Patents by Inventor Hirotsugu Tsutsui

Hirotsugu Tsutsui 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: 20200350756
    Abstract: An impulse voltage generation device comprises: a high voltage generator to generate high DC voltage; a capacitor that is disposed in parallel to the high voltage generator and can be charged to a high voltage state; a power semiconductor switch that is placed at an output side of the high voltage generator and in series to the high voltage generator and is designed to shut off or allow electricity output from the high voltage generator; a function generator to output changes over time of impulse voltage to be applied to the test target; a current detector to detect output current; and an overcurrent protection circuit that is configured to conduct analog-to-digital conversion at sampling intervals sufficiently shorter than the application intervals when receiving a current signal from the current detector, monitors values of the output current, and to block output from the function generator to the power semiconductor switch if it is determined that there is an abnormality.
    Type: Application
    Filed: July 17, 2020
    Publication date: November 5, 2020
    Applicant: Toshiba Mitsubishi-Electric Industrial Systems Corporation
    Inventors: Jintong SUN, Tetsuo YOSHIMITSU, Hirotsugu TSUTSUI, Kiyoshi UMEZU
  • Patent number: 6329734
    Abstract: A permanent magnet-reluctance type rotating machine includes an annular stator having armature windings arranged on an inner periphery of the stator, a rotor rotatably arranged inside the stator and a plurality of permanent magnets disposed in a rotor core. One permanent magnet defining each pole is divided into two magnet pieces in a direction parallel to the magnetizing direction of the permanent magnets. Owing to the division of the magnet, the mass of each permanent magnet becomes small in comparison with that of the conventional machine, so that the centrifugal force applied on the magnet holes can be reduced. Consequently, the stress generating in the rotor core is decreased to allow the rotating machine to rotate at a higher speed.
    Type: Grant
    Filed: February 22, 2000
    Date of Patent: December 11, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Norio Takahashi, Kazuto Sakai, Yutaka Hashiba, Masanori Arata, Hirotsugu Tsutsui