Patents by Inventor Yohji Maruyama

Yohji Maruyama 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: 9672846
    Abstract: The MAMR head comprises a main pole, a spin torque oscillator (STO) positioned over the main pole, and write coils coupled to the main pole. The STO generates a high frequency magnetic field on a magnetic medium. The controller is configured to supply the STO with first bias current at a first bias current level, and further supply the STO with second bias current at a second bias current level. The controller is further configured to time the second bias current to coincide with an electrical current overshoot in the write coils.
    Type: Grant
    Filed: June 21, 2016
    Date of Patent: June 6, 2017
    Assignee: Western Digital Technologies, Inc.
    Inventors: Hideaki Tanaka, Katsuro Watanabe, Shigeru Tadokoro, Wataru Kimura, Yohji Maruyama
  • Patent number: 9330687
    Abstract: A magnetic recording head for microwave-assisted magnetic recording is disclosed. In one embodiment, a magnetic recording head is for applying a magnetic field from a main pole of said magnetic recording head for recording data to a disk. Further comprising a spin torque oscillator adjacent to said magnetic recording head and is for generating a high-frequency magnetic field at a stable frequency and amplitude. Further comprising a capacitor connected to an upper electrode of said spin torque oscillator via a first resistor and a lower electrode of said spin torque oscillator via a second resistor.
    Type: Grant
    Filed: October 16, 2013
    Date of Patent: May 3, 2016
    Assignee: HGST Netherlands B.V.
    Inventors: Katsuro Watanabe, Yohji Maruyama
  • Patent number: 9230573
    Abstract: A magnetic write head having a write pole with a tapered trailing edge and a magnetic oscillator formed on the trailing edge of the write pole. The magnetic oscillator is sandwiched between the magnetic write pole and a trailing magnetic shield. The write head also includes a non-magnetic, electrically conductive bump structure located over a back portion of the magnetic oscillator between the magnetic oscillator and the trailing magnetic shield. The presence of the non-magnetic, electrically conductive bump structure causes electrons to properly flow through the magnetic oscillator in a direction that is generally perpendicular to the plane of the magnetic oscillator, even when the magnetic oscillator is formed on an inclined plane on the tapered trailing edge of the write pole. This thereby ensures optimal performance of the magnetic oscillator.
    Type: Grant
    Filed: January 21, 2015
    Date of Patent: January 5, 2016
    Assignee: HGST Netherlands B.V.
    Inventors: Kimitoshi Etoh, Kenji Sugiura, Mikito Sugiyama, Yohji Maruyama, Kazuhiko Hosomi, Katsuro Watanabe
  • Patent number: 9230566
    Abstract: Embodiments disclosed herein generally relate to a perpendicular magnetic recording head for recording magnetic information and a magnetic recording device employing the magnetic head. The magnetic recording head comprises at least one thin shield region having a high coercive force and a magnetization direction oriented towards the right when viewed from the MFS with the leading side on bottom and the trailing side on top, and at least one thick shield region having a low coercive force. The thin shield region surrounds a main pole, and the thick shield region partially surrounds the thin shield region. The magnetic recording head is able to reduce FTI by controlling the magnetization direction of the shield layers.
    Type: Grant
    Filed: October 29, 2014
    Date of Patent: January 5, 2016
    Assignee: HGST Netherlands B.V.
    Inventors: Tadayuki Iwakura, Yohji Maruyama, Wataru Kimura, Shigeru Tadokoro
  • Patent number: 9142227
    Abstract: A microwave-assisted magnetic recording (MAMR) write head includes a yoke structure with a main pole, a flux return pole, and a trailing magnetic shield. The main pole includes a write pole with a tip at the disk-facing surface, a sub pole with an end recessed from the disk-facing surface and an electrically insulating layer between the write pole and the sub pole. The spin-torque oscillator (STO) is located at the disk-facing surface between the trailing shield and the write pole tip. The insulating layer assures that the STO current is not shorted between the return pole and the write pole. The insulating layer between the write pole and the sub pole increases the area of the junction between the return pole and write pole, which reduces the magnetic reluctance of the yoke structure.
