Abstract: An elastic sealing device includes a watertight holding section that is provided between adjacent frame bodies and holds watertightness and a packing section that is projectingly provided with respect to the watertight holding section and that is arranged in a gap between the adjacent frame bodies and forms a continuous outer surface.

Abstract: Electrode layers 22A-22C, 24A-24C are formed on both main surfaces of each of piezoelectric layers 20A, 20B. Voltages of different polarities are respectively applied to the electrode layers next to each other on the same main surface and to the electrode layers opposing to each other via the piezoelectric layer. Projection forms 30, 32 are formed in respective edges of the second electrode layers 22B, 24B, each of which extends into the opposite area. Through-holes are formed in the piezoelectric layer 20A, 20B, in positions off a division line 38. The electrode layers 22A-22C are connected together by the through-holes 26A, 26B and the projection form 30, to have an equal potential. Those are lead from the diaphragm to the outside, thus reducing the overall thickness.

Abstract: Electrode layers 22A-22C, 24A-24C are formed on both main surfaces of each of piezoelectric layers 20A, 20B. Voltages of different polarities are respectively applied to the electrode layers next to each other on the same main surface and to the electrode layers opposing to each other via the piezoelectric layer. Projection forms 30, 32 are formed in respective edges of the second electrode layers 22B, 24B facing to each other, each of which extends into the opposite area. Through-holes are formed in the piezoelectric layer 20A, 20B, in positions off a division line 38. The electrode layers 22A-22C are connected together by the through-holes 26A, 26B and the projection form 30, to have an equal potential. Those are lead from the diaphragm to the outside, thus reducing the overall thickness. This can reduce the thickness of a piezoelectric sounding body thus obtained and achieves lead reliability improvement, manufacturing process simplification and material diminishing.

Abstract: An enclosure of a cellular phone is formed with a plurality of sound releasing holes. The inside of a portion where the sound releasing holes are provided defines an air chamber formed with a receiving portion for mounting a piezoelectric sounding element. The piezoelectric sounding element is of bimorph structure formed by adhering piezoelectric elements on both surfaces of a diaphragm, and serves as a speaker by hermetically fixing a peripheral edge of the diaphragm to the receiving portion. Acoustic characteristics of such a piezoelectric sounding body relates to the total sum S of side surface areas of the sound releasing holes. Therefore, by setting the total sum to a value from 1.5 mm to 60 mm2, variations in resonant frequency and lowering of the sound pressure are prevented, and hence the required acoustic characteristics can be secured while realizing reduction of the thickness of the wall of the enclosure.