Engine cooling fan

Claim 1

An engine cooling fan driven by an engine and located in a shroud having a cylindrical rear end and extending from a radiator to said engine, comprising: a hub having a cylindrical rear end portion for mounting said fan on said engine, a plurality of blades provided on said hub, and a ring fixedly provided on tip portions of said blades and extending in an axial direction so as to fully encircle said tip portions of said blades and forming a radial clearance between said shroud and said ring, said ring including a front end portion, a rear end portion positioned axially rearwardly of said cylindrical rear end of said shroud and extending radially outwardly of said shroud, said hub, said blades and said ring further comprise a one piece member which comprises synthetic resin and said rear end portion of said ring is rounded in shape and convex toward said engine so as to form a U-shape to effectively restrict the flow from the rear side of said fan into said radial clearance formed between said shroud and said ring, the outermost diameter portion of which is dimensionally greater than the diameter of said rear end of said shroud, said ring extending axially along an outer diameter portion of the blades from said front end portion to a radially outermost portion of said rear end portion and wherein said ring is enclosed by said shroud from said front end portion of said ring to at least a mid-portion of said ring.