US2581320A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multiengine contra-rotating propeller drive transmission
Assignee: Douglas Aircraft Co Inc
•
Filing: 1945-07-20
•
Granted: 1952-01-01
•
Expires: 1965-07-20
Abstract
No abstract record available.
Inventors
- 👤 Edward F Burton
- 👤 Jr Charles S Glasgow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:58
CPC Classifications
F; F16; F16H; F16H37/00; F16H37/02; F16H37/06; F16H37/08; F16H37/0806; B; B64; B64D; B64D35/00; B64D35/04; B64D35/06; B64D35/08; F16H2700/00; F16H2700/02
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
USRE15550E
Cited
US1019283A
Cited
US1540610A
Cited
US1456008A
Cited
US1696836A
Cited
US1747334A
Cited
US1969993A
Cited
US1899490A
Cited
US2042168A
Cited
US1971846A
Cited
US2140324A
Cited
US2297214A
Cited
US2152552A
Cited
US2396745A
Cited
US2310220A
Cited
US2312624A
Cited
US2389778A
Cited
US2380889A
Cited
US2456485A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-12-31 | 1955-07-02 | 1956-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-12-31 | 1959-07-02 | 1960-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-12-31 | 1963-07-02 | 1964-01-01 | $7700.00 | Window Closed / Lapsed |