| 摘要 |
<p>PURPOSE:To make it possible to change over tape tension values in accordance with a tape traveling state without providing complicated mechanism parts but with a simple constitution. CONSTITUTION:A tension spring 25 for energizing a tension arm 11 to turn is made of a shape memory alloy. An energizing amt. of the tension spring 25 is changed in accordance with the traveling state of a tape 2, for instance, at its normal recording and reproducing time, high speed rewinding time and reverse reproducing time, so that the spring force of the tension spring 25 is changed over in accordance with the traveling state of the tape 2, thus changing over a tape tension value to the optimum.</p> |
