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US3004149A
Expired / Lapsed
US
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Railway track occupancy detectors
Assignee: Westinghouse Air Brake Co
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Filing: 1959-10-28
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Granted: 1961-10-10
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Expires: 1979-10-28
Abstract
No abstract record available.
Inventors
- 👤 Crawford E Staples
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:25
CPC Classifications
B; B61; B61L; B61L13/00; B61L13/005; B61L23/00; B61L23/08; B61L23/12
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) | 1964-10-09 | 1965-04-10 | 1965-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-10-09 | 1969-04-10 | 1969-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-10-09 | 1973-04-10 | 1973-10-10 | $7700.00 | Window Closed / Lapsed |