Vibration Analysis Of Mechanical Transmission System Of A Car

With the development of the automotive industry,people are increasingly demanding the comfort of automobiles.One of the most important aspects affecting comfort is the control of car’s vibration and noise.As an important part of the automobile transmission system,the vibration performance of the transmission directly affects the overall NVH performance of the automobile.Therefore,the analysis of the vibration and dynamic performance of the transmission system has an important practical significance to improve the vibration performance of the transmission.This paper focuses on the transmission system of transmission,the main research contents are as follows:For the manual mechanical transmission of a 2015 Santana car,the reasons for the external excitations such as the disturbance torque generated by the inertial force of the crankshaft linkage mechanism of the transmission system,the disturbance torque generated by the cylinder pressure,and the output shaft load were analyzed.Stimuli and excitation characteristics of the transmission drive system gear stiffness,gear error and gear pair meshing impact and other internal incentives and incentives.According to the transmission form and characteristics of transmission system,the mathematical model of gear meshing vibration of transmission system is established.According to the transmission system parameters and a multi-body system dynamics software,a three-dimensional model of a two-shaft five-speed transmission system.is established.By adding drive,constraint and load to the model,the dynamics model of the transmission system is established.The change of gear meshing contact force and speed transfer error,the vibration characteristics of meshing gear and input and output axis and the influence of transmission system on the vibration of transmission box are studied under the first,three and five gear positions.The influence of the different gear positions on the transmission error of the bearing meshing gear and speed is compared and analyzed,and the vibration characteristics of the meshing gear,the input and output axis and the box in different gear positions are also compared and analyzed.By changing the input shaft speed and output shaft load,the influence of speed and load variation on gear contact force and speed transfer error is studied.According to modal analysis theory,ANSYS analysis software was used to mesh,analyze and modally analyze the first,third,and fifth gear meshes of transmission system,and the first twenty intrinsic modal frequencies and corresponding mode shapes of meshing gears were obtained.,and conducted analysis of modal frequencies and mode shapes.The resonance frequency range and corresponding speed of the three gears of the transmission system are determined,and the method of avoiding resonance is analyzed.