Patent US2841757A successfully refreshed from Google Patents.
US2841757A
Expired / Lapsed
US
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Electrical regulator
Assignee: Westinghouse Air Brake Co
•
Filing: 1956-01-24
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Granted: 1958-07-01
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Expires: 1976-01-24
Abstract
No abstract record available.
Inventors
- 👤 Charles B Shields
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:57
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F1/00; G05F1/10; G05F1/46; G05F1/56; G05F3/22; G05F3/222; G05F3/227
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2268790A
Cited
US2535355A
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US2575107A
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US2693568A
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US2690535A
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US2698416A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-06-30 | 1961-12-30 | 1962-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-06-30 | 1965-12-30 | 1966-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-06-30 | 1969-12-30 | 1970-07-01 | $7700.00 | Window Closed / Lapsed |