| 摘要 |
PURPOSE:To obtain good welding in compliance with welding conditions by maintaining the output voltage and output current of a welding power source in automatic arc welding at adequate values. CONSTITUTION:Static output characteristics of a welding power source, that is, the relations between output voltage VA and output current IA and between set voltage VS and set current IS which are arbitrary set values are automatically controlled in such a way that the equationIholds near the arbitrary set values. The function F1 contained in the equationIis so selected as to satisfy each of the equation II. Now, when the voltage VA changes to a deviation V'A1 higher than the set voltage VS, the current IA decreases to a deviated value I'A1 instantaneously and the point at the set conditions P moves to a deviated point P'A1. Since the melting speed of a welding wire decreases as well, the arc length decreases and the welding current increases to recover the original set condition point P. When the voltage VA drops below the set voltage VS, the voltage is reset to the set condition point P by the reverse effect. |
