Stirling engine

A Stirling engine wherein a pressure variation is provided by reciprocative movement of a displacer and is utilized by a power piston to obtain an output motive force, which comprises:

• a pressurized crankcase,
• an expansion cylinder having a seal carrying wall,
• a displacer located in said expansion cylinder,
• a displacer rod connected to said displacer and projecting through said seal and into said crankcase,
• a first elastic film attached to said displacer rod and to said seal carrying wall so as to produce a first hermetically sealed space,
• a compression cylinder,
• a power pistion having a power pistion rod located in said compression cylinder,
• a second elastic film attached to said power piston rod and to said compression cylinder so as to produce a second hermetically sealed space below said power piston,
• said first and said second hermetically sealed spaces being included in a pressurized reactive space,
• a pressure adjusting means for equalizing the mean pressure within said reactive space and the mean pressure within said crankcase,
• a heater tube, a regenerator, and a cooler tube are connected to said expansion cylinder, and are included in a working space, as is the expansion cylinder and the compression cylinder, and
• a first gas having a low viscosity, a low molecular weight and a high thermal conductivity is sealed in said working space and said reactive space, and a second gas having a high viscosity and a high molecular weight is sealed in said crankcase.