A centrifugal blower has a frusto-conical end wall with a central hub and a plurality of elongated blades disposed parallel with the hub axis and carried around the outer periphery of the end wall. A continuous ring is connected to the distal ends of the blades with portions of the blades projecting both radially inwardly and outwardly of the ring. End edge portions of the blades adjacent to the end wall project radially outwardly beyond the periphery of the end wall and are both tapered backwardly in the opposite axial direction and beveled.

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