Patent ID: 7716928

Claim:
An external combustion engine comprising: a main container containing a working fluid adapted to flow in liquid state; a heater for heating part of the working fluid in the main container and generating 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; wherein the heater, the cooler and the output unit are arranged in that order in the direction of displacement of the working fluid; wherein the auxiliary container containing the working fluid; wherein the auxiliary container communicates with the portion of the main container nearer the output unit than the cooler; the external combustion engine further comprising a communication area adjusting means for establishing communication between the main container and the auxiliary container through a first communication area in normal operation mode and establishing communication between the main container and the auxiliary container through a second communication area larger than the first communication area in engine starting mode.