| The face gear drive has the advantages of high load carrying capacity,low vibration and noise,and is conducive to lightweight design,which makes the face gear drive a great advantage in the aerospace field.When the cylindrical gear and the face gear mesh,the common normal line coincides and the meshing force direction is stable,so it has good power split-converging characteristics.The planetary transmission system has the advantages of large transmission ratio,strong bearing capacity,high efficiency,stable operation,etc,and is widely used in the industrial field.Ideally,the load of each cylindrical gear and each planetary gear in the gear transmission is evenly distributed,but the actual load of each gear is different due to errors and other factors in the transmission process.Gears with larger loads are prone to wear and failure,thereby shortening the life of the entire transmission system.Therefore,how to ensure the evenness of the load distribution of the transmission system,that is,the uniform load characteristic,is of great significance to the engineering application of the transmission system.In this subject,taking the face gear-planetary gear transmission series system as the research object,the time-varying meshing stiffness calculation,static load sharing characteristics research,dynamic load sharing characteristics research and inherent characteristics research were mainly carried out.The main research work of the thesis is as follows:(1)Using the calculation method of ISO6336 to calculate the stiffness of the planetary gear transmission system,the calculation basis for the meshing stiffness of the face gear transmission system and the finite element stiffness calculation method were given,and the time-varying meshing stiffness of the face gear transmission system was calculated.This lays the foundation for the study of the load sharing characteristics of the face gear-planetary gear transmission series system.(2)Considering the shaft support deformation,torsion deformation and meshing deformation between gear pairs,the static load distribution characteristic calculation model of the transmission system was established,the static balance equation of the transmission system was deduced,and the static balance equation of the transmission system was calculated.The effects of eccentricity error,support stiffness,meshing stiffness,pressure angle and power on the static load sharing characteristics were studied.(3)Taking into account the acceleration and damping of the components,the time-varying meshing stiffness was adopted,and the stiffness excitation due to the change of the number of meshing teeth during the meshing process of the gear pair was incorporated into the model.The dynamic model of the face gear-planetary gear transmission series system was created,the dynamic balance equation of the transmission system was deduced,and the dynamic load sharing characteristics were studied.(4)In this paper,the necessary simplification of the dynamic equation of the face gear planetary gear transmission series system was carried out.By solving its eigenvalues,the natural frequency and mode vector of the transmission system were obtained.The vibration modes of the transmission system were divided into four categories,and the modal strain energy and modal kinetic energy of the transmission system were studied.The effects of meshing stiffness,support stiffness and component quality on natural frequencies were studied,which provided a theoretical basis for avoiding the resonance zone of the transmission system by optimizing system parameters. |
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