| 摘要 |
PURPOSE:To obtain a release-type printing head having excellent printing characteristics and capable of high-speed printing, by providing a first fulcrum for deflecting a leaf spring by a magnetix flux of a permanent magnet and a second fulcrum for adjusting an impact force of the leaf spring. CONSTITUTION:When a coil 5 around a core 3 is excited and an armature 11 is released from attraction, a wire 13 collides against a platen 20. By an impact force Fimp generated at this moment, a moment Mimp around an impact center G in the armature 11 is generated, as shown in Fig. (b), and the armature 11 tends to rotate about the impact center G. At this moment, a leaf spring 10 is restrained from moving upward, by a pressing force fsb exerted by an auxiliary spring 15 (second fulcrum). A downward reaction of the leaf spring 10 generated subsequently is restrained, this time, by a protrusion 9a (first fulcrum). Namely, the leaf spring 10 is restrained from motion on both the upper and lower sides by the impact center G, the auxiliary spring 15 and the protrusion 9a, so that the leaf spring 10 is restrained from being vibrated by the impact force Fimp. |
