Patents by Inventor Yasushi Nakayama

Yasushi Nakayama 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: 9281680
    Abstract: A power switching circuit includes a power semiconductor element that includes a main switching element connected in parallel with a main body diode and a sense switching element connected in parallel with a sense body diode; a reverse overcurrent detection circuit that detects an overcurrent flowing in the reverse direction out of currents flowing through a parallel-connection body of the sense switching element and the sense body diode; and a control circuit that drives the gate of the power semiconductor element; wherein when the reverse overcurrent detection circuit detects a reverse overcurrent, the control circuit controls the main switching element and the sense switching element to turn on.
    Type: Grant
    Filed: February 8, 2013
    Date of Patent: March 8, 2016
    Assignee: Mitsubishi Electric Corporation
    Inventor: Yasushi Nakayama
  • Patent number: 9209677
    Abstract: When an overcurrent detection section detects an overcurrent, a control circuit performs ON-OFF control for switching devices each switchable between a forward direction and a reverse direction, in a mode in which a current having flowed is reduced, such that when the mode is a mode in which a current is passed through any of diodes, a switching device connected in parallel with the current-passed diode is turned ON. Thus, even when an overcurrent occurs, the current flowing in the diode connected in parallel with the switching device is reduced, and the diode is protected from being deteriorated or broken by the overcurrent.
    Type: Grant
    Filed: June 28, 2011
    Date of Patent: December 8, 2015
    Assignee: Mitsubishi Electric Corporation
    Inventors: Yasushi Nakayama, Satoshi Azuma
  • Patent number: 9181359
    Abstract: A method of production of ethylene-based polymer particles includes the steps of: homopolymerizing ethylene or copolymerizing ethylene and a linear or branched ?-olefin having 3 to 20 carbon atoms in the presence of an olefin polymerization catalyst including: (A) fine particles having an average particle diameter greater than or equal to 1 nm and less than or equal to 300 nm obtained at least by the following two steps: (Step 1) causing contact between a metal halide and an alcohol in a hydrocarbon solvent; (Step 2) causing contact between a component obtained by (Step 1) and an organoaluminum compound and/or an organoaluminumoxy compound; and (B) a transition metal compound represented in General Formula (I) or (II), and (E) an intrinsic viscosity [?] of the ethylene-based polymer particles, measured in decalin at 135° C., is from 5 to 50 dL/g.
    Type: Grant
    Filed: July 15, 2011
    Date of Patent: November 10, 2015
    Assignee: MITSUI CHEMICALS, INC.
    Inventors: Fumiaki Nishino, Takeshi Karino, Takayuki Onogi, Susumu Murata, Naoto Matsukawa, Yasunori Yoshida, Yasushi Nakayama
  • Patent number: 9129885
    Abstract: A power semiconductor module in which temperature rise of switching elements made of a Si semiconductor can be suppressed low and efficiency of cooling the module can be enhanced. To that end, the power semiconductor module includes switching elements made of the Si semiconductor and diodes made of a wide-bandgap semiconductor, the diodes are arranged in the middle region of the power semiconductor module, and the switching elements are arranged in both sides or in the periphery of the middle region of the power semiconductor module.
    Type: Grant
    Filed: January 12, 2011
    Date of Patent: September 8, 2015
    Assignee: Mitsubishi Electric Corporation
    Inventors: Yasushi Nakayama, Takayoshi Miki, Takeshi Oi, Kazuhiro Tada, Shiori Idaka, Shigeru Hasegawa, Takeshi Tanaka
  • Patent number: 8994165
    Abstract: A power semiconductor device includes power semiconductor elements joined to wiring patterns of a circuit substrate, cylindrical external terminal communication sections, and wiring means for forming electrical connection between, for example, the power semiconductor elements and the cylindrical external terminal communication sections. The power semiconductor elements, the cylindrical external terminal communication sections, and the wiring means are sealed with transfer molding resin. The cylindrical external terminal communication sections are arranged on the wiring patterns so as to be substantially perpendicular to the wiring patterns, such that external terminals are insertable and connectable to the cylindrical external terminal communication sections, and such that a plurality of cylindrical external terminal communication sections among the cylindrical external terminal communication sections are arranged two-dimensionally on each of wiring patterns that act as main circuits.
