Patents Assigned to Oita University
  • Publication number: 20190226552
    Abstract: In a vibration damping device 20, the moment of inertia J1 of a driven member 15, the moment of inertia J2 of an inertial mass body 23, the mass m of crank members 22, the distance L3 between the center of gravity G of the crank member 22 and the fulcrum of swinging of the crank member 22 with respect to the inertial mass body 23, and the distance L4 between this fulcrum and the center of rotation RC are determined so that torque fluctuation of an object for which vibration is to be damped, which is derived based on angular displacement and angles obtained by solving an equation of motion for the driven member 15 and an equation of motion for the entire vibration damping device 20 is equal to a target value.
    Type: Application
    Filed: September 29, 2017
    Publication date: July 25, 2019
    Applicants: AISIN AW CO., LTD., NATIONAL UNIVERSITY CORPORATION OITA UNIVERSITY, Kagoshima University
    Inventors: Yoichi OI, Masaki WAJIMA, Hiroki NAGAI, Takao SAKAMOTO, Takahiro RYU, Takashi NAKAE, Kenichiro MATSUZAKI
  • Patent number: 10284075
    Abstract: An overvoltage protection circuit is provided which is connected between a rectifier circuit and a load including an input capacitor element connected to both ends of the load. The overvoltage protection circuit includes a semiconductor switch connected between the rectifier circuit and the load, and a control circuit controls the semiconductor switch. When the rectified voltage exceeds a predetermined value, the control circuit turns off the semiconductor switch, and detects a voltage potential difference between both ends of the semiconductor switch, and then, for an interval when the voltage potential difference is zero or a predetermined minute value, the control circuit generates a control voltage for turning on the semiconductor switch, and outputs the control voltage to a control terminal of the semiconductor switch. The overvoltage protection circuit includes a current change circuit that gradually changes a current flowing through the semiconductor switch.
    Type: Grant
    Filed: August 1, 2018
    Date of Patent: May 7, 2019
    Assignees: RICOH ELECTRONIC DEVICES CO., LTD., NATIONAL UNIVERSITY CORPORATION OITA UNIVERSITY
    Inventors: Shohtaroh Sohma, Yuji Takeyama, Kimihiro Nishijima
  • Publication number: 20190058323
    Abstract: An overvoltage protection circuit is provided which is connected between a rectifier circuit and a load including an input capacitor element connected to both ends of the load. The overvoltage protection circuit includes a semiconductor switch connected between the rectifier circuit and the load, and a control circuit controls the semiconductor switch. When the rectified voltage exceeds a predetermined value, the control circuit turns off the semiconductor switch, and detects a voltage potential difference between both ends of the semiconductor switch, and then, for an interval when the voltage potential difference is zero or a predetermined minute value, the control circuit generates a control voltage for turning on the semiconductor switch, and outputs the control voltage to a control terminal of the semiconductor switch. The overvoltage protection circuit includes a current change circuit that gradually changes a current flowing through the semiconductor switch.
    Type: Application
    Filed: August 1, 2018
    Publication date: February 21, 2019
    Applicants: RICOH ELECTRONIC DEVICES CO., LTD., NATIONAL UNIVERSITY CORPORATION OITA UNIVERSITY
    Inventors: Shohtaroh SOHMA, Yuji TAKEYAMA, Kimihiro NISHIJIMA
  • Patent number: 10192669
    Abstract: A vector-magnetic-property-controlling material according to the present embodiment is subjected to a scratching process in two directions that intersect on the surface of a steel material. An iron core according to the present embodiment is configured from an oriented magnetic steel material which has been subjected to a scratching process in two directions that intersect on the surface thereof.
