Plate cam 1 rotates about fixed axis A and is connected by turning pair B to link 4 which, in turn, is connected by turning pair C to slide 2. Slide 2 reciprocates along fixed guides f-f. Rigidly attached to slide 2 is flat spring 3 which contacts the working surface of cam 1 and has claw a. When cam 1 rotates, claw a is inserted into a perforation of the film, advances the film and is withdrawn from the perforation.
$3208$CmL,OC$