| 摘要 |
PURPOSE:To improve the wear-resistant properties of a yoke in an engagement part with an armature by increasing the hardness of a yoke component part through a carburizing process of low-carbon steel used or a tempering process of high-carbon steel used. CONSTITUTION:In a printing head having a suction part 2 with a printing wire 1 formed at the tip, a core 5a adhering to the suction part 2, a permanent magnet 6 and a yoke 5b having a swinging fulcrum for the suction part provided on the surface contacting a permanent magnet 6, the entire surfaces of a yoke part 2, yoke 5b, core 5a and other materials, e.g. in the depth of 0.3-0.5mm., or tempered with high carbon steel for hardness increase. Thus it is possible to improve the wear-resistant properties of the engagement part with a suction part significantly without deterioration of the performance of a printing head. |
