UNDERWATER ULTRASONIC WAVE TRANSDUCER

PROBLEM TO BE SOLVED: To obtain a small-sized lightweight underwater ultrasonic wave transducer that has a broadband sound radiation characteristic with high efficiency and is capable of high power wave transmission. SOLUTION: In the underwater ultrasonic wave transducer that has a bolt tightened Langevin vibrator formed by engaging a bolt 14 exerting a compression stress to a piezoelectric ceramic laminator 11 with a front mass 13 and a rear mass 12, a recessed part is formed to a front face of the front mass 13, and a bending diaphragm 13 is fixed to the front side of the front mass 13 by using a heavy duty adhesive and bolts 16 or electron beam welding. A bending diaphragm 15 has a rigid body parallel displacement by elongation/ contraction of the piezoelectric ceramic laminator 11 and a bending displacement of the bending diaphragm 15 itself supported at the surrounding. The size of the recessed part is optimally designed so as to superimpose the two vibration modes for broadband operations. The mechanism components are strongly joined by the bolt or the like and the small sized lightweight transducer with high mechanical strength that sufficiently stands a high power transmission wave can be obtained.