Link 4 is connected by turning pair G to connecting rod 2 of four-bar linkage ABCD, and by turning pair F to rocker arm 5. When crank 1 rotates about fixed axis A, the tip of claw a describes a complex connecting-rod curve. At one of the portions of this curve, claw a engages a perforation of the film which it moves. At another portion of the connecting- rod curve, claw a is withdrawn from the perforation.
$779$LW,OC$