Patent US2721541A successfully refreshed from Google Patents.
US2721541A
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US
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Pressure responsive control device for hydraulic apparatus
Assignee: Individual
•
Filing: 1951-05-16
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Granted: 1955-10-25
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Expires: 1971-05-16
Abstract
No abstract record available.
Inventors
- 👤 Nubling Otto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:55
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/38; F16H61/40; F16H61/42; A; A23; A23G; A23G9/00; A23G9/04; A23G9/08; F16H61/423; F16H61/431
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US501959A
Cited
US1793643A
Cited
US1341846A
Cited
US1975138A
Cited
US2139965A
Cited
US2240874A
Cited
US2420155A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-10-24 | 1959-04-25 | 1959-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-10-24 | 1963-04-25 | 1963-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-10-24 | 1967-04-25 | 1967-10-25 | $7700.00 | Window Closed / Lapsed |