| 摘要 |
PURPOSE:To generate a sound pressure with a high level by locking other piezoelectric body of a closed structure to the circumferential part of the curved piezoelectric body having a couple of electrodes to both faces to form a cavity and providing a hole penetrated to the cavity and applying a voltage to the electrode. CONSTITUTION:A cavity 11 is formed by using a fixed body 20 so as to clip piezoelectric bodies 16, 17 of the curved shape and of the same size by a circumferential part 19. Electrodes 12-15 are fitted to both faces of the piezoelectric bodies 16, 17. One or over of sounding holes 18 are provided to the piezoelectric body 16. In applying a voltage to the electrodes 12-15, they are connected to be polarized in the same direction and an AC voltage is applied. Then the piezoelectric bodies 16, 17 are expanded and contracted and the air in the cavity 11 generates compressional waves through the sounding holes 18 thereby forming the sound. Thus. sounding body generating the sound pressure of a high level is manufactured easily.
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