| 摘要 |
PURPOSE:To accurately correct tracking and to miniaturize the titled device by supporting a magnetic head on one end of a supporting body constituted of shape memory alloy, a magnetic distortion material and a temperature sensitive magnetic material. CONSTITUTION:The supporting body 2 supports the magnetic head 1 by holding a base 6 between the shape memory alloy 3 and the magnetic distortion material 5 on one end and the other end is fixed on the inside of a rotary drum by fixing materials 7, 7. Magnetic field generators 8, 8 are arranged on the upper and lower parts of the supporting body 2 to impress AC and DC magnetic fields to the materials 4, 5. When the AC magnetic field is impressed, the shape memory alloy 3 is changed at its shape by joule heat generated in the material 4, but the material 5 is not changed and camber is generated in the supporting body 2 whose both the ends are fixed. When the level of the DC magnetic field is changed, the shape of the material 5 is changed, but alloy 3 is not changed and camber in the reverse direction can be generated in the supporting body 2. Consequently, accurate tracking correction can be attained and the shape can be miniaturized.
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