US2669313A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Helicopter rotor
Assignee: RTX Corp
•
Filing: 1947-01-18
•
Granted: 1954-02-16
•
Expires: 1967-01-18
Abstract
No abstract record available.
Inventors
- 👤 Ralph B Lightfoot
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:02
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/54; B64C27/58; B64C27/59; Y; Y10; Y10S; Y10S416/00; Y10S416/02
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1949785A
Cited
US1950411A
Cited
US2021470A
Cited
US1990291A
Cited
US1999136A
Cited
US2070657A
Cited
US2135700A
Cited
US2265366A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-02-15 | 1957-08-17 | 1958-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-02-15 | 1961-08-17 | 1962-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-02-15 | 1965-08-17 | 1966-02-16 | $7700.00 | Window Closed / Lapsed |