Patent ID: 7617880

Claim:
An anchor assembly comprising: a mandrel having an upper end, a lower end, an outer wall surface, and a longitudinal bore disposed therethrough; an anchor setting sub-assembly disposed at the upper end of the mandrel and operatively associated with the mandrel along the outer wall surface of the mandrel, the anchor setting sub-assembly comprising a hydrostatic pressure actuatable anchor; an inflation sub-assembly disposed at the lower end of the mandrel and operatively associated with the mandrel along the outer wall surface of the mandrel, the inflation sub-assembly comprising a pump pressure actuatable valve having an opened position and a closed position, the opened position permitting fluid to flow through the bore of the mandrel; and an anchor release sub-assembly disposed between the anchor setting sub-assembly and the inflation sub-assembly and operatively associated with the anchor setting sub-assembly and the mandrel along the outer wall surface of the mandrel, the anchor release sub-assembly comprising a pump pressure actuatable mandrel release member, wherein hydrostatic pressure entering the bore of the mandrel actuates the anchor setting sub-assembly from a run-in position to a set position such that the anchor extends radially and engages an inner wall surface of a wellbore, a first positive pump pressure entering the bore of the mandrel actuates the valve of the inflation sub-assembly from the closed position to the opened position, and a second positive pump pressure entering the bore of the mandrel actuates the mandrel release member causing the anchor to retract from the set position to the run-in position, the second positive pump pressure being greater than the first positive pump pressure and the first positive pump pressure being greater than the hydrostatic pressure.