| 摘要 |
PURPOSE:To effectively oscillate ultrasonic waves toward the tip end of advancing crack and to receive an oscillation of reflection wave with a high sensitivity, by automatically adjusting the angle of arrangement between the oscillator and oscillation receiver. CONSTITUTION:A pair of leaf springs 1, 2 having a prescribed angle mutually is fixedly attached to a main body H of an ultrasonic probe apparatus A. A pair of piezoelectric elements 3, 3', 4, 4' provided on each spring 1, 2 are such elements that the mechanical strain is produced to a prescribed direction when a pulse row signal having a positive polarity is applied from an oscillator 6 through an electric power amplifier 5 and the mechanical strain is produced to a contrary direction when the pulse row signal having a negative polarity is applied. In case when the positive or negative pulse row signal is applied, mutual arrangement angle of the springs 1, 2 can be expanded or narrowed. An ultrasonic oscillator 9 connected to an oscillator 8 through an electric power amplifier 7 is provided on the tip end part of the spring 1 and an oscillation receiver 10 of the ultrasonic wave reflecting in a test piece S is provided to the tip end part of the spring 2. |
