Multiple-Sensor Monitor Resistance Spot Welding Process

Multiple-sensor Synchronous data collection system was developed on the base of RS485 distributed single-chip and the sensors of resistance spot welding current, voltage, electrode displacement and electrode pressure met spot welding process real time monitoring. The results show that the incomplete fusion defects of aluminum alloy pulse spot weld can be judged by the electrode displacement range and electrode pressure range. When the expulsion appear in spot weld, the pulse of electrode displacement turn sharp down, and the voltage signal exhibit notching curve, and the electrode pressure signal exhibits high-frequency impulse. The impulse amplitude and duration are corresponding to the expulsion extent. Therefore, defects of the expulsion in spot weld can be judged by the characteristic information.