Patents by Inventor Naoto Igarashi

Naoto Igarashi 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: 20090197782
    Abstract: A soft magnetic material includes a plurality of composite magnetic particles including a metal magnetic particle and an insulating film surrounding a surface of the metal magnetic particle. The insulating film also contains a phosphate. The soft magnetic material further includes an aromatic polyetherketone resin and a metallic soap and/or an inorganic lubricant having a hexagonal crystal structure. The metallic soap and the inorganic lubricant are particles with an average particle size of not more than 2.0 ?m.
    Type: Application
    Filed: May 15, 2007
    Publication date: August 6, 2009
    Applicants: SUMITOMO ELECTRIC INDUSTRIES, LTD., DENSO CORPORATION, SUMITOMO ELECTRIC SINTERED ALLOY, LTD.
    Inventors: Naoto Igarashi, Takao Nishioka, Yoshiyuki Shimada, Tsuyoshi Akao
  • Publication number: 20090047519
    Abstract: The soft magnetic material includes a plurality of composite magnetic particles having a metal magnetic particle and an insulating film surrounding the surface of the metal magnetic particle. The metal magnetic particle contains iron as the main component. The insulating film contains aluminum, silicon, phosphorus, and oxygen. The insulating film satisfies the relationship 0.4?MAl/(MAl+MSi)?0.9 and the relationship of 0.25?(MAl+MSi)/MP?1.0 in the case that molar amount of aluminum contained in the insulating film is represented by MAl, the sum of the molar amount of aluminum contained in the insulating film and the molar amount of silicon contained in the insulating film is represented by (MAl+MSi), and the molar amount of phosphorus contained in the insulating film is represented by MP.
    Type: Application
    Filed: November 22, 2006
    Publication date: February 19, 2009
    Applicants: SUMITOMO ELECTRIC INDUSTRIES, LTD., TODA KOGYO CORP.
    Inventors: Toru Maeda, Naoto Igarashi, Haruhisa Toyoda, Seiji Ishitani, Hiroko Morii, Kazuyuki Hayashi
  • Publication number: 20080248245
    Abstract: A soft magnetic material includes a plurality of composite magnetic particles. Each of the plurality of composite magnetic particles has a metal magnetic particle including iron, a lower film surrounding the surface of the metal magnetic particle and including a nonferrous metal, and an insulating upper film surrounding the surface of the lower film and including an inorganic compound. The inorganic compound contains at least one element of oxygen and carbon. The nonferrous metal has an affinity with at least one of oxygen and carbon that is larger than such affinity of iron. The nonferrous metal has a diffusion coefficient with respect to at least one of oxygen and carbon that is smaller than such diffusion coefficient of iron. Thus, a soft magnetic material that provides desirable magnetic properties, a method of manufacturing a soft magnetic material, a dust core, and a method of manufacturing a dust core are provided.
    Type: Application
    Filed: July 20, 2006
    Publication date: October 9, 2008
    Inventors: Toru Maeda, Haruhisa Toyoda, Naoto Igarashi, Kazuhiro Hirose, Seiji Ishitani, Hiroko Morii, Kazuyuki Hayashi
  • Publication number: 20080231409
    Abstract: The object of the present invention is to provide a powder core and method for making the same that is equipped with insulative coating having superior heat resistance, with the coating making it possible to adequately restrict the flow of eddy currents between particles. The powder core is equipped with a plurality of compound magnetic particles bonded to each other. Each of said plurality of composite magnetic particles includes: a metal magnetic particle 10; an insulative lower layer coating 20 surrounding a surface 10a of said metal magnetic particle 10; an upper layer coating 30 surrounding said lower layer coating 20 and containing silicon; and dispersed particles 50 containing a metal oxide compound and disposed in said lower layer coating 20 and/or said upper layer coating 30. A mean particle diameter R of the dispersed particles 50 meets the condition 10 nm<R?2 T, where the average thickness of the coating combining the lower layer coating 20 and the upper layer coating 30 is T.
