Patents by Inventor Edward L. Libby

Edward L. Libby 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).

  • Patent number: 5045378
    Abstract: A scribed paperboard sheet and a method for its manufacture is characterized by scribing a plurality of parallel guidelines in a finished paperboard web while the web is being tensioned. Adjustable scribing knife assemblies are provided for simultaneously scribing both surfaces of the web, following which the web of scribed paperboard is cut into individual sheets. The depth of penetration and the lateral spacing of the scribing knives are controlled to define a particular scribed layout of lines in the surfaces of the paperboard sheets. Alternatively, a grid of guidelines may be scribed into the web by an embossed roller arranged adjacent a tension roller to define a nip through which the paperboard web passes.
    Type: Grant
    Filed: May 2, 1989
    Date of Patent: September 3, 1991
    Assignee: Specialty Paperboard Inc.
    Inventor: Edward L. Libby