Patent USRE31413E successfully refreshed from Google Patents.
USRE31413E
Expired / Lapsed
US
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Gas depolarized electrochemical cells and method of assembly
Assignee: Duracell Inc USA
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Filing: 1980-02-22
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Granted: 1983-10-11
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Expires: 2000-02-22
Abstract
Abstract A button type gas depolarized electrochemical cell that utilizes an air cathode which is sandwiched and sealed by an insulator and a pair of casings that interlock around the insulator to provide a leakproof cell. The invention also includes a process of assembling the cell to form a leakproof cell with a minimal number of parts by compressing the cell so as to cause plastic deformation and consequently a permanently stressed button cell.
Inventors
- 👤 Arthur M. Jaggard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 00:44
CPC Classifications
H; H01; H01M; H01M12/00; H01M12/04; H01M12/06; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49108; Y10T29/4911
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
364 words
A .Iadd.sealed and sized .Iaddend.gas depolarized electrochemical cell comprising: a first metal housing having a closed end and an open end, said closed end having an opening therein to allow gas to enter said first metal housing, said closed end of said first metal housing forming a first external electrical contact for said gas depolarized electrochemical cell, said first metal housing having means for fastening said first metal housing to a second metal housing: a second metal housing having a closed end and an open end, said second metal housing having a region therein for receiving an anode material, said closed end of said second metal housing forming a second external electrical contact for said gas depolarized electrochemical cell; said second metal housing having means for fastening to said first metal housing; a cathode assembly including an electrically conductive current collecting member, said current collecting member forming electrical contact with said first metal housing; a hydrophobic layer on one side of said cathode assembly and a separator on the opposite side of said cathode assembly; a single insulating and sealing member having an L-shaped cross section shape, said insulating and sealing member having a first surface for forming sealing contact with said first metal housing, said insulating and sealing member having a second surface for forming sealing contact with said second metal housing; said insulating member having a third surface for abutting against and extending partially along said cathode assembly to thereby firmly hold said cathode assembly against said metal housing; anode material located in said second metal housing to form electrical contact with said second metal housing, said anode material located adjacent said separator; and an electrolyte in said gas depolarized electrochemical cell so that said second metal housing, said first metal housing, and said insulating and sealing member coact to simultaneously seal and maintain said first metal housing and said second metal housing in a leakproof electrolyte seal.Iadd.; said cell further characterized by a configuration in which said cathode assembly consists of an annular outer portion and a continuous arcuate convexo-concave center portion, said center portion having been dished or deformed in the same direction during sealing and sizing of said cell.Iaddend..
Claim 2
Dependent Claim
364 words
A .Iadd.sealed and sized .Iaddend.gas depolarized electrochemical cell comprising: a first metal housing having a closed end and an open end, said closed end having an opening therein to allow gas to enter said first metal housing, said closed end of said first metal housing forming a first external electrical contact for said gas depolarized electrochemical cell, said first metal housing having means for fastening said first metal housing to a second metal housing: a second metal housing having a closed end and an open end, said second metal housing having a region therein for receiving an anode material, said closed end of said second metal housing forming a second external electrical contact for said gas depolarized electrochemical cell; said second metal housing having means for fastening to said first metal housing; a cathode assembly including an electrically conductive current collecting member, said current collecting member forming electrical contact with said first metal housing; a hydrophobic layer on one side of said cathode assembly and a separator on the opposite side of said cathode assembly; a single insulating and sealing member having an L-shaped cross section shape, said insulating and sealing member having a first surface for forming sealing contact with said first metal housing, said insulating and sealing member having a second surface for forming sealing contact with said second metal housing; said insulating member having a third surface for abutting against and extending partially along said cathode assembly to thereby firmly hold said cathode assembly against said metal housing; anode material located in said second metal housing to form electrical contact with said second metal housing, said anode material located adjacent said separator; and an electrolyte in said gas depolarized electrochemical cell so that said second metal housing, said first metal housing, and said insulating and sealing member coact to simultaneously seal and maintain said first metal housing and said second metal housing in a leakproof electrolyte seal.Iadd.; said cell further characterized by a configuration in which said cathode assembly consists of an annular outer portion and a continuous arcuate convexo-concave center portion, said center portion having been dished or deformed in the same direction during sealing and sizing of said cell.Iaddend..
