| 摘要 |
PURPOSE:To reduce the wt. of a head and to increase a recording speed, by constituting at least a part of the constitutional member of a magnetic circuit for driving a wire by magnetic force of a composite member formed by mixing a magnetic powder and a resin. CONSTITUTION:In a head, a magnetic circuit for driving a wire 2 is constituted as a closed magnetic path consisting of a coil core 6a, a yoke 6, a spacer 12, an auxiliary yoke 13, and armature lever 15 and a movable core 16. The movable core 16 is formed from a composite material formed by mixing a magnetic powder and a resin. As the magnetic material of the magnetic powder, one having saturated magnetic flux density higher than that of pure ion is used and, when the mixing ratio of the magnetic powder and the resin is properly set, the quantity of the magnetic flux PHI flowing to the movable core 16 can be kept equal and, by lowering the specific gravity of the composite material through the resin which is low in specific gravity, the equivalent mass of the movable core 16 can be reduced. Therefore, the operational speed of the movable core 16 is increased to make it possible to increase that of the wire 2 operating in conjunction therewith and a recording speed is increased. |
