Patent ID: 8953315
Filing Date: 2015-02-10
Classification: F04D

Abstract:
1. An axial fan comprising: an impeller arranged to rotate about a central axis, and including a plurality of blades centered on the central axis, arranged to project radially outward, and arranged in a circumferential direction; and a housing including a side wall arranged to include openings at first and second axial ends thereof and arranged to surround an outer circumference of the impeller, the side wall including at least one flat portion, and a substantially square or substantially rectangular flange arranged to project radially outward from an outer circumferential surface of the side wall, the side wall including an opening end at the axial end thereof on an inlet side and another opening end at the axial end thereof on an outlet side, the flange being arranged on the opening end on the inlet side or on the opening end on the outlet side; wherein the side wall includes at least three slit groups and at least three slitless portions, each of the at least three slit groups includes a plurality of slits arranged in the circumferential direction and arranged to extend through the side wall from an inner circumferential surface to the outer circumferential surface thereof; and two of the at least three slit groups are respectively provided in two adjacent corner portions of the side wall in a first radially extending half portion of the flange with the at least one flat portion provided between the two adjacent corner portions and including one of the at least three slitless portions, while a remaining slit group of the at least three slit groups is provided in a portion of the side wall in a second radially extending half portion of the flange, the first radially extending and second radially extending half portions being divided at a line parallel or substantially parallel to two opposing sides of the flange and passing through the central axis.