Claim 3
Dependent Claim
12 words
The invention of claim 1 wherein said cell is circular in shape.
Claim 4
Dependent Claim
21 words
The invention of claim 1 wherein said second metal housing has a beveled bottom for mating with said first metal housing.
Claim 5
Dependent Claim
14 words
The invention of claim 1 wherein said first metal housing has a crown thereon.
Claim 6
Dependent Claim
13 words
The invention of claim 1 including a blotter located on said cathode assembly.
Claim 7
Dependent Claim
23 words
The invention of claim 1 wherein said one of said metal housings is partially embedded in said insulator to produce an electrolyte seal.
Claim 8
Dependent Claim
16 words
The invention of claim 1 wherein there are at least two electrolyte sealing areas in series.
Claim 9
Dependent Claim
19 words
The invention of claim 1 wherein said first metal housing is deformed radially inward on said second metal housing.
Claim 10
Dependent Claim
20 words
The invention of claim 1 wherein said insulator sealing member projects past the open end of said first metal housing.
Claim 11
Dependent Claim
12 words
The invention of claim 1 wherein the first metal housing is steel.
Claim 12
Dependent Claim
25 words
The invention of claim 1 wherein said insulating member and said cathode subassembly are in pressure contact against a portion of said first metal housing.
Claim 13
Dependent Claim
167 words
A .Iadd.sealed and sized .Iaddend.gas depolarized electrochemical button cell comprising five main components including: an anode cup having a surface for shapingly engaging a cathode cup and for holding anode material and forming an external anode contact; anode material located in said anode cup; a cathode cup .Iadd.containing a gas inlet passage and .Iaddend.having a surface for shapingly engaging said anode cup and for holding a cathode assembly and forming an external cathode contact; a cathode assembly located in said cathode cup; and a single insulator and sealing member having an L-shaped cross section shape held in compression between said surface of said anode cup and said surface of said cathode cup to thereby produce a leakproof electrochemical button cell.Iadd.; and said cell is further characterized by a configuration in which said cathode assembly consists of an annular outer portion and a continuous arcuate convexo-concave center portion, said center portion having been dished or deformed in the same direction during the sealing and sizing of said cell.Iaddend..
Claim 14
Dependent Claim
167 words
A .Iadd.sealed and sized .Iaddend.gas depolarized electrochemical button cell comprising five main components including: an anode cup having a surface for shapingly engaging a cathode cup and for holding anode material and forming an external anode contact; anode material located in said anode cup; a cathode cup .Iadd.containing a gas inlet passage and .Iaddend.having a surface for shapingly engaging said anode cup and for holding a cathode assembly and forming an external cathode contact; a cathode assembly located in said cathode cup; and a single insulator and sealing member having an L-shaped cross section shape held in compression between said surface of said anode cup and said surface of said cathode cup to thereby produce a leakproof electrochemical button cell.Iadd.; and said cell is further characterized by a configuration in which said cathode assembly consists of an annular outer portion and a continuous arcuate convexo-concave center portion, said center portion having been dished or deformed in the same direction during the sealing and sizing of said cell.Iaddend..
Claim 15
Dependent Claim
22 words
The invention of claim 12 wherein said insulating member, said anode cup and said cathode cup coact to produce electrolyte sealing regions.
Claim 16
Dependent Claim
25 words
The invention of claim 13 wherein there are at least two electrolyte sealing regions in series between said anode cup and said insulating sealing member.
Claim 17
Dependent Claim
25 words
The invention of claim 14 wherein there are at least two electrolyte sealing regions in series between said cathode cup and said insulating sealing member.
Claim 18
Dependent Claim
19 words
The invention of claim 15 wherein said anode cup has a beveled corner for mating with said cathode cup.
Claim 19
Dependent Claim
13 words
The invention of claim 16 wherein said cathode cup has a crown portion.
Claim 20
Dependent Claim
13 words
The invention of claim 17 wherein said crown contains a gas inlet passage.
Claim 21
Dependent Claim
13 words
The invention of claim 18 including a blotter located adjacent said cathode assembly.
