Patents by Inventor Karim Chouf

Karim Chouf 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: 9987709
    Abstract: The invention relates to a laser cutting method for cutting a stainless steel workpiece using laser beam generation means comprising a silica fiber with an ytterbium-doped core to generate the laser beam. Preferably, the laser beam generated by the ytterbium-based fiber has a wavelength between 1.07 and 1.09 ?m, a quality factor of the laser beam is between 0.33 and 8 mm·mrad, and the laser beam has a power of between 0.1 and 25 kW. The assistance gas for the laser beam is chosen from nitrogen, helium, argon and mixtures thereof, and, optionally, it further contains one or more additional compounds chosen from O2, CO2, H2 and CH4.
    Type: Grant
    Filed: February 2, 2015
    Date of Patent: June 5, 2018
    Assignee: L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude
    Inventors: Francis Briand, Karim Chouf, Hakim Maazaoui
  • Patent number: 9321131
    Abstract: The invention relates to a method for the laser welding of metal parts that comprises generating a CO2 laser beam, dispensing a protection gas jet made of said gas or gas mixture in the direction of the junction plane between the parts, melting and evaporating the metal of the metal parts with the laser beam in order to generate a metal vapor capillary with the simultaneous generation of a metal plasma that propagates outside the metal vapor capillary and thus forms a metal plasma plume above said junction plane. The protection gas jet is further directed towards the metal plasma plume forming above the junction plane. The gas jet is preferably directed so that the latter comes flush with the top of the metal plasma plume and impinges on the part(s) at a location where the metal of said parts has not been molten by the beam.
    Type: Grant
    Filed: September 3, 2009
    Date of Patent: April 26, 2016
    Assignee: L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude
    Inventors: Philippe Lefebvre, Karim Chouf
  • Publication number: 20150174701
    Abstract: The invention relates to a laser cutting method for cutting a stainless steel workpiece using laser beam generation means comprising a silica fibre with an ytterbium-doped core to generate the laser beam. Preferably, the laser beam generated by the ytterbium-based fibre has a wavelength between 1.07 and 1.09 ?m, a quality factor of the laser beam is between 0.33 and 8 mm·mrad, and the laser beam has a power of between 0.1 and 25 kW. The assistance gas for the laser beam is chosen from nitrogen, helium, argon and mixtures thereof, and, optionally, it further contains one or more additional compounds chosen from O2, CO2, H2 and CH4.
    Type: Application
    Filed: February 2, 2015
    Publication date: June 25, 2015
    Inventors: Francis BRIAND, Karim CHOUF, Hakim MAAZAOUI
  • Patent number: 8710400
    Abstract: The invention relates to a laser cutting method for cutting a C—Mn steel workpiece, characterized in that laser beam generation means comprising at least one silica fiber with an ytterbium-doped core is used to generate the laser beam. Preferably, the ytterbium-based fiber has a wavelength between 1.07 and 1.1 ?m, preferably 1.07 ?m, the quality factor of the laser beam is between 0.33 and 8 mm.mrad, and the laser beam has a power of between 0.1 and 25 kW. The assistance gas for the laser beam is chosen from nitrogen, helium, argon, oxygen, CO2 and mixtures thereof, and, optionally, it further contains one or more additional compounds chosen from H2 and CH4.
    Type: Grant
    Filed: June 2, 2011
    Date of Patent: April 29, 2014
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Francis Briand, Karim Chouf, Hakim Maazaoui
  • Patent number: 8378253
    Abstract: The invention relates to a method for welding with a laser beam, using a welding nozzle comprising: a nozzle body having an axis and including at least an upper surface, a lower surface and a peripheral wall; an axial cavity extending between the upper and lower surfaces of the nozzle body so as to define an outer channel recessed from the surface of said peripheral wall; and a plurality of inner passages drilled through the nozzle body between the upper and lower surfaces. The laser welding method of the invention provides a dynamic gas jet mechanically interacting with the molten metal bath, and further enables better control of the bath hydrodynamic flows, and thus better laser-welding efficiency.
    Type: Grant
    Filed: December 16, 2008
    Date of Patent: February 19, 2013
    Assignee: L'Air Liquide Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Karim Chouf, Philippe Lefebvre
  • Patent number: 8278591
    Abstract: The invention relates to method for cutting a part using a laser beam, involving the use of laser beam generation means comprising at least one ytterbium-based fibre having a wavelength of between 1 and 4 ?m in order to generate the laser beam. The laser beam is selected to have a power of less than 100 kW, a power density of at least 1 MW/cm2, a focused beam diameter of at least 0.1 mm and a quality factor (BPP) of less than 10 mm·mrad.
    Type: Grant
    Filed: January 22, 2007
    Date of Patent: October 2, 2012
    Assignee: L'Air Liquide Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Karim Chouf, Hakim Maazaoui, Eric Verna, Françis Briand
  • Publication number: 20120024831
    Abstract: The invention relates to a laser cutting method for cutting a stainless steel workpiece using laser beam generation means comprising a silica fibre with an ytterbium-doped core to generate the laser beam. Preferably, the laser beam generated by the ytterbium-based fibre has a wavelength between 1.07 and 1.09 ?m, a quality factor of the laser beam is between 0.33 and 8 mm.mrad, and the laser beam has a power of between 0.1 and 25 kW. The assistance gas for the laser beam is chosen from nitrogen, helium, argon and mixtures thereof, and, optionally, it further contains one or more additional compounds chosen from O2, CO2, H2 and CH4.
