Patents Assigned to McKinley Harrison Keyco
  • Patent number: 6874577
    Abstract: An auto-cycling plunger including a hollow, longitudinally extending body, at least one first directional outer seal, at least one second directional outer seal and a valve stem. Both the at least one first directional outer seal and the at least one second directional outer seal are disposed on an exterior surface of the body for creating a seal between the body and a well bore. Portions of the seals extend in a direction substantially parallel to the length of the longitudinally extending body such that these portions are spread resiliently outwardly from the body with an applied pressure, thereby increasing the degree of sealing. The first directional outer seal extending in a direction substantially opposite to the direction of the at least one second directional outer seal. The valve stem includes a valve member, extends through the longitudinally extending body, and has actual ends extending from the body. The valve stem is operable to be shuttled between an open and a closed position.
    Type: Grant
    Filed: September 12, 2003
    Date of Patent: April 5, 2005
    Assignee: McKinley Harrison Keyco
    Inventors: Douglas H. Abbott, Daniel S. Belczewski