Dynamic pressure gas bearing motor

Abstract

A gas dynamic bearing motor is provided that is capable of setting a bearing radius to a large value to obtain a sufficient radial stiffness, and preventing lock of the bearing and scattering of wear powder outside the bearing. An annular groove 11 is provided on a lower end surface 87 of a hub 3 to thereby enable a deformation of an inner circumferential surface 82 of the hub 3 when recording disks 9 are loaded on the hub 3 to be suppressed to a small value, thereby enabling partial contact in the radial bearing to be suppressed and lock of the bearing to be prevented. Further, a protrusion 12 is provided on a base 7 in a circumferential direction and fitted in the annular groove 11 to construct a labyrinth seal, thereby enabling scattering of wear powder generated on bearing surfaces outside the bearing to be prevented.

Description

technical field [0001] The present invention relates to a dynamic pressure gas bearing used in a small spindle motor such as a hard disk device. Background technique [0002] Conventionally, with the increase in density and high-speed data transfer of hard disk devices, high-precision and high-speed rotation are strongly required for the spindle motor used. In recent years, hydraulic oil bearing motors have been increasingly used as a technology to meet this demand. Research is also being carried out on a dynamic pressure gas bearing motor that can rotate at a higher speed and is free from oil scattering and oil deterioration. [0003] Since gas has a lower viscosity than oil and is a compressive fluid, the load capacity of the dynamic pressure gas bearing per bearing unit area is low. Compared with the dynamic pressure oil bearing, it must be made larger. If the small motor used in the spindle of the hard disk device It is difficult to obtain sufficient bearing rigidity w...

AI Technical Summary

Problems solved by technology

[0013] In order to solve the above-mentioned problems, an object of the present invention is to provide a dynamic pressure gas bearing motor in which the diameter of the radial bearing is set to be large in order to obtain sufficient rigidity of the radial bearing, even if the wall thickness of the rotating body is changed. In the thin case, the deformation of the inner peripheral surface of the rotating body when the recording disk is mounted on the rotating body can also be suppressed to be small, and the partial contact at the lower end of the inner peripheral surface of the rotating body can be suppressed, and the Prevent scratch wear and bearing locking, and prevent the wear powder caused by the wear of the bearing surface from flying from the gap between the base and the lower end surface of the hub to the outside of the motor

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