| 摘要 |
PURPOSE:To ensure the erase lof specific track without giving effect to other tracks, by providing the magnetic substance in which magnetism-non-magnetism change is made by temperature, at the magnetic gap of each head element, and changing the temperature simultaneously or selectively. CONSTITUTION:The spacers 4, 4' made of magnetic material are placed at the gap of tip of the magnetic cores 1, 1' of the first and second channel, and the heaters 5, 5' are placed near the gap. The Curie temperature of the said spacers 4, 4' is set to a little higher value than the usage temperature. In normal state, the spacers 4, 4' are ferro-magnetic substance and even if magnetic flux passes through the cores 1, 1', it is shut at the spacers 4, 4' and not leaked out. But when the heater 5' is heated, the temperature is in excess of the Curie point at the spacer 4' into non-magnetism, and when current flows into the winding 3', leakage is caused at the spacer 4' to erase the second track. In this case, a part of magnetid flux is leaked to the first channel, but the magnetic flux is shunted due to ferro-magnetism of the spacer 4 to inhibit leakage and the signal on the first track is not erased. |
