Patents by Inventor Harold J. Hamilton

Harold J. Hamilton has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7095585
    Abstract: An information storage system includes a transducer having a loop of ferromagnetic material with pole tips separated by an nonferromagnetic gap located adjacent to a medium such as a rigid disk. During writing the separation between the pole tips and the media layer of the disk is a small fraction of the gap separation. Due to the small separation between the pole tips and the media layer, the magnetic field generated by the transducer and felt by the media has a larger perpendicular than longitudinal component, favoring perpendicular recording over longitudinal recording. The media may have an easy axis of magnetization oriented substantially along the perpendicular direction, so that perpendicular data storage is energetically favored. The transducer may also include a magnetoresistive sensor for reading magnetic information from the disk.
    Type: Grant
    Filed: October 20, 2004
    Date of Patent: August 22, 2006
    Assignee: Seagate Technology LLC
    Inventors: Alexander P. Payne, William C. Cain, Michael E. Devillier, Harold J. Hamilton, Robert D. Hempstead, Darren T. Imai, Dimitre A. Latev, David D. Roberts
  • Patent number: 6804085
    Abstract: An electromagnetic read/write system includes a contact interface formed by a pole-structure-carrying wear pad and a recording surface. The uppermost portion of the recording surface is characterized by a buffed, generally planarized topography. Lower elevations of the recording surface may be texturized or untexturized. Various methods of producing such an interface are described. The interface of the present invention provides dramatically improved longevity, i.e, wear performance through long term read/write operation.
    Type: Grant
    Filed: March 21, 1995
    Date of Patent: October 12, 2004
    Assignee: Seagate Technology, LLC
    Inventors: Michael H. Azarian, Michael A. Baldwinson, Keith R. Berding, Kaynam Chun, Garrett A. Garrettson, Christopher S. Gudeman, Harold J. Hamilton, Anthony A. Jarrami, Shinichi M. Tanaka
  • Publication number: 20040120078
    Abstract: Flexure/transducer structure employable in an electromagnetic information storage and retrieval system wherein mechanical load-bearing responsibilities and electrical-current-carrying responsibilities are merged into and shared by common structure. The invention subject matter is useable in systems characterized by contact operation, as well as by quasi-contact and noncontact operations, in relation to the recording surface in an information recording medium.
    Type: Application
    Filed: July 28, 2003
    Publication date: June 24, 2004
    Inventors: Keith R. Berding, Michael A. Baldwinson, Harold J. Hamilton, Timothy W. Martin
  • Patent number: 6600631
    Abstract: Flexure/transducer structure employable in an electromagnetic information storage and retrieval system wherein mechanical load-bearing responsibilities and electrical-current-carrying responsibilities are merged into and shared by common structure. The invention subject matter is useable in systems characterized by contact operation, as well as by quasi-contact and noncontact operations, in relation to the recording surface in an information recording medium.
    Type: Grant
    Filed: November 14, 1994
    Date of Patent: July 29, 2003
    Assignee: Censtor Corp.
    Inventors: Keith R. Berding, Michael A. Baldwinson, Harold J. Hamilton, Timothy W. Martin
  • Patent number: 6535361
    Abstract: A hard disk drive head operates in close proximity and dynamic contact with a rapidly spinning rigid disk surface, the head including a transducer with a magnetically permeable path between a poletip disposed adjacent to the disk surface and a magnetoresistive (MR) sensor situated outside the range of thermal noise generated by the surface contact. The magnetically permeable path is the same as that used to write data to the disk, eliminating errors that occur in conventional transducers having MR sensors at a separate location from the writing poletips. Moreover, the magnetically permeable path is preferably formed in a low profile, highly efficient “planar” loop that allows for manufacturing tolerances in throat height and wear of the terminal poletips from disk contact without poletip saturation or poletip smearing. The MR layer is formed in one of the first manufacturing steps atop the substrate, so that the MR layer has a relatively uniform planar template that is free from contaminants.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: March 18, 2003
    Assignee: Censtor Corp.
    Inventors: William C. Cain, Michael E. Devillier, Harold J. Hamilton, Robert D. Hempstead, Darren T. Imai, Dimitre A. Latev
  • Patent number: 6493191
    Abstract: A transducer for a hard disk drive system has a planar magnetic core and a pair of poletips that project transversely from the core for sliding contact with the disk during reading and writing. The transducer is formed entirely of thin films in the shape of a low profile table having three legs that slide on the disk, the poletips being exposed at a bottom of one of the legs for high resolution communication with the disk, the throat height of the poletips affording sufficient tolerance to allow for wear. The legs elevate the transducer from the disk sufficiently to minimize lifting by a thin air layer that moves with the spinning disk which, in combination with the small size of the thin film head allows a low load and a flexible beam and gimbal to hold the transducer to the disk.
