Patents by Inventor Masakatsu Daijyo

Masakatsu Daijyo 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: 4819157
    Abstract: An overcurrent protection circuit for an inverter device including three arms each composed of a pair of series connected electric gates, a junction therebetween being connected to a load and opposite ends being connected across a d.c. power source, and adapted to supply a three-phase a.c. power to the load by on-off controlling the electric gates sequentially according to on-off signals of the electric gates supplied from a control circuit. Majority logic circuitry is provided, and stress conditions in the electric gates which receive substantially a stress produced when the electric gates are turned off are detected in order to release these gates from a large stress exerted on the gates when an output short-circuit occurs. The majority logic circuitry control the sequence of turning off the electric gates so that the stress on the detected gate is reduced, to protect the gates from damage due to excess stress on the gates when the output short-circuit occurs.
    Type: Grant
    Filed: October 2, 1987
    Date of Patent: April 4, 1989
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kenji Hirose, Eiichi Sugishima, Masakatsu Daijyo