Patents by Inventor Yohei MITSUI

Yohei MITSUI 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: 12081115
    Abstract: A semiconductor drive device includes a drive circuit that drives a semiconductor switching element, a passive element connected to a gate of the semiconductor switching element to prevent a gate current of the semiconductor switching element, a switching element connected in series to the passive element, a control circuit that controls the switching element, and a temperature detection circuit that detects a temperature of the semiconductor switching element. The control circuit controls the switching element such that when the temperature detected by the temperature detection circuit is high, the gate current is prevented more than when the temperature is low.
    Type: Grant
    Filed: March 24, 2020
    Date of Patent: September 3, 2024
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Yohei Mitsui, Yasutaka Imamura, Junichi Nakashima
  • Publication number: 20240235542
    Abstract: A semiconductor device is subjected to ON/OFF control by controlling a gate voltage according to a drive control signal (Ssw). In a turn-on operation for charging a gate in response to transition of drive control signal (Ssw) from a first level (0) to a second level (1), a drive signal (Sdr) is set to first level (0) to discharge the gate at a first time (t1) after end of a Miller period (200) of a gate voltage (Vg), thereby providing a voltage drop period (210) in which gate voltage (Vg) temporarily drops. At a second time (t2), drive signal (Sdr) is again set to second level (1) to start charging the gate.
    Type: Application
    Filed: May 25, 2021
    Publication date: July 11, 2024
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yasutaka IMAMURA, Yohei MITSUI, Yukihiko WADA, Takayoshi MIKI
  • Publication number: 20230261654
    Abstract: A semiconductor device includes a power switching element and a drive device to drive the power switching element. The drive device includes a voltage source, a switching element, a capacitor connected in parallel to the voltage source with the switching element being interposed, a switching element provided between the capacitor and a gate terminal of the power switching element, a first comparison device to output a result of comparison between a voltage of the capacitor and a reference value VQR, a second comparison device to output a result of comparison between a gate voltage of the power switching element and a reference value VR, and a short-circuit determination unit that makes determination as to a short circuit of the power switching element based on an output signal from the first comparison device and an output signal from the second comparison device.
    Type: Application
    Filed: September 7, 2020
    Publication date: August 17, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yohei MITSUI, Yasutaka IMAMURA, Takeshi HORIGUCHI, Yasushige MUKUNOKI
  • Publication number: 20230122671
    Abstract: A semiconductor drive device includes a drive circuit that drives a semiconductor switching element, a passive element connected to a gate of the semiconductor switching element to prevent a gate current of the semiconductor switching element, a switching element connected in series to the passive element, a control circuit that controls the switching element, and a temperature detection circuit that detects a temperature of the semiconductor switching element. The control circuit controls the switching element such that when the temperature detected by the temperature detection circuit is high, the gate current is prevented more than when the temperature is low.
    Type: Application
    Filed: March 24, 2020
    Publication date: April 20, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yohei MITSUI, Yasutaka IMAMURA, Junichi NAKASHIMA
  • Publication number: 20230047896
    Abstract: This temperature detection circuit includes: a temperature sensor having a resistance value that changes according to a change in temperature; an AC power supply that supplies AC power to the temperature sensor; a resonance circuit connected to the temperature sensor, the resonance circuit having an impedance that has an extreme value when AC power having a resonance frequency is supplied; and a voltage detection circuit that detects a voltage applied to any of a plurality of elements connected to the AC power supply. The resonance frequency in the resonance circuit and the frequency of the AC power are set to coincide with each other.
    Type: Application
    Filed: April 3, 2020
    Publication date: February 16, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yasutaka IMAMURA, Yohei MITSUI, Junichi NAKASHIMA
  • Patent number: 10342420
    Abstract: An endoscope accessory case includes: a case body made up of a bottom portion and an impermeable trunk portion, the case body including an opening portion provided in a top face, and a fluid introduction port configured to introduce a fluid; and an impermeable lid, the lid including a contact portion configured to come into contact with the case body, and a bubble lead-out edge located at a position apart from an inner circumference of the case body and configured to lead out bubbles separated from endoscope accessories when the endoscope accessories held in the case body are agitated by being pushed by the fluid, the lid being configured to detachably cover the opening portion.
    Type: Grant
    Filed: June 29, 2017
    Date of Patent: July 9, 2019
    Assignee: OLYMPUS CORPORATION
    Inventors: Yohei Mitsui, Shinichiro Kawachi, Hisato Kogure
  • Publication number: 20170296045
    Abstract: An endoscope accessory case includes: a case body made up of a bottom portion and an impermeable trunk portion, the case body including an opening portion provided in a top face, and a fluid introduction port configured to introduce a fluid; and an impermeable lid, the lid including a contact portion configured to come into contact with the case body, and a bubble lead-out edge located at a position apart from an inner circumference of the case body and configured to lead out bubbles separated from endoscope accessories when the endoscope accessories held in the case body are agitated by being pushed by the fluid, the lid being configured to detachably cover the opening portion.
    Type: Application
    Filed: June 29, 2017
    Publication date: October 19, 2017
    Applicant: OLYMPUS CORPORATION
    Inventors: Yohei MITSUI, Shinichiro KAWACHI, Hisato KOGURE