Patent US4579611A successfully refreshed from Google Patents.
US4579611A
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Graphite tamped brush connection and method of making same
Assignee: NATIONAL ELECTRICAL CARBON Corp
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Filing: 1983-12-19
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Granted: 1986-04-01
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Expires: 2003-12-19
Abstract
Abstract A connection between a graphite or carbon block having a cavity therein and the end of an electrical conductor disposed therein is made with a tamping material comprising flowable graphite powder, a metal oxide, a resin binder, and a flow promoter such a silica or a resin. The finished connection is treated with an acid dopant which reacts with the metal oxide to form a bond between the conductor and the block.
Inventors
- 👤 Floyd J. Broady
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:25
CPC Classifications
H; H01; H01R; H01R39/00; H01R39/02; H01R39/36; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49119; Y10T428/00; Y10T428/30
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
86 words
A method for connecting an electrical conductor to a carbon block having a cavity, the diameter of said cavity being greater than the diameter of said conductor, comprising blending a resin, silica, graphite, and a metal oxide with a liquid; drying and milling the mixture to a Tyler mesh size of -35 to +600; inserting an end of said conductor into said cavity; tamping the dried milled mixture around the conductor in the cavity; and doping the mixture with an acid solution to cure the assembly.
Claim 2
Independent Claim
86 words
A method for connecting an electrical conductor to a carbon block having a cavity, the diameter of said cavity being greater than the diameter of said conductor, comprising blending a resin, silica, graphite, and a metal oxide with a liquid; drying and milling the mixture to a Tyler mesh size of -35 to +600; inserting an end of said conductor into said cavity; tamping the dried milled mixture around the conductor in the cavity; and doping the mixture with an acid solution to cure the assembly.
Claim 3
Dependent Claim
24 words
The method of claim 1 which includes the step of testing the flowability of said mixture before the mixture is tamped into said cavity.
Claim 4
Dependent Claim
29 words
The method of claim 1 wherein said metal oxide is selected from the group consisting of cupric oxide, siliver oxide, tin oxide, cadmium oxide, lead oxide, and nickel oxide.
Claim 5
Dependent Claim
13 words
The method of claim 1 wherein said acid solution contains a wetting agent.
Claim 6
Dependent Claim
15 words
The method of claim 1 wherein said acid solution contains acetic acid and phosphoric acid.
Claim 7
Dependent Claim
12 words
The method of claim 1 wherein said acid solution contains citric acid.
Claim 8
Dependent Claim
24 words
A tamping composition for securing electrical connections comprising a dry mixture of finely divided particles of graphite, silica, a metal oxide, and a resin.
Claim 9
Dependent Claim
24 words
A tamping composition for securing electrical connections comprising a dry mixture of finely divided particles of graphite, silica, a metal oxide, and a resin.
Claim 10
Dependent Claim
29 words
The composition of claim 7 wherein said metal oxide is selected from the group consisting of cupric oxide, siliver oxide, tin oxide, cadmium oxide, lead oxide, and nickel oxide.
Claim 11
Dependent Claim
17 words
The composition of claim 7 wherein said graphite has a Tyler mesh size of -48 to +325.
Claim 12
Dependent Claim
29 words
The composition of claim 7, 8, or 9 wherein said mixture has a Tyler mesh size of -35 to +600 and a density of from 0.80 to 1.15 g/cc.
Claim 13
Dependent Claim
54 words
A tamping composition for securing electrical connections comprising a dry mixture of finely divided particles of graphite, silica, cupric oxide, and a resin, said graphite having a Tyler mesh size of -48 to +325, said mixture having a Tyler mesh size of -35 to +600 and a density of from 0.80 to 1.15 g/cc.
Claim 14
Dependent Claim
54 words
A tamping composition for securing electrical connections comprising a dry mixture of finely divided particles of graphite, silica, cupric oxide, and a resin, said graphite having a Tyler mesh size of -48 to +325, said mixture having a Tyler mesh size of -35 to +600 and a density of from 0.80 to 1.15 g/cc.
Claim 15
Dependent Claim
19 words
The composition of claim 11 wherein said graphite and said cupric oxide are present in equal amounts by weight.
Claim 16
Dependent Claim
33 words
A tamping composition for securing electrical connections comprising a finely divided mixture of, by weight, 20 parts -48 Tyler mesh graphite, 20 parts cupric oxide, 1 part urea resin, and 0.2 parts silica.
Claim 17
Dependent Claim
33 words
A tamping composition for securing electrical connections comprising a finely divided mixture of, by weight, 20 parts -48 Tyler mesh graphite, 20 parts cupric oxide, 1 part urea resin, and 0.2 parts silica.
Claim 18
Dependent Claim
39 words
In combination, a carbon block having a cavity therein; an electrical conductor having an end portion disposed in said cavity, said conductor being secured therein by the composition of claim 7, 8, 11 or 13 and an acid dopant.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-03-31 | 1989-09-30 | 1990-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-31 | 1993-09-30 | 1994-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-31 | 1997-09-30 | 1998-04-01 | $7700.00 | Window Closed / Lapsed |