Gear 1 rotates about fixed axis F and meshes with gears 2 and 3 which rotate about fixed axes B and E. Links 4 and 5 are connected by turning pairs C and D to gears 2 and 3, and to each other by turning pair K.• When driving gear 1 rotates, the tip of claw A of link 4 describes a complex connecting-rod curve of which a portion is used to insert claw A into a perforation of the film, to advance the film and to withdraw claw A from the perforation.
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