    Type: Grant
    Filed: September 15, 1995
    Date of Patent: December 10, 2002
    Assignee: Censtor Corporation
    Inventors: William C. Cain, Richard D. Anderson, Michael A. Baldwinson, Keith R. Berding, Michael E. Devillier, Garrett A. Garrettson, Randolph S. Gluck, Harold J. Hamilton, Robert D. Hempstead, Darren T. Imai, Kwang K. Kim, Dimitre A. Latev, Alexander P. Payne, David D. Roberts
  • Publication number: 20020176210
    Abstract: A disk drive system for contact recording has a flexure beam holding a transducer at one end, the flexure beam being oriented substantially along the direction that the transducer slides on a rigid magnetic disk. The transducer has a protrusion which contacts the disk and separates the rest of the transducer from the moving air film that adjoins the spinning disk, the protrusion containing a magnetic pole structure that communicates with the disk during sliding. A preferred embodiment employs a gimbal structure which allows limited movement of the transducer relative to the flexure beam and three disk-contacting pads extending down from the transducer to make contact with the magnetic disk, at least one of the pads containing a magnetic pole structure and two of the pads trailing the third pad. An adapter provides a connection between a rotary actuator and the beam that allows the beam to approach the disk at a predictable oblique angle.
    Type: Application
    Filed: May 21, 2002
    Publication date: November 28, 2002
    Inventor: Harold J. Hamilton
  • Publication number: 20020093761
    Abstract: An information storage system includes a transducer having a loop of ferromagnetic material with pole tips separated by an nonferromagnetic gap located adjacent to a medium such as a rigid disk. During writing the separation between the pole tips and the media layer of the disk is a small fraction of the gap separation. Due to the small separation between the pole tips and the media layer, the magnetic field generated by the transducer and felt by the media has a larger perpendicular than longitudinal component, favoring perpendicular recording over longitudinal recording. The media may have an easy axis of magnetization oriented substantially along the perpendicular direction, so that perpendicular data storage is energetically favored. The transducer may also include a magnetoresistive sensor for reading magnetic information from the disk.
    Type: Application
    Filed: November 19, 2001
    Publication date: July 18, 2002
    Inventors: Alexander P. Payne, William C. Cain, Michael E. Devillier, Harold J. Hamilton, Robert D. Hempstead, Darren T. Imai, Dimitre A. Latev, David D. Roberts
  • Patent number: 6411470
    Abstract: A disk drive system for contact recording has a flexure beam holding a transducer at one end, the flexure beam being oriented substantially along the direction that the transducer slides on a rigid magnetic disk. The transducer has a protrusion which contacts the disk and separates the rest of the transducer from the moving air film that adjoins the spinning disk, the protrusion containing a magnetic pole structure that communicates with the disk during sliding. A preferred embodiment employs a gimbal structure which allows limited movement of the transducer relative to the flexure beam and three disk-contacting pads extending down from the transducer to make contact with the magnetic disk, at least one of the pads containing a magnetic pole structure and two of the pads trailing the third pad.
    Type: Grant
    Filed: March 25, 1996
    Date of Patent: June 25, 2002
    Assignee: Censtor Corporation
    Inventors: Harold J. Hamilton, Timothy W. Martin
  • Publication number: 20010055183
    Abstract: A hard disk drive head operates in close proximity and dynamic contact with a rapidly spinning rigid disk surface, the head including a transducer with a magnetically permeable path between a poletip disposed adjacent to the disk surface and a magnetoresistive (MR) sensor situated outside the range of thermal noise generated by the surface contact. The magnetically permeable path is the same as that used to write data to the disk, eliminating errors that occur in conventional transducers having MR sensors at a separate location from the writing poletips. Moreover, the magnetically permeable path is preferably formed in a low profile, highly efficient “planar” loop that allows for manufacturing tolerances in throat height and wear of the terminal poletips from disk contact without poletip saturation or poletip smearing. The MR layer is formed in one of the first manufacturing steps atop the substrate, so that the MR layer has a relatively uniform planar template that is free from contaminants.
