Patent ID: 8264123

Claim:
A piezoelectric vibration device system comprising: a piezoelectric vibration device that includes a piezoelectric element and that performs predefined movements using vibration of the piezoelectric element; and a control unit that controls a behavior of the piezoelectric vibration device by controlling a vibration frequency of the piezoelectric element, wherein the control unit includes: a first signal generating unit that generates a fundamental frequency signal having a fundamental frequency adjacent to a mechanical resonance frequency of the piezoelectric element; a second signal generating unit that generates a variable frequency signal having a frequency that periodically rises or falls according to a timing waveform having three discrete voltage steps along a time axis, each of the three discrete voltage steps having different voltage values; and a frequency modulator that generates a frequency modulated signal having a frequency that changes among one of three frequencies existing around the fundamental frequency periodically and in sequence, the frequency modulator generating the frequency modulated signal by frequency-modulating the fundamental frequency signal with the variable frequency signal, the frequency modulator outputting the frequency modulated signal as a control signal for controlling the piezoelectric vibration device.