Patents by Inventor Yoshiharu Kasamatsu

Yoshiharu Kasamatsu 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: 8018683
    Abstract: A head slider that can furnish excellent head flying stability and a magnetic recording device having excellent head flying stability are provided. For the head slider, the protective layer is composed of two layers, that is, a lower layer and an upper layer thereon; the ionization potential of the lower layer is made to be smaller than that of the upper layer; and the surface free energy of the upper layer is made to be 45 mN/m or less.
    Type: Grant
    Filed: November 21, 2007
    Date of Patent: September 13, 2011
    Assignee: Fujitsu Limited
    Inventors: Norikazu Nakamura, Hiroshi Chiba, Yoshiharu Kasamatsu, Takayuki Musashi, Yukiko Oshikubo, Tsukasa Itani
  • Publication number: 20100246066
    Abstract: According to one embodiment, a head slider includes an element unit formed by lamination on a substrate, a cut surface formed by cutting the substrate, an air-bearing surface configured to face a recording medium when in flight, a protective layer configured to protect at least the air-bearing surface of the element unit, and a coating layer configured to cover at least the cut surface exclusive of the air-bearing surface of the element unit. An outermost surface of the air-bearing surface is formed of the protective layer in the element unit at the least.
    Type: Application
    Filed: May 28, 2010
    Publication date: September 30, 2010
    Applicant: TOSHIBA STORAGE DEVICE CORPORATION
    Inventors: Yoshiharu KASAMATSU, Takayuki MUSASHI, Keiji WATANABE
  • Patent number: 7697239
    Abstract: A magnetic head used in a lamp load type magnetic disk device is disclosed. The magnetic head includes a head slider having a recording element and/or a reproducing element, and a suspension that supports the head slider. The suspension includes a magnetic head support unit arranged at its tip portion. The magnetic head support unit comes into contact with a lamp unit of the magnetic disk device when at least one of magnetic head loading operations and magnetic head unloading operations are performed and has a surface on which a lubricating layer is formed.
    Type: Grant
    Filed: June 25, 2007
    Date of Patent: April 13, 2010
    Assignee: Toshiba Storage Device Corporation
    Inventors: Takayuki Musashi, Yoshiharu Kasamatsu, Jun Watanabe
  • Patent number: 7511922
    Abstract: A medium-opposed surface of a slider body is opposed to a recording medium. A rail is defined on the medium-opposed surface. A groove is defined on the medium-opposed surface between the trailing end of the rail and the trailing end of the medium-opposed surface. A lubricating agent is forced to flow into the groove based on the meniscus effect. Airflow acting on the medium-opposed surface serves to lead the lubricating agent along the groove to the edge of the medium-opposed surface. The lubricating agent is then blown over from the end of the groove at the edge of the medium-opposed surface. The lubricating agent is in this manner prevented from staying between the trailing end of the rail and the trailing end of the medium-opposed surface. The head slider is thus allowed to keep flying in a stable flying attitude.
    Type: Grant
    Filed: March 10, 2005
    Date of Patent: March 31, 2009
    Assignee: Fujitsu Limited
    Inventors: Takayuki Musashi, Yoshiharu Kasamatsu
  • Patent number: 7501192
    Abstract: A first protection layer is overlaid on the surface of a recording layer in a recording medium. A second protection layer is overlaid on the surface of the recording layer at a position adjacent the first protection layer. The second protection layer has a composition different from that of the first protection layer. The first and second protection layers have different compositions, so that the overall protection layer is allowed to have an unequal property. The second protection layer may have a hardness higher than that of the first protection layer. A higher hardness of the second protection layer serves to avoid damages on the surface of the recording medium rather than the first protection layer. The recording medium can reliably be protected from collision or contact of an object.
    Type: Grant
    Filed: August 17, 2004
    Date of Patent: March 10, 2009
    Assignee: Fujitsu Limited
    Inventors: Takayuki Musashi, Yoshiharu Kasamatsu
  • Publication number: 20080259497
    Abstract: A magnetic recording medium and head slider that can furnish excellent head flying stability, a magnetic recording device having excellent head flying stability, and a method for manufacturing, in a short time, a magnetic recording medium and head slider that can furnish such excellent head flying stability, are provided. For both of the magnetic recording medium and head slider, the protective layers are each composed of two layers, that is, a lower layer and an upper layer thereon; the ionization potential of the lower layer is made to be smaller than that of the upper layer; and the surface free energy of the upper layer is made to be 45 mN/m or less.
