GB803524A - Improvements in or relating to mechanical servo disc brakes - Google Patents

Abstract

803,524. Disc brakes. SHEEPBRIDGE ENGINEERING Ltd., and BROWN, T. Sept. 28, 1956 [June 30, 1955], No. 18984/55. Class 103 (1). In a mechanical servo disc brake, friction pads 20 and 21 carried by backing plates 22 and 23, respectively, are housed in a fixed hollow casing 15 (Fig. 1) and are adapted to engage frictionally the radially extending sides of a rotatable, axially slidable brake disc 10 and be carried round by the disc for a limited distance; servo means in the form of balls 27, 46 operating in conical or like recesses 24, 26 and 39, 40, respectively, being provided between backing plates 22 and 23 and the sides of fixed hollow casing 15 for imparting additional axial pressure to the pads. Springs 9 are provided to move pads out of frictional contact with the disc 10 when the brake is released. Rotation of shank 30 by operating lever 8 forces balls 7 to ride up the sides of conical recesses 32, 34 imparting movement to member 29 which in its turn imparts movement to the backing plate 22 and friction pads 20. The disc 10 moves axially so as to press it against pads 21. The two pairs of pads tend to rotate with .the disc causing balls 27 and 46 to roll up conical sides of recesses causing further axial movement of the pads and a servo-action results. Adjustment for wear of the pads may be made by rotation of nut 44. In a further embodiment illustrated in Fig. 5, only one friction pad is disposed on opposite sides of the brake disc 10. Actuation of operating cable 63 causes C-shaped lever arm 59 to pivot about pin 58 and force backing plate 22 and associated pad 20 against the axially slidable disc 10 to bring the latter into frictional engagement with pad 21, associated with backing plate 23 mounted on fixed wall 42 of housing. Servo means similar to those described with reference to Fig. 1 are inserted between the limb 25 and plug 55 associated with fixed wall 42 of the housing.