考虑磨损误差的端齿盘分度精度的动态可靠性及灵敏度研究

Research on Dynamic Reliability and Sensitivity of Indexing Accuracy of End-toothed Discs with Wearing Error Factors

数控机床刀架系统中端齿盘分度精度的高低会直接影响整个刀架的分度精度。分析了端齿盘的多种加工误差和齿厚磨损误差,建立了多误差因素下端齿盘的分度误差模型,并计算出其可靠度。以端齿盘的分度误差模型为基础,结合可靠性灵敏度分析方法,建立了端齿盘分度精度的动态可靠性灵敏度的数学模型,给出了端齿盘各随机参数的灵敏度变化规律,分析了各随机参数的变化对端齿盘分度精度可靠性的影响程度。研究表明,端齿盘分度精度的可靠度随加载和卸载过程的累积作用而逐渐降低,各设计参数的敏感度在同一时间内变化趋势各不相同,对敏感参数加以控制可提高端齿盘分度精度的可靠度。

The levels of end-toothed disc indexing accuracy might have direct effects on the indexing accuracy of the tool rests.Tooth thickness wear errors and a variety of machining errors were analyzed.An indexing accuracy error model of the end-toothed discs with multiple error factors was established.On the basis of the indexing accuracy model of the end-toothed discs,a dynamic reliability sensitivity mathematical model was established by combining reliability sensitivity analysis method.The evolution rules of reliability sensitivity for each random parameters of the end-toothed discs were given.The influences of the random parameters on the reliability of the end-toothed disc indexing accuracy were analyzed.The results show that the reliability of the indexing accuracy of the end-toothed discs decreases gradually with the the loading and unloading processes.The variation tendency of the sensitivity of each design parameters at the same time is different.The sensitivity parameters should be controlled in order to improve the reliability of the indexing accuracy of the end-toothed discs.