| 摘要 |
1,065,642. Disc brakes. GIRLING Ltd. June 4, 1964 [June 12, 1963], No. 23363/63. Heading F2E. In a disc brake of the kind having a floating caliper including actuating means for applying one pad to one face of a disc directly and another pad to the opposite face of the disc by reaction, a small area of contact is provided between at least one pad or its backing plate and the actuating member or caliper housing, the size of this area being so chosen in relation to the area within which the centre of pressure of the applying force lies that pivoting of the pad does not normally occur, whereby it is normally constrained to follow a predetermined wear path, but pivoting of the pad can occur to accommodate deflections of the disc. In one embodiment, Figs. 3 and 4, the pad 19 which is directly actuated by an hydraulic piston via rocking lever 23 can pivot freely about a partspherical projection on the end of a plunger 30, but the other pad 15 is normally constrained by a flat surface 17 of a projection on the caliper housing 18 to follow a predetermined wear path, the area of surface 17 however being sufficiently small to permit pivoting of the pad 15 upon deflection of the disc caused by changes in axle loading, endwise axle movement or thermal coning of the disc. The backing plate 16 of the pad 15 may be provided with the projection instead of the caliper housing, and such projection may be in the form of four protuberances arranged at the corners of a rectangle, Fig. 5 (not shown). In either case the dimensions of the area of contact are preferably between 15 and 25% of the circumferential and radial dimensions of the backing plate, the former dimension constituting the major axis of the area. The surface 17 may be concave instead of flat. The pads are guided for axial movement by removable pins 35 engaging grooves 36, 37 in the housing and backing plates respectively, a spring clip 38 engaging grooves in the pins 35 to lock them in place so that on removal of the clip the pins can be withdrawn to allow removal of the pads in a radial direction. In the embodiment of Figs. 6 and 7 (not shown), the directly actuated pad 53 is guided by removable bars 55 and the other pad 59 by projections 63 on the housing at either side of the rectangular contact area 61, this arrangement also allowing removal of the pads radially. In both embodiments an alternative applying means is provided comprising a cam 34 acting on the rocking lever 23 and rotatable by an external lever 33, Fig. 5, or 58, Fig. 6. |
