Patents by Inventor Masayuki Kurita

Masayuki Kurita 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: 7480115
    Abstract: Embodiment of the invention improve the productivity of a magnetic disk drive that controls the flying height of a magnetic head by use of a heater. According to an embodiment, in a method for manufacturing a magnetic disk drive that writes/reads information to/from a magnetic disk medium by use of a magnetic head including a heater adapted to control the flying height, the read and write performance of the magnetic head is tested; a heating condition used at the time of heating by the heater is determined on the basis of the test results; and a control parameter that specifies the amount of heating by the heater in the determined heating condition is determined.
    Type: Grant
    Filed: July 26, 2006
    Date of Patent: January 20, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Ono Hiroyuki, Mike Suk, Hideaki Tanaka, Masayuki Kurita
  • Patent number: 7457073
    Abstract: Embodiments in accordance with the present invention allow a magnetic disk drive to achieve noise reduction and low power consumption through rotation at a low speed and a high transfer rate through rotation at a high speed while allowing reliability to be maintained and achieving an improved recording density. An embodiment of a magnetic disk drive in accordance with the present invention includes, a magnetic disk medium driven at a plurality of rotational speeds, a magnetic head for recording and reproducing data in and from the magnetic disk medium, a heater for controlling a flying height of the magnetic head, and a control unit for controlling the current to the heater, and in that the control unit controls the current to the heater. The control unit controls the current to the heater according to the plurality of rotational speeds.
    Type: Grant
    Filed: February 14, 2007
    Date of Patent: November 25, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masayuki Kurita, Yukie Hiratsuka, Mikio Tokuyama, Hideaki Tanaka
  • Publication number: 20080273262
    Abstract: Embodiments of the present invention help to improve the cost, mountability, and reliability of a magnetic disk drive that regulates a fly height of a magnetic head slider correspondingly to the operating altitude of the drive by using an air pressure sensor and a heater. According to one embodiment, a preamplifier is a semiconductor chip formed by three-dimensionally laminating thin film circuits on a bulk silicon wafer. An air pressure sensor is integrally formed on the semiconductor chip through a semiconductor process. The air pressure sensor is configured to include an isolating cavity, a diaphragm that deflecting in response to a change in a pressure difference between the isolating cavity and the outside, and lower and upper electrodes and for detecting variation in electrostatic capacitance. The preamplifier including the air pressure sensor integrally formed therein is attached to a flexible printed cable (FPC) to oppose the FPC.
    Type: Application
    Filed: January 4, 2008
    Publication date: November 6, 2008
    Applicant: Hitachi Global Storage Technologies Inc. Netherlands B.V.
    Inventors: Masayuki Kurita, Masashi Murai, Hideaki Tanaka, Noriaki Satoh, Hiroshi Fukuda, Tsukasa Fujimori
  • Publication number: 20080247079
    Abstract: Embodiments in accordance with the present invention reduce the number of errors caused by the aged deterioration of a heater for adjusting the clearance between a head and a disk. According to one embodiment, a thermal fly height control (TFC) controller executes the measurement of a resistance value of a heater in a predetermined timing. The TFC controller judges whether or not the measured resistance value falls within a predetermined reference range. If the measured resistance value falls within the reference range, the processing ends without performing any other processing. If the measured resistance value goes out of the reference range, the TFC controller executes error handling processing in response to a resistance failure. As one of the error handling processing, the TFC controller notifies the host that the abnormality (resistance failure) has been detected in the resistance value of the TFC heater.
    Type: Application
    Filed: April 25, 2007
    Publication date: October 9, 2008
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Noriaki Satoh, Toyomi Ohsawa, Yumi Nagano, Kouji Miyake, Yoshiaki Uji, Masayuki Kurita
  • Publication number: 20080212236
    Abstract: A suspension having a magnetic head assembly 1 mounted thereon is provided, wherein the magnetic head assembly comprises: a write head 1-2; a read head 1-1; and a resistive heating element 1-3 for controlling the flying heights of the magnetic heads, wherein the wires HTx and GTx for the resistive heating element is disposed such that they sandwich the wires RxX and RxY for the read head. The wires for the resistive heating element may be disposed between the wires for the write head and the wires for the read head. Furthermore, the waveform of the current or voltage to the resistive heating element has a time constant of 1 ?sec or more, the resistive heating element having wires disposed near the wires of the read head.
