非对称聚合物行星齿轮瞬态弹流润滑分析

Analysis of Transient Elastohydrodynamic Lubrication of Asymmetric Polymer Planetary Gears

为满足机械结构紧凑化、轻量化要求,在行星齿轮传动系统中可应用非对称聚合物齿轮。为研究非对称聚合物行星齿轮传动中内啮合轮齿的瞬态弹流润滑性能,建立非对称聚合物行星齿轮内啮合传动的润滑模型,采用多重网格法进行了数值求解与仿真分析;对比分析了行星齿轮内啮合与外啮合几何参数的异同,探讨了齿轮运行工况以及齿轮副材料对非对称聚合物行星齿轮瞬态弹流润滑的影响;考虑热效应的影响,探究了非对称聚合物行星齿轮内啮合最高温升与3个特殊瞬时啮合点的温度分布变化规律,对比分析了等温与热弹流润滑条件下不同齿轮材料的弹流润滑性能。结果表明,由于传动啮合方式的不同,行星齿轮内啮合的几何参数不同于外啮合,齿轮转速和载荷对弹流润滑效果影响显著;使用非对称聚合物齿轮可提高齿轮承载能力和改善齿轮的等温弹流润滑性能;但高温重载时聚合物齿轮材料影响轮齿强度和散热效果,非对称聚合物行星齿轮更适于在低温低速环境中应用。

Asymmetric polymer gears are used in planetary gear transmission system to cater for the design requirements of compact and lightweight mechanical structure. In order to study the transient elastohydrodynamic lubrication characteristics of the internal meshing teeth of the asymmetric polymer planetary gear transmission, a lubrication model of internal meshing gear transmission of asymmetric polymer planetary gear is established;numerical solution and simulation analysis is completed by the multi-grid method. The similarities and differences between the internal and external meshing geometric parameters of planetary gears are compared and analyzed. The influence of gear operating conditions and different materials of asymmetric polymer planetary gear on transient elastohydrodynamic lubrication is studied. Considering the influence of thermal effect, the temperature distribution of the highest temperature rise and three special instantaneous meshing points in the asymmetric polymer planetary gear was investigated. The lubrication properties of different gear materials under thermal and isothermal elastohydrodynamic lubrication are comparatively studied. The results show that due to the different transmission meshing methods, the geometric parameters of the internal meshing of planetary gears are different from those of external meshing gears. Speed and load have significant influence on the gear elastohydrodynamic lubrication performance. The bearing capacity and isothermal elastohydrodynamic lubrication performance of gears can be improved using asymmetric polymer gear. Polymer gear materials affect tooth strength and heat dissipation at high temperature and heavy load. Asymmetric polymer planetary gears are more suitable for low temperature and low speed environment.