Seagate Technology Incorporated

Christopher Michael Woldemar

Norbert Steven Parsoneault

Troy Michael Herndon

Anthony Joseph Aiello

Alan Lydon Grantz

Robert Alan Nottingham

Jeffry Arnold LeBlanc

Jerry Joseph Weingord

Thaveesinn Vasavakul

James Scott Bowdoin

Lynn Bich-Quy Le

Enoch Mylabathula

James Ian Lee

James Sidney Lee

Jose L Cordova

Provided herein is an apparatus, including a stationary component; a rotatable component; a fluid dynamic bearing defined by the stationary component and the rotatable component; a first channel substantially parallel to the fluid dynamic bearing; a second channel substantially perpendicular to the first channel; and a fluid reservoir substantially parallel to the first channel, wherein the second channel fluidly connects the fluid reservoir to the first channel.

Motor including reservoir and hub cap

In one example, an FDB motor having a shield member is provided. In one example, the method includes disposing a first member and a second member for relative rotation about an axis of rotation. An annular shield member is attached to the first member, the shield member disposed adjacent a fluid reservoir for containing a bearing fluid. The reservoir is filled through an aperture (e.g., a fill hole) in the shield member. Thereafter, the aperture is at least partially sealed. The aperture may be hermetically sealed via one or more laser pulses. In other examples, a two piece shield is provided for shielding a reservoir without a fill hole.

Shield restricting axial movement

A robust spindle motor is provided having improved shock resistance for fluid containment, as well as enhanced air purging characteristics. In an aspect, axial displacement of relatively rotating components is restricted by utilizing a limiter situated adjacent to a limiter bushing forming an axial limiter gap therebetween. A fluid channel, at least partially diverging, extends from a hydrodynamic bearing to the axial limiter gap, and continues to a region beyond the axial limiter gap. In an aspect, an axially diverging slot is situated adjacent to the axial limiter gap. Power is reduced by reducing viscous drag between relatively rotating components, hydrodynamic bearing length is increased, and higher stiffness of the hydrodynamic bearing is provided. Fluid volume may be increased, thereby offsetting fluid evaporation losses and allowing for the use of lower viscosity lubricants.

Air purging for a fluid dynamic bearing

In one example, a fluid dynamic bearing motor having a shield member is provided. In one example, the method includes disposing a first member and a second member for relative rotation about an axis of rotation. An annular shield member is attached to the first member, the shield member disposed adjacent a fluid reservoir for containing a bearing fluid. The reservoir is filled through an aperture (e.g., a fill hole) in the shield member. Thereafter, the aperture is at least partially sealed. The aperture may be hermetically sealed via one or more laser pulses. In other examples, a two piece shield is provided for shielding a reservoir without a fill hole.

Shielding fluid reservoirs of fluid dynamic bearing motors

In one aspect, a fluid dynamic bearing system is provided. The system may include a first member and a second member disposed for relative rotation about an axis of rotation and having opposing substantially planar surfaces defining an axial gap. A bearing region is disposed circumferentially around the axis of rotation and a relatively large gap region is disposed circumferentially around the bearing region, the large gap region having an average gap distance greater than the bearing region. The large gap region further includes at least one support pad forming a localized narrow gap distance in the axial gap to provide support between the opposed surfaces at a radial distance greater than the bearing region. For example, the support pad may support the surfaces against an externally applied force or moment that may tilt one member relative to the other.

Low power support pads for moment loading and associated methods

A spindle motor is provided comprising a fixed shaft capable of being fastened at either end to the base and cover of the disc drive. The hub which rotates around the disc drive is supported for rotation by a journal bearing and thrust bearing, with the thrust bearing grooved surfaces being defined in gaps immediately adjacent the ends of the journal bearing. A fluid recirculation path is provided through the rotating sleeve connecting the surfaces adjacent the thrust bearings, with the asymmetry which provides the fluid circulation either being inherently present due to tolerances in the bearing and groove design, or specifically provided by asymmetry in the bearing groove pattern. An asymmetric sealing system employs a pumping seal adjacent a radial end of the thrust plate near the base of the housing, and a shorter pumping seal defined adjacent a radial end of the thrust plate distal from the base.

Spool bearing with asymmetric sealing

An inboard thrust surface is provided for a spindle motor that maintains fluid flow through a journal bearing and generates an added offset pressure to avoid any subambient pressure within a journal. In an aspect, journal bearing asymmetry is minimized or eliminated and axial span is increased between journal bearings, reducing wobble or run-out between relatively rotating components. In another aspect, journal axial length is decreased for low profile disc drive memory systems and other spindle motors. In an aspect, two separate thrust surfaces provide an axial force in the same direction, opposing an axial bias force created by interaction of a stator and a magnet, and minimizing power consumption.

Inboard thrust surface fluid recirculation pump

The fluid dynamic bearings system of the invention provides a device located in a non-grooved low pressure region located at some point in the overall fluid circulation path of the fluid dynamic bearing to collect and trap any air bubbles which may be found in the fluid of the hydrodynamic bearing. More specifically, the air extraction device of the invention comprises a shallow angle V-shaped region which is located in fluid communication with but not in a grooved region of the hydrodynamic bearing. In summary, according to the present invention the hydrodynamic bearing comprises a shaft with a thrust plate at or near at least one end thereof. The thrust bearings are formed on the upper and lower surfaces of the thrust plate () and journal bearing () on the shaft or facing sleeve surface. Lubricant lies between each of these surfaces and facing surface of a sleeve () or counter-plate () which overlies the thrust bearing, and fluid lies in all these regions. In the region on the outer surface of the counter-plate distant from the shaft () and facing the counter-plate () a countersink () is formed on the axial face of the thrust plate () and end of bearing shaft with a shallow angle such that the force of surface tension forms a meniscus between the air and the lubricant along the surface of the countersink angle period. Lubricant circulation path-holes () are provided from, this countersink region to the region at the junction between the shaft and the thrust plate which also between the journal bearing and the thrust bearing. Thus the fluid can pass through these circulation holes extending from the journal and thrust plate up to the countersink region, and form a capillary seal on either side of the countersink region adjacent the thrust bearing. As an alternative, the shallow angled region may also be located on the outer diameter of the thrust plate or on the shaft adjacent the journal bearing.

Fluid dynamic bearing lubricant air extraction device

A noise damping system for a disc drive wherein the cover of the disc drive can be made or stamped out of a stainless steel constrained layer of viscoelastic damping material. The material of the cover consists of two layers of stainless steel with a thin layer of damping material sandwiched between. A foam material between the base section of the housing and the printed circuit board located below the housing avoid transmission of vibrations which would in turn generate noise.

Growing community of inventors

Santa Cruz, CA, United States of America

Christopher Michael Woldemar