    Type: Application
    Filed: April 4, 2008
    Publication date: September 4, 2008
    Applicant: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Naoki Satoh, Masayuki Kurita, Mikio Tokuyama, Junguo Xu
  • Publication number: 20080192379
    Abstract: Embodiments of the present invention provide a process that monitors a magnetic playback signal while gradually increasing an electricity supply amount for a heater to thereby determine contact between a magnetic head slider and a magnetic disk medium. According to one embodiment, after components for configuring a magnetic recording/playback portion are assembled into a housing, magnetic information is played back on a specific track of a magnetic disk medium by using a playback element while gradually increasing an electricity supply amount for a heater of a magnetic head slider. An amplitude of a playback signal is measured at a plurality of portions along a circumferential direction of the track. Contact between the magnetic head slider and the magnetic disk medium is detected in accordance with an increase in variation in the measured amplitude.
    Type: Application
    Filed: January 24, 2008
    Publication date: August 14, 2008
    Inventors: Masayuki Kurita, Hideaki Tanaka, Noriaki Satoh, Toyomi Ohsawa, Toshiya Shiramatsu, Atsushi Yatagai, Satoshi Ohki, Hiroshi Ide, Hidekazu Kohira, Takehiko Hamaguchi
  • Patent number: 7375913
    Abstract: A suspension having a magnetic head assembly 1 mounted thereon is provided, wherein the magnetic head assembly comprises: a write head 1-2; a read head 1-1; and a resistive heating element 1-3 for controlling the flying heights of the magnetic heads, wherein the wires HTx and GTx for the resistive heating element is disposed such that they sandwich the wires RxX and RxY for the read head. The wires for the resistive heating element may be disposed between the wires for the write head and the wires for the read head. Furthermore, the waveform of the current or voltage to the resistive heating element has a time constant of 1 ?sec or more, the resistive heating element having wires disposed near the wires of the read head.
    Type: Grant
    Filed: June 27, 2006
    Date of Patent: May 20, 2008
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Naoki Satoh, Masayuki Kurita, Mikio Tokuyama, Junguo Xu
  • Patent number: 7362544
    Abstract: A thermal flying height adjustment slider capable of being mounted on a small-sized thin film magnetic head slider is provided wherein terminals of an energizer serving as a heater prevent corrosion of pole pieces and the number of terminals is reduced. In one embodiment, one of terminals of the energizer serving as the heater is electrically connected to the lower pole piece, so that a relay terminal for a heating device is used also as the terminal for preventing the corrosion of pole pieces.
    Type: Grant
    Filed: September 17, 2004
    Date of Patent: April 22, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Toshiya Shiramatsu, Masayuki Kurita, Mikio Tokuyama, Hidekazu Kohira, Masahiko Soga
  • Publication number: 20070247758
    Abstract: According to embodiments of the present invention, a magnetic head slider provided with a heater disposed near a read element to adjust flying height, is required to increase a thermal protrusion by heat generated by the heater without increasing a thermal protrusion attributable to heat generated by a recording current or environmental temperature. A magnetic head slider includes a thin-film head unit including a read element, a heater having a thin heating line extended above and below the read element, a write element, and an insulating layer of alumina (Al2O3) or the like insulating those components. The thin heating line of the heater is formed from a thin resistive film of NiCr or the like. The thin heating line of the heater is extended above and below the read element so as to meander in a zigzag shape in a direction perpendicular to the device forming surface. The thin heating line has a thickness between about 0.1 and 0.
    Type: Application
    Filed: April 19, 2007
    Publication date: October 25, 2007
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masayuki Kurita, Toshiya Shiramatsu, Masanori Tanabe, Takayoshi Ohtsu
  • Publication number: 20070236836
    Abstract: Embodiments in accordance with the present invention provide a thin-film head formed on an AlTiC substrate of a magnetic head slider. A thin-film head include a write element, a read element, a heater, an alumina insulating film that separates the elements and heater from one another, electric wiring films leading to the respective elements, and an alumina protective insulating film that protects all the layered films. For this configuration, in order to maximize a change in a flying height caused by heat dissipated from the heater and minimize a change in the flying height caused by heat dissipation derived from a recording current, the write element is first formed on the AlTiC substrate and the read element is formed on the write element. An adiabatic layer made of a material exhibiting low thermal conductivity may be formed between the write element and the read element and heater.
