A method for operating a hydraulic brake system of a motor vehicle includes checking a functional capability of the brake system by detecting a plurality of idle travel values of an actuator before the actuator generates a clamping force, and comparing the idle travel values with a plurality of expected idle travel values of the actuator that are determined as a function of an actuation of a pressure generator. The brake system includes a wheel brake having a brake piston, a brake pedal device, the pressure generator configured to generate a pressure generator force that moves the brake piston in order to active the wheel brake, and the actuator assigned to the wheel brake and configured to generate an actuator force that moves the brake piston in order to activate the wheel brake. The pressure generator and the actuator are actuated such that together they generate a total clamping force.

Electronic brake system is disclosed. An electronic brake system includes, a pressure sensor including a first pressure sensor configured to measure a hydraulic pressure of the accumulator, a second pressure sensor configured to measure a hydraulic pressure of the first hydraulic circuit, and a third pressure sensor configured to measure a hydraulic pressure of the second hydraulic circuit, a driver including one or more apply valves and release valves configured to control the hydraulic pressures of the first hydraulic circuit and the second hydraulic circuit, a determiner configured to determine that at least one of the first hydraulic circuit and the second hydraulic circuit has failed when an absolute value of a slope of the pressure measured by the first pressure sensor is greater than a preset first threshold value and the pressure measured by the first pressure sensor is less than a preset second threshold value and a controller configured to close apply valves of the first hydraulic circuit and the second hydraulic circuit when the failure has been determined, determine that a leak has occurred in one of the first and second hydraulic circuits having an amount of pressure change greater than that of the other hydraulic circuit measured on the basis of the second pressure sensor and the third pressure sensor, and control braking using only the hydraulic circuit operating normally.

A brake booster system for assisting a braking operation of a motor vehicle having a brake booster is provided. The brake booster system may include a pressure piston of a brake master cylinder, an actuating element which is configured for deflecting the pressure piston, and a brake booster which is divided into two chambers by way of a diaphragm, the first chamber is connected to the pressure piston and has a pressure p1 and the second chamber is connected to the actuating element and has a pressure p2. Furthermore, in the brake booster system, there is a pressure build up apparatus which is configured to raise the pressure p2 above the pressure p1 by way of said pressure build up apparatus.

A vehicle braking unit comprises an operating braking pressure inlet which receives an inlet braking pressure built up by a braking cylinder, and at least one operating brake pressure outlet at which an outlet braking pressure is provided for an operating brake modulator, which is upstream of the operating brake and provides anti-lock functionality. At least one connecting channel hydraulically connects the operating brake pressure inlet to the outlet. Brake fluid is supplied from a storage unit through the brake cylinder, the connecting channel and the operating brake modulator. The braking unit has a brake fluid inlet, through which the brake fluid is received from the storage unit, a brake fluid pump, by which the brake fluid is suctioned through the brake fluid inlet and a supply pressure is built up, and a valve unit that controls the outlet braking pressure and/or a parking brake release pressure by the supply pressure.

A brake ECU of a vehicle braking control device, during execution of brake pressurization control, performs actuation restriction control that restricts actuation of a motor as an arbitrary upstream fluid pressure (M/C pressure) that is the brake pressure input from the M/C side of the brake fluid pressure control actuator becomes higher. The brake ECU has a threshold value changing unit that sets at least the starting threshold value at a high level when the upstream fluid pressure (M/C pressure) is high compared to when low, and as actuation restriction control actuates the motor to pump out the brake fluid from inside of the reservoirs when the reservoir fluid volume exceeds the starting threshold value, and stops the motor when the reservoir fluid volume equals the stop threshold value.

