Patent GB-1427692-A (GB)
Title: Disc-brakes especially for automobile vehicles
IPC: G21C19/10
Filed: 1974-04-11
Abstract: 1427692 Spot-type disc brakes SOC ANON FRANCAISE DU FERODO 19 Feb 1974 [21 Feb 1973 16 Nov 1973] 7544/74 Heading F2E A disc brake intended for automobile vehicles comprises a fixed support, part of which is substantially parallel to the disc, an hydraulic operating unit arranged to act directly on a first brake shoe to move it perpendicular to the plane of the disc on one side of the disc, a transfer member mounted, for movement perpendicular to the disc plane, on the fixed support and co-operating with the hydraulic unit to move a second brake shoe perpendicular to the disc plane on the other side of the disc, two brackets fixed to the part of the fixed support which is substantially parallel to the disc, each bracket projecting outwardly from the disc and having a flat surface perpendicular to the disc and forming a transfer member stop means, resilient means to urge the transfer member into contact with the stop means, and two laterally-projecting substantially cylindrical lugs carried by the transfer member, the lugs being in line contact with the flat surfaces and having their axes parallel to the plane of the disc. As shown, a slidable transfer member 14 is guided laterally by engagement of flat surfaces 95, 95<SP>1</SP> on it with vertical faces 38, 38<SP>1</SP>, respectively of inwardly-directed projections 37, 37<SP>1</SP> of brackets 33, 33<SP>1</SP>, respectively of a fixed support 10; at the end where it incorporates an hydraulic cylinder 46, the transfer member is restrained radially by engagement of studs 73, 73<SP>1</SP> formed at the ends of a rod 74 with the lower surfaces 44, 44<SP>1</SP> respectively of further brackets 42, 42<SP>1</SP> respectively of fixed support 10. The other end 58 of the transfer member is radially restrained by engagement of a recess 59 with a boss 25 on a brake pad 12B, the pad in turn being radially restrained by engagement of the upper surfaces of support-plate extensions 17, 17<SP>1</SP> with the lower surfaces of the ends of the above-mentioned projections 37<SP>1</SP>, 37 respectively. The directly-actuated brake pad 12A, which is identical in construction with pad 12B, is located in a quadrangular slot 32 in fixed support 10 and is urged radially outwardly by a spring 40 so that its support plate extensions 17, 17<SP>1</SP> engage the lower surfaces of projections 37, 37<SP>1</SP> respectively. The other brake pad 12B is urged against the inside face of end 58 of transfer member 14 by a screw 62 inserted in its boss, the head 70 of the screw being encircled by part of a pre-stressed U-shaped spring 63 whose closed and open ends are accommodated in grooves 72, 72<SP>1</SP> respectively, formed in the outside face of end 58. The transfer member 14 as a whole is urged radially outwardly by two approximately U-shaped springs 83, 83<SP>1</SP>, each having its ends hooked under one of the brackets 33, 33<SP>1</SP> and its supporting zone 84 or 84<SP>1</SP> engaging both the upper side of a bracket and the under side of a projection 91 or 91<SP>1</SP> of the transfer member. In a modified mounting arrangement of the indirectly-actuated pad 12B (Figs. 9, 10, not shown) the screw 62 is omitted; instead the circular central part of U-shaped spring 63 is located in an undercut recess in the centre of boss 25, the screw-threaded bore 27 being omitted.