Patent ID: 8475111
Filing Date: 2013-07-02
Classification: F04D

Abstract:
1. A ring fan and shroud air guide system comprising: a fan member having a hub and a plurality of blades extending outwardly from the hub; a ring member attached to the blades, said ring member having a conical axially extending shape; a shroud member positioned around said fan member and ring member, said shroud member having a portion axially overlapping and radially inward of a first portion of said ring member and forming a tip gap with a second portion of said ring member; and said shroud member and said first portion of said ring member forming a recirculation nozzle; a plurality of guide vanes positioned in said shroud member, said guide vanes having a curved configuration to minimize the tangential component of the recirculation air flow through said tip gap; said guide vanes having a leading edge and a trailing edge, said leading edge positioned axially overlapping a first portion of said ring member.