The invention relates to an actuating device for a motor vehicle brake, comprising the following components: an actuating apparatus, in particular in the form of a brake pedal, a pressure-supply device (11) which is driven by an electromotive drive (M) and is in the form of a piston pump or a double-stroke piston pump, a piston-cylinder unit (10, master cylinder) which can be actuated by the actuating apparatus and is hydraulically connected to the pressure medium reservoir vessel (VB) and which forms at least two pressure spaces which are connected to hydraulic brake circuits a valve arrangement (HCU) having valves for the wheel-specific adjustment of brake pressures and for disconnecting or connecting the wheel brakes to the pressure supply device (11) and/or the piston-cylinder unit (10), an electronic control unit (ECU),
wherein the axis (A.sub.1) of the piston-cylinder unit (10, master cylinder) and the axis (A.sub.2) of the piston pump or double-stroke piston pump of the pressure supply unit (11) are arranged transversely with respect to one another,
characterised in that
the piston-cylinder unit (10, master cylinder) and the pressure supply unit (11) are arranged in a first housing (GH1), wherein the motor (M), the first housing (GH1), the valve arrangement (HCU) and the electronic control unit (ECU) are arranged stacked one on top of the other, and in that the axis (A.sub.1) of the piston-cylinder unit (10) is arranged transversely with respect to the stacking direction (SR) and the axis (A.sub.2) of the pressure supply device (11) is arranged parallel to the stacking direction (SR), wherein the stacking direction (SR) is arranged parallel to the vertical (V) or at an angle () of 5 to 30 with respect to the vertical (V).

The invention relates to an actuating device for a motor vehicle brake, comprising the following components: an actuating device, in particular in the form of a brake pedal, a pressure supply device (11), in particular a reciprocating pump or double-acting reciprocating pump, driven by an electric motor drive (M), a piston-cylinder unit (main cylinder) (10) that can be actuated by means of the actuating device, that is connected hydraulically with a hydraulic fluid reservoir (BFR) and that forms at least two pressure chambers that are connected with hydraulic brake circuits, a valve assembly (HCU) with valves for adjusting brake pressures in a wheel-specific manner and for disconnecting or connecting the wheel brakes from or to the pressure supply device (11) and the piston-cylinder unit (10), an electronic control unit (ECU), at least one sensor device, having at least one sensor or evaluation element (3, 4, 5, 24, 24a) and a sensor target (5a, 23, 23a), preferably based on an electromagnetic principle,
for sensing a movement of a device component.

According to the invention,

at least one sensor or evaluation element (3, 4, 5, 24, 24a) of the sensor device is arranged on or in the electronic control unit (ECU), in particular on a system printed circuit board (PCB) of the control unit (25), and
that a movement of the device component (10; 45; 46; 48) is transmitted to the electronic control unit (ECU) (25) via a sensor actuating device, in particular via a mechanical actuating mechanism (17, 18, 19) or via a sensor target (5a, 23, 23a) connected with the device component and magnetic flux-conducting components (43, 43, a, 43b) based on ferromagnetic materials.

A method for providing a brake force in a vehicle with a hydraulic vehicle brake and an electromechanical brake device includes determining a position of a brake piston at a brake contact point on the basis of a state variable of an electric brake motor when the electromechanical brake device is released. The method further includes displacing the brake piston in a positioning operation until reaching a braking start point.

This disclosure is applicable to intelligent automobiles, new energy automobiles, conventional automobiles, or the like. In an example embodiment, a fluid outlet pipe of a first hydraulic chamber is configured in segments on a push rod support portion and a push rod. When a piston is located at an inner stop point of a piston stroke, a first hydraulic adjustment port located on the push rod support portion communicates with a second hydraulic adjustment port located on the push rod, and when the piston is located at a position other than the inner stop point in the piston stroke, the first hydraulic adjustment port does not communicate with the second hydraulic adjustment port.

A PCM (50) that is an engine control device functions to acquire a master vac negative pressure which is the negative pressure of a stabilized chamber of a master vac (126) which amplifies a brake pedal depressing force applied to a brake pedal (102), and also acquire a brake working fluid pressure that is a braking hydraulic pressure produced by a master cylinder (144) in accordance with the brake pedal depressing force amplified by the master vac (126), and in a case where both accelerator pedal (104) and a brake pedal (102) are depressed or actuated simultaneously, determine whether or not it is necessary to decrease engine output based on such master vac negative pressure and brake working fluid pressure to execute the output decreasing control for decreasing the engine output.