Research On Multi-factor Coupled Dynamic Characteristics Of Beveloid Planetary Gear System

Compared with other planetary gear transmissions,2KH planetary gear system has simpler structure and wider range of applications.As a result,it has been widely used in engineering practice.With the improvement of ship performance,people have higher and higher requirements for the performance of gear transmission system.There is a complex coupling relationship among the exciting factors in the planetary gear system.The small change of the system design parameters may lead to complex changes in the dynamic response.Therefore,it is necessary to study the influence of the design parameters of 2KH beveloid planetary gear system on its dynamic response.In this paper,dynamic models considering friction factor of 2KH beveloid planetary gear system are established.The influence of parameters variation of planetary gear system on its dynamic response is studied from three aspects: vibration intensity,load sharing characteristics and motion stability.This paper summarizes the influence of various parameters on the performance of planetary gear transmission system,and provides reference for the design of planetary gear transmission system in practical engineering from the three aspects studied.In this paper,the lumped parameter method is used to establish the translation-torsion coupling model and the bending-torsion-axis coupling model of beveloid 2KH planetary gear system.In the process of establishing these models,some factors are considered comprehensively,including the time-varying stiffness of gear meshing,backlash,friction of tooth surface,static transmission error,which have great influence on the dynamic response of the gear system.On the basis of the established model,the dynamic equations of planetary gear system are deduced by means of Lagrange equation,and the coordinate transformation and dimensionless treatment of the equations are carried out.In order to obtain the time domain diagram and the excitation-displacement map,the dynamic equations of the bending-torsion-axis coupling model of the planetary gear system are solved.The vibration displacement amplitude is used as the index to measure the vibration intensity of the system.Taking the amplitude of vibration displacement as the index to measure the vibration intensity of the system,the influence of parameters such as meshing static transmission error,load size and load fluctuation on the vibration intensity of the system is studied.The parameters interval which is sensitive to the change of the corresponding parameters is found,which provides a reference for the economic and effective vibration reduction measures in engineering practice.On the basis of defining the load sharing coefficient of planetary gear transmission system,it is used as an index to evaluate the load sharing performance of the studied system.The bending-torsion-axis coupling dynamic equation of the system is solved,and by calculating the dynamic meshing force of each gear pair in the whole system,the load-sharing coefficient of each gear pair is calculated.Finally,the maximum load-sharing coefficient of each gear pair is taken as the load-sharing coefficient of the system.Comparing the load-sharing coefficients calculated by various parameter combinations,the best parameter combination interval for load-sharing of the system is found.The translational-torsional dynamics equation is solved to obtain the dynamic response of the system.The influences of parameters such as rotational speed,damping and transmission power on the motion stability of the system are studied by plotting the system's bifurcation diagram,phase diagram and Poincare diagram of specific working conditions.This paper summarizes the parameter intervals of bifurcation and quasi-periodic,chaotic and other complex motion states of the system when the parameters change,and provides suggestions for the realization of the stability of the system in engineering practice.