| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a piezoelectric actuator capable of adjusting output easily within a sufficient range. <P>SOLUTION: An oscillator 266 is allowed to have a phase difference between the first and second drive signals S1 and S2+/S2- supplied to first and second drive electrodes 851 and 852, respectively. The phase difference allows amplitude to vary in bending vibration, thus achieving a desired elliptic locus E. Width is changed in the first drive electrode 851 along with the setting of the phase difference of such a drive signal, thus adjusting the elliptic locus E flexibly via the adjustment of the bending vibration, achieving the ideal elliptic locus E fulfilling desired drive characteristics, and hence allowing the piezoelectric actuator to adjust the output easily within a sufficient range regardless of the sizes of respective drive electrodes 851, 852. As a result, the output is increased by drive efficiency that is nearly two times larger than that when there is no phase difference in the drive signal, and drive can also be made in a reverse direction. <P>COPYRIGHT: (C)2007,JPO&INPIT |
