Research On Dynamics Of Herringbone Planetary Gear Considering Torsion Flexibility

The subject comes from the national key research and development plan project "High-performance gear dynamic service performance and basic test"(project approval number: 2018YFB2001300)and the National Natural Science Foundation of China project "Research on transient contact characteristics and anti-gluing load resistance of herringbone planet gear transmission" Approval number: 51975078).The herringbone planetary gear transmission system has a compact structure,high space utilization rate,high transmission ratio and transmission efficiency,and strong carrying capacity.Under heavy-duty operating conditions,it has comprehensive technical indicators that are much higher than other transfer systems.Due to the structural characteristics of herringbone teeth,the dynamic characteristics of the left and right single-sided helical gears are not exactly the same during actual operation,and the torsional flexibility between the left and right single-sided helical gears will affect the system dynamic characteristics.Therefore,the research of the herringbone planetary gear transmission system considering torsional flexibility has important theoretical and practical application value for controlling the vibration and noise of the transmission system and improving the transmission performance of the system.This article takes the herringbone planetary gear transmission system as the research object,considering the flexibility of the transmission system,mainly the torsional flexibility between the left and right side single helical gears of the sun gear and the inner ring gear,and using the lumped-parameter method to establish the torsional flexibility The dynamic model of the herringbone planetary gear transmission system,and at the same time,the dynamic simulation analysis model was established with the help of virtual prototype.The influence of torsional flexibility on the time-varying meshing stiffness and transmission error of internal and external meshing pairs is analyzed.The influence mechanism of torsional flexibility changes on the dynamic characteristics of the transmission system is studied.The main research contents of the paper are as follows:(1)Based on the gear meshing principle,comprehensively considering the meshing phase in the herringbone planetary gear transmission system and analyzing the torsional flexibility between the left and right single helical gears,introducing the Euler-Bernouli beam element theory to establish the herringbone planetary gear transmission system centralized parameter model.(2)The calculation method of the time-varying meshing stiffness of the herringbone gear is obtained according to the gear tooth contact theory.An analysis model of the transmission error of the herringbone tooth including the cumulative error of the tooth profile is established.The effect of torsion flexibility between the left and right single helical gears of the herringbone gears on the meshing stiffness and transmission error of the herringbone planetary gear transmission system are analyzed,the influence of the sun gear axial slide on the meshing stiffness and transmission error of the herringbone planetary gear transmission system are analyzed.(3)The vibration equation of the undamped herringbone planetary gear transmission system is derived,and the relationship between the natural frequency of the system and the vibration mode is obtained.The influence of the torsional flexibility between the left and right teeth of herringbone gear and axial slide of sun gear on the free vibration characteristics are studied.(4)Taking the torsional flexibility between the left and right single helical gears of the herringbone gears and the time-varying meshing stiffness and transmission error under the axial slide of the sun gear as excitations into the dynamic analysis model.The influence of the torsional flexibility between the both side of the herringbone gear and the axial slide of the sun gear on the dynamic characteristics of the system are analyzed...