Cassette for roll film - uses central release in bearing surface and cut=out in film tail for latching to prevent tail entering take=up chamber

摘要

The roll-film cassette has a chamber for the feed spool, a second chamber for the take-up and a channel between with the exposure window. The take up chamber (4) has a bearing surface (7) to support the film (1) as it is advanced into the chamber by transport mechanisms engaging the film perforations (1d). To prevent the end of the film being wound into the take-up chamber the film has a cut-out end section (1e) which engages in a recessed central section (8) of the bearing surface (7) and, because the film cut-out has a 'T' formation (1b, 1c), latches into indents (9) in each side of the bearing surface.