Patents by Inventor Tsutcmu Ohmae

Tsutcmu Ohmae 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).

  • Control apparatus for controlling transistor chopper for use in current supply for electric motor
    Patent number: 4291259
    Abstract: A control apparatus for controlling the supply of current for an electric motor, having a transistor chopper circuit which includes a plurality of power transistors connected in parallel, and a duty controlling oscillator circuit for controlling the ON-OFF operation of the transistor chopper circuit, by which the duty factor of current supplied for the motor through the transistor chopper circuit is controlled depending on a command signal, and wherein the operation of the duty controlling oscillator circuit is controlled depending on the amplitude of current flowing through one of the plurality of power transistors of the transistor chopper circuit.
    Type: Grant
    Filed: December 10, 1979
    Date of Patent: September 22, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Katsuji Marumoto, Tsutcmu Ohmae