以接觸點實現刀具轉換補償應用於PC-BASED五軸工具機之研究

在製造產業不斷要求及進步下，五軸工具機逐漸取代三軸工具機，無論加工效率、品質或是利潤，都可以有顯著的提升。加上現在電腦的發達，利用電腦提供切削相關、使加工更便利的程式有如雨後春筍般湧現。以往五軸加工從加工圖產生加工路徑時，所花的時間會因為加工精密度的設定而有所不同，大致上精密度要求越高的加工，產生路徑的時間也就越多。如果已產生之路徑所選用的刀具與實際切削刀具不同，使用者就必須回到電腦使用CAM軟體，正確設定刀具後，再次產生路徑才可得到正確之路徑，所費時間不斐。本文利用UG可提供之接觸點的資料，加上刀具路徑檔本身提供之刀尖點及刀軸向量等資料，演算出球刀、端铣刀及圓鼻刀三種典型刀具在單一種工具機上所產生的切削路徑相互轉換之方法，實際展現在PC-based之控制器上，讓使用者不必再因為刀具尺寸或類型設定之問題，再花時間到CAM軟體重新計算刀具路徑，而是在控制器上快速的透過視窗化介面進行轉換及代替，甚至在控制器上利用OpenGL建立之虛擬機台進行模擬。本文利用單一刀具產生的刀具路徑檔，經由視窗化界面計算後，便可以快速得到切削結果相近且相同類型刀具但不同尺寸，或是不同類型刀具之刀具路徑檔，接著再透過實體模擬切削軟體VERICUT進行驗證比對，並實際加工取得結果。

關鍵字

刀具補償；接觸點；切削點

並列摘要

Under manufacturing industry's constant demand for progress, the five-axis machine tool has gradually replaced the three-axis machine tool, and substantially increased the processing efficiency, product quality and business profits. With the rapidly advancing computer technology, the efficient numerical control programs related to cutting technology are booming. In the past, the time spent in the five-axis processing to generate a tool path based on the engineering drawing varies according to the setting precision of the parameters, generally speaking a processing with higher demand on precision would cost more time to generate the tool path. If the cutter selected for the generated tool path is different from the actual one, the user would have to get back to the CAM software to modify the related settings, and then redo the tool path generation process. This is a highly time consuming cycle. This study uses the contact point’s data provided by UG, coupled with the cutter's tip point and tool axis vector data provided by the cutter location file, to deduce an algorithm of bi-directional conversion of the cutter location files with three typical cutters - the ball cutter, flat-end cutter and ball nose cutter. This paper demonstrates how a PC-based controller can save users time by not having to get back to the CAM software to recalculate the cutter location due to the unmatched setting of cutter size or type. Instead, through a developed Windows interface on the controller, users can make quick conversion and replacement, and even use the OpenGL to establish a virtual machine for simulation on the controller. In this paper, a stand-alone cutting tool is used to generate a cutter location file. Through a Windows interface, the developed algorithm allows users to get an approximate cutting result with a cutter of same type but different size or with a cutter of different type. And then the solid cutting software VERICUT is used for verification, followed by a real machining to get experimental results.

並列關鍵字

Cutter compensation ； Contact point ； Cutting point

參考文獻

[1] D. N. Reshetov, V. T. Portman, 1998, “Accuracy of Machine Tool”, ASME press, New York.

Google Scholar

[2] Y. Takeuchi, T. Watanabe, 1992, “Generation of 5-axis Control Collision-Free Tool Path and Postprocessing for NC Data”, Annals of the CIRP, Vol. 41, No. 1, pp.539-542.