Patent ID: 7815419

Claim:
An impeller for a blower having: a circular support plate having a rotational axis; and a plurality of blades provided on a peripheral edge portion of the support plate, extending in parallel to the rotational axis and having a predetermined blade angle, the impeller comprising: a plurality of notches provided on an outer edge of a pair of side edges of each of the blades, and arranged at predetermined intervals along a longitudinal direction of the respective blades; and a plurality of smooth portions, each being provided between a pair of the notches, wherein the notches have a triangular shape and an arcuate portion is formed in a bottom portion of each of the notches, wherein in a case where a pitch of the notches is denoted as S, and a length of each of smooth portions is denoted as M, a rate M/S of the length M of the smooth portions to the pitch S of the notches is set to 0.3<M/S<0.8.