| 摘要 |
A reversible drive transmission particularly suited for use in cassette contained film strip handling apparatus in which a film strip connected at opposite ends to supply and take-up spools is transported between the spools in one direction as for projection and in an opposite direction as in rewinding. A unidirectional input torque is transmitted by the transmission to one or the other of two drive spindles by a shiftable worm carrying shaft extending between and thus on opposite sides of drive spindle connected worm gears. The shaft and worms carried thereon, being driven in one direction, are alternately engaged with a take-up spool driving worm gear or a supply spool driving worm gear depending on the pivotal orientation of the worm carrying shaft. This shaft is supported rotatably on a shift plate pivotally supported from a fixed chassis structure and moved between positions of engagement with the respective spindle worm gears by a logic disc programming overall system operation. A logic disc follower and bracket assembly is pivoted for movement independently of the shift plate but connected therewith by a torsion spring to permit a biased loading of the shaft carrying worms in their respective worm gear engaging positions.
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