第五章 結果與討論
5.2 密封分析預測與實驗結果比較
利用二合一連接器矽橡膠墊圈承受下壓量0.2mm 條件下，關鍵元素之接觸應 力與時間之關係，接續輸入表4-3 列舉之洩漏率模型所需幾何與環境參數與矽橡膠 墊圈之抗拉強度(St) 6.5MPa，藉由 MATLAB [1]中迴歸分析之非線性最小平方法 (nonlinear least square)功能調整式(4-18)內 5 個材料參數Ci (i=1, 5)，並與第三章所 述相對應量測結果進行擬合，將迴歸結果整理列於表5-3。接續預測墊圈承受下壓 量0.3mm 與 0.4mm 條件下之壓力損失百分比，圖 5-12 為數值分析結果與實驗量 測平均結果比較圖。如前所述，測試規範為經過1800 秒後，密閉腔體洩漏氣壓值 不得大於初始氣壓值之百分之二，表5-4 顯示三種下壓量於 1800 秒後，模擬與量 測所得壓力損失百分比，兩者差異約為2.8%至 10%。進一步預測耳機座連接器墊 圈承受三種下壓量條件下之壓力損失百分比，與其相對應實驗量測平均結果比較，
如圖5-13 所示，表 5-5 顯示三種下壓量於 1800 秒後，模擬與量測所得壓力損失百 分比，兩者差異則約為4.5%至 7.8%。研究結果顯示，針對此兩連接器而言，矽橡 膠墊圈均需承受下壓量略大於0.4mm 之條件，方得使其壓力損失百分比符合規 範。
表5-3 洩漏率預測模型迴歸係數
C1(mm4) C2 C3 C4 C5 3.62×10-9 74.8 1.31×10-12 -26.1 -1.01
表5-4 二合一連接器於 1800 秒壓力損失百分比
承受下壓量(mm) 數值分析(%) 實驗量測平均值(%)
0.2 10.4 10.7
0.3 6.28 5.71
0.4 2.42 2.43
表5-5 耳機座連接器於 1800 秒壓力損失百分比
承受下壓量(mm) 數值分析(%) 實驗量測平均值(%)
0.2 2.50 2.71
0.3 1.97 2.07
0.4 0.85 0.89
圖5-12 二合一連接器密封分析與量測所得之壓力損失百分比比較圖
0 1000 2000 3000 4000
Pressure loss percentage (%)
Time (s) Experiment - 0.2mm
Experiment - 0.3mm Experiment - 0.4mm Regression - 0.2mm Prediction - 0.3mm Prediction - 0.4mm
0
0 1000 2000 3000 4000
Pressure loss percentage (%)
Time (s) Experiment - 0.2mm
Experiment - 0.3mm Experiment - 0.4mm Prediction - 0.2mm Prediction - 0.3mm Prediction - 0.4mm
第六章 結論
本研究針對矽橡膠墊圈應用於電子連接器之密封性能提供一系統化分析流程，
首先將矽橡膠墊圈材料製成之標準樣本施以單軸壓縮鬆弛負荷，藉以獲得矽橡膠 墊圈材料組成律參數。接續導入有限元素分析，獲取二合一連接器矽橡膠墊圈承 受下壓量0.2mm 條件下，關鍵元素之接觸應力。搭配密封實驗之壓力損失百分比 量測數據，透過MATLAB [1]針對之自行提出洩漏率模型進行參數迴歸，接續預測 墊圈承受其餘較大下壓量條件下之壓力損失百分比，並與相對應實驗量測比較，
具備良好吻合度。為驗證本研究之流程合宜性，另針對採用相同墊圈材料之耳機 座連接器進行密封分析，預測墊圈承受三種下壓量條件下之壓力損失百分比，亦 與相對應實驗量測比較，獲致良好一致性，彰顯本洩漏率模型可有效評估電子連 接器之密封性能。
未來可依據本研究之成果，推廣至如 Liu 等人[14]之液體洩漏評估，其研究主 要裝置基本上係由兩壓克力板間夾一墊圈材料組成，壓縮墊圈負荷可由組裝兩壓 克力板之螺釘控制。墊圈上方形成一密閉腔體，液體藉由幫浦輸入此空間，同時 利用壓力感測器紀錄密閉腔體壓力。裝置前方架設一攝影機，觀察液體洩漏情形。
數值分析亦可遵循實驗設定進行模擬，進而提出適用於液體之洩漏預測模型，接 續將本研究流程導入進行相關實驗與驗證，並檢視於設計階段之其它具備密封性 能連接器，成信對於提升產品開發效率具備顯著助益。
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