CHARACTERISTIC STUDY OF TRANSMISSION GEARS AND THEIR STRUCTURAL OPTIMISATION FOR MULTIPLE-UNIT TRAINS BASED ON FINITE ELEMENT ANALYSIS

This paper introduces the basic structure of the gear transmission system in multiple-unit trains and established the corresponding kinetic equation model. Subsequently, the corresponding finite element model was constructed using the kinetic equations of the system. After verifying its validity, the paper tested the intrinsic frequency, critical axle speed, and transmission error of the transmission system under varying mesh stiffness. The first- order intrinsic frequency and axle critical speed showed significant increases when the mesh stiffness exceeded 104 N/m, but they remained essentially unchanged after reaching 109 N/m. The transmission error decreased as the mesh stiffness increased. In conclusion, the design of the gearing system in multiple-unit trains should focus on achieving a sufficiently large gear meshing stiffness. However, considering the cost of improving the meshing stiffness, an excessively high meshing stiffness may not necessarily yield better results. Based on the findings, this paper suggests that a meshing stiffness of 109 N/m exhibits the most favourable effect.