GB1458820A - Film cassettes - Google Patents

Abstract

1458820 Light-tight film cassette CIBAGEIGY AG 18 April 1974 [16 May 1973] 23350/73 Heading B8M A light proof film cassette comprises a spool 12 in a casing comprising two semi-cylindrical body members 1, 8 of opaque plastic and having end walls with semicircular openings to receive the spool hub, there being a flange 18 on each end of the spool to abut the end wall formed by the two members, the bottom and side edges of the members having overlapping extensions (13, 14 and 15, 16, respectively, Figs. 1, 2, not shown) or interfitting tongues and grooves to light proof the cassette, the members 1, 8 having a lip 2, 9 respectively co-operating to form an exit slot for the film, the end walls of the lips having overlapping extensions or interfitting tongues and grooves, each body member having at each end a semi-cylindrical axial extension of the body on which are present two lugs 3, 4 and 10, 11 respectively, one at each end of the extension, each lug co-acting with a corresponding lug on the other body member to form four pairs of locking means which hold the cassette together. Specification 1,458,819 shows the same cassette. Its claims are directed to the light labyrinth formed by the lips, the cylindrical wall on member 1 and the extension 20 of lip 9 on member 8. The cassette is assembled by bringing rounded lugs 4, 11 together their rounded shape permitting sufficient relative movement to snap lugs 3, 10 together. As shown side extension (14) of member 1 overlaps side extension 13 on member 8 and angled bottom face (15) of member 8 fits over angled face (16) of member 1. The members are moulded from polystyrene, polypropylene, acrylonitrile-butadiene-styrene copolymer, cellulose nitrate or cellulose acetate. The material contains 5% polytetrafluoroethylene to reduce friction and carbon black or titanium oxide plus dye to render it opaque.