Research On Gear Modification Of Wheel Reducer For Large Mine Dump Truck

With development of the engineering machine,the gear transmission is depveloping toward the direction of high speed and heavy load,this puts forward higher requirements in the aspect of high reliability and transmission performance.Under the precondition of not changing the geometric size of gears and improving the production cost of gears,the gear modification technology is an important means of developing the heavy load,long life and high reliability gear transmission.This thesis research on the wheel reducer with 150 T mine dump truck is taken as the research object.By analyzing the transmission error of gear mesh and lead load distribution,according to the principle of gear modification,a kind of method for profile modification and lead modification is proposed.The major work is summarized as follows:1)This paper described the gear contact analysis theory and the previous study of the gear wheel gear deformation calculation formula.Taking into account the gear shaft elastic deformation and gear wheel deformation on the impact of gear deformation,the comprehensive deformation of the gear is obtained by using the Ishikawa formula.Then the gear meshing stiffness is obtained from the stiffness definition,which provides the theoretical basis for the calculation of the gearing parameters in the wheel unloader of the 154 T mine.2)The drive system model of the wheel reducer is established by using the mechanical drive system Romax Designer software.The theory of load contact analysis of gear gear surface is introduced,and the wheeled reducer model is simulated by Romax Designer software.The simulation results show that the existence of partial load in the transmission system is the same as the practical application.In order to solve this problem,it is necessary to modify the gears in the wheel reducer.3)The principle of gear profile modification and the determination scheme of gear profile modification parameters are introduced.In the MATLAB software,a small program for calculating the gear parameters is developed.The initial data of the gears are calculated by the simulation of the model.It is proved that the calculated initial gears are reasonable.The gears are modified by the different simulation curves.The modified curve of the gear reducer gear is determined by analyzing the simulation results.By comparing the results of the contact analysis,it is shown that the gear profile can reduce the transmission error caused by the gears during the meshing.The dynamic analysis software ADAMS is used to analyze the gears before and after the modification.The comparison results show that the smoothness of the gear transmission is improved by modifying the gears.4)The principle of lead modification and the method of determining lead modification parameter are introduced.Through analyzing the simulation results of the wheel reducer,the deformation of the shaft is obtained as the initial condition for the calculation of the lead modification parameters in the wheel reducer.By analyzing the distribution of lead length per unit length under different modification amount,the optimal lead modification modification parameters are obtained.The comparison of the gears in the front and rear wheel reducer shows that the lead modification can improve the load distribution of the gear surface.