| This thesis combines the National Natural Science Foundation of China project"Variation theory and key design technology of silent chain(51775222)" and the key research and development project of Science and Technology Development Plan of Jilin Province "Research on Key Technology of Engine Timing Chain System for Passenger Vehicle Hybrid Power(20200401136GX)”,the layout design of the parallel-shaft dual-clutch automatic transmission chain transmission system is carried out,and the key parameters of the chain plates and sprocket of the internal-external compound meshing Hy-Vo silent chain system are designed.The dynamic characteristics of chain drive system at different speeds are analyzed and the vibration characteristics of the chain transmission system are analyzed by the finite element method.Finally,the acoustic radiation analysis of the silent chain system is carried out.The research results of this paper can be used for reference to improve the vibration and noise characteristics of parallel shaft dual clutch transmission chain transmission system.Based on the research status and development trend of dual clutch transmission and silent chain transmission technology,according to the output parameters of a 4GB engine and the meshing principle of tooth chain,the design and calculation of Hy-Vo silent chain plate,pin shaft and sprockets with internal and external compound meshing of long waist reference hole in the silent chain system of dual clutch automatic transmission are carried out,and the layout of the system is designed.The overall layout of the system is designed and the system model is established by using the calculated chain plate,sprocket and other related parameters.In the multi-body dynamics software Recur Dyn,the system dynamics characteristics of the chain drive system under the conditions of low engine speed,peak torque and peak power are studied.The transmission error,the movement track of chain plate and the contact force between chain plate and sprocket are analyzed.It is found that the dynamic performance of the silent chain system of the dual clutch transmission designed in this paper is better at the speed of 3800 rpm corresponding to the peak torque of the engine,and the meshing contact force between the chain plate and each sprocket under this working state is extracted,which provides practical and reliable excitation parameters for the next step of vibration characteristic analysis of the system.Based on the modal analysis theory of chain transmission system,the finite element model of rolling pin silent chain system is established,and the static analysis is carried out to verify the strength and stiffness performance of the system;the modal analysis with prestress is carried out to solve the natural frequency and vibration mode of the system in the low-order mode,so as to evaluate the dynamic characteristics of the system structure and realize the diagnosis and early warning of serious vibration fault.Based on the vibration response analysis theory,the meshing contact force extracted from the multi-body dynamics analysis in time domain is converted into the amplitude and phase parameters in frequency domain,which are used as the excitation load in the frequency response motion equation to analyze the dangerous resonance frequency.Finally,based on the acoustic software LMS Virtual.lab Acousics,the acoustic model of the system is established,and the distribution of the sound pressure of the silent chain system of the dual clutch transmission is solved under different frequencies.The research results of the acoustic characteristics further verify the rationality of the system design,and will provide reference for its further structural optimization design.The research results of this paper provide a certain reference value for realizing the independent design of dual clutch automatic transmission and improving the NVH performance of domestic vehicles. |
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