Patent ID: 7298066
Filing Date: 2007-11-20
Classification: H01L,H02N

Abstract:
1. A drive apparatus for a piezoelectric actuator having a piezoelectric element being configured to vibrate by application of a drive signal with a specific frequency, said drive apparatus comprising: vibration state detection means for detecting a vibrating state of said piezoelectric element and for outputting a detection signal; harmonics detection means for detecting resonating of said piezoelectric element due to harmonics of said drive signal and for outputting a harmonics detection signal; and frequency control means for supplying said drive signal to said piezoelectric element while controlling said frequency of said drive signal, for controlling said frequency of said drive signal based on said detection signal when said harmonics detection is not outputted from said harmonics detection means, and for controlling said frequency of said drive signal based apart from said detection signal when said harmonics detection is outputted apart from said harmonics detection means.