Patents by Inventor Dai Matsuoka

Dai Matsuoka 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: 7995326
    Abstract: A chip-type electronic component has: a ceramic element body; a plurality of first and second internal electrodes arranged in the ceramic element body so as to be opposed at least in part to each other; a first external connection conductor to which the plurality of first internal electrodes are connected; a second external connection conductor to which the plurality of second internal electrodes are connected; first and second terminal electrodes; a first internal connection conductor arranged in the ceramic element body and connecting the first external connection conductor and the first terminal electrode; and a second internal connection conductor arranged in the ceramic element body and connecting the second external connection conductor and the second terminal electrode.
    Type: Grant
    Filed: May 21, 2009
    Date of Patent: August 9, 2011
    Assignee: TDK Corporation
    Inventors: Kaname Ueda, Dai Matsuoka, Naoki Chida, Izuru Soma, Hisayoshi Saito, Katsunari Moriai
  • Patent number: 7994893
    Abstract: A varistor has a ceramic composition to exhibit nonlinear voltage-current characteristics, and at least two electrodes arranged to sandwich at least a portion of the ceramic composition. The ceramic composition contains a mixture phase in which a first phase containing zinc oxide as a major component, and a second phase comprised of an oxide of Ca and Si are mixed.
    Type: Grant
    Filed: July 8, 2008
    Date of Patent: August 9, 2011
    Assignee: TDK Corporation
    Inventor: Dai Matsuoka
  • Patent number: 7969277
    Abstract: A nonlinear resistor ceramic composition has a major component containing zinc oxide, a first minor component containing an oxide of a rare-earth metal, a second minor component containing an oxide of Ca, and a third minor component containing an oxide of Si. A percentage of the second minor component to 100 moles of the major component is in the range of 2 atomic %?the second minor component<80 atomic % in terms of Ca. A percentage of the third minor component to 100 moles of the major component is in the range of 1 atomic %?the third minor component<40 atomic % in terms of Si. An atomic ratio of Ca to Si (Ca/Si) is not less than 1.
    Type: Grant
    Filed: July 8, 2008
    Date of Patent: June 28, 2011
    Assignee: TDK Corporation
    Inventor: Dai Matsuoka
  • Publication number: 20110141638
    Abstract: The electrostatic protection device in accordance with the present invention is the electrostatic protection device for protecting a plurality of electronic elements electrically connected in series against static electricity, the device comprising a plurality of first electrostatic protection elements having a current-voltage nonlinear resistance characteristic, a plurality of second electrostatic protection elements having a current-voltage nonlinear resistance characteristic, and a ground terminal for electrically connecting with a ground. The plurality of first electrostatic protection elements are electrically connected in parallel to the respective electronic elements, while the plurality of second electrostatic protection elements are electrically connected between input terminals of the respective electronic elements and the ground terminal.
    Type: Application
    Filed: December 10, 2010
    Publication date: June 16, 2011
    Applicant: TDK CORPORATION
    Inventors: Yousuke HOSHIKAWA, Mikio TSURUOKA, Hiroyuki SATO, Goro TAKEUCHI, Dai MATSUOKA
  • Patent number: 7754109
    Abstract: In a varistor element, Ca exists in the grain interior of grains consisting primarily of ZnO in a varistor element body and Ca also exists in a grain boundary. In this crystal structure Ca replaces oxygen defects in the grain interior of grains consisting primarily of ZnO, in the varistor element body to make the ceramic structure denser Such crystal structure also decreases a ratio of an element tending to degrade the stability of the temperature characteristic of the varistor element, e.g., Si as a firing aid, in the grain boundary between grains. As a result, the varistor element has a stable temperature characteristic, which can decrease change in capacitance and tan ? (thermal conversion factor of resistance) against change in temperature.
