TMT三镜系统Rotator组件轴承设计

Design of rotator assembly bearing in TMT tertiary mirror system

以TMT三镜系统为对象,对其中的Rotator组件用轴承进行了设计,并对轴承关键参数的选取进行了探讨。首先,通过分析三镜系统的运动模式确定了系统的受载状态;接着基于Hertz弹性变形理论,建立了双列角接触球轴承的载荷-变形公式,采用牛顿迭代法对轴向、径向、角位移量进行求解,得到每个钢球受载和变形的精确解;最后对该轴承设计中的一些关键参数选择对承载能力的影响进行了讨论。计算分析表明,在三镜工作角度范围内,光轴方向最大变形为0.022 mm,滚道面内各个方向变形小于0.042 mm,最大角变形量为3.5″,满足三镜系统的设计要求,并留有较大的设计裕度。建立的载荷分布方程及提出的参数选择原则对双列角接触球轴承的设计具有通用性,可适用于各种工况。

The bearing in Rotator assembly of TMT tertiary mirror system was designed, and the rule of parameter choice was discussed. Firstly, the load case of tertiary mirror system was analyzed, after that, the load-deformation equations of double-rows angular contact ball bearing were established and solved with Newton iteration method, the axial, radial and angular displacement were obtained, the load and deformation of every ball as also, the effect of different parameters were discussed at last. The result shows that, when the azimuth varies in 0°-65° , the displacement in optical axial direction is less than 0.022 mm, the displacement in rollaway plain is less than 0.042 mm, the maximum angular displacement is less than 3.5″, the design requirement is satisfied, there are enough margin compared to the index. The load distribution equation and parameter choice rule of double-rows angular contact ball bearing can be applied in different cases.