Optimising the operation of servomechanical force systems used in the joining of thin-walled metal elements in the automotive industry

This article is concerned with controlling a servomechanical force system applied in the joining of thin-walled metal elements when manufacturing e.g. car bodies. The new, i.e. servomechanical electrode force control system is both an element and a parameter of a technology used for joining metal elements by means of resistance welding. The projection welding of 1.5 mm thick DX53 sheets was used to exemplify differences between the two i.e. pneumatic (classical) and servomechanical welding machine electrode force systems. An innovative solution applied in the servomechanical force system consists in using a hybrid algorithm in order to control the force and travel of welding machine electrodes during welding. The article presents the optimisation of the new, i.e. servomechanical electrode travel system being an alternative to the classical, i.e. pneumatic electrode force control system. As a result of the undertaken optimisation it was possible to increase the repeatability of a welding process and improve the quality of joints.