| 摘要 |
PURPOSE:To obtain a highly reliable printing hammer capable of high-speed action, by providing a leaf spring comprising a print needle and a flying member, the first piezoelectric element for exerting a force on the flying member through a surface of a force-transmitting member, and the second piezoelectric element for damping a returning motion of the flying member through a shock- absorbing member. CONSTITUTION:The leaf spring 13 comprising the print needle 11 and the flying member 12 at a free end thereof is fixed to a mount member 14. The first and second piezoelectric elements 15, 16 are connected to the mount member 14 in parallel with each other, on the back side of the flying member 12. The elements 15, 16 are so disposed that they are expanded and contracted toward and away from the flying member 12. The force-transmitting member 17 formed of a hard material such as a metal is provided on a front face of the first piezoelectric element 15, and the flying member 12 is pressed by the spring 13 against the member 17 so that the members 17, 12 make contact with each other. The shock-absorbing member 18 formed of a rubber or a plastic is provided on a front face of the second piezoelectric element 16. |
