| 摘要 |
PURPOSE:To enable the discrimination of the quality in welding easily simultaneously with the welding by measuring the temp. at the welding point based on the infrared ray having the frequency zone excepting the laser frequency zone by the infrared ray reflected by a dichroic mirror. CONSTITUTION:A laser beam 11 is irradiated from a laser irradiating means 10 and a heat welding is performed at a welding point 31. In this case, an infrared ray is generated at the welding point 3 and its periphery, the ray is condensed by an image forming lens 21 is condensed, totally reflected by primary mirror 50 and the visible ray among the reflected rays is imaged on the pickup face of an image pickup element 40 by passing through a dichroic mirror 60. On the other hand, the infrafed ray among the reflecting ray reflected at the welding point 31 is reflected by the mirror 60 and imaged on the end face 61a of optical fiber 61. The imaged ray is send to an infrared ray sensor 70 through the optical fiber 61, detecting the surface temp. in laser beam welding based on the infrared ray in the frequency zone excepting the frequency zone of the laser beam 11 among the received infrared rays and outputs the signal corresponding to the temp. thereof. A discriminating means 80 outputs a good welding signal only in case of the surface temp. being more than the prescribed value. |
