| 摘要 |
<p>PURPOSE:To prevent the slacking of a tape unnecessarily when a tension controller is released and to smoothly change-over the tape to a reverse reproducing mode by providing separately a tension detecting means and a braking force variable means to make variable the pressuring force of a rotary member. CONSTITUTION:When a magnetic recording and reproducing device is changed over to a recording reproducing mode, a tape 1 is driven in the A direction of an arrow, then, the tape tension occurring at the 1 is detected by a tension post 2, the pressuring force to the reel base braking part 4 of a braking belt 5 is made variable by the balance of the force turning a tension arm 10 in the clockwise direction and a tension spring 9. The tape tension is made constant. Next, when the device is changed over to a reverse reproducing mode and a tension arm 11 is forcibly released from the external part, the pressuring force to the reel base braking part 4 of the braking belt 5 is made variable, and a large driving source is not necessary to rotate a supplying reel base. In such a case, the tension post 2 is abutted to the tape 1 by a subtension spring 12.</p> |
