Abstract: In order to study the key geometric errors affecting the machining accuracy of the large-sized gear hobbing machines, a method for identifying key geometric errors of the machine tool was proposed based on the tooth surface posture-geometric error model combined with Sobol method. Firstly, based on the theory of homogeneous coordinate transformation, the tool posture-geometric error model was established. By solving the two-parameter envelope equation of gear hobbing, the coordinate values of the contact trace points of the machined tooth surfaces were obtained, and the tooth surface posture-geometric error model was established. Then, considering the randomness and mutual coupling of geometric errors, the Sobol method was used to analyze the sensitivity of the model, and the sensitivity coefficients of geometric errors were calculated to identify the key geometric errors. Finally, the virtual simulation corrections and verification of the key geometric errors were performed. The results show that the proposed method may effectively identify the key error terms of the large-sized gear hobbing machines.

Key words:  , large-sized gear hobbing machine, tooth surface posture-geometric error, Sobol method, sensitivity analysis

摘要： 为研究影响大规格滚齿机加工精度的关键几何误差，提出了一种基于齿面位姿几何误差模型结合Sobol法的机床关键几何误差识别方法。首先，基于齐次坐标变换理论，建立了刀具位姿几何误差模型，通过求解滚齿双参数包络方程，获得了加工齿面接触迹点坐标值，建立了机床齿面位姿几何误差模型；然后，考虑几何误差的随机性和互耦性，利用Sobol法对该模型进行敏感性分析，计算了几何误差的敏感度系数以识别出关键几何误差；最后，进行了关键几何误差虚拟仿真修正和对比验证。研究结果表明，所提方法能有效识别大规格滚齿机的关键误差项。

关键词: 大规格滚齿机, 齿面位姿几何误差, Sobol法, 敏感性分析