VIBRATION-TYPE ACTUATOR, DRIVING METHOD FOR VIBRATION-TYPE ACTUATOR, AND ELECTRONIC APPARATUS EQUIPPED WITH VIBRATION-TYPE ACTUATOR

摘要

A vibration-type actuator that is capable of reducing an unnecessary vibration during driving. A vibration body is configured by connecting an electro-mechanical energy conversion element and an elastic body. A driven body is in pressure contact with the vibration body. A controller moves the vibration body and the driven body relatively by a vibration that is excited in the vibration body by applying driving voltage to the electro-mechanical energy conversion element so that a difference between a resonance frequency in a natural vibration mode of the vibration body that is higher than an upper limit frequency of a predetermined driving frequency range and that is nearest to the upper limit frequency and a frequency of the driving voltage is larger than a difference between a resonance frequency in a natural vibration mode used for moving the vibration body and the driven body relatively and the frequency of the driving voltage.

主权项

1. A vibration-type actuator comprising:
a vibration body that is configured by connecting an electro-mechanical energy conversion element and an elastic body; a driven body that is in pressure contact with said vibration body; and a controller configured to move said vibration body and said driven body relatively by a vibration that is excited in said vibration body by applying driving voltage to the electro-mechanical energy conversion element so that a difference between a resonance frequency in a natural vibration mode of said vibration body that is higher than an upper limit frequency of a predetermined driving frequency range and that is nearest to the upper limit frequency and a frequency of the driving voltage is larger than a difference between a resonance frequency in a natural vibration mode used for moving said vibration body and the driven body relatively and the frequency of the driving voltage.