    Type: Application
    Filed: January 28, 2005
    Publication date: September 25, 2008
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Hirokazu Kugai, Naoto Igarashi, Toru Maeda, Kazuhiro Hirose, Haruhisa Toyoda, Koji Mimura, Takao Nishioka
  • Publication number: 20080061264
    Abstract: A soft magnetic material has a plurality of composite magnetic particles. Each of the plurality of composite magnetic particles has a metal magnetic particle and an insulating coating covering the metal magnetic particle. Each of the plurality of composite magnetic particles has a ratio of a maximum diameter to an equivalent circle diameter greater than 1.0 and at most 1.3, and a specific surface area of at least 0.10 m2/g.
    Type: Application
    Filed: March 9, 2006
    Publication date: March 13, 2008
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Toru Maeda, Naoto Igarashi, Haruhisa Toyoda
  • Publication number: 20080041496
    Abstract: A method of producing a soft magnetic material includes the steps of preparing soft magnetic powder containing a plurality of soft magnetic particles etching the soft magnetic powder to remove surfaces of the soft magnetic particles and, after the etching step, heat-treating the soft magnetic powder in a finely divided state at a temperature of not less than 400° C. and not more than 900° C. By this method configured as above, desired magnetic characteristics can be obtained.
    Type: Application
    Filed: March 29, 2005
    Publication date: February 21, 2008
    Inventors: Toru Maeda, Naoto Igarashi, Kazuhiro Hirose, Haruhisa Toyoda
  • Publication number: 20070241622
    Abstract: A power magnetic core has a start section and a termination section. In the powder magnetic core, lines of magnetic force are formed from the start section to the termination section. The powder magnetic core comprises a first portion disposed on the shortest magnetic path of the lines of magnetic force that connects the start section and the termination section and having a permeability ?a and a second portion disposed apart from the shortest magnetic path of the lines of magnetic force and having a permeability ?b greater than ?a. With this constitution, a desired magnetic characteristic is achieved, and the iron loss is sufficiently reduced.
    Type: Application
    Filed: December 15, 2004
    Publication date: October 18, 2007
    Inventors: Haruhisa Toyoda, Naoto Igarashi, Hitoshi Oyama, Yasuhiro Endo, Ryoji Mizutani
  • Publication number: 20070235109
    Abstract: A soft magnetic material is a soft magnetic material including a composite magnetic particle (30) having a metal magnetic particle (10) mainly composed of Fe and an insulating coating (20) covering metal magnetic particle (10), and insulating coating (20) contains an iron phosphate compound and an aluminum phosphate compound. The atomic ratio of Fe contained in a contact surface of insulating coating (20) in contact with metal magnetic particle (10) is larger than the atomic ratio of Fe contained in the surface of insulating coating (20). The atomic ratio of Al contained in the contact surface of insulating coating (20) in contact with metal magnetic particle (10) is smaller than the atomic ratio of Al contained in the surface of insulating coating (20). Thus, iron loss can be reduced.
    Type: Application
    Filed: September 29, 2005
    Publication date: October 11, 2007
    Inventors: Toru Maeda, Naoto Igarashi, Haruhisa Toyoda, Hirokazu Kugai, Kazuyuki Hayashi, Hiroko Morii, Seiji Ishitani
  • Publication number: 20070194267
    Abstract: A soft magnetic material includes: a plurality of composite magnetic particles formed from a metal magnetic particle and an insulative coating surrounding a surface of the metal magnetic particle and containing metallic salt phosphate and/or oxide; and a lubricant formed as fine particles added at a proportion of at least 0.001 percent by mass and no more than 0.1 percent by mass relative to the plurality of composite magnetic particles. With this structure, superior lubrication is provided during compacting and desired magnetic characteristics can be obtained after compacting.
    Type: Application
    Filed: March 29, 2005
    Publication date: August 23, 2007
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Kazuhiro Hirose, Haruhisa Toyoda, Takao Nishioka, Naoto Igarashi, Toru Maeda, Yoshiyuki Shimada
  • Publication number: 20070169851
    Abstract: An object of the present invention is to provide a soft magnetic material exhibiting excellent magnetic characteristics regardless of the frequency to be applied and a dust core produced from the soft magnetic material. The means for solving the invention is a soft magnetic material that comprises metal magnetic particles 10 containing iron and oxygen. The ratio of oxygen contained in metal magnetic particles 10 is more than 0 and less than 0.05% by mass. A dust core produced using such a soft magnetic material has a coercive force of 2.0×102 A/m or less.
