Patent GB-174698-A (GB)
Title: Improvements in or relating to furnace grates
IPC: F23H11/00
Filed: 1920-10-25
Abstract: 174,698. Stowe, L. R. Oct. 25, 1920. Fire-bars and grates.-An inclined furnace grate is composed of a series of travelling chains arranged alternately with a series of stationarv firebars at the lower ends of which are provided rocking bars and comprises inter alia means for regulating the relative air supply to different parts of the grate. Figs. 4 and 5 show the upper and lower portions of the grate respectively. The stationary bars are formed in sections 85<a>, 85<b>, 85<c>, &c., the upper section beneath the fuel hopper being imperforate and the lower sections being in the form of grids with transverse webs spaced apart to form air passages which decrease in size towards the rear of the grate. The fire-box sections are mounted on supports 86<a>, 86<b>, &c. which are secured by bolts to transverse beams 87 supported on the side and intermediate longitudinal frames of the grate. Lugs 93 are provided on the central longitudinal webs of the supports with which hooks 125 on the fire-bar sections engage to secure them in position. The lower fire-bar sections and their supports are curved upwardly towards the rear. The travelling chains 50 pass over rear idle sprocket-wheels 49 mounted on the shaft 48 and driving sprocket-wheels 51 mounted on the shaft 52 mounted in bearings which may be adjusted for varying the tension of the chains. Each .chain comprises, as shown in Figs. 22 and 24, two inner and two outer series of links connected by pivot pins 81 and provided with side ribs to form air passages 82, the adjacent surfaces of the two inner-rows of links being cut away to engage the sprocket-wheels. The chains are supported on the sides 89 of the stationary fire-bar supports. The passage of air through the links of the chains is regulated by detachable shutters 131 which are provided with hooks 134 to engage with lugs 133 on the sides 89 of the fire-bar supports. The shutters are spaced apart to permit the passage of air, the supply of which may be varied by omitting some of the shutters or by interchanging them with others of different length. The stationary fire-bars are provided with grooves 115 for the accumulation of ash. The rocking bars 140 are hollow and provided with openings 151, 152 for the admission of air which is supplied to the fuel through openings 149. The rocking bars are arranged in groups and detachably mounted upon supports 165 secured to shafts 173 which are rocked by arms 175 provided on one of the supports of each group of rocking bars. The arms 175 are connected by rods 178 passing through tubular guiding and sealing-members 179 and tubular guides 181 to connecting-rods attached to levers 184 actuated by eccentrics mounted on a shaft 77. By altering the position of the pins 187 on which the levers 184 are mounted the degree of movement of the rocking bars may be varied. The return run of each travelling chain passes through sealing- casings 220 mounted on the rear wall 235 of the ash-pit. The casings 220 are formed by castings of the form shown in Fig. 41 arranged side by side, as shown in Fig. 38, to form passages 233 for the chains which are guided by removable plates 245, 246 secured to the lower and upper portions of the castings. The lower plates 245 are provided with springs 254 and the casings 220 are provided with corresponding openings 226 to permit the passage of compressed air, which may leak through the casings to the chamber 40 communicating with the atmosphere.