| 摘要 |
PURPOSE:To make a motor into compact in size and lighter in weight, besides simple in structure as well as to get rid of any noise against an electronic control unit by using this motor which is structured to move a needle with progressive waves generated in an elastic body by two types of high frequency voltage. CONSTITUTION:A motor M1 driving a control valve V1 is structured as having two piezoelectric elements 13, 14 and an elastic body 18, a needle 20 set up in rectilinear form. Here, when different high frequency voltage is impressed on each of these piezoelectric elements 13, 14, a progressive wave is produced in the elastic body 18. The needle 20 is moved by this progressive wave. The control valve V1 directly connected to the needle 20 rectilinearly reciprocating regulates a passage area of an idle air passage 33 at an interval between full- close and full-open. The motor M1 structured like this is compact in size and lighter in weight, besides simple in structure as well as it can eliminate occurrence of any noise against an electronic control unit. In addition, the control valve V1 is steplessly drivable with high responsiveness and controllability owing to a simple control means, saying that phases of the high frequency voltage are shifted according to a driving state. |