    Type: Application
    Filed: January 26, 2005
    Publication date: July 26, 2007
    Inventors: Hirokazu Kugai, Naoto Igarashi, Toru Maeda, Kazuhiro Hirose, Haruhisa Toyoda, Koji Mimura, Takao Nishioka
  • Publication number: 20070102066
    Abstract: A method for making soft magnetic material includes: a first heat treatment step applying a temperature of at least 400 deg C. and less than 900 deg C. to metal magnetic particles (10); a step for forming a plurality of compound magnetic particles (30) in which said metal magnetic particles (10) are surrounded by insulation film (20); and a step for forming a shaped body by compacting a plurality of compound magnetic particles (30). This provides a method for making soft magnetic material that provides desired magnetic properties.
    Type: Application
    Filed: October 1, 2004
    Publication date: May 10, 2007
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Haruhisa Toyoda, Hirokazu Kugai, Kazuhiro Hirose, Naoto Igarashi, Takao Nishioka
  • Publication number: 20060216507
    Abstract: The present invention provides a soft magnetic material and a powder magnetic core having desired magnetic characteristics. A soft magnetic material contains a metal magnetic powder 10. The metal magnetic powder 10 is formed from crystals 1 with an average size, as determined from X-ray diffraction, of at least 30 nm. It would be preferable, in the metal magnetic particles 10, for crystal grains 2 to have an average size of at least 10 microns.
    Type: Application
    Filed: October 7, 2004
    Publication date: September 28, 2006
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Haruhisa Toyoda, Hirokazu Kugai, Kazuhiro Hirose, Naoto Igarashi, Takao Nishioka
  • Publication number: 20060159960
    Abstract: A soft magnetic material includes a plurality of composite magnetic particles. Each of the plurality of composite magnetic particles has: a metal magnetic particle including iron; a lower film surrounding the surface of the metal magnetic particle and including a nonferrous metal; and an insulating upper film surrounding the surface of the lower film and including at least one of oxygen and carbon. The nonferrous metal has an affinity with the at least one of oxygen and carbon included in the upper film that is larger than such affinity of iron; or the nonferrous metal has a diffusion coefficient with respect to the at least one of oxygen and carbon included in the upper film that is smaller than such diffusion coefficient of iron. This configuration provides desirable magnetic properties.
    Type: Application
    Filed: February 22, 2005
    Publication date: July 20, 2006
    Inventors: Toru Maeda, Naoto Igarashi, Haruhisa Toyoda, Kazuhiro Hirose
  • Publication number: 20050257854
    Abstract: The object of the present invention is to provide a method for manufacturing a soft magnetic material, a soft magnetic material, a method for manufacturing a P/M soft magnetic material, and a P/M soft magnetic material which achieve the desired magnetic properties. In the method for manufacturing the soft magnetic material of the present invention, there is a first heat treatment step (step S3) in which a metal magnetic particle 10, which has iron as its main component, is heat treated to a temperature of 900 degrees C. or greater and less than the melting point of metal magnetic particle 10. After the first heat treatment step (step S3), there is a step for forming a plurality of composite magnetic particles 30 which are metal magnetic particles 10 surrounded by an insulation covering 20 (step S6).
    Type: Application
    Filed: May 11, 2005
    Publication date: November 24, 2005
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Toru Maeda, Naoto Igarashi, Haruhisa Toyoda, Koji Mimura
  • Publication number: 20050016633
    Abstract: The method of manufacturing soft magnetic articles comprises a step of preparing a melt solution containing soft magnetic materials and a step of forming soft magnetic particles from the melt solution in a magnetic field by an atomization rapid solidification method.
    Type: Application
    Filed: July 20, 2004
    Publication date: January 27, 2005
    Inventors: Hirokazu Kugai, Haruhisa Toyoda, Naoto Igarashi, Kazuhiro Hirose, Takao Nishioka, Akihiko Ikegaya, Ryosuke Hata, Hitoshi Oyama, Kenichi Sato, Kazuhiko Hayashi, Masayuki Hirose, koji Muranaka