| 摘要 |
<p>PURPOSE:To constitute a stable control system by providing the first arithmetic processing means that detects a reference value, supply reel (S reel) rotation period TS, takeup reel (T reel) rotation period TT and calculates the difference from the sum of respective squares (T<2>S+T<2>T) and the second arithmetic processing means that controls the gain of a variable gain means. CONSTITUTION:By making the sum of square of rotation period of S and T reels constant, tape carrying speed V becomes constant. Outputs of counters 7S, 7T obtain digital values NS, NT corresponding to the rotation period of S, T reels, and a square arithmetic units 8S, 8T calculate N<2>S, N<2>T respectively, and output to an adder 9. A value obtained by subtracting (N<2>S+N<2>T) from the reference value Nref by a subtracter 11 is outputted to a D/A converter 12. A gain regulator 13 is for operating a control system stably according to the change of reel inertia and the change of rotational speed of the T reel to be controlled, and the gain is controlled by a value NT related to the diameter of the T reel. An Err signal is inputted to a T reel driving circuit 15 through a filter 14 for phase compensation, and the rotational speed of the T reel is controlled.</p> |
