Patent US2461791A successfully refreshed from Google Patents.
US2461791A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable pitch airscrew
Assignee: De Havilland Aircraft Co Ltd
•
Filing: 1943-08-02
•
Granted: 1949-02-15
•
Expires: 1963-08-02
Abstract
No abstract record available.
Inventors
- 👤 Warde Robert Henry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:22
CPC Classifications
B; B64; B64C; B64C11/00; B64C11/30; B64C11/38; B64C11/42
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2204640A
Cited
US2154887A
Cited
US2216416A
Cited
US2174717A
Cited
GB483824A
Cited
US2243852A
Cited
GB517696A
Cited
US2264089A
Cited
GB541839A
Cited
US2338483A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-02-15 | 1952-08-16 | 1953-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-02-15 | 1956-08-16 | 1957-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-02-15 | 1960-08-16 | 1961-02-15 | $7700.00 | Window Closed / Lapsed |