Research on deformation and contact performance of planetary gear needle roller bearing assembly

ObjectiveTo meet the requirements of high power density and compactness, the planetary gear is designed as a thin-walled structure, which reduces the stiffness of the planetary gear and makes it easy to deform, thereby affecting the bearing capacity and service life of the bearing. In response to this problem, the deformation and contact performance of the planetary gear needle roller bearing assembly were analyzed and studied based on the principle of virtual work in elastic mechanics and the design method of rolling bearings.MethodsA mechanical analysis model of thin-walled planetary gear train with axial-rotation coupling was established by virtual work principle and rolling bearing design method, and verified by finite element simulation. The deflection curve of planetary ring, bearing load distribution, contact stress and other performance parameters were obtained by numerical calculation, and then the influence of driving torque and axial-rotation coupling on bearing capacity and life was analyzed.ResultsThe results show that the flexural deformation of the flexible planetary ring has obvious influence on the load distribution of the bearing, and the coupling effect of planetary ring and needle roller should be considered in the calculation of the performance of the actual planetary gear train needle roller bearing. The best way to consider the convex shape of the needle roller is logarithmic. Bearing load and contact stress increase with the increase of revolution speed and driving torque, and the position angle 55°-305° is the bearing area of needle roller. Bearing fatigue life decreases with the increase of revolution speed and driving torque.