Patent ID: 9458852
Filing Date: 2016-10-04
CPC Classification: F04D

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 accommodate the impeller; wherein the housing includes: at least one of the upper and lower plate portions 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; a boundary between an inside surface of the side wall portion and one of a lower surface of the upper plate portion and an upper surface of the lower plate portion is arranged to have a member arranged thereon, the member extending in a line along the boundary; and the member includes a flow control surface arranged to extend radially outward from the one of the lower surface of the upper plate portion and the upper surface of the lower plate portion to the inside surface of the side wall portion while becoming more distant from the one of the lower surface of the upper plate portion and the upper surface of the lower plate portion wherein the side wall portion includes: the member is arranged on a boundary between an inside surface of the first side wall portion and the one of the lower surface of the upper plate portion and the upper surface of the lower plate portion; and the first side wall portion is arranged to have a thickness smaller than that of each of the second and third side wall portions.