| 摘要 |
<p>PURPOSE:To obtain a prescribed take-up torque which is free from the effect of ripple, by eliminating the further change of the output of a revolution detecting circuit when said output reaches a prescribed value, and controlling the maximum number of revolutions of a reel motor. CONSTITUTION:A frequency generator 5 generates a signal of the frequency corresponding to the number of revolutions of a reel motor 4. A frequency- voltage (F-V) converting circuit converts the frequency signal given from the generator 5 into the voltage corresponding to the frequeny. The output voltage VOF of the F-V converting circuit is compared with the constant voltage VS through a comparator 7. Then an H-level signal and an L-level signal are delivered in the case of VOF>VS and VOF<=VS respectively. A switch 8 which is controlled by the output of the comparator 7 is turned on when the output of the comparator 7 is set at an H level. While a switch 9 is turned on when the output of the comparator 7 is set at an L level.</p> |
