US2223637A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Door operating system
Assignee: National Pneumatic Co Inc
•
Filing: 1939-10-17
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Granted: 1940-12-03
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Expires: 1959-10-17
Abstract
No abstract record available.
Inventors
- 👤 John R Newkirk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:39
CPC Classifications
E; E05; E05F; E05F15/00; E05F15/50; E05F15/53; E05Y; E05Y2201/00; E05Y2201/40; E05Y2201/43; E05Y2201/448; E05Y2800/00; E05Y2800/73; E05Y2900/00; E05Y2900/50; E05Y2900/51
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1943-12-03 | 1944-06-03 | 1944-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-12-03 | 1948-06-03 | 1948-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-12-03 | 1952-06-03 | 1952-12-03 | $7700.00 | Window Closed / Lapsed |