A master cylinder is described. The master cylinder includes a chamber delimited by a piston and supplied from a brake fluid reservoir installed on the top of the master cylinder by an end fitting engaged in a nozzle on the body of the master cylinder. The piston has a nose of reduced section upstream of its skirt guided in the bore hole of the master cylinder and the nozzle is connected to the chamber by a drill hole issuing into the chamber at least partly upstream of the piston in rest position. A valve module is installed in the drill hole to manage communication between the reservoir and the chamber as a function of the position of the piston and the pressure in the chamber with respect to the pressure in the reservoir.

A brake piston system configured for use in a brake system is disclosed. The brake piston system can include: a piston body; a piston footing positioned at a first end of the piston body and configured to transfer a braking force to a brake pad; an o-ring positioned between the piston footing and the piston body. Embodiments of the brake piston system can include a plastic (e.g. phenolic) piston body and a metal (e.g. steel) footing and can reduce fluid hold-up in and weight of the piston system.

A hydraulic device comprises a base member, a piston, a seal ring, and an intermediate member. The base member includes a cylinder bore and an annular groove. The annular groove includes a first inner surface and a second inner surface. The piston is movable relative to the base member from a rest position toward an actuated position in a second direction opposite to a first direction. The piston is movable relative to the base member from the actuated position toward the rest position in the first direction. The seal ring includes a first axial surface facing in the first direction and a second axial surface facing in the second direction. The seal ring is provided in the annular groove so as to define a clearance between the first axial surface and the first inner surface. The intermediate member is provided in the clearance.

An actuation mechanism for a multi-plate disc brake includes an energy storage element configured to apply said disc brake, the energy storage element being movable between a first position where said disc brake is released, and a second position where said disc brake is applied; a force transmission path configured to transmit force from the energy storage element to apply said disc brake; and a hydraulic chamber. The force transmission path includes a first member and a second member arranged in series; wherein the hydraulic chamber is configured, when pressurized, to act on the first member such that the energy storage element is moved to the first position; and wherein the second member is separated from the chamber such that, when the chamber is pressurized, no pressure is applied to the second member.

A spring applied hydraulic released brake includes a brake housing including a pair of stator assemblies, a pair of piston-spring assemblies, each of the piston-spring assemblies including a piston assembly, a spring assembly adapted to apply spring force to the piston assembly to thereby engage the piston assembly with a first stator assembly of the pair of stator assemblies in a default position of the brake, and an end cap adjuster providing an opposing surface against which the spring assembly is biased, the end cap adjuster including a body portion having an end cap threading therearound generally corresponding with a housing threading within the brake housing.

A brake apparatus for a vehicle may include: a brake pad configured to press a brake disk; a screw bar located in a caliper body, and rotatable by power received from a motor unit; a spindle linearly movable by rotation of the screw bar, and coupled to the brake pad; a piston coupled to the spindle so as to cover an outside of the spindle, made of a material having lower hardness than that of the spindle, and movable with the spindle; and a sealing member installed in the caliper body, and contacting the piston.

A sealing assembly for installation on a port of a spring brake actuator includes a plug, a one-way valve and a cap. The plug receives the one-way valve for providing one-way air flow through the orifices and maintaining about two psi in the spring brake chamber at zero stroke. An elastomeric piece is affixed to a first set of segments of the plug for sealing against an inner surface of the port. The cap has arms sized to extend around a third set of segments of the plug and snap onto the plug. A fourth set of segments of the plug elastically deform so the sealing assembly can be installed and removed from the port easily.

The present invention relates to an anti-drag structure of automobile brake calipers, comprising a brake caliper body which is provided with a cylinder bore and a brake claw arranged along the axis of the cylinder bore in an extending mode; and a cylindrical piston bush is pressed in the cylinder bore by interference fit, a step ring groove is formed in the inner wall of the piston bush and composed of a major diameter ring groove and a minor diameter ring groove which have rectangular sections. The present invention can improve the generality of the brake caliper body through the arrangement of the piston bush and improve the standardization of production manufacturing of brake calipers, and can reduce the residual drag moment of the brake caliper and the fuel consumption with the rubber seal ring and the phenolic resin PF ring to achieve the purpose of emission reduction.

A hydraulic caliper assembly includes a caliper brake housing including two opposing pairs of two piston assemblies, each of the pairs of two piston assemblies adapted to place a respective stator assembly of a pair of stator assemblies in a braking position, where the caliper brake housing is a unitary, cast component having an internal fluid porting system fluidly coupling each of the piston assemblies with a source of hydraulic fluid, and where each of the piston assemblies have a common configuration.

A dust boot sealing system for automotive brake cylinders, is arranged for dust protection between a linear actuation member and a housing of the brake cylinder. The boot comprises flexible bellows between two concentrical interface portions, and the both interface portions rest radially outwards from their respective counterpart seats in circumferential grooves on housing and actuation member. The boot is provided with pressure relief valve and with integrated pressure relief valve function which automatically and temporarily changes into open status under a pressure gradient decline in direction from interior to exterior, with respect to the boot.