Patent US2693241A successfully refreshed from Google Patents.
US2693241A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low drag rotor blade for helicopters
Assignee: Individual
•
Filing: 1946-01-16
•
Granted: 1954-11-02
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Expires: 1966-01-16
Abstract
No abstract record available.
Inventors
- 👤 Charles W Ranson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:24
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/32; B64C27/46
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-11-01 | 1958-05-03 | 1958-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-11-01 | 1962-05-03 | 1962-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-11-01 | 1966-05-03 | 1966-11-02 | $7700.00 | Window Closed / Lapsed |