Patents by Inventor Naoki Sakurai

Naoki Sakurai 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: 11971569
    Abstract: There is provided a light emitting device that can be used as a light guide plate and has an excellent antireflection function to extraneous light, and an optical body includes: a base material; a macro concave-convex structure that is formed on one surface of the base material and emits internally propagating light that is injected in an inside of the base material from a side surface of the base material, from another surface of the base material; and a micro concave-convex structure formed periodically to follow each of both surfaces of the base material and a surface of the macro concave-convex structure, and having an average period of concavity and convexity of less than or equal to a wavelength of visible light. The surface of the macro concave-convex structure has an inclined surface, and an arrangement of the micro concave-convex structure is a zigzag arrangement.
    Type: Grant
    Filed: March 23, 2017
    Date of Patent: April 30, 2024
    Assignee: DEXERIALS CORPORATION
    Inventors: Shunichi Kajiya, Kyoko Sakurai, Katsuhiro Doi, Kazuya Hayashibe, Naoki Hanashima, Naoto Kaneko
  • Publication number: 20240136318
    Abstract: A semiconductor device includes a semiconductor element having an Ni—V electrode and a conductor, the semiconductor element and the conductor being bonded via Sn-based lead-free solder. In the semiconductor device, an Sn—V compound layer and an (Ni, Cu)3Sn4 compound layer adjacent to the Sn—V compound are formed adjacent to an interface between the semiconductor element and the Sn-based lead-free solder. A manufacturing method for a semiconductor device according to the present invention includes: causing the Sn-based lead-free solder and the Ni—V electrode to react with each other to form an Sn—V layer and an (Ni, Cu)3Sn4 compound layer; and following formation of the Sn—V layer, leaving an unreacted layer of the Ni—V electrode, the unreacted layer having not reacted with the Sn-based lead-free solder, intact.
    Type: Application
    Filed: February 21, 2022
    Publication date: April 25, 2024
    Inventors: Osamu IKEDA, Naoki SAKURAI, Takayuki OSHIMA, Takuma HAKUTO
  • Patent number: 10888941
    Abstract: When a distance between an end portion of a brazing material and a downward extended line of a side surface of an insulating substrate is taken as “a”, and a distance between an end portion of a solder resist on the side of a solder and the downward extended line of the side surface of the insulating substrate is taken as “b”, the positional relationship a<b is satisfied. The position of the end portion of the solder is regulated by the solder resist, and the position of the end portion of the brazing material on the side of the side surface of the insulating substrate is closer to the side of the side surface of the insulating substrate than to the position of the end portion of the solder on the side of the side surface of the insulating substrate.
    Type: Grant
    Filed: October 24, 2018
    Date of Patent: January 12, 2021
    Assignee: HITACHI POWER SEMICONDUCTOR DEVICE, LTD.
    Inventors: Daichi Kawamura, Toru Masuda, Junpei Kusukawa, Naoki Sakurai
  • Patent number: 10804765
    Abstract: A highly reliable electromechanical integral motor is provided. In the electromechanical integral motor including an axial gap type motor and a power conversion control device, the power conversion control device is mounted on an end bracket portion of the motor. Additionally, a space is provided between the end bracket portion of the motor and the power conversion control device. Further, the end bracket portion of the motor and the power conversion control device are fixed by a plurality of fixing members, and at least one set of the plurality of fixing members is disposed to be spaced apart from each other.
    Type: Grant
    Filed: November 4, 2016
    Date of Patent: October 13, 2020
    Assignee: HITACHI, LTD.
    Inventors: Hisashi Tanie, Yoshitaka Iwaji, Yuji Enomoto, Hirooki Tokoi, Takayoshi Nakamura, Naoki Sakurai, Fusao Houjyou, Kohei Matsushita
  • Patent number: 10566876
    Abstract: To significantly improve a heat dissipation property of an axial gap rotary electric machine within a size necessary for configuring a motor. In an axial gap rotary electric machine comprising a stator and a rotor in an axial direction, the stator has a plurality of stator cores arranged in a circumferential direction and coils wound around the stator cores, and a heat pipe obtained by filling an inside of a metal hollow pipe with a refrigerant is arranged in a gap between adjacent coils formed in an outer diameter portion of the stator in a radial direction and a housing with a necessary insulation distance between the coils and the heat pipe. The heat pipe extends in a direction of a rotation axis and an opposite output side, and is in contact with a heat dissipating fin outside an end bracket on the opposite output side.
