恒定加工条件及定期补偿下的刀具渐变可靠性灵敏度分析方法  

Gradual Reliability and Its Sensitivity Analysis Approach of Cutting Tool in Invariant Machining Condition and Periodical Compensation

作　　者：李常有[1] 张义民[1] 王跃武[2] 

机构地区：[1]东北大学机械工程与自动化学院,沈阳110819 [2]沈阳机床(集团)有限责任公司设计研究院,沈阳110041

出　　处：《机械工程学报》2012年第12期162-168,共7页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51005041);国家科技重大专项(2010ZX04014-014);中央高校基本科研业务费专项资金(N090303005);中国博士后基金(20100481199)资助项目

摘　　要：据统计,由刀具失效导致的停机时间超过机床被迫停机时间的1/3,故开展刀具渐变可靠性及其灵敏度分析的研究对提高机床的运行可靠性具有重要意义。采用连续时间、连续状态、具有非减独立增量的非平稳Gamma过程描述刀具磨损量的变化过程。根据加工偏差不大于机床给定加工精度的原则,构建刀具制造及磨损量检测有无误差两种情形下、恒定加工条件及定期补偿的刀具渐变状态函数,由此推导出相应的渐变可靠度模型。在此基础上给出渐变可靠度模型对各个参数的灵敏度计算方程。通过数值实例分析,阐述了通过提出的渐变可靠性模型及灵敏度分析方法提高刀具运行可靠性的应用过程。这一工作为提高恒定加工条件及定期补偿下刀具的运行可靠性提供切实可行的理论和方法基础。It has been reported that the downtime due to cutting tool failure is more than one third of the total forced downtime of the machine tool. Therefore, it is very knportant for improving the machine tool operation reliabitity to investigate the gradual reliability and its sensitivity of the cutting tool. A non-stationary Gamma process which is a continuous-time, continuous-state and monotone increasing stochastic process with independent increment is employed to describe the wear process of the cutting tool. The gradual state function of the cutting tool with the periodical compensation for wear and the invariant machining condition are formulated according to the principle that the machining error is not more than the given machine tool machining accuracy in two cases. One has the assumption that the cutting tool has not the machining error and the detection of the wear of the cutting tool is accurate. The other is the contrary one. Then, the corresponding gradual reliability is derived. On this basis, the sensitivity of the gradual reliability is analyzed. It is described by the numerical examples how to improve the operation reliability of the cutting tool using the proposed gradual reliability model and its sensitivity analysis results. The more feasible theory and method for improving the cutting tool operation reliability with the periodical compensation for wear and the invadant machining condition than the existed works might be provided by this work.

关 键 词：刀具 渐变可靠性 灵敏度分析 Gamma过程 

分 类 号：TH161[机械工程—机械制造及自动化]