Patent GB-1130549-A (GB)
Title: Improvements in or relating to disc brakes
IPC: F16D55/00
Filed: 1966-01-20
Abstract: 1,130,549. Disc brakes. SOC. ANON. D.B.A. 20 Jan., 1966 [21 Jan., 1965; 23 March, 1965; 30 July, 1965], No. 2711/66. Heading F2E. In a disc brake of the floating-caliper type, the pads and the floating stirrup 15 are independently guided with respect to a fixed frame 2 of U-shape straddling the disc 1, the pads being guided and retained against radially outward movement by edges 7, and the floating stirrup being guided and retained by key members 20 interposed between the stirrup and the frame, a leaf spring 22 urging the stirrup radially outwardly to lock the key members in position on the frame, whereby dismantling and re-assembly can be readily effected by manually depressing the stirrup radially inwardly against the spring action to free the key members. In the embodiment of Fig. 1, the edges 7 and the corresponding pad edges are inclined, and a pair of leaf springs 13 urge the pads radially outwardly to contact the edges 7. The stirrup, which has a central opening to reduce its weight, is formed with projections 18 presenting inclined faces 19 which engage the key members 20, the latter being arranged in recesses 23, 24 and being formed with a tenon (21, Fig. 2, not shown) adapted to engage between the limbs of the frame to lock them in position. In the embodiment of Fig. 4 (not shown) key members (27) engage inclined slots (25) in the saddle (15) instead of the projections (18), which are omitted. Also in this embodiment, the inclined edges (7) are replaced by vertical edges (28), projecting portions (30) extending towards one another at the open ends of the pad recesses to retain the pads against radially outward movement. Modified leaf springs (32) which are slotted to engage the bottoms of the associated pad recesses, replace the springs 13. In the embodiment of Fig. 7 (not shown) the pad recesses are replaced by apertures each divided by a wall (38) from the recesses which accommodate the key members (26) and the stirrup. This embodiment is otherwise similar to that just described. In a further embodiment (Figs. 8-12, not shown) the stirrup is guided as in the embodiment of Fig. 1, but the pads are guided similarly to those in the embodiment of Fig. 4 (not shown). In addition, each of the pads is provided with a radial groove (144) in the middle of its length and its backing plate has a tenon (146) adapted to engage a groove in the piston of the operating cylinder (in the case of the directly applied pad) to prevent rotation of the piston which would be necessary when the piston is associated with certain types of automatic adjuster (not specified). The frame is reinforced in this embodiment by a riveted plate (113) and by a flange (115). A modified key member suitable for use in the embodiment just described (Figs. 13-15, not shown) has inclined faces (174) engageable with the stirrup recesses. Also there is provided, in addition to the tenon (172), a flange (176) on one side, and a hole (178) for a retaining pin (180), which together ensure that accidental withdrawal of the key member is prevented. This is further ensured by a leaf spring (184) adapted to engage the inclined face of the stirrup extension which is engaged by the key member. The diagrammatic illustration of Fig. 16 (not shown) is intended to show that, by using pads provided with extensions less than the full height of the pad and engaged with overlying frame projections (as in the above described embodiments of Figs. 4 and 8, not shown) the forces tending to open up the pad recesses during heavy braking are reduced. The further embodiment of Fig. 17 (not shown), uses key members (273) of angular cove-like section, retained by pins (280), whereby a tenon is unnecessary. Also in this embodiment, the leaf spring (266) acting on the stirrup is formed with tongues (281) which engage abutments (229) on the pad backing plates to restrict circumferential movement of the springs. A still further embodiment (Figs. 20 and 21, not shown) is similar to that of Fig. 1, except that the stirrup has a detachable cylinder (339) secured to axially projecting flanges of the stirrup by bolts (348). Also, reinforcing plates (349) are used to guide the pads. 1,130,550. Disc brakes. SOC. ANON. D.B.A. 20 Jan., 1966 [21 Jan., 1965; 23 March, 1965; 30 July, 1965], No. 14535/68. Divided out of 1,130,549. Heading F2E. The subject matter is the same as that portion of the subject matter of the parent Specification which is disclosed in Figs. 8-12 of the drawings accompanying the latter, the claims being directed to a friction pad for a spot type disc brake having a carrier plate formed so as to provide lateral projections of rectangular shape at each end of the portion which corresponds to the shape of the pad, these projections defining the anchoring edges of the pad on a fixed support and being located such that the centre of the rectangular portion of the pad between the projections is between the centre of the pad and its base.