US 2010/0166345 A1 · FLUID DYNAMIC BEARING DEVICE

Abstract

A protrusion (7b3) directed axially downwards is provided at a bottom portion (7b) of a housing (7), and an outer peripheral surface (7b31) of the protrusion (7b3) is fixed to an inner peripheral surface (6a) of a bracket (6). When a thrust load is applied to the bottom portion (7b) of the housing (7), a part of the load is supported by the bracket (6) via the protrusion (7b3). Thus, a strength of a boundary portion (P) between a side portion (7a) and the bottom portion (7b) of the housing (7) increases, making it possible to prevent rupture of the boundary portion (P) due to an excessive thrust load. On the other hand, a wall thickness of the bottom portion (7b) can be made invariable, so it is possible to suppress deformation through molding shrinkage of a thrust bearing surface formed on an inner end surface (7b1) of the bottom portion (7b).

Claims4

Dependent claims

A fluid dynamic bearing device comprising:

a housing which has a side portion and a bottom portion integrated with each other and whose side portion has an opening at one end and is closed at another end by the bottom portion;
a shaft member accommodated in the housing;
a radial bearing gap facing an outer peripheral surface of the shaft member;
and
a thrust bearing gap facing an inner end surface of the bottom portion of the housing,
wherein the bottom portion of the housing includes an outer periphery of an outer end surface thereof a protrusion protruding axially and away from the opening, and
wherein the protrusion is fixed to an inner peripheral surface of a bracket.

4 more elements

Dependencies are inferred from the claim text.

Fluid dynamic bearing device

Life of this patent

Fluid dynamic bearing device

Life of this patent

Abstract

Claims4