Patent GB-191307416-A (GB)
Title: Improvements in Furnaces with Mechanical Stokers of the Under-feed Type.
Inventor: RATEL MAURICE
IPC: F23K3/12
Filed: 1913-03-28
Granted: 1914-01-01
Abstract: 7416. Ratel, M. March 28, 1912, [Convention date]. Mechanical stoking; grates; air supply, regulating.-In a furnace of the kind in which there are a number of inclined fuel troughs formed with blast tuyeres on each side, and to which fuel is fed by a mechanical stoker of the underfeed type, each fuel trough is fed by a series of superposed reciprocating pushers of variable stroke, and means are provided for controlling the operation of the pushers and the supply of air to the furnace simultaneously. As shown in Fig. 1, each main pusher 1 for feeding the fuel is actuated by a bell-crank lever 2 which produces an oscillating movement of the rod 3. This rod is connected by rods 5, 6, 7 to the pushers 8, 9, 10 which are given reciprocating movements of varying amplitude and are mounted on roller or ball bearings to reduce friction. The pushers are driven from a shaft 22, which is connected through a change-speed gear and a transmission device 20 with the main shaft 19. Motion is also transmitted from the shaft 19 through the device 23, bevel-wheels 24, 25, and shaft 26 to eccentrics, bell-crank levers, &c. for reciprocating the bars 13, 14, 15 arranged above the ash-shoot 17 and in front of a plate 16 for diverting the ashes into a hopper or other receptacle. The plate 16 mav be replaced by a tilting-plate. Fig. 8 shows the device for controlling the fuel supply to each trough and the air supply simultaneously. The change - speed gear in the box 49 is driven through a clutch 51 and wheel 50 from the main shaft 19. When it is desired to change speed, a sliding rod 57 at the back of the change-speed lever 55 is depressed bv a knob 56 so as to cause its lower end to operate the bellcrank lever 52, 53 and release the clutch 51.. At the same time, a projection on the rod 57, which engages with one or other of the teeth 58, is released and the change-speed lever may then be operated to vary the speed. Upon releasing the knob 56, a spring 54 causes engagement of the clutch. The lever 55 is connected by a cord or wire 59 to the counterweighted damper 60 controlling the admission of air to the furnace. Blast is supplied through a pipe 18 to a box 11 communicating with the tuyeres 12, which are of round, polygonal, triangular, or other form. The tuyeres are provided, as shown in Figs. 3 and 4, with internal partitions 31 for directing the air blast. The tuyeres may be provided externally with transverse ribs between which ashes may accumulate to form a protecting surface. Specification 28,475/04 is referred to. The Specification as open to inspection under Section 91 (3) (a) comprises also a modification in which the main pusher for each trough is connected by a rod to secondary pushers of decreasing size towards the rear, and a modification in which the troughs are horizontal and of decreasing height towards the sides of the furnace and of like or decreasing section. The quantity of fuel fed to each trough is varied by varying the stroke or section of the pushers. At the sides of the furnace, reciprocating bars and tilting grates are provided. This subjectmatter does not appear in the Specification as accepted.