数控机床进给系统刚度所引起的失动量的大小在开环数控系统中直接影响机床控制精度 ,在闭环数控系统中过大的失动量会对系统稳定性产生影响。基于进给系统质量、弹簧力学模型 ,导出了进给系统传动刚度、进给系统扭转刚度对失动量影响的解析表达式以及相关参数选择的原则和计算式 ,并结合实例进行了分析计算。其目的是确保数控机床的加工精度 ,以便提高快速性、稳定性 ,减少稳态和动态误差 CNC machine tool feed system stiffness caused by the size of the loss in the open-loop CNC system directly affects the machine control accuracy, closed-loop CNC system in the excessive loss of stability will have an impact on the system. Based on the quality of the feed system and the spring mechanics model, the analytical expression of the influence of the transmission stiffness of the feed system and the torsional stiffness of the feed system on the amount of lost motion, and the principle and formula for the selection of relevant parameters are derived. Its purpose is to ensure that the machining accuracy of CNC machine tools in order to improve the speed, stability, reduce the steady-state and dynamic error