Patent ID: 9689242
Date: 2017-06-27
CPC Classifications: E21B,F04B

Claim:
1. A plunger, comprising: a body comprising an upper end, a lower end, a bore extending axially from the upper end to the lower end, and a port therein that is in communication with at least a portion of the bore; an obstructing member positioned in the bore, the obstructing member comprising a valve stem, wherein the obstructing member is movable between a closed position, in which the obstructing member substantially prevents fluid flow through the bore from the port to the upper end, and an open position, in which fluid flow through the bore from the port to the upper end is permitted; an end nut connected to the lower end of the body; and a clutch assembly comprising a plurality of arcuate members that are positioned at least partially around and configured to engage the valve stem to impede movement thereof, the clutch assembly being positioned at least partially within the end nut.