CENTRIFUGAL FAN

PROBLEM TO BE SOLVED: To provide a centrifugal fan capable of preventing occurrence of rotating stall. SOLUTION: In the centrifugal fan 10 in which a rotating shaft 8 of an impeller 3 is provided to the inside of an inlet box 2, a guide member 31 is provided to the inside of the inlet box so as to come into contact in a rotating direction of rotating flow in the inlet box. A flow in the inlet box becomes a rotating flow 90 taking the rotating shaft as a center. By so doing, the rotating flow velocity of the rotating flow is enhanced to reduce the flow rate at rotating stall start. The guide member is allowed to become a guide vane. A distance between the guide member and the rotating shaft is set to be approximately equated with the distance between the rotating shaft and tilted surfaces 2d, 2e or a bottom 2c with which the rotating flow in the inlet box comes into contact. The guide member 32 is provided so as to be freely movable. COPYRIGHT: (C)2005,JPO&NCIPI