15,458. Kitchen, J. M. W., and Bernuth, O. von. July 4. Steam-generator furnaces ; pulverulent and small fuel fittings ; mechanical stoking ; grates ; ashes, collecting and removing. - Consists of a furnace plant capable of burning low-grade fuel for generating steam or for making producer or water gas for use in internal-combustion engines or elsewhere. Each unit, of which there are preferably two arranged back to back, comprises a specially-formed grate surmounted by a high combustion chamber with adjacent heating-chambers through one of which the gases pass on their way to the chimney or other outlet, together with fuel-feed devices and means for supplying air both above and below the grate. The apparatus comprises in addition, airsupply heating-devices, water-distilling and condensing apparatus, sectional steam generators, steam superheaters, ash-dischargers, and means for the independent or simultaneous control of the various auxiliary motors. Figs. 1 and 2 show sections at right-angles. Soft coal, which is supplied by shoots to hoppers Q, is fed therefrom to two chain grates G, which deliver it, partly coked, to a central grate G<1> at a lower level. Coal dust is delivered by shoots J<4>, with the help if necessary of hot gases injected into the shoots, on to fire-brick arches W<3> at the sides of the combustion chamber and above the grates G, and hot air by tuyeres W<2> just below. Producer &c. gas is formed owing to the passage of air or steam through the relatively deep bed of fuel on the grate G<1> and, if the upper air supply be stopped, can be drawn off for use as required. In any case, the gases pass from the combustion chamber through openings 0 near the top, into a heating-chamber H at the front and flow downwards therethrough to dampers controlling- the passage to the chimney &c. The bottoms of the heating-chamber H and of similar chambers at the sides of the combustion chamber are sufficiently high to allow of access to the lower parts of the combustion chamber walls. The bottom of the heating-chamber is formed of non-conducting, metallic-framed slabs hinged to open readily for cleaning. The piston-valves F<1> controlling the outlet to the flue can likewise be readily removed for cleaning purposes. The grates G, Fig. 4. are mounted on two-part frames B. The chain links are curved to the radius of the sprocket-wheels so as to run in close contact with the walls C<5> of the central grate and thus cause the complete removal of the fuel. The bars of the lower grate G<1> are oscillated by apparatus shown in Fig. 9. Arms on the grate bars are coupled to a bar, which is moved one way or the other alternately by means of an hydraulic cross-head Y' and jerked back to the central position by springs S<2>. The back of each hopper Q, from which the upper gates G are supplied, is hinged at the top and formed with a hinged lower portion. The back can thus be moved by means of a cam to regulate the discharge from the hopper. Forced draught is supplied by a fan Z, and is supplied above the grate through brickcased tuyÞres W<2> and also immediately below the central grate G'. The tuyÞres W<2> communicate with a distributing-box through valve-controlled pipes A<4>, Fig. 4. Induced draught is produced wholly or in part by a fan N<1> driven by a turbine N<2>, Fig. 1. The various auxiliary hydraulic motors for the grates, fans, &c. are operated by a supply having no connexion with the furnace and can thus be driven quite independently of the state of the fires &c. Impure water is heated by exhaust steam in a tank P having partitions P' decreasing in height towards the outlet end. The steam thus produced is forced by a pump D<3> through a condenser R in which the heating of the forced draught is in part effected. The water from the condenser R is forced by a pump D into the air heater X. The pressure water for operating the auxiliary motors and feed-water for the boilers is pumped by means of the independent plant shown in Fig. 2. This plant comprises a gas-producer C', an internalcombustion engine C<2> and water pump M, and an internal - combustion engine and compressor M<3>. Water is pumped to an elevated tank M', from which it is supplied to the various auxiliary motors. Waste steam from the jackets of the combustion engines, or from other sources, is forced by the compressor M<3> through the superheaters B<2>, and may be mixed with the steam from the generators. Exhaust from the combustion engines is introduced into an economizer C<3> at levels corresponding to the temperature of the material to be heated. The ashes are received onanashdischarger, Figs. 10 and 11, consisting of a number of centrally pivoted, normally horizontal slats linked to each other and fitted with a deep upstanding rib G<3>. Thus on tilting the slats, only the lower layer of ashes is discharged. Passages below the level of the grates allow of the introduction of ash-trucks. The air for induced draught is heated by passing in succession through chambers at the side of each combustion chamber on its way to the ash-pit. The air for forced draught is heated by being drawn by the fan Z through a water cooler X and then forced through a condenser R. In the heating-chamber H are the tubes T of a water-tube boiler, connected in sections to upper drums B which are situated at the top of the combustion chamber. Feed-water is supplied from a tube T<2> to the lower ends of the sections, and circulation pipes T<5>, T<6> connect the drums with the outer ends of the upper headers. The sections are supported partly by the pipe T<6> and partly by chains. A steam superheater B<2>, Fig. 2, is situated in one of the chambers at the side of the combustion chamber, and is heated by hot gases drawn through the chamber by a fan.