Patents by Inventor Yuichi Iwasawa

Yuichi Iwasawa 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).

  • Device and method of performing a switching control to standby system in hybrid system of duplex system and backup line
    Patent number: 5581542
    Abstract: In a device and a method for performing a switching control to a standby system in a hybrid system including a duplex system and a backup line, communication is performed without using a backup line when a line is switched in an exchange. The device includes a first exchange having a pair of communication multiplexers and a communication line management processor. The backup line uses a public network. A second exchange is provided for interchanging between a line connected via the first exchange and the backup line using the public network. A normal notification signal is transmitted to the opposite communication party or second exchange when one of the communication multiplexers is switched to the standby system. A regulation releasing signal is transmitted after the switching operation so that communication is performed without using the backup line.
    Type: Grant
    Filed: May 27, 1994
    Date of Patent: December 3, 1996
    Assignee: Fujitsu Limited
    Inventors: Naoto Kato, Yuichi Iwasawa