| 摘要 |
<p>PURPOSE: To prevent a tape from slacking during running by switching an accelerating/decelerating speed when a slack of the tape is detected and moderating a change of the speed. CONSTITUTION: The rotation periods of reels 4, 9 are detected by rotation period-detecting means 13, 14, respectively, which are input to a tape slack- detecting means 16. The presence/absence of an abnormal change of cycles is detected by turning both data in a cyclic form. An acceleration/deceleration speed-controlling means 17 controls a tape speed-controlling means 15 by a speed switch signal from a terminal T2 so that a tape speed keeps a target speed. if a slack signal is supplied from the tape slack-detecting means 16, the controlling means 17 switches the acceleration/deceleration speed and supplies the speed together with data of the tape speed from a tape speed-detecting means 18 to the tape speed-controlling means 15, thereby controlling a motor 10 to make speeds of both reels agree. In this manner, the speed is changed moderately when the tape slack is detected. The tape slack generated when the tape speed is changed is prevented.</p> |