Claim 22
Independent Claim
225 words
The method of assemblying a .Iadd.sealed and sized .Iaddend.gas depolarized electrochemical cell comprising the steps of: forming a first electrode cup having means for engaging a second electrode cup; forming a second electrode cup having a top edge and means for engaging said first electrode cup and nestable in said first electrode cup; inserting .[.an electrode.]. .Iadd.a cathode .Iaddend.assembly in one of said first electrode cup and said second electrode cup; placing anode material in one of said first electrode cup and second electrode cup; placing an insulating and sealing member having an L-shaped cross section shape on said second electrode cup so a portion of said insulating and sealing member engages said top edge of said second electrode cup; and nesting said second electrode cup and said insulating and sealing member in said first electrode cup followed by deforming said first electrode cup and said insulating and sealing member until said first electrode cup and said insulating and sealing member shapingly engage said means on said second electrode cup with said insulating and sealing member therebetween.Iadd.; and wherein said cell is further characterized by a configuration in which said cathode assembly consists of an annular outer portion and a continuous arcuate convexo-concave center portion, said center portion having been dished or deformed in the same direction during said deforming of said first electrode cup.Iaddend..
Claim 23
Independent Claim
225 words
The method of assemblying a .Iadd.sealed and sized .Iaddend.gas depolarized electrochemical cell comprising the steps of: forming a first electrode cup having means for engaging a second electrode cup; forming a second electrode cup having a top edge and means for engaging said first electrode cup and nestable in said first electrode cup; inserting .[.an electrode.]. .Iadd.a cathode .Iaddend.assembly in one of said first electrode cup and said second electrode cup; placing anode material in one of said first electrode cup and second electrode cup; placing an insulating and sealing member having an L-shaped cross section shape on said second electrode cup so a portion of said insulating and sealing member engages said top edge of said second electrode cup; and nesting said second electrode cup and said insulating and sealing member in said first electrode cup followed by deforming said first electrode cup and said insulating and sealing member until said first electrode cup and said insulating and sealing member shapingly engage said means on said second electrode cup with said insulating and sealing member therebetween.Iadd.; and wherein said cell is further characterized by a configuration in which said cathode assembly consists of an annular outer portion and a continuous arcuate convexo-concave center portion, said center portion having been dished or deformed in the same direction during said deforming of said first electrode cup.Iaddend..
Claim 24
Dependent Claim
25 words
The process of claim 20 including the step of radially deforming said first electrode cup until a permanent deformation of said first electrode cup occurs.
Claim 25
Dependent Claim
27 words
The process of claim 21 including the step of forming a crown in at least one of said first electrode cup .[.on.]. .Iadd.and .Iaddend.said second electrode cup.
Claim 26
Dependent Claim
42 words
The process of claim 22 including the step of bending said means on said first electrode cup until said means on said first electrode cup holds said insulating and sealing member in pressure engagement against said means on said second electrode cup.
Claim 27
Dependent Claim
915 words
The process of claim 23 including the step of axially and radially compressing said first electrode cup on said second electrode cup. .Iadd. 25. A sealed and sized gas depolarized electrochemical cell comprising: a first metal housing having a closed end and an open end, said closed end having an opening therein to allow gas to enter said first metal housing, said closed end of said first metal housing forming a first external electrical contact for said gas depolarized electrochemical cell, said first metal housing having means for fastening said first metal housing to a second metal housing; a second metal housing having a closed end and an open end, said second metal housing having a region therein for receiving an anode material, said closed end of said second metal housing forming a second external electrical contact for said gas depolarized electrochemical cell; said second metal housing having means for fastening to said first metal housing; a cathode assembly including an electrically conductive current collecting