Patent US2811958A successfully refreshed from Google Patents.
US2811958A
Expired / Lapsed
US
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Pressure-operated valve means for free piston engines
Assignee: Motors Liquidation Co
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Filing: 1955-04-18
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Granted: 1957-11-05
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Expires: 1975-04-18
Abstract
No abstract record available.
Inventors
- 👤 Jr Roy W Roush
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 10:00
CPC Classifications
F; F01; F01B; F01B11/00; F02; F02B; F02B71/00; F02D; F02D39/00; F02D39/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1296686A
Cited
US1361109A
Cited
US2162967A
Cited
GB475730A
Cited
US2246701A
Cited
US2301503A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-11-04 | 1961-05-06 | 1961-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-11-04 | 1965-05-06 | 1965-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-11-04 | 1969-05-06 | 1969-11-05 | $7700.00 | Window Closed / Lapsed |