| 摘要 |
PURPOSE:To control the travelling speed of a magnetic tape by integrating and constant-multiplying the deviation information between the travelling speed information and the target speed information of the magnetic tape for a speed controlling system of a magnetic tape device of a reel-to-reel system, and generating a virtual error information, and adding it to the deviation information based on the added value. CONSTITUTION:The external fluctuation due to the tension, friction, etc. of a magnetic tape emerges to a deviation Ne, i.e., the output of a comparison arithmetic circuit 15. Such deviation fluctuation is absorbed by an integration circuit 16, and the integrated value is added to the deviation Ne by an adder circuit 18. Therefore the degree of deceleration compared with the target speed of a driving motor 11 is eliminated by an increment of the driving current due to the integrated value. On the contrary, if the motor 11 is accelerated excessively, the degree of acceleration is also eliminated by a decrement of the integrated value. As a result, the tachopulse period N produced by the revolution of the motor 11 is set closer to the target value No. |