member, said current collecting member forming electrical contact with said first metal housing; a hydrophobic layer on one side of said cathode assembly and a separator on the opposite side of said cathode assembly; a single insulating and sealing member having an L-shaped cross section shape, said insulating and sealing member having a first surface for forming sealing contact with said first metal housing, said insulating and sealing member having a second surface for forming sealing contact with said second metal housing; said insulating member having a third surface for abutting against and extending partially along said cathode assembly to thereby firmly hold said cathode assembly against said metal housing; anode material located in said second metal housing to form electrical contact with said second metal housing, said anode material located adjacent said separator; and an electrolyte in said gas depolarized electrochemical cell so that said second metal housing, said first metal housing, and said insulating and sealing member coact to simultaneously seal and maintain said first metal housing and said second metal housing in a leakproof electrolyte seal; and said first metal housing is further characterized by the closed end thereof consisting of an annular flat outer portion and a continuous, arcuate convexo-concave crown center portion with the concave side of said crown center portion facing in the direction of said cathode assembly. .Iaddend. .Iadd. 26. The invention of claim 25 wherein said second metal housing has a beveled bottom for mating with said first metal housing. .Iaddend..Iadd. 27. The invention of claim 25 including a blotter located on said cathode assembly. .Iaddend..Iadd. 28. The invention of claim 25 wherein said first metal housing is deformed radially inward on said second metal housing. .Iaddend. .Iadd. 29. The invention of claim 25 wherein said insulator sealing member projects past the open end of said first metal housing. .Iaddend. .Iadd. 30. A sealed and sized gas depolarized electrochemical cell comprising five main components including: an anode cup having a surface for shapingly engaging a cathode cup and for holding anode material and forming an external anode contact; anode material located in said anode cup; a cathode cup having a closed end and an open end, containing a gas inlet passage and having a surface for shapingly engaging said anode cup and for holding a cathode assembly and forming an external cathode contact; a cathode assembly located in said cathode cup; and a single insulator and sealing member having an L-shaped cross section shape held in compression between said surface of said anode cup and said surface of said cathode cup to thereby produce a leakproof electrochemical button cell; and said cathode cup is further characterized by the closed end thereof consisting of an annular outer portion and a continuous, arcuate convexo-concave crown center portion with the concave side of said crown center portion facing in the direction of said cathode assembly. .Iaddend. .Iadd. 31. The invention of claim 30 wherein said anode cup has a beveled corner for mating with said cathode cup. .Iaddend..Iadd. 32. The invention of claim 31 including a blotter located adjacent said cathode assembly. .Iaddend. .Iadd. 33. The method of assemblying a sealed and sized gas depolarized electrochemical cell comprising the steps of forming a first electrode cup having a closed end and an open end and having means for engaging a second electrode cup; forming a second electrode cup having a top edge and means for engaging said first electrode cup and nestable in said first electrode cup; inserting a cathode assembly in one of said first electrode cup and said second electrode cup; placing anode material in one of said first electrode cup and second electrode cup; placing an insulating and sealing member having an L-shaped cross section shape on said second electrode cup so a portion of said insulating and sealing member engages said top edge of said second electrode cup; and nesting said second electrode cup and said insulating and sealing member in said first electrode cup followed by deforming said first electrode cup and said insulating and sealing member until said first electrode cup and said insulating and sealing member shapingly engage said means on said second electrode cup with said insulating and sealing member therebetween; and wherein said first electrode cup is further characterized by the closed end thereof consisting of an annular outer portion and a continuous, arcuate convexo-concave crown center portion with the concave side of said crown center portion facing in the direction of said cathode assembly. .Iaddend.
