A similarity-based approach for the variant design of core-pulling mechanism in injection mold design

Core-pulling mechanism plays a vital role in producing plastic products with complex shapes. However, the design of core-pulling mechanism is still excessively depended on experience. As a result, low intelligent input often leads to high costs and long lead-time. In this paper, we propose a similarity-based approach for the variant design of core-pulling mechanism in injection mold design. An assemble model supporting variant design is established as the foundation of the case repository of core-pulling mechanism. A hierarchical assessment algorithm, which calculate the synthetic similarity of four characteristic parameters, viz., core-pulling type, core-pulling force, core-pulling distance, and shape description, is proposed to evaluate the similarity among undercut features. On the basis of the retrieved case with the highest similarity to the undercut feature of new plastic product, geometric model modification is performed by fine-tuning and head feature generation algorithm, and assemble tree modification is finished by the structural descriptions for assemble frame and assemble information of parts. Finally, case study is provided to validate the feasibility and effectiveness of the proposed approach.