To provide a hammering test system for improving accuracy for detecting internal defects, by selectively receiving an acoustic wave generated, in response to impact given to a inspected object.
The hammering test system is provided with a hammer for hitting the inspected object, and a defect-detecting apparatus using a microphone surrounded by a hood, collecting the impact sound generated from the inspected object, when the inspected object is hit by the hammer and detecting the defects in the inspected object, based on an impact sound signal obtained by collecting the sound. The hood is formed with an internal space with a sound-reflecting inner wall having a pivoting surface profile, an opening at the front end and a focus at the back of the opening and located on the opening side. A sound-absorbing material is disposed opposite to the opening of the sound reflecting internal wall, and a sound-receiving face of the microphone is located inside the sound reflecting internal wall and is oriented toward the opening.
TAMANOI YOSHIHITO
TERAJIMA SHINSUKE
YAMATAKE CORP
Yoshio Kosugi