Patent ID: 6705593
Filing Date: 2004-03-16
Classification: E21B,Y10T

Abstract:
An apparatus capable of moving a shiftable valve member mounted in a valve housing into a closed position and retaining it in the closed position, the valve housing having a bore and the shiftable valve member being moveable between at least one open and at least one closed position relative to the bore, the apparatus comprising:a first spring assembly engageable with the shiftable valve member, said first spring assembly being capable of at least partially moving the shiftable valve member into a closed position and assisting in retaining it in the closed position, and a second spring assembly including at least one elastically deformable member that extends at least partially around the circumference of the bore and is disposed at least partially in a cavity in the valve housing, said at least one elastically deformable member being elongated, having first and second ends and being connected to the shiftable valve member at one location and to the valve housing at at least one other location, whereby said at least one elastically deformable member is torsionally loaded to provide biasing, closing force to the shiftable valve member to assist in moving the shiftable valve member into a closed position and retaining the shiftable valve member in the closed position.