Patent ID: 8784060

Claim:
A centrifugal fan comprising: a circular main plate driven and rotated by a motor rotary shaft; a plurality of blades fixed to an outer circumferential portion of the main plate and spaced apart at predetermined intervals in a circumferential direction of the main plate; and a side plate attached to ends of the blades opposite to the main plate, an air inlet port being formed at a center of the side plate, the side plate inclining outward in a centrifugal direction from the air inlet port, the side plate having an arcuate cross section with a predetermined radius of curvature, wherein the centrifugal fan includes a dead water region reducing space that is formed between each of the blades and the side plate, the dead water region reducing space extending from a leading edge of each blade to a trailing edge of the blade, wherein a portion of each blade is bent in a direction opposite to a rotating direction, the blade being joined to an arcuate surface of the side plate with the bent portion, thereby forming the dead water region reducing space between the blade and the side plate, and wherein the bent portion projects in the direction opposite to the rotating direction with respect to a line, which extends from the joint portion between the blade and the main plate along an axis of the motor rotary shaft, on a plane including the axis of the motor rotary shaft.