US2928423A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure relief and valve spool positioning mechanism
Assignee: Allis Chalmers Corp
•
Filing: 1957-12-13
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Granted: 1960-03-15
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Expires: 1977-12-13
Abstract
No abstract record available.
Inventors
- 👤 Harvey W Rockwell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:26
CPC Classifications
E; E02; E02F; E02F9/00; E02F9/20; E02F9/22; F; F15; F15B; F15B13/00; F15B13/02; F15B13/06; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/87265; Y10T137/87338
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2757641A
Cited
US2808120A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-03-15 | 1963-09-14 | 1964-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-03-15 | 1967-09-14 | 1968-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-03-15 | 1971-09-14 | 1972-03-15 | $7700.00 | Window Closed / Lapsed |