US2731552A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cab signalling system for railroads
Assignee: SPX Technologies Inc
•
Filing: 1951-05-19
•
Granted: 1956-01-17
•
Expires: 1971-05-19
Abstract
No abstract record available.
Inventors
- 👤 Hugh C Kendall
- 👤 Frank P Zaffarano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:32
CPC Classifications
B; B61; B61L; B61L3/00; B61L3/16; B61L3/22; B61L3/221
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2503671A
Cited
US1531574A
Cited
US2197416A
Cited
US2200188A
Cited
US2293307A
Cited
US2371568A
Cited
US2312050A
Cited
US2349987A
Cited
US2693525A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-01-16 | 1959-07-18 | 1960-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-01-16 | 1963-07-18 | 1964-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-01-16 | 1967-07-18 | 1968-01-17 | $7700.00 | Window Closed / Lapsed |