Patent US3818295A successfully refreshed from Google Patents.
Patent US3638427A successfully refreshed from Google Patents.
US3638427A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spool valve control for a hydraulic power boost
Assignee: Bendix Corp
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Filing: 1970-04-27
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Granted: 1972-02-01
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Expires: 1990-04-27
Abstract
Abstract A control for a hydraulic power boost assembly in a braking system. Located within a housing of the boost assembly is a control piston which has a projection extending therefrom for abutting a spool valve in a valve chamber. The spool valve is responsive to movement of a brake pedal and regulates hydraulic fluid pressure to move a power piston which activates the master cylinder which in turn supplies fluid pressure to the wheel cylinders of a vehicle. The control piston is a stepped diameter piston which has one end thereof exposed to the fluid pressure in the master cylinder and the other end thereof exposed to the fluid pressure acting on the power piston. Upon manual activation by the brake pedal, the fluid pressure from the master cylinder moves the stepped control piston into engagement with the spool valve thereby preventing it from moving until the brake pedal is released. Such an arrangement prevents sudden surges of hydraulic fluid to the power piston in the power chamber which would cause an abrupt stop of the vehicle.
Inventors
- 👤 Robert E Meyers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:07
CPC Classifications
B; B60; B60T; B60T13/00; B60T13/10; B60T13/12; B60T13/16; B60T13/161; B60T13/162
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
187 words
A hydraulic fluid power boost mechanism for energizing a master cylinder which supplies pressure to the wheel cylinders of a vehicle, comprising: a housing having a power chamber and a valve chamber; piston means located in the power chamber and operatively connected to the master cylinder; valve means located in the valve chamber for controlling flow of fluid to said power chamber which acts on said piston means; actuating means controlled by an operator and operatively connected to said valve means and said piston means; control means operatively connected to said valve means and responsive to the pressure in said master cylinder in the absence of pressure in said power chamber for preventing movement of said valve means when the pressure in the master cylinder exceeds a predetermined value; a control chamber adjacent said valve chamber; and a stepped diameter piston located in said control means which engages said valve means and has one side thereof exposed to the fluid pressure in said master cylinder and the other side thereof exposed to the fluid pressure in said power chamber for limiting the operation of said valve means.
Claim 2
Dependent Claim
187 words
A hydraulic fluid power boost mechanism for energizing a master cylinder which supplies pressure to the wheel cylinders of a vehicle, comprising: a housing having a power chamber and a valve chamber; piston means located in the power chamber and operatively connected to the master cylinder; valve means located in the valve chamber for controlling flow of fluid to said power chamber which acts on said piston means; actuating means controlled by an operator and operatively connected to said valve means and said piston means; control means operatively connected to said valve means and responsive to the pressure in said master cylinder in the absence of pressure in said power chamber for preventing movement of said valve means when the pressure in the master cylinder exceeds a predetermined value; a control chamber adjacent said valve chamber; and a stepped diameter piston located in said control means which engages said valve means and has one side thereof exposed to the fluid pressure in said master cylinder and the other side thereof exposed to the fluid pressure in said power chamber for limiting the operation of said valve means.
Claim 3
Dependent Claim
36 words
The structure, as recited in claim 1, wherein said housing includes: a vent port located between the ends of said stepped diameter piston for preventing mixing of the master cylinder fluid and the brake booster fluid.
Claim 4
Dependent Claim
32 words
The structure, as recited in claim 2, which includes: resilient means located between the stepped piston and the valve means for biasing said valve means against a stop in the valve chambeR.
Claim 5
Dependent Claim
178 words
A power boost assembly for a braking system, comprising: a housing having a power chamber and a valve chamber therein, said valve chamber being connected to a fluid pressure source; a piston member located in said power chamber; actuating means controlled by an operator; valve means located in said valve chamber for regulating fluid flow from said fluid pressure source to said piston member in response to movement of said actuating means; a control chamber in the housing in communication with fluid pressure in said braking system; and pressure responsive means located in said control chamber and operatively connected to said valve means, said pressure responsive means being exposed to and movably responsive to the pressure existing in said braking system and for limiting movement of said valve means, said pressure responsive means having a stepped diameter piston having the large diameter side thereof exposed to the pressure in said valve chamber and the small diameter side thereof exposed to the pressure in said braking system so that the piston is normally urged away from said valve means.