    Type: Grant
    Filed: November 21, 2014
    Date of Patent: January 29, 2019
    Assignees: TOSHIBA INDUSTRIAL PRODUCTS & SYSTEMS CORPORATION, NATIONAL UNIVERSITY CORPORATION OITA UNIVERSITY
    Inventors: Masato Enokizono, Hiromu Shiota, Eiji Shimomura, Tsuyoshi Masuda
  • Publication number: 20180187744
    Abstract: A vibration damping device 20 includes: a crank member 22 that is coupled to a driven member 15 via a first coupling shaft A1 and that is swingable about the first coupling shaft A1 along with rotation of the driven member 15; and an inertial mass body 24 that is coupled to the driven member 15 via the crank member 22 and a connecting rod 23 and that is swung about a center of rotation RC in conjunction with the crank member 22 along with rotation of the driven member 15. A component force of a centrifugal force that acts on the crank member 22 along with rotation of the driven member 15 in a direction that is orthogonal to the direction from the center of the first coupling shaft A1 toward the center of gravity G always acts on the crank member 22 as a restoring force that acts to return the inertial mass body 24 to the center of the swing range. The component force is maximum when the inertial mass body 24 is positioned at the center of the swing range.
    Type: Application
    Filed: July 15, 2016
    Publication date: July 5, 2018
    Applicants: AISIN AW CO., LTD., NATIONAL UNIVERSITY CORPORATION OITA UNIVERSITY, KAGOSHIMA UNIVERSITY
    Inventors: Yoshihiro TAKIKAWA, Hiroki NAGAI, Masaki WAJIMA, Takao SAKAMOTO, Takahiro RYU, Takashi NAKAE, Kenichiro MATSUZAKI
  • Patent number: 9962683
    Abstract: The present invention provides an alloy fine particle including palladium and ruthenium, the alloy fine particle including at least one first phase in which the palladium is more abundant than the ruthenium and at least one second phase in which the ruthenium is more abundant than the palladium, the at least one first phase and the at least one second phase being separated by a phase boundary, the palladium and the ruthenium being distributed in the phase boundary in such a manner that the molar ratio of the palladium and the ruthenium continually changes, a plurality of crystalline structures being present together in the phase boundary.
    Type: Grant
    Filed: September 9, 2015
    Date of Patent: May 8, 2018
    Assignees: Kyoto University, OITA UNIVERSITY, KYUSHU UNIVERSITY, NATIONAL UNIVERSITY CORPORATION
    Inventors: Hiroshi Kitagawa, Kohei Kusada, Hirokazu Kobayashi, Katsutoshi Nagaoka, Katsutoshi Sato, Syo Matsumura, Tomokazu Yamamoto
  • Patent number: 9960678
    Abstract: In a power converter, a first electrical path connects between the series resonant circuit and a selected terminal from the high- and low-side input and output terminals of the power converter. An auxiliary diode is provided on one of the series resonant circuit and the first electrical path. An auxiliary switch, when turned on, causes an inductor current to flow through the auxiliary diode to the resonance inductor, thus storing electromagnetic energy into the resonance inductor, and causes the resonance inductor and the capacitance component of the series resonant circuit to resonate with each other. A second electrical path bypasses the auxiliary switch for flow of the inductor current. A discharge unit is provided on the second electrical path. The discharge unit is activated to discharge the electromagnetic energy stored in the resonance inductor via the second electrical path.
    Type: Grant
    Filed: June 21, 2017
    Date of Patent: May 1, 2018
    Assignees: DENSO CORPORATION, NATIONAL UNIVERSITY CORPORATION OITA UNIVERSITY
    Inventors: Eisuke Takahashi, Masaya Takahashi, Kimihiro Nishijima
  • Patent number: 9919926
    Abstract: The present invention provides a method for producing a random-structure GIC in which exfoliated graphite having a low regularity of a graphene stacked state and a small number of stacked graphene layers can be easily obtained by exfoliation treatment. The method includes the steps of providing an alkali metal-GIC having an alkali metal intercalated between graphene layers and bringing a polar protic solvent into contact with the alkali metal-GIC in a non-oxidizing atmosphere.
