FURNACE Russian patent published in 2008 - IPC F24B7/00 

FIELD: the proposed invention refers to heating arrangements particularly to metallic flame furnaces on solid, liquid or gaseous fuel assigned for air or water heating of living or non-living spaces, for example of buildings including country houses, saunas, garages, shops, hangars, sheds, hothouses etc.

SUBSTANCE: the furnace consists of a fire-box with a fuel hatch, a fire bar placed between the fire-box and the ash pit, an ash pit, a chimney, an external smoke-duct channel for discharge of hot smoke gases from the fire-box to the chimney which is located above the fire-box. The ash pit has a movable regulated shutter, The smoke-duct channel is connected with the fire box with the aid of a branch pipe located in the rear part of the fire-box and fulfilled with many turns, its section has the shape of a quadrangle, the height of the section of the smoke-duct channel in 2-20 times prevails its width and the volume is 0,1-1,5 of the volume of the fire-box. The smoke-duct channel forms a basket-type receptacle with three walls, open from the upper and from one side, the input of the smoke-duct channel is located on the opposite side from the fuel hatch and between the fire-box and the smoke-duct channel there are slits from three sides for feeding air.

EFFECT: provides comfort and simplicity of operation at flexible regulation of heat emission.

4 cl, 1 tbl, 5 ex