Patents by Inventor Shuji Kazuma

Shuji Kazuma 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).

  • Synchronous rectification mode dc-to-dc converter power supply device
    Patent number: 7304459
    Abstract: A DC-to-DC converter power supply device includes drive circuits for generating different drive waveforms from a drive pulse of an oscillation control circuit portion; a first switching element driven by a drive circuit; a second switching element driven by a drive circuit; and a third switching element connected in parallel to a second diode of the second switching element and driven by the drive circuit.
    Type: Grant
    Filed: November 11, 2003
    Date of Patent: December 4, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Shuji Kazuma
  • Synchronous rectification mode dc-to-dc converter power supply device
    Publication number: 20060109697
    Abstract: A DC-to-DC converter power supply device includes drive circuits for generating different drive waveforms from a drive pulse of an oscillation control circuit portion; a first switching element driven by a drive circuit; a second switching element driven by a drive circuit; and a third switching element connected in parallel to a second diode of the second switching element and driven by the drive circuit.
    Type: Application
    Filed: November 11, 2003
    Publication date: May 25, 2006
    Inventor: Shuji Kazuma
  • Speed controlling circuit of dubbing recorder and dubbing equipment using the speed controlling circuit
    Patent number: 6167187
    Abstract: A speed control circuit for a dubbing recorder includes a demodulation circuit which receives a video signal for dubbing from a master VTR, a sync separation circuit to separate a sync signal from the output signal of the demodulation circuit, a detection circuit to detect the frequency of a portion of the video signal using the sync signal, and a system control circuit to determine the speed mode of the master VTR based on the output signal of the detection circuit.
    Type: Grant
    Filed: August 10, 1998
    Date of Patent: December 26, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shuji Kazuma, Kenji Masuda