谐波柔轮力学分析与疲劳寿命研究
2018-03-21叶南海邓鑫何韵孙昱晗
叶南海 邓鑫 何韵 孙昱晗
摘 要:为了完善谐波齿轮刚柔轮系统装配与啮合过程中的力学响应及柔轮疲劳寿命研究,提出了一种基于刚柔耦合与瞬态动力学分析理论的刚柔轮系统装配与啮合分析方法,得到了更加准确与合理的谐波柔轮装配及啮合过程中柔轮的应力分布和疲劳失效位置;柔轮结构和材料参数变化对其疲劳寿命的灵敏度研究,指出了柔轮疲劳设计的关键参数,并进一步指出了柔轮的疲劳寿命尺寸效应具有敏感区间,据此建立了柔轮的疲劳寿命模型.结果表明,谐波齿轮刚柔轮系统的力学与疲劳寿命分析不能忽略装配与啮合过程的影响;柔轮的设计应该规避疲劳寿命尺寸效应的敏感区间,以提高谐波齿轮的使用寿命.
关键词:谐波齿轮; 瞬态动力学; 刚柔耦合; 灵敏度分析; 疲劳寿命
中图分类号:TH132.43文献标志码:A
Abstract:In order to improve the mechanical response and fatigue life of the flexible spline (FS) during the assembly and meshing of the rigidflexible wheel gear of the harmonic drive, an assembly and meshing analysis method of rigidflexible gear system based on rigidflexible coupling and transient dynamic analysis theory was proposed. Stress distribution and fatigue failure position of FS were obtained more accurately and reasonably. The sensitivity of the structure parameters of FS and material property to its fatigue life indicates that the key parameters of the fatigue design of FS, and the fatigue life size effect of FS which has sensitive range, are also noted. In addition, the fatigue life model of FS was established. The results show that the mechanical and fatigue life analysis of the rigidflexible gear system of the harmonic drive cannot ignore the influence of the assembly and meshing process. The design of flexible wheel should avoid the sensitive range of fatigue life size effect to improve the service life of harmonic drive.
Key words:harmonic drive;transient dynamic;rigidflexible coupling;sensitivity analysis;fatigue life
諧波齿轮是在薄壳弹性变形理论基础上发展起来的一种传动装置,其结构主要包含刚轮(CS)、柔轮(FS)和波发生器(WG)三个部件(以下简称刚柔轮系统).相比传统减速器,谐波齿轮具有体积小,传动比大,承载高,传动效率高等诸多优点,因而被广泛用于航天航空、军工装备、医疗器械、工业机器人等高新技术领域.目前,约90%的谐波齿轮应用在机器人工业和精密定位系统中,已成为现代工业重要的基础部件.
近年来,有限元分析方法被广泛用于谐波齿轮的研究[1-2],Len等人[3]通过有限元的方法研究了齿形几何结……