    Type: Application
    Filed: February 28, 2001
    Publication date: December 27, 2001
    Inventors: William C. Cain, Michael E. Devillier, Harold J. Hamilton, Robert D. Hempstead, Darren T. Imai, Dimtre A. Latev
  • Patent number: 6320725
    Abstract: An information storage system having a ring head sliding on a rigid magnetic storage disk in such close proximity that the magnetic field felt by the media layer or layers of the disk has a larger perpendicular than longitudinal component so that data is stored in a perpendicular mode. The head to media separation during writing of data to the media is a small fraction of the amagnetic gap separating the poletips of the head. Reading of data may be inductive or may be via a magnetoresistive sensor which is coupled to the magnetically permeable core of the ring head far from the poletips. The media preferably has a high perpendicular anisotropy.
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: November 20, 2001
    Assignee: Censtor Corporation
    Inventors: Alexander P. Payne, William C. Cain, Michael E. DeVillier, Harold J. Hamilton, Robert D. Hempstead, Darren T. Imai, Mark A. Lauer, Dimitre A. Latev, David D. Roberts
  • Patent number: 6212047
    Abstract: An information storage system having a ring head in such close proximity to a rigid magnetic storage disk that the magnetic field felt by the media layer or layers of the disk has a larger perpendicular than longitudinal component so that data is stored in a perpendicular mode. Reading of data is accomplished with a magnetoresistive sensor which may be coupled to the magnetically permeable core of the ring head far from the poletips, which may contact the disk. The media preferably has a high perpendicular anisotropy, and may be formed in a plurality of films with crystalline structures traversing the films.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: April 3, 2001
    Assignee: Censtor Corporation
    Inventors: Alexander P. Payne, William C. Cain, Michael E. Devillier, Harold J. Hamilton, Robert D. Hempstead, Darren T. Imai, Dimitre A. Latev, Mark A. Lauer, David D. Roberts
  • Patent number: 6198607
    Abstract: A hard disk drive head operates in close proximity and dynamic contact with a rapidly spinning rigid disk surface, the head including a transducer with a magnetically permeable path between a poletip disposed adjacent to the disk surface and a magnetoresistive (MR) sensor situated outside the range of thermal noise generated by the surface contact. The magnetically permeable path is the same as that used to write data to the disk, eliminating errors that occur in conventional transducers having MR sensors at a separate location from the writing poletips. Moreover, the magnetically permeable path is preferably formed in a low profile, highly efficient “planar” loop that allows for manufacturing tolerances in throat height and wear of the terminal poletips from disk contact without poletip saturation or poletip smearing. The MR layer is formed in one of the first manufacturing steps atop the substrate, so that the MR layer has a relatively uniform planar template that is free from contaminants.
    Type: Grant
    Filed: October 2, 1996
    Date of Patent: March 6, 2001
    Assignee: Censtor Corporation
    Inventors: William C. Cain, Michael E. Devillier, Harold J. Hamilton, Robert D. Hempstead, Darren T. Imai, Dimitre A. Latev
  • Patent number: 6160685
    Abstract: An electromagnetic disk drive system including a rigid disk and electromagnetic read/write head structure and elongate flexure structure which cooperatively offer unique features and performance in the head/disk interface region. The head structure and flexure structure, in one form of the invention, are unitary and integrated and in another form are articulated. Both forms of the invention perform with substantially continuous dynamic contact with the recording surface of the disk, and both are characterized by a low effective mass and low contact force between the head and disk surface.
    Type: Grant
    Filed: August 26, 1996
    Date of Patent: December 12, 2000
    Assignee: Censtor Corp.
    Inventor: Harold J. Hamilton
  • Patent number: 5949612
    Abstract: A operationally contacting hard disk drive system has reduced friction due to lower capillary adhesion between the disk surface and a transducer in a substantially continuous sliding relationship with the surface. The disk surface has an adhesion-reducing texture that includes a microscopic RMS roughness in a range between about 1.5 and 5.5 nanometers, or a number of asperities having a mean plane to peak height in a range between about 6 and 50 nanometers. The roughness may increase in a radially graded fashion to compensate for the increased linear velocity and concomitant frictional power loss near the outer diameter of the disk. It is important that the uppermost reaches of the textured surface are smooth but not flat in order to obtain lasting low friction operation, which is accomplished by constructing the surface with a highest approximately one percent having an average radius of curvature in a range between 2 microns and 100 microns.
    Type: Grant
    Filed: August 15, 1995
    Date of Patent: September 7, 1999
    Assignee: Censtor Corp.
