MECHANICAL DUO-SERVO TYPE DRUM BRAKE SYSTEM AND SHOE CENTERING ADJUSTMENT METHOD THEREOF

摘要

PROBLEM TO BE SOLVED: To prevent sliding of a brake shoe on a drum inner peripheral surface as it is oscillated around an elastically contact part with an anchor member at the time of non-braking. ;SOLUTION: When a lever 16 is operated in the counterclockwise direction around a pin 17, brake shoes 3, 4 are extended and opened by the lever 16 and a strut 18 and made contact with an inner periphery of a drum 2, and braking work is carried out. When the lever 16 is released, the brake shoes 3, 4 return to an initial position to make contact with an anchor member 7 and are made in a non-braking state. At this time, return revolution of the lever 16 is limited by a stopper 30, its return revolution critical position is made a position where play of the lever 16 is just eliminated in a state where the brake shoes 3, 4 are centered against the drum 2, and the lever 16 is elastically supported at this position by a spring 23. Consequently, the brake shoes 3, 4 are restrained at this position at the time of non-braking, they are not oscillated around the anchor member 7, and useless sliding with the drum 2 is avoided.;COPYRIGHT: (C)1999,JPO