Patents by Inventor Junichi Akiyama

Junichi Akiyama 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: 20050139214
    Abstract: An oxygen concentrating apparatus including an output variable type compressor. Oxygen-concentrated gas may be supplied either continuously or synchronized with inhalation or timing of inhalations. In one aspect, when synchronous operation is selected, the compressor is operated at a lower output in comparison with continuous supply operation. In a second aspect, when synchronous operation is selected, the supply quantity of oxygen-concentration gas is set to zero during the exhalation period.
    Type: Application
    Filed: October 27, 2004
    Publication date: June 30, 2005
    Inventors: Hideaki Yagi, Junichi Akiyama
  • Patent number: 6894857
    Abstract: A method of designing a thermally-assisted magnetic recording apparatus having a magnetic recording medium, a heater and a magnetic head includes, determining a stable retention time tst for recorded magnetization and a thermal-fluctuation stability coefficient ?st calculated from ?(T)=KuV/kBT, where Ku is a magnetic anisotropy energy density, V is an activation volume, and kB is Boltzmann's constant, obtaining an equivalent degradation time tEQ calculated from tEQ=?(?tEQ), that sums values of ?tEQ within a period of time ?t for a time span during which the medium is substantially degraded, where ?tEQ=exp(ln(?t)????st) and ? is a thermal-fluctuation stability coefficient for a medium temperature T in ?t, and determining specifications of the medium, the heater and the magnetic head in a manner to meet the relationship of tEQ<tst.
    Type: Grant
    Filed: September 17, 2001
    Date of Patent: May 17, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akira Kikitsu, Junichi Akiyama
  • Patent number: 6881495
    Abstract: A magnetic recording medium capable of alleviating thermal fluctuation and improving the recording density includes a functional layer (12) containing a magnetic material, and a recording layer (11) overlying the functional layer and containing a magnetic material. The recording layer contains a plurality of magnetic grains (51) and a nonmagnetic material (52) existing among the magnetic grains, and the functional layer and the recording layer exert exchange coupling interaction in a direction making a substantially orthogonal relation with each other at the room temperature.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: April 19, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akira Kikitsu, Tadashi Kai, Junichi Akiyama
  • Publication number: 20050041335
    Abstract: A magnetic recording medium capable of alleviating thermal fluctuation and improving the recording density includes a functional layer (12) containing a magnetic material, and a recording layer (11) overlying the functional layer and containing a magnetic material. The recording layer contains a plurality of magnetic grains (51) and a nonmagnetic material (52) existing among the magnetic grains, and the functional layer and the recording layer exert exchange coupling interaction in a direction making a substantially orthogonal relation with each other at the room temperature.
    Type: Application
    Filed: September 22, 2004
    Publication date: February 24, 2005
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Akira Kikitsu, Tadashi Kai, Junichi Akiyama
  • Publication number: 20050036225
    Abstract: A magnetic recording-reproducing apparatus has a magnetic recording medium having a nonmagnetic substrate, and a functional layer and a recording layer formed on the nonmagnetic substrate, the recording layer exhibiting a magnetic anisotropy energy density KuRL, the functional layer developing ferromagnetism upon irradiation with light so as to exhibit a magnetic anisotropy energy density KuFL lower than the magnetic anisotropy energy density KuRL and the functional layer serving to lower the magnetic anisotropy energy density of the recording layer through exchange coupling interaction with the recording layer when the functional layer is irradiated with light, a light source which irradiates the functional layer with light, and a magnetic head having a writing head writing signal magnetization by applying a magnetic field to the recording layer and a reading head reading the signal magnetization recorded in the recording layer.
    Type: Application
    Filed: September 21, 2004
    Publication date: February 17, 2005
    Inventors: Tadashi Kai, Akira Kikitsu, Toshihiko Nagase, Tomoyuki Maeda, Junichi Akiyama
  • Publication number: 20050018547
    Abstract: A pair of members opposed to each other via a gap are commonly used as an evanescent light probe and a writing magnetic head. When the spacing and width of the gap are smaller than the wavelength ? of injected light, highly intensive evanescent light is generated from the gap position of the opposite surface. Magnetic writing is carried out by applying a recording magnetic field from the pair of members to a medium heated by the evanescent light.
    Type: Application
    Filed: August 18, 2004
    Publication date: January 27, 2005
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Junichi Akiyama, Akira Kikitsu, Tadashi Kai, Toshihiko Nagase, Tomoyuki Maeda
  • Patent number: 6837244
    Abstract: A small oxygen enriching apparatus which can supply oxygen-enriched gas at high flow rate without imparting unnatural sensation to a user, as well as a controller and recording medium therefore. In step 100, a judgment is made as to whether a flow rate set by use of a flow-rate setting unit 47 is equal to or less than a continuous base flow rate (2 liters/min). When the set flow rate is a low flow rate of not greater than 2 liters/min, breath-synchronized operation is not performed (continuous supply is to be performed), and therefore, in step 110, oxygen-enriched gas is supplied continuously at the set flow rate. When the set flow rate is a high flow rate of greater than 2 liters/min, breath-synchronized operation is to be performed (supply during the inhalation period only of each breathing cycle), and therefore, in step 120, oxygen-enriched gas is continuously supplied at the continuous base flow rate.