    Type: Grant
    Filed: February 25, 2008
    Date of Patent: July 13, 2010
    Assignee: TDK Corporation
    Inventors: Naoyoshi Yoshida, Hitoshi Tanaka, Dai Matsuoka
  • Patent number: 7724123
    Abstract: A varistor is provided with a varistor element, and an external electrode disposed on the varistor element. The varistor element contains ZnO as a principal ingredient and contains a rare-earth element and Ca. The external electrode is formed by baking on an outer surface of the varistor element and contains Pt. When the external electrode is formed by baking on the varistor element, a compound of the rare-earth element and Pt and a compound of Ca and Pt are formed near an interface between the varistor element and the external electrode, and exist there. The existence of these compounds enhances the bonding strength between the varistor element and the external electrode.
    Type: Grant
    Filed: November 13, 2006
    Date of Patent: May 25, 2010
    Assignee: TDK Corporation
    Inventors: Dai Matsuoka, Yo Saito, Izuru Soma, Hideaki Sone
  • Patent number: 7705708
    Abstract: A varistor has a varistor element body, and an external electrode disposed on the varistor element body. The varistor element body contains ZnO as a principal component, and a rare-earth metal. The external electrode has an electrode layer. The electrode layer is formed on an external surface of the varistor element body by simultaneous firing with the varistor element body. The electrode layer contains Pd.
    Type: Grant
    Filed: March 27, 2006
    Date of Patent: April 27, 2010
    Assignee: TDK Corporation
    Inventors: Dai Matsuoka, Yo Saito
  • Patent number: 7683753
    Abstract: As for the voltage non-linear resistance element layer 2, sintered body (ceramics) having ZnO as main component is used. Said sintered body comprises Pr, Co, Ca and Na are added. Therefore, the ranges are 0.05 to 5.0 atm % of Pr, 0.1 to 20 atm % of Co, 0.01 to 5.0 atm % of Ca and 0.0001 to 0.0008 atm % of Na. When it is within the range, the capacitance changing rate at 85° C. with standard being 25° C. can be made to equal or less than 10%.
    Type: Grant
    Filed: March 25, 2008
    Date of Patent: March 23, 2010
    Assignee: TDK Corporation
    Inventors: Naoyoshi Yoshida, Hitoshi Tanaka, Dai Matsuoka
  • Patent number: 7652554
    Abstract: An object of the present invention is to provide a multilayer filter constructed so as to be less likely to suffer peeling between a varistor part and an inductor part. A multilayer filter 10 as a preferred embodiment has a structure in which a varistor part 20 and an inductor part are stacked. The varistor part 30 consists of a stack of varistor layers 31, 32 with internal electrodes 31a, 32a, and the varistor layers contain ZnO as a principal component, and contain at least one element selected from the group consisting of Pr and Bi, Co, and Al as additives. The inductor part 20 consists of a stack of inductor layers 21-24 with conductor patterns 21a-24a, and the inductor layers contain ZnO as a principal component and substantially contain neither Co nor Al.
    Type: Grant
    Filed: May 1, 2006
    Date of Patent: January 26, 2010
    Assignee: TDK Corporation
    Inventors: Katsunari Moriai, Dai Matsuoka, Takahiro Sato
  • Patent number: 7649435
    Abstract: A multilayer chip varistor comprises a multilayer body in which a plurality of varistor portions are arranged along a predetermined direction, and a plurality of terminal electrodes. Each varistor portion has a varistor layer to exhibit nonlinear voltage-current characteristics, and a plurality of internal electrodes disposed so as to interpose the varistor layer between them. Each terminal electrode is disposed on a first outer surface parallel to the predetermined direction out of outer surfaces of the multilayer body and is electrically connected to a corresponding internal electrode out of the plurality of internal electrodes. Each of the plurality of internal electrodes includes a first electrode portion overlapping with another first electrode portion between adjacent internal electrodes out of the plurality of internal electrodes, and a second electrode portion led from the first electrode portion so as to be exposed in the first outer surface.
