This invention relates to an axial fan housing having a metallic shielding grating covering an air passage opening, wherein {TAIL ~ the grating} is formed with a series of vane like guide bars arranged in {HEAD ~ two or more concentric circular series} 
This invention relates to an axial fan housing having a metallic shielding grating covering an air passage opening , wherein { TAIL ~ the grating } is formed with a series of vane like guide bars arranged in { HEAD ~ two or more concentric circular series }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD