Research On Innovative Mould Board Of Injection Machine And Development Of Its Parametric Design System

Mould boards are the primary parts of injection machines. Moulds are installed on mould boards, and the performance of mould boards affects the quality of plastic products very much. Mould board is main part to use steel on, and its weight is about 70% of injection machine. The weight reduction of mould boards will cut cost of company and the quality advance of them will enhance products' competitive ability. So, Corporations of injection machines concern design of mould board.Present mould board design methods are outdated. The design of mould board depends on designer's experience or is checked by simplified formula calculation. So big safety coefficient is used to ensure the structure 's safety performance, and this results in havey and huge mould board structure. Often there are some problems in mould boards such as local stress concentration, too big deformation, and even structure fracture. And the performance of mould boards can't be ensured. So it needs to introduce scientific design methods into mould board desgin process.Focusing on this aim, there were some research done below:1) Collected now mould board design research information, and summarized structure FEA (Finite element analysis) theories such as contact theory, topology optimization theroy and parametr optimization theroy.2) Selected HTF530 mould board as research object, did three different analysis and compared the analysis results. Did experiment to check the analysis result. Used sequential optimization design method to optimize front and rear mould boards, and got new topological strcuture and better performance front and rear mould boards. According to this innovative topological structure, constructed and parametrically optimized mould boards of HTF80 to HTF3600.In order to use innovative mould boards to injection machines, and to fast design new mould boards for Haitian Group, need to develop mould board parametric design CAD system which can fast construct 3-D models of different dimension mould boards of different injection machine, and all the mould boards have similar structure. This can reduce workload of designers, shorten product development period and cut product costs. Some works were done to develop the parametric design system:1) Established database to store all optimized models' dimensions.2) Researched software development techniques based on UG, and established mould board parametric model and parametric drive mechanism.3) Developed mould board paratric design software.This research subject was a part of the cooperation project held by Institute of Manufacturing Engineering of Zhejiang University and Ningbo Haitian Group Co., Ltd. The mould board paratric design software is being used in Ningbo Haitian Group Co., Ltd. The innovative structures have been used to new injection machines. Experts group has authenticated this research subject in November 2005. So, the production has been validated and benefited the company.