Claim 28
Dependent Claim
642 words
.Iadd. 34. The process of claim 33 including the step of radially deforming said first electrode cup until a permanent deformation of said first electrode cup occurs. .Iaddend. .Iadd. 35. A sealed and sized gas depolarized electrochemical cell comprising: a first metal housing having a closed end and an open end, said closed end having an opening therein to allow gas to enter said first metal housing, said closed end of said first metal housing forming a first external electrical contact for said gas depolarized electrochemical cell, said first metal housing having means for fastening said first metal housing to a second metal housing; a second metal housing having a closed end and an open end, said second metal housing having a region therein for receiving an anode material, said closed end of said second metal housing forming a second external electrical contact for said gas depolarized electrochemical cell; said second metal housing having means for fastening to said first metal housing; a cathode assembly including an electrically conductive current collecting member, said current collecting member forming electrical contact with said first metal housing; a hydrophobic layer on one side of said cathode assembly and a separator on the opposite side of said cathode assembly; a single insulating and sealing member having an L-shaped cross section shape, said insulating and sealing member having a first surface for forming sealing contact with said first metal housing, said insulating and sealing member having a second surface for forming sealing contact with said second metal housing; said insulating member having a third surface for abutting against and extending partially along said cathode assembly to thereby firmly hold said cathode assembly against said metal housing; anode material located in said second metal housing to form electrical contact with said second metal housing, said anode material located adjacent said separator; and an electrolyte in said gas depolarized electrochemical cell so that said second metal housing, said first metal housing, and said insulating and sealing member coact to simultaneously seal and maintain said first metal housing and said second metal housing in a leakproof electrolyte seal; and said cathode assembly is further characterized by consisting of an annular outer portion and a continuous, arcuate convexo-concave center portion with the concave side of said center portion facing in the direction of said anode material. .Iaddend. .Iadd. 36. The invention of claim 35 wherein said second metal housing has a beveled bottom for mating with said first metal housing. .Iaddend..Iadd. 37. The invention of claim 35 wherein said first metal housing has a crown thereon. .Iaddend..Iadd. 38. The invention of claim 35 including a blotter located on said cathode assembly. .Iaddend..Iadd. 39. The invention of claim 35 wherein said first metal housing is deformed radially inward on said second metal housing. .Iaddend..Iadd. 40. The invention of claim 35 wherein said insulator sealing member projects past the open end of said first metal housing. .Iaddend. .Iadd. 41. A sealed and sized gas depolarized electrochemical button cell comprising five main components including: an anode cup having a surface for shapingly engaging a cathode cup and for holding anode material and forming an external anode contact; anode material located in said anode cup; a cathode cup containing a gas inlet passage and having a surface for shapingly engaging said anode cup and for holding a cathode assembly and forming an external cathode contact; a cathode assembly located in said cathode cup; and a single insulator and sealing member having an L-shaped cross section shape held in compression between said surface of said anode cup and said surface of said cathode cup to thereby produce a leakproof electrochemical button cell; and said cathode assembly is further characterized by consisting of an annular outer portion and a continuous, arcuate convexo-concave center portion with the concave side of said center portion facing in the direction of
Claim 29
Dependent Claim
301 words
said anode material. .Iaddend. .Iadd. 42. The invention of claim 41 wherein said anode cup has a beveled corner for mating with said cathode cup. .Iaddend..Iadd. 43. The invention of claim 42 wherein said cathode cup has a crown portion. .Iaddend..Iadd. 44. The invention of claim 43 including a blotter located adjacent said cathode assembly. .Iaddend. .Iadd. 45. The method of assembling a sealed and sized gas depolarized electrochemical cell comprising the steps of forming a first electrode cup having means for engaging a second electrode cup; forming a second electrode cup having a top edge and means for engaging said first electrode cup and nestable in said first electrode cup; inserting a cathode assembly in one of said first electrode cup and said second electrode cup; placing anode material in one of said first electrode cup and second electrode cup; placing an insulating and sealing member having an L-shaped cross section shape on said second electrode cup so a portion of said insulating and sealing member engages said top edge of said second electrode cup; placing an insulating and sealing member having an L-shaped cross section shape on said second electrode cup so a portion of said insulating and sealing member engages said top edge of said second electrode cup; nesting said second electrode cup and said insulating and sealing member in said first electrode cup followed by deforming said first electrode cup and said insulating and sealing member until said first electrode cup and said insulating and sealing member shapingly engage said means on said second electrode cup with said insulating and sealing member therebetween; and said cathode assembly is further characterized by consisting of an annular outer portion and a continuous, arcuate convexo-concave center portion with the concave side of said center portion facing in the direction of
Claim 30
Dependent Claim
992 words
