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US2293801A
Expired / Lapsed
US
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Hollow metal propeller blade
Assignee: RTX Corp
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Filing: 1938-10-01
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Granted: 1942-08-25
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Expires: 1958-10-01
Abstract
No abstract record available.
Inventors
- 👤 Frank W Caldwell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:55
CPC Classifications
B; B64; B64C; B64C11/00; B64C11/16; B64C11/20; B64C11/24; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49316; Y10T29/49332; Y10T29/49334
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1945-08-24 | 1946-02-23 | 1946-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1949-08-24 | 1950-02-23 | 1950-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1953-08-24 | 1954-02-23 | 1954-08-25 | $7700.00 | Window Closed / Lapsed |