International Business Machines Corporation

Hitachi Global Storage Technologies Netherlands B.v.

Thomas A Gregory

Christopher Guild Keller

Donald Ray Gillis

Norbert A Feliss

Sylvia Lui Lee

John Beck

Thomas S Larson

Charles Allan Brown

James Aloysius Hagan

Herman Russell Wendt

Vedantham Raman

James M Severson

Andrew Ching Tam

Arthur R Zingher

Peter Michael Baumgart

Thao Anh Nguyen

Karl Arthur Flechsig

Robert Waltman

Timothy Martin Reith

Todd Phillip Fracek

Run-Han Wang

Wayne J Rothschild

Leo Volpe

Owen R Melroy

Ajay Johary

James J Mayerle

Nigel F Misso

Bruce E Kennedy

Bruce A Murray

Ulla Vasant Nayak

Michael Luis Ramirez

Ronald G Lecander

A method for detecting leakage from a disk drive enclosure includes providing a lubricating composition having a lubricating material and a tag material therein. The tag material has a volatility characteristic that is amenable to analysis. The method includes measuring a concentration of the tag material in the vapor phase. By measuring a concentration of the tag material, a leak rate of the lubricating material can be determined. The lubricating composition may include a perfluoropolyether lubricating material and a halogenated sulfur tag material such as SFand/or SF.

Leak detection system of hard disk drives with lubricant reservoir

A data storage system is described with a system for controlling the amount of lubricant being dispensed from the reservoir using a feedback loop that includes at least one sensor output for a physical parameter inside device such as temperature, humidity and fly-height. In one embodiment the lubricant reservoir housing is equipped with a movable shutter over an aperture in the lubricant reservoir housing. The area of the aperture through which the lubricant vapor can pass is controlled by moving the shutter. In another embodiment the lubricant reservoir housing is supplied with a lubricant diffusion packet such as an effusion cell or diffusion tube containing liquid lubricant. An energy source for the lubricant diffusion packet allows the temperature of the lubricant and, therefore, its vapor pressure, to be increased when the need for additional lubricant is sensed. In a preferred embodiment the output from a Quartz Crystal Microbalance (QCM) with an overcoat similar to that used on a disk is used to measure the degree of lubricant saturation inside the drive by sensing the change in the frequency of a crystal oscillator due to the lubricant adsorbing on a surface of the QCM.

Closed loop lubrication system for moving magnetic media

A lubricating perfluoropolyether (PFPE) composition for lubricating one or more disks in a disk drive system may be formed by providing a first component of PFPE molecules having an aggregate vapor pressure in the range of 1&times;10 to 1&times;10 atm and a second component of PFPE molecules comprising at least 5% of the total number of molecules of the first component, wherein the second component includes an aggregate vapor pressure lower than that of the first component. The first and second components are mixed together to form a homogeneous composition, which may be in the liquid form. The composition may be introduced into a reservoir in a vapor phase lubricant reservoir system in a disk drive enclosure.

Disk drive lubricant reservoir systems and lubricants used therein

A device for monitoring lubricant within a disk drive includes a reservoir packet impregnated with lubricant. The reservoir packet is disposed between a first metal screen and a second metal screen such that a lubricant reservoir transducer is created. The capacitance of the lubricant reservoir packet is monitored and when it falls below a predetermined percentage of the initial capacitance, a user is warned to back up the files contained in the disk drive before failure due to lack of lubricant occurs.

Device and method for monitoring lubricant within a disk drive

The present invention is a magnetic disk drive for reading or writing magnetically, comprising: (i) a base plate; (ii) one or more of magnetic disks; (iii) a hub fixedly attached to the disks for supporting the disks; (iv) a motor operable to rotate the hub; (v) one or more of magnetic read/write heads, each associated with the surface of a disk; (vi) an actuator for supporting the heads and moving the heads across the disks; (vii) a support shaft attached to the base plate; and (viii) a load/unload structure for displacing the heads from the disk comprising an elongated body, a base portion fixedly attached to the base plate and a plurality of ramps extending outwardly from the body. The body of the structure is mounted through one or more holes in the body onto the support shaft so that the support shaft extends along the length of the body to support the structure.

Magnetic disk drive with load/unload structure having lubricant reservoir

A disk drive having a disk with a contact start/stop (CSS) region on which a slider can rest is described. The CSS region is divided into at least three zones with the inner and outer zones having a surface topography which is different from the surface topography of the middle zone. The middle zone of the CSS region may be textured with bumps having a lower average height, a lower average density and/or a different bump diameter. The middle zone may also be left untextured. The slider is maintained over the CSS region during spin up and/or spin down.

