| 摘要 |
<p>PURPOSE:To reduce the variance of the access time and to make the high-speed access possible by detecting the time, when the tape speed reaches a prescribed value, to lead out an acceleration error and performing correction in accordance with this acceleration error signal. CONSTITUTION:Reels 2 and 3 around which a magnetic tape 1 is wound are driven by motors 4 and 5, and the tape 1 is transported from the reel 3 to the reel 2 through a tension sensor 6, a magnetic head 7, and a speed tachometer 8. A control circuit 9 generates signals S1 and S2 driving motors 4 and 5. An operating circuit 9a of the circuit 9 generates a maximum acceleration signal S3 and correcting signals S4 and S5, and a switching circuit 9d selects the signal S3 when the tape speed is lower than a target speed, and the circuit 9d selects a speed error signal between the tape speed and the target speed after the tape speed reaches a switching speed. A time counter 9g detects the switching time by the output of a speed detector 9b, and a correcting circuit 9i receives an acceleration signal corresponding to the switching time to store the signal which corrects the acceleration error. The stored value in the circuit 9i is added to signals S3 and S4.</p> |
