多点切触加工中的局部干涉分析

为了消除多点切触加工刀位计算的局部干涉,通过对中凹端铣刀和工件曲面之间的几何接触状况分析,得到了多点切触加工算法的局部干涉判别条件.利用微分几何得到了多点切触加工刀位中刀具和工件的交线在第一切触点处的曲率半径和刀具曲率半径的比值,结合局部干涉判别条件,得到无干涉的多点切触加工约束的解区域.结果表明无论曲面为何种样式,必须选择第二切触点在曲率较大的主方向附近的解区域中,再使用多点切触加工算法算出的刀位,才有可能不发生过切现象. 

Local interference identification of multi-point machining

In order to get rid of the local interference of the tool positions calculated using multi-point machining algorithm, the discriminant of local interference was derived after the analysis on the geometric match between the disc cutter with a concave end and the desired surface. The ratio of curvature radius of intersection curve of the disc cutter and the desired surface at the first contact point to the radius of the cutter, which was belonged to tool position calculated using multi-point machining method, was derived with differential geometry analysis. Combined with the discriminant of local interference, the solution areas of multi-point machining constraint immune to local interference were deduced. Results show that no matter what kind of surface was machined, the tool positions calculated using multi-point machining method would not be interferential with the desired surface locally if the second tangent contact point was selected in the solution areas of multi-point machining constraint, where the corresponding principle direction had larger surface curvature.