US2884516A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Phase sensitive alternating current track circuit
Assignee: Westinghouse Air Brake Co
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Filing: 1956-09-21
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Granted: 1959-04-28
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Expires: 1976-09-21
Abstract
No abstract record available.
Inventors
- 👤 Crawford E Staples
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:19
CPC Classifications
B; B61; B61L; B61L23/00; B61L23/08; B61L23/14; B61L23/16; B61L23/168
Claims Analysis
Total Claims: 0
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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) | 1962-04-27 | 1962-10-27 | 1963-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-04-27 | 1966-10-27 | 1967-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-04-27 | 1970-10-27 | 1971-04-28 | $7700.00 | Window Closed / Lapsed |