Design And Analysis Of Chain Drive Power Coupling For Hybrid Vehicles

This article was jointly supported by the National Natural Science Foundation of China project "Mutation Mechanism and Key Design Technology of Toothed Chain(51775222)" and the Key Research and Development Project of Science and Technology Development Plan of Jilin Province "Key Technology Research on Timing Chain System for Hybrid Vehicle Engines(20200401136GX)".The arrangement of engines and motors in hybrid vehicles takes on various forms,and the coupling method between these power sources is currently a focal point of research.This article specifically focuses on the design and analysis of a chain-driven power coupling mechanism,with the following research objectives:First,based on the current status of hybrid vehicle power couplers,this paper designs a chain-driven power coupling mechanism by comparing and analyzing the characteristics and power distribution methods of different types of hybrid vehicles.It presents the coupling method and operating modes achievable by this power coupling mechanism under various operating conditions.By considering overall vehicle performance parameters and requirements,parameter matching calculations are performed,and a power coupling device compatible with the engine and electric motor is designed by selecting suitable engine,electric motor,and battery types.Second,the parameters of the planetary gear mechanism are designed and validated for strength,including checks on tooth contact strength and tooth root bending strength.The primary geometric parameters of the planetary gear mechanism are determined,and a parameterized model is created.Furthermore,the parameters of the toothed chain drive system,such as chain plate parameters,sprocket parameters,and toothed chain system parameters,are designed.Finally,the design parameters for the chain-driven power coupler are obtained,and a three-dimensional model is established.Thirdly,in order to explore the vibration characteristics of the chain drive power coupler system under high-speed working conditions,a finite element analysis model of the system is established,and static analysis and modal analysis are carried out.The static analysis results show that the maximum stress of the planetary gear mechanism is less than its failure stress,and the deformation is very small and can be ignored.Modal analysis obtains the first six modal shapes and natural frequencies of the planetary gear mechanism.The results show that the first natural frequency is higher than the vibration frequency brought by the external environment,so resonance will not occur.Similarly,static analysis and modal analysis are carried out on the master and slave chain wheels and the chain drive system.The results show that the chain drive system can meet the design requirements for strength and stiffness.Fourthly,a multibody dynamic analysis of the toothed chain drive system of the chain drive power coupler is carried out to study the dynamic characteristics of the system at three speeds of 2000 r/min,3000 r/min,and 4000 r/min.The instantaneous transmission ratio,meshing impact between the chain plate and the master and slave chain wheels during mutual engagement,and chain plate angular velocity are calculated.The results show that the entire operating cycle is relatively stable and meets the design requirements of the chain drive.In summary,the design and analysis method of the single-planetary-row chain drive power coupler proposed in this paper has certain validity and feasibility,and has a certain theoretical reference value for the research of hybrid vehicle power couplers.