Patents by Inventor Sunji Kurokawa

Sunji Kurokawa 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).

  • Transmission interruption signal detection system
    Patent number: 4562483
    Abstract: In a transmission interruption signal detection system of a facsimile system transmitting image information from transmission apparatus to reception apparatus and producing a transmission interruption signal of a predetermined frequency and sending the same continuously for a predetermined period of time from the reception apparatus to the transmission apparatus when the reception apparatus is hung up, a hybrid transformer apparatus is provided, and transmission of the image information and reception of the transmission interruption signal are performed through the hybrid transformer apparatus, and signals having the predetermined frequency are extracted from signals obtained during transmission of the image information through the hybrid transformer apparatus and when the generation of the extracted signals continues for the predetermined period of time or longer, the transmission interruption detection signal is produced.
    Type: Grant
    Filed: September 7, 1979
    Date of Patent: December 31, 1985
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Kurokawa, Sunji Kurokawa, Yuichi Saito