A brake system for actuating a pair of front wheel brakes and a pair of rear wheel brakes includes a reservoir and a deceleration signal transmitter. First and second power transmission units are configured for selectively providing pressurized hydraulic fluid during a braking event. The first power transmission unit actuates a selected one of the front wheel brakes and a selected one of the rear wheel brakes. The second power transmission unit actuates the other one of the front wheel brakes and the other one of the rear wheel brakes. First and second electronic control units control the first and second power transmission units. A pair of rear brake motors selectively electrically actuate rear wheel brakes. Multiplex control of each of the pairs of front and rear wheel brakes is provided by an arrangement of first and second parallel valves for each wheel brake.

Disclosed herein a hydraulic supply apparatus includes a motor coupled to a modulator block including flow paths and valves for adjusting brake hydraulic pressure therein, the motor having a stator and a rotor; a sleeve coupled to the rotor to rotate together, and including an accommodating space inside and a first screw thread provided on an inner circumferential surface thereof; a screw shaft provided in the accommodating space, and including a second screw thread meshing with the first screw thread on an outer circumferential surface thereof to convert a rotational motion of the sleeve into a linear motion; and a piston connected to an end of the screw shaft; wherein a central axis of the piston is arranged eccentrically with respect to a central axis of the screw shaft.

Disclosed is a piston pump for a brake system installed in a bore of a modulator block communicating with an inlet port and a discharge port, wherein the piston pump includes: a cylinder unit provided to reciprocate within the bore; a piston unit having one end fixed and the other end dividing the inside of the cylinder unit into a first chamber and a second chamber and configured to expand or reduce the internal spaces of the first chamber and the second chamber by reciprocating movement of the cylinder unit; a first inlet valve installed in the cylinder unit to open and close an one-way flow of fluid from the inlet port to the first chamber; a second inlet valve installed in the cylinder unit to open and close an one-way flow of fluid from the inlet port to the second chamber; and an outlet valve to open and close an one-way flow of fluid from the first chamber or the second chamber to the discharge port.

It is an object of the invention to provide a brake device capable of detecting a failure in each of components, by which booster control is performed, at an early stage even during vehicle running. The brake device is configured to discharge brake fluid into a communicating fluid path that connects a fluid path of a primary system and a fluid path of a secondary system, and to control a first communicating valve for restricting a flow of brake fluid from the communicating fluid path to the fluid path of the primary system and a second communicating valve for restricting a flow of brake fluid from the communicating fluid path to the fluid path of the secondary system in respective valve-closing directions, so as to check at least a state of the pump.

Provided is a brake apparatus capable of securing a braking force on a vehicle even at the time of a fluid leak. The brake apparatus performs control so as to continue generation of a brake hydraulic pressure to be supplied to a wheel cylinder with use of a second hydraulic source if a fluid leak of brake fluid is determined based on a preset relationship between a hydraulic pressure of a first hydraulic source and a stroke of a brake pedal.

A brake system for actuating a pair of front wheel brakes and a pair of rear wheel brakes includes a reservoir and a deceleration signal transmitter. First and second power transmission units are configured for selectively providing pressurized hydraulic fluid during a braking event. The first power transmission unit actuates a selected one of the front wheel brakes and a selected one of the rear wheel brakes. The second power transmission unit actuates the other one of the front wheel brakes and the other one of the rear wheel brakes. First and second electronic control units control the first and second power transmission units. A pair of rear brake motors selectively electrically actuate rear wheel brakes. Multiplex control of each of the pairs of front and rear wheel brakes is provided by an arrangement of first and second parallel valves for each wheel brake.

A piston assembly for a pressure-generating device of a braking system of a motor vehicle, including a piston, which is at least partially insertable into an opening formed in a hydraulic unit of the braking system and is axially displaceable therein, and including a ball screw for axially displacing the piston. The piston is connected to the axially displaceable spindle of the ball screw in such a way that the piston moves along with the axially displaceable spindle of the ball screw, the piston enclosing at least one first portion of the nut in a first, retracted position of the piston and the piston enclosing at most one second portion of the nut in a second, extended position of the piston, and the first portion is larger than the second portion.

The present disclosure relates to a piston pump assembly comprising a piston with a variable stroke and to a hydraulic braking system comprising the same. The piston pump assembly comprises at least: a rotatable drive shaft defining an axis of rotation of the rotatable drive shaft; a cam disposed on the drive shaft; and the piston biased toward the cam and configured to reciprocate along a piston axis for displacing a hydraulic fluid. The cam is movable relative to the piston axis and is selectively placed in one of a first position at a first distance from the piston axis and a second position at a second distance from the piston axis; and wherein the cam comprises at least two portions each of which has, at a given position of the cam relative to the piston axis, a different non-circular cross section in a plane perpendicular to the axis of rotation and/or a different eccentricity with respect to the axis of rotation, the at least two portions of the cam comprising at least a first cam portion having a first non-circular cross section and/or a first eccentricity, and a second cam portion having a second non-circular cross section and/or a second eccentricity.

A hydraulic assembly for a vehicle brake system comprising at least two brake circuits and wheel brakes associated with the brake circuits. The hydraulic assembly comprises a pressure generator for generating a central hydraulic pressure for the brake circuits independently of the driver at least in the case of service braking initiated by the driver. Furthermore, at least one pressure adjusting device is provided for adjusting for each individual brake circuit the central hydraulic pressure that is generated by the pressure generator independently of the driver.

A hydraulic actuation system for a brake system may include at least one brake circuit including at least one wheel brake, a master cylinder that may be actuated using an actuating device and having at least one working chamber, and a hydraulic travel simulator. The working chamber may be connected via a 3/2-way valve either to a brake circuit or to the travel simulator.