Patent ID: 7134279

Claim:
A Stirling system comprising: a plurality of double-acting non-fluidic free-pistons; a plurality of overstroke preventers, each coupled to at least a different one of the pistons; a plurality of cylinders, each having a different one of the pistons positioned therein for reciprocal motion, each of the cylinders coupled to a different corresponding pair of other ones of the cylinders to fluidly couple the cylinder to a first cylinder and a second cylinder of the corresponding pair; and a Stirling cycle working fluid, portions of the Stirling cycle working fluid positioned in the cylinders and in contact with the pistons, the reciprocal motion of the piston positioned in each of the cylinders being coupled to the reciprocal motion of the piston positioned in the first cylinder of the corresponding pair solely through the Stirling cycle working fluid and being coupled to the reciprocal motion of the piston positioned in the second cylinder of the corresponding pair solely through the Stirling cycle working fluid.