Patents by Inventor Gerhard Bobertag

Gerhard Bobertag 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: 4150934
    Abstract: An apparatus for manufacturing axially symmetrical solid bodies such as ear plugs or sealing members made of a soft resilient expanded plastics foam material wherein a die adapted to cooperate with a cutting matrix for punch-pressing is provided with means for pre-stressing the punched foam material prior to the actual cutting operation for obtaining bodies of different shapes. This pre-stressing means may consist of a dowel, a recess or a curved surface at the die head and/or projections, bevel surfaces, vacuum chambers at the cutting table. The die may be cylindrical, annular, square or of any other desired configuration.
    Type: Grant
    Filed: December 15, 1977
    Date of Patent: April 24, 1979
    Assignees: Bobertag und Hausler GmbH, Gehorschutzcenter Wilhelm und Claus-Dieter Harms GmbH
    Inventors: Gerhard Bobertag, Bernfried Dihse, Claus D. Harms, Uwe Gatzemann, Wilhelm Harms