Cassette and drive system for microfiche recording system with traveling film head

摘要

An intermediate film strip cassette and associated drive apparatus provide a film dispensing system for positioning of intermediate images carried on the filmstrip as it is moved from an exposure station to a final station for image transfer to an archival microfiche film under conditions where bowing stresses are applied to the intermediate film at one or more of the processing stations. The cassette performs both supply and takeup functions, and requires no threading by the operator during film replacement. A combination of external locking drive motors engaging the cassette elements and a compliantly loaded takeup idler within the cassette provides a compliant tension to the film element extended into an imaging area, and suppresses erratic film shifts at the various stations while allowing adequate protection against film breakage arising from said bowing. A sensor associated with the tensioning idler aborts the replication process in case of film breakage, and thus guards against loss of archival records from such causes. In one version a system of film markings and external sensors serves to govern film advance and detect and warn of any incipient end-of-film condition. In an alternative version an encoder wheel sensing system driven by film passage over a transport roller serves to govern film advance.