GB829866A - Improvements in or relating to disc brakes - Google Patents

Abstract

829,866. Disc brakes. MINISTER OF SUPPLY. April 3, 1956 [Jan. 3, 1955], No. 137/55. Class 103 (1). In a spot-type disc brake having a self-servo action, upon actuation of the hydraulic braking mechanism the plunger 16 is moved by piston 17 towards the disc 1 and this movement is transmitted through rollers 14 and arms 9a, 11a, of bell-crank levers 9, 11 respectively acting as thrust members on brake plate 6 to force brake pad 4 into frictional engagement with axially slidable brake disc 1 to move the latter into frictional engagement with brake pad 3 carried on fixed brake plate 5. If the vehicle is moving forwardly when the braking effort is applied, application of the brake pads to the brake disc will cause the pad 4 to move either tangentially to the disc 1 to move the arm 9b which engages the leading edges of the pad 4 and the plate 6. The bell-crank lever is thus turned about its pivot and the nose of its other arm 9a is pressed against the face of the brakeplate 6 remote from the pad, in a direction perpendicular to such face and to the plane of the rotation of the brake disc to augment the force normally applied to the brake pads. Should the braking effort be applied when the vehicle is moving rearwardly, the bell-crank lever 11 which is adapted to engage the trailing edge of the brake pad 4 and plate 6 will be brought into operation instead of the bellcrank lever 9 to augment the force applied to the brake pad 4. The brake disc may be fixedly mounted on its shaft and the brake pads both moved towards the brake disc. The brake pads and their plates may then be carried on a calliper frame and each brake pad may have associated therewith two bell-crank levers to augment the force normally applied thereto. The bell-crank lever may be actuated mechanically instead of hydraulically as described above. Reference has been directed by the Comptroller to Specification 730,053.