| 摘要 |
PURPOSE:To obtain a sharp directivity and an excellent pulse characteristics, by providing a diaphragm at the center of a sticked type piezoelectric element, elastically fixing the surrounding of a diaphragm to a case with a buffer member and providing a thin plate having an opening in the front and a horn. CONSTITUTION:A diaphragm 13 is fitted to a coupling shaft 12 arranged at the center of a sticked type piezoelectric element 11. The surrounding of the diaphragm 13 is elastically fixed to the inside of a cylindrical case 17 via a buffer member 20 such as an elastic rubber formed in a circular ring. A sound absorbing member 21 is sticked at the bottom of the case 17. A circular opening 22 taking a straight line through the shaft 12 as a center, and a thin plate 23 having another opening 22' provided concentrically with the opening 22 are provided in front of the diaphragm 13, and the case 17 and the thin plate 23 are inserted to the bottle neck of a parabolic horn 24. Leads 19, 19' electrically connect the element 11 and terminals 16, 16'. Through the constitution of an ultrasonic wave transmitter/receiver like this, a sharp directivity and an excellent pulse characteristic can be obtained and accurate measuring information can be obtained in a short time interval. |
