GB683838A - A guiding device for kinematograph film - Google Patents

Abstract

683,838. Kinematograph apparatus. WEISSBRODT, J., and BROIDO, J. J. June 6, 1950 [June 10, 1949], No. 14051/50. Class 97 (i). A film guiding device comprises a sprocket and two guiding members arranged at the two sides of the sprocket and parallel to its faces, a V-shaped arcuate groove being formed, in the inner face of each member, concentric with the sprocket axis and at a radius intermediate the root and outside radii of the sprocket teeth. In Figs. 1 and 2 a sprocket disc 4 is carried on a spindle 3 between members 5, 6 grooved at 10 to guide a film with central perforations. The members 5, 6 carry bearings for the sprocket spindle. They are secured to lugs 2 projecting from the wall 1 and form film guides round two parts of the sprocket periphery. They may be resilient and flared outwardly at 12 to assist film threading. In another embodiment guides are formed round one part only of the sprocket periphery and the guide members mounted near a diametrically opposite part. In Fig. 6, grooves are formed at 34 a member 33 secured to the wall 1 and in a member 32 hinged to the member 33 and held in contact with it at 36 by a spring 35. In Fig. 7, one guide member 42, for a film with marginal perforations, is secured to the wall 1, the other, 45, is carried on pillars passing through the first and carrying springs which urge the members towards each other, the movement being limited by spacing members. In a similar embodiment the sprocket disc 4 is centrally disposed for use with a film with central perforations.