Patents by Inventor Takuya Aoki

Takuya Aoki 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: 20070181847
    Abstract: It is an object to provide a ferrite material which has a higher saturation magnetic flux density and low core loss, both at 100° C. The ferrite material is composed of a sintered body containing Fe, Mn and Zn as main constituents at x, y and z % by mol in terms of Fe2O3, MnO and ZnO, respectively, and containing Li as an additive at v % by weight in terms of Li2CO3 based on the main constituents, wherein x=55.7 to 60, z=3 to 8.5, y=100?x?z, v=0.3 to 0.8, and x1?x?x2 (x1=52.9?0.1z+8.5v and x2=54.4?0.1z+8.5v).
    Type: Application
    Filed: February 6, 2007
    Publication date: August 9, 2007
    Applicant: TDK CORPORATION
    Inventors: Tomofumi Kuroda, Isao Nakahata, Masahiko Watanabe, Masahito Furukawa, Osamu Hasegawa, Takuya Aoki
  • Patent number: 7238298
    Abstract: An Ni—Cu—Zn-based ferrite material contains TiO2 alone as an additive in an amount of 0.1 wt %<x?4.0 wt % in which x denotes a content of the TiO2 and unavoidable impurities. The principal components thereof are 43.0 to 49.8 mol % of Fe2O3, 4.0 to 13.0 mol % of CuO, 5 to 35 mol % of ZnO and the balance of NiO.
    Type: Grant
    Filed: October 6, 2004
    Date of Patent: July 3, 2007
    Assignee: TDK Corporation
    Inventors: Takuya Aoki, Taku Murase
  • Publication number: 20070138431
    Abstract: An NiCuZn-base ferrite of the invention comprises as main components an iron oxide in an amount of 45.0 to 49.0 mol % on Fe2O3 basis, an copper oxide in an amount of 5.0 to 14.0 mol % on CuO basis and a zinc oxide in an amount of 1.0 to 32.0 mol % on ZnO basis with a nickel oxide accounting for the rest mol % on NiO basis. With respect to the main components, a bismuth oxide is contained in an amount of 0.25 exclusive to 0.40% by weight on Bi2O3 basis, and a tin oxide is contained in an amount of 1.00 to 2.50% by weight on SnO2 basis. The invention ensures a leap upward in direct-current bias characteristics.
    Type: Application
    Filed: August 30, 2006
    Publication date: June 21, 2007
    Applicant: TDK CORPORATION
    Inventors: Ryuichi Wada, Takuya Aoki, Hiroshi Momoi, Yukio Takahashi, Takahiro Satoh
  • Publication number: 20060116283
    Abstract: A ferrite material of the present invention is configured such that 0.05 to 1.0 wt % of bismuth oxide in terms of Bi2O3, 0.5 to 3.0 wt % of tin oxide in terms of SnO2, and 30 to 5000 wt ppm of chromium oxide in terms of Cr2O3 are added to a predetermined main component mixture composition. Therefore, it is possible to achieve an improvement in DC bias characteristics, an improvement in temperature characteristics of initial magnetic permeability, and an improvement in resistivity and further achieve an improvement in burned body strength, particularly in burned body flexural strength (bending strength).
    Type: Application
    Filed: October 26, 2005
    Publication date: June 1, 2006
    Applicant: TDK Corporation
    Inventors: Ryuichi Wada, Takuya Aoki, Atsuhito Matsukawa, Kensaku Asakura
  • Patent number: 7034649
    Abstract: A ferrite material having a high Q value and also having a small absolute value of ??ir in a wide temperature range between ?40° C. and 160° C. A ferrite material, which comprises, as main constituents, 45.5 to 48 mol % of Fe2O3, 5 to 10.5 mol % of CuO, 26 to 30 mol % of ZnO, and the balance substantially being NiO, and further comprises, as an additive, cobalt oxide within a range between 0.005 and 0.045 wt % in terms of CoO. The ferrite material of the present invention has properties such as each of the absolute value of ??ir?40˜20 and the absolute value of ??ir20˜160 of 3 ppm/° C. or less, and a Q value at 125 kHz of 170 or more.
