MULTI-BLADE IMPELLER MANUFACTURING METHOD

PROBLEM TO BE SOLVED: To provide a multi-blade impeller manufacturing method saving a cost, providing less variation in property, and being suited to a multi-blade impeller with a large blade diameter. SOLUTION: The multi-blade impeller has metallic and ring-shaped reinforcing rings 1 on both ends, lays a large number of metallic blades 2 side by side in a circumferential direction between the reinforcing rings 1, and is equipped with a circular plate-shaped main plate having a boss portion along an inner peripheral portion of each blade 2. So as to manufacture the multi-blade impeller, the plurality of the blades 2 are independently formed as a separated body, and the blades 2 formed as the separated body are set in a die casting mold 5 capable of molding the two reinforcing rings 1. The blades 2 and the reinforcing rings 1 are made to be an integral structure by die-cast molding, and then the circular plate-shaped main plate 3 is attached to the inner peripheral portions of the blades 2. Or, the plurality of the blades 2 are independently formed as a separated body, and the blades 2 formed as the separated body are set in a die casting mold capable of molding the two reinforcing rings and the main plate. The blades, the reinforcing rings, and the main plate are made to be an integral structure by die-cast molding. COPYRIGHT: (C)2004,JPO