| 摘要 |
PROBLEM TO BE SOLVED: To radiate the sound of a low frequency, and to miniaturize and lighten an acoustic transducer.SOLUTION: The acoustic transducer 1a for radiating a sound wave into a medium in the air or in the water or the like includes: a shaft (shaft member) 2 which extends at a center part of the acoustic transducer 1a; first and second cylindrical acoustic radiation plates 4 and 5 alternately arrayed in an axial direction with the shaft 2 as a center axis; ring-like connection members 6 which connect the end parts of the adjacent first and second acoustic radiation plates 4 and 5; and bending vibration plates 7 which connect the shaft 2 and the connection member 6 and have a piezoelectric vibrator (vibrator) 8. The cross sectional shape of the first acoustic radiation plate 4 on a plane including the axis is curved outwardly, and the cross sectional shape of the second acoustic radiation plate 5 on a plane including the axis is curved inwardly. An end plate 3 is provided on both end parts of the shaft 2. |
