US 6,149,247 AGranted

Hydraulic brake system for a vehicle

AssigneeRobert Bosch GmbH

InventorsDirk Hofmann, Juergen Binder, Martin Pfau, Eberhardt Schunck

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Abstract

The invention relates to a hydraulic vehicle brake system with a hydraulic pump and a high pressure hydraulic accumulator for external power braking and a conventional master cylinder that is used as a braking power set point adjuster for external power braking and is used to actuate the brake system by muscle power in the event of a failure of the external power brake system. The system connects an intake side of the hydraulic pump to a low pressure hydraulic accumulator into which brake fluid travels from the wheel brake cylinders when the wheel brake pressure decreases. The system has the advantage that no connections of the hydraulic pump to a reservoir of the master cylinder are necessary, which in the event of a leak, would jeopardize the function of both the external power service brake system and the muscle power auxiliary brake system.

Claims5

Dependent claims

A hydraulic vehicle brake system with an external power service brake system and a muscle power auxiliary brake system, comprising a master cylinder (10) that is connected to at least one wheel brake cylinder (16) through a block valve (14), a brake fluid reservoir (12) placed on said master cylinder and which communicates with the master cylinder, a hydraulic pump (18) including a pressure side which is connected directly to a high pressure hydraulic accumulator (24) and is connected to the at least one wheel brake cylinder (16) through a brake pressure increase valve (26), a brake pressure decrease valve (30) that is connected subsequent to the wheel brake cylinder, the vehicle brake system has a fluid tight low pressure hydraulic accumulator (20) being closed in relation to atmosphere and connected to an intake side of the hydraulic pump (18) and connected to the wheel brake cylinder (16) through the brake pressure decrease valve (30).

Dependencies are inferred from the claim text.

Facts

Application: 09/142,757Filed 14 Sep 1998
Priority: DE 197 01 07015 Jan 1997
Granted: 21 Nov 2000
Term ends: Not estimatedThe source records don’t support an estimate.

Classification6 codes

B60T 8/4081
Systems in which a driver input signal is used as a control signal for the additional fluid circuit which is normally used for braking: systems…
B60T 8/3655
Electromagnetic valves specially adapted for anti-lock brake and traction control systems: continuously controlled electromagnetic valves
B60T 8/4072
Comprising an additional fluid circuit including fluid pressurising means for modifying the pressure of the braking fluid, e.g. including wheel…:…
B60T 13/168
Using pumps directly, i.e. without interposition of accumulators or reservoirs: arrangements for pressure supply