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US2638993A
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US
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Hydraulic control apparatus for internal-combustion engines and variable pitch propellers
Assignee: Niles Bement Pond Co
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Filing: 1947-10-01
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Granted: 1953-05-19
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Expires: 1967-10-01
Abstract
No abstract record available.
Inventors
- 👤 James S Woodward
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 06:34
CPC Classifications
F; F02; F02D; F02D29/00; F02D2700/00; F02D2700/07
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2207042A
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US2217364A
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US2308228A
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US2322303A
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US2343378A
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US2391629A
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US2412360A
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US2303998A
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US2402065A
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US2428531A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-05-18 | 1956-11-17 | 1957-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-18 | 1960-11-17 | 1961-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-18 | 1964-11-17 | 1965-05-19 | $7700.00 | Window Closed / Lapsed |