    Type: Grant
    Filed: August 31, 2004
    Date of Patent: April 25, 2006
    Assignee: TDK Corporation
    Inventors: Kensaku Asakura, Takuya Aoki, Taku Murase
  • Publication number: 20050258393
    Abstract: The temperature properties of the initial permeability of a Ni—Cu—Zn based ferrite material are improved while the degradation of the magnetic properties of the ferrite material is being suppressed. The ferrite material is formed of a sintered body comprising, as main constituents, Fe2O3: 47.0 to 50.0 mol %, CuO: 0 to 7 mol %, NiO: 13 to 26 mol %, and ZnO substantially constituting the balance, wherein the sintered body comprises 40 ppm or less of P in terms of P2O5 and 50 to 1800 ppm of one or more additives of Al2O3, CaO and MgO in relation to the sum of the contents of the main constituents. In the Ni—Cu—Zn based ferrite material, the mean grain size can be set at 12 ?m or less and the standard deviation of the grain size can be set at 4.5 ?m or less.
    Type: Application
    Filed: May 19, 2005
    Publication date: November 24, 2005
    Inventors: Shin Takane, Takuya Aoki
  • Publication number: 20050238904
    Abstract: There is provided a Mn—Zn based ferrite member excellent in mass productivity, high in withstand voltage, low in loss and excellent in direct current superposition property. The Mn—Zn based ferrite member is provided with a surface layer portion having the properties that ?5 defined in the specification satisfies the relation that ?5?103 ?m and ?50 defined in the specification satisfies the relation that ?50?102 ?m.
    Type: Application
    Filed: April 21, 2005
    Publication date: October 27, 2005
    Inventors: Takashi Kajino, Kenya Takagawa, Taku Murase, Takuya Aoki
  • Publication number: 20050199851
    Abstract: An Ni—Cu—Zn-based ferrite material contains TiO2 alone as an additive in an amount of 0.1 wt %<x?4.0 wt % in which x denotes a content of the TiO2 and unavoidable impurities. The principal components thereof are 43.0 to 49.8 mol % of Fe2O3, 4.0 to 13.0 mol % of CuO, 5 to 35 mol % of ZnO and the balance of NiO.
    Type: Application
    Filed: October 6, 2004
    Publication date: September 15, 2005
    Applicant: TDK CORPORATION
    Inventors: Takuya Aoki, Taku Murase
  • Publication number: 20050062576
    Abstract: A ferrite material having a high Q value and also having a small absolute value of ??ir in a wide temperature range between ?40° C. and 160° C. A ferrite material, which comprises, as main constituents, 45.5 to 48 mol % of Fe2O3, 5 to 10.5 mol % of CuO, 26 to 30 mol % of ZnO, and the balance substantially being NiO, and further comprises, as an additive, cobalt oxide within a range between 0.005 and 0.045 wt % in terms of CoO. The ferrite material of the present invention has properties such as each of the absolute value of ??ir?40˜20 and the absolute value of ??ir20˜160 of 3 ppm/° C. or less, and a Q value at 125 kHz of 170 or more.
    Type: Application
    Filed: August 31, 2004
    Publication date: March 24, 2005
    Inventors: Kensaku Asakura, Takuya Aoki, Taku Murase
  • Patent number: 6790379
    Abstract: A magnetic ferrite composition including at least one of Mg, Ni, Cu, Zn, Mn, and Li and having a content of carbon within a predetermined range, for example, over 9.7 weight ppm to less than 96 weight ppm. The composition may be used as the magnetic core for an inductor, transformer, coil, etc. used for radios, televisions, communication devices, office automation equipment, switching power sources, and other electronic apparatuses or magnetic heads for video apparatuses or magnetic disk drives or other electronic components.
