| 摘要 |
A sound movie projector includes, in a serial manner, a first sprocket, an intermittent film advance mechanism for advancing the film on a frame-by-frame basis past a projection gate, a sound recording and/or reproducing head assembly, a film drive roller assembly, and a second sprocket. The difference in film feeding speed at the projection gate and the sound reproducing station is detected by monitoring the length of the film disposed between the film drive roller assembly and the second sprocket by means of a pivotable sensing lever operatively engaged with a portion of the film having a substantially rectiliner configuration under normal conditions, and as a result of such monitoring, the film feeding speed at the film projection gate is appropriately adjusted in a continuous manner utilizing a cone pulley drive system.
|
