Patent ID: 7644582

Claim:
An external combustion engine comprising: a container containing a working medium adapted to flow in liquid phase and including one collecting pipe and a multiplicity of branch pipes branching from the collecting pipe; a multiplicity of evaporators communicating with the end of the multiplicity of the branch pipes far from the collecting pipe for heating and evaporating part of the working medium in liquid phase; a multiplicity of condensers formed in at least a part of the multiplicity of the branch pipes for cooling and condensing the working medium evaporated in the evaporators; and an output unit communicating with the end of the collecting pipe far from the multiplicity of the branch pipes for converting the displacement of the liquid-phase portion of the working medium into mechanical energy and outputting the energy; wherein the multiplicity of the evaporators are supplied with heat from a common heat source; and wherein a first process for displacing the liquid-phase portion of the working medium toward the output unit by evaporating the working medium in the multiplicity of the evaporators alternates with a second process for displacing the liquid-phase portion of the working medium toward the multiplicity of the evaporators by condensing the working medium evaporated in the first process in the multiplicity of the condensers; the external combustion engine further comprising an influent liquid amount regulation means wherein the influent liquid amount, defined as the amount of the liquid-phase portion of the working medium flowing into any one of the multiplicity of the evaporators upon displacement of the liquid-phase portion of the working medium from the output unit toward the multiplicity of the evaporators in the second process, is so regulated that the influent liquid amount is larger for the evaporators nearer the heat source, and smaller for the evaporators farther from the heat source.