Patent US3442403A successfully refreshed from Google Patents.
Patent US3120788A successfully refreshed from Google Patents.
US3120788A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Double-acting fluid-pressure jack
Assignee: Individual
•
Filing: 1960-07-06
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Granted: 1964-02-11
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Expires: 1980-07-06
Abstract
No abstract record available.
Inventors
- 👤 Leduc Rene
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:21
CPC Classifications
F; F15; F15B; F15B9/00; F15B9/02; F15B9/08; F15B9/10; F15B1/00; F15B1/02; F15B1/027
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
143 words
A DOUBLE-ACTING FLUID-PRESSURE JACK INCLUDING A CYLINDER, A PISTON MOVABLE IN SAID CYLINDER AND HAVING FORMED THEREIN A FEED DUCT AND AN EXHAUST DUCT, RESPECTIVELY COMMUNICATING WITH A FEED PORT AND AN EXHAUST PORT, A CONTROL ROD COAXIALLY SLIDABLE IN SAID PISTON AND MECHANICALLY UNCONNECTED THEREWITH, AND MEANS CARRIED BY SAID ROD FOR BRINGING ABOUT OPENING AND CLOSURE OF SAID FEED AND EXHAUST PORTS RESPECTIVELY, EACH OF SAID MEANS HAVING A LONGITUDINAL EXTENSION SUPERIOR TO ITS OWN FREE STROKE INSIDE THE SAID PISTON IN EITHER DIRECTION FROM A NEUTRAL RANGE POSITION, SAID FEED AND EXHAUST PORTS BEING SO POSITIONED THAT MOVEMENT OF SAID CONTROL ROD IN EITHER DIRECTION FROM A NEUTRAL RANGE OF POSITION, THE EXTENSION OF WHICH MAY APPROXIMATE TO ZERO, IN WHICH BOTH THE FEED AND EXHAUST PORTS ARE CLOSED, BRINGS ABOUT A MOVEMENT OF THE PISTON IN THE OPPOSITE DIRECTION.
Claim 2
Dependent Claim
143 words
A DOUBLE-ACTING FLUID-PRESSURE JACK INCLUDING A CYLINDER, A PISTON MOVABLE IN SAID CYLINDER AND HAVING FORMED THEREIN A FEED DUCT AND AN EXHAUST DUCT, RESPECTIVELY COMMUNICATING WITH A FEED PORT AND AN EXHAUST PORT, A CONTROL ROD COAXIALLY SLIDABLE IN SAID PISTON AND MECHANICALLY UNCONNECTED THEREWITH, AND MEANS CARRIED BY SAID ROD FOR BRINGING ABOUT OPENING AND CLOSURE OF SAID FEED AND EXHAUST PORTS RESPECTIVELY, EACH OF SAID MEANS HAVING A LONGITUDINAL EXTENSION SUPERIOR TO ITS OWN FREE STROKE INSIDE THE SAID PISTON IN EITHER DIRECTION FROM A NEUTRAL RANGE POSITION, SAID FEED AND EXHAUST PORTS BEING SO POSITIONED THAT MOVEMENT OF SAID CONTROL ROD IN EITHER DIRECTION FROM A NEUTRAL RANGE OF POSITION, THE EXTENSION OF WHICH MAY APPROXIMATE TO ZERO, IN WHICH BOTH THE FEED AND EXHAUST PORTS ARE CLOSED, BRINGS ABOUT A MOVEMENT OF THE PISTON IN THE OPPOSITE DIRECTION.
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) | 1967-02-10 | 1967-08-12 | 1968-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-02-10 | 1971-08-12 | 1972-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-02-10 | 1975-08-12 | 1976-02-11 | $7700.00 | Window Closed / Lapsed |