Lever 1 rotates about fixed axis A. Ratchet wheel 2 rotates about axis A independently of lever 1. Latches 3, actuated by springs 5, consecutively engage ratchet wheel 2 by dropping into slot b of wheel 2. One end of spring 4 is secured at point B of ratchet wheel 2 and the other end at point C of lever 1 . When lever 1 is turned clockwise, its bevelled end disengages latch 3 from wheel 2 which is indexed by spring 4 to the next position. Lug a limits the amount of rotation of ratchet wheel 2.
$136$SL,L$