本研究探討離合器接合過程所產生頓車之問題，藉由改變離合器摩擦材料之銅纖維添加與木質纖維添加以及成型壓力、成型溫度與成型加熱持溫時間，以5因子3水準之L’18直交表，製作18組試件。由實驗所量測到的振動、扭矩與轉速變化，利用摩擦特徵、扭矩比值與頓車頻率，所得之結果，搭配離合器摩擦材料接觸壓力變化和溫升理論模型與離合器接合過程之振動訊號碎形分析。最後以實驗設計之田口方法與變異數分析，利用摩擦特徵、扭矩比值以及摩擦係數三者之全距與隨循環增加之變動斜率，找出影響18組試件，貢獻率最高之材料添加或製成參數，以及摩擦材料配方最佳配置。
由離合器接合過程中振動原始訊號推算出之頓車頻率，其陡升之循環與接觸壓力之最大壓力比所發生之循環，兩者與摩擦特徵與扭矩比值之結果對應，發生循環之時間越早，頓車現象越嚴重。由接觸力學分析結果計算之最大壓力比越大，摩擦特徵與扭矩比值之表現也越差，頓車現象越嚴重。離合器摩擦材料配方最佳化之結果顯示，成型壓力為本研究18組離合器摩擦材料配方中影響摩擦特徵、扭矩比值與摩擦係數三者之全距與變動斜率，最顯著之製程參數，而成型壓力為影響摩擦特徵之重要製程參數，銅纖維添加量為影響扭矩比值之材料參數，其添加量越多，越不容易發生頓車。
藉由判斷頓車產生時間之早晚與振動訊號之碎形分析，相較於摩擦特徵( )與扭矩比值( Ts / Td )之大小以及隨循環次數增加之變化，較無法分辨離合器摩擦材料之優劣，其原因為頓車在振動上之行為是短時間且較無規律性的。

This research investigates the judder phenomena during the engagement of motorcycle centrifugal clutch. By changing the composite of friction materials including copper fiber and methyl cellulose fiber and manufacturing parameters including molding pressure, molding temperature, and molding duration, 18 specimens was made to test according to L’18 orthogonal array of 5 factors and 3 levels. In order to compare the result of friction characteristic, torque ratio, and judder frequency with contact mechanism, temperature rise analysis, and fractal analysis of vibration signal, the torque, rotational speed, and vibration signals was measured during the experiment. The most important factor and the optimum level can be found by using of the Taguchi method and ANOVA, and the objective of optimization are the range and the changes in slope of friction characteristic, torque ratio, and coefficient of friction.
Comparing to the friction characteristic and the torque ratio, the clutching number of having the 1st judder and the maximum contact pressure will be earlier if the judder phenomena get worse. The result of contact mechanism analysis shows that the larger the maximum pressure ratio is, the worse the friction characteristic and torque ratio are, on the other hand, the worse the judder phenomena is. Molding pressure is the most important manufacturing parameter in this research, it affects the performance of friction characteristic, torque ratio, and coefficient of friction. Judging from the clutching number of having the 1st judder and the fractal analysis is less desirable compared to the friction characteristic and the torque ratio. Because the judder phenomena is a short-time and not a periodically vibration.

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