    Type: Grant
    Filed: March 28, 2006
    Date of Patent: January 19, 2010
    Assignee: TDK Corporation
    Inventors: Katsunari Moriai, Dai Matsuoka, Yo Saito
  • Patent number: 7646578
    Abstract: A filter circuit has first and second varistors, a resistance, an input terminal, an output terminal, and a ground terminal. The resistance is connected between the first and second varistors. The input terminal is connected to a junction between the first varistor and resistance through a first coil. The output terminal is connected to a junction between the second varistor and resistance through a second coil. The ground terminal is connected to a side of the first varistor opposite from the resistance and a side of the second varistor opposite from the resistance.
    Type: Grant
    Filed: April 16, 2007
    Date of Patent: January 12, 2010
    Assignee: TDK Corporation
    Inventors: Yuji Terada, Dai Matsuoka, Koichi Ishii
  • Patent number: 7639470
    Abstract: A varistor element comprises a varistor element body, a plurality of inner electrode pairs, a connecting conductor, and a plurality of terminal electrodes. The varistor element body has first and second main faces opposing each other. Each inner electrode pair has first and second inner electrodes. The first and second inner electrodes are arranged so as to oppose each other at least partly within the varistor element body. The connecting conductor is arranged on the first main face so as to electrically connect the first inner electrodes in a predetermined inner electrode pair in the plurality of inner electrode pairs to each other. The terminal electrodes are provided so as to correspond to the second inner electrodes in the plurality of inner electrode pairs, and are arranged on the second main face so as to electrically connect with the second inner electrodes.
    Type: Grant
    Filed: November 29, 2006
    Date of Patent: December 29, 2009
    Assignee: TDK Corporation
    Inventors: Yo Saito, Dai Matsuoka, Izuru Soma, Hideaki Sone
  • Publication number: 20090296312
    Abstract: A chip-type electronic component has: a ceramic element body; a plurality of first and second internal electrodes arranged in the ceramic element body so as to be opposed at least in part to each other; a first external connection conductor to which the plurality of first internal electrodes are connected; a second external connection conductor to which the plurality of second internal electrodes are connected; first and second terminal electrodes; a first internal connection conductor arranged in the ceramic element body and connecting the first external connection conductor and the first terminal electrode; and a second internal connection conductor arranged in the ceramic element body and connecting the second external connection conductor and the second terminal electrode.
    Type: Application
    Filed: May 21, 2009
    Publication date: December 3, 2009
    Applicant: TDK CORPORATION
    Inventors: Kaname Ueda, Dai Matsuoka, Naoki Chida, Izuru Soma, Hisayoshi Saito, Katsunari Moriai
  • Patent number: 7576965
    Abstract: An object of the present invention is to provide a small surge absorption element that exhibits superior impedance matching even for high-speed signals and a surge absorption circuit. The surge absorption element comprises first and second inductor sections and first and second surge absorption sections. The first inductor section comprises first and second coils and the second inductor section comprises third and fourth coils. By suitably setting the coupling coefficients between the respective coils and the induction coefficients of the first to fourth coils, image impedance with an even frequency characteristic can be implemented over a wide area. Further, because the first to fourth coils have a positive magnetically coupled state with respect to one another, the induction coefficients of the first to fourth coils can be reduced in comparison with a case where the first to fourth coils are not afforded a positive magnetically coupled state.
    Type: Grant
    Filed: July 17, 2006
    Date of Patent: August 18, 2009
    Assignee: TDK Corporation
    Inventors: Yuji Terada, Dai Matsuoka, Naoki Chida
  • Patent number: 7507356
    Abstract: As for the voltage non-linear resistance element layer 2, a sintered body having ZnO as a main component is used. In this sintered body, Pr, Co, Ca, and either Cu or Ni are added. The ranges are; 0.05 to 5.0 atm % of Pr, 0.1 to 20 atm % of Co, 0.01 to 5.0 atm % of Ca, and 0.0005 to 0.05 atm % of either Cu or Ni. Within these ranges, the capacitance changing rate can be made to equal or less than 10 % at 85° C. when 25° C. is taken as standard.
