GB671324A - Improvements in or relating to brakes for vehicles - Google Patents

Abstract

671,324. Internal shoe-drum brakes. GIRLING, Ltd. Jan. 22, 1949 [Dec. 23, 1947], No. 33898/47. Class 103 (i). In a brake of the type, as shown in Fig. 1, in which opposed shoes 30, 31 are adapted to rock or slide at one end on an anchorage or abutment 38 and an expander 35 is arranged between the other ends and is adapted to spread the shoes so as to engage a rotatable drum 32, the expander 35 and anchorage means or adjuster 38, are mounted on a frame member 40 which is connected by pivoted links 41, 42 to a flange 43 on the fixed axle of the wheel carrying the brake drum, so that the frame and shoe assembly has a limited freedom of movement to swing in a direction substantially parallel to the axis of the tappets 33, 34 of the expander, the arrangement being that the links 41, 42 extend in opposite directions from their connections to the fixed axle flange 43. There are pairs of such links 41 and 42, one on each side of the frame member 40, clearance holes or slots 48 being provided therein around the pivot pin 46 with the fixed flange 43 to allow the lateral swinging movement. In the arrangement of Figs. 5 and 6 in which the brake drum is not shown, the floating frame member, on which the shoes and actuator are mounted, is a flanged plate member 82, which is pivoted to the fixed flange 83 by single links 88, 89, a hair spring 90 co-operating with a lug 91 providing for shoe centralization. Figures 8 and 9 show a brake assembly, according to the shoes, the cam mounting being designed to allow for the diametrical shifting of the frame 124. The cam block 131 turns within a ring 132 rigid with the frame 124 and is connected by a pin 130 with a U-shaped member 129 rigid with the operating shaft 127. The hole in the cam block 131 through which passes the pin 130 is provided with sufficient clearance to permit the transverse movement of the assembly after the shoes have been applied to the drum.