US2542259A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Unloader valve
Assignee: Individual
•
Filing: 1947-04-18
•
Granted: 1951-02-20
•
Expires: 1967-04-18
Abstract
No abstract record available.
Inventors
- 👤 Charles M O'leary
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 13:46
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/12; E21B43/121; E21B43/122; E21B43/123; F; F04; F04B; F04B47/00; Y; Y10; Y10T; Y10T137/00; Y10T137/2496; Y10T137/2559; Y10T137/2574; Y10T137/2605; Y10T137/2931; Y10T137/2934; Y10T137/7722; Y10T137/7781; Y10T137/8593; Y10T137/86389; Y10T137/86405; Y10T137/86413
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1543488A
Cited
US2029457A
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US2254631A
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US2269189A
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US2328841A
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US2312201A
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US2342855A
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US2356423A
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US2368999A
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US2423111A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-02-19 | 1954-08-21 | 1955-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-19 | 1958-08-21 | 1959-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-19 | 1962-08-21 | 1963-02-20 | $7700.00 | Window Closed / Lapsed |