Patents by Inventor Manabu Saikawa

Manabu Saikawa 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: 8018673
    Abstract: A disk drive. The disk drive includes a plurality of head-sliders, an actuator, a plurality of clearance adjustment sections, and a controller. Each head-slider includes a slider and a magnetic-recording head on the slider for accessing a disk for storing data. The plurality of head-sliders is secured to the actuator that is configured to move the plurality of head-sliders concurrently. Each clearance adjustment section corresponds to each head-slider of the plurality of head-sliders and adjusts a clearance of the corresponding head-slider. In addition, the controller is configured to position the actuator by servo control with a first head-slider selected from the plurality of head-sliders, to change a clearance of a second head-slider different from the first head-slider by controlling a clearance adjustment section of the second head-slider to bring the second head-slider into contact with a disk, and to detect the contact to measure the clearance of the second head-slider.
    Type: Grant
    Filed: November 13, 2009
    Date of Patent: September 13, 2011
    Assignee: Hitachi Global Storage Technologies, Netherlands B.V.
    Inventors: Manabu Saikawa, Atsushi Takeichi, Yuki Hashimoto, Kenji Kuroki, Mitsuhiro Shoda
  • Publication number: 20100123970
    Abstract: A disk drive. The disk drive includes a plurality of head-sliders, an actuator, a plurality of clearance adjustment sections, and a controller. Each head-slider includes a slider and a magnetic-recording head on the slider for accessing a disk for storing data. The plurality of head-sliders is secured to the actuator that is configured to move the plurality of head-sliders concurrently. Each clearance adjustment section corresponds to each head-slider of the plurality of head-sliders and adjusts a clearance of the corresponding head-slider. In addition, the controller is configured to position the actuator by servo control with a first head-slider selected from the plurality of head-sliders, to change a clearance of a second head-slider different from the first head-slider by controlling a clearance adjustment section of the second head-slider to bring the second head-slider into contact with a disk, and to detect the contact to measure the clearance of the second head-slider.
    Type: Application
    Filed: November 13, 2009
    Publication date: May 20, 2010
    Inventors: Manabu Saikawa, Atsushi Takeichi, Yuki Hashimoto, Kenji Kuroki, Mitsuhiro Shoda
  • Patent number: 7573669
    Abstract: Embodiments in accordance with the present invention ensure that the pitch of a servo write track is accurately controlled. According to one embodiment of the present invention, a Self Servo Write (SSW) uses different methods and sequences to identify read-write offsets (RWOs) and calculate target positions in inner and outer diameter sides of a magnetic disk. In the inner diameter-side area, the SSW controller uses the readout of a radial pattern written on a recording surface and a reference value to identify the RWO. The SSW controller uses the RWO value identified in the inner diameter-side area to anticipate an RWO value in the outer diameter-side area. In the outer diameter-side area, the SSW controller uses the anticipated RWO value to determine the target position of each servo write track.
    Type: Grant
    Filed: April 19, 2007
    Date of Patent: August 11, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Manabu Saikawa, Atsushi Takeichi, Kazuhiko Washizu
  • Publication number: 20070247742
    Abstract: Embodiments in accordance with the present invention ensure that the pitch of a servo write track is accurately controlled. According to one embodiment of the present invention, a Self Servo Write (SSW) uses different methods and sequences to identify read-write offsets (RWOs) and calculate target positions in inner and outer diameter sides of a magnetic disk. In the inner diameter-side area, the SSW controller uses the readout of a radial pattern written on a recording surface and a reference value to identify the RWO. The SSW controller uses the RWO value identified in the inner diameter-side area to anticipate an RWO value in the outer diameter-side area. In the outer diameter-side area, the SSW controller uses the anticipated RWO value to determine the target position of each servo write track.
    Type: Application
    Filed: April 19, 2007
    Publication date: October 25, 2007
    Applicant: Hitachi Global Storage Technologies Inc.
    Inventors: Manabu Saikawa, Atsushi Takeichi, Kazuhiko Washizu
  • Patent number: 7173785
    Abstract: Provided is a data storage device in which read and write heads can be desirably located with respect to servo tracks from the viewpoint of linearity of a PES on the premise that a read write offset exists. A read write offset value, which is a deviation amount between write and read heads in a radial direction of a disk-shaped storage medium, is set equivalent to an integer number N of servo tracks.
    Type: Grant
    Filed: June 19, 2003
    Date of Patent: February 6, 2007
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Manabu Saikawa, Hirofumi Yanase
  • Patent number: 7126772
    Abstract: Provided is a data storage device in which servo track pitch varies within a predetermined region in a radial direction of a disk-shaped storage medium.
    Type: Grant
    Filed: January 24, 2005
    Date of Patent: October 24, 2006
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Manabu Saikawa, Hirofumi Yanase
  • Publication number: 20050122608
    Abstract: Provided is a data storage device in which read and write heads can be desirably located with respect to servo tracks from the viewpoint of linearity of a PES on the premise that a read write offset exists. A read write offset value, which is a deviation amount between write and read heads in a radial direction of a disk-shaped storage medium, is set equivalent to an integer number N of servo tracks.
    Type: Application
    Filed: January 24, 2005
    Publication date: June 9, 2005
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Manabu Saikawa, Hirofumi Yanase
  • Publication number: 20040057151
    Abstract: Provided is a data storage device in which read and write heads can be desirably located with respect to servo tracks from the viewpoint of linearity of a PES on the premise that a read write offset exists. A read write offset value, which is a deviation amount between write and read heads in a radial direction of a disk-shaped storage medium, is set equivalent to an integer number N of servo tracks.
    Type: Application
    Filed: June 19, 2003
    Publication date: March 25, 2004
    Applicant: Hitachi Global Storage Technologies
    Inventors: Manabu Saikawa, Hirofumi Yanase