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US2573016A
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US
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Helicopter rotor control
Assignee: Individual
•
Filing: 1945-12-10
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Granted: 1951-10-30
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Expires: 1965-12-10
Abstract
No abstract record available.
Inventors
- 👤 Harold D Harby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:57
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/54; B64C27/58; B64C27/59; B64C27/615; B64C27/04; B64C27/06; Y; Y02; Y02T; Y02T50/00; Y02T50/30
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) | 1954-10-29 | 1955-04-30 | 1955-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-10-29 | 1959-04-30 | 1959-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-10-29 | 1963-04-30 | 1963-10-30 | $7700.00 | Window Closed / Lapsed |