| 摘要 |
PURPOSE:To compensate the sensitivity fluctuations of flaw detection signals automatically by receiving the reflected echoes within a resin wedge, and controlling an AGC circuit by the signal which is the result of the prescribed operation. CONSTITUTION:The pulses from a transmission and reception part 11 are reflected by the bottom surface of a resin wedge 2 and the surface of a specimen 4 via a vibrator 1 for transmission and reception, and are received as an echo 8 in a vibrator 3 for monitoring. They are also applied via a contact medium 6 into the specimen 4 and the beam reflected from a detect 5 is received in the vibrator 1. The output of the vibrator 3 is fed via a reception part 12 to an arithmetic circuit 13. The arithmetic expressions expressing the fluctuating relations of the signal of the echo 8 and flaw detection sensitivity are beforehand set in the circuit 13 by using test pieces and the like, and the results of th prescribed operations in accordance with these are applied to an AGC circuit 14 to control its operation. As a result, the AGC circuit 14 is automatically compensated of sensitivity and the defect signal is applied to a monitor 15. |
