| 摘要 |
PURPOSE:To attain low power consumption and also high erasure rate by erasing a magnetized magnetic recording medium with a multipole permanent magnetic erase head and then erasing the residual magnetization with an electromagnet type erasure head. CONSTITUTION:The magnetic recording medium C is erased to the residual magnetic field I0 as shown in Fig. by the multipole permanent magnetic erase head (a) at first. Then the medium is erased to a rate over a desired erasure rate by the electromagnet type erase head (b). Since only the residual magnetization after the erasure of the multipole permanent magnet erase head (a) is erased by the electromagnet type erase head (b) in this way, the power consumption is lower than a conventional consumption. Since the erasure is attained in two stages, a higher erasure rate is obtained in comparison with the use of the multipole permanent magnet head (a) only. |
