Patents by Inventor Masahide Kanegae

Masahide Kanegae 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).

  • Publication number: 20160343400
    Abstract: According to one embodiment, a magnetic disk device includes a disk and a controller. The disk includes a storage area having a plurality of tracks. The controller groups, data sector by data sector into a plurality of groups forming a first set of groups, a plurality of data sectors arranged on each of the plurality of tracks, such that those of the plurality of groups that are arranged at least adjacent to each other differ in position from each other. Further, the controller arranges a plurality of redundant sectors corresponding to the plurality of groups in a free area in the storage area.
    Type: Application
    Filed: August 25, 2015
    Publication date: November 24, 2016
    Inventors: Shuuichi Kojima, Masahide Kanegae
  • Patent number: 9235472
    Abstract: According to one embodiment, a drive array apparatus includes a plurality of data storage drives constituting a drive array and a controller. The controller divides all data storage areas of each of the data storage drives into a plurality of logical unit areas and associates and manages each of the logical unit areas and each of the data storage drives. The controller identifies a logical unit area of an error occurrence object based on a notification from a data storage drive where an error occurred, restores data of the identified logical unit area, and performs reconfiguration processing of the drive array.
    Type: Grant
    Filed: September 4, 2013
    Date of Patent: January 12, 2016
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Nobuhiro Sugawara, Hironori Kanno, Yasuyuki Nagashima, Seiji Toda, Kotaro Yamamoto, Masahide Kanegae, Keiichi Yorimitsu
  • Patent number: 9177582
    Abstract: In a disk apparatus, media include first and second surfaces having first and second servo patterns which are read at different timings by first and second heads. A controller controls the first head based on a first demodulated position obtained by demodulating the first servo pattern and a target position. The controller calculates a first estimated demodulated position from the demodulated position and a first demodulated velocity based on the first servo patterns, calculates a second estimated demodulated position from the first demodulated position and a second demodulated velocity based on the second servo patterns, and stops writing operation of the first head in accordance with one of the first and second estimated demodulated positions exceeding a threshold.
    Type: Grant
    Filed: April 23, 2015
    Date of Patent: November 3, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takayuki Kawabe, Masahide Kanegae
  • Patent number: 8929019
    Abstract: According to at least one embodiment, a read/write apparatus includes a read module and a positioning module. The read module reads data of a predetermined data track using a read head. The positioning module positions the read head in accordance with an index indicating how much the read head reads data of a neighboring data track of the predetermined data track when the read head reads data of the predetermined data track.
    Type: Grant
    Filed: December 19, 2012
    Date of Patent: January 6, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Naoki Tagami, Masahide Kanegae
  • Publication number: 20140304547
    Abstract: According to one embodiment, a drive array apparatus includes a plurality of data storage drives constituting a drive array and a controller. The controller divides all data storage areas of each of the data storage drives into a plurality of logical unit areas and associates and manages each of the logical unit areas and each of the data storage drives. The controller identifies a logical unit area of an error occurrence object based on a notification from a data storage drive where an error occurred, restores data of the identified logical unit area, and performs reconfiguration processing of the drive array.
    Type: Application
    Filed: September 4, 2013
    Publication date: October 9, 2014
    Inventors: Nobuhiro Sugawara, Hironori Kanno, Yasuyuki Nagashima, Seiji Toda, Kotaro Yamamoto, Masahide Kanegae, Keiichi Yorimitsu
  • Publication number: 20140029133
    Abstract: According to at least one embodiment, a read/write apparatus includes a read module and a positioning module. The read module reads data of a predetermined data track using a read head. The positioning module positions the read head in accordance with an index indicating how much the read head reads data of a neighboring data track of the predetermined data track when the read head reads data of the predetermined data track.
    Type: Application
    Filed: December 19, 2012
    Publication date: January 30, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Naoki TAGAMI, Masahide KANEGAE
  • Publication number: 20110317302
    Abstract: According to one embodiment, a disk storage apparatus includes a read module, a measuring module, and a compensating module. The read module is configured to read first and second signals recorded on a disk, from which to measure the flying height of a head. The measuring module is configured to calculate the flying height of the head from the first and second measurement signals read by the read module. The compensating module is configured to use the data representing the flying height representing error resulting from superparamagnetic effect, thereby compensating for the flying height measured by the measuring module.
    Type: Application
    Filed: March 15, 2011
    Publication date: December 29, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yuji SAKAI, Kazuhito SHIMOMURA, Masahide KANEGAE
  • Patent number: 8027118
    Abstract: According to one embodiment, an apparatus for controlling a head includes a transmitting module and a controller. The transmitting module is configured to transmit a write signal to a magnetic head having a spin torque oscillator at the time of recording data. The controller is configured to supply a drive signal that has a level higher than the ordinary level for a prescribed effective time, to the spin-torque oscillator in response to an input write gate that instructs the recording of data. During a period other than prescribed effective time, the controller supplies a drive signal having the ordinary level to the spin-torque oscillator.
