| 摘要 |
<p>Out of the welding operations carried out by a welding robot, a multi-layer buildup welding operation is a very important operation since it enables the strength of a weld zone to be secured but it has many technical difficulties. In order to carry out the first-layer welding according to the present invention, an approximate straight line or an approximate curve between taught points is determined on the basis of coordinates values through which a welding torch actually passes between the taught points, and points on the approximate straight line or approximate curve are computed on the basis of the distances of the taught points, each actual welding pass being then defined by these points. Regarding the loci in the welding from the second-layer welding onward, the direction and quantity of shift are determined by carrying out computation on the basis of the two points taught as the welding starting and ending points during the teaching for the first-layer welding and the two reference points designated for the purpose of defining the direction of shift. The multi-layer buidup welding iscarried out after computing the loci of operations for the welding from the second-layer welding onward in this manner. In order to control the posture of the welding torch during the welding from the second-layer welding onward, the loci of operations therein are determined on the basis of the locus of operation of the welding torch during the first-layer welding and the angle of rotation given from the outside of the welding torch, and the welding torch is then turned by a given angle around a vector of direction of advance determined at a taught point, the posture data being computed. The welding from the second-layer welding onward is carried out on the basis of the posture data thus determined. Thus the first-layer welding and the subsequent welding runs, i.e. a multi-layer buildup welding can be carried out with a high accuracy owing to these operations.</p> |
