三轴数控平面磨床几何精度分析与稳健设计

为了经济合理地分配三轴数控平面磨床零部件几何精度,提出了一种几何精度分析设计的方法.针对磨床具体结构,基于多体系统理论和齐次坐标变换方法,建立了磨床几何误差传递模型,并通过试验验证了该模型具有理想的预测性能;根据误差传递模型,运用正交试验设计和参数试验的试验设计方法分析识别了影响磨床加工精度的11项关键几何误差因素;基于稳健设计理论,在成本分析和误差溯源基础上,建立了11项关键几何误差因素下的磨床成本-质量模型,并运用该模型对关键几何误差因素的公差进行了稳健设计.研究结果表明:上述方法能实现对磨床几何精度的经济合理的分配.

Analysis and Robust Design of Geometric Accuracy of a Three-axis CNC Surface Grinding Machine

In order to distribute the geometric errors of parts economically and reasonably, a method for the analysis and design of geometric accuracy was proposed. According to the specific structure of a three-axis CNC surface grinding machine, a geometric error propagation model including 21 parameters was established on the basis of multi-body system theory and homogeneous coordinate transformation method. The model was verified and it had ideal prediction accuracy. Key geometric errors were analyzed by using orthogonal design and parameter test of DOE methods. After cost analysis and error tracing, a cost-quality model for key geometric error variables was established on the basis of robust design theory. At last, the tolerances of key geometric error variables were distributed according to this model. The results have shown that the methods mentioned above are effective in the distribution of the geometric accuracy of grinding machine.