Patents by Inventor Francis J. Dwan

Francis J. Dwan 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).

  • Electrical keying for replaceable modules
    Patent number: 4800462
    Abstract: An electrical keying system for a set of incompatible module pairs to prevent powerup of an electrically incompatible module pair in a set.
    Type: Grant
    Filed: April 17, 1987
    Date of Patent: January 24, 1989
    Assignee: Tandem Computers Incorporated
    Inventors: A. Richard Zacher, Jay A. Zwagerman, Francis J. Dwan