Patent ID: 9273692
Filing Date: 2016-03-01
CPC Classification: F04D,F05B,F05D,Y10T

Claim Text:
1. A centrifugal fan comprising: an impeller centered on a central axis extending in a vertical direction; a motor portion arranged to rotate the impeller about the central axis; and a housing arranged to contain the impeller and the motor portion; wherein the housing includes: the upper plate portion or the lower plate portion includes an air inlet; the upper plate portion, the side wall portion, and the lower plate portion are arranged to together define an air channel portion arranged to surround the impeller; one of the upper and lower plate portions and the side wall portion together define a single housing component molded by casting; a portion of the one of the upper and lower plate portions which is along a boundary between the side wall portion and the one of the upper and lower plate portions defines an increased thickness portion arranged to have an axial thickness greater than that of a remaining portion of the one of the upper and lower plate portions, the thickness of the increased thickness portion gradually increasing with increasing distance from the central axis; and an outer surface of the side wall portion includes a gate mark elongated in a circumferential direction, at least a portion of an axial range of the gate mark overlapping with an axial range of an inner surface of the increased thickness portion.