| 摘要 |
<p>PURPOSE:To fix the rotating phase of both capstans to a set value, by fixing the rotating phase of one capstan, comparing the rotating phase of both the capstans with each other and controlling the rotating phase of another capstan. CONSTITUTION:The rotating phase of capstans 5, 6 is detected by sensing foils 19, 20 and photosensors 21, 22. To a control system at the winding reel, an output of a reference oscillator 26 having a quartz oscillator 25 and a rotating speed detection signal FG1 obtained from an output of a magnetic head 16b of a frequency generator 16b are inputted to a phase comparator 27, and the control of a capstan motor 14 is made through the comparison between a reference voltage Vs1 obtained from a phase error voltage Vphi1 as the output and a detection voltage Vf1 in response to the variation of rotating speed of the capstan 6. in the control system of a supply reel side, the reference oscillator at winding reel side is replaced into a voltage controlled oscillator 35 and the phase control can be made so that the rotating phase of the capstan 5 can be coincident with the rotating phase of the capstan 6.</p> |
