INLET GUIDE STRUCTURE FOR ROLLING LOOP FILM TRANSPORT ANISM

摘要

Inlet guide structure is provided having complementary outer and inner guides which are adapted to receive film from a drive sprocket of a rolling loop film transport mechanism and to guide the film inwardly towards a path defined between the stator and the rotor of such a mechanism. The outer and inner guides have respective pairs of co-operating side faces for guiding side portions of the film remote from a centre portion of the film. The side faces of the outer guide define a rounded nose portion intermediate ends of these side faces, and the side faces of the inner guide define a depression corresponding to the nose portion so that when in use the guides combine to form a passage which guides the film by contact between the side faces and the side portions of the film. The nose portion and depression combine to cause the passing film to define a transverse curve about the nose portion, and the passage restrains the film to leave the passage at an acute angle to said path between the stator and the rotor so that an impact by the rotor will start a loop to grow and any tendency for creation of a rigidifying longitudinal bend will be significantly limited because the film is rigidified transversely by the transverse curve about said nose portion.