| 摘要 |
PURPOSE:To give a function as a strain gage jointly in addition to a function as a piezoelectric actuator by extracting a signal by utilizing a phenomenon in which the electric resistance value of an electrode plate formed in folding structure is changed by bending stress. CONSTITUTION:Both electrode plates 4, 5 are shaped in folding structure. That is, a large number of pectinate notches 10 are formed zigzag to these electrode plates 4, 5, and an effective electric wire is lengthened and an electric resistance value is increased by the notches 10, thus using these two electrodes plates 4, 5 of the surface and the rear as a strain gage as they are. When one end section (a left end section in the figure) of a piezoelectric actuator is fixed and the other end section (a right end section in the figure) is given desired displacement, a movable end (the right end in the figure) follows signal voltage and is displaced because one of substrates 2, 3 is elongated and the other is shrunk by an inverse piezoelectric phenomenon when signal voltage is applied between terminals T, U. Since the electric resistance values of the electrode plates 4, 5 change owing to the bending stress of the substrates 2, 3 at that time, the change is measured electrically and the quantity of strain can be measured. |
