| 摘要 |
<p>PURPOSE:To hold tensile force operating on a tape invariably constant, by automatically obtaining deficient torque according to the wind diameter of a tape wound around a reel. CONSTITUTION:A voltage control circuit consists of an amplifying circuit 19 which amplifies an electric signal from a magnetic sensor 18 and an F/V converter 20 which converts the signal frequency of it into a voltage. When the magnetic braking force of an electromagnet 15 to a braking rotating disk 11 is constant, takeup torque becomes deficient according to an increase in the wind diameter of a tape, and a reel shaft 3, i.e. a reel turntable 5 decreases in speed corresponding to the deficiency. Therefore, the rotating disk 16 also decreases in speed, so the output of the F/V converter 20 increases in proportion to increase the braking force of the electromagnet 15 to the braking rotating disk 11. Then, the transmitted force between the 1st body A of revolution and 2nd body B of revolution increases to obtain takeup torque suitable for the wind diameter of the tape.</p> |
