GB249771A - Improvements relating to means for actuating the brake shoes of vehicle brake mechanism - Google Patents

Abstract

249,771. Clark, D'A. M., (Bendix Brake Co.). April 3, 1925. Blocks acting on drums.-The cam or equivalent expanding member for the shoes of an internal expanding brake for vehicle wheels is carried by a support which is normally held frictionally in a fixed position, but is shiftable when the brakes are applied, in order to permit the expanding member to centre itself with respect to the shoes. As shown in Figs. 1 and 2, the shaft of the cam 38 is mounted in a support 46 having laterally-extending wings on which sleeves 48 are carried by means of bolts 50. The sleeves pass through slots 54 near the ends of the brake shoes, whilst the bolts 50 pass through elongated slots 51 in the drum cover plate and carry a plate 52 at their inner ends which serves to confine the brake shoes laterally. If the nuts holding the bolts 50 are not too tightly screwed up, the cam 38 is able to centre itself in a brake application by forcing the bearing 46 laterally. As shown in Fig. 1, the brake may comprise a shoe 20 bifurcated at its lower end and pivoted at 32, a shoe 22 pivoted at 34, and a shoe 24 freely jointed to the shoe 22 at 36. The pivots 32, 34 pass through large slots in the shoes 22, 20 respectively. The cam 38 has a short bottom lobe to engage the shoe 20 and a longer upper lobe to engage the shoe 24, thus providing for the greater movement of the latter shoe in a brake application.