Patent ID: 8662187

Claim:
A tubing pressure insensitive actuator system comprising: a housing having a bore therein; a force transmitter sealingly moveable within the bore the force transmitter defining with the bore two fluid chambers, one at each longitudinal end of the force transmitter; at least two seals sealingly positioned between the housing and the force transmitter, one of the seals isolating one end of the force transmitter from tubing pressure and another of the seals isolating another end of the force transmitter from tubing pressure; an activator having: a permanent magnet carrier; a plurality of permanent magnets mounted to the permanent magnet carrier; a coil carrier disposed in magnetic field proximity to the permanent magnet carrier; and a plurality of coils mounted to the coil carrier, one of the permanent magnet carrier and the coil carrier being movable relative to the other of the permanent magnet carrier and coil carrier, and being connected to the force transmitter.