Film feed motion into 4 stages

		1 - the film is drawn down during descent of the claw supporting frame, during which time the gate (whose shape corresponds to one film frame) is masked by a segmentally recessed shutter mounted on the eccentric cam shaft. 2 - at the lower limit of travel, a pin lifts the link carrying the claws, which are thereby extracted from the perforations leaving the film stationary 3 - the claw supporting frame rise " empty ", whilst a film frame is either exposed or projected through the gate unmasked by rotation of the segmentally recessed shutter.
				4 - at the upper limit of travel, the claws are again inserted into the perforations to feed the film by exactly one frame during their descending displacement, whilst the segmentally recessed shutter again masks the gate.