Patents by Inventor David E. Fowler

David E. Fowler 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: 10891981
    Abstract: Disclosed herein are slider designs having improved trailing air flow dams, and data storage devices including such sliders. In some embodiments, a slider comprises a trailing edge and an air-bearing surface (ABS) comprising a trailing edge pad, and a trailing air flow dam coupled to the trailing edge pad, wherein, in an ABS view of the slider, the trailing air flow dam is recessed from and curves away from the trailing edge. In the ABS view, a shape of the trailing air flow dam may comprise two segments. The slider also has a leading edge and may at least one sub-ambient pressure cavity adjacent to the trailing air flow dam and disposed between the trailing air flow dam and the leading edge. A contact point of the trailing air flow dam may be at least 50 microns from a corner of the slider.
    Type: Grant
    Filed: June 3, 2020
    Date of Patent: January 12, 2021
    Assignee: Western Digital Technologies, Inc.
    Inventors: Yong Hu, Weidong Huang, David E. Fowler, Taichi Nakamura
  • Publication number: 20200312357
    Abstract: Disclosed herein are slider designs having improved trailing air flow dams, and data storage devices including such sliders. In some embodiments, a slider comprises a trailing edge and an air-bearing surface (ABS) comprising a trailing edge pad, and a trailing air flow dam coupled to the trailing edge pad, wherein, in an ABS view of the slider, the trailing air flow dam is recessed from and curves away from the trailing edge. In the ABS view, a shape of the trailing air flow dam may comprise two segments. The slider also has a leading edge and may at least one sub-ambient pressure cavity adjacent to the trailing air flow dam and disposed between the trailing air flow dam and the leading edge. A contact point of the trailing air flow dam may be at least 50 microns from a corner of the slider.
    Type: Application
    Filed: June 3, 2020
    Publication date: October 1, 2020
    Applicant: Western Digital Technologies, Inc.
    Inventors: Yong HU, Weidong HUANG, David E. FOWLER, Taichi NAKAMURA
  • Patent number: 10714135
    Abstract: Disclosed herein are slider designs having improved trailing air flow dams, and data storage devices including such sliders. In some embodiments, a slider comprises a trailing edge and an air-bearing surface (ABS) comprising a trailing edge pad, and a trailing air flow dam coupled to the trailing edge pad, wherein, in an ABS view of the slider, the trailing air flow dam is recessed from and curves away from the trailing edge. In the ABS view, a shape of the trailing air flow dam may comprise two segments. The slider also has a leading edge and may at least one sub-ambient pressure cavity adjacent to the trailing air flow dam and disposed between the trailing air flow dam and the leading edge. A contact point of the trailing air flow dam may be at least 50 microns from a corner of the slider.
    Type: Grant
    Filed: March 29, 2019
    Date of Patent: July 14, 2020
    Assignee: Western Digital Technologies, Inc.
    Inventors: Yong Hu, Weidong Huang, David E. Fowler, Taichi Nakamura
  • Patent number: 8902533
    Abstract: A disk drive is disclosed comprising a disk comprising a plurality of data tracks, and a head actuated over the disk, the head comprising an asperity sensor operable to generate a sensor signal having a magnitude based on a bias setting of the asperity sensor. The asperity sensor is configured with a first bias setting and a first asperity on the disk is detected based on the sensor signal generated at the first bias setting. The asperity sensor is configured with a second bias setting different from the first bias setting and a second asperity on the disk is detected based on the sensor signal generated at the second bias setting.
    Type: Grant
    Filed: August 30, 2013
    Date of Patent: December 2, 2014
    Assignee: Western Digital Technologies, Inc.
    Inventors: Carl E. Barlow, Chun Sei Tsai, Chirag C. Patel, Boon Sien Chew, Thomas A. O'Dell, David E. Wachenschwanz, David E. Fowler
  • Patent number: 8861317
    Abstract: A method fabricates a heat assisted magnetic recording (HAMR) transducer having an air-bearing surface (ABS) and that is optically coupled with a laser. The HAMR transducer includes a write pole, a waveguide, and at least one protective pad. The write pole has a pole tip with an ABS facing surface. The waveguide is located in a down track direction from the pole tip and directs light from the laser toward the ABS. The protective pad(s) are adjacent to the write pole and have front surface(s) at the ABS.
