| 摘要 |
PURPOSE:To make assembly/disassembly easy and improve printing quality by providing a hammer mount which fixes a plurality of hammer bases on the external side of a base with a plurality of columnar cores planted on the internal side, and also installing a shunt forming the closed magnetic circuit of each coil with a permanent magnet attached to the external side of a shunt and a hammer mount in the outer circumference of a base. CONSTITUTION:A hammer mount 52a is provided on the external side, with a plurality of cores 54-1, 54-2... planted on the internal side, and at the same time, a ring-shaped base 52 equipped with a shunt 52b is installed in close proximity to the hammer mount 52a. In addition, a permanent magnet 48 is externally fitted to the external side of the shunt 52b and the hammer mount 52a in the outer circumference of the base 52. To improve printing quality, it is necessary to make a preload on the hammer by magnetic force as uniform as possible so as to prevent a variation from being generated in hammer speed. The preload can be easily adjusted by changing a magnetic circuit. |
