GB703741A - Composite spool for photographic films - Google Patents

Abstract

703,741. Photographic film spools. POSSO, P. A. L. Jan. 21, 1952 [April 20, 1951; Dec. 11, 1951], No. 1594/52. Class 98(1) [Also in Group IX] A photographic film spool comprises a cylindrical barrel of plastic material, a film-end retaining .slot extending through the barrel parallel to its axis and a metal flange fixed to each end of the barrel. The spool core may be made by casting or injection moulding of a thermosetting resin, e.g. phenolformaldehyde resin, or a thermoplastic, e.g. cellulose acetate or polystyrene. The core may be cast as an integral unit and may be solid or hollow. If hollow ribs extending across it from the edges of the tapering film end retaining slots may be provided to assist passing the film end through the slots. Alternatively the core may be formed of two similar hollow semi-cylindrical members 11 as shown having half of each of the film retaining slots as 16, pins 13 and receiving sockets 14, a circumferential groove 18 and a winding-key slot 22 at each end, and a rib 17 extending across the core between the film retaining slots. The slots may be of the same length, in which case the halves may be identical. The metal flanges are secured to the core as by knurling of the flange supporting tube, and as shown this operation may also cause the flange to be slightly deformed at points 19 mid-way between the film'slots where depressions are formed in the core members so as to prevent rotation of the flanges on the core.