| 摘要 |
PURPOSE:To prevent the generation of the stress concentration in a bonded part at the time of the driving of a printing wire and to enhance not only the durability of the printing wire but also reliability, by providing a triangular protruding part to the leading end part engaging with the printing wire of an armature. CONSTITUTION:Since a triangular protruding part 2a is provided to an armature 2 at the junction with a printing 1 of said armature, the printing wire 1 is smoothly bonded to the protruding part 2a of the armature 2. When the armature 2 is driven by a leaf spring 6 during a printing process, the printing wire receives large bending stress at the leading end A of the triangular protruding part 2a of the armature 2 but, since the printing wire 1 and the leading end of the triangular protruding part 2a are smoothly connected, stress concentration is not generated at the point A of the printing wire 1. Therefore, the durability of the printing wire 1 at the point A is drastically enhanced and the reliability of a wire dot head can be markedly enhanced. |
