Patent US2539977A successfully refreshed from Google Patents.
US2539977A
Expired / Lapsed
US
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Unloading valve
Assignee: Individual
•
Filing: 1946-02-21
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Granted: 1951-01-30
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Expires: 1966-02-21
Abstract
No abstract record available.
Inventors
- 👤 Edwin G Staude
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 11:41
CPC Classifications
F; F04; F04C; F04C14/00; F04C14/24; F04C14/26; F15; F15B; F15B1/00; F15B1/02; F15B1/027; Y; Y10; Y10T; Y10T137/00; Y10T137/2496; Y10T137/2559; Y10T137/2574; Y10T137/2605; Y10T137/2622; Y10T137/2637; Y10T137/7722; Y10T137/7781
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US725707A
Cited
US1103037A
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US1110567A
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US1663647A
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US1888666A
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US2316445A
Cited
US2372016A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-01-29 | 1954-07-31 | 1955-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-29 | 1958-07-31 | 1959-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-29 | 1962-07-31 | 1963-01-30 | $7700.00 | Window Closed / Lapsed |