Patent GB-189820561-A (GB)
Title: Improvements in Furnaces for Steam Generators.
Inventor: TUCKER BENJAMIN WHITEHEAD
Filed: 1898-09-29
Granted: 1899-07-29
Abstract: 20,561. Tucker, B. W. Sept. 29. Firebars and grates; mechanical stoking.- Relates to revolving conical grates with oscillating segments for steam-boiler furnaces, and to fuelfeeding apparatus for use with the same. A circular frame composed of two rings F, I, united by the sections a, is mounted on a circular ballbearing base, the balls being arranged in two annular grooves made in the bottom of the frame, as shown in Fig. 3, and running on the inclined upper surfaces of the ring L, the latter being thus constructed to prevent the choking of the bearing by ashes. The frame is rotated by the pinion H on the shaft J<1> driven by suitable gearing from the shaft n. Supported on the frame and travelling with it is a circular grate composed of radial sectors 0, the latter being inclined towards the centre of the frame, as shown in Fig. 1, in which two only of the sectors are shown. The sectors constitute the grate bars, one being shown in detail in Figs. 6 and 8, in which R, R are two rigid side bars, provided with teeth, fixed together at the upper ends by the plate X and further connected by short shafts passing through the apertures W. Mounted on these shafts are a number of toothed segments S, one of which is shown separately in Fig. 11, provided with lugs b by means of which they are secured to the bars d. The bars d are provided with lugs e, which, as the grate rotates, are acted on alternately by the arm f and flange g, thus reciprocating the bars and oscillating the segments S. This rocking of the segments breaks up the bed of fuel resting upon them, so preventing clinkering. Fuel is automatically fed on to the grate from the hopper P by means of the shovel Q. A blade G is provided in order to break down the bridge of fuel tending to form at the outer portions of the sectors. The shovel and blade are both worked from the power shaft n, on which is placed an adjustable eccentric y which works the shovel by means of a fork z, levers p, and links w, the fork and levers being mounted on the shaft o. The blade G is similarly oscillated by means of a cam E', also mounted on the shaft n. Centrally within the rotating frame is a cylindrical grate i, above it being a ring h fixed to the frame and supporting the lower ends of the sectors, while below it is the ashpit C, from which the ashes are removed by the conveyer D, the latter being driven from the shaft J<1> by the sprocket-wheels L' and chain M'. Arrangements are made for varying the motion of the movable parts ; the position of the arm f can be altered, thus changing the throw of the bar d and the attached segments S. The eccentric y shown in detail in Figs. 9 and 10 is furnished with a pin e<1> which fits in the holes formed in the flange c<1> of the eccentric hub, thus enabling the throw of the eccentric to be varied and correspondingly altering the motion imparted to the fork z, Fig. 1, and the rate of stoking. By means of a clutch on the shaft n, the gearing connecting the shafts n and J<1> can be thrown out of gear, thus bringing the rotating frame and other parts operated by the shaft J' to rest.