    Type: Grant
    Filed: May 28, 2013
    Date of Patent: October 14, 2014
    Assignee: Western Digital (Fremont), LLC
    Inventors: Wentao Yan, Yu Lo, David E. Fowler
  • Patent number: 8797667
    Abstract: A disk drive is disclosed comprising a head actuated over a disk, the head comprising a touchdown sensor comprising a resistance. A bias signal is applied at a reference value to the touchdown sensor at a reference temperature, and a corresponding reference resistance of the touchdown sensor is measured. An operating value for the bias signal is generated based on a predetermined operating temperature of the touchdown sensor, the reference resistance, the reference temperature, and a thermal coefficient of resistance (TCR) of the touchdown sensor, wherein the TCR specifies a change in temperature of the touchdown sensor relative to a change in the resistance of the touchdown sensor.
    Type: Grant
    Filed: October 15, 2012
    Date of Patent: August 5, 2014
    Assignee: Western Digital Technologies, Inc.
    Inventors: Carl E. Barlow, Chun Sei Tsai, Thomas A. O'Dell, David E. Fowler, David E. Wachenschwanz, Balvinder Singh
  • Patent number: 8760814
    Abstract: A suspension assembly for a head gimbal assembly of a disk drive includes a laminated flexure that includes a tongue for attachment of a read head. The suspension assembly includes a load beam that, in a first aspect of the present invention has a protruding dimple that contacts the tongue. In this aspect of the invention, a diamond-like carbon (DLC) coating is disposed between and contacting the dimple and the tongue. For example, the DLC may be disposed on the tongue at the location of contact with the load beam dimple. Alternatively, in a second aspect of the present invention, the tongue may have a protruding dimple that contacts the load beam. In this aspect of the invention, a DLC coating is disposed between and contacting the dimple and the load beam.
    Type: Grant
    Filed: February 26, 2013
    Date of Patent: June 24, 2014
    Assignee: Western Digital Technologies, Inc.
    Inventors: Tzong-Shii Pan, David E. Fowler, John E. Scura, Yanning Liu
  • Patent number: 8749920
    Abstract: A magnetic recording device includes a slider having an air bearing surface (ABS), a leading side, and a trailing side and a head residing on the slider. The head has a first magnetic transducer and a first heater for heating an area proximal to the first magnetic transducer. A first shield (S1) comprising a first material is on the leading side of the first magnetic transducer and a second shield (S2) comprising the first material is on the trailing side of the first magnetic transducer. A first pole (P1) comprising the first material is on the trailing side of the second shield (S2), and the first pole (P1) is between 0.6 micron and 2.0 micron thick; and the second shield (S2) is less than 0.6 micron thick. A hard disk drive includes the magnetic recording device.
    Type: Grant
    Filed: December 16, 2011
    Date of Patent: June 10, 2014
    Assignee: Western Digital (Fremont), LLC
    Inventors: Neil Knutson, David E. Fowler, Yu Lo
  • Patent number: 8643980
    Abstract: A magnetic recording device comprises a slider body having a slider interface surface and a magnetic transducer having a lower surface coplanar with an air bearing surface of the magnetic recording device. The magnetic transducer has a transducer interface surface perpendicular to the air bearing surface The magnetic recording device further comprises a piezoelectric actuator operably connecting the slider interface surface and the transducer interface surface. The piezoelectric actuator is configured to translate the magnetic transducer with respect to the slider body in a direction substantially parallel to the slider and transducer interface surfaces. The piezoelectric actuator comprises a plurality of elongate flexures disposed in parallel planes within a body of the piezoelectric actuator.
    Type: Grant
    Filed: December 15, 2008
    Date of Patent: February 4, 2014
    Assignee: Western Digital (Fremont), LLC
    Inventors: David E. Fowler, Mark R. Bragen
  • Patent number: 8456643
    Abstract: A method and system for determining a shape of a portion of an air-bearing surface (ABS) of a head residing on a slider are described. The ABS is configured to fly at a fly height from and with a velocity with respect to a disk during normal operating conditions. The method and system include driving at least one heater residing in the head while the slider is substantially at the normal operating conditions with respect to the disk and the fly height. The shape of the portion of the ABS changes in response to the heater(s) being driven. The method and system also include performing Doppler measurements on the slider while the heater is driven. The shape may then be determined based on the Doppler measurements.
