To improve the reliability and manufacture with little man-hour by fitting one end of a rotating shaft part onto a fitting hole in a flange part formed separately from the shaft part, and brazing the fitting part for integral formation.

A flange part 1 is formed into a specified shape beforehand, over which circular protrusions are formed. A fitting hole 3 is drilled at the circular protrusion part of the flange part 2, and a boss 1 is formed around the fitting hole 3. One end of the shaft part 4 formed separately at the fitting hole 3 is fitted, and the lower surface of the flange part 2, and one end of the shaft part 4 are positioned preferably so as to be flush with each other. Plating consisting of prescribed brazing is applied to the outer periphery 7 of the shaft part 4 for furnace brazing under a reducing decompression atmosphere. A part where the rotating shaft part moves to the surface 8 of the flange part 2 from the shaft part outer periphery 7 of an integrally-formed rotating shaft element 6 is machined to be formed into a curved surface 9 shape. The outer periphery 7 of the shaft part and the surface 8 of the flange part 2 are also machined to form the rotating shaft element 6.