| 摘要 |
PURPOSE:To enable magnetic efficiency to be improved by extending a tongue- shaped part of a yoke plate between both sides of each printing lever and constituting a magnetic channel running through printing lever, yoke plate, yoke frame and iron core. CONSTITUTION:If a drive signal is applied to a coil 8 and an iron core 7a excited, a protrusion of a printing lever 14 is attracted, and an inner edge 14a advances pushing a printing element forward. A magnetic flux frm the iron core 7a passes through an outer edge 14b from the protrusion of the print ing lever 14 and returns to the iron core 7a after passage through a yoke frame. At the same time, the magnetic flux runs through a tongue-shaped part 15c of a yoke plate 15 on both sides of said protrusion and an external circumferen tial section 15a from the iron core 7a and returns to the iron core 7a via a yoke frame 7. Thus the printing lever 14 can be driven by a sufficiently large magnetic attraction force, even if said lever lacks enough cross section because of disk-like form. Consequently, magnetic efficiency is improved.
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