International Business Machines Corporation

Holavanahally Seshachar Nagaraj

Neal Bertram Schirle

Chen-Hsiung Lee

Thomas Edward Karis

Daniel Robert Stacer

Larry Joe Gilliland

Charles Allan Brown

Herman Russell Wendt

John Martin Burns

Arthur F Diaz

Robert D Johnson

Andrew Keith Hanlon

Muhammad Inayet Ullah

M Amine Hajji

My Thanh Nguyen

Leo Volpe

James Joseph O'Neill

A bearing structure for a spindle motor is disclosed. The bearing structure provides a fluid bearing seal and support structure that may simultaneously addresses the problems of preventing oil leakage, of maintaining the bearing integrity under shock, of reducing oil evaporation and of minimizing distortion of the active bearing surface. The bearing structure includes a thrust plate coupled to a shaft and a bearing plate and load plate coupled to a sleeve, wherein the load plate urges the bearing plate towards the thrust plate, and wherein an adhesive is interposed between the load plate and the thrust plate. The adhesive may be an UV epoxy. The sleeve is operatively coupled to a stator, and the stator rotates the sleeve upon receiving a drive signal. The bearing further includes a diffusion barrier disposed between the sleeve and the stator. A second diffusion barrier is disposed between the load plate and the shaft. The bearing structure may also include an O-ring disposed above the bearing plate for sealing a gap between the bearing plate and the sleeve.

Fluid bearing seal and support structure

A hard disk drive spindle motor has a hub, a drive shaft, and a bearing therebetween. The spindle motor also has a ferrofluid seal to prevent any incidental oil emissions from the bearing from entering the drive. A ferrofluid cap is mounted on the axial end of the spindle motor for sealing the ferrofluid seal. The cap is a flat ring and has an elastomeric pad around its outer edge. The pad seats in a recess in the bore of the hub. The cap does not touch the shaft as it rotates with the hub about the shaft. Any excess ferrofluid from the ferrofluid seal is forced radially outward away from the shaft by centrifugal force. The cap contains the excess ferrofluid within the spindle motor and prevents it from entering other areas of the disk drive.

Ferrofluid cap seal for spindle motor

Improved shield designs for ball bearing based spindle motors that exhibit improved containment of grease and the base oil within the bearings at accelerated conditions of temperature and speed is disclosed. Improved shield designs are provided at the shield OD contact area, the use of an impervious shield material, the use of barrier films, shield/bearing designs that use tortuous paths and labyrinth schemes for reducing the oil and grease loss from the shield ID gap of DASD spindle ball bearings, and improved stainless steel shield designs.

Ball bearing oil/grease loss containment shield

The invention relates to a magnetic recording data storage device which can operate effectively at high rotational speeds. The magnetic recording device of the present invention comprises (a) a magnetic recording disk, (b) a spindle motor, (c) a head supported on an air bearing carrier, and (d) an actuator connected to the head carrier for moving the head across the rotating disk. The spindle motor comprises ball bearings lubricated by a grease comprising a polymeric amine and bis or tris (alkyl phenyl)phosphate. The grease improves rotational operation of the disk drive.

Magnetic recording device

Shield designs for ball bearing based spindle motors that exhibit containment of grease and the base oil within the bearings at accelerated conditions of temperature and speed are provided at the shield OD contact area, the use of an impervious shield material, the use of barrier films, shield/bearing designs that use tortuous paths and labyrinth schemes for reducing the oil and grease loss from the shield ID gap of DASD spindle ball bearings, and stainless steel shield designs.

Ball bearing oil/grease loss containment method

A method of degassing a disk drive component including heating the drive component to a temperature ranging from about 70.degree. C. to 250.degree. C.; subjecting the drive component to vacuum pressure during heating, the vacuum pressure having a first pressure and a second pressure; and monitoring the vacuum pressure to determine the level of degassing of the disk drive component.

Vacuum baking process

A magnetic recording data storage device includes a magnetic recording disk, a spindle motor, a head supported on an air bearing carrier and an actuator connected to the head carrier for moving the head across the rotating disk. The spindle motor has lubricant covered ball bearings where the lubricant includes an alkali hydroxystearate, an ester oil, a dialkyldiphenylamine and a dialkyldithiocarbamate.

Magnetic recording device with spindle motor lubricant of specified

A vent is disclosed for a screw mounted support shaft of a fluid dynamic bearing for a spindle of a magnetic disk file. The support shaft for mounting a spindle bushing has an axial hollow center internally threaded at one end, and has upper and lower bearing journals for rotatably mounting the spindle bushing with a fluid lubricant. The bearing journals are separated by a recess having a vent passage between the recess and hollow center. A screw is threaded through the base plate or cover into the threaded end of the support shaft, mounting the support shaft to the base plate or cover. An air vent passage, such as a slit is provided axially either in the threaded end of the hollow center of the support shaft or in the screw, and radially across the end of the support shaft so the air bleed passage extends from the hollow center externally of the support shaft.

Fluid spindle bearing vent

An improved disk drive system using a non-ferrofluid conductive lubricant is disclosed. In the disk drive system, there is a plurality of critically spaced magnetic disks rotated by a disk motor. A spindle shaft, which is retained by the spindle sleeve, couples to the disk motor and to the plurality of magnetic disks for rotation. The spindle shaft and spindle sleeve uses a bearing, which is lubricated by a non-ferrofluid conductive lubricant. The lubricant is used to prevent electrostatic charge build up during operation of the disk drive system. The lubricant may be either a non-polar oil or a ball bearing grease and further having either a metal caged fullerenes compound, STADIS-450, ASA-3, or Polyfloe 130. One particular type of lubricant is an emeraldine salt of polyanilin produced according to the steps of first reacting a solution of HCL and ammonium persulfate into a solution of HCL and analine to form a polymer. Next, the polymer is mixed with ammonium hydroxide and then is prepared to have a molecular weight of 1,000-20,000. Finally, the polymer is mixed with dodecyl benzylsulfonc acid or camphor sulfonic acid until the emeraldine salt is formed.

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Morgan Hill, CA, United States of America

Holavanahally Seshachar Nagaraj