Patents by Inventor Pierre Lefebvre

Pierre Lefebvre 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).

  • Method of making a seamless hot-finished steel pipe, and device for carrying out the method
    Patent number: 8166792
    Abstract: In a method of making a seamless hot-finished steel pipe a billet heated to a shaping temperature is pierced by a first shaping to a thick-walled hollow ingot which subsequently undergoes a radial forging process using an internal tool inserted in the hollow ingot and at least two forging jaws of a forging machine. The forging jaws act on the outer surface area of the hollow ingot, wherein the hollow ingot is turned and axially advanced in a clocked manner in the idle stroke phase of the forging jaws.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: May 1, 2012
    Assignee: V & M Deutschland GmbH
    Inventors: Christoph Prasser, Rolf Kümmerling, Stefan Wiedenmaier, Pierre Lefebvre, Rupert Wieser, Robert Koppensteiner
  • FORGING MANDREL FOR HOT-FORGING TUBULAR WORKPIECES OF METAL
    Publication number: 20100251794
    Abstract: The invention relates to a forging mandrel for hot-forging tubular workpieces of metal, said mandrel comprising a mandrel body and a mandrel bar, in which forging mandrel the mandrel body is composed of a heat-resistant material. The forging mandrel according to the invention is embodied here in such a way that the mandrel body is provided, at least in the work zone, with a layer which reduces the dissipation of heat into the mandrel body during the forging process and adheres firmly to the mandrel body, wherein the layer has a lower thermal conductivity than the material of the mandrel body and has a thickness of at least 50 ?m.
    Type: Application
    Filed: June 25, 2008
    Publication date: October 7, 2010
    Applicant: V & M DEUTSCHLAND GMBH
    Inventors: Stefan Wiedenmaier, Rolf Kümmerling, Gerd Homberg, Pierre Lefebvre
  • METHOD OF MAKING A SEAMLESS HOT-FINISHED STEEL PIPE, AND DEVICE FOR CARRYING OUT THE METHOD
    Publication number: 20090044883
    Abstract: In a method of making a seamless hot-finished steel pipe a billet heated to a shaping temperature is pierced by a first shaping to a thick-walled hollow ingot which subsequently undergoes a radial forging process using an internal tool inserted in the hollow ingot and at least two forging jaws of a forging machine. The forging jaws act on the outer surface area of the hollow ingot, wherein the hollow ingot is turned and axially advanced in a clocked manner in the idle stroke phase of the forging jaws.
    Type: Application
    Filed: October 25, 2005
    Publication date: February 19, 2009
    Applicant: V & M DEUTSCHLAND GMBH
    Inventors: Christoph Prasser, Rolf Kummerling, Stefan Wiedenmaier, Pierre Lefebvre, Rupert Wieser, Robert Koppensteiner
  • Poppet valve for internal combustion engine
    Patent number: 4981118
    Abstract: A poppet valve for an internal combustion engine, comprising at least two valve stems and a single non circular valve head attached at one end of the valve stems wherein the stems are spacedly parallel to each other. The valve head has an oval or semi-circular peripheral contour for maximum cylinder breathing. The valve stems positively prevent valve head rotation and define a high surface to volume ratio, for increased heat dissipation capacity.
    Type: Grant
    Filed: April 12, 1990
    Date of Patent: January 1, 1991
    Inventor: Pierre Lefebvre