Patents by Inventor Tetsuhiro Doi

Tetsuhiro Doi 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).

  • Power supply device and construction machine
    Patent number: 8125105
    Abstract: A power supply device comprises a bidirectional voltage converter unit that performs voltage stepping up or voltage stepping down between a first terminal and a second terminal; a first switching unit that applies a DC voltage obtained from the first electric power supply source to the first terminal; a second switching unit that applies a DC voltage obtained from the second electric power supply source to the first terminal; a third switching unit that applies a DC voltage obtained from the first electric power supply source to the second terminal; an output unit that outputs a predetermined DC voltage from the second terminal; and a switching control unit that controls switching of the first switching unit, the second switching unit and the third switching unit.
    Type: Grant
    Filed: October 21, 2009
    Date of Patent: February 28, 2012
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Toshihiko Ishida, Toshihiro Kimura, Tetsuhiro Doi
  • Power Supply Device and Construction Machine
    Publication number: 20100096921
    Abstract: A power supply device comprises a bidirectional voltage converter unit that performs voltage stepping up or voltage stepping down between a first terminal and a second terminal; a first switching unit that applies a DC voltage obtained from the first electric power supply source to the first terminal; a second switching unit that applies a DC voltage obtained from the second electric power supply source to the first terminal; a third switching unit that applies a DC voltage obtained from the first electric power supply source to the second terminal; an output unit that outputs a predetermined DC voltage from the second terminal; and a switching control unit that controls switching of the first switching unit, the second switching unit and the third switching unit.
    Type: Application
    Filed: October 21, 2009
    Publication date: April 22, 2010
    Applicant: HITACHI CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Toshihiko Ishida, Toshihiro Kimura, Tetsuhiro Doi