning roll 583 with associated pulley 624 the removes lint and debris from the cylindrical brush 584. Cylindrical brush 584 has bristles that can be of any length and only need to contact the fabric between just barely touching the fabric to almost touching the backing of the fabric. The preferred length of bristles is 0.25 to 1.75 inches. It is preferable that these bristles are of stainless steel or of some other non-corrosive material. These bristles also can be coated. The density of the bristles depend on the effect desired and the type of pile fabric brushed. Cleaning roll 583 needs to be able to engage the bristles of cylindrical brush 584. Both cylindrical brushes 584 will engage the fabric that is passed around the outside of the fifth steam roll 602. The preferred r.p.m. of the cylindrical brushes is a range of 500 to 600 with a possible range of 0 to 3000. The pile fabric 8 will preferably pass through this invention at a rate of thirty yards per minute, however, any speed between 0 to 250 yards per minute will work.
Motor 580 is mounted to both frame 579 and 699 by means of bolts 585 and 586 and adjustment mechanism 589. Cleaning roll 583 is mounted in a adjustable bearing assembly plate 616 with a set of four inner bolts 615 and an outer slotted plate assembly 698 with another four bolts with a pair a adjustment mechanisms 578 and 612 attached thereto.
First housing frame 579 is supported by a pin member 577 and there is an air cylinder 576 that is also pivotally mounted by means of pin 575 to a support member 574. There are four bolts 609 attached to a plate which also provides support, as also shown in FIG. 9. Support member 574 is attached to bottom horizontal member 536.
There is a shock absorber shown in FIG. 9 as numeral 670 mounted by means of four bolts 608 to plate member 607 that is attached to middle horizontal member 535. This same structure is replicated on the right hand side with second housing frame 698 supported by a pin member 697 and there is an air cylinder 696 that is also pivotally mounted by means of pin 695 to a support member 694. There are four bolts 693 attached to a plate which also provides support, as also shown in FIG. 9. Support member 694 is attached to bottom horizontal member 536. There is a shock absorber shown in FIG. 9 as numeral 671 mounted by means of four bolts 617 to plate member 616 that is attached to middle horizontal member 535.
All heating and brushing mechanisms to erect pile fabric 8 are mounted on adjustable levelers 537 utilizing dual nut with threaded bolt combination. Air cylinders 176, 376, 576, and 776 have inputs 253, 453, 653 and 853 and outputs 252, 452, 652 and 852, respectively. Air cylinders 296, 496, 696 and 896 have an inputs and 254, 454, 654 and 854 and outputs 255, 455, 655 and 855, respectively.
Pile fabric 8 then goes through lower idler roll 630 which is rotatably supported by pair of bearings 631 which is bolted by means of bolts 632 and 633 to adjustment member 634 having adjustment means 635 and 636 as previously described which attach to the underside of upper middle horizontal support member 538. Pile fabric 8 then exits the third heating and brushing mechanism 500 and enters the fourth brushing and heating mechanism 700 which essentially replicates heating mechanism 500 which for the sake of clarity will be described again.
Referring again specifically to the fourth heating and brushing mechanism generally indicated by numeral 700, as shown in FIG. 4, the pile fabric 8 passes through an upper directing idler roll 705. There is a pair of bearing members 706 rotatably attached to upper directing idler roll 705. Each bearing member 706 are bolted to an adjustment member 702 by means of bolts 704 and 707. There are two adjustment mechanisms 703 and 708 for each bearing member 706, which uses a combination of flanges attached to adjustment member 702 and a threaded bolt with nuts on each side of the flanges attached to the adjustment member 702 to shift upwardly directing idler roll 705 vertically along upper left vertical member 701. Adjustment member 702 is fixedly attached to upper left vertical member 701. The pile fabric 8 then goes around the outside of first steam roll 717. First steam roll 717 is rotatably attached to upper left vertical member 701 by means of a pair of bearing members 715 that are attached to a first steam roll mounting plate 711 by means of bolts 713 and 718, respectively. The first steam roll mounting plate 711 is attached to a first steam roll adjustment member 709 by a pair of bolts 712 and 716. The first steam roll adjustment member 709 has a pair of flanges and there are two first steam roll adjustment mechanisms 710 and 720 which in conjunction with bolts and nuts operating on the flanges as previously described allow the steam roll 717 to shift vertically along upper left vertical member 701. There are two first steam plate bearing members 715 with another identical member on the other side of first steam roll 717 which is not shown and serves to hold first steam roll 717 in a rotatable position. There is a first steam roll input 714 to introduce water vapor into first steam roll 717 as well as a first steam roll condensate tube 716 to remove condensed liquid from first steam roll 717.
