Patent ID: 7371010
Filing Date: 2008-05-13
Classification: F16C,H02K

Abstract:
1. A hydrodynamic bearing device comprising a sleeve having a bearing hole formed therein, and a shaft inserted in the bearing hole, one of said sleeve and said shaft being fixed and the other being made to be rotatable, wherein said shaft has a screw hole for fastening another members to the shaft, the screw hole being formed to extend from one end portion of the shaft along a direction of an axis thereof to the other end side past an opening one end portion of the sleeve, an operating fluid is charged in a gap between an inner peripheral surface of the sleeve and an outer peripheral surface of the shaft, radial bearing parts having dynamic pressure generating grooves formed therein are provided on at least one of the inner peripheral surface of the sleeve and the outer peripheral surface of the shaft, and an inside diameter of the sleeve in a predetermined range including at least an area ranging from the opening one end part of the sleeve to a tip end portion of a screw that is screwed into the screw hole is formed to be larger by an expected deformation amount in a diameter direction of the shaft than an inside diameter of the sleeve in a range on the other end side from the predetermined range.