| 摘要 |
<p>PURPOSE:To constitute the title device so that tension of a magnetic tape wound by a prescribed limiter is kept constant by providing a tension arm which is coupled selectively with an end part of a band brake, and a band driving member by which the end part of the band brake is fixed or made movable. CONSTITUTION:At the time of reverse reproducing, an end part 29a of a band brake 29 is in a control cam part 42a of a band driving member 40, therefore, its motion is controlled, and an end part 29b is not only formed as one body with a notch part 27b of a tension arm 27 but also in a non-control cam part 43b of the band driving member 40, therefore, its motion is free. As for driving force of a driving motor, a prescribed torque is transferred to a supply reel base 16, and a magnetic tape 1 is wound to a supply reel without being loosened. Also, since the band brake 29 is wound to the supply reel base 16, the torque which is effective for winding the magnetic tape 1 decreases by a portion of a damping load of the band brake 29. In such a way, a variation of tension of the magnetic tape can be suppressed.</p> |
