US2831638A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air control device
Assignee: Individual
•
Filing: 1954-07-14
•
Granted: 1958-04-22
•
Expires: 1974-07-14
Abstract
No abstract record available.
Inventors
- 👤 Chester K Fulk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:26
CPC Classifications
H; H05; H05B; H05B1/00; H05B1/02; H05B1/0202; H05B1/0213; F; F24; F24F; F24F11/00; F24F11/70; F24F11/72; F24F11/74; F24F11/76
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US29307A
Cited
US1818546A
Cited
US1676923A
Cited
US1583496A
Cited
US1726225A
Cited
US1778560A
Cited
FR711150A
Cited
US2342998A
Cited
US2552966A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-04-21 | 1961-10-21 | 1962-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-04-21 | 1965-10-21 | 1966-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-04-21 | 1969-10-21 | 1970-04-22 | $7700.00 | Window Closed / Lapsed |