Pile fabric 8 then travels around the outside perimeter of second steam roll 747. Second steam roll 747 is rotatably attached to upper middle horizontal support members 738 by means of a pair of bearing members 744. Bearing members 744 are attached to a second steam roll mounting plate 741 by means of bolts 743 and 748, respectively. The second steam roll mounting plate 741 is attached to a second steam roll adjustment member 739 by a pair of bolts 749 and 742. The second steam roll adjustment member 739 has a pair of flanges and there are two first steam roll adjustment mechanisms 740 and 750 which in conjunction with bolts and nuts operating on the flanges as previously described allow the second steam roll 747 to shift horizontally along upper middle horizontal support members 738. There are two second steam plate bearing members 744 with another identical member on the other side of second steam roll 747 which is not shown and serves to hold second steam roll 747 in a rotatable position. There is a second steam roll input 745 to introduce water vapor into second steam roll 747 as well as a second steam roll condensate tube 746 to remove condensed liquid from second steam roll 747.
The pile fabric 8 then goes around the outside of third steam roll 729. Third steam roll 729 is rotatably attached to upper left vertical member 701 by means of a pair of bearing members 727 that are attached to a third steam roll mounting plate 723 by means of bolts 725 and 730, respectively. The third steam roll mounting plate 723 is attached to a third steam roll adjustment member 721 by a pair of bolts 724 and 731. The third steam roll adjustment member 721 has a pair of flanges and there are two third steam roll adjustment mechanisms 722 and 732 which in conjunction with bolts and nuts operating on the flanges as previously described allow the third steam roll 729 to shift vertically along upper left vertical member 701. There are two third steam plate bearing members 727 with another identical member on the other side of third steam roll 729 which is not shown and serves to hold third steam roll 729 in a rotatable position. There is a third steam roll input 726 to introduce water vapor into third steam roll 729 as well as a third steam roll condensate tube 728 to remove condensed liquid from third steam roll 729.
Pile fabric 8 then travels around the outside perimeter of fourth steam roll 760. Fourth steam roll 760 is rotatably attached to top horizontal support members 751 by means of a pair of bearing members 757. Bearing members 757 are attached to a fourth steam roll mounting plate 754 by means of bolts 756 and 761, respectively. The fourth steam roll mounting plate 754 is attached to a fourth steam roll adjustment member 752 by a pair of bolts 755 and 762. The fourth steam roll adjustment member 752 has a pair of flanges and there are two fourth steam roll adjustment mechanisms 753 and 765 which in conjunction with bolts and nuts operating on the flanges as previously described allow the fourth steam roll 760 to shift horizontally along top horizontal support members 751. There are two fourth steam plate bearing members 757 with another identical member on the other side of fourth steam roll 760 which is not shown and serves to hold fourth steam roll 760 in a rotatable position. There is a fourth steam roll input 758 to introduce water vapor into second steam roll 760 as well as a fourth steam roll condensate tube 759 to remove condensed liquid from fourth steam roll 760.
The pile fabric 8 then travels around fifth steam roll 802 which is the primary steam roll that is used in conjunction with the brushing action. This is rotatably attached by means by a pair of bearing mechanisms 801 which are held by bolts 803 and 804 to horizontal support member 798 which has a left horizontal member 796 and a right horizontal member 797 attached thereto which connect to the underside of top horizontal member 751, respectively. There are a pair of adjustment mechanisms 805 and 806, respectively to be able to shift fifth steam roll 802 horizontally. There is also a fifth steam input 799 and steam condensate tube 800 associated with the fifth primary steam roll 802. There are two brushing mechanisms shown on the left and right of fifth steam roll 802 which are identical, but reversed.
The brushing mechanism on the left has a first housing frame 779 that is connected to a pair of pivot shafts 826 that are rotatably supported in a pair of pivot members 791. Pivot members 791 are attached to adjustment member 795 by means of bolts 792 and 793, respectfully and having an adjustment mechanism 794, as previously described for horizontal movement of the pivot shafts 826 along middle horizontal members 735.
