Patents Assigned to Lufkin Industries, LLC
  • Patent number: 8894286
    Abstract: A damper film bearing assembly for supporting a rotatable shaft includes a bearing housing having a longitudinal opening passing therethrough for receiving the rotatable shaft. The bearing housing also has at least one radial recess formed in an outer surface thereof. At least one resilient element is disposed within the recess in the bearing housing above the floor of the recess, the resilient element biasing the support piston away from the axis of the rotatable shaft. The resilient element in accordance with the disclosure may be a bridge spring or a rod spring as appropriate.
    Type: Grant
    Filed: November 23, 2011
    Date of Patent: November 25, 2014
    Assignee: Lufkin Industries, LLC
    Inventors: John C. Nicholas, Thomas P. Shoup, Donald H. Rockefeller
  • Patent number: 8678082
    Abstract: A pumping arrangement employs a compensating type hydraulic pump, a directional valving arrangement and a proportioning valving arrangement. When the directional valve is energized, oil is directed to the rod end of the hydraulic cylinder. The rod or piston part of the hydraulic cylinder will then elevate until a first limit switch is actuated which then will de-energize the directional valve and send a current signal to the proportional valve. This current signal to the proportional valve forces it to open to a point at which the cylinder rod would extend at the desired velocity until it reaches a second limit switch. The current signal to the proportional valve is then decreased, creating a choking arrangement that forces the cylinder rod to decelerate. Upon reaching the third limit switch, the signal is removed from the proportional valve so that it closes.
    Type: Grant
    Filed: August 7, 2012
    Date of Patent: March 25, 2014
    Assignee: Lufkin Industries, LLC
    Inventors: Michael A. Fesi, Willard J. Lapeyrouse, Kenneth H. Vincent