Jixie chuandong (Jan 2023)
Analysis of Transient Elastohydrodynamic Lubrication of Asymmetric Polymer Planetary Gears
Abstract
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.