    Type: Grant
    Filed: February 25, 2016
    Date of Patent: February 18, 2020
    Assignee: Hitachi, Ltd.
    Inventors: Yuji Enomoto, Hirooki Tokoi, Naoki Sakurai, Hisashi Tanie, Kenta Deguchi
  • Patent number: 10318679
    Abstract: In a calculation method of calculating a switching wave form of an inverter by expressing a wave form obtained by measurement or simulation using a function formula, an intermediate terminal is provided between an upper terminal and a lower terminal of an inverter arm and a power supply of a voltage function formula is provided between the upper terminal and the intermediate terminal or the intermediate terminal and the lower terminal. Further, it may be configured such that a variation impact from peripheral circuits at time of switching is calculated and voltage correction calculation is performed to prevent the calculated switching wave form from changing due to the calculation of the variation impact.
    Type: Grant
    Filed: December 9, 2015
    Date of Patent: June 11, 2019
    Assignee: Hitachi, Ltd.
    Inventors: Kazutami Tago, Naoki Sakurai, Kinya Kobayashi
  • Publication number: 20190126374
    Abstract: When a distance between an end portion of a brazing material and a downward extended line of a side surface of an insulating substrate is taken as “a”, and a distance between an end portion of a solder resist on the side of a solder and the downward extended line of the side surface of the insulating substrate is taken as “b”, the positional relationship a<b is satisfied. The position of the end portion of the solder is regulated by the solder resist, and the position of the end portion of the brazing material on the side of the side surface of the insulating substrate is closer to the side of the side surface of the insulating substrate than to the position of the end portion of the solder on the side of the side surface of the insulating substrate.
    Type: Application
    Filed: October 24, 2018
    Publication date: May 2, 2019
    Inventors: Daichi KAWAMURA, Toru MASUDA, Junpei KUSUKAWA, Naoki SAKURAI
  • Publication number: 20190058374
    Abstract: To significantly improve a heat dissipation property of an axial gap rotary electric machine within a size necessary for configuring a motor. In an axial gap rotary electric machine comprising a stator and a rotor in an axial direction, the stator has a plurality of stator cores arranged in a circumferential direction and coils wound around the stator cores, and a heat pipe obtained by filling an inside of a metal hollow pipe with a refrigerant is arranged in a gap between adjacent coils formed in an outer diameter portion of the stator in a radial direction and a housing with a necessary insulation distance between the coils and the heat pipe. The heat pipe extends in a direction of a rotation axis and an opposite output side, and is in contact with a heat dissipating fin outside an end bracket on the opposite output side.
    Type: Application
    Filed: February 25, 2016
    Publication date: February 21, 2019
    Applicant: Hitachi .Ltd.
    Inventors: Yuji ENOMOTO, Hirooki TOKOI, Naoki SAKURAI, Hisashi TANIE, Kenta DEGUCHI
  • Publication number: 20180358863
    Abstract: An object of the present invention is to provide a highly reliable electromechanical integral motor. In an electromechanical integral motor including an axial gap type motor and a power conversion control device, the power conversion control device is mounted on an end bracket portion of the motor, a space is installed between the end bracket portion of the motor and the power conversion control device, the end bracket portion of the motor and the power conversion control device are fixed by a plurality of fixing members, and at least one set of the plurality of fixing members is disposed to be spaced apart from each other.
    Type: Application
    Filed: November 4, 2016
    Publication date: December 13, 2018
    Applicant: Hitachi, Ltd.
    Inventors: Hisashi TANIE, Yoshitaka IWAJI, Yuji ENOMOTO, Hirooki TOKOI, Takayoshi NAKAMURA, Naoki SAKURAI, Fusao HOUJYOU, Kohei MATSUSHITA
  • Patent number: 9594069
    Abstract: In a vibration information detection step, a probe is inserted into a food sample, and any one of the displacement, the velocity or the acceleration of a vibration occurring on the probe by the insertion is detected as vibration information (step S1). In a frequency band dividing step, the vibration information is divided by a band pass filter into individual pieces of vibration information in each of a plurality of frequency bands (step S2). In a food texture index calculation step, a food texture index value based on vibrational energy per unit time in each of the frequency bands is calculated using a computer from the vibration information in each of the frequency bands and the center frequency of the corresponding frequency band (step S3).
