Simulation Of AMT Shift Mechanism And Its Key Parts Optimization

Electric vehicle technology has developed rapidly in recent decades.Electronically controlled electric shift mechanism is critical to the performance and efficiency improvement of electric vehicles in high-performance electric vehicles and heavy-duty electric vehicles.However,the electronically-controlled electric shift mechanism causes transmission errors due to machining errors,assembly errors,deformation and wear of key components,and ambient temperature changes,which increase with service time and lead to shift misalignment and noise and shock problems.Therefore,the main contents of this thesis are as follows:(1)Wear and deformation of key parts of electronically controlled electric shift mechanismThe key parts of the shift mechanism selected in this thesis are the shiftgear mechanism and the shift rocker arm.The wear of the gearshift is obtained by using the analytical method to find the Hertzian stress and the relative sliding speed of the contact surface,and the tooth wear is obtained by combining with the Archard formula.The deformation of the gearshift is obtained by the time-varying meshing stiffness of the gearshift.The wear of the shift rocker arm is solved by the finite element method,and the deformation of the shift rocker arm is also solved by using the finite element method.(2)Research on transmission error of electronically controlled electric type shift mechanismEach influencing factor affecting the transmission error of the shift mechanism is analyzed,including the inherent error,assembly error,wear and deformation of key parts,etc..The influence value of each influencing factor on the transmission error is converted to the output by the transmission error formula to obtain the transmission error of the shift mechanism.The transmission errors solved in this thesis are static transmission errors and quasi-static transmission errors.(3)Experimental measurement and analysis of wear and transmission error of shift mechanismThe method of establishing the base point of wear measurement and the measurement method of wear are proposed for the wear measurement of the shift mechanism.For transmission error measurement of the shift mechanism,the rotation angle measurement is transformed to height measurement by the mechanism.The simulation data of wear and transmission error are compared with the test data,and the accuracy of the simulation model is verified.(4)Optimization of key parts of shift mechanism based on transmission errorBased on the transmission error simulation model,the key parts of the shift mechanism are structurally optimized.The response surface method is used for the deformation of the shift rocker arm,and its key geometric dimensions are selected as parameters for optimization.In view of the wear of the shift mechanism,the structural form of the shift rocker arm is optimized.This thesis mainly simulates the transmission error of the shift mechanism,the wear and deformation of the shift gear and the shift rocker arm.The test platform for the wear of the shift rocker arm was established and the transmission error of the shift mechanism was verified,and finally the deformation geometric parameters and wear structure of the shift rocker arm were optimized.The transmission error model obtained in this thesis and the optimization of key parts of the shift mechanism are of great significance to solve the problems of insufficient position caused by long-term gear shifting,and reduce the impact and noise caused by gear shifting.