    Type: Grant
    Filed: July 26, 2010
    Date of Patent: September 27, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Toru Ezawa, Shuichi Kojima, Masahide Kanegae, Kenichiro Yamada, Katsuhiko Koui, Masayuki Takagishi
  • Publication number: 20110128648
    Abstract: According to one embodiment, an apparatus for controlling a head includes a transmitting module and a controller. The transmitting module is configured to transmit a write signal to a magnetic head having a spin torque oscillator at the time of recording data. The controller is configured to supply a drive signal that has a level higher than the ordinary level for a prescribed effective time, to the spin-torque oscillator in response to an input write gate that instructs the recording of data. During a period other than prescribed effective time, the controller supplies a drive signal having the ordinary level to the spin-torque oscillator.
    Type: Application
    Filed: July 26, 2010
    Publication date: June 2, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Toru EZAWA, Shuichi KOJIMA, Masahide KANEGAE, Kenichiro YAMADA, Katsuhiko KOUI, Masayuki TAKAGISHI
  • Patent number: 7492543
    Abstract: Upon recording, a clearance control unit performs preheating by an added control value (BR) of a base heater control value B and an adjustment heater control value R and switches that to value B when it reaches a target sector to perform write. Upon reproduction, preheating is performed by the value (BR) and the value (BR) is maintained when it reaches a target sector to perform read. A correction processing unit detects contact between the head and a medium surface while increasing the value R from a predetermined initial value Ro, and sets a new calculated base heater control value B, and value Ro as the adjustment heater control value R. Write assist adjustment in which the measured adjustment heater control value R is adjusted to a heater control value that improves characteristic deterioration immediately after recording is started wherein preheating is switched to write heating is performed.
    Type: Grant
    Filed: August 24, 2007
    Date of Patent: February 17, 2009
    Assignee: Fujitsu Limited
    Inventors: Nobuyuki Mitsunaga, Masahide Kanegae, Hiroyuki Tanaka, Isamu Tomita, Masao Kondo
  • Publication number: 20090027800
    Abstract: According to an aspect of an embodiment, a storage apparatus includes a judgment unit which judges the clearance between a head and a recording medium. A mode switcher switches from a regular write mode in which data is written on the medium to a write verification mode in which error is checked by reading the data immediately after writing on the medium, where the judgment unit detects a clearance change. A heater control value adjustor corrects for errors detected in the write verification mode by changing a prescribed heater control value for the heater by executing write verifications. An access processor controls the clearance between the head and the medium by heating the head according to the adjusted heater control value, to compensate for operational variables such as low atmospheric pressure.
    Type: Application
    Filed: July 24, 2008
    Publication date: January 29, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Tohru IWAMOTO, Masahide KANEGAE
  • Patent number: 7463438
    Abstract: An information storage apparatus that records servo information and user data on a recording face of a recording medium wherein a track density measuring unit measures the optimal track density for a recording face corresponding to each head targeting a storage medium on which the servo information has not yet been recorded and a recording density measuring unit measures the optimal linear density for each recording face. A servo frame writing unit writes the servo information varying a track pitch to a track pitch corresponding to the optimal track density measured by the track density measuring unit and a recording frequency to a recording frequency corresponding to the optimal linear density measured by the linear density measuring unit, for each head.
    Type: Grant
    Filed: January 26, 2005
    Date of Patent: December 9, 2008
    Assignee: Fujitsu Limited
    Inventors: Tatsuhiko Kosugi, Masahide Kanegae
  • Publication number: 20080100950
    Abstract: Upon recording, a clearance control unit performs preheating by an added control value (B+R) of a base heater control value B and an adjustment heater control value R and switches that to merely the base heater control value B when it reaches a target sector so as to perform write. Upon reproduction, preheating is performed by the added control value (B+R), and the added control value (B+R) is maintained when it reaches a target sector so as to perform read. A correction processing unit 46 detects contact (touchdown) between the head and a medium surface while gradually increasing the adjustment heater control value R from a predetermined initial value Ro, sets a value, which is obtained by subtracting a heater control value Sp converted from a minimum clearance and the initial value Ro from a contact heater control value Rtd, as the base heater control value B, and sets the initial value Ro as the adjustment heater control value R.
    Type: Application
    Filed: August 24, 2007
    Publication date: May 1, 2008
    Applicant: Fujitsu Limited
    Inventors: Nobuyuki Mitsunaga, Masahide Kanegae, Hiroyuki Tanaka, Isamu Tomita, Masao Kondo
  • Publication number: 20070233411
    Abstract: In an electronic device having an interface circuit which operates using a fast clock source, frequency deviation of the clock source is inspected in the mounted state. The clock pulses of the fast clock source are counted in synchronization with an electronic device serving as reference, and the result is checked; or, alignment data of transfer data and overflow/underflow of the FIFO buffer are utilized; or, the count values of an internal counter and a fast clock counter are utilized, to check for frequency deviation of the fast clock source. In the state of being mounted in the device, tests can be performed of the clock sources of all units.
