| 摘要 |
PURPOSE:To detect defective adhered parts accurately by hammering the adhered matter of adherends and detecting the time interval of the output of a piezoelectric element on the hammer generated at this time. CONSTITUTION:The top surface of the adhered part of adherends 1, 2 consisting of metallic plates or the like is tapped with a hammer 6 provided with a piezoelectric element 9 on a hammering head 7. The output of the element 8 is inputted via a preamplifier to a waveform shaping circuit, by which it is converted to a square wave. In a decision circuit, the time interval (t) of the square wave is compared with the threshold value tO corresponding to the time interval of the piezoelectric output in a normal adhered part. If foam or other defective adhered part 4 exists in the part 3, the time is t>tO, and this is decided as a defective adhered part and is displayed in a display device. Thereby, the adhered state is inspected extremely easily and accurately. |
