MULTIBLADE IMPELLER AND MANUFACTURING METHOD OF THE MULTIBLADE IMPELLER

PROBLEM TO BE SOLVED: To provide a multiblade impeller wherein an expensive cost is not required and variations in characteristics is small, and its manufacturing method. SOLUTION: The multiblade impeller has ring-shaped metallic reinforcing rings 1 at both ends. A large number of metallic blades 2 are provided between the reinforcing ring 1 so as to line up in a circumferential direction, and a circular platy main plate 3 is equipped to an inner peripheral portion of each blade 2. A dovetail groove 5 is provided on each reinforcing ring 1 in a circumferential direction. The large number of blades 2 having dovetail shaped projecting portions 6 structured by extruding metallic material at first ends, is installed to the dovetail groove 5 by fitting the dovetail shaped projecting portions 6 to the dove tail groove 5. The reinforcing ring is composed of an inner peripheral side ring and an outer peripheral side ring, and the blades are respectively fitted and installed to that. COPYRIGHT: (C)2004,JPO