GB295439A - Improvements relating to machines for the production of transmission chains - Google Patents

Abstract

295,439. Renold, Ltd., H., and Renshaw, A. May 13, 1927 Guards and protectors.-The driving clutch of a machine for assembling roller driving-chains requires the use of both hands of the operator to effect engagement. The spur gear 20, Fig. 26, that drives the main cam shaft 15 is loose thereon and acts through a clutch to provide a stop motion. A spring bolt 135 in the gear engages in a notch 138 in a flanged sleeve keyed to the shaft and can be locked in the disengaged position by a spring dog 191 with a nose engaging a recess in the bolt. Disengagement is effected by a treadle 165, Fig. 23, linked to withdraw a latch 142 that holds down a spring-pressed drawbar 139. On release the drawbar rises and a cam face 196 is projected into the path of a lug on the bolt 135. Both hands of the operator are required to effect re-engagement of the clutch. A hand wheel 152, Fig. 24, is chain geared to the cam shaft for rotating during setting-up, and is interconnected with the safety starting mechanism so that the clutch cannot be engaged when the hand wheel is clutched to the shaft and conversely. When the hand wheel; is pulled outwards to disengage its clutch 154, a spring bolt 159 enters a groove 161 and removes the other end of the bolt from the path of an arm 163 of a bell crank. The other arm 164, Fig. 25, can now be rocked by one hand free from a groove 165 to allow the other hand to pull out a knob 143 linked to the drawbar 139, which is thus pulled down removing the cam 196 from the path of the bolt 135 and engaging a lug 193 to retract the spring dog 191, thus freeing the bolt. The arm 163 now obstructs the rod 159 and prevents reengagement of the hand-wheel clutch. The spring 144 resets its associated parts when the main clutch is again tripped.