Optimization of Ejector Pin Configuration for Plastic Base based on Moldflow and Workbench and Its Design of Eccentric Injection Mould
Lin Quan, Chen Lijun, Chen Lian, Lin Xin, Zhang Daoping
School of Mechanical and Electrical Engineering, Wuyi University, Wuyishan 354300, China
Abstract：In order to solve the problem of serious demoulding deformation of injection molded parts due to improper ejector pin design of injection mould, taking a plastic base part as example, molding shrinkage and warpage analysis and demoulding analysis were done through Moldflow combined with Workbench, and the warping deformation characteristics of plastic shrinkage that hindered the demoulding and distribution of the part strain and deformation caused by demoulding resistance were obtained, which provided basis for the optimization of ejector pin configuration. Finally, six ejector pins were set up in the area of significant demoulding resistance and the scheme of three ejection inserts with the ejector pins was established in the area of relatively large strain in the demoulding analysis. Based on the Moldflow analysis and ejector pin configuration, an eccentric injection mould with lateral feeding was adopted for the plastic part, while snap-fit structures of the plastic part were molded by angle ejector for inner pulling and angle pin for outer pulling to effectively solve the quality problems resulted from base molding. It was proved in practice that this method could realize the design process of ejector mechanism of injection mould with data, discover and solve problems before mould manufacturing, and improve design accuracy of ejector mechanism, shorten the research and development cycle, and provide reference for other similar injection mould design.
Keywords：base; Moldflow; Workbench; injection mould; ejector pin; demould
Lin Quan，Chen Lijun，Chen Lian，et al. Optimization of ejector pin configuration for plastic base based on moldflow and workbench and its design of eccentric injection mould[J]. Engineering Plastics Application，2020，48(5)：103-108.