GB910163A - Improvements in central buffing and draft gear - Google Patents

Abstract

910,163. Central buffing and draw gear; rubber springs. AVON INDIA RUBBER CO. Ltd. May 26, 1960 [May 26, 1959], No. 17956/59. Classes 103(5) and 108(3). A central buffing and draw gear comprises a shell member 12 attached to a forward follower 13 and telescopically movable over a shell 10 forming a hydraulic fluid reservoir welded to a rear follower 2, a casing member 1 welded to the follower 2 and fixed to an intermediate follower 3 having an annular projection 5, springs 6, 14, and a spindle 15 which may co-operate with a separate piston 7 movable in hydraulic fluid in the casing 1. When a load is applied through a yoke to the follower 13, assembly shear pins 16 are broken, and the spring 14 is alone compressed until the follower 13 abuts the end of the spindle 15, whereafter the springs 6, 14 and the hydraulic unit operate in parallel. In a modification the spindle 15 in Fig. 1 may be extended to contact the follower 13 so that the springs and hydraulic unit operate always in parallel. The spring 6 provides a recoil force, but if pressure on the forward side of the piston 7 exerts a force greater than the force of the spring 6 then the piston will move off the spindle and allow fluid to flow through the duct 18 in the manner of a safety valve, thus preventing excess pressure being exerted on the seals 17. The spring 6 is made up of four units each consisting of a metal plate 20 having pads of rubber 21, 22 on each side united through holes in the plate, and separating plates 23 are provided. The spring 14 is made up of six units with annular concentric rubber rings on each side. Specification 830,459 is referred to.