GB1315996A - Brake-actuating devices - Google Patents

Abstract

1315996 Brake slave cylinders; adjusting for wear KNORR-BREMSE GmbH 12 Aug 1970 [12 Aug 1969] 38934/70 Headings F2E and F2F A brake cylinder having a piston 2 actuable by fluid pressure (specifically hydraulic pressure) to apply a disc or block brake of a rail vehicle, also comprises a device to adjust the position of the piston 2 to compensate for brake lining wear which device comprises a non-rotatable screw-threaded spindle 4 and an adjusting nut 5 threaded thereon; the piston 2 and nut 5 are non-rotatably engageable by friction or toothed surfaces 2<SP>1</SP>, 5<SP>1</SP> and pressure fluid introduced through a connection 14 causes movement of the nut and the piston 2 to the left to apply the brake until a preset clearance s is taken up, whereupon the surfaces 2<SP>1</SP>, 51 will be disengaged and the nut 5 is rotated under the loading of a spring 7 along the spindle 4. Upon release of the fluid pressure the piston 2 and the nut 5 will again be coupled through surfaces 5<SP>1</SP>, 21 and will be moved to the right by a return spring (not shown) a distance s during which movement the advanced position of the nut 5 relative to the spindle 4 is retained. As shown in Fig. 1, the spring 7 acts on the nut 5 via a ball-bearing 6. The brake may also be applied manually by a lever 12 which acts on a shaft end 9 of the spindle 4 to move the spindle 4, the nut 5 and the piston 2 to the left; on releasing the lever 12 the elements are returned to their initial positions without adjustment. As shown in Fig. 2 a two-part adjusting nut 28 comprises a port 29 and a sleeve 31 and in pressure actuation the sleeve 31 and a piston 16 are moved to the left through a distance e until a ball-bearing 34 acted on by a preloaded spring 36 abuts a flange 30 of the port 29. The port 29 and sleeve 31, which are relatively non-rotatable by engagement of pin 39 in an aperture 38 of the sleeve 31, are then rotatable on the spindle 18 to take up brake lining wear. The brake is also applicable manually by a lever arm 43<SP>1</SP> of a hand lever 43 which acts on the square end 29 of spindle 18.