Brake system for a motor vehicle

Abstract

A brake system for a motor vehicle includes a master brake cylinder in which a primary piston for generating a brake pressure in a hydraulic brake circuit can be displaced according to actuation of a brake pedal. It is possible to displace the primary piston under the effect of a hydraulic servo pressure circuit in the master brake cylinder. The hydraulic servo pressure circuit includes a pressure source for generating the servo pressure and a pressure accumulator for maintaining a minimum servo pressure in the servo pressure circuit, wherein the discharge line is constructed with a non-return valve which only allows discharge of hydraulic fluid from the pressure accumulator into the servo pressure circuit. A pressure sensor for detecting the hydraulic pressure prevailing in the pressure accumulator is associated with the pressure accumulator.

1 . Brake system for a motor vehicle comprising a master brake cylinder in which a primary piston for generating a brake pressure in a hydraulic brake circuit can be displaced according to actuation of a brake pedal, it being possible to displace the primary piston under the effect of a hydraulic servo pressure circuit in the master brake cylinder and the hydraulic servo pressure circuit comprising a pressure source for generating the servo pressure and a pressure accumulator for maintaining a minimum servo pressure in the servo pressure circuit, wherein the discharge line is constructed with a non-return valve which only allows discharge of hydraulic fluid from the pressure accumulator into the servo pressure circuit, and wherein a pressure sensor for detecting the hydraulic pressure prevailing in the pressure accumulator is associated with the pressure accumulator.  
   
   
       2 . Brake system according to  claim 1 , wherein the servo pressure circuit comprises a manifold valve, in particular a two-way solenoid valve, that is actively controllably interconnected between the master brake cylinder and the pressure source and the pressure accumulator.  
   
   
       3 . Brake system according to  claim 2 , wherein the servo pressure circuit comprises a further manifold valve, in particular a two-way solenoid valve, that is actively controllably interconnected between the master brake cylinder and a hydraulic fluid reservoir.  
   
   
       4 . Brake system according to  claim 1 , wherein the servo pressure circuit comprises a bypass channel that can be activated as a function of pressure and is connected downstream of the pressure source.  
   
   
       5 . Brake system according to  claim 1 , further comprising a controller for evaluating detected hydraulic pressures and for controlling actively controllable components.  
   
   
       6 . Brake system according to  claim 1 , wherein the primary piston is mechanically decoupled from the brake pedal.  
   
   
       7 . Brake system for a motor vehicle comprising a master brake cylinder, wherein a primary piston for generating a brake pressure in a hydraulic brake circuit can be displaced according to actuation of a brake pedal, it being possible to displace the primary piston under the effect of a hydraulic servo pressure circuit in the master brake cylinder, and the hydraulic servo pressure circuit comprising a pressure source for generating the servo pressure, and a pressure accumulator for maintaining a minimum servo pressure in the servo pressure circuit, the pressure accumulator being fluidically connected by a supply line to the servo pressure circuit, and the supply line comprising a fluid supply controller for controlling the supply of hydraulic fluid to the pressure accumulator as a function of the servo pressure prevailing in the servo pressure circuit, characterised in that the fluid supply controller comprises an actively controllable manifold valve, in particular a two-way solenoid valve.  
   
   
       8 . Brake system according to  claim 7 , wherein a pressure sensor is arranged in the servo pressure circuit for detecting the servo pressure.  
   
   
       9 . Brake system according to  claim 7 , wherein the manifold valve is controllable according to the servo pressure detected by the pressure sensor.  
   
   
       10 . Brake system according to  claim 7 , wherein the pressure source comprises a motor-driven pump.  
   
   
       11 . Brake system according to  claim 7 , wherein the servo pressure circuit comprises a non-return valve connected downstream of the pressure source.  
   
   
       12 . Brake system according to  claim 7 , wherein the servo pressure circuit comprises a manifold valve, in particular a two-way solenoid valve, that is actively controllably interconnected between the master brake cylinder and the pressure source and the pressure accumulator.  
   
   
       13 . Brake system according to  claim 12 , wherein the servo pressure circuit comprises a further manifold valve, in particular a two-way solenoid valve, that is actively controllably interconnected between the master brake cylinder and a hydraulic fluid reservoir.  
   
   
       14 . Brake system according to  claim 7 , wherein the servo pressure circuit comprises a bypass channel that can be activated as a function of pressure and is connected downstream of the pressure source.  
   
   
       15 . Brake system according to  claim 7 , wherein a pressure sensor for detecting the hydraulic pressure prevailing in the pressure accumulator is associated with the pressure accumulator.  
   
   
       16 . Brake system according to  claim 7 , further comprising a controller for evaluating detected hydraulic pressures and for controlling actively controllable components.  
   
   
       17 . Brake system according to  claim 7 , wherein the primary piston is mechanically decoupled from the brake pedal.