Pressure equalization system for a stirling engine

摘要

A working gas control system for a double acting type Stirling engine having two or more piston assemblies reciprocating within bores. Each of the piston assemblies separate isolated cycle volumes of a working gas which undergoes cyclical pressure variations. The pressure equalization system includes forming isolated first and second volumes with the first volume maintained at a low pressure through the use of a check valve. The second volume is maintained at a pressure intermediate of the minimum and maximum pressures of the cycle volumes. By providing controlled leakage paths between the volumes, the mass or volume of working gas in each of the cycle volumes can be maintained in a balanced condition despite minor leakages outside the engine of the working gas and leakage past the piston assemblies separating the cycle volumes. Additional features further include the provision of a control valve which acts to unload the engine for starting or shut down, and further can provide the functions of a check valve and a control leakage path within the engine.