ELASTODYNAMIC ANALYSIS OF MULTI-RING GEAR REDUCERS IN CONSIDERATION OF DEFORMATIONS OF GEAR-COUPLERS

The multi-ring gear reducer (MRGR) is a novel class of planetary gear transmission devices with small tooth number difference. It has numerous advantages over common gear reducers such as large transmission ratio, high loading capacity, compact volume, low fabricating cost and wide adaptability. To improve dynamic performance of the MRGR,the systematic elastodynamic equation is formulated by taking into account the elasticity of high-speed shafts, gear-couplers, meshing teeth and bearings. An ANSYS based finite element model is developed for the gear-couplers whose rigid-body motions are constrained by linear springs with equivalent stiffness. The stresses, displacements and elastic deformations of the gear-couplers are investigated in a whole motion cycle of the parallelogram mechanism. The actual loading states of the components are obtained by integrating iteratively the ANSYS based finite element analysis of the gear-couplers and the elastodynamic analysis of the MRGR. The simulation results reveal that both longitudinal and lateral deformations of the gear-couplers will greatly affect dynamic performance of the MRGR and the rating life of planetary bearings will be shortened as a result of elastic deformations of the gear-couplers.