Research And Verification On Load Sharing Characteristics Of Planetary Gear Train With Flexible Gear Ring

Planetary gear train has the characteristics of small size,coaxial deceleration and wide transmission range.However,the installation and manufacturing error of each component in planetary gear train will make the load of each planetary gear train distributed unevenly,which will affect the load sharing performance of planetary gear train.Therefore,it is necessary to study the load sharing performance of planetary gear train.In this paper,the load-sharing performance of planetary gear train with thin-wall sleeve is studied from three aspects:theoretical calculation,finite element simulation and load-sharing experiment.The details are as follows:（1）The internal meshing stiffness of planetary gear train with thin-wall sleeve is solved by theoretical calculation and ANSYS finite element simulation.Firstly,according to the definition of Ishikawa formula,the normal force of planetary gear is calculated.Then,based on the material mechanics theory and Timoshenko beam theory,the tooth deformation,contact deformation,inner ring matrix and sleeve deformation on the inner ring are solved,and the time-varying internal meshing stiffness is solved by substituting the formula.Then,a three-dimensional model of planetary gear train with flexible gear ring is established by ANSYS.Through statics analysis,the deformation of planetary gear and inner gear ring on the meshing line direction is extracted,and the time-varying internal meshing stiffness is obtained.The theoretical calculation and ANSYS simulation results show that the error between the two is small,which proves the accuracy of the theoretical calculation and lays a foundation for solving the load sharing coefficient.（2）According to the centralized quality method,the translation-torsional coupling model of planetary gear train with thin-wall sleeve is established.On this basis,factors such as meshing stiffness,meshing damping,component error,component floating,support stiffness and torsional stiffness are considered.Then,different components of the whole system in x,y and torsion direction are analyzed,and then the system dynamics equation is deduced,which is arranged into matrix form.The meshing force on each meshing branch is solved.According to the definition of the load sharing coefficient,the load sharing coefficient of the system is obtained.（3）The control variable method is adopted to study the influence of system parameters and structural parameters on the load coefficient of planetary gear train by changing the parameters one by one on the premise of keeping other irrelevant parameters unchanged.Firstly,the influence of system parameters,including input power,input speed,planetary carrier floating,sun gear floating,gear pressure Angle,sleeve thickness,etc.on load sharing performance is investigated.Then,the sensitivity of the installation and manufacturing errors of the solar gear,planetary gear,planetary carrier and inner ring gear to the load sharing coefficient is studied,and the sensitivity ranking of the installation and manufacturing errors of each component to the load sharing performance of the system is finally obtained.（4）The load equalization test of the planetary gear train with five planetary gears is carried out.The stress analysis of the planetary gear train is carried out by ANSYS,and the best patch position was obtained.The internal load coefficient is calculated through the signal amplitude of each meshing branch in different meshing period.Then the load sharing performance test is carried out on the self-developed planetary gear test bench,and the data under different working conditions are processed.The original data and the filtered data graph are given,and the load sharing coefficients under two working conditions are calculated.By comparing the theoretical calculation results with the experimental results,the accuracy of load sharing coefficient calculation is verified.