    Type: Application
    Filed: July 17, 2006
    Publication date: October 4, 2007
    Applicant: FUJITSU LIMITED
    Inventors: Hiroyuki Suto, Masahide Kanegae, Osamu Kawashima, Michihiko Umeda
  • Patent number: 7272527
    Abstract: In an electronic device having an interface circuit which operates using a fast clock source, frequency deviation of the clock source is inspected in the mounted state. The clock pulses of the fast clock source are counted in synchronization with an electronic device serving as reference, and the result is checked; or, alignment data of transfer data and overflow/underflow of the FIFO buffer are utilized; or, the count values of an internal counter and a fast clock counter are utilized, to check for frequency deviation of the fast clock source. In the state of being mounted in the device, tests can be performed of the clock sources of all units.
    Type: Grant
    Filed: July 17, 2006
    Date of Patent: September 18, 2007
    Assignee: Fujitsu Limited
    Inventors: Hiroyuki Suto, Masahide Kanegae, Osamu Kawashima, Michihiko Umeda
  • Publication number: 20060082918
    Abstract: An information storage apparatus that records servo information and user data on a recording face of a recording medium wherein a track density measuring unit measures the optimal track density for a recording face corresponding to each head targeting a storage medium on which the servo information has not yet been recorded and a recording density measuring unit measures the optimal linear density for each recording face. A servo frame writing unit writes the servo information varying a track pitch to a track pitch corresponding to the optimal track density measured by the track density measuring unit and a recording frequency to a recording frequency corresponding to the optimal linear density measured by the linear density measuring unit, for each head.
    Type: Application
    Filed: January 25, 2005
    Publication date: April 20, 2006
    Inventors: Tatsuhiko Kosugi, Masahide Kanegae
  • Patent number: 6130793
    Abstract: A thermal asperity detection method includes the steps of (a) converting an analog signal reproduced from a magnetic recording medium into a digital signal using an analog-to-digital converter, (b) detecting thermal asperity based on the digital signal, and (c) automatically recognizing and managing detection of the thermal asperity by the step (b) by firmware.
    Type: Grant
    Filed: March 21, 1997
    Date of Patent: October 10, 2000
    Assignee: Fujitsu Limited
    Inventors: Hideki Ohmori, Masahide Kanegae, Isamu Tomita
  • Patent number: 6124998
    Abstract: A recording unit is provided, to which a write current is supplied in accordance with information to be stored. The recording unit records the information in a recording medium in accordance with the write current. A temperature detecting unit detects an ambient temperature of the recording medium. A timer monitors time for the temperature detecting unit to detect the ambient temperature of the recording medium at predetermined times. A write-current setting unit sets the write current for the ambient temperature of the recording medium detected by the temperature detecting unit, each time when the temperature detecting unit detects the ambient temperature of the recording medium, the time being obtained from the timer.
    Type: Grant
    Filed: December 31, 1997
    Date of Patent: September 26, 2000
    Assignee: Fujitsu Limited
    Inventor: Masahide Kanegae
  • Patent number: 6021025
    Abstract: An actuator for moving heads in a disk unit having heads for reading or writing data from or on recording surfaces of disks driven to rotate, an actuator having arms for supporting the heads, a main FPC board having one end thereof supported by the actuator and the other end thereof supported by a body of the disk unit, and relay FPC boards placed along the arms of the actuator, which can realize a compact and thin size, resistive to noise, and permitting a reduction in manufacturing cost. A printed-circuit board is supported by an actuator, is electrically connected to a circuit unit in a body of a disk unit via a main FPC board, and is electrically connected to heads via relay FPC boards. Integrated circuits are mounted on the printed-circuit board.
    Type: Grant
    Filed: March 26, 1997
    Date of Patent: February 1, 2000
    Assignee: Fujitsu Limited
    Inventors: Yukihiro Komura, Yoshiaki Nagasawa, Masahide Kanegae, Hajime Miura
  • Patent number: 6002538
    Abstract: Disclosed is a PRML regenerating apparatus for regenerating a signal read by a head from a storage medium. This PRML regenerating apparatus has a waveform equalizing circuit for waveform-equalizing the read signal, a maximum-likelihood decoder for maximum-likelihood-decoding, after obtaining a determination value by comparing the equalized output with upper and lower slice levels, this determination value and a control circuit for setting variable a distance between the upper slice level and the lower slice level of the maximum-likelihood decoder. The distance between the upper and lower slice levels can be thereby set variable in accordance with an equalization characteristic. A ternary determination circuit of the maximum-likelihood decoder is constructed of a memory for storing a correspondence table of the equalized output and the upper or lower slice level versus the determination result and the next upper or lower slice level.
    Type: Grant
    Filed: March 8, 1995
    Date of Patent: December 14, 1999
    Assignee: Fujitsu, Ltd.
    Inventors: Masahide Kanegae, Katutoshi Asai, Yoshihiro Hashimura, Hideki Ohmori, Masahito Iwatsubo, Masao Kondou, Tomoki Sugaya, Hiroyuki Tanaka