An improved disc brake.

摘要

An improved disc brake is of the type which includes a disc mounted for rotation about an axle. A brake housing is mounted on the axle in alignment with a friction surface of the disc. An axially movable, non-rotatable braking piston has an interior end at least partially mounted within the housing and an external end outwardly of the housing adjacent the friction surface of the disc. Brake actuation means is mounted on the housing. A powershaft is mounted within the housing in a hole in an end thereof in coaxial alingment with the braking piston and is capable of selective rotation by the brake actuation means. The powershaft has worm gear teeth thereon engaged with mating teeth on the interior end of the braking piston to produce axial movement of the braking piston toward and away from the friction surface of the disc directly corresponding to the selective rotation of the powershaft. The improvement includes a powershaft being retained within the housing by a radially extending shoulder portion thereof which overlies an interior surface of the end of the housing. A steel thrust washer is between the shoulder and the interior surface and has a polytetrafluoroethylene material at a surface thereof adjacent the shoulder portion. The thrust washer has an upset portion thereof extending toward the end of the housing. The interior surface is provided a recess for receipt of the upset portion therein to prevent rotation of the thrust washer relative to the end of the housing during selective rotation of the powershaft.