Patents by Inventor Yoshiyuki Nagasaka

Yoshiyuki Nagasaka 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: 7839597
    Abstract: A difference value between a gain control value when a head comes into contact with a recording medium and a gain control value when the head floats with respect to the recording medium by a target floating amount is stored in advance. When the information access device is actually operated, supply power to a heater is adjusted to once bring the head into contact with the recording medium, a first gain control value adjusted by a gain control section when the head comes into contact with the recording medium is obtained, a second gain control value to be adjusted by the gain control section when the head floats from the recording medium by the target floating amount is obtained from the first gain control value and the difference value, and the supply power to the heater is adjusted such that the second gain control value is supplied to a gain variable amplifier by the gain control section.
    Type: Grant
    Filed: March 25, 2009
    Date of Patent: November 23, 2010
    Assignee: Toshiba Storage Device Corporation
    Inventor: Yoshiyuki Nagasaka
  • Patent number: 7697232
    Abstract: A storage device has a head that floats over a rotating storage medium. The storage device includes a measuring unit that measures the operating time and a head slider having a head element. The head element includes a reading element, a writing element and a heater, and a control unit that controls a protruding amount of the head element, by issuing an instruction causing an amount of power of a first predetermined value to be supplied to the heater until the amount of time measured by the measuring unit becomes a predetermined value. When the amount of time exceeds the predetermined value, the control unit cause an amount of power of a second predetermined value that is lower than the first predetermined value.
    Type: Grant
    Filed: February 21, 2008
    Date of Patent: April 13, 2010
    Assignee: Toshiba Storage Device Corporation
    Inventors: Toshiyuki Yokota, Yoshiyuki Nagasaka
  • Publication number: 20100027157
    Abstract: According to an aspect of the embodiment, an MPU obtains, as a first gain value from a RDC, a gain value of a servo signal when data is read from a magnetic storage medium, and obtains, as a second gain value from the RDC, the gain value of the servo signal when data is written to the magnetic storage medium. The MPU controls supplied power for controlling flying height of the magnetic head when data is written to the magnetic storage medium based on a result of the comparing between the first gain value and the second gain value.
    Type: Application
    Filed: June 25, 2009
    Publication date: February 4, 2010
    Applicant: FUJITSU LIMITED
    Inventor: Yoshiyuki Nagasaka
  • Publication number: 20090244766
    Abstract: A difference value between a gain control value when a head comes into contact with a recording medium and a gain control value when the head floats with respect to the recording medium by a target floating amount is stored in advance. When the information access device is actually operated, supply power to a heater is adjusted to once bring the head into contact with the recording medium, a first gain control value adjusted by a gain control section when the head comes into contact with the recording medium is obtained, a second gain control value to be adjusted by the gain control section when the head floats from the recording medium by the target floating amount is obtained from the first gain control value and the difference value, and the supply power to the heater is adjusted such that the second gain control value is supplied to a gain variable amplifier by the gain control section.
    Type: Application
    Filed: March 25, 2009
    Publication date: October 1, 2009
    Applicant: FUJITSU LIMITED
    Inventor: Yoshiyuki NAGASAKA
  • Publication number: 20080239551
    Abstract: A storage device has a head that floats over a rotating storage medium. The storage device includes a measuring unit that measures the operating time and a head slider having a head element. The head element includes a reading element, a writing element and a heater, and a control unit that controls a protruding amount of the head element, by issuing an instruction causing an amount of power of a first predetermined value to be supplied to the heater until the amount of time measured by the measuring unit becomes a predetermined value. When the amount of time exceeds the predetermined value, the control unit cause an amount of power of a second predetermined value that is lower than the first predetermined value.
