Patents by Inventor Yasuo Kumakura

Yasuo Kumakura 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).

  • Matrix switching device and method of manufacturing the same
    Patent number: 5017145
    Abstract: A matrix switching device includes a matrix board and a connecting pin. X-conductor patterns are arranged in parallel with each other on one surface of the matrix board, and Y-conductor patterns are arranged in parallel with each other on the other surface. Both the patterns are arranged in a matrix form. At each crossing point of the both patterns, a through hole having conductive portions respectively connected to the X- and Y-conductor patterns and an intermediate isolation portion for interrupting conduction between the conductive portions is formed in the matrix board. The connecting pin includes conductive portions respectively electrically connected to the X- and Y-conductor patterns through the conductive portions of the through hole upon insertion of the connecting pin into the through hole.
    Type: Grant
    Filed: April 24, 1989
    Date of Patent: May 21, 1991
    Assignee: Nippon Telegraph & Telephone Corporation
    Inventors: Tsuneo Kanai, Shigefumi Hosokawa, Yasuo Kumakura, Shigeru Umemura, Shuichiro Inagaki