| 摘要 |
PURPOSE:To reduce magnetic interference between magnetic circuits and obtain a printing head for a dot printer capable of enhancing the printing speed of characters, by a construction wherein two yokes provided on opposite sides of a permanent magnet are adhered in the condition of being directed perpendicularly to each other. CONSTITUTION:The magnetic poles of the two yokes 10, 11 are so shaped that adherend surfaces for the permanent magnet 9 are extended in directons perpendicular to each other. Further, at opposed parts of the magnetic poles constituting a magnetic gap 12, the yokes 10, 11 are so shaped 10'', 11'' as to be extended in the thickness direction of the permanent magnet 9. The shapes of the yokes are made to be different for the same magnetic pole (10, 10' and 11, 11'). The yokes are so combined that the yoke shapes for adjacent magnetic circuits are equivalent with the axis (a) of ovelapping of the circuits as an axis of symmetry and the magnetic poles are the same, and a multiplicity of magnetic circuits for driving printing pins are provided on the circumference of a circle. Accordingly, a magnetic circuit containing space is effectively utilized, the shape of a magnetic path of each magnetic circuit is so set as to prevent magnetic interference, magnetic leakage is reduced, and the magnetic field generated at the magnetic gap is increased. |
