Patent ID: 7866047

Claim:
A method of manufacturing a sleeve unit defined by a sleeve arranged to receive a shaft of a motor including a bearing mechanism employing hydrodynamic pressure, and of a sleeve housing that fastens to the outer periphery of the sleeve, the method comprising: a) a step of retaining a sleeve shaped essentially in the form of a cylinder centering on a center axis, and having on a first endface of the sleeve along the center axis a first hydrodynamic bearing surface; b) a step of retaining, with the center axis as center, an essentially cylindrical sleeve housing with a second endface of the sleeve housing along the center axis being opposed to a third endface of the sleeve along the center axis, the sleeve housing having on a fourth endface thereof along the center axis a second hydrodynamic bearing surface; c) a step of shifting, along the center axis, the sleeve relative to the sleeve housing to insert the sleeve into the sleeve housing, and making the center-axis-oriented separation between the first hydrodynamic bearing surface and the second hydrodynamic bearing surface be a predetermined distance; d) a step, either performed simultaneously with or after said step c), of fixing the sleeve to the sleeve housing; and wherein in said step c): the first hydrodynamic bearing surface is abutted on a first abutment surface of a sleeve retainer that retains the sleeve, and is urged in the direction toward the first abutment surface; the second hydrodynamic bearing surface is abutted on a second abutment surface of a sleeve-housing retainer that retains the sleeve housing, and is urged in the direction toward the second abutment surface; and the center-axis-oriented separation between the first hydrodynamic bearing surface and the second hydrodynamic bearing surface is made to be the predetermined distance.