Abstract: A disc brake caliper including a brake piston movably arranged therein. The brake piston is sealed in relation to the brake cylinder by a sealing ring, which is arranged in a circumferential annular groove of the brake cylinder. The sealing ring functions to retract the brake piston in the brake cylinder after a braking operation in order to provide a clearance between a brake shoe and a brake disc. According to the present invention, the annular groove includes a recess, which is arranged in the area of transition between a groove wall and the cylinder surface . The contour line, which defines the cross-section of the recess, starting from the groove wall of the annular groove, passes from a convexly curved portion over into a concavely curved portion. This permits ensuring an unchangingly constant clearance between the brake shoe and the brake disc roughly irrespective of the hydraulic pressure.

Abstract: In a plastic brake piston for a disc brake, the heat conductivity is improved because the brake piston is provided with an insert member made of a metallic material which extends from end to end through the brake piston.

Abstract: A cast-aluminum floating caliper of a floating-caliper spot-type disc brake is reinforced by means of reinforcing elements of a high-tensile material. In accordance with one embodiment of this invention the floating caliper is provided with recesses in an area adjacent the brake disc and the brake shoes. Bolts extend through the recesses in the direct vicinity of the radially outside brake disc edge. Commercially available steel bolts preferably are used. These measures optimize the floating caliper weight, stiffness and manufacturing cost.

Abstract: Various forms of a disc brake hold down spring are disclosed, the spring having two legs disposed in a V-shape and being elastically swingable in respect of each other. In a first form, the legs extend axially and are each formed with a wing loop with one side of the wing being lockable in an undercut opening in the housing while the opposite wing side engages the backplate of at least one brake show. In a second form, the legs extend circumferentially have ends engaging the brake shoes, with a central section received in a brake housing guide opening.