US3590689A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vehicle central hydraulic system
Assignee: Motors Liquidation Co
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Filing: 1969-11-26
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Granted: 1971-07-06
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Expires: 1989-11-26
Abstract
Abstract A central hydraulic system combining the hydraulic power steering gear and a hydraulic power brake booster for operation by a common source of pressurized fluid is arranged to have a primary pump supply the inlet of an open center power steering control valve and have the inlet of the power brake booster open center valve draw from the outlet of the steering gear. In the event the steering gear is caused to engage the chassis limit stops and its control valve held fully actuated so that a condition of substantially reduced flow circulation is established therethrough, a low flow bypass valve delivers incoming pressure fluid from the pump directly to the power brake booster. A secondary electric motor-driven pump is arranged in the system to operate in the event of failure of the primary pump and directly supplies the power steering gear inlet with the low flow bypass valve again being subject to low flow conditions in the latter to directly supply the power brake booster.
Inventors
- 👤 Lee M Brewer
- 👤 William R Frei
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:33
CPC Classifications
B; B62; B62D; B62D5/00; B62D5/06; B62D5/07
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
605 words
In a central fluid system for an automotive vehicle, a source of pressurized fluid, a reservoir, a first fluid servomotor for said vehicle including control valve means of open center flow configuration and having an inlet port and an exhaust port, first conduit means connecting said source with said inlet port, a second fluid servomotor for said vehicle including control valve means of open center flow configuration and having an inlet port and an exhaust port, second conduit means connecting the exhaust port of the first named control valve with the inlet of the last named control valve, third conduit means connecting the exhaust port of the last named control valve with said reservoir, low flow bypass valve means interposed in said first and second conduit means, said valve means including first and second passage meAns within said first conduit means respective to and normally connecting said source and said inlet of said first named control valve and third passage means communicated to said second circuit means and adapted for connection to said source through said first conduit means, said valve means including a valve element movable between a first position connecting said first and second passage means and closing said third passage means and a second position communicating said third passage means with said first and second passage means, means biasing said valve element to said second position thereof, and flow responsive means in said first conduit means counteracting said biasing means to locate said valve element in said first position thereof until flow from said source through said first conduit means reaches a predetermined minimum value. CM,2Central fluid system for an automotive vehicle, a primary source of pressurized fluid, a secondary source of pressurized fluid operative in the event of failure of said primary source, a reservoir, a first fluid servomotor for said vehicle including control valve means of open center flow configuration and having an inlet port and an exhaust port, first conduit means connecting said primary source with said inlet port, a second fluid servomotor for said vehicle including control valve means of open center flow configuration and having an inlet port and an exhaust port, second conduit means connecting the exhaust port of the first named control valve with the inlet of the last named control valve, third conduit means connecting the exhaust port of the last named control valve with said reservoir, fourth conduit means connecting said secondary source with said inlet of said first named control valve, low flow bypass and check valve means interposed in said first, second and fourth conduit means, said valve means including first and second passage means within said first and fourth conduit means respectively, third passage means connected to said inlet of said first named control valve and fourth passage means communicated to said second conduit means and adapted for connection to either of said sources through said first and fourth conduit means, said valve means including a pair of check valves in said first and fourth conduit means preventing communication of said sources therethrough, said valve means further including a valve element movable between a first position connecting said first and second passage means with said third passage means and closing said fourth passage means and a second position communicating said fourth passage means with said first, second and third passage means, means biasing said valve element to said second position thereof, and flow responsive means in said first and fourth conduit means operative to counteract said biasing means to locate said valve element in said first position thereof under flow from either of said sources above a predetermined minumum value.
Claim 2
Dependent Claim
605 words
In a central fluid system for an automotive vehicle, a source of pressurized fluid, a reservoir, a first fluid servomotor for said vehicle including control valve means of open center flow configuration and having an inlet port and an exhaust port, first conduit means connecting said source with said inlet port, a second fluid servomotor for said vehicle including control valve means of open center flow configuration and having an inlet port and an exhaust port, second conduit means connecting the exhaust port of the first named control valve with the inlet of the last named control valve, third conduit means connecting the exhaust port of the last named control valve with said reservoir, low flow bypass valve means interposed in said first and second conduit means, said valve means including first and second passage meAns within said first conduit means respective to and normally connecting said source and said inlet of said first named control valve and third passage means communicated to said second circuit means and adapted for connection to said source through said first conduit means, said valve means including a valve element movable between a first position connecting said first and second passage means and closing said third passage means and a second position communicating said third passage means with said first and second passage means, means biasing said valve element to said second position thereof, and flow responsive means in said first conduit means counteracting said biasing means to locate said valve element in said first position thereof until flow from said source through said first conduit means reaches a predetermined minimum value. CM,2Central fluid system for an automotive vehicle, a primary source of pressurized fluid, a secondary source of pressurized fluid operative in the event of failure of said primary source, a reservoir, a first fluid servomotor for said vehicle including control valve means of open center flow configuration and having an inlet port and an exhaust port, first conduit means connecting said primary source with said inlet port, a second fluid servomotor for said vehicle including control valve means of open center flow configuration and having an inlet port and an exhaust port, second conduit means connecting the exhaust port of the first named control valve with the inlet of the last named control valve, third conduit means connecting the exhaust port of the last named control valve with said reservoir, fourth conduit means connecting said secondary source with said inlet of said first named control valve, low flow bypass and check valve means interposed in said first, second and fourth conduit means, said valve means including first and second passage means within said first and fourth conduit means respectively, third passage means connected to said inlet of said first named control valve and fourth passage means communicated to said second conduit means and adapted for connection to either of said sources through said first and fourth conduit means, said valve means including a pair of check valves in said first and fourth conduit means preventing communication of said sources therethrough, said valve means further including a valve element movable between a first position connecting said first and second passage means with said third passage means and closing said fourth passage means and a second position communicating said fourth passage means with said first, second and third passage means, means biasing said valve element to said second position thereof, and flow responsive means in said first and fourth conduit means operative to counteract said biasing means to locate said valve element in said first position thereof under flow from either of said sources above a predetermined minumum value.
