Patents by Inventor Takeaki Ogawa

Takeaki Ogawa 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).

  • Drive system and AC conversion device
    Patent number: 7315464
    Abstract: A drive system with small power loss in power conversion is provided. The drive system has an AC conversion device for converting commercial AC power from a commercial AC power supply and a DC conversion device. An AC power supply path for supplying power to discharge tubes, and a DC power supply path for supplying power to an image processing circuit or the like, are provided independently. The AC conversion device converts commercial AC power into converted AC power and gives the converted AC power to an AC drive device directly. Consequently, it is possible to reduce conversion steps for generating converted AC power and to reduce power loss that occurs in a conversion process. In particular, when power consumption of the discharge tubes is large, it is possible to reduce power loss in an entire liquid crystal display apparatus effectively by providing the AC conversion device.
    Type: Grant
    Filed: September 30, 2004
    Date of Patent: January 1, 2008
    Assignees: Sharp Kabushiki Kaisha, Sharp Niigata Electronics Corporation
    Inventors: Shinichi Sawada, Takeaki Ogawa, Naoki Tanaka
  • Drive system and AC conversion device
    Publication number: 20050105305
    Abstract: A drive system with small power loss in power conversion is provided. The drive system has an AC conversion device for converting commercial AC power from a commercial AC power supply and a DC conversion device. An AC power supply path for supplying power to discharge tubes, and a DC power supply path for supplying power to an image processing circuit or the like, are provided independently. The AC conversion device converts commercial AC power into converted AC power and gives the converted AC power to an AC drive device directly. Consequently, it is possible to reduce conversion steps for generating converted AC power and to reduce power loss that occurs in a conversion process. In particular, when power consumption of the discharge tubes is large, it is possible to reduce power loss in an entire liquid crystal display apparatus effectively by providing the AC conversion device.
    Type: Application
    Filed: September 30, 2004
    Publication date: May 19, 2005
    Applicants: Sharp Kabushiki Kaisha, Sharp Niigata Electronics Corporation
    Inventors: Shinichi Sawada, Takeaki Ogawa, Naoki Tanaka