    Type: Grant
    Filed: July 16, 2009
    Date of Patent: March 31, 2015
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takeshi Oi, Seiji Oka, Yoshiko Obiraki, Osamu Usui, Yasushi Nakayama
  • Patent number: 8952520
    Abstract: A power semiconductor device with improved productivity, reduced size and reduction of amounting area therefore is provided. In the provided power semiconductor device, an external terminal does not limit an increase in current. The power semiconductor device is sealed with transfer molding resin. In the power semiconductor device, a cylindrical external terminal communication section is arranged on a wiring pattern so as to be substantially perpendicular to the wiring pattern. An external terminal can be inserted and connected to the cylindrical external terminal communication section. The cylindrical external terminal communication section allows the inserted external terminal to be electrically connected to the wiring pattern. A taper is formed at, at least, one end of the cylindrical external terminal communication section, which one end is joined to the wiring pattern.
    Type: Grant
    Filed: July 16, 2009
    Date of Patent: February 10, 2015
    Assignee: Mitsubishi Electric Corporation
    Inventors: Yoshiko Obiraki, Seiji Oka, Osamu Usui, Yasushi Nakayama, Takeshi Oi
  • Publication number: 20150023081
    Abstract: A power semiconductor module capable of reducing variation of inductance between upper/lower arms and reducing variation of current caused by the variation of inductance. The power semiconductor module includes circuit blocks (upper/lower arms) each of which is configured by connecting self-arc-extinguishing type semiconductor elements in series; a positive electrode terminal, a negative electrode terminal, and an AC terminal that are connected to each of the circuit blocks; and wiring patterns that connect the self-arc-extinguishing type semiconductor elements of the circuit blocks to the positive electrode terminal, the negative electrode terminal, and the AC terminal, wherein the circuit block is plural in number; the positive electrode terminal, the negative electrode terminal, and the AC terminal are each disposed to be plural in number corresponding to the circuit blocks; and the positive electrode terminals and the negative electrode terminals are closely disposed.
    Type: Application
    Filed: January 16, 2013
    Publication date: January 22, 2015
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yoshiko Obiraki, Yasushi Nakayama, Yuji Miyazaki, Hiroshi Nakatake
  • Publication number: 20140321012
    Abstract: A power switching circuit includes a power semiconductor element that includes a main switching element connected in parallel with a main body diode and a sense switching element connected in parallel with a sense body diode; a reverse overcurrent detection circuit that detects an overcurrent flowing in the reverse direction out of currents flowing through a parallel-connection body of the sense switching element and the sense body diode; and a control circuit that drives the gate of the power semiconductor element; wherein when the reverse overcurrent detection circuit detects a reverse overcurrent, the control circuit controls the main switching element and the sense switching element to turn on.
    Type: Application
    Filed: February 8, 2013
    Publication date: October 30, 2014
    Applicant: Mitsubishi Electric Corporation
    Inventor: Yasushi Nakayama
  • Publication number: 20140138707
    Abstract: A power semiconductor module is provided which is capable of keeping low the degrees of increases in temperatures of wide bandgap semiconductor elements, reducing the degree of increase in chip's total surface area of the wide bandgap semiconductor elements, and being fabricated at low costs, when Si semiconductor elements and the wide bandgap semiconductor elements are placed within one and the same power semiconductor module. The Si semiconductor elements are placed in a central region of the power semiconductor module, and the wide bandgap semiconductor elements are placed on opposite sides relative to the central region or in edge regions surrounding the central region.
    Type: Application
    Filed: July 5, 2012
    Publication date: May 22, 2014
    Applicant: Mitsubishi Electric Corporation
    Inventors: Takayoshi Miki, Yasushi Nakayama, Takeshi Oi, Kazuhiro Tada, Shiori Idaka, Shigeru Hasegawa, Tomohiro Kobayashi, Yukio Nakashima
  • Publication number: 20130223114
    Abstract: When an overcurrent detection section detects an overcurrent, a control circuit performs ON-OFF control for switching devices each switchable between a forward direction and a reverse direction, in a mode in which a current having flowed is reduced, such that when the mode is a mode in which a current is passed through any of diodes, a switching device connected in parallel with the current-passed diode is turned ON. Thus, even when an overcurrent occurs, the current flowing in the diode connected in parallel with the switching device is reduced, and the diode is protected from being deteriorated or broken by the overcurrent.
