Patent US2514838A successfully refreshed from Google Patents.
US2514838A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nonsticking back-pressure valve
Assignee: Individual
•
Filing: 1946-11-18
•
Granted: 1950-07-11
•
Expires: 1966-11-18
Abstract
No abstract record available.
Inventors
- 👤 Charles J Callahan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:04
CPC Classifications
F; F16; F16K; F16K15/00; F16K15/02; F16K15/03; F16K15/033; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7837; Y10T137/7869; Y10T137/7898
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US345420A
Cited
US371063A
Cited
US420367A
Cited
US580294A
Cited
US769201A
Cited
US1052633A
Cited
US1050646A
Cited
US1480942A
Cited
US1447102A
Cited
US1699085A
Cited
US1725637A
Cited
US1777580A
Cited
US1781366A
Cited
US2048943A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-07-10 | 1954-01-09 | 1954-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-07-10 | 1958-01-09 | 1958-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-07-10 | 1962-01-09 | 1962-07-11 | $7700.00 | Window Closed / Lapsed |