    Type: Application
    Filed: April 6, 2007
    Publication date: October 11, 2007
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masayuki Kurita, Toshiya Shiramatsu, Kazuhiro Nakamoto
  • Patent number: 7278902
    Abstract: Various embodiments of the present invention pertain to enabling location specific burnishing of a disk. According to one embodiment, the smoothness of a disk is evaluated by gliding over a disk to determine if there is an asperity on the disk. If there is an asperity on the disk, a location of the asperity is stored to enable location specific burnishing of the disk.
    Type: Grant
    Filed: March 14, 2006
    Date of Patent: October 9, 2007
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Masayuki Kurita, Remmelt Pit, Shozo Saegusa, Toshiya Shiramatsu, Mike Suk, Hideaki Tanaka
  • Publication number: 20070214874
    Abstract: Various embodiments of the present invention pertain to enabling location specific burnishing of a disk. According to one embodiment, the smoothness of a disk is evaluated by gliding over a disk to determine if there is an asperity on the disk. If there is an asperity on the disk, a location of the asperity is stored to enable location specific burnishing of the disk.
    Type: Application
    Filed: March 14, 2006
    Publication date: September 20, 2007
    Inventors: Masayuki Kurita, Remmelt Pit, Shozo Saegusa, Toshiya Shiramatsu, Mike Suk, Hideaki Tanaka
  • Publication number: 20070188908
    Abstract: Embodiments in accordance with the present invention allow a magnetic disk drive to achieve noise reduction and low power consumption through rotation at a low speed and a high transfer rate through rotation at a high speed while allowing reliability to be maintained and achieving an improved recording density. An embodiment of a magnetic disk drive in accordance with the present invention includes, a magnetic disk medium driven at a plurality of rotational speeds, a magnetic head for recording and reproducing data in and from the magnetic disk medium, a heater for controlling a flying height of the magnetic head, and a control unit for controlling the current to the heater, and in that the control unit controls the current to the heater. The control unit controls the current to the heater according to the plurality of rotational speeds.
    Type: Application
    Filed: February 14, 2007
    Publication date: August 16, 2007
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masayuki Kurita, Yukie Hiratsuka, Mikio Tokuyama, Hideaki Tanaka
  • Patent number: 7209309
    Abstract: A magnetic disk apparatus includes a rotation mechanism for driving a magnetic disk, a magnetic head slider being floated in close proximity to a surface of the magnetic disk, a recording/reproduction element for performing recording and playback of information, a drive unit for causing a distance between the record/reproduction element and the magnetic disk to change, and an arrangement to effect position determination of the magnetic head slider, wherein the apparatus has a detection unit for permitting the drive unit to gradually reduce the distance between the record/reproduction element and the magnetic disk and for detecting occurrence of contact therebetween, and a control unit for controlling the drive unit in such a way as to cause, the record/reproduction element to shift in position by a fixed amount to thereby let the distance between this element and magnetic disk increase accordingly.
    Type: Grant
    Filed: August 18, 2004
    Date of Patent: April 24, 2007
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Masayuki Kurita, Masaaki Matsumoto, Yuuichi Ootani, Yoshihiko Miyake, Shinsuke Higuchi, Hideaki Tanaka, Junguo Xu
  • Publication number: 20070070550
    Abstract: A disk apparatus including: a head slider for being floated above a disk; a record/reproduction element provided at the head slider for recording and/or reproducing information on and/or from the disk; a displacer for shifting the record/reproduction element to approach closer to, or retreat farther away from, the disk; and a controller for controlling the displacer to shift the record/reproduction element in a direction to retreat rather from the disk, if the record/reproduction element has contacted the disk.
    Type: Application
    Filed: November 30, 2006
    Publication date: March 29, 2007
    Inventors: Masayuki Kurita, Masaaki Matsumoto, Yuuichi Ootani, Yoshihiko Miyake, Shinsuke Higuchi, Hideaki Tanaka, Junguo Xu
  • Publication number: 20070064344
    Abstract: Embodiments of the invention reduce the TPR (thermal protrusion phenomenon) of a perpendicular magnetic write head caused by a coil current and a static temperature. In one embodiment, SiO2 having a low coefficient of thermal expansion and high workability is used as a coil insulator. SiO2 is arranged at a position away from the air bearing surface and the air bearing surface is made of alumina, making slider processing easy.
