PROBLEM TO BE SOLVED: To perform treatment over a long time by allowing continuous drive over the long time of an ultrasonic transducer in which a width between a resonance frequency and an antiresonance frequency is narrow.SOLUTION: An ultrasonic treatment device 1 includes: a tip part 9 for treating a treatment target region by ultrasonic vibration driving piezoelectric elements 10 for vibrating the tip part 9 by applying drive voltage varying at a drive frequency a detecting piezoelectric element 12 disposed adjacently to the driving piezoelectric elements 10 through an insulating member 7, for converting the vibration generated by the driving piezoelectric elements 10 into a voltage signal a frequency setting part 14 for setting the drive frequency of the drive voltage supplied to the driving piezoelectric elements 10 a phase difference calculation part 17 for calculating a phase difference between the drive voltage and the voltage signal detected by the detecting piezoelectric element 12 and a frequency control part 18 for controlling the frequency setting part 14 on the basis of the phase difference calculated by the phase difference calculation part 17.COPYRIGHT: (C)2014,JPO&INPIT【課題】共振周波数と反共振周波数の幅の狭い超音波振動子の長時間にわたる連続駆動を可能として、長時間にわたる処置を行う。【解決手段】超音波振動により処置対象部位を処置する先端部9と、駆動周波数で変動する駆動電圧を加えることにより先端部9を振動させる駆動用圧電素子10と、該駆動用圧電素子10に絶縁部材7を介して隣接配置され、駆動用圧電素子10により発生した振動を電圧信号に変換する検出用圧電素子12と、駆動用圧電素子10に供給する駆動電圧の駆動周波数を設定する周波数設定部14と、検出用圧電素子12により検出された電圧信号と駆動電圧との位相差を算出する位相差算出部17と、該位相差算出部17により算出された位相差に基づいて周波数設定部14を制御する周波数制御部18とを備える超音波処置装置1を提供する。【選択図】図1
