微CNC 綜合加工機研發與微元件製造研究

Development of Micro CNC Machine Center and Research of Micro Parts Machining

陳順同(Shun-Tong Chen)

指導教授 ： 廖運炫

國立臺灣大學/工學院/機械工程學研究所/博士(2005年)

https://doi.org/10.6342/NTU.2005.02850

摘要

本文研發一部具備一般微銑削、微高速銑削、微放電、微線切割及線上微量測功能的『多工型高精密4 軸微綜合加工機』，可用來製作微模具、微工具、微元件和微結構。機器的開發，於硬體部分，提出了複合傳動機構的雙主軸加工系統設計及第四伺服軸設計，主軸轉數可由0 至80,000rpm，視不同加工機制而選擇；高速轉軸已成功用於金屬微模具和高分子微模具的粗加工，中速軸用於一般微銑削加工，而低速軸用於微細放電加工。軟體方面，採用PC-Based 控制器，以C++ Builder 5.0 開發界面控制程式，完成了加工、編輯和線上量測等功能模組。於技術開發部分，在微放電方面，為加工各種微細電，本研究研發了一組新式WEDG 機構和捲線機構，不但適合各種直徑的銅線使用，銅線走線時也沒有跳線和疊線問題，可精密加工出各種造型的微電極或微探針，並大幅降低WEDG 的製作成本；在微線切割方面，開發出一組多向型微線切割放電加工機構，使微工件具有臥式、立式、傾角及反向等多方向的加工自由度，工件不需拆卸及再校正，可一次定位至加工完成。針對細線之張力，提出以磁力控制張力的方法，具有體積小、安定性佳、成本低和隔空作用無能量損失等優點，另外，亦提出線速度、線穩定度和伺服進給等控制策略，於實驗驗證均能達到應有的性能。在實際切割實驗上，成功地切割出節徑24µm 的小齒輪、周節133.5µm 的微齒條以及1.25×1.25×1.7mm 的複雜微塔結構，尺寸精度在1µm 以下，表面粗度也在0.64 µm 以內。在線上微量測方面，本研究提出利用一簡易的短路偵測原理，採用微加工機上現有的放電迴路，除去電容並使用極低的工作電壓和比較電壓進行量測；以0 級塊規進行量測精度的反驗證，及真平度、真圓度和圓柱度等的量測，所求誤差保守估計均在1µm 以內。最後利用研發出的機器，在多向型微線切割放電加工機構上加入銅線制振系統，並以反向切割模式搭配適當的線張力，成功地切割出寬21µm，長700µm，
深寬比達33 的柱狀陣列微型結構，以及厚10µm，面積300x745µm 的陣列微鰭片，尺寸精度和幾何精度均在0.5µm 以下，而表面粗度則在Rmax0.45µm 以內。本研究成功的開發出多工型高精密4 軸微綜合加工機，具創新性與市場潛力，於微加工領域將具貢獻。

關鍵字

微小高精密綜合加工機 ； 微銑削 ； 微高速銑削 ； 微放電 ； 微線切割 ； 微線上量測

並列摘要

In this paper a multi-function high precision tabletop CNC machining center formaking micro parts is developed. All the needed machining processes can be carriedout on the same machine without the need to unload, reload and eadjust the workpiece for subsequent process. Currently the functions of Micro CNC milling,Micro EDMilling, Micro Wire-cutting, and Micro on-line measuring have been accomplished and tested. In the developed machine a dual spindle design for Micro CNC milling, and for the manufacturing of icroelectrode and the following micro hole or die making by EDMilling, respectively is proposed and constructed. The
necessary software written in Borland C++ language is developed as well. The Micro CNC milling is tested by the use of a milling cutter of 0.1 mm diameter and by a special design diamond tool. Satisfactory results are achieved. The microelectrode is produced via WEDG process, and it is used for micro hole drilling and 3D micro parts manufacturing by micro EDMilling. In Micro wire-cutting a 20µm diameter fine wire is used. A novel mechanism that allows vertical/horizontal/slant angle wire cutting is designed. Micro parts such as outer gear, internal gear, rack, etc. having no taper angle on the machined part are successfully manufactured. A micro pagoda of size 1.25x1.25x1.7 mm is also produced to demonstrate the machine’s superior ability. Furthermore, based on the “short-circuit principle” and the micro probe manufactured by WEDG process, an on-line micro part measuring system to evaluate the flatness of the machined part, and the circularity and straightness of the micro-hole is developed and implemented.

並列關鍵字

tabletop CNC machining center ； micro CNC milling ； micro EDMilling ； micro wire-cutting ； micro on-line measuring

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