Claim 6
Dependent Claim
178 words
A power boost assembly for a braking system, comprising: a housing having a power chamber and a valve chamber therein, said valve chamber being connected to a fluid pressure source; a piston member located in said power chamber; actuating means controlled by an operator; valve means located in said valve chamber for regulating fluid flow from said fluid pressure source to said piston member in response to movement of said actuating means; a control chamber in the housing in communication with fluid pressure in said braking system; and pressure responsive means located in said control chamber and operatively connected to said valve means, said pressure responsive means being exposed to and movably responsive to the pressure existing in said braking system and for limiting movement of said valve means, said pressure responsive means having a stepped diameter piston having the large diameter side thereof exposed to the pressure in said valve chamber and the small diameter side thereof exposed to the pressure in said braking system so that the piston is normally urged away from said valve means.
Claim 7
Dependent Claim
53 words
In a power boost assembly, as recited in claim 4, wherein said housing includes: a vent port located between the ends of said stepped diameter piston, which ends are sealed in said control chamber and said valve chamber, for preventing mixing of the brake system fluid and the fluid in the valve chamber.
Claim 8
Dependent Claim
80 words
In a power boost assembly, as recited in claim 5, which includes: a stem member connected to said stepped diameter piston; a stop member on said valve means which permits fluid pressure to flow from said valve chamber to said large diameter side of said stepped piston; and a resilient member located between said stem member and said stop member for biasing said stepped diameter piston and said valve means away from each other and against stops in said housing.
Claim 9
Dependent Claim
58 words
In a power boost assembly, as recited in claim 6 wherein said actuating means mechanically operates a master cylinder thereby producing fluid pressure in said control chamber of sufficient magnitude to move the resiliently biased stepped diameter piston into engagement with said valve means and thereby preventing the valve means from moving until said actuating means is released.
Claim 10
Dependent Claim
65 words
In a power boost assembly, as recited in claim 4 wherein said pressure responsive means includes: a stem member having one side exposed to pressure in said valve chamber and the other side exposed to the pressure in said braking system, said stem member engaging said valve means when the differential pressure between said braking system and said valve chamber is above a predetermined value.
Claim 11
Dependent Claim
36 words
In a power boost assembly, as recited in claim 8 which includes: a resilient member located between said stem member and said valve means for biasing said valve means against a stop in the valve chamber.
Claim 12
Dependent Claim
67 words
In a power boost assembly, as recited in claim 9 which includes: a master cylinder operatively connected to said actuating means for supplying fluid to said braking system, said master cylinder upon mechanical actuation producing fluid pressure in said control chamber of sufficient magnitude to move the resiliently biased stem member into engagement with said valve means thereby preventing said valve means from moving during mechanical activation.
Claim 13
Dependent Claim
155 words
A power booster for use in a braking system having valve means for regulating fluid pressure to piston means connected to a master cylinder supplying brake line pressure to the individual wheels of said system, comprising: a housing having a valve bore and a piston bore, said piston means being located in said piston bore, said valve means being located in said valve bore; lever means connecting said valve means with said piston means; actuating means connected to said lever means, said actuating means being responsive to an operator applied force to energize said master cylinder; and pressure responSive means operatively connected to said valve means and said master cylinder, said pressure responsive means having one side exposed to fluid pressure in said valve bore and another side exposed to brake line pressure from said master cylinder for controlling movement of said valve means in proportion to the pressure differential across said pressure responsive means.
Claim 14
Dependent Claim
155 words
A power booster for use in a braking system having valve means for regulating fluid pressure to piston means connected to a master cylinder supplying brake line pressure to the individual wheels of said system, comprising: a housing having a valve bore and a piston bore, said piston means being located in said piston bore, said valve means being located in said valve bore; lever means connecting said valve means with said piston means; actuating means connected to said lever means, said actuating means being responsive to an operator applied force to energize said master cylinder; and pressure responSive means operatively connected to said valve means and said master cylinder, said pressure responsive means having one side exposed to fluid pressure in said valve bore and another side exposed to brake line pressure from said master cylinder for controlling movement of said valve means in proportion to the pressure differential across said pressure responsive means.
Claim 15
Dependent Claim
73 words
The structure as defined in claim 11, wherein said pressure responsive means includes: a piston member sealed in said valve bore opposite said valve means; and a resilient member for biasing said piston member away from said valve means, said brake line pressure needing to overcome the force of said resilient member and said fluid pressure in said valve bore to move said piston member into a limiting position with said valve means.
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) | 1975-01-31 | 1975-08-02 | 1976-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-31 | 1979-08-02 | 1980-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-31 | 1983-08-02 | 1984-02-01 | $7700.00 | Window Closed / Lapsed |