Thermal film development apparatus

摘要

A compact thermal developer is mounted in a microfiche reader printer. The developer is a two-stage unit having a pair of roller-heater units located to pass on exposed copy sheet in one direction through succeeding stages in an over-and-under movement to develop the copy and produce a flat hard copy. Each roller-heater unit includes a roller having an outer thin friction coating rotatably supported within an arcuate recess portion of a heater bar. The heater bar and roller are arranged with roller biased toward the heater to grasp the copy sheet. The roller includes a thin aluminum tube supported by heat insulating end members mounted on a shaft with a floating connection to support the tube with a permission relative axial movement to compensate for different coefficients of thermal expansion. A thin silicone rubber coating on the tube establishes positive sheet movement while providing sufficient thermal transmission to present a thermally light background member. The roller-heater units shafts are mounted in plastic end caps supports. The microfiche reader includes a double-faced mirror unit pivotally mounted to transmit the microfiche image onto a front viewing screen or alternately to an exposure frame structure. A small mirror is pivoted from the image path in the alternate position. A copy paper roll is coupled to powered transfer and cutter assembly for moving the paper into and from the exposure frame to the developer.