| 摘要 |
PURPOSE:To vary the spring constant of a thin plate spring by installing piezoelectric elements onto the both sides of a thin plate spring and hooking the piezoelectric elements onto the projections on a side wall by the extension and contraction due to the piezoelectric effect and adjusting the length of the thin plate spring, using said projections as fixed edge. CONSTITUTION:A thin plate spring 1 has piezoelectric elements 2 at proper intervals at the both edges in the longitudinal direction, and fixed onto a side wall 4 by a fixed edge 3, and said side wall 4 has a projection 5 along the thin plate spring 1. Though the piezoelectric element 2 is not ordinarily hooked with the projection 5, the extension and contraction is generated when a voltage is applied, and the piezoelectric element 2 is hooked with the projection 5. The position of the piezoelectric element 2 hooked with the projection 5 forms the fixed edge of the thin plate spring 1. The spring constant of the leaf spring is represented by K=bk<3>E/4l<3> (k is the thickness of the spring plate, and b is the width of the spring plate, and l is the total length of the spring plate, and E is Young's modulus), and since the plate thickness (k) and the plate width (b) are not varied, the total length (l) of the thin plate spring from the fixed edge is varied when the position of the fixed edge is varied by utilizing the piezoelectric element 2, and also the spring constant K is varied. |
