Patent ID: 7043839

Claim:
Carried out in the manufacture of a fluid dynamic-pressure bearing unit having a shaft section including at least a shaft, and a sleeve section including at least a sleeve and a thrust bush, wherein in between the shaft section and the sleeve section a continuous oil-retaining gap including a radial bearing and/or a thrust bearing is formed, the shaft section and the sleeve section are disposed to let one rotate relative to the other with the gap intervening, and in a portion of the bearing unit in contact with air that connects the oil-retaining gap with the atmosphere a taper-seal area is formed, a method of manufacturing fluid-dynamic-pressure bearings, comprising: a first step including a substep (a) of, with the fluid-dynamic-pressure bearing unit not yet filled with oil, reducing the pressure of the environment surrounding the bearing unit to at least a predetermined pressure, and a substep (b) of injecting a first volume of oil into the taper-seal area of the bearing unit; a second step, carried out after termination of said first step, of keeping the environment surrounding the bearing unit at a pressure equal to, or pressurizing to a pressure higher than, that of the bearing unit immediately prior to said second step, then injecting a second volume of oil into the taper-seal area of the bearing unit, said second step being carried out one cycle, or a number of cycles more than that; and a pressure restoration step, carried out following termination of said second step, of restoring to atmospheric pressure the environment surrounding the bearing unit.