| The ability of automobile transmission noise control in the vehicle performance evaluation plays a more and more important role. Gear meshing vibration and shock is the main source of transmission tapping noise. It is of great significance studying on transmission gear tapping vibration mechanism and nonlinear rules caused by varieties of internal and external incentive factors. A dynamic tapping model of transmission single gear under the influence of multi parameters is achieved in consideration of the effect of nonlinear internal and external factors in order to achieve these goals. The numerical response results and visual rattle states of the gear are calculated using the method of numerical analysis and software simulation get respectively. The analysis of various factors impact on the gear rattle is conduct based on the results. The specific procedure is as follows:(1) Researches of automobile transmission gear tapping dynamics modeling and rattle noise analysis, prediction and control are introduced. Deficiencies in modeling and simulation methods at present are analyzed. The research significance and content of this article are put forward then.(2) Analysis working principle of transmission and mechanism of vibration tapping of gears. In consideration of the effect of nonlinear internal and external factors which cause vibration tapping on the non-load gear of transmission system. Study on the mechanism of vibration and tapping in the gear meshing process caused by input speed, torque fluctuation, time-varying meshing stiffness, backlash, dynamic meshing error, meshing damping and other factors.(3) Aiming at the single stage gear, the dynamic modeling of the factors such as the input speed, the input torque fluctuation, the time-varying stiffness, the backlash of the gear, the meshing damping, the meshing error is developed. Based on the comparison and analysis of the four types of tapping determination, a method of tapping is proposed in this paper.(4) Numerical analysis on the transmission gear is conduct. The non dimensional treatment of the single stage gear pair tapping dynamics model is carried out. The numerical solution of the model is solved by the Runge-Kutta algorithm of MATLAB. The results show that the increasing of gear backlash, time-varying stiffness, gear error and the input torque and other factors amplitude will boost the percussion force, causing tapping state varies between unilateral and bilateral and changing periodic of the system. Increasing of the meshing damping can improve the tapping severe condition; input speed mainly determines the frequency of vibration system, is obvious to the influence of periodic system. The increase of meshing damping can improve the intensity of the impact. The vibration frequency of the system is mainly determined by input speed.(5) Transmission gear rattle simulation analysis was carried out in this paper. By means of AMEsim simulation software, a manual transmission model was established. Explore the rattle principle of the transmission gears, in the process of car speed from first gear to fifth gear under load state and non-load state respectively. Choose the first gear and second gear driving conditions, analysis non-load gear rattle condition respectively by the motivating factors as the research object. The results indicated that non-loaded gears are more likely to emerge rattle. Influence laws of all kinds of incentive factors for rattle of gear system are in consistent with those influence laws got from the analysis results of the single stage gear. |
PDF Full Text Request