US3614170A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apportioning valves for brake systems
Assignee: Wabco Automotive UK Ltd
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Filing: 1970-04-13
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Granted: 1971-10-19
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Expires: 1990-04-13
Abstract
Abstract An apportioning valve for use in an air pressure braking system comprises piston means responsive to brake line or signal pressure, valve means actuated directly by the piston means and controlling operative pressure air flow to the brake actuators, and a reaction piston responsive to the operative braking pressure and acting on the valve means in opposition to the piston means, the reaction piston acting through a member riding on an inclined plane the angle of which varies with vehicle load thereby varying the degree of reaction for a given braking effort. A relay emergency valve is mounted on or in other association with the apportioning, and it has a service port for connection to a brake control line and an emergency port for connecting to a tractor reservoir, both ports leading to the signal pressure side of the apportioning valve.
Inventors
- 👤 Wilbur Mills Page
- 👤 Ralph Coupland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:18
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/18; B60T8/1837; B60T8/185
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
207 words
For use in a tractor-trailer braking system of the type wherein the tractor and trailer have separate fluid pressure reservoirs, and an apportioning valve assembly on the trailer has valve means for controlling the supply of operating fluid pressure from the tractor reservoir to brake actuator means for the trailer, pressure responsive means for actuating said valve means having an operating chamber adapted to directly receive a signal pressure and pressure-sensitive reaction means responsive to said operating fluid pressure from the tractor reservoir connected for modifying actuating of said valve means in accord with vehicle load, a relay emergency valve assembly having passage means providing fluid communication between said chamber and a port for connection to a source of said signal pressure, control valve means in said passage means and means for applying fluid pressure from said tractor reservoir to hold said control valve in position to maintain said passage means open so that said signal pressure is applied to said chamber to directly operate said valve means, and means effective when said tractor reservoir pressure falls below a predetermined value for connecting and operating said control valve means to apply fluid pressure from said trailer reservoir to said chamber for emergency operation of said trailer brakes.
Claim 2
Dependent Claim
207 words
For use in a tractor-trailer braking system of the type wherein the tractor and trailer have separate fluid pressure reservoirs, and an apportioning valve assembly on the trailer has valve means for controlling the supply of operating fluid pressure from the tractor reservoir to brake actuator means for the trailer, pressure responsive means for actuating said valve means having an operating chamber adapted to directly receive a signal pressure and pressure-sensitive reaction means responsive to said operating fluid pressure from the tractor reservoir connected for modifying actuating of said valve means in accord with vehicle load, a relay emergency valve assembly having passage means providing fluid communication between said chamber and a port for connection to a source of said signal pressure, control valve means in said passage means and means for applying fluid pressure from said tractor reservoir to hold said control valve in position to maintain said passage means open so that said signal pressure is applied to said chamber to directly operate said valve means, and means effective when said tractor reservoir pressure falls below a predetermined value for connecting and operating said control valve means to apply fluid pressure from said trailer reservoir to said chamber for emergency operation of said trailer brakes.
Claim 3
Dependent Claim
48 words
The invention as defined in claim 1, wherein the pressure responsive means in said apportioning valve assembly comprises piston means having one side exposed to said chamber, and said relay emergency valve assembly is mounted on said apportioning valve assembly with said passage means opening into said chamber.
Claim 4
Dependent Claim
61 words
The invention defined in claim 1, wherein said apportioning valve assembly comprises a housing formed with said chamber and said pressure responsive means comprises a movable member having one side exposed to the pressure in said chamber, and said relay emergency valve unit comprises a housing fixed on said apportioning valve housing with Said passage means opening directly into said chamber.
Claim 5
Dependent Claim
47 words
The invention as defined in claim 1, wherein the control valve in said relay emergency valve assembly is actuated by a control piston and means is provided for applying said tractor reservoir pressure to said control piston to hold said control valve in said passage open position.
Claim 6
Dependent Claim
137 words
The invention as defined in claim 4, wherein said relay emergency valve assembly is formed with passage means for applying said tractor reservoir pressure to said control valve piston and also through a further passage means and nonreturn valve to supply charging fluid to said trailer reservoir, said further passage means extending to provide fluid communication between the trailer reservoir and said chamber that is blocked by said control valve means while said tractor reservoir pressure remains above said predetermined value, and said control valve means being spring biased to open said further passage means to permit said trailer reservoir pressure to be applied to said chamber when the tractor reservoir pressure falls below said predetermined value, said further passage means also providing fluid communication between the trailer reservoir and said brake actuator means for the trailer.
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) | 1974-10-18 | 1975-04-19 | 1975-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-18 | 1979-04-19 | 1979-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-18 | 1983-04-19 | 1983-10-19 | $7700.00 | Window Closed / Lapsed |