    Type: Grant
    Filed: September 8, 2014
    Date of Patent: September 22, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: Kimitoshi Etoh, Masahiko Hatatani, Kazuhiko Hosomi, Yohji Maruyama, Kenji Sugiura, Mikito Sugiyama
  • Patent number: 9099127
    Abstract: A magnetic read head and associated circuitry for reducing side track noise and decreasing read width, thereby providing increased data density. The magnetic read head includes first and second sensor elements that are aligned with one another in a data track direction, with the first sensor element being wider than the second sensor element. Electrical circuitry is connected with the read head in such a manner as to read a first signal from the first sensor element and a second signal from a second sensor element. Because the second sensor element is wider than the first sensor element, it will read more side signal noise from adjacent data tracks than will the second sensor element. The circuitry connected with the first and second sensor element detects and distinguishes the side signal noise and separates it out from the data signal, based sensor width difference and location difference.
    Type: Grant
    Filed: May 30, 2014
    Date of Patent: August 4, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: Taku Shintani, Yohji Maruyama, Kouichi Nishioka, Masafumi Mochizuki
  • Patent number: 9076462
    Abstract: In one embodiment, a magnetic head includes a main pole configured to write data to a magnetic medium using a magnetic field, a return pole positioned above the main pole at a media-facing surface of the magnetic head, the return pole being configured to return magnetic flux from the main pole after it has exited a magnetic medium, and a coil configured to produce magnetic flux in the main pole, the coil being positioned below the return pole, wherein a film thickness of a first turn of the coil on a media-facing surface side thereof is less than a film thickness of a second turn of the coil. Other magnetic heads having a shortened magnetic circuit length and methods of production thereof are presented in additional embodiments.
    Type: Grant
    Filed: December 3, 2013
    Date of Patent: July 7, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: Kimitoshi Etoh, Kazuhiko Hosomi, Mikito Sugiyama, Yohji Maruyama
  • Publication number: 20150154987
    Abstract: In one embodiment, a magnetic head includes a main pole configured to write data to a magnetic medium using a magnetic field, a return pole positioned above the main pole at a media-facing surface of the magnetic head, the return pole being configured to return magnetic flux from the main pole after it has exited a magnetic medium, and a coil configured to produce magnetic flux in the main pole, the coil being positioned below the return pole, wherein a film thickness of a first turn of the coil on a media-facing surface side thereof is less than a film thickness of a second turn of the coil. Other magnetic heads having a shortened magnetic circuit length and methods of production thereof are presented in additional embodiments.
    Type: Application
    Filed: December 3, 2013
    Publication date: June 4, 2015
    Applicant: HGST NETHERLANDS B.V.
    Inventors: Kimitoshi Etoh, Kazuhiko Hosomi, Mikito Sugiyama, Yohji Maruyama
  • Publication number: 20150103437
    Abstract: A magnetic recording head for microwave-assisted magnetic recording is disclosed. In one embodiment, a magnetic recording head is for applying a magnetic field from a main pole of said magnetic recording head for recording data to a disk. Further comprising a spin torque oscillator adjacent to said magnetic recording head and is for generating a high-frequency magnetic field at a stable frequency and amplitude. Further comprising a capacitor connected to an upper electrode of said spin torque oscillator via a first resistor and a lower electrode of said spin torque oscillator via a second resistor.
    Type: Application
    Filed: October 16, 2013
    Publication date: April 16, 2015
    Applicant: HGST Netherlands B.V.
    Inventors: Katsuro Watanabe, Yohji Maruyama
  • Patent number: 8786986
    Abstract: A head-slider. The head-slider includes a slider, and a thin-film magnetic-recording head. The thin-film magnetic-recording head includes: a read element; a write element; a non-magnetic insulating protective layer disposed around both read and write elements; a resist disposed at a position further away from an air-bearing surface than the read element; and, a hard-material member including a material selected from the group consisting of silicon carbide and tungsten, which is disposed at a position further away from the air-bearing surface than the read element and the write element. Both an end of the resist and an end of the hard-material member overlap the write element when viewed in a stacking direction. A ratio of a distance from the air-bearing surface to a deepest end of the hard-material member to a distance from the air-bearing surface to a deepest end of the resist is at least 0.9.
