Patent GB-711086-A (GB)
Title: Disc brakes for vehicles
IPC: F16D55/00
Filed: 1952-03-06
Abstract: 711,086. Disc brakes. DUNLOP RUBBER CO., Ltd., and BUTLER, H. J. Feb, 17, 1953 [March 6, 1952], No. 5819/52. Class 103(1) A fluid pressure operated disc brake for vehicles comprises a rotatable shaft, two or more brake discs axially slidable on and rotatable by the shaft, non-rotatable bridge - pieces extending axially adjacent the outer peripheries of the said discs, a pair of transverse members connecting corresponding ends of the bridge-pieces, one on each side of the assembly of discs, axiallyaligned friction pads secured to both ends of the transverse members to frictionally engage one side of an adjacent disc. a non-rotatable guide member located between each pair of adjacent discs and axially-aligned with the friction paids. a pair of friction pads axially-slidable in each guide member to frictionally engage the adjacent sides of the discs and a fluid pressure operated mechanism located between each pair of slidable friction pads to effect frictional engagement between the pads and the discs. The brake, particularly for a tank or other heavy vehicle comprises a pair of identical axially-spaced discs 1 and 2 which are mounted on a driving shaft 4 so that they are rotatable with the shaft and axially slidable along splines 5. The disc 1 is situated adjacent to a steel plate 6 which is a rigid and integral part of the vehicle structure. Two diametrically-opposed, shaped bridge-pieces 7 are secured to and extend axially from the plate 6 and extend axially adjacent the outer periphery of the discs 1 and 2 and are secured at their free ends to a beam 9 to form a box-like structure. Diametrically-opposed segmental friction pads 12 and 13 are secured to the beam 9 and the plate 6 respectively to frictionally engage the adjacent sides of the respective discs 2 and 1. Provided in the centre of each of the bridge-pieces 7 is a closure member 14 which has dependent from its inner side a segmental guidemember 18 which extends radially inwardly of the bridge-piece 7. The guide-member is provided with a segmental shaped hole extending axially therethrough within which is housed an open-ended cylinder 19. A piston 20 is slidably and fluid-tightly fitted in the cylinder 19 and sealed against the ingress of dirt &c. and is provided integrally with a stem 21 in which a backing plate 22 is rockably seated. A similar backing plate 26 is rockably seated at the base of the cylinder and to the planer face of each backing plate is fitted a segmental pad 24, 27. In operation, the discs 1 and 2 rotate with the driving shaft 4, the remainder of the brake assembly being non-rotatable and on applying braking pressure, fluid is forced from a master cylinder or the like to the annular gap 29 forcing apart the piston 20 and the cylinder 19 and moving the friction pads 27, 24 into frictional contact with the adjacent sides of discs 1 and 2 respectively. The discs are thus caused to move axially along the splines 5 until the rotating discs are frictionally engaged between the non- rotating friction pads to brake the driving shaft 4. To assist cooling, a stream of compressed air may be played on the parts of the discs projecting exterior of the box-structure.