Patents by Inventor Yuji Sayama

Yuji Sayama 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 for LED illumination
    Patent number: 9125268
    Abstract: An LED illumination system includes: a load including an LED lamp; and a power supply device, the LED lamp configured to be physically mounted on and demounted from the power supply device, the power supply device comprising: a current feedback control unit; a first voltage comparison unit configured to determine whether the load is in a mounted state; a voltage feedback control unit configured to decrease the voltage of the power supply device to a safe voltage when demounting, and to increase the voltage of the power supply device to perform the constant current control when mounting; and a semiconductor switch element connected in series between the load and the detection resistor, wherein the mounted and demounted states of the load is detected by a voltage of a main electrode of a high potential side of the semiconductor switch element.
    Type: Grant
    Filed: June 18, 2013
    Date of Patent: September 1, 2015
    Assignee: Sanken Electric Co., LTD.
    Inventors: Toshihiro Nakano, Kengo Kimura, Takayuki Yamashita, Yuji Sayama, Hiroaki Kiuchi
  • Power Supply for LED Illumination
    Publication number: 20130334968
    Abstract: An LED illumination system includes: a load including an LED lamp; and a power supply device, the LED lamp configured to be physically mounted on and demounted from the power supply device, the power supply device comprising: a current feedback control unit; a first voltage comparison unit configured to determine whether the load is in a mounted state; a voltage feedback control unit configured to decrease the voltage of the power supply device to a safe voltage when demounting, and to increase the voltage of the power supply device to perform the constant current control when mounting; and a semiconductor switch element connected in series between the load and the detection resistor, wherein the mounted and demounted states of the load is detected by a voltage of a main electrode of a high potential side of the semiconductor switch element.
    Type: Application
    Filed: June 18, 2013
    Publication date: December 19, 2013
    Inventors: Toshihiro Nakano, Kengo Kimura, Takayuki Yamashita, Yuji Sayama, Hiroaki Kiuchi