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US2662971A
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Coded track circuit signaling system
Assignee: SPX Technologies Inc
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Filing: 1949-07-15
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Granted: 1953-12-15
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Expires: 1969-07-15
Abstract
No abstract record available.
Inventors
- 👤 James Y Howard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 04:38
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)
US2171771A
Cited
US2291579A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-12-14 | 1957-06-15 | 1957-12-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-12-14 | 1961-06-15 | 1961-12-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-12-14 | 1965-06-15 | 1965-12-15 | $7700.00 | Window Closed / Lapsed |