| 摘要 |
PURPOSE:To decrease the irregularity of the sound pressure response and to suppress the secondary harmonic distortion by setting a ratio DP/DO of a diameter DO of a diaphragm and that DP of an electrode opposite to a piezoelectric ceramic convertor to a range of 0.75-0.85. CONSTITUTION:A diaphragm 1, a supporting tool 2 and a coupling part 3 are worked by press from a one sheet of metallic plate, and a circular piezoelectric ceramic convertor 4 is adhered to the center of the main surface of the diaphragm 1. A piezoelectric speaker is constituted in such a way that one sheet of damping plate 7 is so adhered to cover peripheries of other main surfaces of the diaphragm 1, the supporting tool 2 and the coupling part 3, and the supporting tool 2 is fitted to a holding device 6. Assuming that a diameter of an electrode opposite to the convertor 4 and a diameter of the diaphragm are DP and DO, respectively, a ratio DP/DO of them is set to 0.75-0.85. Thus the irregularity of the sound pressure response can be made smaller, and the secondary harmonic distortion can be suppressed. |
