Patent ID: 7059772

Claim:
A hydrodynamic bearing in a spindle motor having a rotation axis, comprising: a shaft; a sleeve relatively rotated with respect to said shaft; a bearing portion including a micro gap formed between said shaft and said sleeve, a lubricating oil retained as a working fluid in said micro gap, and a dynamic pressure generating groove formed on at least one side of an outer peripheral surface of said shaft and an inner peripheral surface of said sleeve in said micro gap, for generating a dynamic pressure so as to support a rotation of said shaft or said sleeve; a capillary seal portion adjoining said bearing portion, the capillary seal portion comprising: a first capillary seal portion adjoining said bearing portion, and having a first radial gap between an outer surface of said shaft and an first inner peripheral surface of said sleeve, said first radial gap at least widening the further along said rotation axis the radial dimension of said gap is from said bearing portion; and a second capillary seal portion adjoining said first capillary seal portion, and having a second radial gap between an outer surface of said shaft and an second inner peripheral surface of said sleeve, said second radial gap at least widening the further along said rotation axis the radial dimension of said gap is from said bearing portion; wherein a first radial separation of the first inner peripheral surface from the rotation axis at least shortens the further along said rotation axis the first radial separation is from said bearing portion, and said first inner peripheral surface forms a first angle θ 1 , whose value is in the range a 0<θ 1 ≦90°, with respect to said rotation axis, a second radial separation of the second inner peripheral surface from the rotation axis at least shortens the further along said rotation axis the second radial separation is from said bearing position, and said second inner peripheral surface forms a second angle θ 2 , whose value is in the range 0≦θ 2 <90°, with respect to said rotation axis, and said first angle θ 1 and said second angle θ 2 have a relation θ 1 >θ 2 .