Patents by Inventor Yoshiaki Akachi

Yoshiaki Akachi 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: 7416795
    Abstract: A method for manufacturing magnetic metal powder is provided. In the method, a powdered magnetic metal oxide is supplied to a heat treatment furnace with a carrier gas composed of a reducing gas. The heat treatment furnace is maintained at temperatures above a reducing action starting temperature for the powdered magnetic metal oxide and above a melting point of the magnetic metal in the powder. The powdered magnetic metal oxide is subject to a reducing process, and then magnetic metal particles, the resultant reduced product, is melted to form a melt. The melt is re-crystallized in a succeeding cooling step, to obtain single crystal magnetic metal power in substantially spherical form.
    Type: Grant
    Filed: September 22, 2004
    Date of Patent: August 26, 2008
    Assignee: TDK Corporation
    Inventors: Minoru Takaya, Yoshiaki Akachi, Hisashi Kobuke, Hiroyuki Uematsu
  • Patent number: 7402337
    Abstract: A method for manufacturing spherical ceramic powder is provided. The method includes essentially a spray drying step and a sintering step. In the spray drying step, a spray nozzle is used to spray slurry containing powdered raw material consisting essentially of ceramic ingredients to form liquid droplets, and liquid contents in the liquid droplets are heated and removed to obtain ceramic granular powder. In the sintering step, the ceramic granular powder is sintered to form spherical ceramic powder. The method provides ceramic powder having a mean particle size of about 1-50 ?m and a sphericity of about 0.8 or higher, which is suited for mixing with resin material to form a compound. The ceramic powder has high dispersant and filling properties against the resin material.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: July 22, 2008
    Assignee: TDK Corporation
    Inventors: Minoru Takaya, Yoshiaki Akachi, Tomohiro Sogabe, Hisashi Kobuke
  • Patent number: 7060350
    Abstract: A composite magnetic material including a resin and generally spherical magnetic metal particles of at least one type dispersed in the resin and consisting essentially of single crystal grains, the metal particles having a mean particle size of 0.1 to 10 ?m and each having an insulating coating layer at least partially coated thereon.
    Type: Grant
    Filed: December 28, 2000
    Date of Patent: June 13, 2006
    Assignee: TDK Corporation
    Inventors: Minoru Takaya, Yoshiaki Akachi, Hisashi Kobuke, Toshikazu Endo
  • Patent number: 6872251
    Abstract: A method for manufacturing single crystal ceramic powder is provided. The method includes a powder supply step for supplying powder consisting essentially of ceramic ingredients to a heat treatment area with a carrier gas, a heat treatment step for heating the powder supplied to the heat treatment area at temperatures required for single-crystallization of the powder to form a product, and a cooling step for cooling the product obtained in the heat treatment step to form single crystal ceramic powder. The method provides single crystal ceramic powder consisting of particles with a very small particle size and a sphericity being 0.9 or higher.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: March 29, 2005
    Assignee: TDK Corporation
    Inventors: Minoru Takaya, Yoshiaki Akachi, Hiroyuki Uematsu, Hisashi Kobuke
  • Publication number: 20050056347
    Abstract: A method for manufacturing magnetic metal powder is provided. In the method, a powdered magnetic metal oxide is supplied to a heat treatment furnace with a carrier gas composed of a reducing gas. The heat treatment furnace is maintained at temperatures above a reducing action starting temperature for the powdered magnetic metal oxide and above a melting point of the magnetic metal in the powder. The powdered magnetic metal oxide is subject to a reducing process, and then magnetic metal particles, the resultant reduced product, is melted to form a melt. The melt is re-crystallized in a succeeding cooling step, to obtain single crystal magnetic metal power in substantially spherical form.
