| 摘要 |
PURPOSE:To easily obtain a determined result with high reliability in a short time on a welded result or the welding quality. CONSTITUTION:A weld zone W is irradiated with a laser beam LB from a beam emitting unit 12 of a laser beam irradiating device 15, by which both metals (materials to be welded) 16 and 18 are molten and solidified, and joined mutually at that place. A part RB of infrared rays emitted from the vicinity of the weld zone W of the material 16 to be welded is made incident on a light receiving part 22 of an infrared sensor 20 through an optical filter 24, sent to a photoelectric conversion part 28 via an optical fiber 26 and converted into an electrical signal (temperature detection signal) TS here. In the determining device 34, a value (TS) of the temperature detection signal TS is compared with a reference value AS at a point of time after the lape of a specified time from the irradiation starting time or the irradiation completion time of the laser beam LB in a comparison part 32 and the determined result DS of the welding quality in accordance with a logical state of a compared result signal CO from the comparison part 32 is outputted from a determination output part 36. |
