Research On The Vibration Characteristics Of Hollow Cylindrical Roller Bearings

Rolling bearing is one of the most widely used basic mechanical components,and it has an important joint role in the operation of the industry and even the national economy.The vibration characteristic of the rolling bearing is a comprehensive reflection of the dynamic performance quality of the bearing,which has a direct effect on the performance of the whole machine.In the precision machinery such as machine tools,because of the high precision of the spindle rotary precision,it is the most important to improve the vibration performance of the bearing.The vibration of the rolling bearing not only affects the operation precision of the whole mechanical system,but also the source of the noise.Therefore,the vibration and noise reduction of the rolling bearing is called the important problem that the bearing industry of our country must face.Hollow cylindrical roller bearing has the characteristics of high rotation precision and high rigidity,which is very suitable for high speed working conditions and precision machinery.Because hollow roller has better elasticity than solid roller.it can absorb shock and vibration due to bearing defects to some extent,so hollow cylindrical roller bearing has better vibration characteristics.In this paper,the research on vibration characteristics and influencing factors of hollow cylindrical roller bearings is carried out,which provides theoretical guidance for vibration reduction and noise reduction of bearings and improving slewing accuracy.Based on the theory of elasticity,the deformation and stress distribution of hollow cylindrical roller are obtained and verified by ABAQUS finite element simulation.On this basis,the kinematic relationship and radial load distribution of the bearing are calculated,and the influence of different factors on the radial load distribution of the bearing is analyzed.The research shows that a certain roller hollowness can reduce the excessive contact load of roller caused by excessive bearing speed,and the bearing roller should be generally full.Then based on the elastohydrodynamic lubrication theory(EHL),the contact pair contact mechanics model of the roller and raceway roller bearing of hollow cylindrical roller bearing is established.On this basis,the Lagrange equation is used to establish the micro vibration equation of the hollow cylindrical roller bearing under the lubrication and dry contact conditions,and the mass matrix of the bearing is solved.The damping matrix and the stiffness matrix.The vibration characteristics of bearing,including dynamic load,dynamic stiffness,natural frequency and amplitude frequency characteristics,are studied.The effects of different parameters including structural parameters and working conditions on the bearing vibration characteristics are compared and analyzed.The study shows that lubrication has a very important influence on the vibration characteristics of hollow cylindrical roller,but no matter whether it is lubricated or not,the hollow cylindrical roller bearings do not have flexible vibration.At last,the model of bearing defect excitation is set up,and the bearing vibration is simulated by MATLAB,and the vibration of bearing under the excitation of single defect and continuous defect is simulated,and the attenuation of the impact in the bearing is explored.The influence of bearing structure parameters on the vibration induced by defects is studied preliminarily.