    Type: Grant
    Filed: December 18, 2009
    Date of Patent: July 22, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Shigeo Fujita, Masahiko Soga, Hideaki Tanaka, Yuji Ueda, Tomohiro Okada, Takayoshi Ohtsu, Wataru Kimura, Yohji Maruyama
  • Patent number: 8570683
    Abstract: In one embodiment, a perpendicular magnetic head includes a main magnetic pole, a side shield disposed on both sides of the main magnetic pole in a track width direction, the side shield including a material having a saturation magnetic flux density of no greater than about 1.0 T, and a trailing shield disposed on a trailing side of the main magnetic pole, wherein the trailing shield and the side shield are physically separated from one another. In another embodiment, the side shield includes a first magnetic film, and the trailing shield includes a second magnetic film, wherein a magnetic permeability of the first magnetic film is lower than a magnetic permeability of the second magnetic film.
    Type: Grant
    Filed: June 24, 2011
    Date of Patent: October 29, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Yusuke Takahashi, Hiromi Shiina, Kazue Kudo, Yohji Maruyama, Kaori Suzuki
  • Patent number: 8542462
    Abstract: According to one embodiment, a perpendicular magnetic recording head includes a main magnetic pole having a trailing side and two lateral sides, a magnetic shield near the trailing side and both lateral sides of the main magnetic pole, the magnetic shield comprising: a first soft magnetic film with a relatively high saturation flux density positioned facing depthwise from a floating surface side thereof, a second soft magnetic film with a relatively low saturation flux density, and a first non-magnetic film. The head also includes a non-magnetic film interposed between the magnetic shield and the main magnetic pole, a first magnetic film magnetically coupled to the magnetic shield and the main magnetic pole on a side opposite a floating surface side thereof, and a coil surrounding a magnetic circuit, the magnetic circuit comprising the main magnetic pole and the first magnetic film. Other systems and methods are also described.
    Type: Grant
    Filed: June 30, 2010
    Date of Patent: September 24, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Yohji Maruyama, Tadayuki Iwakura, Tetsuya Okai, Hiromi Shiina, Kazue Kudo
  • Patent number: 8537493
    Abstract: According to one embodiment, a magnetic head for perpendicular recording includes a main pole, a first soft magnetic film disposed on a trailing side of the main pole, and a first nonmagnetic film interposed between the main pole and the first soft magnetic film. A thickness of the main pole is increased in a depth direction from an air bearing surface using an inclination, and a thickness of the first nonmagnetic film increases in the depth direction from the air bearing surface. In another embodiment, an angle from a horizontal plane of an upper surface of the first nonmagnetic film is greater than an angle from a horizontal plane of a lower surface of the first nonmagnetic film in contact with the main pole. Other heads, methods, and systems are described according to more embodiments.
    Type: Grant
    Filed: December 10, 2010
    Date of Patent: September 17, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Kazue Kudo, Hiromi Shiina, Yohji Maruyama, Shouji Tokutake, Tetsuya Okai
  • Patent number: 8477455
    Abstract: A slider comprising a contact sensor element configured to respond to a change in resistance due to a change in temperature, and a shield structure. The shield structure comprises a lower thermal conductivity than the contact sensor element and a greater hardness than the contact sensor element.
    Type: Grant
    Filed: November 16, 2010
    Date of Patent: July 2, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Masaru Furukawa, Yuki Shimizu, Junguo Xu, Yohji Maruyama, Takayoshi Ohtsu, Toshiya Shiramatsu
  • Patent number: 8373940
    Abstract: According to one embodiment, a magnetic head for recording magnetic data by changing the magnetization direction of a magnetic recording layer of a magnetic medium comprises a magnetic pole for generating a magnetic field to change the magnetization direction of the magnetic recording layer, and a facing electrode pair for generating an electromagnetic field and applying energy to the magnetic recording layer to assist the change of the magnetization direction of the magnetic recording layer caused by the magnetic field from the magnetic pole. Other embodiments are also presented.
