| 摘要 |
<p>PURPOSE:To ensure an automatic and independent control for both the back tension and the take-up tension, by carrying out a tension control on the basis of the data corresponding to the reciprocal number of the rotational frequency of a reel motor. CONSTITUTION:A frequency generator (FG)241 is connected to a motor 221 mechanically connected to a supplying reel 10 and generates the AC signal (detection signal) Nd1 having a frequency proportional to the rotational speed N1 of the motor 221. This AC signal is supplied to a driving circuit 261. The circuit 261 supplies the drive current IM1 proportional to the number of transmitted signals Nd1 to the motor 221. In the same way, the drive current IM2 is supplied to a take-up reel 16. The currents IM1 and IM2 are adversely proportional to the rotational speeds N1 and N2 of a reel motor. As a result, the tensions T1 and T2 can be held within a constant value by controlling the currents IM1 and M2.</p> |
