| 摘要 |
PURPOSE:To improve plunger operation and to contrive to make high speed by a method wherein a communication hole, where space formed between one end of the plunger and a bottom section of a casing communicates to outside, is provided to the casing, at the time when the plunger is seceded from the bottom section of the casing. CONSTITUTION:When a coil 15 is excited, a plunger 12 initiates to shift to the arrow W direction by electromagnetic force thereof. When the plunger 12 returns toward the section of a casing 13, a tongue section 21b of a check valve 21 closes an air hole 18, but since air in a space S gets out through a communication hole 18g at the latter half return motion, the communication hole 18g is closed gradually, then the communication hole 18g has been closed completely at the range of the return motion gets to about 3/4, thus the return force is weakened by flow resistance of air and the plunger 12 stops to established position comparative gently. Printing operation is performed by such a continuous motion. |