The brushing mechanism on the right has a second housing frame 899 that is connected to a pair of pivot shafts 825 that are rotatably supported in a pair of pivot members 827. Pivot members 827 are attached to adjustment member 810 by means of bolts 828 and 829, respectfully and having an adjustment mechanism 811, as previously described for horizontal movement of the pivot shafts 825 along middle horizontal members 735.
There is a positioning bracket 788 that allows the first housing frame 779 to come back to the exact same position for the same degree of brush penetration. There is an adjustable stop 787 that is connected to the positioning bracket 788 that can be moved toward and away from the face of the positioning bracket 788 to adjust the stop of the first housing frame 779. The adjustable stop 787 will abut an eccentric cam 733 when in position. As shown on the right brushing mechanism, the eccentric cam 733 is mounted on a shaft 822 that is connected to a pulley 821 that is moved by means of an endless belt 820 that is connected to a secondary pulley 819 that is rotated by a hand crank 818 having a pin mechanism to lock the hand crank 818 into position. There is another adjustment mechanism 813 that moves secondary pulley 819 to place tension on endless belt 820. Adjustment mechanism 813 is mounted to the second housing frame 899 by a series of three bolts 814.
There is a motor 780 which drives the system having a pulley 781 and endless belt mechanism 782. This endless belt mechanism 782 drives cylindrical brush 784 by means of attached pulley 1784. Cylindrical brush 784 is rotatably attached to bearing plates 823 that are attached by means of four bolts 790. Endless belt mechanism 782 also drives a cleaning roll 783 with associated pulley 824 the removes lint and debris from the cylindrical brush 784. Cylindrical brush 784 has bristles that can be of any length and only need to contact the fabric between just barely touching the fabric to almost touching the backing of the fabric. The preferred length of bristles is 0.25 to 1.75 inches. It is preferable that these bristles are of stainless steel or of some other non-corrosive material. These bristles also can be coated. The density of the bristles depend on the effect desired and the type of pile fabric brushed. Cleaning roll 783 needs to be able to engage the bristles of cylindrical brush 784. Both cylindrical brushes 784 will engage the fabric that is passed around the outside of the fifth steam roll 802. The preferred r.p.m. of the cylindrical brushes is a range of 500 to 600 with a possible range of 0 to 3000. The pile fabric 8 will preferably pass through this invention at a rate of thirty yards per minute, however, any speed between 0 to 250 yards per minute will work.
Motor 780 is mounted to both frame 779 and 899 by means of bolts 785 and 786 and adjustment mechanism 789. Cleaning roll 783 is mounted in a adjustable bearing assembly plate 816 with a set of four inner bolts 815 and an outer slotted plate assembly 898 with another four bolts with a pair a adjustment mechanisms 778 and 812 attached thereto.
First housing frame 779 is supported by a pin member 777 and there is an air cylinder 776 that is also pivotally mounted by means of pin 775 to a support member 774. There are four bolts 809 attached to a plate which also provides support, as also shown in FIG. 9. Support member 774 is attached to bottom horizontal member 736.
There is a shock absorber shown in FIG. 9 as numeral 870 mounted by means of four bolts 808 to plate member 807 that is attached to middle horizontal member 735. This same structure is replicated on the right hand side with second housing frame 898 supported by a pin member 897 and there is an air cylinder 896 that is also pivotally mounted by means of pin 895 to a support member 894. There are four bolts 893 attached to a plate which also provides support, as also shown in FIG. 9. Support member 894 is attached to bottom horizontal member 736. There is a shock absorber shown in FIG. 9 as numeral 871 mounted by means of four bolts 817 to plate member 816 that is attached to middle horizontal member 735.
All heating and brushing mechanisms to erect pile fabric 8 are mounted on adjustable levelers 737 utilizing dual nut with threaded bolt combination. Air cylinders 176, 376, 576, and 776 have inputs 253,453, 653 and 853 and outputs 252, 452, 652 and 852, respectively. Air cylinders 296, 496, 696 and 896 have an inputs and 254, 454, 654 and 854 and outputs 255, 455, 655 and 855, respectively.
Pile fabric 8 then goes through lower idler roll 830 which is rotatably supported by pair of bearings 831 which is bolted by means of bolts 832 and 833 to adjustment member 834 having adjustment means 835 and 836 as previously described which attach to the underside of upper middle horizontal support member 738. Pile fabric 8 then exits the fourth heating and brushing mechanism 700.
