Patents by Inventor Lucien Hehn

Lucien Hehn 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: 8513020
    Abstract: A system for sulfide stress cracking testing comprises an enclosed testing chamber including a fluid bath comprising a liquid saturated with hydrogen sulfide gas. In addition, the system comprises a test fixture disposed in the testing chamber and at least partially submerged in the fluid bath. The test fixture includes a housing having an internal chamber in fluid communication with the fluid bath and a test assembly disposed in the internal chamber. The test assembly comprises a first upper support and a second upper support, a first lower support and a second lower support, and a first platen engaging each of the upper supports and adapted to transfer an applied vertical load to the upper supports. Further, the system comprises a test specimen mounted in the test assembly between the upper supports and the lower supports.
    Type: Grant
    Filed: December 7, 2010
    Date of Patent: August 20, 2013
    Assignee: National Oilwell Varco, L.P.
    Inventors: Lucien Hehn, Kevin J. Wyble, Kenneth E. Casner, Jr., Kenneth E. Casner, Sr., Joseph Casner, George M. Waid
  • Publication number: 20110136239
    Abstract: A system for sulfide stress cracking testing comprises an enclosed testing chamber including a fluid bath comprising a liquid saturated with hydrogen sulfide gas. In addition, the system comprises a test fixture disposed in the testing chamber and at least partially submerged in the fluid bath. The test fixture includes a housing having an internal chamber in fluid communication with the fluid bath and a test assembly disposed in the internal chamber. The test assembly comprises a first upper support and a second upper support, a first lower support and a second lower support, and a first platen engaging each of the upper supports and adapted to transfer an applied vertical load to the upper supports. Further, the system comprises a test specimen mounted in the test assembly between the upper supports and the lower supports.
    Type: Application
    Filed: December 7, 2010
    Publication date: June 9, 2011
    Applicant: NATIONAL OILWELL VARCO, L.P.
    Inventors: Lucien Hehn, Kevin J. Wyble, Kenneth E. Casner, JR., Kenneth E. Casner, SR., Joseph Casner, George M. Waid
  • Patent number: 5245501
    Abstract: A process for controlling and measuring the movement of an armature of an electromagnetic switching member with an excitation coil is proposed, which has the following steps: a current (i) or a voltage (u1) is applied to the excitation winding (3) in order to move the armature into a first actuatable position; before the start of the movement of the armature, the current or the voltage is raised above a value at which the armature remains in the actuated position, and before termination of the movement of the armature the current or the voltage is reduced to a defined value, which suffices to hold the armature in the actuated position; finally, the temporal variations in the current or the voltage are measured after setting of the defined value, for the purpose of recognizing the termination of the armature movement.
    Type: Grant
    Filed: June 26, 1991
    Date of Patent: September 14, 1993
    Assignee: Robert Bosch GmbH
    Inventors: Johannes Locher, Hans-Joachim Siebert, Herbert Graf, Nestor Rodriguez-Amaya, Anton Karle, Alfred Schmitt, Joachim Tauscher, Werner Zimmermann, Dominique Buisson, Lucien Hehn, Pierre Lauvin, Henri Paganon
  • Patent number: 4979676
    Abstract: A fuel injection device for internal combustion engines having a high-pressure pump with a pump work chamber having a fuel injection valve with a pressure chamber, a pressure line connecting the pressure chamber with the pump work chamber. A relief conduit controlled by a relief valve which automatically blocks the relief conduit during the high-pressure phase and opened upon the beginning of the cutoff, for increasing a closing pressure exerted on the fuel injection valve after the end of the injection operation. The pressure line includes a pressure valve which opens in the supply direction and closes upon the beginning of the cutoff. The relief valve is urged in the opening direction by the pressure in the pressure chamber in the high-pressure chamber phase, and opens during flow of fuel from chamber in a direction toward the spring chamber of the injection valve simultaneously with a decrease in pressure in the pump work chamber.
    Type: Grant
    Filed: October 20, 1989
    Date of Patent: December 25, 1990
    Assignee: Robert Bosch GmbH
    Inventor: Lucien Hehn