Patents by Inventor Alfred Feldkamp

Alfred Feldkamp 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).

  • Metal-plastic multilayer pipe having form stability for plumbing and hydronic heating
    Patent number: 6604552
    Abstract: Metal-plastic multilayer pipe with a plastic inner pipe (30) and a metal sheath (32) around the plastic inner pipe (30), where the metal sheath (32) is of uniform thickness, is applied to the plastic inner pipe (30) so that it completely encircles the plastic inner pipe (30) and a practical plastic outer layer (38), with the feature that the thickness of the metal sheath (32) as compared to the total thickness of all layers of the multilayer pipe (32, 34 and 38), is sufficiently thin that the metal sheath (32) accounts for a negligible part of the overall strength and stiffness of the multilayer pipe and, as a consequence, when the multilayer pipe is bent in an arc, the metal sheath (32) offers negligible resistance to such bending as compared to the resistance offered by the inner pipe (30) and the practical cover layer (38), and when so bent, the multilayer pipe tends to remain bent in said arc, whereby, the multilayer pipe has “form stability”.
    Type: Grant
    Filed: March 28, 2001
    Date of Patent: August 12, 2003
    Inventors: Jorg Hansen, Reinhold Freermann, Alfred Feldkamp, Franz-Josef Riesselmann
  • Metal-plastic multilayer pipe having form stability for plumbing and hydronic heating
    Publication number: 20020007861
    Abstract: Metal-plastic multilayer pipe with a plastic inner pipe (30) and a metal sheath (32) around the plastic inner pipe (30), where the metal sheath (32) is of uniform thickness, is applied to the plastic inner pipe (30) so that it completely encircles the plastic inner pipe (30) and a practical plastic outer layer (38), with the feature that the thickness of the metal sheath (32) as compared to the total thickness of all layers of the multilayer pipe (32, 34 and 38), is sufficiently thin that the metal sheath (32) accounts for a negligible part of the overall strength and stiffness of the multilayer pipe and, as a consequence, when the multilayer pipe is bent in an arc, the metal sheath (32) offers negligible resistance to such bending as compared to the resistance offered by the inner pipe (30) and the practical cover layer (38), and when so bent, the multilayer pipe tends to remain bent in said arc, whereby, the multilayer pipe has “form stability”.
    Type: Application
    Filed: March 28, 2001
    Publication date: January 24, 2002
    Inventors: Jorg Hansen, Reinhold Freermann, Alfred Feldkamp, Franz-Josef Riesselmann