Ultrasonic motor and electronic apparatus equipped with ultrasonic motor

摘要

An ultrasonic motor comprises a piezoelectric vibrating member having a detecting polarized portion for detecting a drive signal having a drive frequency of the detecting polarized portion and a driving polarized portion for receiving the drive signal to oscillate the piezoelectric vibrating member in self-excited oscillation to produce a drive force. The detecting polarized portion is disposed at a portion of the piezoelectric vibrating member for undergoing maximum deformation in at least one vibration mode of oscillation of the piezoelectric vibrating member. An amplifying circuit amplifies the drive signal detected by the detecting polarized portion and inputs the amplified signal to the driving polarized portion to oscillate the piezoelectric vibrating member.