Dynamic Modeling Of Gears With The Error Of Rotating Axis And Study On Dynamic Characteristics Of Planetary Gear Trains

Planetary gears have been widely used in aerospace,ship,oil,energy,automotive,metallurgy,engineering machinery and other industries.With the development of modern science and technology and the increasing concerns to environmental problems,it requires a higher dynamic performance requirements,such as high speed,large load,long life and low noise.However,due to the influence of manufacturing error,the load distributions between the planets are unevenly distributed and vibration,noise and the stress increase.The existence of manufacturing error has become an important factor restricting the development of planetary gears to the high speed,high reliability and low noise.Therefore,this paper studies dynamic modeling of planetary gears with typical manufacturing error and analyzes the relationship between typical manufacturing error excitation and the vibration response and dynamic mesh force of planetary gears.It has significant academic value and engineering significance for the design of highly reliable,low vibration and noise planetary gears.The purpose of this paper is to model the planetary gear with manufacturing error and analyse the dynamic response characteristic.It starts with displacement excitation induced by manufacturing error and investigates a series of manufacturing error excitation and corresponding dynamic response.The main research contents include:1.Aiming at problem of nonlinear vibration of planetary gear with typical manufacturing error(carrier hole position error and eccentric error)and backlash,a nonlinear dynamic model of planetary gear having manufacturing error and backlash is established.It considers the phenonmen of tooth wedge caused by presence of manufacturing error breaking the limitation of three contact states of meshing gears in the traditional nonlinear planetary pigear model,that is working surface meshing,non-working face meshing and tooth separation.The influence of carrier pin hole postion error on the frequency response curve and vibration characteristic and load sharing characteristic variety due to gear eccentricity and carrier pin hole position error are obtained.2.Aiming at the problem that the mesh postion,center distance and line of action(LOA)variety are affected by carrier pin hole position error and gear eccentricity error,a new mesh stiffness excitation and displacement excitation model with eccentric error and carrier pin hole position error is established based on the instantaneous position of gears.The new model can simulate the mesh stiffness variety caused by the position error and gear eccentricity error.The influence of carrier pin hole position error and eccentricity error on the mesh stiffness and dynamic response of planetary gear set is revealed under different error configurations.3.A bending-torsional-pendular dynamic model of planetary gear is established using independent spring in parallel representing tooth contact.It makes up the shortcomings of the present model of spur planetary gear ignoring the effect of the pendular vibration.The influence of the misalignment error of carrier and planet on the meshing force,vibration characteristics and trajection of the sun gear is revealed.4.Aiming at dynamic modeling of flexible ring gear planetary gears with typical manufacturing errors,a coupling dynamic model of the planetary gear train with flexible ring gear and typical manufacturing error is established based on the theory of Timoshenko beam theory and influence coeffecients method.The coupling effect of flexible ring gears and error excitation,e.g.eccentricity error,carrier pin hole position error adn tooth profile modification,are investigated.It overcomes the problem that it is difficult to utilize the traditional meshing stiffness model of ring-planet with flexible ring gear describing coupling effect of multi-planets engagement and error excitation.