| 摘要 |
PURPOSE:To provide an ultrasonic flaw detector that issues an alarm without being affected by noise nor damaging operativity. CONSTITUTION:A counter 5 that, when defective echo (ii) level exceeds detection level (ii'), counts synchronous pulse (iv) synchronized with transmission pulse, and a coincidence detecting circuit 9 that detects coincidence between the count value and set value (2'' of 9), in accordance with noise level, are provided, so that an alarm signal (x) is outputted in accordance with detection of coincidence. With this, the detection frequency of defective echo for issuing alarm is automatically changed in correspondence with changes in pulse repetition frequency. Therefore, the setting of pulse repetition frequency can be freely changed with no adjustment of alarm. |
