GB421025A - Automatic solid fuel stokers - Google Patents

Abstract

421,025. Boiler furnaces; mechanical stokers. NAAMLOOZE VENNOOTSCHAP VERWARMINGS MAATSCHAPPIJ, 5, Westerstraat, Utrecht, Holland. March 23, 1934, No. 9173. Convention date, March 30, 1933. [Class 51 (i)] A solid fuel stoker device includes superimposed communicating chambers (as shown there are two chambers 4 and 8) with a reciprocable piston within each chamber and means for operating the pistons so that the upper piston 5 will move fuel from its chamber into the lower chamber 8 and the lower piston 10 will subsequently discharge the fuel into the furnace, the lower piston sealing the opening 9 between the two chambers during the propulsion of fuel into the furnace. Fuel is fed to the upper chamber from a bunker (not shown) by way of a hopper 3. The pistons are of unequal cross section, the upper piston being the smaller, and they are driven from a motor 20 through link mechanism so as to operate in alternate manner. The chamber 8 communicates with the combustion space 1 at the top of a water-cooled grate 2 which is provided at the rear end with a rotary slag breaking device comprising arms 14 operating between the ends of the grate bars. Slag is removed by a screw conveyer 12, the slag breaker and conveyer being driven from the motor 20 which may be thermostatically controlled. As shown the apparatus is in the form of a detachable unit mounted on balls or rollers and adapted to be coupled to an existing boiler. The combustion chamber is provided with a half-cylindrical water jacket 15, an air inlet 18, ash pit 19 and water cooled bridge 21. A modified form of stoker has a greater number of chambers and the pistons are operated so that each intermediate piston closes the communication between its chamber and one of the adjacent chambers while the communication with the other adjacent chamber is open to permit the passage of fuel.