| 摘要 |
PURPOSE:To make the cost less and the size of the demagnetizer smaller, by placing the 2nd electromagnets producing the specified rotating magnetic field between the magnetic poles opposed to the electromagnets, in a given interval. CONSTITUTION:The both sides 50a, 50b of the cassete tape 50 placed on the belt conveyor 40 are demagnetized with the AC magnetic field H1 while it passes between the electromagnets 10. Next, when the tape 50 passes through the electromagnets 20, the rotating magnetic field H2 is fed to the front and rear parts 50c, 50d of the tape 50, and this magnetic field H2 is fed so that the orientation processing directions B, B' of tape can be rotated. Accordingly, when this rotating magnetic field H2 is applied, the parts of 50c and 50d can easily be demagnetized. Thus, the tape 50 after passing through the two electromagnets 10, 20 can be demagnetized with the specified level or lower over the entire region. |
