加工中心主轴回转误差衰退概率模型

Probabilistic Modeling for Spindle’S Rotating Accuracy Decline of Machining Center

根据加工中心主轴可靠性虚拟试验技术的需要,以NBP1100型立式加工中心主轴为例,提出了一种以零件尺寸为误差源的主轴回转精度衰退模型。本文首先对旋转精度的灵敏度影响因素进行的量化分析,结果表明套筒与轴承的间隙尺寸误差、前后轴承的径向游隙对主轴回转精度影响最大;基于此,本文根据企业提供的零件图纸,引入轴承磨损规律,建立了一种可概率化的主轴回转误差衰退模型分析,并结合NBP1100主轴的具体参数,得到了主轴回转误差在任意运转时刻的概率分布,验证了该方法的可行性。本文为可靠性虚拟试验研究提供了一定的指导作用。

In this paper, according to the need of virtual testing technology of machining center spindle, a spindle rotation precision propagation model with the dimension of the parts as the error source is established by taking the spindle of the NBP1100 type vertical machining center. The factors influencing sensitivity of the model is quantitatively analyzed. The analyzing result indicates that the size error of the gap between the sleeve and bearing, and the internal clearance of bearings, has the greatest impact on the spindle rotation accuracy. On the basis of this, according to the drawings provided by the enterprise and the mechanical wear law, a probabilistic analysis method of the decline curve of the rotation accuracy model is established. Through integrating actual parameters of spindle, the probability distribution of the rotation error of the spindle at any time is obtained. The example shows that the method is feasible.