    Type: Application
    Filed: June 28, 2011
    Publication date: August 29, 2013
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yasushi Nakayama, Satoshi Azuma
  • Patent number: 8519751
    Abstract: A gate drive circuit capable of turning on a semiconductor switching element at high speed, which includes: a buffer circuit including a turn-on-drive switching element and a turn-off-drive switching element that are complementarily turned on and off, for driving the semiconductor switching element; a first DC voltage supply including a positive electrode connected to the source or emitter of the turn-on-drive switching element and a negative electrode connected to a reference potential; and a second DC voltage supply including a positive electrode connected to the source or emitter of the turn-off-drive switching element and a negative electrode connected to the reference potential.
    Type: Grant
    Filed: September 2, 2010
    Date of Patent: August 27, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventors: Tatsuya Kitamura, Hiroshi Nakatake, Yasushi Nakayama
  • Publication number: 20130209805
    Abstract: A method of production of ethylene-based polymer particles includes the steps of: homopolymerizing ethylene or copolymerizing ethylene and a linear or branched ?-olefin having 3 to 20 carbon atoms in the presence of an olefin polymerization catalyst including: (A) fine particles having an average particle diameter greater than or equal to 1 nm and less than or equal to 300 nm obtained at least by the following two steps: (Step 1) causing contact between a metal halide and an alcohol in a hydrocarbon solvent; (Step 2) causing contact between a component obtained by (Step 1) and an organoaluminum compound and/or an organoaluminumoxy compound; and (B) a transition metal compound represented in General Formula (I) or (II), and (E) an intrinsic viscosity [?] of the ethylene-based polymer particles, measured in decalin at 135° C., is from 5 to 50 dL/g.
    Type: Application
    Filed: July 15, 2011
    Publication date: August 15, 2013
    Applicant: MITSUI CHEMICALS, INC
    Inventors: Fumiaki Nishino, Takeshi Karino, Takayuki Onogi, Susumu Murata, Naoto Matsukawa, Yasunori Yoshida, Yasushi Nakayama
  • Patent number: 8349451
    Abstract: To provide capsular fine particles comprising an olefinic polymer which have a uniform particle size distribution and a uniform particle size, and which are spherical and free from the coagulation between particles. Capsular fine particles comprising the olefinic polymer, of which the ratio (L/M) of the outer diameter (L) to the inner diameter (M) is 1.1 to 6.0, and the average diameter is 0.6 to 40 ?m.
    Type: Grant
    Filed: April 7, 2006
    Date of Patent: January 8, 2013
    Assignee: Mitsui Chemicals, Inc.
    Inventors: Yasushi Nakayama, Naoto Matsukawa, Junji Saito, Susumu Murata, Makoto Mitani, Terunori Fujita
  • Publication number: 20120286292
    Abstract: A power semiconductor module in which temperature rise of switching elements made of a Si semiconductor can be suppressed low and efficiency of cooling the module can be enhanced. To that end, the power semiconductor module includes switching elements made of the Si semiconductor and diodes made of a wide-bandgap semiconductor, the diodes are arranged in the middle region of the power semiconductor module, and the switching elements are arranged in both sides or in the periphery of the middle region of the power semiconductor module.
    Type: Application
    Filed: January 12, 2011
    Publication date: November 15, 2012
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Yasushi Nakayama, Takayoshi Miki, Takeshi Oi, Kazuhiro Tada, Shiori Idaka, Shigeru Hasegawa, Takeshi Tanaka
  • Patent number: 8299603
    Abstract: A power semiconductor device in which transfer molding resin seals: a metallic circuit substrate; a power semiconductor element joined to a wiring pattern; and a side surface of a cylindrical external terminal communication section provided on the wiring pattern and to which an external terminal can be inserted and connected. The cylindrical external terminal communication section is substantially perpendicular to a surface on which the wiring pattern is formed. An outer surface of a metal plate of the metallic circuit substrate and a top portion of the cylindrical external terminal communication section are exposed from the transfer molding resin. The transfer molding resin is not present within the cylindrical external terminal communication section.
