Patent US2640944A successfully refreshed from Google Patents.
US2640944A
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Electrical contact brush
Assignee: Union Carbide Corp
•
Filing: 1949-06-04
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Granted: 1953-06-02
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Expires: 1969-06-04
Abstract
No abstract record available.
Inventors
- 👤 Ramadanoff Dimiter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 01:26
CPC Classifications
H; H01; H01R; H01R39/00; H01R39/02; H01R39/18; H01R39/20; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9265; Y10S428/929
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
25 words
AN ELECTRICAL CONTACT BRUSH COMPRISING CARBON AND NOT MORE THAN 10 PERCENT BY WEIGHT FINELY DIVIDED SILVER, SAID SILVER BEING DISTRIBUTED UNIFORMLY THROUGHOUT SAID BRUSH.
Claim 2
Dependent Claim
25 words
AN ELECTRICAL CONTACT BRUSH COMPRISING CARBON AND NOT MORE THAN 10 PERCENT BY WEIGHT FINELY DIVIDED SILVER, SAID SILVER BEING DISTRIBUTED UNIFORMLY THROUGHOUT SAID BRUSH.
References Cited (Backward Citations)
US656651A
Cited
US656652A
Cited
AU1703228A
Cited
US1884298A
Cited
US1887559A
Cited
US2411060A
Cited
US2418811A
Cited
US2454448A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-06-01 | 1956-12-01 | 1957-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-06-01 | 1960-12-01 | 1961-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-06-01 | 1964-12-01 | 1965-06-02 | $7700.00 | Window Closed / Lapsed |