    Type: Grant
    Filed: September 12, 2003
    Date of Patent: September 14, 2004
    Assignee: TDK Corporation
    Inventors: Takuya Aoki, Takeshi Nomura
  • Patent number: 6736990
    Abstract: There can be provided an NiCuZn-based ferrite material containing an iron oxide, a copper oxide, zinc oxide and a nickel oxide in predetermined amounts as main components and a bismuth oxide, a silicon oxide, magnesium oxide and a cobalt oxide in predetermined amounts as additional components. Due to the predetermined amounts of the additional components, the ferrite material has an extremely good temperature characteristic (a change in permeability along with a change in temperature is small), a high quality coefficient Q and high strength.
    Type: Grant
    Filed: March 7, 2002
    Date of Patent: May 18, 2004
    Assignee: TDK Corporation
    Inventors: Takuya Aoki, Ko Ito, Bungo Sakurai, Yukio Takahashi, Tatsuya Shimazaki, Hidenobu Umeda, Akinori Ohi
  • Publication number: 20040051075
    Abstract: A magnetic ferrite composition including at least one of Mg, Ni, Cu, Zn, Mn, and Li and having a content of carbon within a predetermined range, for example, over 9.7 weight ppm to less than 96 weight ppm. The composition may be used as the magnetic core for an inductor, transformer, coil, etc. used for radios, televisions, communication devices, office automation equipment, switching power sources, and other electronic apparatuses or magnetic heads for video apparatuses or magnetic disk drives or other electronic components.
    Type: Application
    Filed: September 12, 2003
    Publication date: March 18, 2004
    Applicant: TDK Corporation
    Inventors: Takuya Aoki, Takeshi Nomura
  • Patent number: 6652768
    Abstract: A magnetic ferrite composition including at least one of Mg, Ni, Cu, Zn, Mn, and Li and having a content of carbon within a predetermined range, for example, over 9.7 weight ppm to less than 96 weight ppm. The composition may be used as the magnetic core for an inductor, transformer, coil, etc. used for radios, televisions, communication devices, office automation equipment, switching power sources, and other electronic apparatuses or magnetic heads for video apparatuses or magnetic disk drives or other electronic components.
    Type: Grant
    Filed: October 10, 2002
    Date of Patent: November 25, 2003
    Assignee: TDK Corporation
    Inventors: Takuya Aoki, Takeshi Nomura
  • Publication number: 20030038273
    Abstract: A magnetic ferrite composition including at least one of Mg, Ni, Cu, Zn, Mn, and Li and having a content of carbon within a predetermined range, for example, over 9.7 weight ppm to less than 96 weight ppm. The composition may be used as the magnetic core for an inductor, transformer, coil, etc. used for radios, televisions, communication devices, office automation equipment, switching power sources, and other electronic apparatuses or magnetic heads for video apparatuses or magnetic disk drives or other electronic components.
    Type: Application
    Filed: October 10, 2002
    Publication date: February 27, 2003
    Applicant: TDK Corporation
    Inventors: Takuya Aoki, Takeshi Nomura
  • Patent number: 6495059
    Abstract: A magnetic ferrite composition including at least one of Mg, Ni, Cu, Zn, Mn, and Li and having a content of carbon within a predetermined range, for example, over 9.7 weight ppm to less than 96 weight ppm. The composition may be used as the magnetic core for an inductor, transformer, coil, etc. used for radios, televisions, communication devices, office automation equipment, switching power sources, and other electronic apparatuses or magnetic heads for video apparatuses or magnetic disk drives or other electronic components.
    Type: Grant
    Filed: September 13, 2000
    Date of Patent: December 17, 2002
    Assignee: TDK Corporation
    Inventors: Takuya Aoki, Takeshi Nomura
  • Publication number: 20020175311
    Abstract: There can be provided an NiCuZn-based ferrite material containing an iron oxide, a copper oxide, zinc oxide and a nickel oxide in predetermined amounts as main components and a bismuth oxide, a silicon oxide, magnesium oxide and a cobalt oxide in predetermined amounts as additional components. Due to the predetermined amounts of the additional components, the ferrite material has an extremely good temperature characteristic (a change in permeability along with a change in temperature is small), a high quality coefficient Q and high strength.