Disk drive with textured slider contact region

A bearing seal assembly for an oscillating actuator, comprises an outer bearing raceway, an inner bearing raceway mounted concentric with the outer raceway, and an annular deformable liquid impermeable membrane having an axial length of not more than one tenth the radius thereof, an inner peripheral edge sealingly secured to the inner bearing raceway, and an outer peripheral edge sealingly secured to the outer raceway for enabling limited relative rotation between the inner raceway and the outer raceway with minimum axial distortion of said membrane. In one embodiment, the membrane is stretched to eliminate surface distortion under torsional stress. Another embodiment illustrates waves molded into the membrane for reducing torsional forces.

Membrane seal secured to inner and outer oscillating bearing members for

A rotating magnetic storage device is shown wherein the transducer and media are separated during operation by a thin film of low viscosity liquid lubricant that is recirculated from a reservoir within the head-media enclosure. Lubricant recirculation can be effected by capillary action using a wick, mechanical pumping and metering or distillation techniques. As compared to devices using air bearing separation, the transducer carrying slider has very small bearing surfaces which may be in the form of narrow rails or small depending foot elements. This enables fly heights. of 2 microinches using a film of one micron thickness.

Apparatus and method for near contact magnetic recording

A rotating magnetic storage device is shown wherein the transducer and media are separated during operation by a thin film of low viscosity liquid lubricant that is recirculated from a reservoir within the head-media enclosure. Lubricant recirculation can be effected by capillary action using a wick, mechanical pumping and metering or distillation techniques. As compared to devices using air bearing separation, the transducer carrying slider has very small bearing surfaces which may be in the form of narrow rails or small depending foot elements. This enables fly heights of 2 microinches using a film of one micron thickness.

Near contact magnetic recording using a liquid lubricant bearing to

Method, with structure, of production of precision head/disk interfaces for near contact recording in a low viscosity liquid lubricant film. Triangular shaped bearing pads in an assembled hard drive are brought to bear upon a rotating lubricated disk to dislodge, smooth and polish any residing asperity. The triangular shape of the bearing pads sweeps away and directs to the outer edge of the disk any of the remaining fine carbon sputtering debris which is loosened as the bearing pads are drawn from the inner dimension to the outer dimension of the disk.

Magnetic slider design for precision wear-in

The back edge of a disk drive slider is used to remove debris from disk media by slowly sweeping it from the inner diameter of the disk to the outer diameter of the disk while the disk is rotating backwards from normal. The sweeping operation is completed while the disks are still gaining rotational speed so that liftoff velocity is not achieved. Material accumulated on the back edge of the slider is either dumped at the outer diameter of the disk, or remains on the back edge of the slider as normal operation is commenced.

Method and apparatus for cleaning disks upon reaching a disk drive

The lubricant film for a near contact magnetic recording device is maintained by a closed loop servo control for a recirculating lubricant supply system. A reservoir closely overlies the disk data surface and includes a heater for controlling the temperature difference between the reservoir and the disk surface. Decreasing the heater current reduces the film thickness and increasing the heater current increases the film thickness. A wick system gathers lubricant from within the disk enclosure, which may have been spun off the disk or condensed from the lubricant laden atmosphere and returns the lubricant by capillary action to the reservoir. Further, the reservoir includes two portions which are independently controllable. The first overlies the data band of the disk and the second overlies the start/stop zone and the head when the latter is not operational and parked at the nonoperating location. The start/stop zone reservoir can be used to increase the localized film thickness when the head is coming to rest on the disk surface and during start-up to prevent wear between head and disk.

Servo controlled lubricant thickness for near magnetic recording

Seal for bearings in small angle oscillation applications

An integrated head-suspension-wick system having lubrication, including a bearing area at one end that holds a magnetic transducer against the disk. The invention provides wicking grooves in the integrated head-suspension-wick arm. The grooves are shaped to cause capillary forces to pull the lubricant from the supply wick on the arm, along the suspension of the bearing area. This ensures that the disk area under the head will not go dry regardless of storage duration or conditions. When the disk is running, the wick continues to conduct lubricant to the disk surface.

Growing community of inventors

Rochester, MN, United States of America

Thomas A Gregory