Patents by Inventor Tsuyoshi Akao

Tsuyoshi Akao 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: 8241518
    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: Grant
    Filed: May 15, 2007
    Date of Patent: August 14, 2012
    Assignees: Sumitomo Electric Industries, Ltd., Denso Corporation, Sumitomo Electric Sintered Alloy, Ltd.
    Inventors: Naoto Igarashi, Takao Nishioka, Yoshiyuki Shimada, Tsuyoshi Akao
  • Patent number: 8062583
    Abstract: A method for producing a soft magnetic powdered core includes preparing a mixture of a soft magnetic powder and a resin powder, compacting the mixture into a predetermined shape so as to obtain a compact, and heating the compact. The resin powder has a median size of not more than 30 ?m, a maximum particle size of not more than 100 ?m, and a specific surface area of not less than 1.0 m2/cm3, and the additive amount thereof is 0.005 to 2 vol %.
    Type: Grant
    Filed: March 17, 2008
    Date of Patent: November 22, 2011
    Assignees: Hitachi Powdered Metals Co., Ltd., Denso Corporation
    Inventors: Chio Ishihara, Kazuo Asaka, Kohei Muramatsu, Tsuyoshi Akao, Hirotake Hamamatsu
  • Patent number: 8029626
    Abstract: A method for producing a soft magnetic powdered core comprises a mixing step for forming a raw powder by adding a thermoplastic resin powder to a soft magnetic powder and mixing them, a compacting step for forming a compact by compacting the raw powder into a predetermined shape, a melting and setting step for the resin in which the resin of the compact is melted by heating to at least the melting point of the thermoplastic resin and the melted resin is set by cooling to a room temperature, and a crystallizing step for the resin in which the set resin is heated to not less than the exothermic onset temperature and not more than the endothermic onset temperature, which are measured by DSC analysis of the thermoplastic resin, and is cooled to a room temperature.
    Type: Grant
    Filed: March 17, 2008
    Date of Patent: October 4, 2011
    Assignees: Hitachi Powered Metals Co., Ltd., Denso Corporation
    Inventors: Chio Ishihara, Kazuo Asaka, Kohei Muramatsu, Tsuyoshi Akao, Hirotake Hamamatsu
  • 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
  • Patent number: 7541906
    Abstract: A sintered plunger is used for electromagnetic actuators. The sintered member includes: an outer member composed of a soft magnetic material and having an inner hole formed therein, and a shaft having an end portion which is fitted into the outer member. The shaft is composed of a ferromagnetic steel, the outer member peripheral is composed of a sintered member, and the shaft and the outer member are integrally bonded by sintering. As a result, the overall sintered plunger can have good magnetic properties, a good magnetic attraction, a good wear resistance, and a good fatigue strength. Electromagnetic actuators having high responsiveness required in recent years can be produced.
    Type: Grant
    Filed: September 15, 2004
    Date of Patent: June 2, 2009
    Assignees: Hitachi Powdered Metals Co., Ltd., Denso Corporation
    Inventors: Kazuo Asaka, Tsuyoshi Akao, Aya Hamano
  • Publication number: 20080232995
    Abstract: A method for producing a soft magnetic powdered core includes preparing a mixture of a soft magnetic powder and a resin powder, compacting the mixture into a predetermined shape so as to obtain a compact, and heating the compact. The resin powder has a median size of not more than 30 ?m, a maximum particle size of not more than 100 ?m, and a specific surface area of not less than 1.0 m2/cm3, and the additive amount thereof is 0.005 to 2 vol %.
    Type: Application
    Filed: March 17, 2008
    Publication date: September 25, 2008
    Applicants: HITACHI POWDERED METALS CO., LTD., DENSO CORPORATION
    Inventors: Chio Ishihara, Kazuo Asaka, Kohei Muramatsu, Tsuyoshi Akao, Hirotake Hamamatsu
  • Publication number: 20080230737
    Abstract: A method for producing a soft magnetic powdered core comprises a mixing step for forming a raw powder by adding a thermoplastic resin powder to a soft magnetic powder and mixing them, a compacting step for forming a compact by compacting the raw powder into a predetermined shape, a melting and setting step for the resin in which the resin of the compact is melted by heating to at least the melting point of the thermoplastic resin and the melted resin is set by cooling to a room temperature, and a crystallizing step for the resin in which the set resin is heated to not less than the exothermic onset temperature and not more than the endothermic onset temperature, which are measured by DSC analysis of the thermoplastic resin, and is cooled to a room temperature.