    Type: Application
    Filed: November 21, 2007
    Publication date: October 23, 2008
    Applicant: Fujitsu Limited
    Inventors: Norikazu Nakamura, Hiroshi Chiba, Yoshiharu Kasamatsu, Takayuki Musashi, Yukiko Oshikubo, Tsukasa Itani
  • Publication number: 20080124580
    Abstract: A magnetic disc device includes a magnetic disc, a magnetic head and an actuator. A ramp portion is provided for retracting the magnetic head when recording/reproducing operation is not performed. The ramp portion is arranged on a running path of the magnetic head on an external side of the magnetic disc so that a part of the ramp portion protrudes to an upper part of the outer periphery of the magnetic disc. A load-bar lubrication layer is formed on the surface of a load bar provided at the leading edge of the magnetic head. A head lubrication layer is formed on a head-slider plane of a head slider of the magnetic head. The load-bar lubrication layer reduces a dynamic friction coefficient with the ramp portion surface and suppresses occurrence of abrasion power, and the head lubrication layer suppresses adhesion of abrasion powder to the head-slider plane.
    Type: Application
    Filed: June 27, 2007
    Publication date: May 29, 2008
    Applicant: FUJITSU LIMITED
    Inventors: Takayuki Musashi, Yoshiharu Kasamatsu, Hiroshi Chiba, Jun Watanabe
  • Patent number: 7317594
    Abstract: A magnetic recording medium and head slider that can furnish excellent head flying stability, a magnetic recording device having excellent head flying stability, and a method for manufacturing, in a short time, a magnetic recording medium and head slider that can furnish such excellent head flying stability, are provided. For both of the magnetic recording medium and head slider, the protective layers are each composed of two layers, that is, a lower layer and an upper layer thereon; the ionization potential of the lower layer is made to be smaller than that of the upper layer; and the surface free energy of the upper layer is made to be 45 mN/m or less.
    Type: Grant
    Filed: January 31, 2005
    Date of Patent: January 8, 2008
    Assignee: Fujitsu Limited
    Inventors: Norikazu Nakamura, Hiroshi Chiba, Yoshiharu Kasamatsu, Takayuki Musashi, Yukiko Oshikubo, Tsukasa Itani
  • Publication number: 20070253108
    Abstract: A magnetic head used in a lamp load type magnetic disk device is disclosed. The magnetic head includes a head slider having a recording element and/or a reproducing element, and a suspension that supports the head slider. The suspension includes a magnetic head support unit arranged at its tip portion. The magnetic head support unit comes into contact with a lamp unit of the magnetic disk device when at least one of magnetic head loading operations and magnetic head unloading operations are performed and has a surface on which a lubricating layer is formed.
    Type: Application
    Filed: June 25, 2007
    Publication date: November 1, 2007
    Applicant: FUJITSU LIMITED
    Inventors: Takayuki Musashi, Yoshiharu Kasamatsu, Jun Watanabe
  • Patent number: 7259937
    Abstract: A head slider to which little amount of contaminants is adhered, that can form a uniform and flat head lubricant layer surface and that has excellent ultra-low floating properties, as well as a magnetic recording device equipped with the head slider are provided. The head slider is equipped with a head slider lubricant layer having an average film thickness of not more than 2.5 nm, and composed of a water-repellent resin, the lubricant layer being formed on the head slider surface and head slider protection layer surface facing the magnetic recording medium, and the surface tension of the head slider lubricant layer determined by the Fowkes equation is not more than those of the head slider surface and head slider protection layer surface.
    Type: Grant
    Filed: February 8, 2005
    Date of Patent: August 21, 2007
    Assignee: Fujitsu Limited
    Inventors: Hiroshi Chiba, Keiji Watanabe, Yoshiharu Kasamatsu, Takayuki Musashi, Yukiko Oshikubo, Eishin Yamakawa, Takeshi Toukairin, Jun Watanabe, Norikazu Nakamura
  • Publication number: 20070058297
    Abstract: A magnetic head slider comprises a slider body comprising a base portion made of an altic material and an element-forming portion, made of alumina, having formed thereon magnetic conversion elements. Slider-flying rails protruding beyond the surface of the slider body are provided. A first protection film is formed on the surface of the slider body to cover a boundary between the element-forming portion and the base portion to thereby prevent a lubricant of a magnetic disk from depositing on the boundary between the base portion and the element-forming portion. Second protection films are formed on the surfaces of the slider-flying rails to protect the magnetic conversion elements from being corroded and damaged. Further, when pneumatic bearings are provided on the slider-flying rails, third protection films are formed on the surfaces of the pneumatic bearings.
