Patent ID: 8475053

Claim:
An inner ring, comprising: a first fit portion that extends in such a manner that a diameter of the first fit portion increases toward a first axial end of the inner ring, and that has a spring property; a first end portion that extends radially outward from a first axial end portion of the first fit portion; a first shoulder portion that extends from an outer periphery of the first end portion toward a second axial end of the inner ring, and that faces the first fit portion in a radial direction with a clearance left between the first shoulder portion and the first fit portion; a second fit portion that is formed next to the first fit portion in an axial direction, that extends in such a manner that a diameter of the second fit portion increases toward the second axial end of the inner ring, and that has a spring property; a second end portion that extends radially outward from a second axial end portion of the second fit portion; a second shoulder portion that extends from an outer periphery of the second end portion toward the first axial end of the inner ring, and that faces the second fit portion in the radial direction with a clearance left between the second shoulder portion and the second fit portion; and a raceway portion that has an arc-shaped cross section, that is contiguous to the first shoulder portion and the second shoulder portion, that has an inner ring raceway surface, and that faces the first fit portion and the second fit portion in the radial direction with a clearance left between the raceway portion and the first and second fit portions, wherein the first fit portion, the first end portion, the first shoulder portion, the second fit portion, the second end portion, the second shoulder portion and the raceway portion are monolithically formed, and the first fit portion and the second fit portion are curved in the axial direction; and wherein the first shoulder portion is substantially perpendicular to the first end portion, or the second shoulder portion is substantially perpendicular to the second end portion.