Patents by Inventor Anandan Vengadasalam

Anandan Vengadasalam 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).

  • Bulk erase tool to erase a perpendicular media recording disk of a disk drive
    Patent number: 8379363
    Abstract: A bulk erase tool to erase a perpendicular media recording (PMR) disk of a disk drive is disclosed. The bulk erase tool comprises a housing to receive a disk drive and at least one of a first pair of magnets mounted in the housing to be positioned above the received disk drive to provide a magnetic field to erase the top side of the disk and a second pair of magnets mounted in the housing to be positioned below the disk drive to provide a magnetic field to erase the bottom side of the disk.
    Type: Grant
    Filed: March 26, 2010
    Date of Patent: February 19, 2013
    Assignee: Western Digital Technologies, Inc.
    Inventors: Pusphanathan Kolunthavelu, Anandan Vengadasalam
  • Servo writer with retract capacitor for generating a VCM driving current during a power failure
    Patent number: 7974038
    Abstract: A servo writer is disclosed for writing servo data onto a disk of a disk drive. The servo writer comprises a push-pin operable to contact an actuator arm of the disk drive, an actuator for actuating the push pin, and a retract capacitor. The retract capacitor is charged, and the actuator actuates the push-pin in order to position the head radially over the disk. If a power failure occurs while actuating the push-pin, a current is applied from the retract capacitor to a voice coil of the actuator arm in order to retract the actuator arm.
    Type: Grant
    Filed: December 10, 2007
    Date of Patent: July 5, 2011
    Assignee: Western Digital Technologies, Inc.
    Inventors: Puspanathan Krishnan, Anandan Vengadasalam
  • Heating a head disk assembly for a time interval prior to writing spiral servo tracks to the disk
    Patent number: 7940487
    Abstract: A method of writing spiral servo tracks to a disk of a disk drive is disclosed. The disk is heated by applying a heating power to a heater for a time interval. After the time interval, the heating power is reduced, and the spiral servo tracks are written to the disk. In one embodiment, an external spiral servo writer comprises a heat lamp for heating an exterior surface of a head disk assembly (HDA) prior to writing spiral servo tracks to the disk.
    Type: Grant
    Filed: June 24, 2008
    Date of Patent: May 10, 2011
    Assignee: Western Digital Technologies, Inc.
    Inventors: Puspanathan Krishnan, Anandan Vengadasalam, Hilmy Ahmad@Mohamad
  • SERVO WRITER WITH RETRACT CAPACITOR FOR GENERATING A VCM DRIVING CURRENT DURING A POWER FAILURE
    Publication number: 20090147396
    Abstract: A servo writer is disclosed for writing servo data onto a disk of a disk drive. The servo writer comprises a push-pin operable to contact an actuator arm of the disk drive, an actuator for actuating the push pin, and a retract capacitor. The retract capacitor is charged, and the actuator actuates the push-pin in order to position the head radially over the disk. If a power failure occurs while actuating the push-pin, a current is applied from the retract capacitor to a voice coil of the actuator arm in order to retract the actuator arm.
    Type: Application
    Filed: December 10, 2007
    Publication date: June 11, 2009
    Inventors: Puspanathan Krishnan, Anandan Vengadasalam