基于有限元法的变齿厚内齿轮包络外转子鼓形蜗杆热力学分析

Thermal Stress Analysis of External Rotor Drum Worm With Variable Tooth Internal Gear Enveloping Based on Finiteelement Method

变齿厚内齿轮鼓形蜗杆传动是一种新型蜗杆传动,它由变齿厚内齿轮和利用包络形成的鼓形蜗杆两部分组成。它具有体积小、重量轻、结构紧凑以及大传动比等特点,在机器人智能关节领域有着广阔的应用前景。蜗杆传动在工作时会产生大量的热,同时电机置于蜗杆内部也会产生大量的热,使蜗轮蜗杆发生变形,产生热应力。为了掌握内齿轮包络鼓形蜗杆传动副的热应力分布及其热变形情况,探讨温度对最大应力的影响,做了以下研究。首先,利用微分几何与啮合理论通过Creo建立齿面数学模型;其次,将模型导入Ansys Workbench中对其进行热分析和热力学分析;最后,利用参数化设计的方法,分析出在特定结构载荷的作用下,温度对蜗轮蜗杆的最大等效应力的影响,并得出最大应力与温度变化的关系曲线。

Drum-type worm gear enveloped by internal variable-tooth-thickness gear is a new-type worm drive, composed of internal variable-tooth-thickness gear and drum-type worm gear formed by its envelope,which characterizes small size,light weight and high transmission ratio.It has a widespread application prospect in robot intelligent joint field.Worm drives generate a lot of heat during operation and motors placed inside the worm also generate a lot of heat.This generated heat causes deformation of the worm gear and generates thermal stress.In order to grasp the distribution of thermal stress and the thermal deformation of the drum-enveloped worm gearing with inner teeth enveloping and explore the influence of temperature on the maximum stress,we have done the following studies. First,establish a mathematical model of the tooth surface through the aid of differential geometry and meshing theory. Next,import the model into ansys workbench for thermal analysis and thermodynamic analysis.Finally,using the method of parametric design,analysis how temperature effect the maximum stress of worm gear under the influence of specific structural load and obtain the curve of maximum stress with temperature changes.