封闭差动行星传动系统中心轮动力学浮动量分析

基于集中参数振动理论,建立采用中心轮浮动的封闭差动行星传动系统动力学模型.考虑支撑的弹性变形、啮合齿轮副的时变啮合刚度激励和齿轮误差激励.计算系统两级中心轮的浮动量,获得齿轮误差、支撑刚度与系统两级中心轮浮动量间的关系曲线,分析误差、支撑刚度对系统两级中心轮浮动量的影响.研究结果表明:系统两级中心轮浮动量随误差增大而增大;差动级中心轮的浮动量远比封闭级的浮动量大;差动级齿频误差引起的中心轮浮动量远大于偏心误差引起的浮动量,差动级中心轮浮动量对齿频误差比偏心误差敏感;可以适度减小系统两级中心轮的支撑刚度来提高两级中心轮的浮动能力；为实现差动级中心轮较高的浮动能力,差动级中心轮应采用较小的支撑刚度.

Analysis of dynamic floating displacement of center gear for encased differential planetary train

Based on the vibration theory of the concentrated parameter,a dynamics model which adopted the floating frame of the center gears for the encased differential planetary train was set up.The elastic deformation of the bearings,the time-varying meshing stiffness and the gear errors were considered in the model.The center gears’ floating displacements of the two stages were calculated and some curves of the relationships between the errors(the bearing stiffness) and the center gears’ floating displacements were obtained.The impacts of the errors and bearing stiffness on the center gears’ floating displacements were analyzed.The results show that the center gears’ floating displacements of the two stages change largely with the increase of the errors.The center gear’s floating displacements of the differential stage are much bigger than those of the encased stage.In differential stages,the floating displacements caused by the meshing-frequency error are far greater than those by the run-out errors,and the floating displacements are more sensitive to the meshing-frequency errors than the run-out errors.The center gears’ bearing stiffness of the two stages can be decreased moderately to increase the center gears’ floating displacements.In order to realize the larger floating displacements of the center gears of the differential stage,the center gears’ bearing stiffness of the differential stage should be smaller.