Optimization of the Plastic Injection Molding Parameters by Using the Taguchi Method to Prevent Jammed Components in the Assembly Process of Mechatronic Devices

摘要

Mechatronic devices are more and more present in the automobile industry, with roles, to support the control of the car or to interact with the entire system to make the driving safe and to increase passengers comfort. If in the past these devices were simple, used for tasks such as actuation of the door opening or other similar servo-mechanisms, nowadays, they consist of a combination of a printed circuit board, including microprocessors and software, but also mechanical and plastic parts working in complement with each other to reach a common purpose. Often, the small plastic parts are designed to be used in devices for translation, rotation or both movements, and subsequently the haptic feedback feeling associated to these is important to be kept within the requested range. This paper presents the optimization of the plastic injection molding parameters, by using Taguchi method in order to reduce risks in the serial production parts with dimensional precision. Also, the optimization method is targeting prevention of jammed components in the assembly process, and parts with changed roughness of the surface that could lead to a friction or a bad haptic feeling. The study is performed on a plastic material component obtained from polypropylene (PP) and the chosen parameters are modeled with an orthogonal array (OA), signal-to-noise (S/N) ratio and analysis of variance (ANOVA). They will be applied to analyze the shrinkage effect on the molded parts. The Minitab software will be used to support the design of the experiments based on the aforementioned factors, determine the number of necessary trials, and analyze variance used to determine the parameters that affect the quality of the mentioned characteristics. The results will show the best combination of parameters with optimal interaction to be used in injection molding in order to supply plastic parts for a reliable assembly process of the mechatronic devices.