    Type: Application
    Filed: March 7, 2002
    Publication date: November 28, 2002
    Inventors: Takuya Aoki, Ko Ito, Bungo Sakurai, Yukio Takahashi, Tatsuya Shimazaki, Hidenoru Umeda, Akinori Ohi
  • Patent number: 6200493
    Abstract: There is disclosed an MnMgCuZn ferrite material which contains ranges of 46.5 to 50.4 mol % of iron oxide, 10.5 to 22.0 mol % of magnesium oxide, 22.5 to 25.0 mol % of zinc oxide, 6.0 to 16.0 mol % of copper oxide, and 0.1 to 3.5 mol % of manganese oxide. Advantages of an MnMgCuZn ferrite material that resistivity is relatively high and material cost is low are utilized to realize a superior MnMgCuZn ferrite material which is much smaller in magnetic loss than conventional materials of the same series and which has a sufficient saturated magnetic flux density.
    Type: Grant
    Filed: March 18, 1999
    Date of Patent: March 13, 2001
    Assignee: TDK Corporation
    Inventors: Taku Murase, Takuya Aoki, Naoyoshi Sato, Isao Kanada
  • Patent number: 6113843
    Abstract: The process for the preparation of an oxide magnetic compact of the invention comprises:a step of preparing a mixed material which comprises 44 to 50 mole % of iron calculated as Fe.sub.2 O.sub.3, 0.1 to 8 mole % of manganese calculated as Mn.sub.2 O.sub.3, with the sum of iron and manganese being 50 to 54 mole % calculated as Fe.sub.2 O.sub.3 and Mn.sub.2 O.sub.3, 20 to 38 mole % of magnesium calculated as MgO, 17 to 22 mole % of zinc calculated as ZnO and not more than 5 mole % of copper calculated as CuO, anda step of molding the aforesaid mixed material to a predetermined shape and then firing it in an atmosphere of low oxygen concentration of 2.5 to 12% by volume. Therefore, there appears an extremely excellent effect that the oxide magnetic compact having excellent electromagnetic properties can be obtained at low cost.
    Type: Grant
    Filed: March 23, 1999
    Date of Patent: September 5, 2000
    Assignee: TDK Corporation
    Inventors: Takuya Aoki, Taku Murase, Kazuhiro Takakura, Jun Sawai, Naoyoshi Sato
  • Patent number: 6031213
    Abstract: An electrode structure includes: a metallic electrode; a case for accommodating and holding the electrode, and one end of a lead wire connecting to the electrode; and an insulating member interposed between the electrode and the case in order to ensure insulation between the electrode and the case, in which structure a waterproof member is interposed between the case and the lead wire in order to prevent the incoming of water from between the case and the lead wire, and an electric heater havinging the above electrode structure.
    Type: Grant
    Filed: December 5, 1995
    Date of Patent: February 29, 2000
    Assignees: NGK Insulators, Ltd., Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Shigeharu Hashimoto, Tadato Ito, Yuichi Shimasaki, Hiroaki Kato, Takashi Komatsuda, Akihisa Saito, Takuya Aoki, Tetsu Teshirogi
  • Patent number: 6028353
    Abstract: The present invention relates to a laminated chip bead element demonstrating noise absorption characteristics over a broad range in a high frequency range of GHz or higher. An insulating body is constituted of a material achieved by mixing ferrite powder and an insulating resin. At least one signal conductor is embedded in the insulating body. It is desirable that the insulating body includes a plurality of composite members.
    Type: Grant
    Filed: August 11, 1998
    Date of Patent: February 22, 2000
    Assignee: TDK Corporation
    Inventors: Atsuyuki Nakano, Akinori Oi, Takuya Aoki, Minoru Takaya