Patent US3787029A successfully refreshed from Google Patents.
US3787029A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Open center control valve
Assignee: Motors Liquidation Co
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Filing: 1971-09-03
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Granted: 1974-01-22
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Expires: 1991-09-03
Abstract
Abstract A hydraulic power brake booster powered by power steering gear pump pressure and utilizing an open-center valve so that fluid flows through the booster without pressure reduction when the booster is not activated. The valve assembly includes a radially floating valve seat which provides for self-centering, permits a valve separation operation to pass viscous cold hydraulic fluid or any elements which may tend to overly restrict the valve. It also includes a valve face design providing entrance and exit angles defining a venturi-type passage conducive to laminar flow with consequent reduction in valve noise, and has a hydraulic reaction mechanism which includes an arrangement for supported line pressure.
Inventors
- 👤 R Shellhause
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:43
CPC Classifications
B; B60; B60T; B60T13/00; B60T13/10; B60T13/12; B60T13/16; B60T13/161; B60T13/162; B60T13/163
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
174 words
An open center control valve assembly for a hydraulic brake booster comprising: an annular valve seat formed to provide an inner peripheral conical face extending at an angle of substantially 30* from the axis thereof and opening toward the valve assembly inlet, a valve extending into said valve seat and formed to provide an outer peripheral conical face in valving relation with said inner peripheral conical face and defined by a first face conical surface extending at an angle of substantially 29* from the axis thereof and on the inlet side of said valve assembly and a second face conical surface extending at an angle of substantially 31* from the axis thereof and on the outlet side of said valve assembly, means for moving said valve relative to said valve seat to control hydraulic fluid flow therebetween, and means permitting radial movement of said valve seat relative to said valve upon force transmitting contact between said faces to position and retain said valve seat concentrically with respect to and axially aligned with said valve.
Claim 2
Dependent Claim
174 words
An open center control valve assembly for a hydraulic brake booster comprising: an annular valve seat formed to provide an inner peripheral conical face extending at an angle of substantially 30* from the axis thereof and opening toward the valve assembly inlet, a valve extending into said valve seat and formed to provide an outer peripheral conical face in valving relation with said inner peripheral conical face and defined by a first face conical surface extending at an angle of substantially 29* from the axis thereof and on the inlet side of said valve assembly and a second face conical surface extending at an angle of substantially 31* from the axis thereof and on the outlet side of said valve assembly, means for moving said valve relative to said valve seat to control hydraulic fluid flow therebetween, and means permitting radial movement of said valve seat relative to said valve upon force transmitting contact between said faces to position and retain said valve seat concentrically with respect to and axially aligned with said valve.
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) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-21 | 1985-07-23 | 1986-01-22 | $7700.00 | Window Closed / Lapsed |