    Type: Grant
    Filed: March 4, 2014
    Date of Patent: March 20, 2018
    Assignees: SEKISUI CHEMICAL CO., LTD., OITA UNIVERSITY
    Inventors: Takuya Wada, Akira Nakasuga, Masahiro Toyoda
  • Publication number: 20180051975
    Abstract: An apparatus is provided to measure a depth of a hardened layer formed at a surface layer of a quenched workpiece. The apparatus includes an exciting coil configured to generate a magnetic flux to magnetize the workpiece and a detecting coil configured to detect the magnetic flux generated by the exciting coil. The exciting coil has a U-shaped excitation core portion and an excitation coil portion wound on the excitation core portion. The excitation core portion is arranged such that distal ends of magnetic poles of the excitation core portion face the workpiece. The detecting coil has a detection core portion and a detection coil wound on the detection core portion. The detection core portion is arranged between the magnetic poles of the excitation core portion and along a surface of the workpiece.
    Type: Application
    Filed: March 2, 2016
    Publication date: February 22, 2018
    Applicants: NETUREN CO., LTD., OITA UNIVERSITY
    Inventors: Yoshitaka MISAKA, Kazuhiro KAWASAKI, Kenta SAKURAI, Yuji GOTOH
  • Publication number: 20170373592
    Abstract: In a power converter, a first electrical path connects between the series resonant circuit and a selected terminal from the high- and low-side input and output terminals of the power converter. An auxiliary diode is provided on one of the series resonant circuit and the first electrical path. An auxiliary switch, when turned on, causes an inductor current to flow through the auxiliary diode to the resonance inductor, thus storing electromagnetic energy into the resonance inductor, and causes the resonance inductor and the capacitance component of the series resonant circuit to resonate with each other. A second electrical path bypasses the auxiliary switch for flow of the inductor current. A discharge unit is provided on the second electrical path. The discharge unit is activated to discharge the electromagnetic energy stored in the resonance inductor via the second electrical path.
    Type: Application
    Filed: June 21, 2017
    Publication date: December 28, 2017
    Applicants: DENSO CORPORATION, NATIONAL UNIVERSITY CORPORATION OITA UNIVERSITY
    Inventors: Eisuke TAKAHASHI, Masaya TAKAHASHI, Kimihiro NISHIJIMA
  • Publication number: 20170259247
    Abstract: The present invention provides an alloy fine particle including palladium and ruthenium, the alloy fine particle including at least one first phase in which the palladium is more abundant than the ruthenium and at least one second phase in which the ruthenium is more abundant than the palladium, the at least one first phase and the at least one second phase being separated by a phase boundary, the palladium and the ruthenium being distributed in the phase boundary in such a manner that the molar ratio of the palladium and the ruthenium continually changes, a plurality of crystalline structures being present together in the phase boundary.
    Type: Application
    Filed: September 9, 2015
    Publication date: September 14, 2017
    Applicants: Kyoto University, OITA UNIVERSITY, KYUSHU UNIVERSITY, NATIONAL UNIVERSITY CORPORATION
    Inventors: Hiroshi KITAGAWA, Kohei KUSADA, Hirokazu KOBAYASHI, Katsutoshi NAGAOKA, Katsutoshi SATO, Syo MATSUMURA, Tomokazu YAMAMOTO
  • Publication number: 20170237332
    Abstract: In a power converter, switch-off of the synchronous rectification switch while the auxiliary switch is on causes the first capacitance of the main switch and the second capacitance of the synchronous rectification switch to resonate with the inductance of the second magnetic component. A parameter obtainer detects a voltage across a selected one of the main switch and the synchronous rectification switch, and obtains a parameter indicative of a corresponding one of rising and falling waveforms of the voltage across the selected switch while the selected switch is switched. A controller controls a switching control signal for the auxiliary switch to adjust switch-on timing of the auxiliary switch as a function of the parameter obtained by the parameter obtainer.
    Type: Application
    Filed: February 16, 2017
    Publication date: August 17, 2017
    Applicants: DENSO CORPORATION, NATIONAL UNIVERSITY CORP. OITA UNIVERSITY
    Inventors: Masaya TAKAHASHI, Nobuhisa YAMAGUCHI, Kimihiro NISHIJIMA
  • Patent number: 9673465
    Abstract: The present invention provides a catalyst in which a reaction initiation temperature at which self-heating function is exhibited is low and which is capable of suppressing carbon accumulation even when a reaction is repeated. The catalyst of the present invention includes a CeZr-based oxide, silicon, and a catalytically active metal, wherein the CeZr-based oxide satisfies CexZryO2 (x+y=1) and the silicon satisfies molar ratios of 0.02?Si/Zr and 0.01<Si/(Ce+Zr+Si)<0.2. When the catalyst is used, a reduction temperature for generating initial oxygen deficiency can be decreased. Depending on the catalytically active metal, a reduction activation treatment can be performed even at about 20° C. without any need for heating. In a repeated hydrogen generating reaction, the deposition of carbon generated on the surface of the catalyst can be suppressed, and a decrease in catalytic activity can be prevented.
