| 摘要 |
<p>PURPOSE:To freely adjust the thickness of an air film to be generated between a tape traveling surface of a rotary head drum and a tape and to optimize abutting of the tape against a head by strengthening the tape tension between the drum and a reel at the time of high speed rotation of the drum and weakening it at the time of low speed rotation. CONSTITUTION:When the rotary drum 11 is rotated at high speed, a mode changeover lever 24 of a mode changeover mechanism 20 is oscillated in the direction of a dotted line as shown in the figure to be changed, and the tension of the tape 4 is increased by strengthening the tension force of a tension arm 21 of a tension coil spring 25, so as to thin the thickness of the air film to be generated between individual circumferential surfaces 11a and 14a of their respective drums 11 and 14 of the rotary head drum 10 and the tape 4. Then, when the drum 11 is rotated at low speed, the lever 24 is oscillated in the direction of what is shown by a continuous line to be changed, and the tension force of the arm 21 is diminished and hence the tension of the tape 4 is weakened, thus generating the air film with its appropriate thickness between the outer circumferential surfaces 11a and 14a, so as to improve the abutting of the tape 4 against the head.</p> |
