| 摘要 |
<p>PURPOSE:To detect tension stably and accurately in a wide range without a complicated, mechanical and electric adjustment. CONSTITUTION:One end side of a tension arm 1 is held by a rotary shaft 7 freely rotatably and given a specified rotative force around the rotary shaft 7 by a pulling spring 3. A tension post 2 is erected on the other end side of the tension arm 1 and displaced against the rotative force receiving the tension of a magnetic tape 4. A semicircular flat plate 5 is arranged so as to be rotated around the rotary shaft 7 integrally with the tension arm 1 and a semicircular flat plate 6 is fixedly arranged opposed to the flat plate 5 and a variable condensor is formed by the flat plates 5 and 6. In accordance with the displacement of the tension post 2, the tension arm 1 is rotated around the rotary shaft 7 and the capacitance of the variable condensor is changed. The tape tension is detected by detecting the change of this capacitance.</p> |
