WELDING POWER SOURCE AND TACK WELDING METHOD

• Main Author: TONG HONGJUN
• Format: Patent
• Language: English
• Published: 27.03.2014
• Subjects: CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; SOLDERING OR UNSOLDERING; TRANSPORTING; WELDING; WORKING BY LASER BEAM

PROBLEM TO BE SOLVED: To provide a welding power source and a tack welding method capable of properly setting the ejection length of a welding wire 1, even if a welding torch 4 is pulled up from a base material 2, when stopping welding in a temporary tacking position of tack welding.SOLUTION: A power source main circuit PM of the welding power source PS supplies electric power between the welding torch 4 and the base material 2, and a feeding speed control circuit FC controls a feeding speed of the welding wire 1, and a current drop reference value setting circuit ITN sets a current drop reference value Itn being a reduction value of a welding current when pulling up the welding torch 4 from the base material 2 when finishing the welding in the temporary tacking position. A welding stopping discriminating circuit ND discriminates that the welding is finished when the welding torch 4 separates from the base material 2 when a current smoothing value Iav reaches the current drop reference value Itn, and outputs an output stopping command to the power source main circuit PM, and outputs a feeding stopping command to the feeding speed control circuit FC. As a result of this, a welding defect is not caused.