| 摘要 |
PURPOSE:To provide a monitoring device for a welding state with high reliability to perform a laser welding working with reproducibility and a high quality. CONSTITUTION:The device is equipped with a photodetector 7 monitoring direct light 11 before an object to be worked 13 is irradiated by a laser beam 10 for welding working and outputting a monitor output 15 showing the secular change of optical intensity, which is the result of the monitoring, and a photodetector 8 monitoring reflected light 12 after the object 13 is irradiated with the laser beam 10 and outputting a monitor output 16 showing the secular change of optical intensity, which is the result of the monitoring. And, the device is also equipped with a comparing part 9 judging a welding state in the object 13 according to a monitor output 15 to be outputted from the photodetector 7 and a monitor output 16 to be outputted from the photodetector 8, and the acceptable or the nonacceptable of a welding state is judged from the secular change of the absorption factor of the laser beam 10 in the object 13. |
