Patents by Inventor Parul Agrawal

Parul Agrawal 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: 7164557
    Abstract: An air bearing burnish slider burnishes very small asperities and cleans the loose particles that adhere to the magnetic recording media. The slider applies a controllable contact force to effectively burnish disk asperities or partially attached particles. In addition, the slider cleans the loose particles effectively while flying in a stable fashion. In a low pitch design, diagonal rails push particles away from the disk surface and trailing edge pads contact the disk at lower linear velocities. Rail pads retain loose contamination and debris in their pockets and burnish asperities. Another design provides a milder burnish force and flies in a high pitch configuration. The trailing edge pads provide stable contacts and the rails help in sweeping away debris. In both designs, the contact forces can be controlled by adjusting linear velocities. A step taper at the leading edge provides a pitch-producing lift force.
    Type: Grant
    Filed: February 23, 2004
    Date of Patent: January 16, 2007
    Assignee: Hitachi Global Storage Technologies Netherlands BV
    Inventors: Parul Agrawal, Hang Fai Ngo, Charles Lee, Li-Chung Lee, Ullal Vasant Nayak, Stephen Olson, Robert N. Payne, Christopher Ramm
  • Patent number: 6935925
    Abstract: An in-situ technique for the acoustic emission monitoring of burnish heads while they are cleaning or burnishing magnetic media is described. The burnishing process is monitored and controlled to identify interaction or contact between the head and media due to, for example, burnish head damage, substrate curvature problems, and lube pick-up problems. A piezoelectric sensor is mounted on the burnish arm that holds the burnish heads. When head-disk interaction occurs, stress waves travel through the head to the sensor and an amplified signal is gathered in a tester database as an acoustic emission. Abnormal conditions will trigger an unusual emission that is detected to trigger an alert.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: August 30, 2005
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Parul Agrawal, Bradley Frederick Baumgartner, Norman Chu, Charles Lee, Tony Mello, Christopher Ramm, Bob Clyde Robinson
  • Publication number: 20050185343
    Abstract: An air bearing burnish slider burnishes very small asperities and cleans the loose particles that adhere to the magnetic recording media. The slider applies a controllable contact force to effectively burnish disk asperities or partially attached particles. In addition, the slider cleans the loose particles effectively while flying in a stable fashion. In a low pitch design, diagonal rails push particles away from the disk surface and trailing edge pads contact the disk at lower linear velocities. Rail pads retain loose contamination and debris in their pockets and burnish asperities. Another design provides a milder burnish force and flies in a high pitch configuration. The trailing edge pads provide stable contacts and the rails help in sweeping away debris. In both designs, the contact forces can be controlled by adjusting linear velocities. A step taper at the leading edge provides a pitch-producing lift force.
    Type: Application
    Filed: February 23, 2004
    Publication date: August 25, 2005
    Inventors: Parul Agrawal, Hang Ngo, Charles Lee, Li-Chung Lee, Ullal Nayak, Stephen Olson, Robert Payne, Christopher Ramm