    Type: Application
    Filed: September 11, 2006
    Publication date: March 22, 2007
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kimitoshi Etoh, Hisako Takei, Masayuki Kurita, Yuji Kumazawa
  • Publication number: 20070030593
    Abstract: Embodiment of the invention improve the productivity of a magnetic disk drive that controls the flying height of a magnetic head by use of a heater. According to an embodiment, in a method for manufacturing a magnetic disk drive that writes/reads information to/from a magnetic disk medium by use of a magnetic head including a heater adapted to control the flying height, the read and write performance of the magnetic head is tested; a heating condition used at the time of heating by the heater is determined on the basis of the test results; and a control parameter that specifies the amount of heating by the heater in the determined heating condition is determined.
    Type: Application
    Filed: July 26, 2006
    Publication date: February 8, 2007
    Applicant: Hitachi Global Storage Technologies Netherlands B.V
    Inventors: Ono Hiroyuki, Mike Suk, Hideaki Tanaka, Masayuki Kurita
  • Patent number: 7153192
    Abstract: A method for selectively sensing and removing asperities from the surface of hard disk drive media is disclosed. A thermally controlled flying height burnish slider is flown on a test stand with its thermal flying height control deactivated. The burnish slider flies at a nominal flying height over the surface of the media to remove any existing loose particles from the surface. A glide slider coupled to a PZT sensor is then flown over the surface of the media, the PZT sensor head mapping locations of any asperities on the surface of the media. The thermal flying height controlled burnish slider is next flown over the surface of the media with the thermal flying height control activated. The thermal flying height control is actuated when a mapped location of an asperity on the surface is proximate to the burnish slider, causing the burnish slider to protrude, wearing off the asperity.
    Type: Grant
    Filed: October 18, 2005
    Date of Patent: December 26, 2006
    Assignee: Hitachi Global Storage Netherlands B.V.
    Inventors: Masayuki Kurita, Remmelt Pit, Shozo Saegusa, Toshiya Shiramatsu, Mike Suk, Hideaki Tanaka
  • Patent number: 7153193
    Abstract: A system for selectively sensing and removing asperities from hard disk drive disk is disclosed. The system includes a test stand supporting the disk, the test stand having at least one suspension for flying over a surface of the disk. The system also includes a glide pad coupled to the at least one suspension for flying over the surface and locating asperities. A PZT sensor is coupled to the glide pad for sensing and mapping asperities on the surface of the disk. A burnish pad is coupled to the at least one suspension for wearing-away sensed and mapped asperities on the surface of the disk and a thermal fly height controller is coupled to the burnish pad for protruding the burnish pad when it is proximate to one of the mapped asperities for facilitating the wearing-away of the mapped asperity.
    Type: Grant
    Filed: October 18, 2005
    Date of Patent: December 26, 2006
    Assignee: Hitachi Global Storage Netherlands B.V.
    Inventors: Masayuki Kurita, Remmelt Pit, Shozo Saegusa, Toshiya Shiramatsu, Mike Suk, Hideaki Tanaka
  • Publication number: 20060279878
    Abstract: In a magnetic disk unit, the flying height margin of a magnetic recording element part during recording is reduced, whereby improvement in recording density and increase in capacity or decrease in size of the unit is realized. In one embodiment, a magnetic disk unit has a magnetic disk arranged in a freely rotational manner and a magnetic head slider disposed to face a surface of the magnetic disk, and generates air flow between the magnetic disk and the magnetic head slider for flying, and records data using a magnetic recording element. The magnetic head slider has a slider substrate part and a thin-film head part formed on the slider substrate part using a thin-film process. The thin-film head part has an insulating member, a magnetic recording element provided in the insulating member, and a heat radiation member for radiating heat generated by the magnetic recording element from lateral regions of the magnetic recording element to the slider substrate part.
    Type: Application
    Filed: June 7, 2006
    Publication date: December 14, 2006
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Toshiya Shiramatsu, Masayuki Kurita, Mikio Tokuyama