Patent ID: 6911753
Filing Date: 2005-06-28
Classification: F16C,H02K

Abstract:
1. A gas dynamic bearing motor comprising: a stationary shaft having a cylindrical surface; and a rotor assembly having a cylindrical portion facing the stationary shaft with a predetermined clearance interposed therebetween in a radial direction of the stationary shaft and freely rotatably fitted with the stationary shaft; a radial bearing comprising at least one of an outer circumferential surface of said stationary shaft and an inner circumferential surface of said rotor assembly having a pressure generating groove located therein; a flange-shaped disk receiving portion extending outwardly in a radial direction and located at a first end of said rotor assembly, a predetermined number of recording disks loaded on the disk receiving portion, a clamp fixed to said rotor assembly to squeeze the recording disks between the disk receiving portion and the clamp with a predetermined force for fixation of the recording; and a driving motor for rotating said rotor assembly and holding said rotor assembly and recording disks in a non-contact manner with said stationary shaft, with the action of a dynamic pressure of a gas residing in a clearance between said stationary shaft and said rotor assembly, wherein an outer diameter of said stationary shaft is constant in an axial direction thereof, while a diameter of the inner circumferential surface of said rotor assembly changes in an axial direction thereof when no recording disk is loaded on the disk receiving portion so that a clearance between the outer circumferential surface of said stationary shaft and the inner circumferential surface of said rotor assembly is substantially constant in the axial directions thereof when the recording disks are loaded on the disk receiving portion.