Patent ID: 8240989
Filing Date: 2012-08-14
Classification: F04D

Abstract:
1. A fan, comprising: a fan frame comprising a main body and a base, wherein the main body has a column-shaped passage, an outlet and an inlet, and the base is disposed in the main body and is adjacent to the outlet; and an impeller accommodated in the main body and disposed on the base, wherein the impeller has a hub and a plurality of blades disposed around the hub; wherein the diameter of the hub increases gradually from the inlet to the outlet so as to form at least one slant plane, the base has an inclined plane corresponding to the slant plane of the hub, and the slant plane of the hub and the inclined plane of the base are roughly located at the same plane, wherein the main body has a first expansion portion disposed adjacent to the outlet, the first expansion portion stretches outwardly and extends from the column-shaped passage to the outlet, the main body further has at least two planar sides so as to allow parts of the first expansion portion to respectively form a straight-cut line where each planar side is located, the base has at least two straight-cut planes, and each of the straight-cut planes is located coaxially to the straight-cut line of the first expansion portion, and the straight-cut line and the straight-cut planes are substantially perpendicular to a surface of the outlet.