| 摘要 |
<p>A driving device (14) of an acoustic vibration plate (11) is arranged between a speaker frame (10) and the acoustic vibration plate (11). The driving device (14) is comprised of a pair of piezoelectric vibration plates (1, 2) arranged facing each other across a certain distance. The outer peripheries of the piezoelectric vibration plates (1, 2) are connected to each other by an annular spacer (7). When a drive signal is applied to the piezoelectric vibration plates (1, 2), the piezoelectric vibration plates (1, 2) repeatedly undergo flexing motion wherein their centers flex alternately in opposite directions. At this time, the flexing directions of the piezoelectric vibration plates (1, 2) are always reverse to each other. <IMAGE></p> |
