A brake system for a vehicle is disclosed herein, which is constructed for selective pressurisation and pressure relief of at least two pressure connections for brake actuators. The brake system comprises an electrofluidic pressure generation unit, a main cylinder unit and an electrofluidic pressure increase unit, which is fluidly coupled at the input side to the electrofluidic pressure generation unit and/or the main cylinder unit in such a manner that exclusively a volume flow of pressure fluid which is pressurised by the electrofluidic pressure generation unit and/or the main cylinder unit can be acted on with a supplementary pressure by the pressure increase unit. At the output side, the pressure increase unit is connected in fluid terms to one of the pressure connections. In addition, a method for operating such a brake system is set out.

A diagnostic method to identify a leak in simulator valve in a vehicle brake system includes the steps of: (1) providing a simulator partially filled with a pressure medium and a de-energized simulator valve; (2) energizing a pumping valve, a secondary three-way valve, and a plurality of apply valves; (3) applying and retracting a plunger in a plunger assembly at least two cycles so that a predetermined pressure is achieved; (3) holding a plunger in position within the plunger assembly while maintaining a replenishing check valve in a closed/de-energized position and energizing the simulator valve; (4) obtaining a measured master cylinder secondary pressure decay; (5) comparing the measured master cylinder secondary pressure decay to a predetermined pressure decay value; and (7) identifying a leak in the simulator valve if the measured master cylinder secondary pressure decay does not match the predetermined master cylinder secondary pressure decay.

A method for detecting a resistance on a brake pedal of a brake system, in which a brake pedal is pulled by an actuator, in which an ease of movement of the brake pedal is determined during operation of the actuator, wherein a resistance is detected as soon as the ease of movement is no longer clearly determined, and a method for controlling an actuator, a computer program product, control unit or system comprising a plurality of control units, and a corresponding device.

A diagnostic method to identify a leak in a three-way valve for a vehicle brake system having a remote master cylinder which includes the steps of: (1) providing a pedal simulator having pressure medium; (2) de-energizing a secondary three-way valve; (3) retracting a dual acting plunger to the home position to drop the pressure in the boost circuit to zero while also monitoring the pressure at the output of a fluid separator via a secondary master cylinder pressure sensor; (4) determining a rate of pressure reduction at the output of a fluid separator via a secondary master cylinder pressure sensor; and (5) identifying a leak in at least one of a primary three-way valve and the secondary three way valve if the rate of pressure reduction is equal to or higher than a pre-determined rate.

A method for operating a brake system of a motor vehicle, wherein the brake system has a brake pedal, which can be actuated by a driver of the motor vehicle, a brake booster, which can be coupled or is coupled to the brake pedal, a brake cylinder, such as a brake master cylinder, which can be coupled or is coupled to the brake booster and can be supplied with hydraulic fluid, and a hydraulic arrangement, which acts between the brake cylinder and at least one wheel brake, wherein the method comprises at least the step of: decoupling the brake pedal from the at least one wheel brake by the hydraulic arrangement, and a computer program, control unit or system having a plurality of control units and brake system.

The invention relates to a brake system for motor vehicle. A piston-cylinder arrangement can be actuated by means of a brake pedal, a controllable pressure source and brake pressure modulation valves. In order to provide a piston-cylinder arrangement which is easy to implement and axially short, the invention proposes that the piston of the piston-cylinder arrangement is directly guided in a housing that accommodates further components of the brake system according to the invention.

A hydraulic brake system for braking a vehicle, including a master cylinder device having a fluid-flow permission mechanism that permits a flow of a working fluid between an inter-piston chamber and a low-pressure source, wherein, when a pressure of the working fluid to be supplied to a brake device exceeds a set pressure upon advancing in association with an advancing movement of a brake operation member, a closing and opening mechanism for hermetically closing the inter-piston chamber and opening an opposing chamber to the low-pressure source is controlled so as to hermetically close the inter-piston chamber, while, when the pressure of the working fluid becomes lower than a set pressure upon retracting in association with a retracting movement of the brake operation member, the fluid-flow permission mechanism is controlled so as to permit the flow of the working fluid between the inter-piston chamber and the low-pressure source.

A brake control device capable of preventing a braking force from being excessive when information cannot be transmitted between a first control unit configured to control operation of a boost mechanism and a second control unit configured to control operation of a hydraulic control mechanism. When a second ECU (32) cannot transmit information to a first ECU (26) due to a disconnection of a signal line (27), the second ECU carries out backup control of detecting a braking operation amount of a driver based on signal input from hydraulic pressure sensors (29), and operating a hydraulic pressure supply device (30) based on the detected braking operation amount, to thereby pressurize insides of wheel cylinders. In this case, the second ECU decreases a pressurization amount of a pressure inside the wheel cylinders when a pressure of a master cylinder (8) exceeds a predetermined value (PM0) during the backup control.

A braking system, in particular for a motor vehicle, including a braking force device having a brake booster for boosting a braking force and a brake pressure supply device for providing brake pressure with the aid of a brake medium, a braking device which may be acted on by pressure by the brake medium with the aid of the brake pressure supply device, and at least one sensor which is designed to detect a distance differential of a displacement means for the displacement of a volume of the brake medium of the braking force device. The braking force device is designed to ascertain the volume of brake medium to be displaced on the basis of the detected distance differential.

A brake system includes a stroke sensor to output a detection signal indicative of a status of a stroke of a brake pedal, and a first controller to receive the detection signal and to generate a switching signal in accordance with a displacement of the brake pedal based on a result of comparing the detection signal with a predetermined reference value. In particular, the switching signal is provided to at least one second controller configured to control an operation of another device in a vehicle based on an operation of the brake pedal.