三维螺纹测量机接触式测头的优化设计

为削弱接触式测头对高精度三维螺纹测量机精度的影响，设计了一种接触式测头结构尺寸优化方案，并提出了相应的标定方法。通过有限元仿真和正交试验优化测头结构参数，确定最优结构参数；利用坐标变换理论和最小二乘法原理建立测头标定模型并进行了标定试验；通过不同预压量下的螺纹塞规对比试验及螺纹环规、塞规对比试验对优化后的测头进行测试。结果表明：接触式测头测量螺纹塞规、环规参数标准偏差在1 μm左右，满足三维螺纹综合测量机接触式测头测量精度要求。该优化方案及标定方法为测头结构设计提供了重要的理论基础。

Optimal Design of Contact Probes for Three-dimensionalThread Measuring Machines#br#

In order to reduce the influences of the contact probes on the accuracy of the high-precision three-dimensional thread measuring machines， an optimization plan for the structure and size of the contact probes was designed， and the corresponding calibration method was proposed. The structural parameters of the probes were optimized through finite element simulation and orthogonal experiments to determine the optimal structural parameters. The calibration model of the probes was established by the coordinate transformation theory and the principle of least square method and the calibration experiments were carried out. The optimized probes were tested through the screw plug gauge comparison experiments and the screw ring gauge and plug gauge comparison experiments under different preloads. The results show that the standard deviation of the parameters of the contact probe measuring thread plug gauge and ring gauge is about 1 μm， which meets the measurement accuracy requirements of the contact probes of the three-dimensional thread comprehensive measuring machines. The optimization scheme and calibration method provide important theoretical basis for the design of the probe structures.