    Type: Application
    Filed: September 22, 2004
    Publication date: March 17, 2005
    Inventors: Minoru Takaya, Yoshiaki Akachi, Hisashi Kobuke, Hiroyuki Uematsu
  • Patent number: 6827758
    Abstract: A method for manufacturing magnetic metal powder is provided. In the method, a powdered magnetic metal oxide is supplied to a heat treatment furnace with a carrier gas composed of a reducing gas. The heat treatment furnace is maintained at temperatures above a reducing action starting temperature for the powdered magnetic metal oxide and above a melting point of the magnetic metal in the powder. The powdered magnetic metal oxide is subject to a reducing process, and then magnetic metal particles, the resultant reduced product, is melted to form a melt. The melt is re-crystallized in a succeeding cooling step, to obtain single crystal magnetic metal power in substantially spherical form.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: December 7, 2004
    Assignee: TDK Corporation
    Inventors: Minoru Takaya, Yoshiaki Akachi, Hisashi Kobuke, Hiroyuki Uematsu
  • Patent number: 6793842
    Abstract: A ferrite fine powder having a mean particle size of 0.1 to 30 &mgr;m and made of spherical single-crystal particles. The ferrite fine powder has superior physical properties and excellent magnetic properties desirable for use as a raw material for a dust core of coils, transformers, etc. The powder is prepared by forming a solution or suspension containing a compound or compounds of at least one of the metals forming the ferrite into fine droplets, and thermally decomposing the droplets at elevated temperatures.
    Type: Grant
    Filed: July 6, 2001
    Date of Patent: September 21, 2004
    Assignees: Shoei Chemical Inc., TDK Corporation
    Inventors: Yuji Akimoto, Kazuro Nagashima, Masahiro Ikemoto, Minoru Takaya, Yoshiaki Akachi, Hisashi Kobuke
  • Publication number: 20020197461
    Abstract: A method for manufacturing single crystal ceramic powder is provided. The method includes a powder supply step for supplying powder consisting essentially of ceramic ingredients to a heat treatment area with a carrier gas, a heat treatment step for heating the powder supplied to the heat treatment area at temperatures required for single-crystallization of the powder to form a product, and a cooling step for cooling the product obtained in the heat treatment step to form single crystal ceramic powder. The method provides single crystal ceramic powder consisting of particles with a very small particle size and a sphericity being 0.9 or higher.
    Type: Application
    Filed: May 29, 2002
    Publication date: December 26, 2002
    Inventors: Minoru Takaya, Yoshiaki Akachi, Hiroyuki Uematsu, Hisashi Kobuke
  • Publication number: 20020189401
    Abstract: A method for manufacturing magnetic metal powder is provided. In the method, a powdered magnetic metal oxide is supplied to a heat treatment furnace with a carrier gas composed of a reducing gas. The heat treatment furnace is maintained at temperatures above a reducing action starting temperature for the powdered magnetic metal oxide and above a melting point of the magnetic metal in the powder. The powdered magnetic metal oxide is subject to a reducing process, and then magnetic metal particles, the resultant reduced product, is melted to form a melt. The melt is re-crystallized in a succeeding cooling step, to obtain single crystal magnetic metal power in substantially spherical form.
    Type: Application
    Filed: May 29, 2002
    Publication date: December 19, 2002
    Inventors: Minoru Takaya, Yoshiaki Akachi, Hisashi Kobuke, Hiroyuki Uematsu
  • Publication number: 20020193236
    Abstract: A method for manufacturing spherical ceramic powder is provided. The method includes essentially a spray drying step and a sintering step. In the spray drying step, a spray nozzle is used to spray slurry containing powdered raw material consisting essentially of ceramic ingredients to form liquid droplets, and liquid contents in the liquid droplets are heated and removed to obtain ceramic granular powder. In the sintering step, the ceramic granular powder is sintered to form spherical ceramic powder. The method provides ceramic powder having a mean particle size of about 1-50 &mgr;m and a sphericity of about 0.8 or higher, which is suited for mixing with resin material to form a compound. The ceramic powder has high dispersant and filling properties against the resin material.
    Type: Application
    Filed: May 29, 2002
    Publication date: December 19, 2002
    Inventors: Minoru Takaya, Yoshiaki Akachi, Tomohiro Sogabe, Hisashi Kobuke
  • Publication number: 20020039667
    Abstract: Generally spherical metal particles (1) consisting essentially of single crystal grains, having a mean particle size of 0.1 to 10 &mgr;m are surface coated with an insulating or dielectric layer (2a or 2b) as by a spray pyrolysis process, and the coated metal particles are dispersed in a resin to form a composite magnetic or dielectric material. The composite magnetic material is highly insulating, easy to prepare, free of corrosion and has improved high-frequency characteristics and withstanding voltage. The composite dielectric material has a high dielectric constant even at a reduced content of dielectric. There are also provided a molding material, powder compression molding material, paint, prepreg, and substrate.
