Patent ID: 7832982

Claim:
A centrifugal fan comprising: a casing; and an impeller that is mounted in the casing and turns about a defined axis of rotation, the casing having an axial inlet opening, through which air is drawn in, and a tangential air discharge opening through which the air is blown out, the tangential discharge opening being delimited by a first edge that is substantially parallel with the axis of rotation and is located in the vicinity of the impeller, by a second edge opposite the first edge and spaced from the impeller and by two lateral edges, each joining the first edge to the second edge; the centrifugal fan further comprising an appendage located in the vicinity of the tangential discharge opening, delimited by the first edge and having a convex surface inside the casing and a transition surface between the convex surface and the first edge; and the centrifugal fan further comprising a protrusion, extending along each lateral edge towards the opposite lateral edge, forming a single rounded shape frame along the second edge and along the two lateral edges.