US2657741A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air control ring
Assignee: Individual
•
Filing: 1948-07-06
•
Granted: 1953-11-03
•
Expires: 1968-07-06
Abstract
No abstract record available.
Inventors
- 👤 Ralph C Brierly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:46
CPC Classifications
F; F23; F23C; F23C7/00; F23C7/002; Y; Y10; Y10T; Y10T137/00; Y10T137/9682
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) | 1956-11-02 | 1957-05-04 | 1957-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-11-02 | 1961-05-04 | 1961-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-11-02 | 1965-05-04 | 1965-11-03 | $7700.00 | Window Closed / Lapsed |