Dynamic Analysis Of Six Connecting Rod Transmission System

In this paper,the six connecting rod transmission system is taken as research object,and its' dynamic analysis is carried out.The key of vibration damping in the six connecting rod transmission system is the rubber ball joint.From the point of view of the finite element,the mechanical properties of the rubber and the simulation parameters of the rubber material are obtained.Then the three direction stiffness of the single rubber ball joint is analyzed,and the three direction stiffness equation of the rubber ball joint is obtained.On this basis,the overall structure performance of the six connecting rod transmission system is analyzed,including the movement check between parts,the coupling stiffness analysis and the torsional vibration analysis.Finally,the dynamic response analysis of the six connecting rod transmission system is carried out in the case of the excitation of the rail road surface,and the different rotational speeds and different rubber ball passes are explored.The influence of section on dynamic response of six connecting rod transmission system has certain practical significance and value.The main contents of this paper are as follows:(1)Test and analysis of mechanical properties of rubber materialsThe rubber materials have complex mechanical properties and constitutive models.In order to obtain the LS-DYNA simulation parameters of rubber materials,the standard samples of rubber materials are designed.The tensile compression and dynamic shear tests are carried out to obtain the stress-strain curves of the axial tensile compression and the shear stress strain hysteresis loops in the dynamic shear.The parameters needed for the simulation are obtained by fitting the curve,which lays the foundation for the analysis of rubber ball joints.(2)Finite element analysis of the stiffness of rubber ball jointThe rubber ball joints are used as the basic damping units in the six connecting rod transmission system.The radial stiffness,deflection stiffness and torsional stiffness are commonly used to characterize the rubber ball joints.The main parameters affecting the stiffness of rubber ball joints are the rubber thickness and the pre-compression shrinkage.By calculating the three direction stiffness values of rubber ball joints under different rubber thickness and different pre-pressure shrinkage,the surface equation describing the three direction stiffness of rubber ball joints is obtained,which can quickly calculate the three stiffness values from the thickness and pre-pressure shrinkage of rubber ball joints,which lays the foundation for the subsequent analysis of the six connecting rod transmission system.(3)Structure and torsional vibration analysis of six connecting rod transmission system.Each component in the six connecting rod transmission system needs to satisfy a certain clearance relationship before interference.The inner spindle in the system is a moving body with various degrees of freedom.The inner spindle is connected with the outer spindle and the wheel axis through two six connecting rod couplings,and the radial stiffness,axial stiffness,deflection stiffness and torsional stiffness of the six connecting rod coupling are analyzed.Finally,the vibration differential equations are established for the torsional vibration of the six connecting rod transmission system,and the characteristic frequency and the modes of the system are obtained when the free vibration of the damping free and the free vibration with damping is obtained.(4)Track Irregularity AnalysisThe track irregularity is analyzed,and the mean,standard deviation,kurtosis,skewness and probability density function of track irregularity are calculated by statistical method in the time domain,and the track irregularity is analyzed by power spectral density function method in the frequency domain.The wavelength length and density contained in the smoothing process provide boundary conditions for the subsequent analysis of the dynamic response of the six connecting rod transmission system.(5)Dynamic response analysis of six connecting rod transmission systemIn the simulation of the actual operating conditions,the transient analysis of the six connecting rod transmission system is carried out under the consideration of the track irregularity.The dynamic response of the six connecting rod transmission system at different speeds is calculated,and the influence of the speed on the vibration of the system is explored,and the dynamic response of the system is calculated under the different rubber ball joints,and the optimal rubber matching with the system is found.