A pitch deviation compensation technology for precision manufacturing of small modulus copper electrode gears

The machining accuracy of a copper electrode gear (CEG), especially the pitch deviation of CEG, is affected by the wear of the ball end mill (BEM) with the increase of the length of milling path. Based on the error mapping principle, this work focuses on the influence of BEM wear on pitch deviation. In order to dynamically compensate the influence of the BEM wear on pitch deviation, a novel milling pitch deviation compensation model was proposed based on the formation mechanism and measurement principle of pitch deviation. To ensure the uniform wear at the milling edge of the BEM during the milling process, BEM wear was firstly copied to the pitch deviation according to the tooth-by-tooth milling strategy. Then, the BEM wear curve was fitted based on orthogonal experiments and multiple linear regression. According to the wear curve, an offline compensation method was adopted to compensate for the pitch deviation caused by BEM wear. In addition, the reverse compensation principle was used to compensate for the normal deviation of BEM milling path. Finally, the compensation model was verified by milling experiments. Pitch deviation met the requirements of Levels 4∼\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\sim $\end{document}5 in GB/T 38192-2019. The model can be used to guide the milling process of CEG.