GB191307625A - Improvements in Automatic Brake Slack Adjusters or Slack Gatherers for the Brake Systems of Railway Carriages, Railway Wagons and the like. - Google Patents

Abstract

7625. Birmingham Railway Carriage and Wagon Co., and Hill, E. O. April 1. [Cognate Application, 12,674/13.] Compensating for wear.-In slack-adjusting apparatus for the brake mechanism of tramcars, railway carriages, wagons, &c., a ratchet bar A, provided with a slot 4 sliding on a guide 5 carried by a fixed bracket B, is connected at 3 to the brake blocks and is engaged by a pawl C pivoted on a pin 9, which is connected to the pull-rod E and slides in slots 16 in the bracket B. A second pawl D, engaging the ratchet, is pivoted on a pin 20 sliding in the slot 4. The pawls are provided respectively with flanges 19, 25 adapted to contact with stops 7, 6 formed on the bracket B. The rod E is subjected to a pull to apply the brakes, and, when sufficient wear occurs, the pawl D comes against a fixed stop 31 and takes up a tooth on the ratchet; and, during release of the brakes, the pawl C similarly takes up a tooth. The flange 25 of the pawl D is arranged in relation to the bracket B so as to be prevented from rising out of engagement with the ratchet until the pawl reaches the stop 31, in which position the flange 25 rises into an inclined cutaway portion 26, Fig. 10, on the bracket. In a modification, the flange 25 is constructed with an extension which normally contacts with the underside of the stop 6, but moves clear thereof when the pawl reaches the stop 31 to allow the pawl to rise. The ratchet bar A may have teeth at the underside engaged by a second set of pawls. The pawls are constructed of pairs of side plates 12, 22 connected by intermediate blocks 14, 32, which are formed with teeth 15, 23 and made heavy to ensure engagement of the pawls with the rack.