Influence Of Interference Amount On The Static And Dynamic Performance Of An Unitized Carrier-type Axle Housing

The drive axle of the automobile is located at the end of the power transmission system,the force on it is complicated and it is one of the important sources of vibration noise.The drive axle housing is an integral part of the drive axle.On the one hand,it guarantees the stability of the working environment inside the housing.On the other hand,it bears the weight of the body and bears the counterforce and counter-torque from the gears,the axle and the wheels.The working conditions of it are awful,which are very vulnerable to failure,its dynamic characteristics also directly affect the NVH performance of the vehicle because it is connected to the car body.Therefore,the static and dynamic performance should be both considered in the study of the drive axle housing.Many scholars native and abroad have been on the study of the drive axle housing,the object of these studies are whole casting drive axle housing mostly,and the purpose of them focused on the static strength and fatigue life,but the study for other types of drive axle housing and dynamic performance is less.The object of this study is a unitized drive axle housing,which is assembled by the interference fit.The biggest difference between it and the whole casting drive axle housing is that the interference will directly affect the performance of the drive axle housing,and there is less research on it.In this thesis,the amount of interference of the unitized drive axle housing is taken as the research object,the influence of interference to the static and dynamic performance of drive axle housing is comprehensively analyzed using the theoretical calculation,simulation and testing.Firstly,the load of each part inside the housing is obtained according to the local force analysis and calculation,and then the overall force of the housing is obtained by equivalent and simplified,and the maximum stress value of it is calculated and checked by four typical working conditions.Secondly,the calculating formula of the combined stress is derived according to the theoretical model of elastic mechanics,and then the strength of housing with the maximum interference value is calculated and checked.In the static simulation,the effect of the interference value on the stress and deformation of the housing is studied in pure interference fit condition and four typical working conditions.The simulation results are compared with the theoretical calculation results,and the influence of the interference on the static performance of the housing is analyzed.Furthermore,the inherent frequency and vibration model of the housing is get under working state and free state modal analysis,the results can be used to avoid the occurrence of resonance and as a preparation for the flexible body in the dynamical model.In the dynamic simulation,the vibration acceleration of housing under different interference value is measured.Then,the test of the drive axle assembly was carried out,and the vibration acceleration was obtained.The simulation results are compared with the experimental results,and the influence of the interference value on the dynamic performance of the housing is obtained.Finally,the interference interval that can make both the static and dynamic performance better is summarized out according to the above research results.