GB941491A - Adjuster for internal shoe drum brakes - Google Patents

Abstract

941,491. Internal shoe-drum brakes. GIRLING Ltd. Feb. 22, 1962 [Nov. 23, 1960 (2); May 12, 1961], Nos. 40221/60, 40222/60 and 17364/61. Heading F2E. An adjuster for internal shoe-drum brakes in which one end 15, Fig. 1, of a shoe is engaged by an actuator, e.g. piston-cylinder device 13, and the other end of the shoe is in sliding and rocking engagement with a stationary fulcrum or abutment 16 comprises means mounted on a stationary back plate 14 for engagement with a shoe adjacent to its actuated end and acting on the shoe in a direction substantially parallel to the direction in which the shoe end 15 is moved by the actuator. In one embodiment, Figs. 1 and 2 a cam 19 mounted on a spindle 18 bears on an abutment 21 on the back plate and is held in frictional engagement therewith by a spring 23 so that on rotation of the spindle 18 by means of the squared end thereof the engagement of the cam 19 with the abutment 21 causes the spindle 18 to move outwardly along a slot 22 in the back-plate. In another embodiment, Fig. 5, an eccentric pin 36 mounted on a spindle 35 works in a longitudinal slot in a lever pivoted on the back plate and held in engagement therewith by a spring 38, so that on rotation of the shaft 35 by means of the squared end 42 the pin 36 causes the lever to pivot and move the shoe outwardly through the engagement of the cranked end 33 of the lever with a slot 34 in the shoe. In a further embodiment, Fig. 7, a pearshaped lever 51 having a finger 53 abutting a surface 54 on the shoe is moved about a pivot 52 by the engagement of a snail cam 57, mounted on a shaft 55 which has its outer end squared, with a peg 58 on the lever. In a modification the cam is mounted on the shaft outside the backplate and engages a peg fixed thereon.