The Influence Of The Momentum Wheel Bearing Guide Surface Texture On The Dynamic Performance Of The Cage

At present,China’s space technology has made great progress,but at the same time there have been many new problems.As a key component of the spacecraft attitude control system,the momentum wheel plays an important role in the satellite operation.In this process,the stability of the momentum wheel bearing has attracted wide attention,and the lubrication characteristics of the bearing are closely related to its stability.In recent years,many studies have shown that micro-texture can change the surface topography,affect the contact shape and lubrication state of the friction pair surface,improve the wear-reducing and bearing capacity of the friction pair,and improve the service life of the friction pair.Therefore,this paper considers adding micro-texture on the bearing guiding surface to improve the lubrication effect between the cage and the guiding ferrule,improve the dynamic stability of the cage,provide theoretical guidance for the improvement of the performance of the momentum wheel bearing,and then provide a solution for improving the momentum wheel’s Work accuracy and service lifeIn order to obtain the solution algorithm for the lubrication analysis of the surface texture of the guide surface,based on the Reynolds equation,the lubrication analysis model of the rolling bearing guide surface considering the surface texture was established,and the cylindrical texture and the distribution were analyzed under different texture distribution densities.The influence of the spherical crown texture on the lubrication characteristics and bearing characteristics of the guiding surface.The results show that the cylindrical texture and the spherical crown texture have certain influence on the lubrication characteristics of the guiding surface,but will not change the overall change trend.The eccentricity and the maximum oil film thickness decrease with the increase of the speed,and they increase with increasing load,and the deviation angle and the minimum oil film thickness are exactly opposite;under the same speed and load,the bearing capacity of the bearing is relatively stable when the texture distribution is loose,but the oil film thickness is small.In order to obtain the most obvious type of texture for the lubrication effect of the bearing guide surface under actual working conditions,the influence of the depthdiameter ratio of the cylindrical texture and the radius of the spherical-shaped texture on the lubrication characteristics of the rolling bearing guide surface was analyzed.Under the required working conditions,the bearing lubrication characteristics and bearing characteristics are improved to the most obvious texture.It is found that for the lubrication characteristics of the bearing under the cylindrical texture,it can be seen that the lubrication performance of the bearing guiding surface is improved when the depth of the texture is relatively large;the radius of the spherical crown texture is larger under the same external conditions.When the bearing guiding surface has better lubrication effect and the bearing capacity is enhanced,when the rotating speed is 2000r/min and the radial load is 10 N,the cylindrical texture with relatively large depth should be selected.In order to explore the influence of friction coefficient and axial load on the running stability of cage under actual working conditions,a dynamic model of rolling bearing based on ADAMS was established.The axial force and friction coefficient of cage were analyzed under different working conditions.The effects of stability include cage speed,cage/rolling element impact force,cage/outer ring impact force,cage/outer ring friction torque,and cage center of mass trajectory.It is found that with the increase of the friction coefficient,the fluctuation range of the cage rotation speed is larger and larger;the larger axial force and the friction coefficient both increase the friction torque of the guide ferrule to the cage.At the same time,reducing the axial load of the bearing and reducing the friction coefficient can improve the running stability of the cage to a certain extent.It can be seen from the above research that the surface texture has a positive effect on improving the lubrication state between the cage and the guide ferrule,which can improve the friction state of the momentum wheel bearing and the dynamic stability of the cage,and provide a function for improving the working precision and service life of the momentum wheel.The solution measures provide theoretical support for the long reliability improvement and life growth of spacecraft.