| 摘要 |
PURPOSE:To provide a printing hammer mechanism of a dot impact printer which enables energy efficiency to be increased and production cost to be out with its weight decreased by installing a spring buckle which snaps in response to the rocking of the other end of a lever arm operating according to the expansion of a piezoelectric element. CONSTITUTION:If a voltage is applied to a piezoelectric element 2, it rapidly contracts in the arrow A direction under a static polarization effect. The input end 3a of a lever arm 3 is pulled in the arrow A direction following the contraction of the piezoelectric element 2. Consequently, the lever arm 3 rotates around a hinge 4 and an output end 3c rapidly moves in the arrow B direction, magnifying the contracting action of the piezoelectric element 2. Along with the movement of the output end 3c of the lever arm 3, the center of a U-shaped outer frame 8 also moves in the arrow B direction. If the center of the U-shaped outer frame moves to some extent in the arrow B direction, a snap action generates under the effect of a spring buckle 7, allowing the printing wire 6 of a printing hammer 5 to jump out in the arrow C direction because of its sudden and significant displacement. Thus the printing wire performs a predetermined printing job. |
