| 摘要 |
PURPOSE:To print at high speed and with high accuracy by a printing head and enable construction of a small printing head, by providing a magnetic circuit for driving a spring charge type printing wire constituted of an integral form outer peripheral yoke consisting of the same magnetic pole, a magnet and a yoke. CONSTITUTION:The integral form outer peripheral yoke 8 consisting of the same magnetic pole is provided, the magnet 9 is fitted to the inner peripheral surface of the yoke 8, and the yoke 10 is fitted to the other surface of the magnet 9. By this construction, the surface area of the yoke 10 through which a magnetic flux leaks from the yoke 10 to the yoke 8 can be reduced, and the leakage flux from the yoke 10 to the yoke 8 with a pole different from that of the yoke 10 can be reduced. Accordingly, an attractive force can be increased, and it can be contrived to enhance printing speed. The form of the magnetic circuit can be reduced by fitting the magnet 9 to the inner peripheral surface of the yoke 8, thereby making it possible to reduce the size of the yoke 8. |