    Type: Grant
    Filed: August 31, 2011
    Date of Patent: March 14, 2017
    Assignee: HIROSHIMA UNIVERSITY
    Inventors: Naoki Sakurai, Shinichiro Iwatani, Hidemi Akimoto
  • Publication number: 20160171139
    Abstract: In a calculation method of calculating a switching wave form of an inverter by expressing a wave form obtained by measurement or simulation using a function formula, an intermediate terminal is provided between an upper terminal and a lower terminal of an inverter arm and a power supply of a voltage function formula is provided between the upper terminal and the intermediate terminal or the intermediate terminal and the lower terminal. Further, it may be configured such that a variation impact from peripheral circuits at time of switching is calculated and voltage correction calculation is performed to prevent the calculated switching wave form from changing due to the calculation of the variation impact.
    Type: Application
    Filed: December 9, 2015
    Publication date: June 16, 2016
    Inventors: Kazutami TAGO, Naoki SAKURAI, Kinya KOBAYASHI
  • Publication number: 20130228016
    Abstract: In a vibration information detection step, a probe is inserted into a food sample, and any one of the displacement, the velocity or the acceleration of a vibration occurring on the probe by the insertion is detected as vibration information (step S1). In a frequency band dividing step, the vibration information is divided by a band pass filter into individual pieces of vibration information in each of a plurality of frequency bands (step S2). In a food texture index calculation step, a food texture index value based on vibrational energy per unit time in each of the frequency bands is calculated using a computer from the vibration information in each of the frequency bands and the center frequency of the corresponding frequency band (step S3).
    Type: Application
    Filed: August 31, 2011
    Publication date: September 5, 2013
    Applicant: HIROSHIMA UNIVERSITY
    Inventors: Naoki Sakurai, Shinichiro Iwatani, Hidemi Akimoto
  • Patent number: 8399466
    Abstract: A composition for regenerative treatment of cartilage disease, which comprises a PDE4 inhibitor as an active ingredient, specifically a composition comprising a PDE4 inhibitor and a biocompatible and biodegradable polymer is provided, which composition, when formulated into a form suited to administer locally to affected cartilage region, such as microsphere preparation, can provide a pharmaceutical composition showing an excellent effect in regenerative treatment of cartilage.
    Type: Grant
    Filed: May 18, 2010
    Date of Patent: March 19, 2013
    Assignee: Mitsubishi Tanabe Pharma Corporation
    Inventors: Masaharu Takigawa, Naoki Sakurai, Toshiki Takagi, Noriyuki Yanaka, Yuji Horikiri, Takashi Tamura
  • Patent number: 8299836
    Abstract: In a level shift circuit, when a power-source voltage variation dV/dt of a high voltage side occurs and influences on a logic level of a circuit, the passing through of a malfunction signal is masked and prevented in the first and second logic circuits, by a signal from a time-constant generation circuit or a portion where a power voltage variation occurs in advance, by utilizing the fact that this variation occurs both at a set side and a reset side. When the power source voltage variation dV/dt is generated at a high voltage side, sufficient allowance in the timing of this masking prevents an erroneous signal from being transmitted to a flip-flop, and a control signal is transmitted from a low voltage side circuit not giving malfunction to a high voltage side circuit, even when there is a production variation in each element in semiconductor processes.
    Type: Grant
    Filed: February 17, 2011
    Date of Patent: October 30, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Naoki Sakurai, Junichi Sakano, Seigoh Yukutake
  • Patent number: 8252794
    Abstract: A composition for regenerative treatment of cartilage disease, which comprises a PDE4 inhibitor as an active ingredient, specifically a composition comprising a PDE4 inhibitor and a biocompatible and biodegradable polymer is provided, which composition, when formulated into a form suited to administer locally to affected cartilage region, such as microsphere preparation, can provide a pharmaceutical composition showing an excellent effect in regenerative treatment of cartilage.
