Patent US4330613A successfully refreshed from Google Patents.
Patent US3262531A successfully refreshed from Google Patents.
US3262531A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Clutch with dual pistons for quick slack take up
Assignee: Twin Disc Inc
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Filing: 1964-05-28
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Granted: 1966-07-26
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Expires: 1984-05-28
Abstract
No abstract record available.
Inventors
- 👤 James B Black
- 👤 Conrad R Hilpert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:47
CPC Classifications
F; F16; F16D; F16D25/00; F16D25/10; F16D25/06; F16D25/062; F16D25/063; F16D25/0635; F16D25/0638
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
132 words
A HYDRAULICALLY OPERATED CLUTCH MECHANISM COMPRISING A PAIR OF CLUTCHES HAVING A COMMON SHAFT, A MAIN PISTON SHIFTABLE ON THE OUTSIDE OF AND SURROUNDING SAID SHAFT AND LOCATED BETWEEN SAID CLUTCHES, AN ANNULAR REACTION MEMBER WITHIN AND ENCLOSED BY SAID MAIN PISTON AND FIXED ON SAID SHAFT TO DEFINE A PAIR OF LARGE, VARIABLE VOLUME, PRESSURE FLUID CHAMBERS, A PAIR OF PRIMARY PISTONS MOUNTED ON THE OUTSIDE OF SAID MAIN PISTON AND ONE ON EACH SIDE OF SAID MAIN PISTON AND SLIDABLY ENGAGEABLE THEREWITH TO DEFINE A PAIR OF SMALL VARIABLE VOLUME CHAMBERS, EACH OF SAID PRIMARY PISTONS BEING ENGAGEABLE WITH ITS RESPECTIVE CLUTCH, AND PASSAGE MEANS IN SAID MAIN PISTON FOR SUPPLYING FLUID TO BOTH OF SAID LARGE AND SMALL CHAMBERS, AND VALVE MEANS TO PREVENT RETURN FLOW OF SAID FLUID.
Claim 2
Dependent Claim
132 words
A HYDRAULICALLY OPERATED CLUTCH MECHANISM COMPRISING A PAIR OF CLUTCHES HAVING A COMMON SHAFT, A MAIN PISTON SHIFTABLE ON THE OUTSIDE OF AND SURROUNDING SAID SHAFT AND LOCATED BETWEEN SAID CLUTCHES, AN ANNULAR REACTION MEMBER WITHIN AND ENCLOSED BY SAID MAIN PISTON AND FIXED ON SAID SHAFT TO DEFINE A PAIR OF LARGE, VARIABLE VOLUME, PRESSURE FLUID CHAMBERS, A PAIR OF PRIMARY PISTONS MOUNTED ON THE OUTSIDE OF SAID MAIN PISTON AND ONE ON EACH SIDE OF SAID MAIN PISTON AND SLIDABLY ENGAGEABLE THEREWITH TO DEFINE A PAIR OF SMALL VARIABLE VOLUME CHAMBERS, EACH OF SAID PRIMARY PISTONS BEING ENGAGEABLE WITH ITS RESPECTIVE CLUTCH, AND PASSAGE MEANS IN SAID MAIN PISTON FOR SUPPLYING FLUID TO BOTH OF SAID LARGE AND SMALL CHAMBERS, AND VALVE MEANS TO PREVENT RETURN FLOW OF SAID FLUID.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-07-25 | 1970-01-24 | 1970-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-07-25 | 1974-01-24 | 1974-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-07-25 | 1978-01-24 | 1978-07-26 | $7700.00 | Window Closed / Lapsed |