Patent ID: 6412984
Filing Date: 2002-07-02
Classification: F16C,G11B,H02K

Abstract:
A dynamic pressure bearing apparatus comprising:a bearing member having a thrust bearing surface provided at a bottom of a cylindrical bore, a radial bearing surface provided on an inner peripheral surface portion of said cylindrical bore, and a lubricating oil reservoir provided at an opening portion of said cylindrical bore, an inner peripheral surface of said lubricating oil reservoir having a diameter greater than that of said radial bearing surface and being connected to said inner peripheral surface portion of said cylindrical bore by a substantially radial step surface; and a rotary shaft disposed within said cylindrical bore and having a radial receiving surface opposed to said radial bearing surface with the interposition of a radial bearing gap, and a thrust receiving surface opposed to said thrust bearing surface; and wherein said bearing member is closed at the bottom thereof, a dynamic pressure generating groove is formed in at least one of said radial bearing surface and said radial receiving surface, and said dynamic pressure generating groove generates a force for flowing lubricating oil between said bearing member and said rotary shaft toward said opening portion of said cylindrical bore.