US2638990A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aircraft sustaining rotor blade with airflow control
Assignee: Autogiro Company of America
•
Filing: 1947-04-01
•
Granted: 1953-05-19
•
Expires: 1967-04-01
Abstract
No abstract record available.
Inventors
- 👤 Harold F Pitcairn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:57
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/32; B64C27/325; Y; Y10; Y10S; Y10S415/00; Y10S415/914
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
DE86738C
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FR807110A
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GB497048A
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US2412908A
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US2443936A
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US2464651A
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US2464726A
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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) | 1956-05-18 | 1956-11-17 | 1957-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-18 | 1960-11-17 | 1961-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-18 | 1964-11-17 | 1965-05-19 | $7700.00 | Window Closed / Lapsed |