To reduce mechanical loss by ensuring mechanical balance among rotating sections and reciprocating motion sections for improving refrigeration capacity, and prevent deterioration and wear of oil bellows offsetting pressure variations in a buffer space and a crank chamber.

There can be driven integrally with one motor 27 left and right Stirling refrigerating machines 22, 22' with the same structure which comprises housings 23, 23' including crank chambers 26, 26', pressure cylinders 45, 45', compression pistons 48, 48', expansion cylinders 46, 46', expansion cylinders 55, 55', oil seals 53, 58, 53', 58', and buffer tanks 59, 59'.