Patent US3818980A successfully refreshed from Google Patents.
Patent US3106064A successfully refreshed from Google Patents.
US3106064A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluid pressure control
Assignee: Dura Corp
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Filing: 1960-10-21
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Granted: 1963-10-08
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Expires: 1980-10-21
Abstract
No abstract record available.
Inventors
- 👤 Stewart B Mcleod
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:38
CPC Classifications
F; F15; F15B; F15B11/00; F15B11/16; F15B11/22
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
218 words
A FLUID PRESSURE SYSTEM, COMPRISING: A PAIR OF HYDRAULIC CYLINDERS DISPOSED IN PARALLEL SPACED RELATION AND HAVING PISTON MEMBERS PROVIDED THEREIN AND PISTON RODS CONNECTED TO SAID PISTON MEMBERS AND EXTENDED THROUGH RESPECTIVELY ADJACENT ENDS OF SAID CYLINDERS, SAID CYLINDERS HAVING FLUID CHAMBERS PROVIDED THEREIN OF RESPECTIVELY DIFFERENT CROSS-SECTIONAL AREAS AND HAVING THE CHAMBER AREA ON ONE SIDE ON ONE OF SAID PISTON MEMBERS BEING OF EQUAL CROSS-SECTIONAL AREA TO THE CHAMBER AREA ON THE OPPOSITE SIDE OF THE OTHER OF SAID PISTON MEMBERS, MEANS CONNECTING SAID CHAMBERS OF EQUAL CROSS SECTIONAL AREA AND PROVIDING FOR THE UNOBSTRUCTED TRANSFER OF FLUID THEREBETWEEN AT ALL TIMES, REVERSIBLE FLUID TRANSFER MEANS PROVIDED BETWEEN THE OTHER OF SAID CHAMBER AREAS FOR ACTIVATING ONE OF SAID PISTON MEMBERS AND THE OTHER THEREOF IN UNISON THEREWITH IN THE COURSE OF FLUID TRANSFER BETWEEN SAID CHAMBERS OF EQUAL AREA, AND SAID PISTON MEMBERS HAVING A COMPLEMENTARY FLUID PRESSURE RESPONSIVE POROSITY PERMISSIVE OF THE FREE EXCHANGE OF FLUID THROUGH EACH OF THE PISTON MEMBERS ONLY UNDER FLUID PRESSURE ABOVE A PREDETERMINED NORMAL OPERATING PRESSURE, AND THE POROSITY OF SAID PISTONS BEING SUCH THAT THE QUANTITY OF FLOW OF FLUID THROUGH THE POROUS PISTONS AT ANY PRESSURE ABOVE THE NORMAL PRESSURE IS SUCH AS TO CAUSE SAID PRESSURE TO MOVE IN SYNCHRONISM AT THE SAME RATE.
Claim 2
Dependent Claim
218 words
A FLUID PRESSURE SYSTEM, COMPRISING: A PAIR OF HYDRAULIC CYLINDERS DISPOSED IN PARALLEL SPACED RELATION AND HAVING PISTON MEMBERS PROVIDED THEREIN AND PISTON RODS CONNECTED TO SAID PISTON MEMBERS AND EXTENDED THROUGH RESPECTIVELY ADJACENT ENDS OF SAID CYLINDERS, SAID CYLINDERS HAVING FLUID CHAMBERS PROVIDED THEREIN OF RESPECTIVELY DIFFERENT CROSS-SECTIONAL AREAS AND HAVING THE CHAMBER AREA ON ONE SIDE ON ONE OF SAID PISTON MEMBERS BEING OF EQUAL CROSS-SECTIONAL AREA TO THE CHAMBER AREA ON THE OPPOSITE SIDE OF THE OTHER OF SAID PISTON MEMBERS, MEANS CONNECTING SAID CHAMBERS OF EQUAL CROSS SECTIONAL AREA AND PROVIDING FOR THE UNOBSTRUCTED TRANSFER OF FLUID THEREBETWEEN AT ALL TIMES, REVERSIBLE FLUID TRANSFER MEANS PROVIDED BETWEEN THE OTHER OF SAID CHAMBER AREAS FOR ACTIVATING ONE OF SAID PISTON MEMBERS AND THE OTHER THEREOF IN UNISON THEREWITH IN THE COURSE OF FLUID TRANSFER BETWEEN SAID CHAMBERS OF EQUAL AREA, AND SAID PISTON MEMBERS HAVING A COMPLEMENTARY FLUID PRESSURE RESPONSIVE POROSITY PERMISSIVE OF THE FREE EXCHANGE OF FLUID THROUGH EACH OF THE PISTON MEMBERS ONLY UNDER FLUID PRESSURE ABOVE A PREDETERMINED NORMAL OPERATING PRESSURE, AND THE POROSITY OF SAID PISTONS BEING SUCH THAT THE QUANTITY OF FLOW OF FLUID THROUGH THE POROUS PISTONS AT ANY PRESSURE ABOVE THE NORMAL PRESSURE IS SUCH AS TO CAUSE SAID PRESSURE TO MOVE IN SYNCHRONISM AT THE SAME RATE.
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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) | 1966-10-07 | 1967-04-08 | 1967-10-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-10-07 | 1971-04-08 | 1971-10-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-10-07 | 1975-04-08 | 1975-10-08 | $7700.00 | Window Closed / Lapsed |