Abstract: To solve the problem of machining accuracy and efficiency in the processing of gears free-form milling,a method was proposed to manufacture involute cylindrical gears by considering tooth surface accuracy characteristics.A mathematical model was established to investigate the tool path with respect to geometric characteristic of gear surface according to the theory of free-form envelope and gear generation.By considering the differential geometric characteristics and accuracy characteristics of tooth surface,the optimized tool path related to the characteristics of tooth surface accuracy was studied.The equation of involute angle of tooth profile with respect to residual error of the tooth surface was derived.For a validation,an experiment was performed using a universal 4-axes machine center with standard end mill.The results showed that the proposed method could improve the accuracy of main meshing area of involute cylindrical gears with the same machining efficiency of free-form milling.

Key words: involute cylindrical gears, free-form milling, tooth surface accuracy, tool path optimizing

摘要： 针对柔性包络铣齿过程中加工效率与加工精度之间的矛盾,提出一种考虑齿面精度特性的渐开线圆柱齿轮包络铣削加工方法。根据空间包络铣削理论和齿面展成成形过程,建立通用刀具的空间曲面包络成形数学模型,并求解含残高差的包络铣齿刀位点;综合考虑齿面的微分几何特性和精度特性,研究铣齿刀具路径规划与齿面精度特性优化匹配关系,构建了渐开线齿廓展开角度与齿面残高差之间的曲线方程;在通用的四轴加工中心上采用通用立铣刀的包络铣齿加工实例验证了所提方法的正确性。实例分析结果表明,所提方法在保证包络铣齿加工效率的前提下,提高了渐开线圆柱齿轮主啮合区域的加工精度。

关键词: 渐开线圆柱齿轮, 包络铣齿, 齿面精度, 刀路优化