Seagate Technology Incorporated

Other

Nidec Corporation

Jeffry Arnold LeBlanc

Troy Michael Herndon

Robert Alan Nottingham

Norbert Steven Parsoneault

Alan Lyndon Grantz

Paco Gregor Flores

Anthony Joseph Aiello

Robert Michael Pelstring

Michael David Kennedy

Christopher Michael Woldemar

Jerry Joseph Weingord

Thaveesinn Vasavakul

James Scott Bowdoin

Hans L Leuthold

Klaus Dieter Kloeppel

Raquib Uddin Khan

Junya Mizukami

Mohamed Mizanur Rahman

Alan Lydon Grantz

Takuro Iguchi

Mohammad Mahbubul Ameen

Donald James Macleod

Alexander Gredinberg

Michael Ray Tiller

Lynn B Le

James Ian Lee

Hiroki Yamada

Tetsuya Maruyama

James Sidney Lee

Alexander Parkhomovsky

Tsuyoshi Morita

Marten Fredrick Byl

Saul Ceballos

Gregor Flores

Tan Hung Pham

Michael James Whittome

Norbert Steve Parsoneault

Robert Alan Notthingham

Robert Alan Notingham

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 rotating hub and fixed spindle assembly with first and second fluid dynamic journal bearings and first and second fluid dynamic thrust bearings for a disc drive memory system has a pump seal and a radial ring seal at a first axial terminus for lubricant containment, and a capillary seal and a labyrinth seal at a second axial terminus for lubricant containment and storage. Lubricant fluid pressure differences between first and second seals are minimized through one or more lubricant fluid communicating channels in the hub assembly, in order to minimize lubricant fluid loss through a seal. Lubricant fluid can also be purged of any air bubbles by lubricant fluid circulation through the channel.

Hub and spindle assembly

A fluid dynamic bearing apparatus includes a first minute gap, a second minute gap, a third minute gap, a fourth minute gap, and a fifth minute gap. A flow of a lubricating oil from the fifth minute gap to the fourth minute gap is caused by a plurality of dynamic pressure generating grooves arranged within the fluid dynamic bearing apparatus. This flow causes air bubbles mixed in the lubricating oil within the fifth minute gap to flow toward the third minute gap and be discharged to an outside through the third minute gap. In addition, a flow of the lubricating oil into the third minute gap caused by a centrifugal force accompanying rotation is inhibited.

Fluid dynamic bearing apparatus arranged to discharge air bubbles generated therein and a spindle motor and a disk drive apparatus including the same

According to various embodiments of the invention, a motor with a rotatable hub having fluid dynamic journal and thrust bearings can be assembled from four major components: a spindle, a hub, a thrust washer, and a base. The spindle can integrate journal bearing, axial limiter, and ring seal functions. The hub can integrate journal bearing, thrust bearing, ring seal, axial limiter, capillary seal, and bumper functions. The thrust washer can integrate thrust bearing and lubricant circulation functions. The base can integrate capillary seal and lubricant storage and circulation functions. Each function can be integrated as structural feature in its corresponding component. The spindle, hub, and thrust bearing can be preassembled. The base can be loaded with lubricant prior to assembly with the spindle/hub/thrust bearing combination.

Spindle regions

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

Multifunctional components enable the construction of economical motor assemblies. A first embodiment of the present invention provides a hub, cup, spindle, and base assembly for a motor assembly having at least one journal bearing, at least one thrust bearing, and at least one fluid seal. A second embodiment of the present invention provides a hub, spindle, and base with integrated cup assembly for a disc drive bearing having at least one journal bearing, at least one thrust bearing, and at least one fluid seal. In a third embodiment, a hub is rotatably assembled with a spindle coupled to a thrust bearing, prior to assembly with a base. In further embodiments, motor assemblies comprise the above embodiments combined with stator and rotor assemblies.

Motor assembly with multifunctional components

A fluid dynamic bearing having a hub, a sleeve, and a sealing arrangement comprising a first capillary seal substantially retaining a first fluid and a second capillary seal comprising a second fluid. The second capillary seal is located between the first capillary seal and an opening between the hub and the sleeve.

