刀具剛性與切削精度關係之研究

Study of Relationship between Cutter Stiffness and Machining Accuracy

傅甘己(gan-jii fuh)

指導教授 ： 王世明

中原大學/工學院/機械工程研究所/碩士(2004年)

https://doi.org/10.6840/cycu200400021

摘要

切削刀具之撓度變形是造成工件加工產生誤差最主要因素。而刀具撓度變形大小是依刀具剛性好壞決定，剛性越差，刀具易產生變形，也容易產生切削振動，因而造成工件切削精度及表面粗糙度不良。影響刀具剛性好壞的因素為刀具的直徑大小、螺旋槽數量、挾持長度。本研究是利用建立端銑刀撓度及慣性矩數學模型，來探究刀具挾持長度與刀具剛性之間關係。本研究主要是研究發展一個模型，提供使用者決定最好刀具挾持長度，而使切削加工精度達到最精確。此外，不同刀具挾持長度，其靜態、動態剛性也會不同，因此造成刀具切削時產生振動大小也不同，因而影響工件的表面粗糙度；影響工件表面粗糙度除了刀具剛性之外，切削加工條件也是重要因素。所以本研究利用不同刀具挾持長度配合各種切削加工條件做實驗，來比較驗證前面推導之模型。

關鍵字

表面粗糙度 ； 端銑刀 ； 撓度

並列摘要

Deflection of cutter occurred during machining process introduces errors to the machined workpiece. Cutting vibration due to Low stiffness of cutter will also deteriorate the surface roughness of the workpiece. Factors, such as diameter, number of flutes, and cutter length, influence the static/dynamic stiffness of a cutter. In this study, mathematical model of moment of inertia for end mills was developed to explore the relationship between cutter stiffness and cutter length. The analysis based on the developed model can provide the information for users to decide the allowed maximum cutter length for precise machining. In addition, because different cutter lengths give a cutter varying static/dynamic stiffness that can influence the occurrence of cutting vibration to affect the machined surface roughness, the influence of cutter length to surface roughness with different machining parameters were also studied in this thesis. To verify the simulated phenomenon, several cutting experiments in which different clamping cutter lengths incorporated with different machining parameters for the comparison of machining accuracy were conducted.
Keywords：End Milling、Deflection、Surface Roughness

並列關鍵字

Deflection ； Surface Roughness ； End Milling

參考文獻

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