| 摘要 |
PURPOSE:To improve printing quality or speed and simplify manufacturing process by fixing printing wire to a printing wire drive means so that a distance between the head of printing wire and the circumferential surface of a platen may be uniform when the printing wire drive means is not energized by electric power. CONSTITUTION:A coil 16, i.e. a printing wire drive means 15 is selectively energized by electric power, resulting in a reduction in the magnetic attractive power of a permanent magnet 18 by the flux of the coil 16 and the recoiling force accumulated in a leaf spring 20 exceeding the magnetic attractive force of the permanent magnet 18. Consequently, printing wire 23 is protruded toward a platen 3 and its printing had strikes on a paper 4 on the platen 3 to print the paper 4. In this printing operation, no difference in the print striking force occurs between printing wires because each distance between the head surface of the printing wire 23 and the circumferential surface of the platen 3 is uniform, thus improving printing quality. In addition, no difference in the operating time of a single printing cycle occurs between the printing wire 23, contributing to the improvement of printing speed. |