Dual seal for optimized performance

A method of designing an improved bearing system is provided. In one embodiment, the method for designing a fluid dynamic bearing system includes determining a first stability ratio for a first journal bearing configuration. The method further includes determining a second stability ratio for a second journal bearing configuration. In one embodiment, the first configuration has two sub-journal bearings and the second configuration has three sub-journal bearings. The two stability ratios may then be compared to determine whether adding a sub-journal increases the stability ratio of the bearing system.

Method for designing a fluid dynamic bearing system

A fluid dynamic bearing motor including a stationary sleeve, a rotating shaft axially disposed through the sleeve, a journal gap between the shaft and the sleeve, the gap defined by first and second interfacial surfaces of the shaft and sleeve, at least one set of fluid dynamic grooves formed on the first interfacial surface of the journal gap, and at least one step defined on the second interfacial surface of the journal gap.

Hydraulic compensation for magnetically biased fluid dynamic bearing motor

For motors having a journal with one or more groove regions and a shaft for relative rotation in the journal, aspects include providing a dual tapered shaft. The shaft may be tapered by the application of a wear resistant coating at least opposite the groove regions. The coating introduces a shaft taper from near a top end and from near a bottom end towards the shaft middle. The shaft taper may provide for improved pumping efficiency. The coating may be applied in various processes such as chemical vapor deposition or physical vapor deposition to establish a thickness gradient of coating material from near the top end and near the bottom end towards the shaft middle. In one example, the coating includes a DLC coating. Additionally, shaft portions may be shielded to prevent coatings thereon.

FDB motor with tapered shaft for improved pumping efficiency

In one example, a FDB motor having a top-cover attached, EM biased bearing system is provided. The motor includes a shaft and rotor disposed for relative rotation, and an axial limiter for restricting axial movement of the rotor with respect to the shaft, wherein the axial limiter is wet or lubricated during contact. The limiter is spatially fixed with respect to one of the shaft or the rotor and disposed with an axial end surface opposing a surface portion spatially fixed with respect to the other of the shaft or the rotor to form a gap therebetween. The gap may be filled with a fluid such as bearing lubricant, thereby providing a lubricated or wet contact surface to restrict axial movement of the shaft and rotor. Additionally, one or both surfaces may include a groove or slot to provide circulation of fluid through the gap.

Lubricated limiter for fluid dynamic bearing motor

An improved rotational motor, such as a spindle motor for a disc drive, is provided. The motor first comprises a hub having a shaft portion and a horizontal body portion. The motor also comprises a sleeve surrounding the shaft portion of the hub. A fine first vertical gap is retained between the shaft and the inner diameter of the surrounding sleeve. In addition, a fine horizontal gap is provided between the upper hub portion and the top of the sleeve. A third gap is preferably provided between the hub and an outer diameter of the sleeve. The first vertical gap is filled with a lubricating liquid, such as a clean oil. A capillary seal is provided in the third gap. In one embodiment, the lubricating liquid extends into the horizontal gap. Oil pumping grooves are machined along the horizontal fluid gap. When the hub is rotated, the oil pumping grooves impel oil towards the shaft. This prevents any portion of the first vertical gap from becoming un-lubricated during rotation of the shaft.

Radial pumping oil seal for fluid dynamic bearing motor

A fluid bearing design is provided which according to one aspect includes a shaft defining together with a surrounding sleeve an asymmetric journal bearing, and a thrust bearing at or near an end of the shaft towards which the asymmetric journal bearing is pumping, with that end of the shaft being closed off. The journal bearing asymmetry establishes a hydraulic pressure toward the closed end of the shaft. This pressure provides an axial thrust to set the bearing gap for the conical bearing. The conical bearing itself is a relatively balanced bearing, although it may have a bias pumping toward the shaft and the journal bearing. A pressure closed equalization path from the journal bearing through the conical bearing to the end of the shaft may be established to maintain a constant hydraulic force across the conical bearing, and which may also prevent any asymmetry in the conical bearing from affecting the net thrust force acting upon the end of the shaft where the conical bearing is located. Alternatively, in a fluid dynamic bearing design comprising a shaft and a thrust plate at or near an end of the shaft, asymmetry is again established along the journal bearing to establish a pressure gradient directed toward the thrust bearing.

Hydraulic fluid dynamic bearing incorporating an asymmetric journal bearing

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Aptos, CA, United States of America

Jeffry Arnold LeBlanc