Patents by Inventor Takashi Masuhara

Takashi Masuhara 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: 20230308086
    Abstract: A drive circuit drives a power semiconductor element including a gate electrode, a first main electrode and a second main electrode. The drive circuit includes: a controller to control an opened/closed state of the power semiconductor element based on an externally received command; a short circuit determination circuitry to determine whether the power semiconductor element is in a short-circuited state in a turn-on operation of the power semiconductor element, and output a determination signal indicating a determination result; and a filter to receive the determination signal from the short circuit determination circuitry, generate a delay signal of the determination signal, and output the delay signal to the controller. A delay time of the filter is set to be longer than a length of a Miller period in the turn-on operation of the power semiconductor element.
    Type: Application
    Filed: October 28, 2020
    Publication date: September 28, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventor: Takashi MASUHARA
  • Patent number: 10917083
    Abstract: A drive circuit includes: a signal generation circuit; a comparator; a comparator; and a short circuit determination unit. The signal generation circuit is configured to generate, as an output signal, a differential amplification signal of a voltage detection signal indicating a gate voltage of a semiconductor element and a delay signal of the voltage detection signal. The comparator is configured to compare a value of the differential amplification signal with a first reference voltage value. The comparator is configured to compare a voltage value indicating a gate current with a second reference voltage value. The short circuit determination unit is configured to determine whether or not the semiconductor element is in a short-circuited state, based on a result of comparison by each of the comparators, and generate a determination signal indicating a determination result.
    Type: Grant
    Filed: June 13, 2017
    Date of Patent: February 9, 2021
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Takashi Masuhara, Takeshi Horiguchi
  • Patent number: 10790813
    Abstract: A drive circuit for a power semiconductor element according to the present disclosure includes: a control command unit that outputs a turn-on command for a power semiconductor element; a gate voltage detection unit that detects a gate voltage applied to a gate terminal after the control command unit outputs the turn-on command; a differentiator that subjects the gate voltage detected by the gate voltage detection unit to time differentiation; and a determination unit that determines, based on the gate voltage detected by the gate voltage detection unit and a differential value by the differentiator, whether the power semiconductor element is in a short-circuit state or not.
    Type: Grant
    Filed: May 17, 2018
    Date of Patent: September 29, 2020
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Yasushige Mukunoki, Takashi Masuhara, Takeshi Horiguchi
  • Publication number: 20200212906
    Abstract: A drive circuit for a power semiconductor element according to the present disclosure includes: a control command unit that outputs a turn-on command for a power semiconductor element; a gate voltage detection unit that detects a gate voltage applied to a gate terminal after the control command unit outputs the turn-on command; a differentiator that subjects the gate voltage detected by the gate voltage detection unit to time differentiation; and a determination unit that determines, based on the gate voltage detected by the gate voltage detection unit and a differential value by the differentiator, whether the power semiconductor element is in a short-circuit state or not.
    Type: Application
    Filed: May 17, 2018
    Publication date: July 2, 2020
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yasushige MUKUNOKI, Takashi MASUHARA, Takeshi HORIGUCHI
  • Patent number: 10637345
    Abstract: A semiconductor device includes a positive electrode-side semiconductor element, a negative electrode-side semiconductor element, a positive electrode plate, a negative electrode plate, an AC electrode plate, a positive electrode-side auxiliary electrode terminal, a negative electrode-side auxiliary electrode terminal, a positive electrode-side capacitor, and a negative electrode-side capacitor. The positive electrode plate is connected to a first positive electrode of the positive electrode-side semiconductor element. The negative electrode plate is connected to a second negative electrode of the negative electrode-side semiconductor element. The AC electrode plate is connected to a first negative electrode of the positive electrode-side semiconductor element and a second positive electrode of the negative electrode-side semiconductor element. The positive electrode-side capacitor is connected to the positive electrode plate and the positive electrode-side auxiliary electrode terminal.
    Type: Grant
    Filed: June 23, 2017
    Date of Patent: April 28, 2020
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takashi Masuhara, Takeshi Horiguchi, Mamoru Kamikura, Kodai Katagiri
  • Publication number: 20200127657
    Abstract: A drive circuit includes: a signal generation circuit; a comparator; a comparator; and a short circuit determination unit. The signal generation circuit is configured to generate, as an output signal, a differential amplification signal of a voltage detection signal indicating a gate voltage of a semiconductor element and a delay signal of the voltage detection signal. The comparator is configured to compare a value of the differential amplification signal with a first reference voltage value. The comparator is configured to compare a voltage value indicating a gate current with a second reference voltage value. The short circuit determination unit is configured to determine whether or not the semiconductor element is in a short-circuited state, based on a result of comparison by each of the comparators, and generate a determination signal indicating a determination result.
    Type: Application
    Filed: June 13, 2017
    Publication date: April 23, 2020
    Applicant: Mitsubishi Electric Corporation
    Inventors: Takashi MASUHARA, Takeshi HORIGUCHI
  • Publication number: 20200052573
    Abstract: A semiconductor device includes a positive electrode-side semiconductor element, a negative electrode-side semiconductor element, a positive electrode plate, a negative electrode plate, an AC electrode plate, a positive electrode-side auxiliary electrode terminal, a negative electrode-side auxiliary electrode terminal, a positive electrode-side capacitor, and a negative electrode-side capacitor. The positive electrode plate is connected to a first positive electrode of the positive electrode-side semiconductor element. The negative electrode plate is connected to a second negative electrode of the negative electrode-side semiconductor element. The AC electrode plate is connected to a first negative electrode of the positive electrode-side semiconductor element and a second positive electrode of the negative electrode-side semiconductor element. The positive electrode-side capacitor is connected to the positive electrode plate and the positive electrode-side auxiliary electrode terminal.
    Type: Application
    Filed: June 23, 2017
    Publication date: February 13, 2020
    Applicant: Mitsubishi Electric Corporation
    Inventors: Takashi MASUHARA, Takeshi HORIGUCHI, Mamoru KAMIKURA, Kodai KATAGIRI
  • Patent number: 4915438
    Abstract: A vehicular seating apparatus includes an assistant driver's seat mounted in the interior of a driver cabin of a vehicle and above a service hole on an engine deck raised at a central part of a floor located in the proximity of a driver's seat. The apparatus includes a transverse displacement mechanism for displacing the assistant driver's seat in the transverse direction and a transverse leap-up mechanism for upwardly turning the assistant driver's seat about one end of a seat cushion of the assistant driver's seat located at the side of the driver's seat. A seat frame is provided with a longitudinal slide mechanism for slidably displacing the assistant driver's seat in the longitudinal direction. The apparatus assures that a driver can walk by the side of the assistant driver's seat to reach the rear part of a driver cabin while maintaining good engine service performance. Further, the driver can enjoy excellent driving comfort by virtue of various operations for displacement.
    Type: Grant
    Filed: February 2, 1989
    Date of Patent: April 10, 1990
    Assignee: Mazda Motor Corporation
    Inventors: Teruo Hashimoto, Takashi Masuhara, Tetsuro Murakami, Yoshinori Murakami, Tetsuya Kameshima