US3021131A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Door opener
Assignee: LIFTRON CORP
•
Filing: 1957-06-20
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Granted: 1962-02-13
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Expires: 1977-06-20
Abstract
No abstract record available.
Inventors
- 👤 William C Bornemann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:25
CPC Classifications
E; E05; E05F; E05F15/00; E05F15/60; E05F15/603; E05F15/665; E05F15/668; E05F15/673; E05Y; E05Y2201/00; E05Y2201/40; E05Y2201/43; E05Y2900/00; E05Y2900/10; E05Y2900/106
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2084733A
Cited
US2253170A
Cited
US2401082A
Cited
US2637550A
Cited
US2589479A
Cited
US2598709A
Cited
US2794634A
Cited
US2882045A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-02-12 | 1965-08-14 | 1966-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-02-12 | 1969-08-14 | 1970-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-02-12 | 1973-08-14 | 1974-02-13 | $7700.00 | Window Closed / Lapsed |