汽車扣件扭力值之研究

Study of Torque Setting for Automotive Fasteners

卓聖益(Shang-Yi Juo)

指導教授 ： 黃秀英

國立臺北科技大學/機電學院/車輛工程系所/碩士(2010年)

https://doi.org/10.6841/NTUT.2010.00273

摘要

一般零件在組裝的過程中，為求效率都是以氣動扭力扳手直接鎖緊，既沒有按照規定的扭力，也沒有注意扣件（Fastener）所要鎖緊的零件材質為何，往往造成螺栓變形量伸長導致組合件的表面材料的破壞，日後更會因為材料疲勞，而產生間隙，扣件失去維持組合件的夾緊力，慢慢出現組合件鬆動或是噪音的現象，此在車輛結構上更是常見。
本研究目的是針對車輛上的扣件，以扭力角度破壞試驗法（Torque-Angle to Failure）的實驗方法與扭力角度署名曲線分析（Torque Angle Signature Analysis），為扣件設訂一個適合的扭力值。本實驗架設了車輛電動伺服精密扭力扳手（DC Nut Runner）搭配Quality Productivity Modularity（QPM）電腦軟體，紀錄螺栓在鎖緊時的數據，透過扭力角度署名曲線分析，將讀取的數據以圖示的方式呈現，估算適合的扭力範圍，再進一步以設定扭力值組裝零件，並驗證組合件之殘餘扭力。
實驗所得資料，會以統計的計算方式設定所需的扭力值，以便能夠將實驗結果實際地運用在汽車零件的組裝上，提升實驗整體之可靠度，本研究之樣本全部採用汽車上的零件。研究的結果比較修護手冊裡的扭力值，並提出適當的修正。

關鍵字

扣件 ； 夾緊力 ； 扭力角度署名曲線分析 ； 車輛電動伺服精密扭力板手

並列摘要

For easier and cheaper implementation, fasteners are often tightened with impact wrenches instead of DC Nut Runners. The specified torque values are hardly followed, nor have the characteristics of the joints been paid attention to. Over time under- or over-torque fasteners could result joint loosing or failure, and not able to maintain proper clamp forcess. These joints assembly could gradually loose up and introduce squeaks rattle, vibration or noise.
The purpose of the study was to develop a methodology to set up torque SPEC for automotive fasteners using torque-angle to failure tests and torque angle signature analysis. A DC nut runner along with Quality Productivity Modularity（QPM）software, was used for fastener torque tests, and data recording. The data was processed to illustrate signature of joint based on the signature profiles. Torque specification of a joint was determined. Residual torques was also studied to evaluate joint relaxation behaviors over time.
In the thesis, a statistic approach was used to derive the required joint torques. To demonstrate the proposed method was practical and reliable, automotive parts were used. The results of studies were compared against the torque setting specified in the vehicle service manual.

並列關鍵字

fastener ； clamp force ； torque angle signature analysis ； DC Nut Runner

參考文獻

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