| 摘要 |
PURPOSE:To execute a stable control extending from low speed to high speed by controlling the driving speed of a reel base through a control circuit, by the output of a speed detector provided with two converting elements for detecting the low speed and the high speed of a tape. CONSTITUTION:A speed detector 33 is provided with a first converting element 33a for detecting low speed running speed, consisting of a minute slit pattern 23a and a first photocoupler, and a second converting element 33b for detecting a high speed running speed, having a rough slit pattern. Their outputs are switched selectively by an electric switch 32b, and control the speed of one of driving devices 26, 28 of a winding reel base or a supply reel base through a control circuit 31. Accordingly, when a tape runs at low speed, a detection having high resolution can be executed, and when it runs at high speed, a wide and stable control extending from low speed to high speed can be executed without generating an output drop caused by the responsiveness.
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