    Type: Application
    Filed: June 2, 2011
    Publication date: February 2, 2012
    Applicants: La Soudure Autogene Francaise (Air Liquide Welding France), L'Air Liquide Societe Anonyme Pour I'Etude et I'Exploitation des Procedes Georges Claude
    Inventors: Francis BRlAND, Karim CHOUF, Hakim MAAZAOUI
  • Publication number: 20120012570
    Abstract: The invention relates to a laser cutting method for cutting a C—Mn steel workpiece, characterized in that laser beam generation means comprising at least one silica fiber with an ytterbium-doped core is used to generate the laser beam. Preferably, the ytterbium-based fiber has a wavelength between 1.07 and 1.1 ?m, preferably 1.07 ?m, the quality factor of the laser beam is between 0.33 and 8 mm.mrad, and the laser beam has a power of between 0.1 and 25 kW. The assistance gas for the laser beam is chosen from nitrogen, helium, argon, oxygen, CO2 and mixtures thereof, and, optionally, it further contains one or more additional compounds chosen from H2 and CH4.
    Type: Application
    Filed: June 2, 2011
    Publication date: January 19, 2012
    Applicants: L'Air Liquide Welding France (La Soudure Autogéne Française, L'Air Liquide Société Anonyme pour I'Etude et I'Exploitation des Procédés Georges Claude
    Inventors: Francis Briand, Karim Chouf, Hakim Maazaoui
  • Publication number: 20110174786
    Abstract: The invention relates to a method for the laser welding of metal parts that comprises generating a CO2 laser beam, dispensing a protection gas jet made of said gas or gas mixture in the direction of the junction plane between the parts, melting and evaporating the metal of the metal parts with the laser beam in order to generate a metal vapor capillary with the simultaneous generation of a metal plasma that propagates outside the metal vapor capillary and thus forms a metal plasma plume above said junction plane. The protection gas jet is further directed towards the metal plasma plume forming above the junction plane. The gas jet is preferably directed so that the latter comes flush with the top of the metal plasma plume and impinges on the part(s) at a location where the metal of said parts has not been molten by the beam.
    Type: Application
    Filed: September 3, 2009
    Publication date: July 21, 2011
    Inventors: Philippe Lefebvre, Karim Chouf
  • Publication number: 20100282723
    Abstract: The invention relates to a method for welding with a laser beam, using a welding nozzle comprising: a nozzle body having an axis and including at least an upper surface, a lower surface and a peripheral wall; an axial cavity extending between the upper and lower surfaces of the nozzle body so as to define an outer channel recessed from the surface of said peripheral wall; and a plurality of inner passages drilled through the nozzle body between the upper and lower surfaces. The laser welding method of the invention provides a dynamic gas jet mechanically interacting with the molten metal bath, and further enables better control of the bath hydrodynamic flows, and thus better laser-welding efficiency.
    Type: Application
    Filed: December 16, 2008
    Publication date: November 11, 2010
    Applicant: L'Air Liquide Societe Anonyme Pour L'Etude Et L'Exploitation Des Procedes Georges Claude
    Inventors: Karim Chouf, Philippe Lefebvre
  • Publication number: 20090218326
    Abstract: The invention relates to method for cutting a part using a laser beam, involving the use of laser beam generation means comprising at least one ytterbium-based fibre having a wavelength of between 1 and 4 ?m in order to generate the laser beam. The laser beam is selected to have a power of less than 100 kW, a power density of at least 1 MW/cm2, a focused beam diameter of at least 0.1 mm and a quality factor (BPP) of less than 10 mm·mrad.
    Type: Application
    Filed: January 22, 2007
    Publication date: September 3, 2009
    Applicant: L'AIR LIQUIDE SOCIETE ANONYME POUR L'EPLOITATION DES PROCEDES GEORGES CLADUE
    Inventors: Karim Chouf, Hakim Maazaoui, Erie Verna, Francis Briand
  • Patent number: 7385158
    Abstract: A method and an apparatus for welding with a laser beam. A shielding gas mixture of nitrogen and helium is used and the proportions of the component gases are modified depending on the laser beam's power or power density. Plasma formation in the shield gas is minimized by increasing the proportion of helium as the laser beam's power or power density increases.
    Type: Grant
    Filed: December 4, 2002
    Date of Patent: June 10, 2008
    Assignee: L'Air Liquide, Societe Anonyme a Directoire et Conseil de Surveillance pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Francis Briand, Karim Chouf, Philippe Lefebvre
  • Publication number: 20070119833
    Abstract: The invention relates to a laser cutting method for cutting a C-Mn steel workpiece, characterized in that laser beam generation means comprising at least one silica fiber with an ytterbium-doped core is used to generate the laser beam. Preferably, the ytterbium-based fiber has a wavelength between 1.07 and 1.1 ?m, preferably 1.07 ?m, the quality factor of the laser beam is between 0.33 and 8 mm.mrad, and the laser beam has a power of between 0.1 and 25 kW. The assistance gas for the laser beam is chosen from nitrogen, helium, argon, oxygen, CO2 and mixtures thereof, and, optionally, it further contains one or more additional compounds chosen from H2 and CH4.
