| 摘要 |
PURPOSE:To erase a recorded data without needing any erasure head by providing an erasure layer having a prescribed saturated magnetic flux density near a gap at the side of a slide face of a core. CONSTITUTION:An erasure layer 14 with a saturated magnetic flux density smaller than the saturated magnetic flux density of a core 11 and a permeability equal to that of the core 11 is provided near a gap at the slide face side of the core 11 with a recording and reproducing gap 12 formed thereto. In case of giving a recording current to the core 11, a leakage magnetic flux 19a is generated in response to the recording current, and a data 19b is recorded on a recording medium 18. In this case, a leakage magnetic flux 20a is generated also to an erasure layer 14 and since the flux exists precedingly with respect to the gap 12, the recorded information is erased. Furthermore, in case of reproduction, since the magnetic flux quantity is less in comparison with that at recording, the erasure layer 14 is not saturated and no effect is given onto the reproduction. |
