Abstract: A centrifugal fan includes: an impeller; an upper casing that is disposed above the impeller; a lower casing that is disposed below the impeller; an outlet port that is provided between the upper casing and the lower casing and from which an air suctioned by rotation of the impeller is discharged, wherein the upper casing is provided with a flange that protrudes in an outer radial direction of the impeller from an outer circumferential edge of the upper casing, and wherein the flange partially covers the outlet port when viewed from a direction perpendicular to a rotation axis of the impeller.

Abstract: A centrifugal fan includes: an impeller; an upper casing that is disposed above the impeller; a lower casing that is disposed below the impeller; an outlet port that is provided between the upper casing and the lower casing and from which an air suctioned by rotation of the impeller is discharged, wherein the upper casing is provided with a flange that protrudes in an outer radial direction of the impeller from an outer circumferential edge of the upper casing, and wherein the flange partially covers the outlet port when viewed from a direction perpendicular to a rotation axis of the impeller.

Abstract: There is provided a centrifugal fan including a casing having an upper casing with an opening and a lower casing with a recess, a motor disposed in the recess, and an impeller housed in the casing. The impeller includes an annular shroud formed with an inlet, plural blades which are arranged between the annular shroud and the lower casing, and a hub which is connected to respective inner sides of the blades. Each of the blades includes, at a pressure surface side, a first inclined surface which is inclined toward a negative pressure surface of the blade as approaching the lower casing from the annular shroud; and a second inclined surface which is provided closer to the lower casing than the first inclined surface, and is inclined toward the negative pressure surface at an angle steeper than that of the first inclined surface.