    Type: Grant
    Filed: February 16, 2007
    Date of Patent: August 28, 2012
    Assignee: Mitsubishi Tanabe Pharma Corporation
    Inventors: Masaharu Takigawa, Naoki Sakurai, Toshiki Takagi, Noriyuki Yanaka, Yuji Horikiri, Takashi Tamura
  • Publication number: 20120153719
    Abstract: A semiconductor element control device that controls a semiconductor element that performs switching operation for converting DC power into AC power, or AC power into DC power, includes: a drive unit that outputs a drive signal for controlling the switching operation of the semiconductor element to a terminal of the semiconductor element; a short-circuit detection unit that detects short-circuit of the semiconductor element on the basis of the voltage at the terminal, and outputs a short-circuit detection signal; and a drive interruption unit that interrupts current flowing in the semiconductor element on the basis of the short-circuit detection signal output from the short-circuit detection unit.
    Type: Application
    Filed: July 22, 2010
    Publication date: June 21, 2012
    Applicant: Hitachi Automotive Systems, Ltd.
    Inventors: Masamitsu Inaba, Naoki Sakurai
  • Publication number: 20110227626
    Abstract: In a level shift circuit, when a power-source voltage variation dV/dt of a high voltage side occurs and influences on a logic level of a circuit, the passing through of a malfunction signal is masked and prevented in the first and second logic circuits, by a signal from a time-constant generation circuit or a portion where a power voltage variation occurs in advance, by utilizing the fact that this variation occurs both at a set side and a reset side. When the power source voltage variation dV/dt is generated at a high voltage side, sufficient allowance in the timing of this masking prevents an erroneous signal from being transmitted to a flip-flop, and a control signal is transmitted from a low voltage side circuit not giving malfunction to a high voltage side circuit, even when there is a production variation in each element in semiconductor processes.
    Type: Application
    Filed: February 17, 2011
    Publication date: September 22, 2011
    Inventors: Naoki SAKURAI, Junichi Sakano, Seigoh Yukutake
  • Patent number: 7973405
    Abstract: An integrated circuit for driving a semiconductor device, which is adaptable for demands, such as a higher output (larger current), a higher voltage, and a smaller loss, and has a small size, is produced at a low cost, and has high reliability. A power converter including such an integrated circuit is also provided. Circuit elements constituting a drive section of an upper arm drive circuit 212, a level shift circuit 20 including a current sensing circuit 210, a drive section of a lower arm drive circuit 222, and a drive signal processing circuit 224 are integrated and built in one high withstand voltage IC chip 200. Circuit elements constituting a final output stage buffer section 213 of the upper arm drive circuit 212 are built in a vertical p-channel MOS-FET chip 213p and a vertical n-channel MOS-FET chip 213n.
    Type: Grant
    Filed: May 20, 2010
    Date of Patent: July 5, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Yoshimasa Takahashi, Naoki Sakurai, Masashi Yura, Masahiro Iwamura, Mutsuhiro Mori
  • Patent number: 7957167
    Abstract: A high-reliability IGBT drive device in which the high- and low-voltage side IGBTs are complementarily ON/OFF controlled before and after dead time. A reset pulse that turns OFF the high-voltage side IGBT is generated during the dead time as described in the following example. The reset pulse is generated immediately before an ON instruction for the low-voltage side IGBT, so that a period that begins immediately before the ON instruction for the low-voltage side IGBT and overlaps with the ON instruction, continuously during the dead time, continuously during dead time immediately before the low-voltage side IGBT turns ON, or in such a manner as to invalidate the ON instruction for the low-voltage side IGBT when an ON state of the high-voltage side IGBT is observed.
    Type: Grant
    Filed: May 24, 2007
    Date of Patent: June 7, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Koji Yamaguchi, Naoki Sakurai
  • Patent number: 7851866
    Abstract: An object of the present invention is to provide an electric power converter including means for accurately detecting a principal current of IGBT. An electric power conversion device according to the present invention includes principal current estimation means for estimating a principal current by using: an output of temperature measuring means whose diode is disposed in the same semiconductor substrate as an IGBT including an emitter having flowing therethrough the principal current and a sense emitter having flowing therethrough a sense current proportional to the principal current; the sense current; and the information, preliminarily stored in memory means, on the relationship among the semiconductor substrate temperature, the principal current and the sense currant.
    Type: Grant
    Filed: January 25, 2006
    Date of Patent: December 14, 2010
    Assignee: Hitachi, Ltd.
    Inventors: Naoki Sakurai, Mutsuhiro Mori