CLOSED LOOP FUZZY CONTROL OF PART WEIGHT IN INJECTION MOLDING OF LIQUID SILICONE RUBBER (LSR) BASED ON PVT-BEHAVIOR

摘要

The injection molding of Liquid Silicone Rubber (LSR) represents a cost-efficient process for the production of high quality elastomer moldings. Due to the extreme thermal conditions in the mold and the low material viscosity a precise undervolumetric filling of the cavity is required to avoid underfilling or flash formation. Since process disturbances lead to changes in the mass of material injected into the mold a closed loop control of the injected mass based on the pvT-behavior is developed and realized on an industrial injection molding machine. Dependent on the course of the cavity pressure and the mold temperature a fuzzy-based algorithm determines the required changes of the dosing volume in case of process disturbances.