    Type: Application
    Filed: November 13, 2006
    Publication date: March 15, 2007
    Applicant: FUJITSU LIMITED
    Inventors: Yoshiharu Kasamatsu, Susumu Yoshida, Takayuki Musashi
  • Patent number: 7154710
    Abstract: A magnetic head slider comprises a slider body comprising a base portion made of an altic material and an element-forming portion, made of alumina, having formed thereon magnetic conversion elements. Slider-flying rails protruding beyond the surface of the slider body are provided. A first protection film is formed on the surface of the slider body to cover a boundary between the element-forming portion and the base portion to thereby prevent a lubricant of a magnetic disk from depositing on the boundary between the base portion and the element-forming portion. Second protection films are formed on the surfaces of the slider-flying rails to protect the magnetic conversion elements from being corroded and damaged. Further, when pneumatic bearings are provided on the slider-flying rails, third protection films are formed on the surfaces of the pneumatic bearings.
    Type: Grant
    Filed: May 12, 2005
    Date of Patent: December 26, 2006
    Assignee: Fujitsu Limited
    Inventors: Yoshiharu Kasamatsu, Susumu Yoshida, Takayuki Musashi
  • Publication number: 20060221502
    Abstract: A magnetic head includes a head slider configured to float above a recording medium and having an element part for recording to and reproducing from the recording medium, the element part being situated on a medium facing surface facing to the recording medium. The medium facing surface has a first air bearing surface situated in a vicinity of a side of an air flow-out end. The medium facing surface has a rear rail having the element part situated at the side of the air flow-out end of the first air bearing surface. The first air bearing surface is covered with a lubricating layer made of water repellent resin and has an average surface roughness larger than an average surface roughness of a surface of the element part.
    Type: Application
    Filed: June 22, 2005
    Publication date: October 5, 2006
    Applicant: FUJITSU LIMITED
    Inventors: Jun Watanabe, Yoshiharu Kasamatsu, Takayuki Musashi, Hiroshi Chiba
  • Publication number: 20060044691
    Abstract: A magnetic recording medium and head slider that can furnish excellent head flying stability, a magnetic recording device having excellent head flying stability, and a method for manufacturing, in a short time, a magnetic recording medium and head slider that can furnish such excellent head flying stability, are provided. For both of the magnetic recording medium and head slider, the protective layers are each composed of two layers, that is, a lower layer and an upper layer thereon; the ionization potential of the lower layer is made to be smaller than that of the upper layer; and the surface free energy of the upper layer is made to be 45 mN/m or less.
    Type: Application
    Filed: January 31, 2005
    Publication date: March 2, 2006
    Inventors: Norikazu Nakamura, Hiroshi Chiba, Yoshiharu Kasamatsu, Takayuki Musashi, Yukiko Oshikubo, Tsukasa Itani
  • Patent number: 6985315
    Abstract: A magnetic disk evaluation apparatus includes an evaluation head for evaluating a magnetic disk, and a support member for supporting the evaluation head. The support member supports the evaluation head in a state where a flying surface of the evaluation head and a surface of a magnetic disk make a flying pitch angle of 95 ?rad or more.
    Type: Grant
    Filed: January 27, 2002
    Date of Patent: January 10, 2006
    Assignee: Fujitsu Limtied
    Inventors: Toru Yokohata, Yoshiharu Kasamatsu, Satoru Momose, Takayuki Yamamoto
  • Publication number: 20050264937
    Abstract: A head slider to which little amount of contaminants is adhered, that can form a uniform and flat head lubricant layer surface and that has excellent ultra-low floating properties, as well as a magnetic recording device equipped with the head slider are provided. The head slider is equipped with a head slider lubricant layer having an average film thickness of not more than 2.5 nm, and composed of a water-repellent resin, the lubricant layer being formed on the head slider surface and head slider protection layer surface facing the magnetic recording medium, and the surface tension of the head slider lubricant layer determined by the Fowkes equation is not more than those of the head slider surface and head slider protection layer surface.
