| 摘要 |
A cine camera for taking talking pictures comprises a film-feeding mechanism which includes a driven capstan and a pinch roller normally spaced therefrom to facilitate insertion of a section of film therebetween when the camera casing is loaded with a sound-film cassette. A sensor, upon detecting the presence of such cassette in a receiving chamber of the casing, causes the pinch roller to move closer to the capstan, either via a mechanical linkage or by deactivating a detent normally blocking a displacement of the pinch roller under spring pressure. This displacement under the control of the sensor may establish a standby position, with the pinch roller still separated from the capstan by a clearance wider than the film thickness, that clearance being subsequently reduced by the operation of a trigger, a mode-selector switch or the like to clamp the film between pinch roller and capstan. The biasing pressure acting upon the pinch roller may be supplied by a toggle spring which is rendered effective by a prestressing mechanism upon closure of a lid for the cassette-receiving chamber.
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