GB714729A - Improvements in or relating to safety mechanisms of machines adapted for use in cutting sheet material - Google Patents

Abstract

714,729. Machinery safety devices. BRITISH UNITED SHOE MACHINERY CO., Ltd., GARRETT, L., and RIVINGTON, A. A. June 8, 1953 [March 8, 1952], No. 6088/52. Class 80 (4) [Also in Group VIII] In a machine having a plurality of rotating disc knives 126 for cutting sheet material, for example, leather, and a guard member 184 with a transparent window 188 adapted to protect the operator from the rotating knives, interlocking mechanism is arranged between the guard and the driving mechanism for the knives so that the knives cannot rotate until the guard is closed and the guard cannot be opened until the knives are at rest.. The guard 184 is pivoted on a horizontal rod 190, so that it can be raised to give access to the knives, and carries at its right hand pivot an eccentric stud 192 which operates a sheave 194 with a projecting arm 196 guided between a pair of studs 200. The arm 196 co-operates with the end 206 of a plunger 202 the other end 222 of which cooperates with a number of holes 224 in a driving gear 66 of the train driving the knives 126. When the guard is lowered into its guarding position the arm 196 is raised and the plunger end 206 is moved to the left by a spring into a position underneath it so that the guard cannot be opened under such conditions when the machine can be started. To open the guard the plunger 202 must be moved to the right by operating a projecting pin 216 to enter the end 222 into one of the holes 224 in the gear 66. To effect this operation the machine must be stopped and one of the holes 224 aligned with the plunger end 222. The arm 196 can then move downwards and allow the guard 184 to be raised.