Patent ID: 7891184

Claim:
A 4-cycle Stirling machine of an alpha type, comprising: first and second double-piston units being moved to one another with a phase shift, wherein each of the double-piston units includes (a) a double-acting expansion piston being firmly connected to a double-acting compression piston via a piston rod and (b) a piston rod extension being firmly connected at a first end to the compression piston, the piston rod extension being mechanically connected to a gear at a second end and wherein a generator is positioned between the piston rod extensions of the double-piston units, wherein a first cylinder space above the first expansion piston is connected to a second cylinder space above the second compression piston via a first heater-regenerator-cooler assembly, wherein a third cylinder space below the first expansion piston is connected to a fourth cylinder space below the second compression piston via a second heater-regenerator-cooler assembly, wherein the fifth cylinder space above the second expansion piston is connected to the sixth cylinder space below the first compression piston via a third heat source-regenerator-cooler assembly, and wherein the seventh cylinder space below the second expansion piston is connected to the eighth cylinder space above the first compression piston via a fourth heat source-regenerator-heat sink assembly.