Design Method Of Injection Mold Cavity Based On Numerical Analysis And Reverse Deformation

Molds/dies are significant technical equipments of producing various industrial products. In modern industry, about 60%～90% products are manufactured by molds. In the past, because of many reasons, the accuracy of the mold is not high, most of them belong to common level, only small part of them belong to high level. With the development of manufacture, improving the dimensional accuracy of plastic part is becoming a big job.With the development of mold, computer aided engineering (CAE) technique is becoming more and more popular in plastic mold industry. In injection mold industry, CAE can predict injection process. But the use of CAE is concentrated on optimizing process parameters. Therefore the parameters are interrelated and interacted with each other, so this way can eliminate warp.Reverse deformation technique is a useful way to solve the problem of warp. Analyze of the product's warp, Process the mold by reverse deformation technique. Then realize the target of improving the accuracy of the product. But the use of reverse deformation technique is just on product with simple structure, not the precise mold/die with complicated structure, and not consider about the requirement of formation process.Reverse Engineering (RE) originate from precision measurement and quality inspection. The design is from backward position to advanced position. Different from tradition design course, it studies the product, substance or picture and then realize CAD construction.The thesis is concerned mainly on the project of "The digitized manufacture of car's large precise complex injection mold", which is a key industries project of the Guangdong province. Numerical analysis technique and reverse deformation technique and reverse engineering are introduced to solve the warp problem of plastic part. The contents of this paper includes is as follows:(1) Get reverse-deformed model form origin model, obtain the biggest warp of the optimized point cloud, fix the optimizing reverse coefficient and discover some rules about reverse deformation.(2) Realize point cloud model and triangle sheet model's construction in UG through VBS programming and UG's development tool UG/OPEN GRIP. (3) Evaluate the reverse engineering model through Imageware to make sure the accuracy of the model.(4) Design the mold based on the reverse-deformed product.According to the study, effective reverse deformation method is got, effective reverse deformation cofficient is fixed, rules about reverse deformation are discovered. On reverse engineering, realize triangle sheet auto model construction and realize manual model construction by using the reverse engineering function of UG. And in the end, Imageware is used to inspect the accuracy of the model. The result prove that: reverse deformation can reduce the warp efficiently. The solution of warp means a lot on improving the quality of plastic part and widening the use of plastic part in our life.