Patents by Inventor Mitsunobu Nagao

Mitsunobu Nagao 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).

  • Method and apparatus for line switching
    Patent number: 5483519
    Abstract: A line switching apparatus for switching from a telecommunication line to a backup line in the event of occurrence of a fault on the telecommunication line includes a memory storing time zone information for monitoring the state of the telecommunication line, so that, when occurrence of a fault is detected during this monitoring time zone, the line switching apparatus switches from the faulty telecommunication line to a backup line, while when the time is outside the monitoring time zone, the state of the telecommunication line is not monitored so as to prevent unnecessary switching from the telecommunication line to the backup line.
    Type: Grant
    Filed: May 17, 1994
    Date of Patent: January 9, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Shigeki Satomi, Mitsunobu Nagao, Naoki Ono