摘要: | 本研究使用直徑0.09 mm之鑽頭鑽削PCB電性檢測專用型治具針盤,透過田口實驗方法,設定轉速、進給率、鑽削方式、切削液等四種控制因子之不同水準值組合,進行實驗分析,利用荷重元、非接觸式量測儀量、孔位精度分佈圖軟體,求取鑽削推力、孔位精度分析與孔徑精度分析等數據,得到最佳鑽削工作參數組合,並對刀具壽命的影響進行驗證實驗。 本研究依據田口法直交表設計9組鑽削實驗,從實驗結果中觀察到鑽削力大小會影響鑽孔孔數的數量,並與鑽頭磨耗息息相關。將量測各組實驗孔位精度與孔徑精度的數據,利用田口實驗方法計算S/N比,得知具有最佳孔位精度的加工參數組合,為A2B2C1D3,即A2轉速為12,000 rpm、B2進給率為6,000 mm/min、C1鑽削模式為(a) 深孔鑽削循環G83、D3切削液比為1公升油: 30公升水;而具有最佳孔徑精度加工參數組合,為A2B1C3D2,即A2轉速12,000 rpm、B1進給率5,000 mm/min、C3鑽削模式(c) 斷屑鑽孔切削循環G73、D2切削液比為1公升油: 20公升水。將這二組最佳工作參數組合進一步進行驗證實驗,實驗結果顯示這二組參數組合在鑽削推力、孔位精度與孔徑精度的表現上,確實優於前面9組的表現,確認了田口分析法的有效性。而這二組參數組合的表現,又以後者更為優異,亦即A2B1C3D2這組參數組合為本研究鑽削PCB電性檢測專用針盤的最佳加工條件。 ;The purpose of this study is using a 0.09 mm-diameter drill to investigate the drilling characteristics in an in-circuit-test (ICT) probe plate for printed circuit board (PCB). Through Taguchi Method, four control factors, namely rotational speed, feed rate, drilling method, and cutting fluid, are selected to conduct designed experiments and analyze the results of drilling force, drill hole position precision, accuracy of hole diameter, and drill life. Accordingly, an optimal combination of working parameters for the given drilling task is determined and verified.
A Taguchi Orthogonal Array is selected to design and conduct 9 runs of drilling experiment. Experimental results indicate that drilling force plays an important role in determining the number of holes drilled and wear of drill. Taguchi Method is then applied to calculate the S/N ratios of the data in measuring drill hole position and diameter. As a result, the optimal control factor combination for drill hole position precision is A2B2C1D3, i.e. A2 with rotational speed of 12,000 rpm, B2 with feed rate of 6,000 mm/min, C1 with drilling mode of (a) deep-hole drilling cycle, G83, and D3 with cutting fluid ratio of one liter of cutting fluid and 30 liters of water. On the other hand, the optimal combination of control factors for accuracy of hole diameter is A2B1C3D2, i.e. A2 with rotational speed of 12,000 rpm, B1 with feed rate of 5,000 mm/min, C3 with drilling mode of (c) chip breaking drilling cycle, G73, and D2 with cutting fluid ratio of one liter of cutting fluid and 20 liters of water. Two more experiments using the drilling parameters A2B2C1D3 and A2B1C3D2 are conducted and the results indicate that such two combinations of control factors indeed generate a better performance than the originally designed 9 runs of drilling experiment. The verifying experiments also show that the A2B1C3D2 combination generates better results than the A2B2C1D3 combination. The overall comparison reveals that A2B1C3D2 is the optimal combination of working parameters for drilling holes in the given ICT probe plate of PCB. |