    Type: Grant
    Filed: September 20, 2010
    Date of Patent: June 4, 2013
    Assignee: Western Digital (Fremont), LLC
    Inventors: Vijay Prabhakaran, Wuxing Gan, Ladislav R. Pust, David E. Fowler, Lanshi Zheng
  • Patent number: 8404099
    Abstract: A method for the electrolytic production of hydrogen where radiation excited water from a spent fuel pool of a nuclear power plant is delivered to one or more electrolysers where DC current is applied to pairs of electrodes in the electrolysers to form hydrogen and oxygen. The hydrogen is collected. The collection of hydrogen can be carried out in a grid energy storage system to produce large quantities of hydrogen during low grid demand for electricity with little or no hydrogen during high grid electricity demand.
    Type: Grant
    Filed: September 2, 2009
    Date of Patent: March 26, 2013
    Inventor: David E. Fowler
  • Publication number: 20110286129
    Abstract: A method and system for determining a shape of a portion of an air-bearing surface (ABS) of a head residing on a slider are described. The ABS is configured to fly at a fly height from and with a velocity with respect to a disk during normal operating conditions. The method and system include driving at least one heater residing in the head while the slider is substantially at the normal operating conditions with respect to the disk and the fly height. The shape of the portion of the ABS changes in response to the heater(s) being driven. The method and system also include performing Doppler measurements on the slider while the heater is driven. The shape may then be determined based on the Doppler measurements.
    Type: Application
    Filed: September 20, 2010
    Publication date: November 24, 2011
    Applicant: WESTERN DIGITAL (FREMONT), LLC
    Inventors: VIJAY PRABHAKARAN, WUXING GAN, LADISLAV R. PUST, DAVID E. FOWLER, LANSHI ZHENG
  • Patent number: 7800858
    Abstract: A method and system for providing a disk drive is described. The disk drive includes media such as one or more disks, a slider, and a head residing on the slider. The head has an air-bearing surface (ABS), a portion of which contacts the media during touchdown. The head further includes a plurality of touchdown sensors. A first touchdown sensor is proximate to the ABS, while a second touchdown sensor is distal from the ABS. The touchdown sensors are capable of detecting a temperature change of 0.1 degree Celsius or, in some embodiments, smaller.
    Type: Grant
    Filed: May 4, 2009
    Date of Patent: September 21, 2010
    Assignee: Western Digital (Fremont), LLC
    Inventors: Sateeshchandra S. Bajikar, David E. Fowler
  • Patent number: 7796356
    Abstract: A method and system for providing a disk drive is described. The disk drive includes media such as one or more disks, a slider and a head residing on the slider. The head has an air-bearing surface (ABS) and includes a touchdown sensor proximate to the ABS. The touchdown sensor is capable of detecting a temperature change of 0.1 degree Celsius or, in some embodiments, smaller. The disk drive also includes touchdown sensor control circuitry coupled with the touchdown sensor. The touchdown sensor control circuitry drives a current through the touchdown sensor and converts a signal from the touchdown sensor into an indication of whether touchdown has occurred.
    Type: Grant
    Filed: May 4, 2009
    Date of Patent: September 14, 2010
    Assignee: Western Digital (Fremont), LLC
    Inventors: David E. Fowler, Sateeshchandra S. Bajikar
  • Publication number: 20100072074
    Abstract: A method for the electrolytic production of hydrogen where radiation excited water from a spent fuel pool of a nuclear power plant is delivered to one or more electrolysers where DC current is applied to pairs of electrodes in the electrolysers to form hydrogen and oxygen. The hydrogen is collected.
    Type: Application
    Filed: September 2, 2009
    Publication date: March 25, 2010
    Inventor: David E. Fowler
  • Patent number: 7355814
    Abstract: The present invention is directed to a load/unload disk drive that includes: a rotational arm engaging a slider; a magnetic storage disk, wherein the magnetic head in the slider reads data from and/or writes data to a data zone of the magnetic storage disk; and a ramp positioned next to the magnetic storage disk. The magnetic storage disk includes a slider cleaning zone having a roughness greater than a roughness of the data zone. The slider is periodically contacted with the slider cleaning zone to remove particles collected on the slider.
