Research On Dynamic Characteristics For Herringbone Gear Transmission With Friction

With the advantages of excellent bearing capacity,ignorable axial force and stable transmission,herringbone gears are widely applied in such aeras as aerospace and so on.Friction goes hands in hands with all sorts of transmission systems,which costs about one-third of disposable energy.Friction contributes to over-half failure of mechanical parts and serious accidents of mechanical equipment.Friction has an unignorable impact on mechanical transmission systems.Dynamic characteristics of herringbone gear transmission are discussed with friction taken into consideration.The influence of centering error and tooth tip modification on dynamic characteristics of herringbone gear transmission are analysed.The main contents are as follows:(1)The dynamic characteristics of herringbone gear transmission are analyzed.The influence of various of excitation are analyzed.Dynamics model and equations of herringbone gear transmission systems with friction excitation are established.Many test computation is carried out in turn to optimize the dynamics model and qeuations.The dynamics model is nondimensionalized to speed up the computation.During the calculation,the dynamics model is descended to one-order differential equations set,the number of arguments is decreased to increase the accuracy and efficiency.A computation method,which can be applied to various kinds of tooth profile parameters,of herringbone gear time varying contact line length or the time varying contact line length of each side of nodal line is proposed to avoid computational error of periodicity.The time varying meshing force is calculated on the basic of the time varying contact line length.Dynamic responses of herringbone gears transmission are calculated,and the dynamic characteristics of herringbone gear transmission are analyzed.(2)The dynamic characteristics of herringbone gear transmission with friction excitation are analyzed.The time varying friction excitation is calculated on the basic of the time varying contact line length of each side of nodal line.Friction excitation is applied to herringbone gear transmission.Dynamic responses of herringbone gears transmission with friction excitation are calculated by runge-kutta algorithm.Time varying meshing force and distortion of gear are discussed to make the dynamic characteristics clear.The time varying meshing force and distortion of gear are compared between the condition that friction excitation or damping excitation is taken into consideration and the condition that they are not.How do friction excitation and damping excitation influence the herringbone gears transmission are discussed.(3)The dynamic characteristics of herringbone gear transmission with both friction excitation and centering error are analyzed.Centering error is aided to herringbone gears transmission with friction excitation.A computation model of time varying contact line length with centering error is established.The dynamic characteristics of herringbone gears transmission with centering error are compared with the dynamic characteristics of herringbone gears transmission system with no centering error.The time varying meshing force of herringbone gears transmission system with different centering error are compared with each other to discuss the influence of centering error value size.(4)The dynamic characteristics of herringbone gear transmission with both friction excitation and tooth modification are analyzed.Tooth tip modification is aided to herringbone gears transmission with friction excitation.Time-varying mesh stiffness of herringbone gear transmission with tooth tip modification is calculated.Dynamic characteristics of herringbone gear transmission with different tooth tip modification are analysed.The influence of tooth tip modification on dynamic characteristics of herringbone gear transmission is discused.The influence of friction,tooth tip modification,excitation centering error are analyzed.The results is of a certain value for studies on herringbone gear dynamic analyses and design of herringbone gear transmission systerms.