Study On Dynamic Characteristics Of High Speed And Heavy Load Planetary Gear Transmission System Based On Bearing Pre-tightening Force

The project comes from the project of National Natural Science Foundation of China "Research on load sharing mechanism and configuration of super-high power multi-planetary wheel flexible pin-shaft wind power gearbox"(51405048).Planetary gear transmission system has many characteristics,such as high power density,strong load-carrying capacity,compact structure,power diversion,small mass and so on.It is used in high-speed and heavy-load transmission system.At the same time,bearing is an important basic part of all kinds of mechanical transmission components,and it is also widely used in planetary gear transmission system.Therefore,the study of the influence of bearing preload on the dynamic characteristics of high-speed and heavy-load planetary gear transmission system has important theoretical value for improving the dynamic characteristics of high-speed and heavy-load planetary gear transmission system.In this paper,the high-speed and heavy-load planetary gear transmission system is studied.Aiming at the influence of pre-tightening factors on the system,the meshing stiffness analysis,support stiffness analysis,transmission error analysis and load-sharing performance analysis of each pair of planetary pin-supported bearings are carried out.The influence law of bearing preload on the dynamic response of high-speed and heavy-load planetary gear transmission system is obtained.The finite element model of high-speed and heavy-load planetary gear transmission system considering thermal deformation is established.The contact temperature and meshing performance of the system's tooth surface are analyzed.The influence law of thermal deformation on the dynamic response of high-speed and heavy-load planetary gear transmission system is obtained.The main contents of this paper are as follows:1.The basic structure and transmission principle of high-speed and heavy-load planetary gear transmission system are analyzed.The dynamic analysis model of high-speed and heavy-load planetary gear transmission system considering bearing preloading and the dynamic analysis model of rolling bearing are established.2.The dynamic parameters of high-speed and heavy-duty planetary gears under bearing preloading are identified,and the influence of bearing preloading on meshing stiffness of the system is analyzed;the contact load and elastic deformation of the bearing are analyzed by using the dynamic equation of planetary pin bearing and the calculation formula of bearing elastic deformation,and the influence of bearing preloading on bearing support stiffness is studied;the influence of bearing preloading on planetary gears is analyzed.The influence of dynamic transmission error of transmission system and the influence of bearing preload on load sharing of planetary gear transmission system are analyzed.3.The natural frequencies and vibration modes of the system are obtained by using the dynamic model of the high-speed and heavy-load planetary gear transmission system;the influence of bearing preload on the dynamic acceleration response and meshing force of each component of the planetary gear transmission system is studied;and the influence of bearing preload on the dynamic acceleration response of the planetary pin bearing is analyzed.4.Based on the temperature field,the finite element model of the high-speed and heavy-load planetary gear transmission system under bearing preloading is established;the influence of bearing preloading on the contact temperature,flash point temperature and contact load of the planetary gear transmission system is obtained;the influence of bearing preloading on the dynamic acceleration response of the system components under the temperature field is analyzed;and the dynamic meshing force of the system components under the temperature field is studied.The influence of tightness on the dynamic acceleration response of planetary pin bearings.