| 摘要 |
PURPOSE:To make it possible to effectively prevent the damage of a specimen or an ultrasonic head, by detecting the contact of the specimen with the ultrasonic head. CONSTITUTION:An ultrasonic head 11 having a piezoelectric transducer is attached to the almost central part of a conductive rod 12 extending to a direction crossing the projection direction of an ultrasonic wave at right angles in a freely detachable manner and the support rod 12 is held to a conductive fixing member 15 in both sides of the ultrasonic head 11 through air bearings 13, 14 while both end parts thereof are supported by a leaf spring attached to the fixing member 15 in an electrically insulated state so as to be made displaceable in the longitudinal direction. A current supply detecting circuit is connected between the fixing member 15 and the support rod 12 and, when the ultrasonic head 11 is contacted with a specimen at the parts of the air bearings 13, 14 and the support rod 12 is contacted with the fixing member 15, an alarm circuit is operated by the output of the current supply detecting circuit. |
