A method of conducting a diagnostic test to determine leakage within a brake system includes first providing a brake system having a plunger assembly including a housing defining a bore therein. The plunger assembly includes a piston slidably disposed therein such that movement of the piston pressurizes a pressure chamber when the piston is moved in a first direction. The pressure chamber of the plunger assembly is in fluid communication with an output, and wherein the plunger assembly further includes an electrically operated linear actuator for moving the piston within the bore. The linear actuator of the plunger assembly is actuated to provide pressure at the output of the plunger assembly at a first predetermined level. The pressure at the output of the plunger assembly is held for a predetermined length of time. The method further includes determining whether conditional criteria has been met indicating a leakage within the brake system.

A method is provided to check for presence of gas bubbles in an electronically slip-controllable motor vehicle brake system that includes brake circuits to which wheel brakes are connected, a pressure generator to charge the brake circuits with a brake pressure, and sensors to detect an actuating signal of the pressure generator and measure the brake pressures in the brake circuits. Disturbances are recognized by ascertaining from the signal a setpoint value for a brake pressure to be obtained and comparing it to an actual value of the brake pressure or by determining that an actual volume of the pressurizing medium displaced into the brake circuits, ascertainable from the signal, is greater than a limiting value that is determined for a setpoint value for the pressurizing-medium volume to be displaced into the brake circuits in order to generate the actual value of the brake pressure.

A brake device for a vehicle including: a master cylinder unit configured to generate hydraulic pressure by pressing of a pedal; a reservoir connected to the master cylinder unit and configured to store oil; a driving unit operated by movement of the pedal and configured to receive electric energy through a plurality of batteries to supply rotation power; a hydraulic generation unit configured to rotate by receiving the rotation power of the driving unit and generate hydraulic pressure by rotation of a plurality of rotors; wheel cylinder units configured to receive the hydraulic pressure generated by the hydraulic generation unit and constrain rotation of wheels; and a control unit configured to detect whether the driving unit normally operates and control an operation of the driving unit to supply the hydraulic generation unit with the rotation power in an event of abnormal operation of the driving unit.

The present disclosure relates to an electronic brake system and an operation method thereof. The electronic brake system prepares various valves provided on flow paths, that connect components and a reservoir, in a closed state, and then switches the various valves to an open state after a hydraulic pressure of a pressure medium is formed by a hydraulic supply device.

A vehicle control system for controlling braking in a vehicle may include a braking system operably coupled to one or more wheels of the vehicle to provide brake inputs to the one or more wheels responsive to a torque request generated based on pedal position. The system may further include a pedal position sensor operably coupled to a brake pedal to determine the pedal position responsive to actuation of the brake pedal by a driver of the vehicle, a pedal feel simulator operably coupled to the brake pedal to provide tactile feedback to the driver via a pedal force applied to the brake pedal, an accelerometer for determining a rate of velocity reduction of the vehicle during the actuation of the brake pedal, and a feedback augmenter operably coupled to the pedal feel simulator to provide a pedal force offset to increase the pedal force provided to the brake pedal based on the rate of velocity reduction.

A control device is provided with a flow rate derivation part for deriving a pressure-holding-valve flow rate on the basis of a pressure command value and a previous pressure command value; a differential pressure derivation part for deriving a differential-pressure-valve differential pressure value so that the differential-pressure-valve differential pressure value increases with an increase in the difference obtained by subtracting the pressure-holding-valve flow rate from a pump-discharge flow rate; and a pressure-holding-valve processing part for performing an aperture derivation process to derive a command aperture so that the command aperture decreases with an increase in the difference obtained by subtracting the pressure command value from the sum of an pressure value and the differential-pressure-valve differential pressure value, and driving a holding pressure valve at the command aperture.

A brake device includes a first flow path unit guiding a braking hydraulic pressure by connecting some of wheel cylinder units and a master cylinder unit; a second flow path unit guiding a braking hydraulic pressure by connecting the others of the wheel cylinder units and the master cylinder unit; a third flow path unit connecting a reservoir and pump units, and connected with the first flow path unit; a fourth flow path unit connecting the reservoir and the pump units, and connected with the second flow path unit; a fifth flow path unit connecting the reservoir and the first flow path unit; a sixth flow path unit connecting the reservoir and the second flow path unit; a seventh flow path unit selectively connecting the first and second flow path units; and an eighth flow path unit connecting the second flow path unit and the reservoir.

An electro-hydraulic control unit for a vehicle brake system includes a hydraulic control unit including an HCU block defining a motor bore containing an electric motor and an eccentric chamber containing a rotating eccentric driven by the electric motor. The HCU block also defines a pump bore containing a piston pump including a piston rod having a generally cylindrical shape with a smooth exterior surface extending substantially its entire length. An end cap is press fit around an end of the piston rod and includes a flange portion extending annularly outwardly for engaging a return spring. A piston guide includes a tubular portion guiding the piston rod and a shoulder for engaging the return spring. A throat of the piston guide holds a gland seal surrounding the piston rod. An outlet valve housing includes a tubular protrusion extending into the throat of the piston guide to hold the gland seal.

In a method for controlling a hydraulic brake system in a vehicle, wherein the hydraulic brake system is equipped with a hydraulic pump, the hydraulic pump is activated to hold the vehicle at rest and brake fluid is conveyed via open inlet valves to the wheel braking device of a first vehicle axle. The inlet valves on wheel braking devices of a second vehicle axle are at least partially open in response to a change in the brake pressure requirement in the brake system, and at the same time the outlet valves on said wheel braking devices remain closed while the vehicle is being held at rest.

A power piston in a power cylinder borehole of a hydraulic block of a hydraulic power unit of a hydraulic power vehicle braking system is only guided radially in an axially delimited guide section. The power cylinder borehole is configured with a larger diameter axially outside the guide section. A brake fluid channel extends through the guide section up to an opening of a brake fluid line.