A spring brake system includes a service brake chamber, a spring brake chamber adjacent to the service brake chamber, a wall separating the service brake chamber from the spring brake chamber, a shaft, and a device. The shaft extends from the service brake chamber into the spring brake chamber through an opening in the wall. The device is disposed along the shaft through the wall, the device being configured to: i) allow air to flow from the service chamber into the spring brake chamber, and ii) prevent air from flowing from the spring brake chamber into the service chamber. The air is within a range that is sufficient to reduce a pressure differential between the service brake chamber and the spring brake chamber. The air is also within a range that is sufficient to generate an anti-compounding effect.

The present disclosure relates to an engagement structure of a push rod guide and a push rod guide cover of a brake chamber for a vehicle, in which a pair of semi-circular, hingedly connected, half members in a shape of a plate are assembled at a side surface of axial direction of the push rod into a shape of a disk, a push rod opening is formed at the center of the disk to guide a movement of the push rod, a protrusion projecting upwards is provided at a central part of the push rod guide, forming a step in a radial direction of the push rod guide, and a receiving groove corresponding to the step is formed on an inner circumferential surface of the push rod guide cover and is connected to the step.

Disclosed herein a caliper brake includes a carrier in which a pair of pad plates are installed to move forward and backward toward a disk; a caliper housing slidably installed on the carrier and provided with a cylinder; a piston installed in the cylinder and configured to move forward and backward toward the pair of pad plates by a braking hydraulic pressure; a seal groove formed to be recessed in an annular shape on an inner surface of the cylinder; and a seal member accommodated in the seal groove, the seal member including a front surface located in a forward direction of the piston; wherein the front surface is provided with a protrusion from which at least a part thereof protrudes.

A brake system for selectively actuating at least one wheel brake includes a reservoir and a power transmission unit for selectively providing pressurized hydraulic fluid for actuating at least a selected one of the wheel brakes during a braking event. A first electronic control unit at least partially controls at least one of the power transmission unit and a selected one of the pair of rear brake motors. A second electronic control unit at least partially controls at least one of the power transmission unit and an other one of the pair of rear brake motors. The first electronic control unit controls at least one SAP valve, an isolation valve, and a dump valve for a selected two of the wheel brakes, and the second electronic control unit controls at least one SAP valve, an isolation valve, and a dump valve for an other two of the wheel brakes.

The application relates to a brake system for a vehicle, comprising a brake piston connectable to a brake pad and configured for performing a braking motion to press the brake pad against a friction surface, a hydraulic brake unit configured for hydraulic actuation of the braking motion, an electro-mechanical parking brake actuator configured for actuating the braking motion comprising a spindle rotatable by an electric motor, and a nut such that a rotational motion of the spindle leads to a translational motion of the nut, wherein the nut is coupled with the brake piston such that a translational motion of the nut toward the brake piston actuates the braking motion of the brake piston, wherein the brake system further comprises an elastic member coupling the brake piston with the nut, configured to drive a motion of the brake piston in a direction opposite the direction of the braking motion.

Disclosed herein an electric parking brake (EPB) that is controlled by an electrical signal and generates a parking braking force includes a caliper housing including a cylinder and a piston slidably provided in the cylinder; and an actuator installed in the cylinder to press and release the piston; wherein the actuator comprises a linear motor installed in the cylinder and having a moving member that moves linearly according to an electrical signal, and a pressing portion that is press-fitted to the moving member to move together with the moving member and presses selectively the piston.

Disclosed herein a caliper brake includes a carrier in which a pair of pad plates are installed to move forward and backward toward a disk; a caliper housing slidably installed on the carrier and provided with a cylinder; a piston installed in the cylinder and configured to move forward and backward toward the pair of pad plates by a braking hydraulic pressure; a seal member in close contact with an outer surface of the piston and an inner surface of the cylinder, the seal member having a ring-shaped; and a seal groove formed to be recessed in the inner surface of the cylinder to accommodate the seal member, the seal groove including a front braking surface facing a front surface of the seal member; wherein the front braking surface includes a protrusion protruding toward the seal member.

A pressure-medium-actuated brake cylinder of a rail vehicle has a housing, a translationally movable brake piston rod extending through a bore in a housing base, a guide ring which is received in the bore, encloses the brake piston rod and is intended for guiding the brake piston rod in the bore, and at least one sealing ring which is received in the bore, encloses the brake piston rod and is intended for sealing an interior of the housing with respect to a space outside the housing, wherein the guide ring and the at least one sealing ring are designed as a guide and sealing ring combined to form a structural unit.

A hydraulic brake wear detection apparatus and a method for detecting a degree of pad wear of a brake pad of a hydraulic brake includes a caliper piston located at least partially within a caliper cavity and attached to the brake pad. The caliper piston includes a piston cavity extending from a caliper piston rim into a caliper piston body at a location longitudinally opposite, and spaced from, the brake pad. An internal piston is located at least partially within the piston cavity and is entirely enclosed in an internal space defined cooperatively by the piston cavity and the caliper cavity for reciprocal longitudinal motion with respect to the internal space. The internal piston is reciprocated by a predetermined volume of pressurized hydraulic fluid responsive to wear of the brake pad.

A piston boot has an annular fixing part that is formed on one end side of a stretchable part and abuts against an inner peripheral side of the cylinder. An outer peripheral surface of the annular fixing part is provided with a first region that abuts against an inner peripheral surface of the cylinder and a second region that is disposed closer to a bottom side of the cylinder than the first region in a piston axial direction. The outer diameter of the first region is larger than the inner diameter of the region of the inner peripheral surface of the cylinder that faces the second region.