Tool Path Generation for Clean-up Machining of Impeller by Point-searching Based Method

• Published in: Chinese journal of aeronautics 2012-02, Vol.25 (1), p.131-136
• Main Authors: TANG, Ming, ZHANG, Dinghua, LUO, Ming, WU, Baohai
• Format: Article
• Language: English
• Subjects: clean-up; impellers; NC machining; point-searching; tool path; 刀具路径; 叶轮; 搜索工具; 清理加工; 球头立铣刀; 生成方法; 表面光洁度; 路径生成
• ISSN: 1000-9361
• DOI: 10.1016/S1000-9361(11)60371-3

Machining quality of clean-up region has a strong influence on the performances of the impeller. In order to plan clean-up tool paths rapidly and obtain good finish surface quality, an efficient and robust tool path generation method is presented, which employs an approach based on point-searching. The clean-up machining mentioned in this paper is pencil-cut and multilayer fillet-cut for a free-form model with a ball-end cutter. For pencil-cut, the cutter center position can be determined via judging whether it satisfies the distance requirement. After the searching direction and the tracing direction have been determined, by employing the point-searching algorithm with the idea of dichotomy, all the cutter contact （CC） points and cutter location （CL） points can be found and the clean-up boundaries can also be defined rapidly. Then the tool path is generated. Based on the main concept of pencil-cut, a multilayer fillet-cut method is proposed, which utilizes a ball-end cutter with its radius less than the design radius of clean-up region. Using a sequence of intermediate virtual cutters to divide the clean-up region into several layers and given a cusp-height tolerance for the final layer, then the tool paths for all layers are calculated. Finally, computer implementation is also presented in this paper, and the result shows that the proposed method is feasible.