Patent attributes
A centrifugal fan includes: a casing having an upper casing with an air suction opening, a lower casing, and a plurality of support members disposed between the lower casing and the upper casing with air discharge openings provided between the support members; an impeller disposed between the upper and lower casings, and including an annular upper shroud provided on an upper casing side, a base plate integrally formed with the annular upper shroud, and a plurality of blades arranged along a circumferential direction between the annular upper shroud and the base plate; and a fan motor which rotates the impeller. A plurality of recesses are provided on the upper surface of the upper casing, and formed to surround the air suction opening, and a plurality of ribs are radially provided around the air suction opening and between the adjacent recesses.
