摘 要

本設(shè)計是為了設(shè)計一種能對滾動軸承進行故障診斷的簡易系統(tǒng)。滾動軸承是機械設(shè)備中最常用也是最容易損壞的零件之一。旋轉(zhuǎn)機械中發(fā)生的故障有70%是由滾動軸承的故障而引發(fā)。滾動軸承有很多損壞形式，總地來說分為對承內(nèi)圈、外圈、滾動體以及保持架的損壞。這些損傷必然會引起軸承在運動過程中產(chǎn)生沖擊，但由于沖擊持續(xù)時間短，能量發(fā)散的頻域范圍廣，落在振動頻率范圍內(nèi)的能量分量很小。因此，需要通過某種方法對這些復(fù)雜的信號加以處理，才能提取我們所需要的故障信號。通過對故障信號的頻域分析，就很容易獲得故障沖擊波的波形，將故障信號頻率與我們事先設(shè)定的故障特征頻率進行比較，從而確定軸承故障的發(fā)生部位。該系統(tǒng)設(shè)計中利用共振解調(diào)原理對沖擊故障進行診斷檢測。本文著重講解了對滾動軸承振動信號的分析問題，講述了適用于平穩(wěn)信號及線性變換方法的傅立葉變換的頻譜分析，并重點講述包絡(luò)分析的原理。最后利用軟件LabVIEW開發(fā)平臺設(shè)計出一套基于PC-DAQ的虛擬儀器測試系統(tǒng)。


關(guān)鍵詞：滾動軸承，故障診斷，信號處理，虛擬儀器


ABSTRACT

This project is in order to design a system which can implement state monitor and fault diagnosis. Rolling bearing is the most useful and both the most vulnerable part in mechanical equipment. The 70% of rotating machinery failure is because of bearing fault. There are a number of mechanisms that can lead to bearing failure, including the inner ring, the outer ring, the rolling elements, and the cage. These failure would induce impact when bearing works. But because of the short duration of impact, the frequency spectrum of energy is broad in scope and the energy signal in the scope of vibration frequency is faint. Therefore, in order to distill the fault signal we needed, the original signal we get should be disposed by some measure. It is easy to get the impact wave through the frequency spectrum analysis to fault signal. Compare the wave to the academic frequency of fault signal calculated in advance, it would be clear that which component is in failure. Demodulation Resonance Principle is used to diagnose the fault signal in this project. The analysis to vibration signal of rolling bearing is presented in this paper, including the Fourier Transform, an applicable technique to smooth signal and linear transformation, besides, the envelope analysis is emphasized. Finally, a virtual instrument system based on PC-DAQ and Labview platform is presented.


Key words： Rolling bearing, fault diagnosis, signal processing, virtual instrument


目 錄

中文摘要 Ⅰ
ABSTRACT Ⅱ
1 緒論 1
1.1 課題的提出及意義 1
1.2 課題的研究背景 1
1.3 故障診斷系統(tǒng)技術(shù)的發(fā)展趨勢 2
1.4 主要設(shè)計內(nèi)容 3
1.4.1 主要設(shè)計過程 3
1.4.2 本論文主要內(nèi)容 3
2 滾動軸承的結(jié)構(gòu)及故障機理 4
2.1 滾動軸承的結(jié)構(gòu) 4
2.2 滾動軸承的失效形式 4
2.3 軸承故障的振動檢測方法 5
2.3.1 滾動軸承的故障機理 5
2.3.2 滾動軸承異常時的特征頻率 6
3 滾動軸承振動信號分析 8
3.1 概述 8
3.2傅立葉變換及其應(yīng)用 8
3.2.1傅立葉變換 8
3.2.2傅立葉變換的應(yīng)用 9
3.3 包絡(luò)分析 10
3.3.1 包絡(luò)分析基本原理 10
3.3.2 包絡(luò)解調(diào)技術(shù) 11
3.3.3 包絡(luò)分析的實現(xiàn)方法 14
3.3.4 包絡(luò)分析的發(fā)展及現(xiàn)狀 15
4 檢測儀總體設(shè)計 16
4.1 設(shè)計綜述 16
4.2 硬件設(shè)計 16
4.2.1 硬件總體構(gòu)成 16
4.2.2 直流電動機調(diào)速系統(tǒng)的選擇 17
4.2.3 傳感器的選擇及布置 20
4.2.4 信號調(diào)理電路 21
4.2.5 數(shù)據(jù)采集卡 22
4.3 軟件設(shè)計 23
4.3.1 軟件介紹 23
4.3.2 軟件總體構(gòu)成 24
4.3.3 振動信號處理程序 25
4.3.4 LabView程序設(shè)計 26
5 總結(jié) 28
參考文獻 29