Original paper(Vol.47 No.12 pp.1286)

Eigenfrequency analysis method of sandwich injection moldings

Tanimoto Yasuhiro; Nishiwaki Tsuyoshi; Tange Akio; Fujita Akihiro; Maekawa Zen-ichiro

Abstract:The purpose of this study is to propose a new numerical modeling of sandwich injection moldings, in which two kinds of materials are sequentially injected from one gate with a time lag. Using this molding method, the skin and core layers can be set in same injection, respectively. The materials of excellent mechanical properties can be produced by this method in comparison with the uniform plastic. The numerical proposed model in this study consists of shell and beam elements, corresponding to skin and core layers, respectively. The validity of the new numerical model for the eigenvibration analysis of sandwich injection moldings is checked through comparisons with experimental results. Using this model, influences of skin layer properties and core area ratios upon eigenfrequency are discussed. The results indicate that the validity of the new numerical model was verified through comparisons with experimental results.

Key Words:numerical model, eigenfrequency, sandwich injection moldings, shear deformation