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US1670641A
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US
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Mechanically-piloted dirigible device
Assignee: Sperry Gyroscope Co Ltd
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Filing: 1918-04-18
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Granted: 1928-05-22
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Expires: 1938-04-18
Abstract
No abstract record available.
Inventors
- 👤 Lawrence B Sperry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:53
CPC Classifications
F; F42; F42B; F42B17/00
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) | 1931-05-22 | 1931-11-21 | 1932-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1935-05-22 | 1935-11-21 | 1936-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1939-05-22 | 1939-11-21 | 1940-05-22 | $7700.00 | Window Closed / Lapsed |