| 摘要 |
PURPOSE:To obtain a dot with uniform type concn. even if an armature gap is not adjusted exactly in an impact type dot printing head, by forming a magnetic circuit driving the armature into a magnetism leakage type. CONSTITUTION:A hammer 2 having a dot printing member 1 mounted to a leading end thereof is forked into two branches in the vicinity of a center part thereof and other ends thereof are again joined to fix the armature 3 comprising a ferromagnetic material and integrally molded with a support member 4 having a hinge part 5. Further, a coil 7 is fixed to the support member 4 by a mold 8. When current is passed through the coil 7, because the armature 3 is attracted and moved into the coil 7, the hinge part 5 is bent and, thereby, the hammer 2 is revolved to protrude the dot printing member 1. In this case, because attractive force is not affected by an armature gap because of magnetism leakage type, it is unnecessary to exactly adjusting said gap. |
