WELDING METHOD USING AREA SENSOR

PURPOSE: To obtain a welding method in which a weld line can be detected with good accuracy and stably and in which a high-quality welding operation can be performed with high accuracy even in surroundings in which an external situation is changed like in actual site, in an area sensor visual system in an automatic welding operation. CONSTITUTION: A work which is composed of a steel pipe Pi, a plate Pl and a ring Ri is set so that the plate is tilted at 45 deg., an area sensor 1 is arranged just above to face a fillet weld joint part (w), an illuminator 2 is set at an angle θ of 30 deg. or lower from the plate Pl, and the image of the weld line, a welding starting point or a welding finish point at the weld joint part (w) is picked up, an image signal from the area sensor 1 is image-processed by using the Hough transformation, and a welding torch is controlled on the basis of obtained information on the weld line. By means of the Hough transformation, an end point such as the weld line, the welding starting point or the like can be detected surely and with good accuracy from an image which contains many noises.