Patents by Inventor John E. Dunstan

John E. Dunstan 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).

  • Encodable insert for a recording cassette
    Patent number: 4897750
    Abstract: Digital videocassettes are encoded by punching out breakaway tabs to permit a sensing mechanism on a recorder to identify key characteristics of each cassette. The encoding can be changed when the breakaway tabs are carried by an insert that can be remvably affixed to the cassettes. By employing such an insert, a number of problems are avoided such as possible contamination of the cassette and/or recorder by loose tabs. The tabs of the insert do not need to be breakaway when the inserts are initially formed to provide desired codes.
    Type: Grant
    Filed: May 9, 1988
    Date of Patent: January 30, 1990
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Robert L. Hanson, John E. Dunstan