Dynamic characteristics and load-sharing performance of concentric face gear split-torque transmission systems with time-varying mesh stiffness, flexible supports and deformable shafts

The concentric face gear split-torque transmission system is a new gear mechanism which integrates the advantages of face gears, split-torque transmissions and concentric transmissions. The power transmission through multiple branches improves the systematic load capacity. However, the uniformity of load sharing between branches seriously restricts the service life of the entire system. According to the Newton theorem, a lumped parameter model coupled with the vibrations of the gear with six degrees of freedom, the torsion of input shafts, the meshing of gear pairs, and the bearing supporting is established. Gear backlash, meshing damping, support stiffness, time-varying mesh stiffness, and modified transmission errors are considered in this dynamic model. The discrete solution of dynamic equations is obtained by using the numerical integral method of Runge-Kutta. Natural characteristics and the performance of dynamic load sharing are investigated. Furthermore, the effects of the factors including torsional stiffness, gear backlash and time-varying mesh stiffness on dynamic load sharing are explored. The results indicate that the above-mentioned factors greatly affect the performance of dynamic load sharing, and the phenomenon of tooth disengagement is observed.