WELDED PORTION VISUALIZING METHOD AND DEVICE

摘要

To permit shadow-free observation of but-welded portion between welded materials different in plate thickness. A CCD camera (13) for shooting a welded portion (12) is provided within a vertical plane immediately above a beveling portion (11) where welded materials (10a, 10b) different in plate thickness is disposed abutting against each other so as to be tilted a specified angle from an observation object normal (14), a flash lamp (15) is provided within a vertical plane immediately above the beveling portion (11) and at an angular arrangement deviated ±10°-20° from an angular arrangement symmetrical to the CCD camera (13) with respect to the observation object normal (14) as an symmetrical axis, and an illuminating light is emitted from the flash lamp (15) disposed immediately above the beveling portion (11) to thereby remove the possibility of producing a shadow on the but-welded portion (12) between welded materials (10a, 10b) and prevent the specular reflection component of a high-brightness illuminating light to be applied to the welded portion (12) from the flash lamp (15) from being shone onto the CCD camera (13) strongly, whereby the image of the welded portion (12) with a brightness suitable for image processing is obtained.