| 摘要 |
PURPOSE:To always position a backing metal in an exact place, by providing separately a welding machine and a backing metal driving device on both side faces of a base metal, and making the welding machine and the driving device run remotely and synchronously by only a signal going and coming between the surface side and the reverse side of the base metal. CONSTITUTION:A transmitter 2 is fitted to a welding machine 1 of the surface side of a base metal 13, and a receiver 5 is provided on a driving device 4 of a backing device 6 of the reverse side of the base metal 13. When a signal transmitted from the transmitter 2 is received by the receiver 5, the driving device 4 operates, and the backing device 6 runs in a state that it is positioned just in front of a welding arc 12. In this way, the backing device 6 can be positioned in an exact place without being influenced even if irregularity of the groove or tack welding exists to some extent. |
