應用機械振動模態解析軸承初始損壞之自動監測系統

An Automatically Monitoring System for Bearing Defect by Using Mode Analysis of Mechanical Vibration

沈毓泰(Yuh-Tay Sheen) ； 陳威昇(Wei-Sheng Chen)

《中華民國振動與噪音工程學會論文集》 2015 (2015/06) Pp. 121-125

摘要

本研究以分析軸承振動模態間之包絡訊號特性，建立「軸承初始損壞之自動監測系統」，可應用於自動監測軸承之初始損壞，以因應未來在機械自動化、甚至無人化後，對機械系統損壞之自動監測需求。本研究之研究方法主要是藉由機械系統之結構振動特性分析，以量測分析軸承振動訊號中任兩模態振動訊號特性，利用線性最小平方分析（Linear least squares analysis）來進行兩振動模態訊號之調解分析，並計算此二模態包絡訊號間之相關係數值，以做為軸承損壞之量化診斷指標。由文獻研究發現，損壞軸承之振動訊號，其模態包絡訊號之間都具有密切的相關性。此乃由於在軸承損壞發生時損壞敲擊會激發多個振動模態，因而產生高頻調變振動訊號，故其模態解調之包絡訊號間，在統計上之相關係數值會較大；反之，正常軸承之振動訊號特性，則來自軸承加工過程之表面波紋，其波紋特性為低頻，並無法激發高頻調變振動訊號，故模態解調之包絡訊號間，其相關係數值則會較小。

關鍵字

軸承監測 ； 包絡訊號 ； 振動模態 ； 相關係數值

並列摘要

In this paper, an automatically monitoring system for bearing initial defect by using vibration mode analysis of mechanical system is presented. The system could be applied in the initial defect diagnosis, and this kind of automatic diagnosing technique would be an important issue for the application of automatic manufacturing system in the future. Based on the vibration mode analysis of mechanical system, the linear least squares analysis is applied in the parameter estimation of two designated vibration modes. Accordingly, the correlation coefficient between the envelopes derived from the two designated vibration modes could be a diagnosis index of bearing initial defect. It is because a bearing defect would excites multiple vibration modes. Thus, the correlation coefficient would be a larger value of approaching one, when there is a running condition of bearing defect. On the other hand, the correlation coefficient would be a smaller value of approaching zero, when there is a running condition of bearing defect.

並列關鍵字

Bearing monitoring ； Envelope ； Vibration mode ； Correlation coefficient