| 主权项 |
1. A method of drawn arc welding a stud simultaneously to a first workpiece and a second workpiece, with the first workpiece affixed to the second workpiece and with an electrically insulating joining layer between the first and second workpieces, the method comprising the steps of:
(a) boring a cavity through the first workpiece, the joining layer and only a portion of the second workpiece; (b) connecting a first electrode from a first output of a power supply to the stud; (c) connecting a first lead to the first workpiece, the first lead electrically connected via a first diode, having a first electrical orientation, to a second output of the power supply; (d) connecting a second lead to the second workpiece, the second lead electrically connected via a second diode, having a second electrical orientation opposite to the first electrical orientation, to the second output of the power supply; (e) pressing the stud into the cavity into contact with the first workpiece and the second workpiece; (f) activating the power supply to apply a pilot arc; (g) moving the stud away from the first and second workpieces to simultaneously form a first arc between the stud and the first workpiece and a second arc between the stud and the second workpiece; (h) increasing the power output from the power supply so as to cause the surfaces of the first and second workpieces in the cavity to partially melt; and (i) pressing the stud into the partially melted surfaces to thereby simultaneously weld the stud to the first workpiece and the second workpiece. |
