Patent attributes
An external combustion engine includes: a main container sealed with a working fluid in a liquid state adapted to flow; a heater for heating a portion of the working fluid in the main container and generating the vapor of the working fluid; a cooler for cooling and liquefying the vapor; an output unit for outputting by converting the displacement of the liquid portion of the working fluid generated by the volume change of the working fluid due to the generation and liquefaction of the vapor into mechanical energy; and an auxiliary container communicating with the main container. The heater, the cooler and the output unit are arranged in order, in the direction of displacement of the working fluid. The working fluid is sealed in the auxiliary container which communicates with the portion of the main container nearer the output unit than the cooler. The engine further includes a communication area adjusting unit for establishing communication between the main container and the auxiliary container with a first communication area in normal operation mode and with a second communication area larger than the first communication area at the time of engine start. Thus, a predetermined output is produced quickly after engine start.