Patents by Inventor Christopher G. Dunn

Christopher G. Dunn 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: 11741990
    Abstract: In a disk drive having a flexible circuit tail that is routed within a recess in the actuator arm, a dielectric spacer is added to the top of the tail in order to space the circuit traces within the tail further away from the electrically conductive actuator arm, and to make more repeatable that spacing. The added spacing reduces electrical coupling and thus increases the bandwidth of the circuit. The spacer can be in the form of a section of the same viscoelastic material that is used elsewhere as a vibration dampener on the suspension, the viscoelastic material being adhered to the tail before the tail is inserted within the recess. Alternatively, the spacer can be a thickened region of the flexible circuit covercoat in the area where the tail will reside within the recess.
    Type: Grant
    Filed: August 6, 2018
    Date of Patent: August 29, 2023
    Assignee: Magnecomp Corporation
    Inventors: Christopher G. Dunn, Benjapa Tanampee
  • Publication number: 20180342263
    Abstract: In a disk drive having a flexible circuit tail that is routed within a recess in the actuator arm, a dielectric spacer is added to the top of the tail in order to space the circuit traces within the tail further away from the electrically conductive actuator arm, and to make more repeatable that spacing. The added spacing reduces electrical coupling and thus increases the bandwidth of the circuit. The spacer can be in the form of a section of the same viscoelastic material that is used elsewhere as a vibration dampener on the suspension, the viscoelastic material being adhered to the tail before the tail is inserted within the recess. Alternatively, the spacer can be a thickened region of the flexible circuit covercoat in the area where the tail will reside within the recess.
    Type: Application
    Filed: August 6, 2018
    Publication date: November 29, 2018
    Inventors: Christopher G. Dunn, Benjapa Tanampee
  • Patent number: 10043541
    Abstract: In a disk drive having a flexible circuit tail that is routed within a recess in the actuator arm, a dielectric spacer is added to the top of the tail in order to space the circuit traces within the tail further away from the electrically conductive actuator arm, and to make more repeatable that spacing. The added spacing reduces electrical coupling and thus increases the bandwidth of the circuit. The spacer can be in the form of a section of the same viscoelastic material that is used elsewhere as a vibration dampener on the suspension, the viscoelastic material being adhered to the tail before the tail is inserted within the recess. Alternatively, the spacer can be a thickened region of the flexible circuit covercoat in the area where the tail will reside within the recess.
    Type: Grant
    Filed: November 12, 2016
    Date of Patent: August 7, 2018
    Assignee: Magnecomp Corporation
    Inventors: Christopher G. Dunn, Benjapa Tanampee
  • Patent number: 9330693
    Abstract: An electrical circuit for a disk drive suspension has a first signal trace above a grounded support layer which is typically stainless steel, and a second signal trace below the support layer, the two signal traces typically being opposite polarities of a differential signal pair. The support layer between the two signal traces is windowed, and the two traces are physically separated by a distance that equals the nominal thickness of the support layer plus the thicknesses of the top and bottom dielectric layers that separate the signal traces from the support layer. The physical separation combined with the windowing reduces the impedance and increases the bandwidth of the differential pair. The impedance can be controlled by the percentage of windowing in the support layer.
    Type: Grant
    Filed: September 19, 2014
    Date of Patent: May 3, 2016
    Assignee: MAGNECOMP CORPORATION
    Inventors: Peter Hahn, Benjapa Tanampee, Jatuporn Nakarpha, Christopher G. Dunn
  • Patent number: 8810972
    Abstract: An electrical interconnect from a suspension electrical circuit to a PZT microactuator motor includes copper plated onto a first side of a stainless steel support layer and gold plated onto a second and opposite side of the stainless steel support layer, with the gold plated stainless steel surface bonded to the PZT motor surface by conductive epoxy. The stainless steel may have a via etched into it to the copper surface before the gold plating step which then plates both the stainless steel and the copper with gold, so that the conductive epoxy is in physical and electrical contact with both the gold plated stainless steel and thus in electrical contact with the copper, and also in direct physical and electrical contact with the gold plated copper.
