| 摘要 |
PURPOSE:To change magnetic flux passing through a magnetic path bypassing the magnetic flux of a magnet and compensate the variation of printing time due to the deterioration of a flat spring by the reduction of magnetic flux passing through an armature by a method wherein the magnetic path is formed, and the by-path magnetic path is moved. CONSTITUTION:This invention relates to a wire dot head capable of obtaining a stable printing characteristic for a long time. When the elasticity of a flat spring 4 is strong, relationship between magnetic flux phi2 passing through an armature 5 and printing time T is shown in a full line in the figure. When the elasticity of the flat spring weakens due to wear, the relationship between phi2 and T is shown in a one point chain line. When a magnetic material 8 for by-path is moved in the arrow head direction and magnetic flux phi1 is increased, the magnetic flux phi2 passing through the armature 5 decreases only by the increasing section, an operating point moves to (c) and the printing time T can be returned to original T1. Thus, the variation of the printing time due to the deterioration of the flat spring can be compensated. |