    Type: Grant
    Filed: March 28, 2008
    Date of Patent: March 24, 2009
    Assignee: TDK Corporation
    Inventors: Naoyoshi Yoshida, Hitoshi Tanaka, Dai Matsuoka
  • Patent number: 7505239
    Abstract: A light emitting device has a semiconductor light emitting element and a multilayer chip varistor. The multilayer chip varistor has a multilayer body with a varistor portion therein, and a plurality of external electrodes disposed on an outer surface of the multilayer body. The varistor portion has a varistor layer containing ZnO as a principal component and exhibiting nonlinear voltage-current characteristics, and a plurality of internal electrodes arranged to interpose the varistor layer between them. Each of the external electrodes is connected to a corresponding internal electrode out of the plurality of internal electrodes. The semiconductor light emitting element is disposed on the multilayer chip varistor. The semiconductor light emitting element is connected to corresponding external electrodes out of the plurality of external electrodes so as to be connected in parallel to the varistor portion.
    Type: Grant
    Filed: April 13, 2006
    Date of Patent: March 17, 2009
    Assignee: TDK Corporation
    Inventors: Jitsuo Kanazawa, Nobuei Shimojo, Dai Matsuoka, Kimio Suto, Makoto Numata, Yo Saito
  • Patent number: 7502213
    Abstract: A surge absorber has a first terminal electrode, a second terminal electrode, a third terminal electrode, an inductor portion, a surge absorbing portion, and a capacitor portion. The inductor portion has a first internal conductor and a second internal conductor mutually coupled in a polarity-reversed relation. One end of the first internal conductor is connected to the first terminal electrode. One end of the second internal conductor is connected to the second terminal electrode. The other end of the first internal conductor is connected to the other end of the second internal conductor. The surge absorbing portion has a first internal electrode connected to a connection point between the first internal conductor and the second internal conductor, and a second internal electrode connected to the third terminal electrode. The capacitor portion has a capacitance component connected between the first terminal electrode and the second terminal electrode.
    Type: Grant
    Filed: June 9, 2006
    Date of Patent: March 10, 2009
    Assignee: TDK Corporation
    Inventors: Dai Matsuoka, Yuji Terada, Katsunari Moriai
  • Publication number: 20090021341
    Abstract: A varistor has a ceramic composition to exhibit nonlinear voltage-current characteristics, and at least two electrodes arranged to sandwich at least a portion of the ceramic composition. The ceramic composition contains a mixture phase in which a first phase containing zinc oxide as a major component, and a second phase comprised of an oxide of Ca and Si are mixed.
    Type: Application
    Filed: July 8, 2008
    Publication date: January 22, 2009
    Applicant: TDK CORPORATION
    Inventor: Dai MATSUOKA
  • Publication number: 20090015367
    Abstract: A nonlinear resistor ceramic composition has a major component containing zinc oxide, a first minor component containing an oxide of a rare-earth metal, a second minor component containing an oxide of Ca, and a third minor component containing an oxide of Si. A percentage of the second minor component to 100 moles of the major component is in the range of 2 atomic % ? the second minor component <80 atomic % in terms of Ca. A percentage of the third minor component to 100 moles of the major component is in the range of 1 atomic % ? the third minor component <40 atomic % in terms of Si. An atomic ratio of Ca to Si (Ca/Si) is not less than 1.
    Type: Application
    Filed: July 8, 2008
    Publication date: January 15, 2009
    Applicant: TDK CORPORATION
    Inventor: Dai MATSUOKA
  • Publication number: 20080308312
    Abstract: A ceramic electronic component comprises a ceramic element body and an outer electrode arranged on the ceramic element body. The outer electrode includes a first electrode layer and a second electrode layer formed on the first electrode layer. The first electrode layer is formed on an outer surface of the ceramic element body and contains Ag and a glass material. The second electrode layer contains Pt and has a plurality of holes reaching the first electrode layer at respective locations.
    Type: Application
    Filed: June 3, 2008
    Publication date: December 18, 2008
    Applicant: TDK CORPORATION
    Inventors: Izuru SOMA, Naoki CHIDA, Dai MATSUOKA, Miyuki YANAGIDA