In order to suppress the influence of the ultrasonic waves by electromagnetic noise and measures the elasticity information of the subject based on the propagation speed of the shear wave using a probe that visualized ultrasound generic ultrasonic tomographic image, Unit 14 vibration of the invention, the guide rail 82 and the mounting member 72 that is removably attached to the ultrasound probe 12, is provided to extend from the rear end of the mounting member, and along the guide rail cuff member 84 provided slidably Te, a stopper 80 for regulating direction of sliding of the cuff member (downward), and is prestressed by being slid in the direction of the cuff member is separated from the stopper It is configured to have the spring 86 tension a pair of which are provided so that, with the locking mechanism for locking the excitation member at a position where the vibrating member is prestressed, and an unlocking mechanism for unlocking the locking mechanism that.超音波断層像を描出可能な汎用的な超音波探触子を用いて剪断波の伝搬速度に基づく被検体の弾性情報を計測し、かつ電磁波ノイズによる超音波への影響を抑制するために、本発明の加振ユニット14は、超音波探触子12に着脱自在に装着される装着部材72と、装着部材の後端から延在して設けられたガイドレール82と、このガイドレールに沿って摺動可能に設けられた加振部材84と、加振部材の摺動の一方向(下方向)を規制するストッパ80と、加振部材がストッパから離れる方向に摺動されて蓄勢されるように設けられた一対の引張りバネ86と、加振部材が蓄勢された位置で加振部材をロックするロック機構と、ロック機構のロックを解除するロック解除機構とを有して構成される。
