GB314607A - Improvements in braking mechanism - Google Patents

Abstract

314,607. Girling, A. H. G., April 5, 1928. Blocks acting on drums; band; force-transmitting mechanism; compensating for wear; indicators, applications of; personal actuation. - Expanding means for operating brakes comprises a wedge movable endwise and centrally placed between inclined surfaces parallel to its own inclined surfaces, each pair of parallel surfaces being separated by an antifriction device such as a roller or ball free to roll up both parallel surfaces. The axis of the wedge may be parallel at right-angles or at any other angle to the plane of the braking element. The angles of the parallel surfaces to the wedge axis may differ in order to obtain different rates of movement of the two ends of the brake element. The inclined surfaces of the braking element mav be adjustable. The rollers may lie in grooves or be arranged to surmount steps on the inclined planes to give a quick initial movement. The rollers B, Fig. 11, may be located in the " off " position, to which the wedge A is returned by a spring E by stops on the inclined surfaces. The inclined surfaces on the braking elements may be formed of cones on the end of plugs screwed into the braking elements for adjustment purposes or the plugs H, Fig. 11, may be inclined. In Fig. 10 the inclined members H are adjusted by rotation of nuts J. For this purpose an outside hand-wheel L may beused. A pointer M facilitates adjustment. In Fig. 11 the plugs H are formed with bevel teeth which mesh with an adjuster L. When the brake is correctly adjusted the end of the wedge A is flush with the surface N when the brake is off and a groove M is flush with the surface N when the brake is on. The rod Q operating the wedge A is connected therewith by a pivot R, which is arranged coaxial with the steering pivot in the case of a steering wheel. The parts are contained in a casing T. The reaction of the pull on the rod Q is taken by abutments F and the casing is normally held frictionally against abutments F<3> by springs S, so that the casing may locate itself between the ends of the braking elements. A spring is shown adapted to be hooked to the brake pedal in order to apply the brakes during adjustment.