AXIAL BLOWER

PURPOSE:To improve performance by forming an opening on the upper stream side of an air separator, where flow straightening vanes are arranged in alignment in a protruding part, on the upper stream side of an inlet guide vane part or in a casing part corresponding to a portion ranging from the front half part of the inlet guide vane to the upper stream side thereof. CONSTITUTION:A circular ring 36 is extended to the upper stream side of the front edge of a moving vane 32 so that an opening 38 on the upper stream side is positioned on the upper stream side of an inlet guide vane 31. A plurality of moving vanes 32 mounted peripherally of a rotary hub 43 secured on a rotary shaft 42 are arranged on the downstream of the inlet guide vane 31. A front cylinder 44 is located on the inner peripheral side of the inlet guide vane 31. Stall fluid generated to the tip part of the moving vane 32 is pushed in a moving vane tip opening 37 with whirl in the same direction as that of the moving vane 32 during running of an axial-flow blower. A recirculation flow 39 from which whirl is removed by a flow straightening vane 35 and which is restored to an axial direction is returned to a main flow part through the opening 38 on the upper stream side, and is smoothly joined with an axial flow 45 of a main flow part. This constitution delays a stall and provides an axial blower having a wide range of operation.