| 摘要 |
PURPOSE:To enable a printing wire to be activated in a non-contact state and thereby prevent generation of an impact sound or abrasion by arranging an electromagnetic coil on the lateral surface of a permanent magnet through a gap so that the permanent magnet moves the printing wire in a specified direction by energization. CONSTITUTION:First an electromagnetic coil 13 is energized and then a permanent magnet 12 is moved to a position below in the figure resisting the energization of a leaf spring 14 by a mutual action between a force generated at right angles with the direction of an electric current in accordance with Fleming's rule. Next if a power supply to the electromagnetic coil 13 is shut off according to a printing signal, the magnetic field of the electromagnetic coil 13 disappears and a printing wire 7 is flipped up by the recoiling force of the comulatively energized leaf spring 14. Then dots are printed on a printing sheet through an ink ribbon. Thus a wire dot print head has no armature which collides with a stopper or becomes attracted to a core as seen in a print head based on a conventional technology. In addition, it is possible to prevent generation of an impact sound or abrasion as the printing wire 7 is activated in a non-contact state. |