    Type: Grant
    Filed: September 21, 2001
    Date of Patent: January 4, 2005
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Hideaki Yagi, Takahito Kojima, Junichi Akiyama
  • Patent number: 6830824
    Abstract: A magnetic recording medium has a substrate, a base layer formed on the substrate and including a magnetic material, a switching layer formed on the base layer and including a nonmagnetic material, and a recording layer formed on the switching layer and having a structure comprising magnetic particles and a nonmagnetic wall buried between the magnetic particles. The medium meets the condition of TcB>Tsw, where TcB is a Curie temperature of the base layer, and Tsw is a temperature at which the recording layer and the base layer begin to exert exchange coupling interaction.
    Type: Grant
    Filed: June 12, 2001
    Date of Patent: December 14, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akira Kikitsu, Junichi Akiyama, Katsutaro Ichihara, Tadashi Kai, Toshihiko Nagase, Tomoyuki Maeda
  • Publication number: 20040184361
    Abstract: Electrons are directed from an electron emitter towards a magnetic recording medium to heat a recording portion of the magnetic recording medium and magnetic information is written by a magnetic recording head to the temperature-elevated recording portion. Otherwise, a magnetic head having a magnetic pole is used and the magnetic pole serves as an electron emitter as well. Alternatively, a space between the electron emitter and recording medium is made shorter smaller the mean free path of electrons in the atmosphere to considerably improve the recording density.
    Type: Application
    Filed: March 5, 2004
    Publication date: September 23, 2004
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Katsutaro Ichihara, Junichi Akiyama, Akira Kikitsu, Tsutomu Tanaka, Kuniyoshi Tanaka
  • Patent number: 6795380
    Abstract: A pair of members opposed to each other via a gap are commonly used as an evanescent light probe and a writing magnetic head. When the spacing and width of the gap are smaller than the wavelength &lgr; of injected light, highly intensive evanescent light is generated from the gap position of the opposite surface. Magnetic writing is carried out by applying a recording magnetic field from the pair of members to a medium heated by the evanescent light.
    Type: Grant
    Filed: March 29, 2002
    Date of Patent: September 21, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Junichi Akiyama, Akira Kikitsu, Tadashi Kai, Toshihiko Nagase, Tomoyuki Maeda
  • Patent number: 6777078
    Abstract: A magnetic recording medium has a substrate, an underlayer formed on the substrate, a magnetic layer formed on the underlayer and including crystal grains having an L10 structure mainly including Fe and Pt, mainly including Fe and Pd, or mainly including Co and Pt, and the crystal grains further including 0.1 to 50 atomic percent of at least one additive element dissolved therein.
    Type: Grant
    Filed: January 18, 2002
    Date of Patent: August 17, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoyuki Maeda, Akira Kikitsu, Toshihiko Nagase, Junichi Akiyama
  • Patent number: 6741524
    Abstract: Electrons are directed from an electron emitter towards a magnetic recording medium to heat a recording portion of the magnetic recording medium and magnetic information is written by a magnetic recording head to the temperature-elevated recording portion. Otherwise, a magnetic head having a magnetic pole is used and the magnetic pole serves as an electron emitter as well. Alternatively, a space between the electron emitter and recording medium is made shorter smaller the mean free path of electrons in the atmosphere to considerably improve the recording density.
    Type: Grant
    Filed: December 28, 2000
    Date of Patent: May 25, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsutaro Ichihara, Junichi Akiyama, Akira Kikitsu, Tsutomu Tanaka, Kuniyoshi Tanaka
  • Publication number: 20040053078
    Abstract: This invention uses a perpendicular magnetic recording medium in which first and second magnetic recording layers are coupled by antimagnetic exchange coupling, or a longitudinal magnetic recording medium in which three or more predetermined interlayers are formed between first and second magnetic recording layers, and these layers are coupled by antimagnetic exchange coupling.
    Type: Application
    Filed: June 27, 2003
    Publication date: March 18, 2004
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Akira Kikitsu, Junichi Akiyama, Tadashi Kai, Toshihiko Nagase, Tomoyuki Maeda, Hisanori Aikawa, Soichi Oikawa, Yoichiro Tanaka
  • Publication number: 20040051994
    Abstract: A magnetic recording medium has a substrate, and a servo signal recording magnetic layer whose magnetization is oriented in a direction perpendicular to a surface thereof, a non-magnetic layer and a data recording magnetic layer, which are stacked on the substrate in the order mentioned. The servo signal recording magnetic layer has a coercivity higher than that of the data recording magnetic layer. The servo signal recording magnetic layer has servo tracks formed with a track pitch Tps, the servo tracks adjacent to each other in a track width direction being magnetized to opposite directions perpendicular to the film surface.
