A brake actuator comprises a housing having an end wall and a pushrod projecting through an opening in the end wall and terminating at a movable plate in the housing. A spring is enclosed in the housing and surrounds the pushrod. At least one unitary resilient member is disposed on the push rod proximate to the end wall and partially extends through the opening for centering the spring around an axis of the pushrod and restricting contamination into the housing. The unitary resilient member comprises a central aperture and an annular flange surrounding the central aperture. At least one section of a collar radially outward from the annular flange has a thickness less than half of the annular flange thickness for constraining movement of the spring and the push rod in a radial direction.

A disk brake for a utility-vehicle wheel includes a brake caliper reaching around a brake disk, an application device arranged in the brake caliper on one side of the brake disk actuated by means of a force member, brake pads on both sides of the brake disk. At least the application-side brake pad is arranged in a pad duct having first and second supporting surfaces which have the same distance from a pad duct center line in the circumferential direction, and against which the brake pad lies, a brake lever which is part of the application device and is composed of a lever arm supporting the force member, and an application shaft connected to the lever arm and mounted inside the brake caliper on a pivot axis and resting in a rotationally movable manner against a pressure piece working against the application-side brake pad.

An air disc brake system includes a carrier and a guide pin mounted to the carrier. A caliper is slidably mounted on the guide pin. The caliper has an annular groove extending radially outwardly from an inner circumferential surface. The caliper is moveable relative to the guide pin from a non-braking position to a braking position. A friction ring is disposed in the annular groove and is deformable from a first configuration when the caliper is in the non-braking position to a second configuration when the caliper is in the braking position. The friction ring biases the caliper from the braking position to the non-braking position. Methods of using and assembling the air disc brake system are also provided.

A pneumatic brake actuator has a spring brake actuator with spring and spring brake pressure chambers, and a service brake actuator with service brake pressure and pushrod chambers. A control valve has a seal that is moveable between an open position and a closed position for regulating fluid flow between the spring chamber and service brake pressure chamber. A first surface of the seal is in fluid communication with the service brake pressure chamber and a second surface of the seal is in fluid communication with a valve chamber that is not in fluid communication with the service brake pressure chamber or spring chamber. The seal moves between its open and closed positions based on a pressure in the service brake pressure chamber. Movement of the seal is not dependent on the rate of flow of fluid between the spring chamber and the service brake pressure chamber.

Provided is a railway vehicle disc brake apparatus that is capable of ensuring sufficient strength and that can be reduced in weight. The railway vehicle disc brake apparatus has: a pair of calliper levers for supporting a pair of pads; a pair of fulcrum shaft members that pivotally support the pair of calliper levers; and a cylinder device for driving the pair of calliper levers around the pair of fulcrum shaft members. Arm sections of the calliper lever have first and second portions that extend in such a manner as to intersect each other in a cross section that is perpendicular to the direction in which said arm sections extend.

A spring-type brake actuator for a vehicle brake such as a pneumatically-actuated brake is provided, in which the actuator's operating rod is pulled toward the actuator to apply the brake. The actuator's parking brake release piston is located closer to the brake than the service brake piston, and the parking brake power spring is positioned between the mounting end of the actuator and the parking brake piston such that when parking brake release pressure is removed from the parking brake release chamber the parking brake piston biases the operating rod in the brake application direction, drawing the operating rod further into the actuator. The operating rod may penetrate the parking brake piston and an intermediate flange between the parking brake piston and the service brake piston, and be connected to the service brake piston such that the service brake piston may control brake application when the parking brake piston is in its parking brake release position adjacent to the end of the actuator that is mounted to the brake.

A pneumatic brake actuator has a spring brake actuator with spring and spring brake pressure chambers, and a service brake actuator with service brake pressure and pushrod chambers. A control valve has a seal that is moveable between an open position and a closed position for regulating fluid flow between the spring chamber and service brake pressure chamber. A first surface of the seal is in fluid communication with the service brake pressure chamber and a second surface of the seal is in fluid communication with a valve chamber that is not in fluid communication with the service brake pressure chamber or spring chamber. The seal moves between its open and closed positions based on a pressure in the service brake pressure chamber. Movement of the seal is not dependent on the rate of flow of fluid between the spring chamber and the service brake pressure chamber.

The present invention relates to a brake system comprising an actuating part and a brake part, the actuating part having a pressure chamber and a restoring section, the pressure chamber and the restoring section being separated from one another in a fluid-tight manner by way of a piston, it being possible for the piston to be fixed on an engagement element in such a way that a movement of the piston brings about a movement of the engagement element, the engagement element protruding into the brake part and having, in the brake part, a force section which is designed to transmit a force to a brake means, the brake part and the predominant part of the actuating part being arranged in a housing.

A disc brake, preferably a compressed air-actuated disc brake, in particular for a motor vehicle, has a brake application mechanism with a brake rotary lever, at least one spindle unit having a threaded rod screwed into a bridge, and a brake caliper. The caliper frames an edge region of a brake disc. The brake caliper has a brake application portion and a caliper back which are connected together via tie bars. The brake application mechanism with the brake rotary lever is received in the brake application portion of the brake caliper from an application face side of the brake disc. The brake application portion of the brake caliper has a first region, in which the application mechanism and a force transmission portion of the brake rotary lever are arranged, a second region, which is formed as a lever housing, and a lever portion for the brake rotary lever. A support wall with a bearing portion, which forms a pivot bearing with a brake rotary lever axis that runs parallel to the brake disc, for the brake rotary lever is arranged between the first region and the second region.

A caliper brake apparatus includes: a guide plate that supports a brake shoe; an anchor pin that supports the guide plate and is provided in a caliper main body to be free to advance and retreat; a piston provided in the caliper main body to be free to advance and retreat; a piston plate that is fixed to the piston and supported by the anchor pin; an elastic membrane that is provided so as to define a pressure chamber in the caliper main body, and that moves the brake shoe via the piston, the piston plate, and the guide plate; and an intermediate member disposed between the piston plate and the guide plate. The intermediate member is interposed between the piston plate and the guide plate such that a gap is formed between the piston plate and the guide plate.