An automatic shoe clearance adjustment device for a drum brake

摘要

It is an object of this invention to provide an automatic shoe clearance adjustment device for a drum brake mechanism designed to improve its durability by eliminating a gap, which is caused due to the manufacturing tolerances between the operating end surface of a brake shoe (20) and the extended portion of an adjustment lever (80). To that end, a long hole (81) is formed to extend horizontally in the actuating direction of a service brake actuator (50); and the adjustment lever (80) is pivotally supported via a pin (14) with a capacity of making a rotation relative to the brake shoe (20) and a capacity of making a relative slide in approximately the same direction in which the service brake actuator (50) operates.