    Type: Grant
    Filed: December 10, 2013
    Date of Patent: August 19, 2014
    Assignee: Magnecomp Corporation
    Inventor: Christopher G. Dunn
  • Patent number: 7348045
    Abstract: A dielectric film for use as a substrate for a flexible circuit comprises a polymer selected from the group consisting of liquid crystal polymers and polyimide copolymers including carboxylic ester structural units in the polymeric backbone. The dielectric film has a thickness from about 25 ?m to about 60 ?m including at least one thinned, recessed region wherein the thickness is reduced to less than 15 ?m, as required for use of the dielectric film in e.g. ink jet print head, hard disk drive head gimbal assembly and touch sensor applications.
    Type: Grant
    Filed: September 5, 2002
    Date of Patent: March 25, 2008
    Assignee: 3M Innovative Properties Company
    Inventors: Rui Yang, Christopher G. Dunn, Nathan P. Kreutter
  • Patent number: 6735052
    Abstract: A disk drive suspension assembly including an elongated polymeric base member having a plurality of traces formed directly on a first surface thereof and a reference voltage layer formed on a second surface thereof. A support member is formed directly on at least a portion of the reference voltage layer. The plurality of traces overlay at least a portion of the reference voltage layer. The reference voltage layer is formed from a first electrically conductive material and the support member is formed from a second electrically conductive material. The first electrically conductive material providing substantially greater electrical conductivity and substantially less tensile strength than the second electrically conductive material. The support member includes a head gimbal portion having a first thickness and a load beam portion having a second thickness. The second thickness is substantially greater than the first thickness.
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: May 11, 2004
    Assignee: 3M Innovative Properties Company
    Inventors: Christopher G. Dunn, Nathan P. Kreutter
  • Publication number: 20040046835
    Abstract: A dielectric film for use as a substrate for a flexible circuit comprises a polymer selected from the group consisting of liquid crystal polymers and polyimide copolymers including carboxylic ester structural units in the polymeric backbone. The dielectric film has a thickness from about 25 &mgr;m to about 60 &mgr;m including at least one thinned, recessed region wherein the thickness is reduced to less than 15 &mgr;m, as required for use of the dielectric film in e.g. ink jet print head, hard disk drive head gimbal assembly and touch sensor applications.
    Type: Application
    Filed: September 5, 2002
    Publication date: March 11, 2004
    Inventors: Rui Yang, Christopher G. Dunn, Nathan P. Kreutter
  • Publication number: 20030053258
    Abstract: A disk drive suspension assembly including an elongated polymeric base member having a plurality of traces formed directly on a first surface thereof and a reference voltage layer formed on a second surface thereof. A support member is formed directly on at least a portion of the reference voltage layer. The plurality of traces overlay at least a portion of the reference voltage layer. The reference voltage layer is formed from a first electrically conductive material and the support member is formed from a second electrically conductive material. The first electrically conductive material providing substantially greater electrical conductivity and substantially less tensile strength than the second electrically conductive material. The support member includes a head gimbal portion having a first thickness and a load beam portion having a second thickness. The second thickness is substantially greater than the first thickness.
    Type: Application
    Filed: September 27, 2002
    Publication date: March 20, 2003
    Inventors: Christopher G. Dunn, Nathan P. Kreutter
  • Patent number: 6480359
    Abstract: A disk drive suspension assembly including an elongated polymeric base member having a plurality of traces formed directly on a first surface thereof and a reference voltage layer formed on a second surface thereof. A support member is formed directly on at least a portion of the reference voltage layer. The plurality of traces overlay at least a portion of the reference voltage layer. The reference voltage layer is formed from a first electrically conductive material and the support member is formed from a second electrically conductive material. The first electrically conductive material providing substantially greater electrical conductivity and substantially less tensile strength than the second electrically conductive material. The support member includes a head gimbal portion having a first thickness and a load beam portion having a second thickness. The second thickness is substantially greater than the first thickness.
    Type: Grant
    Filed: May 9, 2000
    Date of Patent: November 12, 2002
    Assignee: 3M Innovative Properties Company
    Inventors: Christopher G. Dunn, Nathan P. Kreutter