    Type: Grant
    Filed: September 1, 2005
    Date of Patent: April 8, 2008
    Assignee: Maxtor Corporation
    Inventors: David E. Fowler, Erhard Schreck
  • Patent number: 6760191
    Abstract: A head suspension assembly for a disk drive that inhibits thermal pole tip protrusion includes a slider assembly having a slider exterior surface including a trailing surface, a slider interior region that is defined by the slider exterior surface, and a write head having an electrically coupled write coil positioned within the slider interior region. The write coil generates heat during write operations of the disk drive. The slider assembly also includes a heat dissipater positioned substantially within the slider interior region. The heat dissipater is electrically isolated from the write coil, and has a thermal conductivity of at least approximately 50 W/mK.
    Type: Grant
    Filed: February 4, 2002
    Date of Patent: July 6, 2004
    Assignee: Maxtor Corporation
    Inventors: Wentao Yan, David E. Fowler
  • Patent number: 6654205
    Abstract: Sliders having air bearing surfaces are disclosed for use with magnetic recording and reading heads in a magnetic disk drive assembly to reduce the pressure gradients resulting from the flow of air between the slider and the spinning disk. To relieve such pressure gradient, the bottom surface of the air bearing surface at or near the trailing edge includes one or more recesses, which may be one or more steps, inclined ramps, curves or other configurations. Other surfaces of the slider may also include recesses to relieve these pressures. The sliders having air bearing surfaces may be attached to, or integral with, a magnetic recording or reading head in a magnetic disk drive assembly. A method of reducing the formation of pressure gradients is also disclosed whereby air flow between the disk and the head creates a pressure greater than atmospheric, at least a part of which is released through a recess on the air bearing surface of the slider.
    Type: Grant
    Filed: November 1, 1999
    Date of Patent: November 25, 2003
    Assignee: Maxtor Corporation
    Inventors: Matthew A. O'Hara, David E. Fowler
  • Patent number: 5554520
    Abstract: Novel plasmids comprising genes which code for the alcohol dehydrogenase and pyruvate decarboxylase are have been transformed with genes coding for alcohol dehydrogenase and pyruvate. By virtue of their transformation with these genes, the recombinant hosts are capable of producing significant amounts of ethanol as a fermentation product. Also disclosed are methods for increasing the growth of recombinant hosts and methods for reducing the accumulation of undesirable metabolic products in the growth medium of these hosts. Also disclosed are recombinant host capable of producing significant amounts of ethanol as a fermentation product of oligosaccharides and plasmids comprising genes encoding polysaccharases, in addition to the genes described above which code for the alcohol dehydrogenase and pyruvate decarboxylase. Further, methods are described for producing ethanol from oligomeric feedstock using the recombinant hosts described above.
    Type: Grant
    Filed: March 5, 1993
    Date of Patent: September 10, 1996
    Assignee: BioEnergy International, L.C.
    Inventors: David E. Fowler, Philip G. Horton, Arie Ben-Bassat
  • Patent number: 5487989
    Abstract: Novel plasmids comprising genes which code for the alcohol dehydrogenase and pyruvate decarboxylase are described. Also described are recombinant hosts which have been transformed with genes coding for alcohol dehydrogenase and pyruvate. By virtue of their transformation with these genes, the recombinant hosts are capable of producing significant amounts of ethanol as a fermentation product. Also disclosed are methods for increasing the growth of recombinant hosts and methods for reducing the accumulation of undesirable metabolic products in the growth medium of these hosts. Also disclosed are recombinant host capable of producing significant amounts of ethanol as a fermentation product of oligosaccharides and plasmids comprising genes encoding polysaccharases, in addition to the genes described above which code for the alcohol dehydrogenase and pyruvate decarboxylase. Further, methods are described for producing ethanol from oligomeric feedstock using the recombinant hosts described above.
    Type: Grant
    Filed: September 17, 1992
    Date of Patent: January 30, 1996
    Assignee: Bioenergy International, L.C.
    Inventors: David E. Fowler, Philip G. Horton, Arie Ben-Bassat