All heating and brushing mechanisms to erect pile fabric 8 are mounted on adjustable levelers 737 utilizing dual nut with threaded bolt combination.
Pile fabric 8 then goes through lower idler roll 830 which is rotatably supported by pair of bearings 831 which is bolted by means of bolts 834 and 833 to adjustment member 834 having adjustment means 835 and 836 as previously described which attach to the underside of upper middle horizontal support member 738.
The pile fabric 8 then goes through a first s-wrap roll 911, second s-wrap roll 914, third s-wrap roll 913 and then exit the fourth heating and brushing mechanism 700, as shown in FIG. 5. The s-wrap rolls 911, 914 and 913 are high friction rolls attached to bearing members to apply tension to the pile fabric 8 and are attached a frame member 915 by means of a set of four bolts 914. Frame member 915 is attached to the upper middle horizontal support members 138 by means of and adjustment plate 916 and adjustment mechanism 917, respectively to allow horizontal adjustment of the frame member 915 on the upper middle horizontal support members 138. The pile fabric is then transported to a take-off roll 48 that is rotatably mounted on a shaft and dual bearing assembly 30 that is mounted to a frame member 34 with wheels 34.
Referring now to FIG. 6, there is a main drive motor 958 which rotates steam rolls throughout the system. The main drive motor 958 is attached to a gear reduction mechanism 957 that is attached to sprocket 960. Gear reduction mechanism 957 is attached to frame member 964 that is attached to an L-shaped adjustment member 963 having an adjustment mechanism 964 as previously described. There are a pair of bolts 965 that secure gear reduction mechanism 957 to the L-shaped adjustment member 963.
There is a second sprocket 971 attached to second steam roll 547 and a chain 974 that rotatably interconnects sprocket 960 and second sprocket 971. Fixedly attached to second sprocket 971 is a secondary sprocket 973. Fixedly attached to third steam roll 549 is third sprocket 974 and fixedly attached to fourth steam roll 560 is fourth sprocket 975 and fixedly attached to fifth primary steam roll 604 is fifth sprocket 976. As shown in FIG. 4, there is a sixth sprocket 440 having a dual bearing mechanism 441 mounted on an adjustment plate 444 by two bolts 444, 443 with adjustment mechanisms 445 and 446, as previously described.
There is a seventh sprocket 977 fixedly attached to first steam roll 517 and a eighth sprocket 673 rotatably mounted to the upper right vertical members 565 with an endless chain 978 engaging and driving the seventh sprocket 977 and eighth sprocket 673. Seventh sprocket 977 has a secondary sprocket 980 that rotates therewith and eighth sprocket 673 has a secondary sprocket 674 that fixedly rotates therewith. As shown in FIGS. 4 and 9, there is a pair of bearing members 675 for rotating the combination of sprockets 673 and 674. The pair of bearing members 675 is attached to adjustment plate 678 by means of bolts 676 and 677. There are also adjustment mechanisms 679 and 680, as previously described.
For clarification as shown in FIG. 6, chain 36 engages secondary seventh sprocket 980, then secondary sprocket 973, then third sprocket 974, then fourth sprocket 975, then fifth sprocket 976 and finally sixth sprocket 640 before exiting this particular heating and brushing mechanism 500. The two free ends of chain 36 then engage sixth sprocket 440 of heating and brushing mechanism 300. This drive scheme is replicated throughout all four heating and brushing mechanisms. At the right hand side of FIG. 6, the chain from the fourth heating and brushing mechanism 500 is engaging the eighth secondary sprocket 674.
As shown on FIG. 9, closure 178 and 498 are actually enclosed in which lint is vacuumed out of the system by means of suction to 933, as shown.
FIG. 8 discloses fifth primary steam roll 602 having pile fabric 8 position thereon in contact with the bristles of cylindrical roll 914 for cylindrical brush 584.
It is not intended that the scope of this invention be limited to the specific embodiment illustrated and described. Rather, it is intended that the scope of the invention be defined by the appendant claims and their equivalents. | A method and apparatus for continuous treatment of webs of fabric having upright pile comprised of wetting the fabric to at least 50% saturation, heating the fabric to approximately 225° to 350° Fahrenheit and then brushing the fabric in both the pile and counter-pile directions. The presence of liquid and steam plasticize and lubricate the fibers, thereby allowing an easier, more complete return to the uncrushed state. | 3 |
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