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Patent US3152647A successfully refreshed from Google Patents.
US3152647A
Expired / Lapsed
US
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Rotor blade control mechanism for rotary wing aircraft
Assignee: Boelkow Entwicklungen KG
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Filing: 1961-09-19
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Granted: 1964-10-13
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Expires: 1981-09-19
Abstract
No abstract record available.
Inventors
- 👤 Derschmidt Hans
- 👤 Eck Gerhard
- 👤 Muller Martin
- 👤 Schekulin Josef
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:48
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/54
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2511687A
Cited
US2418030A
Cited
GB581797A
Cited
US2692650A
Cited
US2658576A
Cited
US2957526A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-10-13 | 1968-04-13 | 1968-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-10-13 | 1972-04-13 | 1972-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-10-13 | 1976-04-13 | 1976-10-13 | $7700.00 | Window Closed / Lapsed |