| 摘要 |
PURPOSE:To realize excellent performance and high productivity and to improve the distortion of a coil, by moving two moving coils in a magnetic field by the oscillation of a needle point to obtain a reproduction output, and by making a coil holder of an aluminum. CONSTITUTION:A coil holder 3 is coupled to one end of a cantilever 2 which is fixed with a needle point 1 on its another end to support it so that it can move freely with a supporting point near to the center of the coil holder 3, and moving coils 4 and 5 are fixed on its outer peripheral so that their wound coil plain surfaces are located in a surface perpendicular to the main axis of the cantilever. Magnetic gaps 21 and 22 are formed between a front yoke 20 and poles 18 and 19 which are arranged so that they face each other with the poles, which are inserted in the center holes of the coils 4 and 5, and the coils 4 and 5 in-between. A permanent magnet 24 between the front yoke 20 and a rear yoke 23 generates a magnetic field. If the coils 4 and 5 are moved in the magnetic field, a reproduction output is obtained. Thus, the excellent performance and high productivity are realized. Since the coil holder is made of an aluminum, the distortion of the coil becomes small. |
