GB201305A - Improvements in railway vehicle brakes - Google Patents

Abstract

201,305. Cunningham, J., and Dickson & Mann, Ltd. May 17, 1922. Hand actuation; applied by springs; forcetransmitting mechanism.-Relates to improvements in the railway wagon brake mechanism described in Specification 144,793. A spring-influenced lever has a cam-wiper coacting with a cam on one of the actuating shafts so that when the brake is released the main spring 20 will not cause the hand levers to rise suddenly when its crank 13 passes the dead centre. The action of the spring-influenced lever on the cam also assists in the application of the brake. When the brakes are arranged to be actuated by fluid-pressure as well as by hand levers, a lost motion device is provided to prevent the hand levers being moved. The hand levers are arranged close to the wheels so as to be clear of dock hoists &c. Fig. 2 shows an arrangement in which power actuation is not provided for. The hand levers 11 actuate a rock-shaft 8 through rods 58, rockshafts 59, levers 60, 61 and rods 10. The brakes are actuated by the shaft 8 through a lever 13, toggles 14, 15, main spring 20, bar 17, automatic wear compensator 21, and rods 3 as in Specification 144,793. On one of the rock-shafts 59 is mounted a cam 39 contacting with a roller 62 on a lever 38 pivoted at 40, Fig. 6. A spring 41 is arranged to act on the lever 38 so that it opposes the action of the spring 20 when the brakes are being released, and assists the action of the hand levers when the brakes are being applied. Fig. 7 shows a modification in which the cam 39 is mounted on the rock-shaft 8. The crank 13 for operating the main spring 20 is integral with the cam 39. In this modification the toggles 14, 15 may be operated by a connection 56 to a vacuum cylinder piston, or by the hand levers. The toggles are connected by a rod 49 and crank 48 to a rock-shaft 46. A lever 51<a> is pivoted to a crank 54 on the rock-shaft at 53 and has a roller 55 engaging the shaft. When power is employed, the rod 56 turns the lever 51<a> about the point 57 and rocks the shaft to actuate the brakes through the connection 49 to the toggles 14, 15. When the hand-levers are used to rock the shaft 8, the lever 51a is rocked about the point 55 through the main-spring 20 to apply the brakes through the same connections 49, 14, 15. Fig. 8 shows a modified lost-motion device in which the rock-shaft 46 carrying the arm 48 connected with the toggle-operating rod 49 has tappets 51 adapted to be engaged by the pivoted links 47 by which the slide of the spring 20 is suspended.