US2946931A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photoelectric control system for door operation and the like
Assignee: National Pneumatic Co Inc
•
Filing: 1956-03-12
•
Granted: 1960-07-26
•
Expires: 1976-03-12
Abstract
No abstract record available.
Inventors
- 👤 Durbin Vernon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:12
CPC Classifications
E; E05; E05F; E05F15/00; E05F15/70; E05F15/73; E05F15/74
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US666737A
Cited
US2016036A
Cited
US1949689A
Cited
US2057384A
Cited
US1985563A
Cited
US2054380A
Cited
US2145021A
Cited
US2697803A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-07-26 | 1964-01-25 | 1964-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-07-26 | 1968-01-25 | 1968-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-07-26 | 1972-01-25 | 1972-07-26 | $7700.00 | Window Closed / Lapsed |