Patent ID: 7384241

Claim:
A fan with ring comprising: a cylindrical ring portion having a generally cylindrical outer face, said cylindrical outer face having a first end and a second end; and a plurality of blade portions located within the ring portion and projected radially from a boss portion, wherein the fan with ring comprises connection portions constituted by connecting in one piece part of a front end edge of each of the blade portions with part of an edge of the ring portion, the blade portions, the ring portion, and the boss portion are molded in one piece from a press-molded form of a single metal plate, a blade surface of each of the blade portions has a sloped plane twisted relative to a plane of the boss portion, the connection portions at the front ends of the blade portions are formed in one piece such that sloped concave portions, that are diagonally depressed, with edges included in the ring portion, are flush with the sloped planes, said first end of said cylindrical outer face comprises outer peripheral arcuate segments, said edges of said sloped concave portions which are included in the ring portion are continuous with said arcuate segments, said edges of said sloped concave portions extending away from said first end of said cylindrical outer face towards said second end of said cylindrical outer face, said edges of said sloped concave portions converging from respective said arcuate segments towards said second end of said cylindrical outer face.