Patent ID: 8739864

Claim:
A tool for use in subterranean hydrocarbon production, the tool comprising: a housing defining an axial flow bore; a piston sleeve axially moveably disposed within the flow bore between a first position corresponding to a first operating position for the tool, and a second position corresponding to a second operating position for the tool; an actuation mechanism for moving the tool between the first and second operating positions, the actuation mechanism comprising a ball seat carried by the piston sleeve, the ball seat being formed of dogs upon which an actuation ball can rest and that are moveable radially inwardly and outwardly to capture and release said actuation ball; wherein: a) the actuation mechanism moves the tool from the first operating position to the second operating position by landing a first actuation ball onto the ball seat and thereafter varying fluid pressure within the flow bore of the housing; b) the actuation mechanism moves the tool from the second operating position to the first operating position by landing a second actuation ball that is of a different size than the first actuation ball onto the ball seat after the first actuation ball has been released from the ball seat and thereafter varying fluid pressure within the flow bore of the housing; and an indexing mechanism that governs the axial position of the piston sleeve with respect to the housing, the indexing mechanism comprising: a) an annular lug pathway having positions corresponding to the tool operating positions; and b) a lug that moves within the lug pathway as the tool is moved between operating positions.