Patent US3898913A successfully refreshed from Google Patents.
US3898913A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solenoid control valve for hydraulic brake booster
Assignee: Bendix Corp
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Filing: 1973-09-24
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Granted: 1975-08-12
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Expires: 1993-09-24
Abstract
Abstract An electrically actuated hydraulic brake booster is disclosed which is adapted for use with an automatic brake control system having a device for sensing the distance and relative velocity between vehicles and for automatically actuating the brakes of the vehicle when the automatic control system senses a relative velocity and distance which indicates that a collision is imminent. The electrically actuated brake booster includes a solenoid-operated spool valve which operates in series with the spool valve in the brake booster. The solenoid-actuated valve, when actuated, terminates communication between the booster pressure chamber and pump return, and initiates communication between the booster chamber and the pump outlet. One embodiment of the invention uses a proportional solenoid valve, which exerts a force on the spool valve in proportion to the electrical current transmitted to the solenoid. A second embodiment of the invention uses a two-position solenoid valve to control the spool valve and a second normally open solenoid valve to close a supplemental passage between the solenoid-operated spool valve and the booster pressure chamber. Actuation of the solenoid controlling the spool valve causes a fast brake pressure build rate and actuation of both solenoids causes a slow build up in brake pressure.
Inventors
- 👤 Richard T Hendrickson
- 👤 Richard L Lewis
- 👤 Jerome T Ewald
- 👤 Lloyd G Bach
- 👤 George B Hickner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:43
CPC Classifications
B; B60; B60T; B60T7/00; B60T7/12; B60T13/00; B60T13/10; B60T13/12; B60T13/16; B60T13/161; B60T13/66; B60T13/68; B60T13/686
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
238 words
A vehicle hydraulic system comprising a pump, a hydraulic booster including a housing having an inlet port, an outlet port, and a return port, said housing defining a pressure chamber therewithin, operator-operated valve means shiftable from a first position communicating said pressure chamber with the return port and permitting substantially uninhibited fluid communication between the inlet port and the outlet port, said operatoroperated valve means being shiftable to a second position wheN a booster actuation is effected wherein communication between the pressure chamber and said return port is terminated and the fluid pressure at the inlet port is communicated into the pressure chamber to actuate said booster, electrically operated valve means having a first port, first passage means communicating said first port to the low pressure side of said pump, a second port, second passage means communicating said second port to said return port, a third port, third passage means communicating the third port to said inlet port, a fourth port, fourth passage means communicating said fourth port to the high pressure side of said pump, said electrically operated valve means being responsive to a signal to shift from a first position communicating said first port with said second port and said third port with with fourth port to a second position restricting communication between said third and fourth ports, blocking said first port, and communicating said second port with the fluid pressure level at said fourth port.
Claim 2
Dependent Claim
238 words
A vehicle hydraulic system comprising a pump, a hydraulic booster including a housing having an inlet port, an outlet port, and a return port, said housing defining a pressure chamber therewithin, operator-operated valve means shiftable from a first position communicating said pressure chamber with the return port and permitting substantially uninhibited fluid communication between the inlet port and the outlet port, said operatoroperated valve means being shiftable to a second position wheN a booster actuation is effected wherein communication between the pressure chamber and said return port is terminated and the fluid pressure at the inlet port is communicated into the pressure chamber to actuate said booster, electrically operated valve means having a first port, first passage means communicating said first port to the low pressure side of said pump, a second port, second passage means communicating said second port to said return port, a third port, third passage means communicating the third port to said inlet port, a fourth port, fourth passage means communicating said fourth port to the high pressure side of said pump, said electrically operated valve means being responsive to a signal to shift from a first position communicating said first port with said second port and said third port with with fourth port to a second position restricting communication between said third and fourth ports, blocking said first port, and communicating said second port with the fluid pressure level at said fourth port.
Claim 3
Dependent Claim
28 words
The invention of claim 1: said second passage means including means restricting fluid communication into said return port, said passage means permitting unrestricted communication from said return port.
Claim 4
Dependent Claim
29 words
The invention of claim 2: said second passage means further including a bypass around said restricting means, and a second electrically actuated valve means controlling communication through said bypass.
Claim 5
Dependent Claim
78 words
The invention of claim 1: said electrically operated valve means including a valve element shiftable between said first and second positions, the back pressure developed in said system increasing as said valve element is shifted through intermediate positions between said first and second positions, and a solenoid for shifting said valve element, said solenoid being responsive to the value of said signal to shift said valve elements to a position in accordance with the value of said signal.
Claim 6
Dependent Claim
56 words
The invention of claim 4: said solenoid including an rod engaging said valve element; and a feedback piston slidable relative to said valve element, one end of said feedback piston being adapted to engage said valve element, the other end of said feedback piston being exposed to the fluid pressure level communicated into said pressure chamber.
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) | 1978-08-11 | 1979-02-10 | 1979-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-11 | 1983-02-10 | 1983-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-11 | 1987-02-10 | 1987-08-12 | $7700.00 | Window Closed / Lapsed |