Patent ID: 9334879
Filing Date: 2016-05-10
CPC Classification: B21D,F04D,G06F,H05K,Y10T

Claim Text:
1. A method, comprising: rotating a fan; and guiding air through a plurality of perforations on a plate proximate to the fan, wherein the plurality of perforations are configured in a pattern that comprises the plurality of perforations arranged in concentric circles centered at a point, wherein each of the perforations is a closed shape comprising four edges, with rounded corners between adjacent edges, wherein two opposite edges of each of the perforations comprise non-parallel straight lines that meet at the point, and two other opposite edges comprise concentric, offset curved lines of a first radius and a second radius respectively centered at the point, wherein each perforation is sized such that the edges of each perforation are tangential to a hypothetical circle inside the perforation having a diameter equal to a difference between the first radius and the second radius.