直齿轮铣削加工的铣刀与工件切触区域仿真分析

Cutter Workpiece Engagement Calculations for Milling of Spur Gear with Ball-End Cutters

针对圆柱直齿轮的多轴铣削精加工,提出一种基于三维实体造型技术的球头铣刀与工件瞬时切触区域(简称切触区域)仿真分析方法。建立齿轮铣削运动模型,准确描述铣刀和工件之间的运动关系;在齿轮齿廓精确模型描述的基础上,基于等残留高度法实现球头铣刀刀具路径规划;通过刀具扫掠体与过程工件模型之间进行布尔求差得到更新过程工件模型;依据切触区域的球面几何特性,从更新过程工件几何模型中识别出切触区域;利用平行于刀具轴线的平面将切触区域进行切割,得到切触区域角度区间。切削试验结果表明,仿真切触区域结果与实际加工结果具有一致性,验证了仿真计算的有效性和准确性;球头铣刀与工件切触区域的准确提取,为齿轮铣削力、刀具磨损等物理量的精确预测奠定了基础。

This paper presents a new solid model for calculating the cutter-workpiece engagement(CWE)boundaries in the ball-end finish milling process of spur gear.The kinematics model between the milling cutter and gear is first described.Based on the model of spur gear tooth,a new method to generate constant scallop height tool paths for ball-end milling is developed.Updating in-process workpiece is constructed by performing a subtraction boolean operation between the in-process workpiece and tool swept volume model;The CWE is extracted from the updating in-process workpiece based on spherical geometry;The engagement angles are calculated by Slicing the CWE surfaces with the parallel planes along tool axis;The confirmation of the validity and accuracy of the proposed method has been accomplished by the contrast between simulation results and the results from gear milling experiments,expressing a faultless agreement between them.The extraction of the cutter-workpiece engagement provide the whole geometrical information needed for further research,such as prediction of the cutting forces and tool wear development.