US2310902A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Check valve for door closers
Assignee: MARIE ANNA BOMMER FROHLICH
•
Filing: 1940-05-13
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Granted: 1943-02-09
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Expires: 1960-05-13
Abstract
No abstract record available.
Inventors
- 👤 John F Voelkel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:18
CPC Classifications
E; E05; E05F; E05F3/00; E05F3/04; E05F3/12; E05Y; E05Y2201/00; E05Y2201/20; E05Y2201/23; E05Y2201/232; E05Y2201/234; E05Y2201/252; E05Y2201/254; E05Y2201/40; E05Y2201/43; E05Y2201/448; E05Y2201/458; E05Y2900/00; E05Y2900/10; E05Y2900/13; E05Y2900/132; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7837; Y10T137/7904; Y10T137/7908; Y10T137/7909; Y10T137/7913
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) | 1946-02-08 | 1946-08-10 | 1947-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1950-02-08 | 1950-08-10 | 1951-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1954-02-08 | 1954-08-10 | 1955-02-09 | $7700.00 | Window Closed / Lapsed |