    Type: Grant
    Filed: March 7, 2013
    Date of Patent: June 6, 2017
    Assignees: OITA UNIVERSITY, DOWA HOLDINGS CO., LTD.
    Inventors: Katsutoshi Nagaoka, Tatsuro Miyazaki, Takuya Yano, Kazumasa Ikari, Toshihiko Ueyama
  • Patent number: 9304108
    Abstract: A quenching depth measuring method is used for measuring the quenching depth in a workpiece and includes the steps of: magnetizing the workpiece by disposing, in the vicinity of the workpiece, a magnetizer equipped with an exciting coil; detecting, through a detection coil, an induced magnetic field generated by the magnetization; measuring the induced magnetic field as the output voltage of the detection coil; and specifying the thickness of the quenched hardened layer of the workpiece on the basis of known electromagnetic characteristic information of an unquenched material and a fully-quenched material and an output voltage value measured by the detection coil, the unquenched material being made of the same material as the constituent material of the workpiece and being a material on which a quenching process is not performed, the fully-quenched material being a material on which the quenching process is performed.
    Type: Grant
    Filed: October 26, 2011
    Date of Patent: April 5, 2016
    Assignees: NETUREN CO., LTD., NATIONAL UNIVERSITY CORPORATION OITA UNIVERSITY
    Inventors: Yuji Gotoh, Noriyoshi Takaoka, Kazuhiro Kawasaki, Yoshitaka Misaka
  • Patent number: 9294076
    Abstract: A problem of the present invention is to provide a switching power supply device and a pulse width modulation circuit capable of operating stably in synchronization with a clock signal. To solve the problem, a pulse width modulation circuit 3A in a switching power supply device 1A includes square-wave voltage output means 8A for, when an integrated voltage Vn rises to an upper threshold voltage or more, shifting a square-wave voltage VPWM to L level, or when the voltage Vn drops to a lower threshold voltage or less, shifting the voltage VPWM to H level, and clock means 6A for outputting a first clock signal VCL1 and a second clock signal VCL2, which are 180° out of phase from each other.
    Type: Grant
    Filed: July 19, 2012
    Date of Patent: March 22, 2016
    Assignee: OITA UNIVERSITY
    Inventor: Terukazu Sato
  • Patent number: 9139489
    Abstract: Provided are a method of manufacturing an olefin having 2 to 4 carbon atoms including: reacting a catalyst with synthesis gas through a Fischer-Tropsch reaction, thereby obtaining the olefin having 2 to 4 carbon atoms, in which the catalyst is a catalyst obtained by reducing the iron ion and the cobalt ion in a dispersion liquid or a solution containing the iron ion, the cobalt ion and a dispersant that interacts with the iron ion and the cobalt ion, and a method of manufacturing propylene, which uses the above manufacturing method.
    Type: Grant
    Filed: August 8, 2013
    Date of Patent: September 22, 2015
    Assignees: SUMITOMO CHEMICAL COMPANY, LIMITED, Kyushu University, NATIONAL UNIVERSITY CORPORATION, NATIONAL UNIVERSITY CORPORATION OITA UNIVERSITY, NATIONAL UNIVERSITY CORPORATION UNIVERSITY OF TOYAMA
    Inventors: Miho Yamauchi, Katsutoshi Nagaoka, Katsutoshi Sato, Noritatsu Tsubaki, Akihiro Yuasa, Hideyuki Higashimura, Takeshi Ishiyama
  • Publication number: 20150246342
    Abstract: There is provided a catalyst for hydrocarbon reforming having a high deposition suppressing effect with respect to a carbonaceous material on the catalyst surface even in a case where a reforming material including carbon dioxide, in particular, formed of only carbon dioxide is used in a reforming reaction, a method of manufacturing the same, and a method of manufacturing a synthesis gas using the catalyst.
