應用碎形路徑於五軸銑削加工機之研究

Application of Fractal Path in Five-axis Machining

陳可君(Ke-Jun Chen)

指導教授 ： 陳政順

國立臺北科技大學/機電學院/製造科技研究所/碩士(2009年)

摘要

本研究以自動化的概念結合現在加工複合機的特色，將輪磨、研磨與拋光作業加入五軸銑削加工機中，有效利用工具機自動換刀的特性，使工件能在一次夾持下，完成模具的開發。並引用碎形路徑(Fractal Path)進行加工，嘗試改善傳統往復式路徑X、Y方向不均勻的問題，探討碎形路徑應用於五軸加工機之可行性。再對各階數的碎形路徑作分析，比較不同階數的扇型高度、弦高誤差與加工路徑總長，給予碎形階數選擇上的依據。
在碎形路徑的建構上，首先利用Matlab軟體撰寫，再與Unigraphcis CAD/CAM軟體結合，最後利用半徑為20 mm 之凹半球形曲面來驗證碎形路徑之可行性。本次實驗所使用的模具胚料為NAK80。實驗結果顯示，以Hilbert Chamfer七階路徑銑削加工之凹半球曲面，其表面粗糙度約可達1.26μm，真圓度約可達0.0241mm，經過輪磨、研磨與拋光後表面粗糙度改善至0.43μm，真圓度0.0195mm；以Peano Chamfer五階路徑銑削加工之凹半球曲面，其表面粗糙度約可達1.37μm，真圓度約可達0.0255mm，經過輪磨、研磨與拋光後表面粗糙度改善為0.47μm，真圓度0.0217mm，由此可證明本文之研究成果與方法值得參考。

關鍵字

碎形路徑 ； 五軸加工 ； 模具研磨與拋光

並列摘要

In this study, the concept of automatic processing sequences is applied to the machining of mold with NAK80 die steel, that is, the milling, grinding, lapping and polishing operations are all performed on the same five-axis machining center. In order to improve the uneven tool path distribution found in traditional reciprocating path, the fractal path is used to create the cutting tool path for machining the mold with a concave hemisphere surface. The feature of several different types and order of fractal path are analyzed and evidenced based on the parameters like scallop height, chord height error, and path length.
For the generation of cutting tool path can be used in five-axis machining center, the two dimensional fractal path chosen are programmed with the Matlab, the date are then transferred to the Unigraphics CAD/CAM system for mapping the date into the concave hemisphere surface of mold, and post-processed to the NC code required. The experimental results shows that the surface roughness is form 1.26μm to 0.43μm, and the roundness is form 0.0241mm to 0.0195mm, after the grinding, lapping and polishing of mold for the seven-order Hilbert chamfer machining path. And the surface roughness is form 1.37μm to 0.47μm, the roundness is form 0.0255mm to 0.0217mm for the five-order Peano chamfer machining path. It is believed the results and method developed in the study give a good reference for industrial application.

並列關鍵字

Fractal Path ； Five-axis Machining ； Mold Lapping and Polishing

參考文獻

4 梁宏彬，應用五軸加工機銑削球形曲面之探討，碩士論文，國立台北科技大學製造科技研究所，台北，2007。

5 黃繼輝，應用田口法於五軸CNC銑削加工製程之最佳化參數設計，碩士論文，國立台北科技大學製造科技研究所，台北，2008。

36 http://www.sfy-tech.com.tw 盛方源科技股份有限公司

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