对称与非对称齿轮齿根弯曲应力对比分析

非对称渐开线直齿圆柱齿轮作为一种新型的齿轮.无法通过现有的解析法对其齿根弯曲应力强度进行计算.通过分析其轮齿齿廓结构特点,以平截面法为基础,建立了一种新的求解方法,推导出该类齿轮齿根弯曲应力解析法计算公式.以相同模数及齿数的对称、非对称齿轮为研究对象,在相同工作状况下,分别通过解析法和有限元法,对对称、非对称渐开线直齿圆柱齿轮正向、反向旋转过程中轮齿齿根的弯曲强度进行了研究.取啮合齿轮对一个啮合周期内的五个特殊位置点,对两种齿轮轮齿两侧齿根弯曲应力进行了对比分析.最后通过阶梯增载疲劳试验法,对两类齿轮进行了轮齿齿根的弯曲疲劳强度试验,通过试验数据对理论分析结果进行了验证. 

Comparative analysis of root bending stress between spur gears with symmetric and asymmetric involutes

The spur gear with an asymmetric involute is a new kind of gear. Its bending stress could not be calculated by existing analytical methods. Through analyzing the tooth profile characteristics, a solving method of bending stress for the gear was proposed on the basis of the plane cross-section method, and an analytical formula was derived to calculate the root bending stress of tile gear. Spur gears with symmetric and asymmetric involutes, with the same module and teeth numbers, were as the research objects. In the same working conditions, the bending strengths of the two gears were studied by the analytical method and finite element method during forward and reverse rotation. Five special positions were selected during the meshing period and their bending stresses on both sides were analyzed comparatively. Finally, by the ladder loading fatigue test method, the two gears were tested in tooth root bending fatigue strength experiment. The experimental data verified the theoretical analysis result.