| 摘要 |
A movie projector has flickerless forward and reverse film advance at speeds determined by a Geneva intermittent drive mechanism controlled by a rotary timing disc driven at a rate proportional to the film feed rate. Independent servo-driven film supply and takeup reels are each controlled by a swinging arm which senses the length of film stored in the film supply and takeup loops allowing film buildup or excess to discharge to maintain the proper film loop length for gentle handling. Excessive arm movement is minimized by employing a reverse drive pulse of the reel drive motor to dampen oscillations. Photocell sensing of the primary film loops insures smooth film transport without damage to the film.
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