Low-Frequency Biaxial Vibration Assisted Cutting Technology for Automatic Chip Breaking on Turning Metal materials

本論文開發的「低頻雙軸振動輔助斷屑裝置」延伸車削在低頻切削技術的雙軸加工應用。本裝置主要藉由兩顆壓電致動器的開關和一個倍率放大撓性鉸鏈機構帶動刀把進行X方向或Z方向或斜向的往復運動，端面車削和外徑車削可避免重新架設的麻煩。斷屑裝置零件數量少且倍率放大撓性鉸鏈機構為整體設計，可避免如傳統機構接觸面有背隙和磨耗的問題，進而提升運動精度。 斷屑裝置經模擬分析可得X和Z方向的輸出位移量為壓電致動器輸入位移量的2倍。結構之最大應力小於材料降伏應力250MPa，可防止機構產生永久變形；小於材料疲勞強度230MPa，則可提高裝置使用壽命。X和Z方向的剛性接近10N/μm，以減少因切削力所造成的變形。 本裝置可調變頻率範圍建議在100Hz內，經性能測試可知以250−的電壓訊號分別輸入至兩個壓電致動器，若調變頻率為100Hz 的X和Z方向的最大位移分別為33μm和19μm，放大倍率分別為2.2和1.3。以250−的電壓訊號同時輸入至兩個壓電致動器，若調變頻率改為100Hz時 X和Z方向的最大位移分別為36μm和29μm，放大倍率分別為2.5和1.9。 本裝置架於動力刀塔進行切削試驗，成功使單軸車削及雙軸同動車削的切屑斷屑，且預估的切屑長度與實際切屑長度相似。外徑和端面以及錐面的粗糙度符合精加工指標。This thesis developed the 'Low-Frequency Biaxial Vibration Assisted Chip Breaking Device' extended turning in low-frequency cutting technology for Biaxial machining applications. The device mainly by two piezoelectric actuator switch and a magnification of the flexible hinge mechanism to drive the tool to the X direction or Z direction or oblique reciprocating motion, turning face and turning the outer diameter to avoid the trouble of installing. This device have the fewer parts and the magnification of the flexible hinge mechanism for the overall design, to avoid the traditional body contact surface with backlash and wear problems, thereby enhancing the movement accuracy. The output displacement of the X and Z directions is two times the input displacement of the piezoelectric actuator by simulation analysis The maximum stress of the structure is less than 250MPa, which can prevent the permanent deformation of the material. If the fatigue strength is less than 230MPa, the life of the device can be improved. The stiffness in the X and Z directions is close to 10 N / μm to reduce the deformation due to the cutting force. The adjustable frequency range of the device is recommended within 100Hz. According to the performance test, it can be seen that the voltage signal of 250 - is input to the two piezoelectric actuators respectively. If the frequency of the adjustable frequency is 100Hz, the maximum displacements in the X and Z directions are 33μm and 19μm respectively, and the amplification ratio is 2.2 and 1.3, respectively. The voltage signal of 250 - is input to the two piezoelectric actuators at the same time. If the frequency is 100Hz, the maximum displacement in the X and Z directions is 36μm and 29μm respectively, and the amplification ratio is 2.5 and 1.9 respectively. The device was mounted on a power turret for cutting test, which resulted in the chip breaking of the uniaxial turning and the biaxial synchronous turning, and the estimated chip length was similar to the actual chip length. The roughness of outer diameter and end face and the cone meet the finishing index.摘要 i Abstract ii 圖目錄 vii 表目錄 x 第1章 緒論 1 1.1 研究動機與目的 1 1.2 研究進步性 3 1.3 專利分析 4 1.4 論文架構 5 第2章 文獻回顧 6 2.1 振動切削的背景 6 2.2 低頻切削的特色 7 2.2.1 切削熱量 7 2.2.2 切削力量 8 2.2.3 切削能量 9 2.2.4 刀具磨耗 10 2.2.5 界面摩擦 10 2.2.6 加工表面 11 2.3 低頻切削的應用 13 2.3.1 特殊材料的加工 13 2.3.2 切屑尺寸的控制 16 2.3.3 表面紋理的研究 17 2.4 低頻切削的方法 19 2.4.1 NC碼控制 19 2.4.2 工件振動 20 2.4.3 刀具振動 21 第3章 斷屑機制 28 3.1 調變(MODULATION)方向 28 3.2 刀具與工件的相對運動 29 3.3 模型建立與數學推導 30 3.4 理論驗證 34 3.4.1 振幅與進給量關係 34 3.4.2 與相位關係 35 3.5 切屑形成 36 第4章 斷屑裝置開發 38 4.1 設計原理 38 4.1.1 斷屑裝置設計 38 4.1.2 陶瓷壓電材料簡介 39 4.1.3 撓性鏈結機構簡介 40 4.2 ANSYS WORKBENCH結構靜態分析 41 4.2.1 材料參數與模型建立 42 4.2.2 網格設定 43 4.2.3 邊界設定 44 4.2.4 結果輸出 44 第5章 實驗測試 49 5.1 性能測試 49 5.2 切削測試 54 5.3 切削結果 57 5.3.1 加工切屑 57 5.3.2 切屑長度預估 58 5.3.3 加工表面 58 第6章 結論與未來展望 60 6.1 結論 61 6.2 未來展望 63 參考文獻 6