Patent ID: 7905090

Claim:
A steam engine comprising: a fluid container in which working fluid is filled and the working fluid can move; a heating device for heating the working fluid in the fluid container and vaporizing the working fluid to produce steam; a cooling device for cooling down liquefying the steam vaporized by the heating device; and an output device having a moving member reciprocating by pressure change of the working fluid in the fluid container, and outputting energy converted from the reciprocal movement of the moving member, wherein the fluid container comprises a pipe shaped portion having a heating portion at which the heating device is provided, and a cooling portion at which the cooling device is provided, wherein each of the heating portion and the cooling portion comprises multiple small pipe portions, wherein the heating device comprises a casing surrounding the heating portion of the fluid container, so that multiple small pipe portions of the heating portion are arranged in the casing in such a manner that each of the small pipe portions extends in a vertical direction, wherein a heating fluid flows through the inside of the casing in a horizontal direction to heat the heating portion of the fluid container, and wherein a surface area of the small pipe portions arranged at a downstream side of the heating fluid is made larger than that of the small pipe portions arranged at an upstream side of the heating fluid.