Patent ID: 8356938

Claim:
A method for producing a fluid dynamic bearing apparatus which comprises a housing portion, a sleeve portion provided inside the housing portion, a shaft member which rotates relative to the housing portion and the sleeve portion, a radial bearing portion which rotatably supports the shaft member in the radial direction by a lubricating film of a fluid produced in a radial bearing gap between the sleeve portion and the shaft member, and an annular sealing portion positioned at least one end side of the sleeve portion, the sealing portion being provided on the shaft member, a sealing space being formed on the outer circumferential surface side of the sealing portion such that the sealing portion has a tapered face formed on an outer circumferential surface, the sealing space being formed between the tapered face and an inner circumferential surface of the housing portion, an outer diameter of the tapered face gradually decreasing toward the outside of the housing portion, the method comprising steps of: forming the tapered face of the sealing portion by machining, while simultaneously producing process-induced marks on the tapered face of the sealing portion by the machining of the tapered face, the producing process-induced marks having such a configuration that can draw the fluid inside the sealing space into the housing portion.