Abstract: There is provided an impeller for a centrifugal fan which rotates around an axis extending from one side to the other side. The impeller includes a main plate, a plurality of blades each having one side portion located at the one side and the other side portion located at the other side, the one side portion being connected to a first surface of the main plate, and a connecting ring which connects the other side portions of the blades. A first circumferential groove to which a first balance weight is attachable is formed in an outer circumferential portion of a second surface of the main plate facing toward the one side. A second circumferential groove to which a second balance weight is attachable is formed in the connecting ring. An annular raised portion is formed on the first surface at a portion corresponding to the first circumferential groove.

Abstract: Herein disclosed are an impeller and a centrifugal fan having the same. The impeller includes a cup-shaped metallic hub having a cylindrical portion. The hub includes a flange extending outwardly from an edge of the cup, a plurality of resin vanes disposed above an outer portion of the flange and coaxially with the cylindrical portion, and an annular part made of resin supporting the plurality of resin vanes thereon and holding the outer portion of the flange embedded therein.