Patents by Inventor Takao Kishikawa

Takao Kishikawa 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: 6795324
    Abstract: A power converter is disclosed, in which the sum of the length of that portion of a control signal line which is in opposite relation to an area of a main circuit wiring where a main circuit current flows and a plurality of tabular conductors are in superposed relation with each other, the length of that portion of the control signal line which is in opposite relation to an area of the main circuit wiring where the main circuit current does not flow and the length of that portion of the control signal line which is located outside an end of the main circuit wiring, is substantially equal to the total wiring length of the signal control line.
    Type: Grant
    Filed: March 19, 2002
    Date of Patent: September 21, 2004
    Assignees: Hitachi, Ltd., Hitachi Building Systems Co., Ltd.
    Inventors: Kazuhisa Mori, Takashi Ikimi, Satoshi Fukuda, Takao Kishikawa, Tomoharu Sakoda
  • Publication number: 20030002311
    Abstract: A power converter is disclosed, in which the sum of the length of that portion of a control signal line which is in opposite relation to an area of a main circuit wiring where a main circuit current flows and a plurality of tabular conductors are in superposed relation with each other, the length of that portion of the control signal line which is in opposite relation to an area of the main circuit wiring where the main circuit current does not flow and the length of that portion of the control signal line which is located outside an end of the main circuit wiring, is substantially equal to the total wiring length of the signal control line.
    Type: Application
    Filed: March 19, 2002
    Publication date: January 2, 2003
    Inventors: Kazuhisa Mori, Takashi Ikimi, Satoshi Fukuda, Takao Kishikawa, Tomoharu Sakoda
  • Patent number: 6492790
    Abstract: A driving system for driving an AC motor, which is capable of promptly switching to an individual inverter operation mode, wherein a control instruction for each of a plurality of power converters is generated by summing outputs of a plurality of current compensation units connected in parallel, and each of the plurality of current compensation units makes compensation to reduce a deviation of a detected output current value of an associated power converter from a current instruction value to be outputted from the power converter to zero.
    Type: Grant
    Filed: February 26, 2001
    Date of Patent: December 10, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Toshifumi Yoshikawa, Naoto Ohnuma, Toshisuke Mine, Takao Kishikawa, Sadao Hokari
  • Patent number: 6490187
    Abstract: A semiconductor electric power conversion device includes a converter unit and an inverter unit, each having a group of parallel capacitors and multiple switching elements. Subdivided positive conductive connections associated with the converter unit and divided positive conductive connections associated with the inverter unit are formed at a positive side conductor connected to capacitors; while divided negative conductive connections associated with the converter unit and divided negative-polarity conductive connections associated with the inverter unit are formed at a negative polarity side conductor, connected to capacitors. The positive and negative polarity conductors have a multilayer structure with a dielectric plate interposed therebetween.
    Type: Grant
    Filed: September 6, 2001
    Date of Patent: December 3, 2002
    Assignees: Hitachi, Ltd., Hitachi Building Systems Co., Ltd.
    Inventors: Kazuhisa Mori, Asako Koyanagi, Satoshi Fukuda, Toshisuke Mine, Takao Kishikawa, Tomoharu Sakoda
  • Publication number: 20020034089
    Abstract: In a semiconductor electric power conversion device including a converter unit and an inverter unit each having a group of parallel-connected capacitors and multiple switching elements, subdivided positive-polarity conductive connection (connecting conductor) sections 21a1-21a3 associated with the converter unit and divided positive-polarity conductive connection (connecting conductor) sections 21b1-21b3 associated with the inverter unit are formed at a positive polarity side conductor 21 being connected to capacitors while divided negative-polarity conductive connection (connecting conductor) sections 22a1-22a3 associated with the converter unit and divided negative-polarity conductive connection (connecting conductor) sections 22b1-22b2 associated with the inverter unit are formed at a negative polarity side conductor 22 as connected to capacitors, wherein the positive polarity side conductor 21 and negative polarity side conductor 22 are formed to have a multilayer structure with a dielectric plate 20 inte
    Type: Application
    Filed: September 6, 2001
    Publication date: March 21, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Kazuhisa Mori, Asako Koyanagi, Satoshi Fukuda, Toshisuke Mine, Takao Kishikawa, Tomoharu Sakoda
  • Publication number: 20020005704
    Abstract: A driving system for driving an AC motor, which is capable of promptly switching to an individual inverter operation mode, wherein a control instruction for each of a plurality of power converters is generated by summing outputs of a plurality of current compensation units connected in parallel, and each of the plurality of current compensation units makes compensation to reduce a deviation of a detected output current value of an associated power converter from a current instruction value to be outputted from the power converter to zero.
    Type: Application
    Filed: February 26, 2001
    Publication date: January 17, 2002
    Inventors: Toshifumi Yoshikawa, Naoto Ohnuma, Toshisuke Mine, Takao Kishikawa, Sadao Hokari