Device for monitoring welding process of spot welding device comprises current measuring unit, voltage measuring unit, analogue-to-digital converters, processing unit, and output unit

摘要

A device comprises a current measuring unit (21) for measuring the electric current between the electrodes of the welding device; a voltage measuring unit (22) for measuring the voltage between the electrodes; analogue-to-digital converters (31, 32) to convert the measured current and voltage signals into a digital current and a digital voltage. Device also has a processing unit (40) for calculating the electrical impedance between the electrodes; and an output unit (50) for outputting the electrical impedance of the processing unit. An Independent claim is also included for a process for monitoring a welding process. Preferred Features: The device further comprises a data analyzer for comparing the electrical impedance with historical data stored in a storage unit, the historical data being based on different quality results of a spot welding process.