【作者】 商鹏；

【导师】 张大卫；

【作者基本信息】 天津大学 ， 机械制造及其自动化， 2008， 博士

【摘要】 装配有高速电主轴与直线电机的现代高速机床的热误差检测是当前业内的研究热点问题,尤其电主轴热漂移误差的检测是广受关注的难点问题。结合五轴高速加工中心误差检测项目,本论文研究了转动轴误差检测方法、一体式电主轴系统、直线电机驱动系统热误差检测方法等现代高端机床精度检测难点问题,建立了加工中心综合误差数学模型,完成了对电主轴系统、直线电机系统的有限元热分析,并完成基于球杆仪的机床综合误差检测试验。取得的主要研究成果如下:基于齐次坐标变换原理,建立了基于球杆仪检测原理的综合误差模型,该模型包含对加工精度影响较大的工作台旋转轴C轴的四项安装定位误差,主轴热漂移误差,以及直线电机驱动下的三直轴各项几何误差与热误差,据此模型,提出了基于球杆仪测量原理的误差检测方法;基于有限元热分析方法,借助商用软件ANSYS的热分析模块完成了机床整体温度场分布,主轴与直线导轨热变形的有限元分析,得出了主轴的三种可能热变形模式与直线导轨的热变形模式;构建了针对高速五轴机床的主要误差元素的球杆仪检测模式,完成了各检测模式的球杆仪检测轨迹仿真,据此得出工作台旋转轴C轴的四项安装定位误差、主轴热漂移误差以及直线电机驱动下的三直轴各项几何误差与热误差的球杆仪圆轨迹特征;根据机床运动传递链的封闭性原理,提出了基于球杆仪测量数据的几何误差与热误差分离方法,并应用最小二乘法提出了球杆仪自身安装定位误差的分离方法,提高了检测精度;综合球杆仪检测数据,绘制主轴热漂移规律曲线,直线导轨上不同位置处热变形规律曲线,并得到出现热误差前后工作空间内工作台平面上的综合误差分布变化规律,提出了机床精度评价方法。本文工作对我国高端机床的自主开发及精度提高有重要实用价值,并且本文提出的误差分析检测方法适用于类似结构的五轴机床和高速机床。更多还原

【Abstract】 This paper aimed at the measurment of the main errors of the 5-axis high speed machine tools, and foused on the key problems concernd for the measurement methods of the errors of rotary axis, the thermal errors of high speed spindle and linear motor systems. This paper based on double-ball-bar(DBB) theory and found the mathematic model including main geometrical errors and thermal errors of the 5-axis machine tools; and thermal-structure coupling analysis for high spindle and linear motor systems was done. Five DBB measurement models were designed for different errors. Lastly, the experiments of DBB for 5-axis machine tools were done. The following in-depth work had been completed.The synthesis error model of high speed 5-axis machine tools was founded based on homogeneous coordinate transformation theory, included 4 geometrical errors of C-aixs, thermal drift errors of high speed spindle and geometrical and thermal errors of linear motor systems, then the DBB measurement method was founded according to the error model.The FEA analysis for whole machine tools, high speed spindle and linear guide was done by ANSYS, the temperature field of machine tools, the thermal distortion of spindle and linear guide were got, by applying thermal and structural loads on the FEA models.The measurement models of DBB was founded and different trajectories of DBB for different errors were simulated, including 4 geometrical errors of C-aixs, thermal drift errors of high speed spindle and geometrical and thermal errors of linear motor systems.The method for separating the geometrical and thermal errors from DBB data was proposed based on the closed characteristic of the kinematical chain of 5-axis machine tools, the location errors of DBB could also be separated by using least square method.At last, the variation curves of spindle thermal drifting errors and thermal errrors of linear guide were drawn, and the distribution on the worktable surface of synthesis errors were also drawn, then the accuracy of the machine tools was evaluated based on all the analysis mentioned above.The outcome of this research had high value for the development of high performance mahine tools, and the methods proposed in the paper were also suitable for the other similar 5-axis and high speed machine tools.更多还原