复合式镗铣加工中心滑枕变形分析与补偿研究

Research on deflection analysis and compensation of ram of boring-milling machining center

以复合式镗铣加工中心为研究对象,针对其大行程滑枕的挠曲变形误差问题,提出一种新型的变形补偿方法—液压拉杆补偿法,首先利用有限元分析的方法得到滑枕挠曲变形的分布规律,以及滑枕的变形量与滑枕行程之间的关系曲线;然后基于材料力学的理论分析得出拉杆补偿力的初算值,结合有限元分析方法与多项式最小二乘法拟合得到拉杆补偿力与滑枕行程的关系曲线;最后对其补偿结果进行分析得出:该方法准确预测了滑枕挠曲变形的分布规律,以及滑枕的挠曲变形误差得到了理想控制,显著提高了机床的加工精度。

In this paper,the ram of boring-milling machining center is taken as the research object. A new method that hydraulic pull rods compensation is proposed to solve the problem of deformation compensation of long stroke ram of boring-milling machining center. Firstly,the method of finite element analysis is used to get the laws of ram deformation and the relationship curve between the ram deformation and the stroke of ram. Secondly,the preliminary calculation value of pull rods compensation force is derived based on the theoretical analysis of material mechanics. The relationship curve between compensation force and the stroke of ram is obtained by finite element analysis and polynomial least squares method. Finally,the analyzed results are as follows: the laws of ram deformation distribution is accurately predicted by the used method, the deflection error of the ram is well controlled,and the machining precision is significantly improved.