Patent ID: 7114334

Claim:
A Stirling cycle machine operating via the compression and expansion of a working fluid, said Stirling cycle machine comprising: an expansion chamber defined in a first cylinder by a piston; a compression chamber defined in a second cylinder by said piston; said expansion chamber and said compression chamber in communication via at least one passageway; said passageway comprising a heat exchanger, said heat exchanger including an impingement baffle arranged to direct said working fluid so as to provide a higher heat transfer function when said working fluid flows in a first direction, due to the impingement baffle causing impingement of the working fluid on a heat transfer surface during flow in the first direction, as opposed to a lower heat transfer function when said working fluid flows in a second direction, due to said working fluid flowing past the heat transfer surface and through the impingement baffle away from the heat transfer surface during flow in the second direction.