Cam 1 turns about fixed axis A. Disk 2 turns freely about axis A and has guide b for latch 3 which is held by spring 5 in contact with cam 1. Spring 4 is fastened at points C and B to disk 2 and cam 1. When handle a of cam 1 is turned clockwise, spring 4 is stretched, latch 3 is forced toward the centre out of engagement with lug d of the fixed housing and disk 2 is turned by spring 4 clockwise about axis A until latch 3 engages the next lug. Pin e in disk 2 is used to return the disk to its initial position.
$3345$CR,ML$