PROBLEM TO BE SOLVED: To provide an ultrasonic vibration device that has heat resistance and prevents a short circuit between electrodes by preventing surface discharge between the electrodes in a construct made without lead.SOLUTION: An ultrasonic vibration device 2 comprises: a plurality of stacked piezoelectric single crystal plates 61 a plurality of electrodes 62, 63 having an area smaller than a front area and rear area of a piezoelectric single crystal plate 61 and placed between the plurality of piezoelectric single crystal plates 61 electric conduction parts 65, 66 for electrically connecting a positive electrode with other positive electrodes, and a negative electrode with other negative electrodes of the plurality of electrode plates 62, 63 on front and rear surfaces of the piezoelectric single crystal plate 61, flat region 61a where the electrode plates 62, 63 are not provided from an outer peripheral edge toward a center O by a prescribed length of L.COPYRIGHT: (C)2014,JPO&INPIT【課題】 耐熱性を備え、且つ非鉛の構成において、電極間の沿面放電を防ぐようにして電極間の短絡を防止した超音波振動デバイスの提供。【解決手段】 超音波振動デバイス2は、積層された複数の圧電単結晶板61と、圧電単結晶板61の表裏面積よりも小さな面積を有して複数の圧電単結晶板61間に介装された複数の電極板62,63と、複数の電極板62,63の正電極同士または負電極同士を電気的に接続する通電部65,66と、圧電単結晶板61の表裏面において、外周縁辺から中心Oに向かって所定の長さLだけ電極板62,63が設けられていない平面領域61aと、を備える。【選択図】図4
