Influence Of Eddy-current Retarder On Urban Bus Main Reducer

The use of eddy current retarders in commercial vehicle has been relatively common,especially for urban buses due to frequent start,acceleration,braking,the installation and using of eddy current retarder has obviously enhanced the brake effect.Compared to the vehicle without the eddy current retarders,the most obvious effect is that it can reduce the brake shoe and brake wheel wear,so do the bus operating cost,and the brake noise.meanwhile it brings a good solution to the thermal attenuation phenomenon of brake which caused by the long vehicle braking.It can cut down the tire puncture,stratification and other dangerous problems.besides it can improve the safety performance of vehicle driving.However,according to the vehicle maintenance statistics of the cars installed with eddy current retarders in recent years show that: the use of eddy current retarder has a certain impact on the vehicle's main reducer,especially for those cars that had installed with eddy current retarders after their been mannfactured,the main reducer hypoid gear failure significantly increases,the service life has also been reduced.This paper points out the problem after the analysis of a large number of maintenance statistics,and introduces the structure,working process,braking principle,control mode and installation method of the eddy current retarder commonly used in urban bus.Taking the most common urbar cars--for example,from the installation position of the retarder,the macroscopic force analysis of the main gear reducer is analyzed.Especially after the installation of retarder,the macro force of the main reducer changes.The bending strength and the contact stress intensity of the main and driven gear teeth of the main reducer are re-examined,and the reason of the reduction of the gear life of the main reducer is analyzed macroscopically.The three-dimensional software UG of the main gear reducer with the most widely used model of the bus is selected,and the gear model is established by using the Ansys Workbench Environment finite element analysis software.The flexural strength and the contact stress intensity of the gears calculated in the second chapter are compared with the simulation values of the finite element software to verify the boundary conditions of the finite element software and the correctness of the simulation results.Through the simulation of the contact stress map,perspective,etc.It can be seen that in the main anddriven wheel tooth surface contact area of the maximum equivalent stress,the most prone to fatigue damage parts.In this paper,the cyclic pulsating load spectrum on the hypoid gear is reconstructed by using the load spectrum module in the Workbench finite element software,and the main part is used to analyze the fatigue.In this paper,the modal analysis of the main reducer gear is carried out by using the simulation software.The frequency of the first 6 orders of the hyperboloid gear is calculated,and the vibration modes are listed.The corresponding measures are put forward for the simulation results.,To avoid the occurrence of gear resonance.Finally,according to the simulation results,the selection of the material of the main reducer gear of the retarder vehicle and the improvement of the basic parameters are put forward..This paper draws some useful conclusions through theoretical calculation and simulation analysis,which has certain practical,theoretical reference value and good prospect of engineering application.