    Type: Application
    Filed: February 21, 2008
    Publication date: October 2, 2008
    Applicant: FUJITSU LIMITED
    Inventors: Toshiyuki Yokota, Yoshiyuki Nagasaka
  • Patent number: 7212363
    Abstract: A magnetic disk apparatus formats a single data frame as a single sector. The magnetic disk apparatus includes a read-out control unit that controls to read-out sector data by emulating an existing format (e.g., “512 bytes/sector”), and a write-in control unit that controls to write sector data by emulating the existing format (e.g., “512 bytes/sector”), when the magnetic disk apparatus receives a read command or a write command based on a format (e.g., “512 bytes/sector”) that is different from a format of the magnetic disk apparatus (i.e., one sector/one data frame) from a host.
    Type: Grant
    Filed: November 12, 2004
    Date of Patent: May 1, 2007
    Assignee: Fujitsu Limited
    Inventor: Yoshiyuki Nagasaka
  • Publication number: 20060007590
    Abstract: A magnetic disk apparatus formats a single data frame as a single sector. The magnetic disk apparatus includes a read-out control unit that controls to read-out sector data by emulating an existing format (e.g., “512 bytes/sector”), and a write-in control unit that controls to write sector data by emulating the existing format (e.g., “512 bytes/sector”), when the magnetic disk apparatus receives a read command or a write command based on a format (e.g., “512 bytes/sector”) that is different from a format of the magnetic disk apparatus (i.e., one sector/one data frame) from a host.
    Type: Application
    Filed: November 12, 2004
    Publication date: January 12, 2006
    Inventor: Yoshiyuki Nagasaka
  • Patent number: 5956200
    Abstract: Disclosed are a method of and an apparatus for controlling a magnetic disc drive including a magnetic head in which a write head and a read head are separated. The control method comprises: a step of calculating a moving quantity up to a designated target track position in accordance with a write instruction or a read instruction and calculating a moving quantity from the moving quantity up to the target track position and a yaw angle offset quantity in accordance with the read instruction or the write instruction; and a step of locating the magnetic head in the target track position by seek-controlling the rotary type actuator in accordance with the calculated moving quantity.
    Type: Grant
    Filed: March 1, 1996
    Date of Patent: September 21, 1999
    Assignee: Fujitsu Limited
    Inventors: Keiichi Kohno, Tsuyoshi Takahashi, Masayoshi Ishii, Yoshiyuki Nagasaka, Tamotsu Kozuka, Susumu Yoshida
  • Patent number: 5831782
    Abstract: Disclosed are a method of and an apparatus for controlling a magnetic disc drive including a magnetic head in which a write head and a read head are separated. The control method comprises: a step of calculating a moving quantity up to a designated target track position in accordance with a write instruction or a read instruction and calculating a moving quantity from the moving quantity up to the target track position and a yaw angle offset quantity in accordance with the read instruction or the write instruction; and a step of locating the magnetic head in the target track position by seek-controlling the rotary type actuator in accordance with the calculated moving quantity.
    Type: Grant
    Filed: August 19, 1996
    Date of Patent: November 3, 1998
    Assignee: Fujitsu Limited
    Inventors: Keiichi Kohno, Tsuyoshi Takahashi, Masayoshi Ishii, Yoshiyuki Nagasaka, Tamotsu Kozuka, Susumu Yoshida
  • Patent number: 5623474
    Abstract: A training pattern which is used for a waveform equalization is preliminarily recorded on a disk medium and the waveform equalization to suppress an interference between bits of a read waveform by an adaptive type equalizer is performed. An error detector executes a training operation for adjusting an equalization amount of the adaptive type equalizer so as to minimize an error due to the interference between bits of the read waveform on the basis of the training pattern read out from the disk medium. A bit pattern detector detects a predetermined bit pattern "00" included in the training pattern and instructs the start of the training operation to the error detector by the detection of the first bit pattern "00". A counter counts the number of detection times of the bit pattern "00" by the bit pattern detector and instructs the end of the training operation to the error detector when the number of detection times reaches a predetermined value.
    Type: Grant
    Filed: August 10, 1995
    Date of Patent: April 22, 1997
    Assignee: Fujitsu Limited
    Inventors: Umeo Oshio, Yoshiyuki Nagasaka