| 摘要 |
PROBLEM TO BE SOLVED: To reduce welding time and to control welding speed arbitrarily by using an inverter type DC power source which supplies a DC current consisting of a pair of positive and negative pulses during the time for energizing a welding zone. SOLUTION: A weld zone of a package is welded by roller electrodes to which a current is supplied from an inverter type DC welding power source. The weld zone is energized by a welding current of total 1ms with a pair of positive and negative pulses for each spot 34 for welding, while the length of the welded place, namely the nugget 35, is about 0.2mm. Then, this nugget 35 is cooled for 2ms. Accordingly, it is possible to reduce the welding speed to one tenth compared with that of a conventional single phase DC welding power source. As a result, the inverter type DC welding power source enables various welding conditions to be arbitrarily controlled such as pulse width, welding current and pulse spacing; it is also capable of feedback control. |