    Type: Application
    Filed: November 15, 2006
    Publication date: May 31, 2007
    Applicants: L'Air Liquide Societe Anonyme pour I'Etude et I'Exploitation des Procedes Georges Claude, Air Liquide Welding France (La Soudure Autogene Francaise)
    Inventors: Francis Briand, Karim Chouf, Hakim Maazaoui
  • Publication number: 20070119834
    Abstract: The invention relates to a laser cutting method for cutting a stainless steel workpiece using laser beam generation means comprising a silica fibre with an ytterbium-doped core to generate the laser beam. Preferably, the laser beam generated by the ytterbium-based fibre has a wavelength between 1.07 and 1.09 ?m, a quality factor of the laser beam is between 0.33 and 8 mm.mrad, and the laser beam has a power of between 0.1 and 25 kW. The assistance gas for the laser beam is chosen from nitrogen, helium, argon and mixtures thereof, and, optionally, it further contains one or more additional compounds chosen from O2, CO2, H2 and CH4.
    Type: Application
    Filed: November 15, 2006
    Publication date: May 31, 2007
    Applicants: L'Air Liquide Societe Anonyme pour I'Etude et I'Exploitation des Procedes Georges Claude, La Soudure Autogene Francaise (Air Liquide Welding France)
    Inventors: Francis Briand, Karim Chouf, Hakim Maazaoui
  • Publication number: 20060196859
    Abstract: Methods for laser beam cutting metal workpieces with a thickness between 4 mm and 25 mm. A double focusing lens is provided to make it possible to focus a laser beam on a first focusing and a second focusing point. These points are separate from each other and both lie on the laser's optical axis. The lens has a focal length between 170 mm and 300 mm.
    Type: Application
    Filed: January 3, 2006
    Publication date: September 7, 2006
    Inventors: Christophe Bertez, Karim Chouf, Hakim Maazaoui
  • Publication number: 20060186099
    Abstract: The invention relates to a method for laser-beam cutting a metal workpiece having a thickness of less than 5 mm, in which a double focusing lens is employed making it possible to focus the laser beam at least at a first focusing point (PF1) and a second focusing point (PF2) which are separate from each other and lie on the beam axis, characterized in that the lens has a focal length (FL) of between 80 and 135 mm.
    Type: Application
    Filed: January 3, 2006
    Publication date: August 24, 2006
    Inventors: Christophe Bertez, Karim Chouf, Hakim Maazaoui
  • Patent number: 7038163
    Abstract: Binary gas mixture for welding using a laser beam of up to 12 kW, consisting of 30% to 60% nitrogen by volume, the remainder (up to 100%) being helium. Application of this gas mixture to the welding of steel, stainless steel or titanium.
    Type: Grant
    Filed: June 9, 2003
    Date of Patent: May 2, 2006
    Assignee: L'air liquide, societe anonyme a directoire et conseil de surveillance pour l'etude et l'exploitation des procedes georges claude
    Inventors: Francis Briand, Karim Chouf, Philippe Lefebvre, Eric Verna
  • Publication number: 20060081568
    Abstract: Binary gas mixture for welding using a laser beam of up to 12 kW, consisting of 30% to 60% nitrogen by volume, the remainder (up to 100%) being helium. Application of this gas mixture to the welding of steel, stainless steel or titanium.
    Type: Application
    Filed: November 2, 2005
    Publication date: April 20, 2006
    Inventors: Francis Briand, Karim Chouf, Philippe Lefebvre, Eric Verna
  • Publication number: 20050167406
    Abstract: A method and an apparatus for welding with a laser beam. A shielding gas mixture of nitrogen and helium is used and the proportions of the component gases are modified depending on the laser beam's power or power density. Plasma formation in the shield gas is minimized by increasing the proportion of helium as the laser beam's power or power density increases.
    Type: Application
    Filed: December 4, 2002
    Publication date: August 4, 2005
    Inventors: Francis Briand, Karim Chouf, Philippe Lefebvre
  • Publication number: 20050016971
    Abstract: The invention relates to a laser beam welding method and installation that makes use of a protective gas mixture containing argon and helium. The proportion of argon and/or helium in said gas mixture is chosen or adjusted according to the power or the power density of the laser beam. The laser power is included between 0.5 kW and 30 kW and, preferably, between 5 kW and 20 kW. The protective gas mixture comprises argon and/or helium and, preferably, the gas mixture contains a volume proportion of helium of between 30% and 80%, the remainder being argon and, possibly, inevitable impurities.
    Type: Application
    Filed: May 24, 2002
    Publication date: January 27, 2005
    Inventors: Francis Briand, Karim Chouf, Philippe Lefebvre