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US2427981A
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Drive and pitch control mechanism for helicopter rotors
Assignee: THOMPSON WADE CORP
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Filing: 1944-12-09
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Granted: 1947-09-23
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Expires: 1964-12-09
Abstract
No abstract record available.
Inventors
- 👤 Tom H Thompson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:29
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/54
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-09-22 | 1951-03-24 | 1951-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-09-22 | 1955-03-24 | 1955-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-09-22 | 1959-03-24 | 1959-09-23 | $7700.00 | Window Closed / Lapsed |