Patent ID: 8893798
Filing Date: 2014-11-25
Classification: E21B

Abstract:
1. An actuation assembly for a subterranean tool, comprising: a housing; an actuating member selectively extendable from said housing to operate the subterranean tool; an indexing assembly comprising a counter mechanism cyclically movable by a pressure cycle of pressure application and pressure removal in said housing, a first biasing member opposing movement of said indexing assembly due to said pressure application; said indexing assembly movable for a predetermined number of said pressure cycles without operating the subterranean tool; a boost force device retaining a predetermined mechanical potential force independent of pressure in said housing wherein said mechanical potential force is not applied to said actuating member during said predetermined number of pressure cycles; and wherein said mechanical potential force is delivered to said actuating member when said counter mechanism has had an incremental cycle beyond said predetermined number of pressure cycles thereby extending said actuating member from said housing.