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US3291067A Expired / Lapsed US ⏱️ 0.0 years remaining

Hydrostatic power transmission

Assignee: Boulton Paul Aircraft Ltd
•
Filing: 1965-02-24
•
Granted: 1966-12-13
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Expires: 1985-02-24
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Abstract

No abstract record available.

Inventors

  • 👤 North John Dudley

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 05:17
CPC Classifications
F; F15; F15B; F15B1/00; F15B1/02; F15B1/025; F04; F04B; F04B1/00; F04B1/12; F04B1/20; F04B1/2014; F04B1/2064

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 161 words
A HYDROSTATIC POWER TRANSMISSION INCLUDING A LOW PRESSURE HYDRAULIC ACCUMULATOR CONNECTED TO THE TRANSMISSION PUMP INLET, A LOW PRESSURE BOOST PUMP ARRANGED TO PUMP LIQUID TO THE PUMP INLET, COLLECTING MEANS TO COLLECT LEAKAGE FROM THE PUMP AND TO FEED SUCH LEAKAGE TO THE INLET OF THE BOOST PUMP, AND BY-PASS VALVE CONNECTED BETWEEN THE COLLECTING MEANS AND THE ACCUMULATOR TO MAINTAIN A SUBSTANTIALLY CONSTANT PRESSURE IN SAID COLLECTING MEANS, SAID BY-PASS VALVE COMPRISING A CYLINDER, A PISTON WITHIN THE CYLINDER SPRING-LOADED TO ONE END OF THE THE CYLINDER, VENT MEANS TO CONNECT THE OTHER END OF THE CYLINDER TO ATMOSPHERE, AND A VALVE MEMBER CARRIED BY THE PISTON AND COOPERATING WITH A SEAT LOCATED AT THE SAID ONE END OF THE CYLINDER, WHEREBY THE PRESSURE IN THE COLLECTING MEANS ACTS ON THE PISTON AGAINST THE LOADING OF THE SPRING AND WHEN EXCESSIVE, SEATS THE VALVE TO CLOSE THE BY-PASS AND THUS RAISE THE EFFECTIVE, PUMPING RATE OF THE BOOST PUMP.
Claim 2
Dependent Claim 161 words
A HYDROSTATIC POWER TRANSMISSION INCLUDING A LOW PRESSURE HYDRAULIC ACCUMULATOR CONNECTED TO THE TRANSMISSION PUMP INLET, A LOW PRESSURE BOOST PUMP ARRANGED TO PUMP LIQUID TO THE PUMP INLET, COLLECTING MEANS TO COLLECT LEAKAGE FROM THE PUMP AND TO FEED SUCH LEAKAGE TO THE INLET OF THE BOOST PUMP, AND BY-PASS VALVE CONNECTED BETWEEN THE COLLECTING MEANS AND THE ACCUMULATOR TO MAINTAIN A SUBSTANTIALLY CONSTANT PRESSURE IN SAID COLLECTING MEANS, SAID BY-PASS VALVE COMPRISING A CYLINDER, A PISTON WITHIN THE CYLINDER SPRING-LOADED TO ONE END OF THE THE CYLINDER, VENT MEANS TO CONNECT THE OTHER END OF THE CYLINDER TO ATMOSPHERE, AND A VALVE MEMBER CARRIED BY THE PISTON AND COOPERATING WITH A SEAT LOCATED AT THE SAID ONE END OF THE CYLINDER, WHEREBY THE PRESSURE IN THE COLLECTING MEANS ACTS ON THE PISTON AGAINST THE LOADING OF THE SPRING AND WHEN EXCESSIVE, SEATS THE VALVE TO CLOSE THE BY-PASS AND THUS RAISE THE EFFECTIVE, PUMPING RATE OF THE BOOST PUMP.

References Cited (Backward Citations)

US2769393A Cited
US3003309A Cited
US3046897A Cited
US3066609A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1969-12-12 1970-06-13 1970-12-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1973-12-12 1974-06-13 1974-12-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1977-12-12 1978-06-13 1978-12-13 $7700.00 Window Closed / Lapsed

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