| 摘要 |
PURPOSE:To enable highly accurate detection of a weld line by keeping the amount of received light of a position detecting sensor to a fixed value or more, and feeding back and controlling the position of a light source against a condenser lens on the optical axis. CONSTITUTION:A sensor unit 12 is rocked in an X-direction by a rocking device and an image of scattered light from an irradiation point on an object 11 to be welded is formed on a position controlling sensor 17 by an image forming lens 16. The output from the sensor is amplified and calculated by a controller incorporated in a CPU, and converted to the distance L from the sensor unit 12. The position detection is calculated by driving the rocking device by a synchronizing signal sent from the CPU. The position of spot light at the irradiation point is measured successively, and the image of groove form is recognized as continuation of spot light, i.e. points. Detection of a weld line, i.e. a groove gap and the position of the center of gap, is outputted at each scanning by calculation using the CPU. |