    Type: Application
    Filed: March 26, 2003
    Publication date: March 18, 2004
    Inventors: Junichi Akiyama, Akira Kikitsu, Tadashi Kai, Toshihiko Nagase, Tomoyuki Maeda, Hisanori Aikawa
  • Publication number: 20030214742
    Abstract: A magnetic recording apparatus comprises a magnetic field impression unit, a current supplying unit and a controlling unit t. The magnetic field impression unit impresses a magnetic field to a magnetic recording medium. The current supplying unit supplies a current to the magnetic recording medium. The controlling unit makes the current supplying unit supply the current to the magnetic recording medium while making the magnetic field impression unit impress the magnetic field to at least a unit of a magnetic recording unit of the magnetic recording medium. Thus, a information is recorded magnetically by making a direction of a magnetization of the magnetic recording unit of the magnetic recording medium in a predetermined direction.
    Type: Application
    Filed: March 28, 2003
    Publication date: November 20, 2003
    Inventors: Tadashi Kai, Masayuki Takagishi, Masashi Sahashi, Junichi Akiyama, Hitoshi Iwasaki, Akira Kikitsu
  • Patent number: 6636460
    Abstract: In a thermally-assisted magnetic recorder configured to heat a medium with a heat source like a light beam and thereby decrease the coercive force of a recording portion so as to magnetically record information on the recording portion decreased in coercive force by applying a recording magnetic field from a recording magnetic pole thereto, relative timing between heating of the medium and magnetic recording is optimized by locating a reversing point of magnetization, in which the coercive force of the recording portion equals the intensity of the recording magnetic field, in the leading side of the trailing edge of the recording magnetic pole.
    Type: Grant
    Filed: December 28, 2000
    Date of Patent: October 21, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Junichi Akiyama, Katsutaro Ichihara, Akira Kikitsu
  • Publication number: 20030053238
    Abstract: A magnetic recording-reproducing apparatus has a magnetic recording medium having a nonmagnetic substrate, and a functional layer and a recording layer formed on the nonmagnetic substrate, the recording layer exhibiting a magnetic anisotropy energy density KuRL, the functional layer developing ferromagnetism upon irradiation with light so as to exhibit a magnetic anisotropy energy density KuFL lower than the magnetic anisotropy energy density KuRL and the functional layer serving to lower the magnetic anisotropy energy density of the recording layer through exchange coupling interaction with the recording layer when the functional layer is irradiated with light, a light source which irradiates the functional layer with light, and a magnetic head having a writing head writing signal magnetization by applying a magnetic field to the recording layer and a reading head reading the signal magnetization recorded in the recording layer.
    Type: Application
    Filed: September 9, 2002
    Publication date: March 20, 2003
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tadashi Kai, Akira Kikitsu, Toshihiko Nagase, Tomoyuki Maeda, Junichi Akiyama
  • Publication number: 20030017364
    Abstract: A magnetic recording medium capable of alleviating thermal fluctuation and improving the recording density includes a functional layer (12) containing a magnetic material, and a recording layer (11) overlying the functional layer and containing a magnetic material. The recording layer contains a plurality of magnetic grains (51) and a nonmagnetic material (52) existing among the magnetic grains, and the functional layer and the recording layer exert exchange coupling interaction in a direction making a substantially orthogonal relation with each other at the room temperature.
    Type: Application
    Filed: June 28, 2002
    Publication date: January 23, 2003
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Akira Kikitsu, Tadashi Kai, Junichi Akiyama
  • Patent number: 6483673
    Abstract: A GMR element part is formed of a laminated structure which comprises at least one pair of ferromagnetic layers and a nonmagnetic intermediate layer interposed between the pair of ferromagnetic layers. Signal magnetic field detecting ferromagnetic layers will be optionally disposed one each outside the pair of ferromagnetic layers. The GMR element part consists of a laminated structure which is provided with one pair of GMR ferromagnetic layers opposed to each other across a nonmagnetic intermediate layer or a laminated structure which is provided with one pair of GMR ferromagnetic layer opposed to each other across a nonmagnetic intermediate layer and at least one low-permeability ferromagnetic layer disposed there between through the medium of a nonmagnetic intermediate layer.
    Type: Grant
    Filed: May 28, 1998
    Date of Patent: November 19, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hitoshi Iwasaki, Yuichi Ohsawa, Reiko Kondoh, Yuzo Kamiguchi, Susumu Hashimoto, Tomomi Funayama, Hiromi Fuke, Junichi Akiyama, Kazuhiro Saito
  • Publication number: 20020167870
    Abstract: A pair of members opposed to each other via a gap are commonly used as an evanescent light probe and a writing magnetic head. When the spacing and width of the gap are smaller than the wavelength &lgr; of injected light, highly intensive evanescent light is generated from the gap position of the opposite surface. Magnetic writing is carried out by applying a recording magnetic field from the pair of members to a medium heated by the evanescent light.
    Type: Application
    Filed: March 29, 2002
    Publication date: November 14, 2002
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Junichi Akiyama, Akira Kikitsu, Tadashi Kai, Toshihiko Nagase, Tomoyuki Maeda