Automatic braking gap adjustor system for mechanical type drum brake

摘要

An automatic braking gap adjustor system for mechanical type drum brakes, including a cam member for expanding brake shoes by turning of a brake arm, a cam collar axially slidingly fitted into the cam member, the cam collar abutting onto the free ends of shoe webs, an adjusting bolt axially and threadedly inserted through the cam member to move the cam collar, an adjusting gear disposed so as to be rotatable in unison with the adjusting bolt, and a stopper lever engaged with the adjusting gear in such a manner that the gear is kept from turning in the actuation direction of the cam member, whereby, when the abrasion of the linings reaches a predetermined value, the adjusting lever is engaged in another place with the adjusting gear for adjustment, and further a support pin extending parallel to the cam member, to which is attached the stopper lever in such a manner that it is movable in the actuation direction of the cam member, and a spring member whereby the stopper lever is biased in the counter-actuation direction of the cam member.