    Inventors: Christopher S. Gudeman, Michael H. Azarian, Michael A. Baldwinson, Keith R. Berding, Kaynam Chun, Garrett A. Garrettson, Harold J. Hamilton, Robert D. Hempstead, Dimitre A. Latev, Mark A. Lauer
  • Patent number: 5885131
    Abstract: An interactive device for lapping transducers has a body with an abrasive surface that communicates with the transducers in order to provide information for controlling the lapping and testing the transducers. The lapping body is preferably shaped as a disk, drum or tape, and communicates with the transducer using a type of signal that the transducer is designed to read and/or write. Thus for lapping a magnetic head or slider to be employed in a hard disk drive, the lapping body contains a magnetic medium layer that is either prerecorded or written by the head during lapping, while the signal received by the head is monitored and analyzed by a processor in order to determine, in part, when to terminate lapping. A series of transducers can be simultaneously lapped while individually monitored, so that each transducer can be removed from the lapping body individually upon receipt of a signal indicating that transducer has been lapped an optimal amount.
    Type: Grant
    Filed: May 24, 1997
    Date of Patent: March 23, 1999
    Assignee: Censtor Corporation
    Inventors: Michael H. Azarian, Michael A. Baldwinson, David T. Gutowski, Harold J. Hamilton, James P. Hennessy, Mark W. Parcher, Kenneth K. H. Tang
  • Patent number: 5632669
    Abstract: An interactive system for lapping transducers has an abrasive surface that communicates with the transducers in order to provide information for controlling the lapping and testing the transducers. The lapping body is preferably shaped as a disk, drum or tape, and communicates with the transducer with a type of signal that the transducer is designed to read and/or write. Thus for lapping a magnetic head or slider to be employed in a hard disk drive, the lapping body contains a magnetic medium layer that is either prerecorded or written by the head during lapping, while the signal received by the head is monitored and analyzed by a processor in order to determine, in part, when to terminate lapping. A series of transducers can be simultaneously lapped while individually monitored, so that each transducer can be removed from the lapping body individually upon receipt of a signal indicating that transducer has been lapped an optimal amount.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: May 27, 1997
    Assignee: Censtor Corporation
    Inventors: Michael H. Azarian, Michael A. Baldwinson, David T. Gutowski, Harold J. Hamilton, James P. Hennessy, Mark W. Parcher, Kenneth K. H. Tang
  • Patent number: 5557488
    Abstract: A low-mass head/flexure/conductor assembly for reading and writing information with respect to a rigid magnetic recording disk. The assembly includes a read/write transducer unit, an elongate flexure, and gimbal structure interconnecting and articulating the transducer unit and the flexure for selected, limited relative roll and pitch, without relative yaw. Conductive ribbons that form part of the gimbal structure also form part of the conductive circuit provided in the assembly. The assembly has an effective mass of no more than about 1.5-milligrams. Plural, hardened, wear-resistant feet are formed on the transducer unit for enabling sliding contact with the recording surface in a disk. The flexure may be formed of various materials, including both ceramic and nonceramic materials, and may carry applied damping material in order to control certain resonance and servo-performance characteristics.
    Type: Grant
    Filed: February 1, 1993
    Date of Patent: September 17, 1996
    Assignee: Censtor Corp.
    Inventors: Harold J. Hamilton, Timothy W. Martin
  • Patent number: 5490027
    Abstract: A low-mass head/flexure/conductor assembly for reading and writing information with respect to a rigid magnetic recording disk. The assembly includes a read/write transducer unit, an elongate flexure, and gimbal structure interconnecting and articulating the transducer unit and the flexure for selected, limited relative roll and pitch, without relative yaw. Conductive ribbons that form part of the gimbal structure also form part of the conductive circuit provided in the assembly. The assembly has an effective mass of no more than about 1.5-milligrams. Plural, hardened, wear-resistant feet are formed on the transducer unit for enabling sliding contact with the recording surface in a disk.
    Type: Grant
    Filed: October 28, 1991
    Date of Patent: February 6, 1996
    Assignee: Censtor Corp.
    Inventors: Harold J. Hamilton, Timothy W. Martin
  • Patent number: 5483025
    Abstract: A unitary micro-flexure structure and a method of making the same, wherein the structure takes the form of an elongate dielectric flexure body having a mounting end and a free end, and which is adapted for cantilevered disposition, wherein the body takes a form which is constructed entirely from thin-film deposition and patterning processes involving the deposition of a metal oxide, and further wherein the body has a topography which is at least partially determined by etch-removable surface-boundary-defining structure.
    Type: Grant
    Filed: May 15, 1995
    Date of Patent: January 9, 1996
    Assignee: Censtor Corporation
    Inventors: Harold J. Hamilton, Timothy W. Martin