冲压件扭转与回弹问题研究与测量方法

乘用车冲压单件尺寸检查时,常用到三坐标设备及测量支具。因为车身外覆盖件直接对车身外观有重要影响,所以车身外覆盖件的型面尺寸有很高的精度要求。外覆盖单件具有材料薄、无加强支撑件等特点,所以在使用三坐标测量时,零件自身重力、零件回弹以及支具支撑和夹紧方式对测量结果都有非常大的影响。文章通过重复性实验、设计不同夹紧方式及顺序等方法,以后备箱内板的三坐标测量为例,给出针对不同冲压零件问题的测量解决方案。同时归纳总结了影响测量结果的主要因素,阐述了如何分析真实的零件状态,并指导模具优化的通用经验方法。

Research the Measurement Methods of Twist and Spring Back of Stamping Parts

CMM equipment and measurement fixture are commonly used when checking the dimensions of stamping parts for passenger vehicles.Because the outer stamping part has a great influence on the appearance of the car body.And the profile size of the outer stamping parts have a high precision requirement.They has the characteristics of thin material and no reinforcement support.Therefore,when using the CMM measurement,the weight of the part,the spring back of the part,and the support and clamping method of the fixture have a great influence on the measurement result.In this paper,making the repeated experiments,designing different clamping methods and sequences,the CMM measurement of the trunk lid inner plate was taken as an example.And the measurement solutions for the problems of different stamping parts are given.At the same time,it summarized the main factors affecting the measurement results,and explained how to analyze the real part status.The paper also gave the general method of mold optimization.