| 摘要 |
PURPOSE:To remove a harmful ultrasonic wave signal due to acoustic coupling status monitoring and to attain proper testing by forming transmission pulses for the acoustic coupling status monitoring independently of testing transmission pulses. CONSTITUTION:Ultrasonic wave vibrators 2a, 2b excited by transmission circuits 1a, 1b generate ultrasonic beams and make the beams incident on a material 4. The transmission circuits 1a, 1b have timing exciting the ultrasonic vibrators 2a, 2b simultaneously and timing exciting only the vibrator 2b independently. The vibrators 2a, 2b receive ultrasonic wave signals obtained by reflecting the ultrasonic beams on the surface and the inside of the material 4 and input the received signals to respective receiving circuits 7a, 7b, the outputs of the receiving circuits 7a, 7b are added by an adder 10 and the added result is inputted to a signal processing circuit 8a to discriminate a defect. On the other hand, the output of the circuit 7b is inputted to a signal processing circuit 8b independently to monitor acoustic coupling status or the like. Consequently, a harmful ultrasonic wave signal due to the monitoring of the acoustic coupling status is removed and proper testing using ultrasonic waves can be attained. |