    Type: Application
    Filed: February 26, 2015
    Publication date: September 3, 2015
    Applicants: SUMITOMO CHEMICAL COMPANY, LIMITED, NATIONAL UNIVERSITY CORPORATION OITA UNIVERSITY, SHOEI CHEMICAL INC.
    Inventors: Kazuro NAGASHIMA, Katsutoshi NAGAOKA, Katsutoshi SATO, Hideyuki HIGASHIMURA
  • Patent number: 9073043
    Abstract: The drive of direct-heat-supply type reforming of hydrocarbon at ordinary temperature is necessary in order to realize a self-sustaining, on-site reforming type fuel cell system which does not necessitate the supply of energy from the outside. According to the invention, an oxide, CeO2 or Pr6O11, or a Ce/Zr or Ce/Zr/Y double oxide is used as the oxide containing a rare earth element capable of changing the oxidation number with an active metal and oxygen defects are introduced into the oxide or double oxide by activating the oxide or double oxide with a reducing gas at high temperature. When a reaction gas containing hydrocarbon and oxygen is passed though the catalyst at low temperature, the oxygen defects react with oxygen and thereby return to the original oxide.
    Type: Grant
    Filed: November 19, 2007
    Date of Patent: July 7, 2015
    Assignee: National University Corporation Oita University
    Inventors: Katutoshi Nagaoka, Yuusaku Takita, Katutoshi Satou, Hiroyasu Nishiguti
  • Publication number: 20150171448
    Abstract: The present invention provides a catalyst in which a reaction initiation temperature at which self-heating function is exhibited is low and which is capable of suppressing carbon accumulation even when a reaction is repeated. The catalyst of the present invention includes a CeZr-based oxide, silicon, and a catalytically active metal, wherein the CeZr-based oxide satisfies CexZryO2 (x+y=1) and the silicon satisfies molar ratios of 0.02?Si/Zr and 0.01<Si/(Ce+Zr+Si)<0.2. When the catalyst is used, a reduction temperature for generating initial oxygen deficiency can be decreased. Depending on the catalytically active metal, a reduction activation treatment can be performed even at about 20° C. without any need for heating. In a repeated hydrogen generating reaction, the deposition of carbon generated on the surface of the catalyst can be suppressed, and a decrease in catalytic activity can be prevented.
    Type: Application
    Filed: March 7, 2013
    Publication date: June 18, 2015
    Applicants: DOWA HOLDINGS CO., LTD., OITA UNIVERSITY
    Inventors: Katsutoshi Nagaoka, Tatsuro Miyazaki, Takuya Yano, Kazumasa Ikari, Toshihiko Ueyama
  • Publication number: 20140045955
    Abstract: Provided are a method of manufacturing an olefin having 2 to 4 carbon atoms including: reacting a catalyst with synthesis gas through a Fischer-Tropsch reaction, thereby obtaining the olefin having 2 to 4 carbon atoms, in which the catalyst is a catalyst obtained by reducing the iron ion and the cobalt ion in a dispersion liquid or a solution containing the iron ion, the cobalt ion and a dispersant that interacts with the iron ion and the cobalt ion, and a method of manufacturing propylene, which uses the above manufacturing method.
    Type: Application
    Filed: August 8, 2013
    Publication date: February 13, 2014
    Applicants: SUMITOMO CHEMICAL COMPANY , LIMITED, National University Corporation University of Toya ma, NATIONAL UNIVERSITY CORPORATION OITA UNIVERSITY, KYUSHU UNIVERSITY, NATIONAL UNIVERSITY CORPORATION
    Inventors: Miho YAMAUCHI, Katsutoshi NAGAOKA, Katsutoshi SATO, Noritatsu TSUBAKI, Akihiro YUASA, Hideyuki HIGASHIMURA, Takeshi ISHIYAMA