    Type: Application
    Filed: February 8, 2005
    Publication date: December 1, 2005
    Applicant: FUJITSU LIMITED
    Inventors: Hiroshi Chiba, Keiji Watanabe, Yoshiharu Kasamatsu, Takayuki Musashi, Yukiko Oshikubo, Eishin Yamakawa, Takeshi Toukairin, Jun Watanabe, Norikazu Nakamura
  • Publication number: 20050233175
    Abstract: A first protection layer is overlaid on the surface of a recording layer in a recording medium. A second protection layer is overlaid on the surface of the recording layer at a position adjacent the first protection layer. The second protection layer has a composition different from that of the first protection layer. The first and second protection layers have different compositions, so that the overall protection layer is allowed to have an unequal property. The second protection layer may have a hardness higher than that of the first protection layer. A higher hardness of the second protection layer serves to avoid damages on the surface of the recording medium rather than the first protection layer. The recording medium can reliably be protected from collision or contact of an object.
    Type: Application
    Filed: August 17, 2004
    Publication date: October 20, 2005
    Applicant: FUJITSU LIMITED
    Inventors: Takayuki Musashi, Yoshiharu Kasamatsu
  • Publication number: 20050201012
    Abstract: A magnetic head slider comprises a slider body comprising a base portion made of an altic material and an element-forming portion, made of alumina, having formed thereon magnetic conversion elements. Slider-flying rails protruding beyond the surface of the slider body are provided. A first protection film is formed on the surface of the slider body to cover a boundary between the element-forming portion and the base portion to thereby prevent a lubricant of a magnetic disk from depositing on the boundary between the base portion and the element-forming portion. Second protection films are formed on the surfaces of the slider-flying rails to protect the magnetic conversion elements from being corroded and damaged. Further, when pneumatic bearings are provided on the slider-flying rails, third protection films are formed on the surfaces of the pneumatic bearings.
    Type: Application
    Filed: May 12, 2005
    Publication date: September 15, 2005
    Applicant: FUJITSU LIMITED
    Inventors: Yoshiharu Kasamatsu, Susumu Yoshida, Takayuki Musashi
  • Publication number: 20050157426
    Abstract: A medium-opposed surface of a slider body is opposed to a recording medium. A rail is defined on the medium-opposed surface. A groove is defined on the medium-opposed surface between the trailing end of the rail and the trailing end of the medium-opposed surface. A lubricating agent is forced to flow into the groove based on the meniscus effect. Airflow acting on the medium-opposed surface serves to lead the lubricating agent along the groove to the edge of the medium-opposed surface. The lubricating agent is then blown over from the end of the groove at the edge of the medium-opposed surface. The lubricating agent is in this manner prevented from staying between the trailing end of the rail and the trailing end of the medium-opposed surface. The head slider is thus allowed to keep flying in a stable flying attitude.
    Type: Application
    Filed: March 10, 2005
    Publication date: July 21, 2005
    Inventors: Takayuki Musashi, Yoshiharu Kasamatsu
  • Patent number: 6903901
    Abstract: A protector protuberance is formed on a head slider incorporated in a recording medium drive such as a hard disk drive. The protector protuberance is allowed to collide against a contamination on a recording medium in front of a head element mounted on the head slider. The head element can be protected from collision against the contamination behind the protector protuberance. The protector protuberance is located as close to the head element as possible. Even with a smaller protector protuberance, the front and rear support protrusions contact the recording medium so as to hold the slider body above the surface of the recording medium. An increase can be prevented in the adsorption acting between the slider body and a lubricant agent spreading over the surface of the recording medium. A smaller protector protuberance enables the head element to approach the recording medium as close as possible upon read/write operations.
    Type: Grant
    Filed: March 22, 2002
    Date of Patent: June 7, 2005
    Assignee: Fujitsu Limited
    Inventors: Yoshiharu Kasamatsu, Hiroyuki Hyodo, Susumu Yoshida, Toru Yokohata, Masaki Kameyama, Kenrou Yamamoto, Masaharu Sugimoto