The functional evaluation of injection molding processes has often been dealt with in quality engineering, but there have been few attempts to evaluate the injection molding machine itself. This study aims at optimization of the plasticizing unit, a sub-system of an injection molding machine. We studied a method in which an ideal relation between plasticizing unit workload and amount of energy consumed is defined as the generic function and supply voltage is used as a noise factor. As a result, we were able to obtain high reproducibility of the gain, showing that this evaluation method is correct. We also evaluated target functions and attempted to reach target values, and were able to find useful means for evaluating the functionality of an injection molding machine.
