Patents by Inventor David Louis Frantz

David Louis Frantz 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).

  • Heat-sealing wheels for forming a longitudinal weld or seal in seams of plastic films
    Patent number: 5935379
    Abstract: A heat seal wheel for use with a heat sealing apparatus associated with a continuous packaging machine, for forming a longitudinal seal in a flat sheet of flexible film. The heat seal wheel is characterized by a planar heater comprising a laminar resistive heating element sandwiched in between a top layer and a bottom layer of a thermally conductive and electrically insulative material. The top layer is bonded to the bottom surface a bearing disk, in contact with and supporting a rotating heat seal wheel for conductively heating the seal wheel and producing a heat seal in the seams of a moving web of plastic film.
    Type: Grant
    Filed: February 27, 1998
    Date of Patent: August 10, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: David Louis Frantz, Walter Ernest Lewis, Robert Vincent Jeral, Frederick Henry Fiesser