中文摘要：

为提高数控机床整机可靠度，基于赫兹接触理论，对单螺母滚珠丝杠副静刚度可靠性及灵敏度进行研究，利用单螺母滚珠丝杠副的导程、接触角、丝杠公称直径、滚道曲率比、工作载荷等技术参数建立了轴向接触变形的理论模型。根据滚珠丝杠副的轴向接触变形小于加工精度的原则，建立滚珠丝杠副可靠性模型。利用改进一次二阶矩法分析和计算单螺母滚珠丝杠副的可靠度和灵敏度。结果表明：适当增大滚珠丝杠副的导程以及减小滚道曲率比可提高滚珠丝杠副的刚度，减小工作载荷可以降低滚珠丝杠副的轴向接触变形，提高滚珠丝杠副的可靠度。

英文摘要：

To improve the reliability of numerical-controlled machine tool, the reliability and sensitivity of static stiffness of single nut ball screw pair were studied. Based on the Hertz Contact Theory, a model of axial contact deformation was established using the lead, contact angle, nominal diameter of ball screw, raceway curvature ratio, working load and other technical parameters of single nut ball screw pair. According to the principle that the inaccuracy of axial contact deformation for nut ball screw pair is less than the machining accuracy, a nut ball screw pair reliability model was established. The reliability and sensitivity of single nut ball screw pair were analyzed and calculated using the modified first order second moment method. The results show that the static stiffness of nut ball screw pair can be improved by increasing the lead of nut ball screw and decreasing the raceway curvature ratio appropriately, and the reliability of nut ball screw pair can be improved by decreasing the working load to reduce axial contact deformation of nut ball screw pair.