Patents by Inventor Lars Fredrik Berg

Lars Fredrik Berg 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).

  • Device for producing plastic molded parts having a locking ring with a wear resistant material
    Patent number: 8684726
    Abstract: A device for producing plastic moldings has an extruder and a molding tool arranged downstream of an extruder discharge opening. A screw is rotatably guided in the extruder and is axially displaceable to transfer liquid polymers, prepolymers or monomers present in the extruder into the molding tool. A nonreturn valve adjacent to a free end of the screw has a locking ring in contact with the inner circumferential wall of the extruder that includes a seal, which is applied to at least part of its outer circumference and which seals the locking ring against the circumferential wall of the extruder. The sealing material of the seal is selected from the group of the polymers, copolymers and polymer blends with a hardness lower than that of the circumferential wall of the extruder. A nonreturn valve and method of processing liquid prepolymers or monomers into plastic moldings is provided.
    Type: Grant
    Filed: July 14, 2010
    Date of Patent: April 1, 2014
    Assignee: Fraunhofer-Gesellschaft zur Förderung der Angewandten Forschung E.V.
    Inventors: Lars Fredrik Berg, Bernd Thoma