齿啮式谐波传动中短环型柔轮变形及应力

Study on deformation and stress of short ring-flexspline in engagement output harmonic drive

柔轮的疲劳断裂破坏是影响其使用寿命的主要原因,对柔轮的变形和应力分布规律进行研究,是谐波齿轮研究的重点。齿啮式谐波传动中短环型柔轮具有独特的结构特点,可有效解决杯型和钟型柔轮加工困难以及在筒底转角处应力集中的问题,从而延长谐波传动的使用寿命。文章利用弹性力学和材料力学理论,建立了短环型柔轮的数学模型,并对其变形和应力进行理论分析;在考虑几何非线性基础上,利用有限元方法,建立了谐波齿轮的接触非线性有限元实体模型,对其进行有限元仿真分析,并与理论分析结果进行比较,得到了短环型柔轮的初始变形和应力分布规律,为研究齿啮式谐波传动问题提供了理论依据。

The fatigue rupture of flexspline is the dominating reason that affects the working lifetime of harmonic drive, so the study on deformation and stress distribution of flexspline is a key in the research of harmonic gear drive. As short ring-flexspline in engagement output harmonic drive has its own unique structural characteristics, it can avoid the difficulty in manufacturing and the problems of stress concentration at the corner of cylinder bottom for cup-flexspline and bell-flexspline, and it＇s able to extend service life of harmonic drive. At present the domestic status lacks of systematically theoretical study on deformation and stress of short ring-flexspline in engagement output harmonic drive. By using elastic mechanics theory and material mechanics theory, the mathematical models of short ring-flexspline were built, and its deformation and stress were analyzed in theory. Considering geo- metrical nonlinearity and contact nonlinearity, the nonlinear finite element model of harmonic gear was established by FEM, and the simulation analysis was carried out. The simulation results revealed the initial deformation and stress distribution of short ring- flexspline, and the comparison between the numerical and theoretical results proved that the simulation results were reliable. This study provided some valuable conclusions for the coming investigation on the engagement output harmonic drive.