    Type: Grant
    Filed: August 26, 2009
    Date of Patent: February 12, 2013
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Yohji Maruyama, Nobumasa Nishiyama, Masafumi Mochizuki
  • Patent number: 8351156
    Abstract: A perpendicular magnetic recording head according to one embodiment includes a main pole; first magnetic films arranged on both sides of the main pole in a track width direction via nonmagnetic films; and a second magnetic film arranged on a trailing side of the main pole via a nonmagnetic film; wherein the depths of the first magnetic films from an air bearing surface are smaller than the depth of the second magnetic film from the air bearing surface at least at a periphery of the main pole.
    Type: Grant
    Filed: December 15, 2009
    Date of Patent: January 8, 2013
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kazue Kudo, Hiromi Shiina, Yohji Maruyama, Tetsuya Okai, Gen Oikawa, Shouji Tokutake
  • Publication number: 20120327531
    Abstract: In one embodiment, a perpendicular magnetic head includes a main magnetic pole, a side shield disposed on both sides of the main magnetic pole in a track width direction, the side shield including a material having a saturation magnetic flux density of no greater than about 1.0 T, and a trailing shield disposed on a trailing side of the main magnetic pole, wherein the trailing shield and the side shield are physically separated from one another. In another embodiment, the side shield includes a first magnetic film, and the trailing shield includes a second magnetic film, wherein a magnetic permeability of the first magnetic film is lower than a magnetic permeability of the second magnetic film.
    Type: Application
    Filed: June 24, 2011
    Publication date: December 27, 2012
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Yusuke Takahashi, Hiromi Shiina, Kazue Kudo, Yohji Maruyama, Kaori Suzuki
  • Patent number: 8300358
    Abstract: Embodiments of the present invention help to suppress broadening of a write field of a main pole of a perpendicular recording head and realize high-quality write operation. According to one embodiment, a main pole of a write head extends to an air bearing surface or a medium-facing surface and has an inverted trapezoid in cross-section. First soft magnetic films called side shields are separately disposed through a nonmagnetic film on both sides of the main pole. The air bearing surface side end of the first soft magnetic film is provided to recede from the air bearing surface. The first soft magnetic film and the main pole are formed in the same layer. A second soft magnetic film called a trailing shield is provided above the main pole on the air bearing surface side via a nonmagnetic film.
    Type: Grant
    Filed: February 15, 2008
    Date of Patent: October 30, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Yohji Maruyama, Tadayuki Iwakura, Kimitoshi Etoh, Hiromi Shiina, Kazue Kudo
  • Patent number: 8248732
    Abstract: A head-gimbal assembly. The head-gimbal assembly includes a suspension, a head-slider coupled to the suspension, a magnetic-recording assistance element on the head-slider for applying an electromagnetic wave to a magnetic-recording disk, and a transmission line on the suspension for transmitting signals to the magnetic-recording assistance element. The transmission line includes an electrically conductive line for transmitting the signals, an upper shield placed above the electrically conductive line along the electrically conductive line, a lower shield placed below the electrically conductive line along the electrically conductive line, and a plurality of columns arranged at each of a right side and a left side of the electrically conductive line along the electrically conductive line for connecting the upper shield and the lower shield. The plurality of columns arranged at the right and left sides includes, respectively, a right linear array of columns and a left linear array of columns.
    Type: Grant
    Filed: September 22, 2009
    Date of Patent: August 21, 2012
    Assignee: Hitachi Global Storage Technologies, Netherlands B.V.
    Inventors: Nobumasa Nishiyama, Yohji Maruyama
  • Patent number: 8223458
    Abstract: A magnetic head, according to one embodiment, includes a main magnetic pole having a protruding portion such that a distance from a first side of a trailing edge of the main magnetic pole to a leading edge of the main magnetic pole is different from a distance from a second side of the trailing edge of the main magnetic pole to the leading edge of the main magnetic pole, an auxiliary magnetic pole, and a coil wound around a magnetic circuit, the magnetic circuit including the main magnetic pole and the auxiliary magnetic pole. In another embodiment, a disk drive system includes a magnetic storage medium, at least one magnetic head as described previously for writing to the magnetic medium, a slider for supporting the magnetic head, and a control unit coupled to the magnetic head for controlling operation of the magnetic head. Additional systems and heads are also presented.
    Type: Grant
    Filed: April 8, 2010
    Date of Patent: July 17, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masafumi Mochizuki, Yohji Maruyama, Etoh Kimitoshi