煞車抖振傳導效應之分析與改良

The Effect of Vibration Transmission on Brake Judder Reduction

唐建嘉(Chien-Chia Tang)

指導教授 ： 傅增棣

國立臺灣大學/工學院/機械工程學研究所/碩士(2007年)

https://doi.org/10.6342/NTU.2007.01426

摘要

近年來由於人們對於乘車舒適性的要求越來越高，使得車廠對於煞車抖振的現象也逐漸重視；煞車抖振一般認為是因為碟盤厚度的變化所造成，因此常見的處理方式多為更新碟盤或研磨碟盤表面。然而此兩種方法會在一段時間的使用之後，重覆發生煞車抖振的現象而無法完全根治。基於以上的問題，本研究嘗試運用動態模擬分析軟體來建構完整的煞車振動傳導路徑模型，並利用理論方程式與實車測試數據加以檢驗，再藉由校正後的電腦模型進行轉向與懸吊系統關鍵參數之敏感度分析，透過在傳導路徑中系統參數特性之改良，尋求煞車抖振現象可行的改善方案。由分析成果得知，煞車碟盤厚度變化會造成煞車扭力之起伏，而左右輪煞車扭力起伏之相位差與下控臂前後方向運動的共振放大現象，為方向盤圓周方向振動的主要成因；此外，增加前懸吊下控臂後襯套的剛性係數、阻尼係數與方向盤的轉動慣量，均可有效減少因煞車抖振所導致的方向盤振動。

關鍵字

煞車抖振 ； 虛擬原型 ； 電腦輔助工程

並列摘要

Owing to the higher standard of driving comfort, brake judder has become an important issue in automotive design. It is, in general, caused by the variation of braking disk thickness (DTV). In tradition, the problem was solved by replacing or regrinding the disks, which can only have a temporary effect and will re-happen again after a period of use. Therefore, this research attempts to establish a model for brake judder transmission by virtual prototyping technique. Validated by theoretical equations of motion and field tests, sensitive analyses of key parameters in steering and suspension are performed and the measure for brake judder reduction is approached. It is found that DTV will induce the variation of braking torque. The phase difference between right and left front wheel torque variation and the resonance of lower control arm bushings are the main reasons of steering shimmy. Moreover, increasing the stiffness and damping of lower control arm rear bushing and the steering column inertia can effectively reduce the shimmy caused by brake judder.

並列關鍵字

brake judder ； virtual prototyping ； computer-aided engineering

參考文獻

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