| 摘要 |
<p>A resistance-welding unit (1), particularly for high-current welding, comprising an inverter (2) which is powered by a three-phase electric power source (3) and is adapted to provide in output an AC voltage whose frequency is preset by welding control means; the inverter (2) is series-connected to a first step-down transformer (5) whose output terminals are connected to current rectifier means (6) for supplying, through first conductors (7a,7b), a first welding gun (7); the welding unit further comprising selector means (8) which are arranged between the inverter (2) and the first step-down transformer (5) in order to supply power to a second welding gun (11) which accommodates electric means (12,14) which are adapted to supply a DC current to the second welding gun (11). <IMAGE></p> |