    Type: Application
    Filed: December 28, 2000
    Publication date: April 4, 2002
    Applicant: TDK CORPORATION
    Inventors: Minoru Takaya, Yoshiaki Akachi, Hisashi Kobuke, Toshikazu Endo
  • Publication number: 20020017628
    Abstract: A ferrite fine powder having a mean particle size of 0.1 to 30 &mgr;m and consisting of spherical single-crystal particles. The ferrite fine powder has superior physical properties and excellent magnetic properties desirable for the use as a raw material for a dust core of coils, transformers, etc. The powder is prepared by forming a solution or suspension containing a compound or compounds of at least one of the metals composing ferrite into fine droplets, and thermally decomposing the droplets at elevated temperatures.
    Type: Application
    Filed: July 6, 2001
    Publication date: February 14, 2002
    Inventors: Yuji Akimoto, Kazuro Nagashima, Masahiro Tkemoto, Minoru Takaya, Yoshiaki Akachi, Hisashi Kobuke
  • Patent number: 6225876
    Abstract: A feed-through EMI filter includes a hollow outer conductor, an inner conductor passing through the outer conductor, and a composite magnetic material of magnetic metal flakes disposed between the outer conductor and the inner conductor. Both ends of the outer conductor are closed by insulating lids supporting the inner conductor in a feed-through arrangement. The composite magnetic material has a higher complex relative permeability at GHz frequencies than ferrites and produces a large insertion loss.
    Type: Grant
    Filed: March 15, 1999
    Date of Patent: May 1, 2001
    Assignees: Electromagnetic Compatibility Research Laboratories Co., Ltd., TDK Corporation
    Inventors: Tadaharu Akino, Takashi Tanaka, Hisanori Sasaki, Yoshiaki Akachi, Tadashige Konno
  • Patent number: 4939459
    Abstract: A magnetic sensor is provided for use in detecting an external magnetic field, typically geomagnetism. Pulse or alternating current is applied across a wire or strip-shaped electrically conductive, magnetic body in its longitudinal direction to create an internal magnetic field in the magnetic body. A pick-up winding is wound around the magnetic body. The sensor detects an electric signal developed in the winding as a result of interaction of the internal and external magnetic fields.
    Type: Grant
    Filed: December 21, 1988
    Date of Patent: July 3, 1990
    Assignee: TDK Corporation
    Inventors: Yoshiaki Akachi, Mutumi Kinosita
  • Patent number: 4635019
    Abstract: A coil apparatus for the use of a switching power supply circuit has been found. The coil apparatus having two overlapped coil bobbins has an improved winding arrangement. This arrangement is such that one (P.sub.1) of primary windings which are provided for an inner bobbin are divided into two windings (P.sub.11, P.sub.12) which are electrically coupled with each other, and remaining primary windings (P.sub.2) are sandwiched between the two divided windings (P.sub.11, P.sub.12).
    Type: Grant
    Filed: August 14, 1985
    Date of Patent: January 6, 1987
    Assignee: TDK Corporation
    Inventors: Yoshiaki Akachi, Takeo Matsumaru
  • Patent number: 4617543
    Abstract: An improved structure of a coil bobbin for a transformer in a switching power supply circuit. The coil bobbin comprises an outer bobbin (30) having a first hollow cylindrical member (12) having a first flange (13) located around one end thereof, said first flange having a first terminal plate (15) with a plurality of a first terminal pins (16) and a first grooves (26) for accommodating lead wires, the first member (12) having a second flange (31) located around the other end thereof, and an inner bobbin (2) having a second hollow cylindrical member (21) having a third flange (22) located around one end thereof, the third flange having a second terminal plate (23) with a plurality of a second terminal pins (24) and a second grooves (25) for accommodating lead wires. The coil bobbin in assembled by inserting the second hollow member (21) into the first hollow member (12) so that the first and second terminal plates are parallel with each other in the horizontal direction.
    Type: Grant
    Filed: January 24, 1985
    Date of Patent: October 14, 1986
    Assignee: TDK Corporation
    Inventors: Yoshiaki Akachi, Yasuo Kyoso, Takeo Matsumaru