| 摘要 |
PURPOSE:To automatically make a torch profile along a weld line without using a complicated mechanical position detecting means, by detecting electrically the shift of a target position of the torch, even if welding is executed by setting high the welding speed and oscillating speed, in case of consumable electrode type pulse arc welding. CONSTITUTION:Consumable electrode type pulse welding is executed by oscillating a torch 1 in the width direction of a groove 4, and the oscillating center of the torch is made to profile a weld line. In this case, detecting circuits 6, 12 output an arc voltage detecting signal Va, and a torch position signal Vt, respectively. Also, an arithmetic means 25 calculates the absolute value of a difference between the maximum value Vmax and the minimum value Vmin of a peak value of the signal Va which is detected in a period of one cycle of oscillation of the torch, which is derived, based on the signal Vt, as the variation quantity DELTAV of an arc voltage. Next, based on a correlation between the quantity DELTAV and a shift from the correct position of a target position of the torch 1, said shift quantity of the torch corresponding to the quantity DELTAt is calculated. From this shift quantity, a torch position correcting quantity is calculated, and the target position of the torch is corrected by its correcting quantity. |
