| 摘要 |
PROBLEM TO BE SOLVED: To accurately detect a welding position inside a groove even under an environment with a large disturbance factor of electromagnetic noise or the like, to make a welding torch accurately follow the groove, and to make welding heat input to the groove stable and accurate.SOLUTION: A penetration bead temperature detector includes: an element column holding means (6) which has an optical element column in which a plurality of optical elements composed of the combination of FBG optical fibers (FBG1L-FBGnL/FBG1R-FBGnR/FBG1C-FBGnC) for reflecting the light of a wavelength corresponding to a temperature and optical couplers (PH-1L to PH-nL/PH-1R to PH-nR/PH-1C to PH-nC) for giving incident light to the FBG optical fibers and outputting reflected light of the FBG optical fibers in one line, and places the optical element column at a prescribed distance from the bottom of a groove in parallel with the groove on a surface on the back side, that is, a back surface, of a surface that the welding torch faces of a welding object material with the groove formed thereon; and conversion means (32, 35/33, 36/34, 41) for converting reflected light output of the respective optical couplers to temperature detection signals at positions away from the holding means (6). |