Claim 3
Dependent Claim
194 words
In a central hydraulic system for an automotive vehicle including a source of pressurized fluid, a hydraulic power steering gear having an inlet port and an exhaust port, and a hydraulic servomotor for operating a further item of vehicle control and adapted to utilize exhaust fluid from said steering gear, a low flow bypass valve comprising, a valve body having first and second ports connected with said source and said steering gear inlet respectively, a third port in said housing connected with said steering gear exhaust port, a valve spool slidable in said housing between a first position wherein said first and second ports are communicated and said third port is closed and a second position wherein said first port is communicated with both said second and third ports, spring means biasing said valve spool to the second position thereof, and orifice means on said valve spool in the path of flow from said first to said second port and responsive to flow therethrough to counteract said biasing means to locate said valve spool in the first pOsition thereof until a predetermined minumum rate of flow is reached within said first and second ports.
Claim 4
Dependent Claim
194 words
In a central hydraulic system for an automotive vehicle including a source of pressurized fluid, a hydraulic power steering gear having an inlet port and an exhaust port, and a hydraulic servomotor for operating a further item of vehicle control and adapted to utilize exhaust fluid from said steering gear, a low flow bypass valve comprising, a valve body having first and second ports connected with said source and said steering gear inlet respectively, a third port in said housing connected with said steering gear exhaust port, a valve spool slidable in said housing between a first position wherein said first and second ports are communicated and said third port is closed and a second position wherein said first port is communicated with both said second and third ports, spring means biasing said valve spool to the second position thereof, and orifice means on said valve spool in the path of flow from said first to said second port and responsive to flow therethrough to counteract said biasing means to locate said valve spool in the first pOsition thereof until a predetermined minumum rate of flow is reached within said first and second ports.
Claim 5
Dependent Claim
266 words
In a central hydraulic system for an automotive vehicle including a primary source of pressurized fluid, a secondary source of pressurized fluid operative upon failure of said primary source, a hydraulic power steering gear having an inlet port and an exhaust port, and a hydraulic servomotor for operating a further item of vehicle control and adapted to utilize exhaust fluid from said steering gear, a low flow bypass and check valve comprising, a valve body having first and second ports connected with said primary source and said secondary source respectively, third and fourth ports in said housing connected with said steering gear inlet and exhaust ports respectively, a pair of check valves in said housing functional over said first and second ports to prevent flow from either of said sources therethrough to the other of said sources, a valve spool slidable in said housing between a first position wherein said first and second ports are communicated with said third port and said fourth port is closed and a second position wherein said first and second ports are communicated with both said third and fourth ports, spring means biasing said valve spool to the second position thereof, and orifice means on said valve spool in the paths of flow from said first to said third port and from said second to said third port and responsive to flow through either of such paths from the respective one of said sources to counteract said biasing means and locate said valve spool in the first position thereof until a predetermined minumum rate of flow occurs through said third port.
Claim 6
Dependent Claim
266 words
In a central hydraulic system for an automotive vehicle including a primary source of pressurized fluid, a secondary source of pressurized fluid operative upon failure of said primary source, a hydraulic power steering gear having an inlet port and an exhaust port, and a hydraulic servomotor for operating a further item of vehicle control and adapted to utilize exhaust fluid from said steering gear, a low flow bypass and check valve comprising, a valve body having first and second ports connected with said primary source and said secondary source respectively, third and fourth ports in said housing connected with said steering gear inlet and exhaust ports respectively, a pair of check valves in said housing functional over said first and second ports to prevent flow from either of said sources therethrough to the other of said sources, a valve spool slidable in said housing between a first position wherein said first and second ports are communicated with said third port and said fourth port is closed and a second position wherein said first and second ports are communicated with both said third and fourth ports, spring means biasing said valve spool to the second position thereof, and orifice means on said valve spool in the paths of flow from said first to said third port and from said second to said third port and responsive to flow through either of such paths from the respective one of said sources to counteract said biasing means and locate said valve spool in the first position thereof until a predetermined minumum rate of flow occurs through said third port.
Claim 7
Dependent Claim
66 words
The valve recited in claim 4 wherein said valve spool is constructed with a hollow interior through which flow passes from said first or second ports to said third port, a pair of orifice structures in said spool interior sized respectively to said primary and secondary sources, and a restrictor pin on said housing projecting into said spool interior to function within both said orifice structures.
Claim 8
Dependent Claim
40 words
The valve recited in claim 5 wherein said restrictor pin is sized variably over its length so that the orifices between said pin and said orifice structures increase as said spool moves from the second toward the first position thereof.
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) | 1974-07-05 | 1975-01-04 | 1975-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-05 | 1979-01-04 | 1979-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-05 | 1983-01-04 | 1983-07-06 | $7700.00 | Window Closed / Lapsed |