Patent ID: 8680423

Claim:
A spot welding gun for resistance-welding of workpieces, comprising: (a) first and second welding gun arms having first and second electrodes, respectively; (b) a drive for moving the welding gun arms, said drive comprising a spur wheel, a connecting rod, and a bearing assembly connecting the connecting rod with the spur wheel outside a central axis of the spur wheel; and (c) an element arranged between the connecting rod and the second welding gun arm to compensate for different thicknesses of the workpieces to be welded, said element comprising a casing including an eccentric shaft movably mounted in a bearing, as well as a blocking device; wherein the spur wheel is connected to the first welding gun arm on a first side of the spur wheel and the connecting rod is connected with the second welding gun arm on a second side of the spur wheel opposite the first side; wherein the compensation element allows the spur wheel to rotate without further building up pressure of the first and second electrodes on the workpieces in that the eccentric shaft is rotated about an axis after contact of the first and second welding gun arms with the workpieces without the second welding gun arm being caused to move; and wherein the bearing assembly performs a curvilinear movement during operation.