Abstract:

The double curvature arc, elliptic arc and streamline arc were proposed as transition curves for roots of universal cross shaft in order to reduce stress concentration, by searching transition curves with low stress concentration factor. And the formulas of transition curves for roots of universal cross shaft were established. The examples for the formulas of transition curves were carried out and the FEM analyses for the samples were implemented. The FEM analysis results indicate that the stress concentration is relieved by the three transition curves put forward. 

Key words: shape optimization, double-curvature arc, streamline arc, elliptic arc, stress concentration, universal cross shaft

摘要：

提出变曲率过渡曲线理论，单纯从形状上寻求应力集中系数小的万向十字轴轴根过渡曲线。将双曲率圆弧曲线、椭圆曲线和流线形曲线作为万向十字轴轴根过渡曲线来降低应力集中从而提高万向十字轴的使用寿命；建立了三种过渡曲线的曲线方程，给出双曲率圆弧过渡曲线、椭圆弧过渡曲线及流线形曲线的设计实例，并进行了有限元分析。结果表明提出的三种曲线可以有效降低万向十字轴轴根的应力集中。

关键词: 形状优化, 双曲率曲线, 流线形曲线, 椭圆形曲线, 应力集中, 万向十字轴