Abstract: A combustion heater/pot combination for rapid and efficient heating of liquids and foodstuffs comprises a cylindrical shell enclosing both a heat source and a container whereby products of combustion are constrained to flow through an annular flue defined by the shall wall and the container within and spaced from the shell wall by guide elements. The shell is elevated above a support surface, such as the ground or a hearth, by a plurality of struts, whereby air is admitted to a combustion zone. The struts are releasably engaged to the shell by structures which assure stability of attachment. Combustion air preheat and/or draft control shells resting on the support surface may embrace the shell strut combination for improved efficiency.

Abstract: A cooker and/or radiant-heating space heater system comprises a plurality of arcuate sheet metal shell segments assembled with overlapping edge portions so as to form a substantially cylindrical inner shell surrounded by a plurality of similarly overlapping arcuate segments which may be spaced selectively relative to the inner shell and to each other so as to vary the spaces thus defined between the inner shell and the outer segments. The inner shell is spaced above a support surface such as the ground, and the outer segments rest on the support surface so that a combustion zone within the inner shell is in communication with the spaces between the inner shell and the outer segments. For highly efficient combustion, air is drawn down such spaces, due to negative pressure induced by convection over a fire within the combustion zone, and preheated through contact with the hot inner shell prior to entering the combustion zone.

Abstract: A furnace or furnace-and-pot heating system comprises an inner shell, an outer shell surrounding the inner shell to form a duct between the two shells for preheating combustion air flowing down the duct to enter a combustion chamber within the inner shell. A container or pot for heating material such as water or foodstuffs may be supported inside the inner shell and above a combustion zone, such pot to be of diameter to form with the inner shell an annular flue for escape of combustion products. Draft control means are provided to regulate the amount of combustion air entering the combustion chamber.

Abstract: A heating chamber is defined by canted side walls in inverse pyramidal configuration, the base of the pyramid being open for admission of sunlight and the tip of the pyramid being truncated by a bottom plane. The chamber is adapted to positioning with the aperture plane generally normal to the rays of sunlight so that the canted walls may be fully and simultaneously exposed to sunlight. The inner wall surfaces are dull-blackened to enhance conversion of shortwave solar energy to long-wave or infrared energy whereby the walls are heated so as to radiate infrared (heat) energy for transfer of such heat energy to objects or materials which may be positioned within the heating chamber. The chamber aperture is closed by translucent material such as glass for enhancing the heating effect of the black interior wall surfaces. The aperture closure may rest freely over the aperture or may be hinged along one edge for convenience of opening for access to the interior of the chamber.