US2740890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Switching and control means for carrier current transmitters
Assignee: Westinghouse Air Brake Co
•
Filing: 1951-10-25
•
Granted: 1956-04-03
•
Expires: 1971-10-25
Abstract
No abstract record available.
Inventors
- 👤 Lawrence R Golladay
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:05
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/38; H04B1/40; H04B1/44
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1592934A
Cited
US2313071A
Cited
US1955095A
Cited
US2355606A
Cited
US2435262A
Cited
US2579590A
Cited
US2617036A
Cited
US2632086A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-04-03 | 1959-10-03 | 1960-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-04-03 | 1963-10-03 | 1964-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-04-03 | 1967-10-03 | 1968-04-03 | $7700.00 | Window Closed / Lapsed |