Patent ID: 10626881

Abstract:
A compressor-impeller fixing nut has a tubular shape, and includes: a curved-surface shaped portion disposed in a first range from a first end side in an axial direction, the curved-surface shaped portion having an outer diameter which increases toward a second end side in the axial direction and including an outer peripheral surface having a curved shape which protrudes outward in a radial direction in a cross section along the axial direction; and a nut portion disposed in a second range closer to the second end side from the first range in the axial direction, the nut portion having an outer peripheral surface with a nut shape. An expression (D1max−D1min)/2<L is satisfied, where L is a length of the first range in the axial direction, and D1max is a maximum value and D1min is a minimum value of the outer diameter of the curved-surface shaped portion in the first range.