| 摘要 |
PURPOSE:To detect a flaw part with high accuracy by removing a dummy echo and to measure the size thereof, by differentiating the angles of refraction of the probes of a transmitting multiple ultrasonic probe and those of the probes of a receiving multiple ultrasonic probe to perform transmission and reception. CONSTITUTION:Scanners 1, 2 are provided to the outer periphery of the hub W2 of an object W to be detected so as to be freely runnable is synchronous relationship and a transmitting multiple ultrasonic probe 3 provided with a transmitting probe 3a transmitting an ultrasonic wave at the angle of inclination being the angle of refraction of the probe of about 40-50 deg. and transmitting probes 3b, 3c transmitting ultrasonic waves at the angle of inclination being the angle of refraction of the probes of about 65-75 deg. is provided to the scanner 1. A receiving multiple ultrasonic probe 4 provided with receiving probes 4a-4c receiving ultrasonic waves at the angle of inclination being the angle of refraction of the probes in the same way is provided to the scanner 2. The transmitting beams of the probes 3a, 3b, 3c are changed over so that the signals obtained by the probes 3, 4 are processed by a signal processor 12 through a multi-channel pulser receiver 9 and an A/D converter 11 not only to detect the flaw part of the object W to be detected but also to measure the size thereof. |
