自动变速箱壳体压铸模设计

Die Design of Automatic Gearbox Shell

本文系统地阐述了大型复杂压铸件自动变速箱壳体的工艺开发、模具设计、调试生产的整个过程,重点介绍了模具设计过程理论数据的分析和模具结构设计。模具三维设计及二维设计应用PTC/Creo,整套模具设计全部实现参数化,确保了工程更改的前后一致性,三维结构运用模拟装配和干涉检查,确保设计间隙,铸造工艺过程采用MAGMA进行CAE分析,不断完善优化充型和凝固过程。该模具为超大型复杂模具,采用四个对角方向定位,避免高温高压下模具受热变形引起定位不准,同时改用方导柱代替圆导柱导向,避免合模拉伤;采用水冷方式和油温加热方式控制模具温度,提高铸件质量,保证压铸生产的连续性和稳定性;对金属液末端及最后凝固的厚大部分采用局部挤压技术,降低缩孔缺陷,提高组织致密性;采用真空压铸的方式减少铸件内部气孔;同时采用复合式感应液压缸抽芯,提高生产效率。

The process development,mold design and production of the large-scale complex die-casting automatic gearbox shell were introduced. Special emphasis was on the analysis of theoretical datas and the design of mold structure in the process of die design. The Pro/E5.0 software was used in the 3 D die design and 2 D die design. The parametrical design of the die was realized to ensure the consistency of the engineering changes. To insure the design gap,the assembly simulation and interference checking of were used in the 3 D die structure. To constantly improve and optimize the filling and solidifying process,the MAGMA software was used to analyzed the casting process. Due to the oversized and complex gearbox shell die casting mold,the four diagonal direction positioning was used to avoid inaccurate positioning caused by mold deformation at high temperature and pressure. Meanwhile,the square guide pillar was used to avoid drawing damage during die closing instead of circular guide pillar guide. The mold temperature was controlled using water cooling and oil heating method to improve the quality of castings and ensure the continuity and stability of die-casting production. The local extrusion technology was used at the end of metal liquid and the heavy section of final solidification to reduce shrinkage defect and improve the density. The vacuum die-casting was used to reduce the internal porosity of the casting.At the same time,the compound induction hydraulic cylinder core pulling was used to enhance the productivity.