內藏式主軸之共振現象的理論探討與實際應用

王瑞昌

指導教授 ： 左培倫

國立清華大學/工學院/動力機械工程學系/碩士(2010年)

https://doi.org/10.6843/NTHU.2010.00390

摘要

本論文主要目的在提升內藏式高速主軸的轉速，在提高轉速的同時，如何避免轉速提升，所造成的較大振動振幅是首先須要考慮的問題；並且進一步的改變主軸系統的動態特性，使得振動量在所要求的範圍內是本文所要追求的目標。為了達到上述目標，本文先從研究現有可行的轉速下主軸(矩將科技的Iso 25內藏式主軸)的動態特性，預測出當轉速提升時的振動情形，從而改變原本系統的設計，避免較大的振動量。
產生振動的原因有很多種，解決不同的振動問題必須使用不同的方法，所以必須對所量測到的振動訊號做診斷，找出振動源。其中最大的問題來自於激振源頻率與自然頻率重疊造成的共振現象。而根據瀑布圖，這些激振力中，動不平衡激振力響應遠大於其他機振力的響應，此為本文所要探討的。
首先經由模態分析，可以得到主軸系統的自然頻率，主軸在不轉動下，實驗所得到的模態參數和理論建立的有限元素模型進行驗證，以得到較合理的模型，此模型再用以計算出系統轉動時的模態參數，以及改變設計參數時的變化。
本研究建立了提升主軸轉速的一個完整的研究與設計方法。對主軸各轉動零件的運動情形提供了數學模型，並從模擬上提供了系統各參數和主軸動態特性的關係，獲得有效的改善方法。

關鍵字

內藏式主軸 ； 模態測試 ； 共振 ； 有限元素

並列摘要

The purpose of this thesis is to upgrade Built-in high-speed spindle speed, while enhances the rotational speed, how to avoid the rotational speed promotion, creates the big vibration oscillation amplitude is the question which must first probably consider; And the further change main axle system's dynamic characteristic, causes the vibration quantity, in requests in the scope is the goal which this article needs to pursue. In order to achieve the above goal, this article starts from the research on the existing feasible rotational speed main axle's dynamic characteristic, Forecast works as the rotational speed promotion vibration situation, thus changes originally the systematic design, avoids the large vibration quantity.
There are many kinds of reasons for the vibration , to solve the different vibration problem, need to use the different method. Must therefore to gauge the vibration signal makes the diagnosis, discovers the vibration source. And the most major problem from overlap creates in the excitation source frequency and the nature frequency resonance effect. And according to the waterfall diagram, in these exciting forces, the response to the balanced exciting force is much bigger than other response, therefore this must discuss for this article.
First by way of the modal analysis, may obtain the main axle system's nature frequency. Compare the modal parameter from the modal analysis to the result of the simulation, the resonable mathematic mode can be moded. by obtains the reasonable model, this model can be used to calculate that the time the system rotation. as well as time change design variable change.
This research has established a complete research of the promotion for spindle speed and has provided system various parameters and the main axle dynamic characteristic relations from the simulation, obtains the effective improvement method

並列關鍵字

Motor built-in spindle ； modal test ； resonance ； finite element

參考文獻

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