    Type: Application
    Filed: March 17, 2008
    Publication date: September 25, 2008
    Applicants: HITACHI POWERED METALS CO., LTD., DENSO CORPORATION
    Inventors: Chio Ishihara, Kazuo Asaka, Kohei Muramatsu, Tsuyoshi Akao, Hirotake Hamamatsu
  • Patent number: 7273527
    Abstract: The present invention provides a production method for a powdered core, including steps of preparing a mixture including a soft magnetic powder and a resin powder to obtain a mixture, compacting the mixture into a predetermined shape to obtain a green compact and heating the green compact, and wherein the resin powder has a median size of not more than 50 ?m, and the resin powder amount is 0.01 to 5 vol %. The method reduces production cost, and decreases eddy-current loss We and hysteresis loss Wh, whereby a powdered core in which a durability is improved and the technical advantages are expanded can be provided.
    Type: Grant
    Filed: November 2, 2006
    Date of Patent: September 25, 2007
    Assignees: Hitachi Powdered Metals Co., Ltd., Denso Corporation
    Inventors: Chio Ishihara, Kazuo Asaka, Kei Ishii, Tamio Takada, Tsuyoshi Akao, Isao Makino
  • Patent number: 7211158
    Abstract: The present invention provides a production method for a powdered core, including steps of preparing a mixture including a soft magnetic powder and a resin powder to obtain a mixture, compacting the mixture into a predetermined shape to obtain a green compact and heating the green compact, and wherein the resin powder has a median size of not more than 50 ?m, and the resin powder amount is 0.01 to 5 vol %. The method reduces production cost, and decreases eddy-current loss We and hysteresis loss Wh, whereby a powdered core in which a durability is improved and the technical advantages are expanded can be provided.
    Type: Grant
    Filed: September 30, 2003
    Date of Patent: May 1, 2007
    Assignees: Hitachi Powdered Metals Co., Ltd., Denso Corporation
    Inventors: Chio Ishihara, Kazuo Asaka, Kei Ishii, Tamio Takada, Tsuyoshi Akao, Isao Makino
  • Publication number: 20070085644
    Abstract: A sintered plunger is used for electromagnetic actuators. The sintered member includes: an outer member composed of a soft magnetic material and having an inner hole formed therein, and a shaft having an end portion which is fitted into the outer member. The shaft is composed of a ferromagnetic steel, the outer member peripheral is composed of a sintered member, and the shaft and the outer member are integrally bonded by sintering. As a result, the overall sintered plunger can have good magnetic properties, a good magnetic attraction, a good wear resistance, and a good fatigue strength. Electromagnetic actuators having high responsiveness required in recent years can be produced.
    Type: Application
    Filed: September 15, 2004
    Publication date: April 19, 2007
    Applicants: HITACHI POWDERED METALS CO., LTD., DENSO CORPORATION
    Inventors: Kazuo Asaka, Tsuyoshi Akao, Aya Hamano
  • Publication number: 20070051430
    Abstract: The present invention provides a production method for a powdered core, including steps of preparing a mixture including a soft magnetic powder and a resin powder to obtain a mixture, compacting the mixture into a predetermined shape to obtain a green compact and heating the green compact, and wherein the resin powder has a median size of not more than 50 ?m, and the resin powder amount is 0.01 to 5 vol %. The method reduces production cost, and decreases eddy-current loss We and hysteresis loss Wh, whereby a powdered core in which a durability is improved and the technical advantages are expanded can be provided.
    Type: Application
    Filed: November 2, 2006
    Publication date: March 8, 2007
    Applicants: HITACHI POWDERED METALS CO., LTD., DENSO CORPORATION
    Inventors: Chio Ishihara, Kazuo Asaka, Kei Ishii, Tamio Takada, Tsuyoshi Akao, Isao Makino
  • Publication number: 20050242460
    Abstract: The present invention provides a production method for a powdered core, including steps of preparing a mixture including a soft magnetic powder and a resin powder to obtain a mixture, compacting the mixture into a predetermined shape to obtain a green compact and heating the green compact, and wherein the resin powder has a median size of not more than 50 ?m, and the resin powder amount is 0.01 to 5 vol %. The method reduces production cost, and decreases eddy-current loss We and hysteresis loss Wh, whereby a powdered core in which a durability is improved and the technical advantages are expanded can be provided.
    Type: Application
    Filed: September 30, 2003
    Publication date: November 3, 2005
    Applicants: Hitachi Powered Metals Co., Ltd., Denso Corporation
    Inventors: Chio Ishihara, Kazuko Asaka, Kei Ishii, Tamio Takada, Tsuyoshi Akao, Isao Makino