said anode material. .Iaddend. .Iadd. 46. The process of claim 45 including the step of radially deforming said first electrode cup until a permanent deformation of said first electrode cup occurs. .Iaddend. .Iadd. 47. A sealed and sized gas depolarized electrochemical cell comprising: a first metal housing having a closed end and an open end, said closed end having an opening therein to allow gas to enter said first metal housing, said closed end of said first metal housing forming a first external electrical contact for said gas depolarized electrochemical cell, said first metal housing having means for fastening said first metal housing to a second metal housing; a second metal housing having a closed end and an open end, said second metal housing having a region therein for receiving an anode material, said closed end of said second metal housing forming a second external electrical contact for said gas depolarized electrochemical cell; said second metal housing having means for fastening to said first metal housing; a cathode assembly including an electrically conductive current collecting member, said current collecting member forming electrical contact with said first metal housing; a hydrophobic layer on one side of said cathode assembly and a separator on the opposite side of said cathode assembly; a single insulating and sealing member having an L-shaped cross section shape, said insulating and sealing member having a first surface for forming sealing contact with said first metal housing, said insulating and sealing member having a second surface for forming sealing contact with said second metal housing; said insulating member having a third surface for abutting against and extending partially along said cathode assembly to thereby firmly hold said cathode assembly against said metal housing; anode material located in said second metal housing to form electrical contact with said second metal housing, said anode material located adjacent said separator; and an electrolyte in said gas depolarized electrochemical cell so that said second metal housing, said first metal housing, and said insulating and sealing member coact to simultaneously seal and maintain said first metal housing and said second metal housing in a leakproof electrolyte seal; and said closed end of said first metal housing is further characterized by consisting of an annular outer portion and a continuous, arcuate convexo-concave center portion, said center portion having been dished or deformed in the same direction during the sealing and sizing of said cell. .Iaddend. .Iadd. 48. The invention of claim 47 wherein said second metal housing has a beveled bottom for mating with said first metal housing. .Iaddend..Iadd. 49. The invention of claim 47 wherein said first metal housing has a crown thereon. .Iaddend..Iadd. 50. The invention of claim 47 including a blotter located on said cathode assembly. .Iaddend..Iadd. 51. The invention of claim 47 wherein said first metal housing is deformed radially inward on said second metal housing. .Iaddend. .Iadd. 52. The invention of claim 47 wherein said insulator sealing member projects past the open end of said first metal housing. .Iaddend. .Iadd. 53. A sealed and sized gas depolarized electrochemical button cell comprising five main components including: an anode cup having a surface for shapingly engaging a cathode cup and for holding anode material and forming an external anode contact; anode material located in said anode cup; a cathode cup having a closed end and an open end, containing a gas inlet passage in said closed end and having a surface for shapingly engaging said anode cup and for holding a cathode assembly and forming an external cathode contact; a cathode assembly located in said cathode cup; and a single insulator and sealing member having an L-shaped cross section shape held in compression between said surface of said anode cup and said surface of said cathode cup to thereby produce a leakproof electrochemical button cell; and said cathode cup is further characterized by the closed end thereof consisting of an annular outer portion and a continuous, arcuate convexo-concave center portion, said center portion having been dished or deformed in the same direction during the sealing and sizing of said cell. .Iaddend. .Iadd. 54. The invention of claim 53 wherein said anode cup has a beveled corner for mating with said cathode cup. .Iaddend. .Iadd. 55. The invention of claim 54 wherein said cathode cup has a crown portion. .Iaddend..Iadd. 56. The invention of claim 55 including a blotter located adjacent said cathode assembly. .Iaddend. .Iadd. 57. The method of assemblying a sealed and sized gas depolarized electrochemical cell comprising the steps of forming a first electrode cup having an open end and a closed end and having means for engaging a second electrode cup; forming a second electrode cup having a top edge and means for engaging said first electrode cup and nestable in said first electrode cup; inserting a cathode assembly in one of said first electrode cup and said second electrode cup; placing anode material in one of said first electrode cup and second electrode cup; placing an insulating and sealing member having an L-shaped cross section shape on said second electrode cup so a portion of said insulating and sealing member engages said top edge of said second electrode cup; nesting said second electrode cup and said insulating and sealing member in said first electrode cup followed by deforming said first electrode cup and said insulating and sealing member until said first electrode cup and said insulating and sealing member shapingly engage said means on said second electrode cup with said insulating and sealing member therebetween; and said closed end of said first electrode cup is further characterized by consisting of an outer annular portion and a continuous, arcuate convexo-concave center portion, said center portion having been dished or deformed in the same direction during the sealing and sizing of said cell. .Iaddend. .Iadd. 58. The process of claim 57 including the step of radially deforming said first electrode cup until a permanent deformation of said first electrode cup occurs.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-10-10 | 1987-04-11 | 1987-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-10 | 1991-04-11 | 1991-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-10 | 1995-04-11 | 1995-10-11 | $7700.00 | Window Closed / Lapsed |