电机线圈支架注塑成型过程模拟与低圆柱度优化方案探究

Study on Injection Molding Process Simulation and Low Cylindricity Optimization Scheme of Motor Coil Bracket

针对某15%玻纤增强聚对苯二甲酸丁二醇酯(PBT)材料的电机线圈支架,采用Moldflow模拟其注塑成型过程,得到翘曲变形结果,计算绕线区域的圆柱度并探究优化方案。基于默认工艺计算得到不同效应产生的翘曲变形,得出导致产品翘曲变形及影响圆柱度的最重要因素是收缩不均。针对收缩不均因素,设计五因素四水平的正交试验,模拟计算产品在不同工艺参数组合下的圆柱度。通过极差与方差分析得到各工艺参数对圆柱度的影响程度从大到小排序为:模具温度>熔体温度>保压时间>冷却时间>保压压力,对应的工艺参数组合为A_(3)B_(3)C_(2)D_(2)E_(4)。最优工艺参数组合下圆柱度为0.3347 mm,相比初始工艺降低43.5%,验证工艺优化对翘曲变形的改善效果。通过该优化工艺参数组合下的填充等值线、流动前沿温度、气穴和熔接线结果,结合实际试模产品状态,验证其应用于实际生产的可行性。

Moldflow was used to simulate the injection molding process of a 15% glass fiber reinforced polybutylene terephthalate(PBT)motor coil bracket,and the cylindricity of wire-wrapping area was analyzed according to the warpage deformation results.The results of warpage deformation using default process parameters show that the most important factor causing the warpage deformation and cylindricity is the uneven shrinkage.Orthogonal tests with five factor and four level were designed to calculate the cylindricity under different combination of process parameters.Through range and variance analysis,the influence degree of each process parameter on cylindricity is ranked as mould temperature>melt temperature>holding time>cooling time>and holding pressure.The combination of process parameters is A_(3)B_(3)C_(2)D_(2)E_(4).Through the optimal combination of process parameters,the minimum cylindricity is 0.3347 mm,which is 43.5% lower than that under the initial process parameters.The effect of parameters optimization is validated.By analyzing the result of product filling contours,flow front temperature,cavitation and the weld line,combing the mold-trial sample,the rationality of the optimization process parameter in injection molding was verified.