GB411007A - Improvements in or relating to furnaces - Google Patents

Abstract

411,007. Boiler &c. furnaces. HERENG, A. J. A., 12, Rue Charles Nodier, Paris. Sept. 27, 1933, No. 26614. [A Specification was laid open to inspection under Sect. 91 of the Acts, March 28, 1934.] [Class 51 (i).] Grates ; ashpits.-A solidfuel furnace, adapted particularly for central-heating boilers, has a rotary grate 6 to which fuel is fed centrally in an upward direction by a worm 14 and which carries, on its periphery, scrapers 9 serving to convey ashes to an outlet in the base of an annular ashpan 8 concentric with the grate. The fuel is distributed by a fixed member 16, 17 which may be cooled by air passing therethrough to the fuel bed 22. The grate may be composed of ring-shaped bars 6, arranged to form either a flat or conical grate as shown in Figs. 2, 3 respectively, or radial bars 32, of the form shown in Fig. 6, may be employed. The grate is rotated intermittently from the worm shaft 14 through a mutilated pinion 12 which engages a toothed ring 11 secured to the members 7 supporting the grate bars. A fixed scraper may project through the wall of the furnace to remove ashes from the periphery of the grate to the ashpan 8, which latter may be fitted with an annular perforated plate 8<1>, Fig. 3, on which combustion of any unburnt particles is completed, the resulting ash being removed by upper extensions of the scrapers 9. Fig. 7 shows the grate structure disposed in a refractory-walled chamber 21 connected to the ordinary combustion chamber 30 of a boiler, the driving mechanism 28 for the grate and the air supply fan 29 being arranged in a gas-tight casing 25. To permit the speed of operation to be varied, the driving mechanism may comprise two electric motors designed to run at different speeds and switched in and out by a thermostat, or a variable-speed motor controlled by a thermostat may be employed.