Dynamic Performance Analysis And Optimization Of Increasing Helical Planetary Gear Trains

Increasing planetary gear trains are widely used in industry and life, at the same time, the contact ratio of helical gear is bigger than spur gear which can make the gear train runs more steadily. Therefore, research on the dynamic characteristics of the increasing helical planetary gear train is meaningful in terms of the reliability, vibration and noise. Optimization on increasing planetary gear train can make it more compact.Based on one-stage increasing helical planetary train, this paper mainly concentrates on dynamic characteristics and parameter optimization, the main works of this paper are summarized as follows:First, the lumped parameter model of one-stage increasing helical planetary train is created. The model is built in full consideration of the meshing stiffness, the mesh error, backlash and the system damping. The connections between components, component and foundation are assumed to be spring-damper model, so as to the connections between gear teeth.Second, the analysis model is created. The second-order dynamic differential equations of planetary gear, sun gear, ring gear and planetary carrier are established based on Newton’s second law. Then, equations are rewritten in matrix form in order to obtain its stiffness matrix and mass matrix.Third, the natural frequency and principal modes are acquired. The natural frequency and principal modes are achieved according to inherent characteristic computation theory by using MATLAB. Furthermore, how the parameters such as the support stiffness, mass, rotational inertia and meshing stiffness have an influence on the natural frequency of the system is studied.Finally, the design parameters of the system are optimized in order to reduce the volume of the increasing helical planetary gear train.