Patent ID: 9276502
Filing Date: 2016-03-01
CPC Classification: G02B,H02N

Claim Text:
1. A vibration-type motor controller which controls a driving speed of a vibration-type motor relatively moving a vibrating body in which a vibration is excited by an electromechanical energy conversion element to which a first frequency signal and a second frequency signal having a phase difference are applied, and a contacting body which contacts the vibrating body, the vibration-type motor controller comprising: a speed controller configured to switch a first speed control and a second speed control, the first speed control combining a frequency control and a phase difference control, the frequency control changing frequencies of the first and second frequency signals while fixing the phase difference between the first frequency signal and the second frequency signal, the phase difference control changing the phase difference while fixing the frequencies of the first and second frequency signals, and the second speed control performing the frequency control without performing the phase difference control to increase and decrease the driving speed of the vibration-type motor.