Patent ID: 8292588

Claim:
An impeller for use in a centrifugal fan, the impeller comprising: a support portion including a cylindrical outer circumferential surface coaxial or substantially coaxial with a center axis; and a plurality of blades independently arranged on the outer circumferential surface of the support portion and configured to draw in air along the center axis and expel the air radially outwards when rotated about the center axis together with the support portion; wherein at least two of the plurality of blades each include: a first blade portion connected to, and extending radially outwards from, the outer circumferential surface of the support portion, and at least one second blade portion including a radial inner end portion radially spaced apart from the outer circumferential surface of the support portion; and a connecting member arranged to connect the first blade portion and the at least one second blade portion; and each of the at least two of the plurality of blades is arranged such that the first blade portions are connected to only respective ones of the at least one second blade portions through only respective ones of the connecting members.