大客車車體結構之安全性分析與研究

Safety Analysis and Research on the Car-body structure of Large Passenger Vehicles

池怡芬(Yi-Fen Chih)

指導教授 ： 林震

國立臺北科技大學/機電學院/精密機構設計產業研發碩士專班/碩士(2007年)

摘要

影響大客車車身結構安全之因素眾多，而大客車車身骨架結構之焊接長度、方式及品質的好壞將是直接影響整體骨架強度的因素之一。然而，目前國內相關業者對此卻甚少投入研發心力加以關切。本論文依照國內特定廠商提供之大客車設計圖用ANSYS軟體，建構有限元素模型，此模型採用簡化模型Solid元素，以ANSYS分析與並國內車輛法規制定安全規範做相互比對，驗證大客車安全結構，探討真實之結構安全效果，另推導出以下幾點客車應有的安全設計：
1.對於車身骨架之斷面要求，因考慮車身縱骨架與橫骨架的不同受力，其車身橫骨因受扭力最好是以封閉性截面為佳。
2.整車骨架至少應有三道由車頂骨架至車（左、右）側立柱再至地枕結構並與大梁之完整車身骨架結構以形成對大客車車身之安全保護設計。
3.車側骨架之立柱設計原則應以力之連續性作為首要考量原則，若確有未逮之際，則應妥善運用補強板或斜撐。
4.邊窗內框四周設計應以圓角取代直角，但圓角補強板之橫向面不宜熔接，以避免應力集中。
希能提供國內大客車車體製造廠對於結構改善方案和大客車全車安全防護設計及國內車輛法規訂定之參考。

關鍵字

大客車 ； 大樑 ； 車身結構 ； 應力 ； 應變 ； 有限元素

並列摘要

There are many factors affecting the car body structural safety of large passenger vehicles. One of the major factors lies in welding whose length, technique and quality are directly related to the structural strength of vehicle body. This critical factor, however, has received hardly any attention from local bus companies. Based on the design plan of a specific large passenger vehicle and related regulations of vehicle safety as standards, the thesis adopts ANSYS software to build models of limited and simplified beam elements to examine the structural safety of an actual large passenger vehicle.
1. Consider the different level of force on the vertical and horizontal framework, the horizontal framework should adopt sealed cross-section.
2. No less than three steel columns should exist from roof structure to the left and the right side framework then link to frame structure of floorboard, which is connected with entire framework and formed protection to the vehicle body.
3. Principle on designing frame structure of sides should consider the continuity of stress as its first priority. Use of strut rods and balance rods are necessary if some structures aren’t strong enough.
4. As for frame structure of windows, its four corners should use arch-shape instead of right angle. To avoid stress concentration, welding on the crosswise of arch strut rods should not be done.
Results of the research can be expected to provide references for local large passenger vehicle body builders in hope of improving car body structural safety and for the government in drafting relevant safety regulations.

並列關鍵字

Large passenger vehicle ； frame ； car-body structure ； stress ； strain ； Finite Element method

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