车用发动机凸轮轴轴承松脱的故障特征提取  

Fault feature extraction of automotive engine camshaft bearing loosening

作　　者：喻菲菲[1] 杜灿谊[2] 

机构地区：[1]广东技术师范学院机电学院,广州510635 [2]广东技术师范学院汽车学院,广州510635

出　　处：《现代制造工程》2015年第4期33-37,共5页Modern Manufacturing Engineering

基　　金：国家自然科学基金项目(51305085);广东省高等学校优秀青年教师培养计划资助项目(Yq2014110);广东技术师范学院校级科研项目(13KJY12)

摘　　要：车用发动机凸轮轴轴承松脱故障使得凸轮轴受力不均而引起冲击力,导致凸轮轴附近机体表面出现异常振动和显著噪声。通过对某发动机凸轮轴轴承松脱故障的试验测试,提取缸盖振动加速度信号进行时域分析,发现有明显的周期性冲击;利用小波包分解至较高频段并做解调分析,解调谱的故障激励频率非常显著。分析结果表明,凸轮轴轴承松脱故障有中高频调制现象,可综合利用时域分析、频谱分析和小波包分解与解调分析进行相应的故障特征提取。Automotive engine camshaft bearing loosening fault will cause impact force because of uneven stress on camshaft , so abnormal vibration and noise appear on the body surface near the camshaft .By the test for engine camshaft bearing loosening fault,vibration acceleration signal of cylinder head is collected to analyze in time domain ,cyclical shock can be seen .Then wave-let packet decomposition method is used to decompose the signal and demodulation analysis is applied to higher frequency band signal,fault excitation frequency in the demodulation spectrum is very obvious .The analysis result shows that camshaft bearing loosening fault would cause mid-high frequency modulation phenomenon ,it could extract the corresponding fault feature by com-positely using time domain analysis ,frequency spectrum analysis and wavelet packer decomposition and demodulation analysis .

关 键 词：凸轮轴轴承 松脱 小波包分解 解调 故障特征 

分 类 号：TK407[动力工程及工程热物理—动力机械及工程] TK418