Patent ID: 8410671

Claim:
A vibratory actuator, comprising: a piezoelectric element configured by alternately stacking a plurality of piezoelectric layers and a plurality of electrode layers, wherein each of the piezoelectric layers includes a pair of principal surfaces and side surfaces formed along the periphery of the pair of principal surfaces, and is polarized along a direction in which the pair of principal surfaces face each other, the plurality of electrode layers include a positive electrode layer, which serves as an anode when a voltage is applied in a forward direction with respect to the polarization direction of a corresponding one of the piezoelectric layers, and a negative electrode layer, which serves as a cathode when a voltage is applied in a forward direction with respect to the polarization direction of a corresponding one of the piezoelectric layers, the positive electrode layer includes four positive split electrodes respectively provided in four regions obtained by halving a principal surface of the piezoelectric layer respectively in the longitudinal and the lateral directions thereof, and a positive diagonal-connection electrode connecting together a first pair of positive split electrodes disposed along one diagonal direction among the four positive split electrodes; and a second pair of positive split electrodes, which are not connected together by the positive diagonal-connection electrode among the four positive split electrodes, are connected together outside the positive electrode layer, and the negative electrode layer includes four negative split electrodes opposed to the four positive split electrodes of the positive electrode layer across the piezoelectric layer, and a negative diagonal-connection electrode connecting together a first pair of negative split electrodes disposed along one diagonal direction among the four negative split electrodes; and a second pair of negative split electrodes, which are not connected together by the negative diagonal-connection electrode among the four negative split electrodes, are connected together outside the negative electrode layer.