Patent ID: 8322426

Claim:
A downhole actuator apparatus comprising: a body defining first and second chambers and a fluid path between first and second pressure regions; a piston slidably disposed in the body and selectively moveable between first and second positions, in the first position, the piston blocking fluid communication between the first and second pressure regions and the first chamber and between the first pressure region and second pressure region, in the second position, the piston blocking fluid communication between the first and second pressure regions and the first chamber and allowing fluid communication between the first pressure region and second pressure region; a barrier disposed in the body and selectively separating the first and second chambers; a fluid disposed in the first chamber between the barrier and the piston; and a control system at least partially disposed within the body, the control system operable to generate an output signal responsive to receipt of a predetermined input signal, the output signal operable to create a failure of the barrier such that at least a portion of the fluid flows from the first chamber to the second chamber and the piston moves from the first position to the second position, thereby allowing fluid communication between the first and second pressure regions.