Drive unit

摘要

A drive unit includes an ultrasonic actuator having an actuator body formed using a piezoelectric element, and a driving element provided on the actuator body and configured to output a driving force by moving according to the vibration of the actuator body, and a control section configured to induce the vibration in the actuator body by applying a first and a second AC voltages having a same frequency and different phases to the piezoelectric element. The control section adjusts the first AC voltage and the second AC voltage so that the first AC voltage and the second AC voltage have different voltage values from each other.

主权项

1. A drive unit, comprising:
a vibratory actuator having an actuator body and configured to output a driving force by inducing vibration in the actuator body, the actuator body including a piezoelectric element in a substantially rectangular shape and an electrode layer having first power-supply electrodes and second power-supply electrodes on a substantially rectangular face of the piezoelectric element, the first power-supply electrodes arranged in one of two diagonal directions of the substantially rectangular face, and the second power-supply electrodes arranged in the other of the two diagonal directions of the substantially rectangular face, and a control section configured to induce the vibration in the actuator body by applying a first and a second AC voltages having a same frequency and different phases to the electrode layer, the first AC voltage applied to the first power-supply electrodes, and the second AC voltage applied to the second power-supply electrodes,wherein
the control section adjusts the first AC voltage and the second AC voltage so that the first AC voltage and the second AC voltage have different effective values from each other, and an effective value of a first AC current flowing in response to the first AC voltage is different from an effective value of a second AC current flowing in response to the second AC voltage.