US2549407A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Helicopter rotor construction
Assignee: Individual
•
Filing: 1948-06-02
•
Granted: 1951-04-17
•
Expires: 1968-06-02
Abstract
No abstract record available.
Inventors
- 👤 Apostolescu Stefan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:42
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/006; B64C27/04; B64C27/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2389798A
Cited
US2384445A
Cited
US2427936A
Cited
US2394846A
Cited
US2437165A
Cited
US2448073A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-04-16 | 1954-10-16 | 1955-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-04-16 | 1958-10-16 | 1959-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-04-16 | 1962-10-16 | 1963-04-17 | $7700.00 | Window Closed / Lapsed |