Patent ID: 8100642

Claim:
A centrifugal blower comprising: a housing comprising a bottom wall and a sidewall surrounding the bottom wall, the sidewall defining an air outlet therein; a cover arranged on a top of the sidewall of the housing, the cover comprising a main body and a tongue extending from the main body toward the bottom wall, the tongue being flake-shaped with an even thickness and located adjacent to the air outlet, the tongue comprising a first flake, a second flake and a third flake smoothly connecting with the first and second flakes; and an impeller received in a space formed between the housing and the cover, the impeller and the sidewall cooperatively defining an air channel therebetween, the impeller comprising a hub and a plurality of blades extending outwardly from the hub, the tongue extending into the air channel and protruding toward the impeller, a distance from at least one of the first, second and third flakes to the free ends of the blades being variable along the direction from the bottom wall toward the main body.