Abstract: In order to prevent degradation of accuracy and decrease of strength when a hydrodynamic bearing device is assembled and to reduce a cost of the hydrodynamic bearing device, a guide face serving as a guide when a disc hub is press fitted into a shaft member is formed on the shaft member. Then, the guide face, an outer circumferential surface of the shaft member adjacent to the guide face, and a boundary portion between the guide face and the outer circumferential surface are ground simultaneously, thereby forming a blunting portion having a radius r in the boundary portion. Thus, no edge remains between the guide face and the outer circumferential surface. Therefore, press-fitting resistance when the disc hub is press fitted to an end of the shaft member can be reduced.

Abstract: In order to prevent degradation of accuracy and decrease of strength when a hydrodynamic bearing device is assembled and to reduce a cost of the hydrodynamic bearing device, a guide face 2c serving as a guide when a disc hub 3 is press fitted into a shaft member 2 is formed on the shaft member 2. Then, the guide face 2c, an outer circumferential surface 2a3 of the shaft member 2 adjacent to the guide face 2c, and a boundary portion between the guide face 2c and the outer circumferential surface 2a3 are ground simultaneously, thereby forming a blunting portion 2d having a radius r in the boundary portion. Thus, no edge remains between the guide face 2c and the outer circumferential surface 2a3. Therefore, press-fitting resistance when the disc hub is press fitted to an end of the shaft member 2 can be reduced.

Abstract: A rolling contact bearing assembly comprises an inner race member adapted to be mounted on a rotatable element and including a spacer disposed axially adjacent the inner race. This inner race member is formed with a lubricant reservoir for accommodating a lubricant and a lubricant flow passage communicating the reservoir with a space defined between the inner and outer race, in which space rolling elements are accommodated. At least a portion of said lubricant flow passage is defined by minute interstices which are formed by surface roughness left by surface roughening at an interface between mutual contact faces of a plurality of component parts forming the inner race member.