Patent US2540235A successfully refreshed from Google Patents.
US2540235A
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US
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Fluid operable apparatus
Assignee: HPM Development Corp
•
Filing: 1946-12-13
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Granted: 1951-02-06
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Expires: 1966-12-13
Abstract
No abstract record available.
Inventors
- 👤 Warren D Berkley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:28
CPC Classifications
F; F04; F04C; F04C2/00; F04C2/08; F04C2/082; F04C2/086; F04C15/00; F04C15/0042; F04C15/0046
Claims Analysis
Total Claims: 0
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US2210152A
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US2292331A
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US2281157A
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US2344628A
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US2420622A
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US2413081A
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US2412588A
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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) | 1954-02-05 | 1954-08-07 | 1955-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-05 | 1958-08-07 | 1959-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-05 | 1962-08-07 | 1963-02-06 | $7700.00 | Window Closed / Lapsed |