US3120816A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic pumps and motors
Assignee: Council of Scientific and Industrial Research
•
Filing: 1960-04-14
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Granted: 1964-02-11
•
Expires: 1980-04-14
Abstract
No abstract record available.
Inventors
- 👤 Firth Donald
- 👤 Roger H Y Hancock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:18
CPC Classifications
F; F16; F16C; F16C32/00; F16C32/06; F16C32/0662; F16C32/0666; F01; F01B; F01B3/00; F01B3/0032; F01B3/0082; F01B3/0085; F04; F04B; F04B1/00; F04B1/12; F04B1/122; F04B1/124; Y; Y10; Y10T; Y10T74/00; Y10T74/18; Y10T74/18056; Y10T74/18296; Y10T74/18336; Y10T74/21; Y10T74/2101; Y10T74/2107
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
135 words
IN A POSITIVE DISPLACEMENT HYDRAULIC MACHINE, THE COMBINATION WITH A RECIPROCABLE PISTON OF A SLIPPER ARTICULATED TO SAID PISTON; A PISTON TRUST REACTION MEMBER ON WHICH SAID SLIPPER IS SLIDABLE; AT LEAST TWO SEPARATE OIL RETAINING RECESSES SYMMETRICALLY DISPOSED WITH RESPECT TO THE MIDPOINT OF THE SLIDING FACE OF SAID SLIPPER; EACH OF SAID RECESSES EXTENDING FROM A POINT ADJACENT THE CENTER OF SAID SLIDING FACE TOWARDS THE PERIPHERY THEREOF AND BOUNDED ON ALL SIDES BY A CONTINUOUS LAND; SEPARATE DUCTS COMMUNICATING BETWEEN THE PRESSURE SIDE OF SAID PISTON AND SAID RECESSES; AND A METERING CONSTRICTION IN EACH DUCT FOR CONTROLLING THE SUPPLY OF WORKING FLUID TO SAID RECESS WHEREBY SAID SLIPPER IS RESTORED TO ITS NORMAL OPERATING POSITION BY AT LEAST ONE OF SAID RECESSES WHEN SAID SLIPPER IS MOVED FROM SAID REACTION MEMBER.
Claim 2
Dependent Claim
135 words
IN A POSITIVE DISPLACEMENT HYDRAULIC MACHINE, THE COMBINATION WITH A RECIPROCABLE PISTON OF A SLIPPER ARTICULATED TO SAID PISTON; A PISTON TRUST REACTION MEMBER ON WHICH SAID SLIPPER IS SLIDABLE; AT LEAST TWO SEPARATE OIL RETAINING RECESSES SYMMETRICALLY DISPOSED WITH RESPECT TO THE MIDPOINT OF THE SLIDING FACE OF SAID SLIPPER; EACH OF SAID RECESSES EXTENDING FROM A POINT ADJACENT THE CENTER OF SAID SLIDING FACE TOWARDS THE PERIPHERY THEREOF AND BOUNDED ON ALL SIDES BY A CONTINUOUS LAND; SEPARATE DUCTS COMMUNICATING BETWEEN THE PRESSURE SIDE OF SAID PISTON AND SAID RECESSES; AND A METERING CONSTRICTION IN EACH DUCT FOR CONTROLLING THE SUPPLY OF WORKING FLUID TO SAID RECESS WHEREBY SAID SLIPPER IS RESTORED TO ITS NORMAL OPERATING POSITION BY AT LEAST ONE OF SAID RECESSES WHEN SAID SLIPPER IS MOVED FROM SAID REACTION MEMBER.
References Cited (Backward Citations)
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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) | 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 |