Dynamics Analysis Of Gear Transmission System With Meshing Beyond Pitch Point And Experimental Verification

Comparing with spur gear transmission,the actual meshing line of gear transmission system with meshing beyond pitch point located in one side of the pitch point can avoid the shock vibration caused by the changing direction of friction.In this paper,parameters optimization design,time-varying meshing stiffness calculation,dynamic analysis,experimental verification and nonlinear dynamic study of the gear transmission system with meshing beyond pitch point are developed.Nonlinear dynamic analysis of planetary gear transmission drive with meshing beyond pitch point are researched.The gear parameters are optimized by objective function of minimum mass,the model considering time-varying meshing stiffness,time-varying bearing stiffness,time-varying friction,in which time-varying meshing stiffness fitted by Fourier series method is computed by using material mechanics method.The models of friction coefficient are analyzed and compared,and the EHL model of theory friction coefficient is determined.Considering the influence of the time-varying bearing stiffness and physical conditions of CL-100 gear testing machine,dynamic response of time domain and frequency domain are solved by numerical integration.The verification experiment is carried out with the CL-100 gear test rig,and the vibration signals are measured in different working conditions.The signals are analyzed based on the wavelet theory.The analysis results show that gear transmission with meshing beyond pitch point can improved the dynamic characteristics of the system.The two-dimensional non-linear dynamics model of a gear transmission with meshing beyond pitch point with six degrees is established.Time-varying meshing stiffness,time-varying bearing stiffness,time-varying friction,backlash and bearing clearance are considered.The global bifurcation characteristics caused by input speed,backlash,bearing clearance and damping are investigated.The maximum Lyapunov exponent which led to chaos characters is studied.The parameters of planetary gear system are optimized.The two-dimensional non-linear dynamics model of planetary gear transmission with meshing beyond pitch point is established.Phase angle,time-varying stiffness and load distribution among gear teeth are calculated.A two-dimensional non-linear dynamic model considering time-varying meshing stiffness,time-varying bearing stiffness,time-varying friction,backlash and bearing clearance are established.Besides,the global bifurcation characteristics caused by input speed,backlash,bearing clearance and damping are analyzed.