    Type: Grant
    Filed: January 18, 2008
    Date of Patent: October 30, 2012
    Assignee: Mitsubishi Electric Corporation
    Inventors: Seiji Oka, Osamu Usui, Yasushi Nakayama, Yoshiko Obiraki, Takeshi Oi
  • Publication number: 20120256574
    Abstract: A power semiconductor module applied to a power converting apparatus for a railway car includes an element pair formed by connecting an IGBT and an SiC-FWD in anti-parallel to each other and an element pair formed by connecting an Si-IGBT and an SiC-FWD in anti-parallel to each other. The element pair and the element pair are housed in one module and configured as a 2-in-1 module in a manner that the first element pair operates as a positive side arm of the power converting apparatus and the second element pair operates as a negative side arm of the power converting apparatus. The element pairs are formed such that a ratio of an occupied area of SiC-FWD chips to an occupied area of IGBT chips in the element pairs is equal to or higher than 15% and lower than 45%.
    Type: Application
    Filed: January 18, 2010
    Publication date: October 11, 2012
    Applicant: Mitsubishi Electric Corporation
    Inventors: Takeshi Tanaka, Yasushi Nakayama
  • Patent number: 8258361
    Abstract: The invention provides transition metal complex compounds, high-activity olefin oligomerization catalysts containing the compounds, and olefin oligomerization processes using the catalysts. A transition metal complex compound [A] according to the invention is represented by Formula (I) or Formula (I?) below. An olefin oligomerization catalyst includes the transition metal complex compound [A]. In an olefin oligomerization process of the invention, an olefin is oligomerized in the presence of the catalyst.
    Type: Grant
    Filed: June 27, 2008
    Date of Patent: September 4, 2012
    Assignee: Mitsui Chemicals, Inc.
    Inventors: Yasuhiko Suzuki, Shinsuke Kinoshita, Atsushi Shibahara, Naritoshi Yoshimura, Isao Hara, Tetsuya Hamada, Kazumori Kawamura, Kou Tsurugi, Yasunori Saito, Seiichi Ishii, Yasushi Nakayama, Naoto Matsukawa, Susumu Murata
  • Patent number: 8253236
    Abstract: A power semiconductor device includes power semiconductor elements joined to wiring patterns of a circuit substrate, cylindrical external terminal communication sections, and wiring means for forming electrical connection between, for example, the power semiconductor elements and the cylindrical external terminal communication sections. The power semiconductor elements, the cylindrical external terminal communication sections, and the wiring means are sealed with transfer molding resin. The cylindrical external terminal communication sections are arranged on the wiring patterns so as to be substantially perpendicular to the wiring patterns, such that external terminals are insertable and connectable to the cylindrical external terminal communication sections, and such that a plurality of cylindrical external terminal communication sections among the cylindrical external terminal communication sections are arranged two-dimensionally on each of wiring patterns that act as main circuits.
    Type: Grant
    Filed: April 14, 2011
    Date of Patent: August 28, 2012
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takeshi Oi, Seiji Oka, Yoshiko Obiraki, Osamu Usui, Yasushi Nakayama
  • Publication number: 20120153998
    Abstract: A gate drive circuit capable of turning on a semiconductor switching element at high speed, which includes: a buffer circuit including a turn-on-drive switching element and a turn-off-drive switching element that are complementarily turned on and off, for driving the semiconductor switching element; a first DC voltage supply including a positive electrode connected to the source or emitter of the turn-on-drive switching element and a negative electrode connected to a reference potential; and a second DC voltage supply including a positive electrode connected to the source or emitter of the turn-off-drive switching element and a negative electrode connected to the reference potential.
    Type: Application
    Filed: September 2, 2010
    Publication date: June 21, 2012
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Tatsuya Kitamura, Hiroshi Nakatake, Yasushi Nakayama
  • Patent number: 8107241
    Abstract: In a conventional cooling device, a heat pipe or a circulation-type liquid cooler provided with a pump is used and therefore, a large space is needed for the cooling device. There is provided a cooling device which includes a plurality of cooling modules having cooling units for cooling heat-generating elements by coolant and radiation units for radiating heat from the coolant heated in the cooling units, the plurality of cooling modules being bubble-pump-type ones in which the coolant is circulated between the radiation units and the cooling units by the coolant being boiled in the cooling units, the radiation units being arranged side by side, and a cooling fan for generating wind blowing the radiation units.
    Type: Grant
    Filed: March 31, 2006
    Date of Patent: January 31, 2012
    Assignee: Mitsubishi Electric Corporation
    Inventors: Tetsuya Takahashi, Kazuyoshi Toya, Akihiro Murahashi, Yasushi Nakayama, Shigetoshi Ipposhi, Kenichi Hayashi