| 摘要 |
PROBLEM TO BE SOLVED: To prevent erroneous determination of a reflecting source in a pipeline by judging the received signal of reversed phase which revealed next the re ceived signal of reversed phase revealed first as false signal. SOLUTION: A sound wave is transmitted from the sound generating means 11 of an acoustic wave pipeline examining device 10 arranged in one A of end parts of a pipeline P1, and the received data of the reflected acoustic wave is stored. The reflecting condition of a part other than A, for example, the end part C of a branched pipe P, is changed, the acoustic wave is transmitted from the sound generating means 11, and the received data of the reflected acoustic wave is stored. Both the data are mutually compared. In this comparison, the first received signal of the received signals of reversed phase is judged as the received signal from the end part where the reflecting condition is changed, or the end part C of the branched pipe P2, and the next received signal of reversed phase is judged as a false signal. Thus, since the distance obtained from the received timing of the received signal can be ignored when the false signal is found, the possibility of erroneous determination that a reflection source is present in the position of this distance can be eliminated. |
