谐波减速器组合曲线凸轮波发生器的设计与分析

Design and Analysis of Harmonic Reducer Combined Curve Cam Wave Generators

波发生器的形状直接影响柔轮的受力特性。柔轮是谐波减速器中最薄弱的部分,为提高其寿命,介绍了一种基于圆锥曲线组合的凸轮波发生器的设计。组合曲线凸轮波发生器轮廓由抛物线、连接圆弧和偏心圆弧组合而成;将抛物线与连接圆弧、连接圆弧与偏心圆弧平滑过渡作为约束条件,通过正交实验确定组合曲线凸轮波发生器各段曲线参数,分析了各参数对柔轮最大等效应力的影响程度;利用有限元软件,分别对标准椭圆凸轮和组合曲线式凸轮作用下的柔轮进行了瞬态动力学分析,并基于分析结果,利用nCode-Designlife软件,对柔轮的疲劳寿命进行了研究。结果表明,组合曲线凸轮波发生器作用下的柔轮最大等效应力比标准椭圆凸轮波发生器作用下的低;组合曲线凸轮波发生器作用下的柔轮啮合区的齿圈前后端应力明显降低,应力分布更加均匀,疲劳寿命也有所提高。

The shape of wave generator directly affects the mechanical characteristics of the flexspline.Flexspline is the weakest part of harmonic drivers.In order to improve its life,the design of a cam wave generator based on a conical curve combination is introduced.The combined curve cam is composed of a parabola,a connecting arc and an eccentric arc;the smooth transition between the parabola,the connecting arc and the eccentric arc is taken as the constraint conditions.The influence degree of each parameter on the maximum equivalent stress of the flexspline is calculated and analyzed by orthogonal experiment,and the curve parameters of each section of the combined curve cam wave generator are determined.The transient dynamic analysis of the flexspline under the action of standard elliptic cam and combined curve cam is carried out using the finite element software,and the fatigue life of the flexspline is studied using the transient dynamic analysis results based on the nCode-Designlife software.The results show that the maximum equivalent stress of the flexspline is lower than that of the standard ellipse cam wave generator,under the action of combined curve cam wave generator,the stress at the front and back ends of the tooth ring in the meshing area of the flexspline is obviously reduced,the stress distribution is more uniform,and the fatigue life is also improved.