Improvements in Furnaces and Grates therefor and Means for Conducting Air thereto.
Year: 1890

page_text: Date of Application, 7th Jan., 1890
Complete Specification Left, 14th Mar., 1890-Accepted, 10th May, 1890
PROVISIONAL SPECIFICATION.
Improvements in Furnaces and Grates therefor and Means for
Conducting Air thereto.
1, SAMUEL JEWETT MILES of 1007 Opera House Block, Chicago, Illinois, United
States of America, do hereby declare the nature of said invention for IMPROVEMENTS
IN FURNACES AND GRATES THEREFOR AND MEANS FOR CONDUCTING AIR THERETO
as follows:-
The furnace and appliances are designed especially for burning fine fuel as for
instance hard coal slack. The grate bars are hollow or they are perforated, preferably
with slots, and supplied with air under blast, which is forced up through such perfora-
tions or slots to aid combustion. If this air is conducted by pipes directly to the
hollow grate bars then such pipes should be inclined to a central drum so that the
particles falling in may be extricated from such drum; and if the air is furnished by
pipes discharging toward the grate bars, the latter being simply perforated plates, then
the chamber or chambers in which such pipes lie should be air tight or capable of
being made so and should preferably have inclined sides so that the particles may be
gathered and removed; and if the hollow grate bars are employed then they should
be provided with slides and apertures so as to permit of their being cleaned; and
pipes and grate bars and grates in suitable manner.
Dated this 7th day of January 1890.
FREDERIC PRINCE,
Agent for Applicant.
COMPLETE SPECIFICATION.
Improvements in Furnaces and Grates therefor and Means for
Conducting Air thereto.
I, SAMUEL JEWETT MILES of 222 Market Street, Chicago, Illinois, United States
of America, Engineer, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement:―
My invention is illustrated in the accompanying drawing, Figure 1 being a cross
section and Figure 2 a longitudinal section.
A is the casing, B the boiler, F. G depending curtain walls, D. E bridge walls
X and Y rear grate bars, K and L successive combustion chambers, X' and Y' air
pipes leading to and opening through the grate bars X and Y and connected respec-
tively with the air blast pipes X and Y which lead to the blast pipe N' from the
fan N. N is another air pipe leading to this fan which might be connected to the
pipes Y if preferred. N³ is a third pipe leading to the fan and opening into
the chambers M M, or pipe N³ could open into one of these chambers, and N2 into
another. From these pipes lead the vertical pipes T T¹ into the transverse pipes T T,
one at each end of the fire box. These pipes are connected by the longitudinal
upwardly perforated pipes T2 T2. Resting upon the ledges 0 O and R R are the
longitudiually slotted sectional grate bars having the slots S S and portions P P as
shown. U U are the longitudinal curtains which divide the chambers beneath the
grate bars into sections to each of which sections passes one of the pipes T. Below
these walls the inclined sides V V form a chamber which terminates below in the
perforated bottom having the slide V₁, which is also perforated within the chamber.
Beneath these slides is the conveyer W with the crank handle W₁. H is the door
through which the fuel is supplied.
A quantity of fuel having been supplied through the door H, the same being any

page_text: kind of fuel whether fine, powdered coal or coal slack or refuse, and the fan being
started, a current of air will be discharged from the perforated pipes T2 T2 into the
comparatively air tight chambers surrounding them, and will pass upward through the
slots in the grate bars above, thus securing a free, wide spread.and evenly distributed
combustion of the fuel in the fire box of the furnace. Evidently the draft, being
something more than normal, will tend to carry over a certain quantity of fuel
unconsumed, and such fuel is deflected at the curtain wall F upon the grate,X where
it is again treated to a blast of air and given opportunity to burn. In like manner
the remaining refuse is burned in the next successive combustion chamber. The con-
struction of the bars, and the arrangement of parts and the means for cleaning the
apparatus back of the first bridge wall is not specifically dwelt upon, the debris falling
from the grate bars into the fire box is thrown upon the perforated bottom and by
moving the slide thereon would be discharged into the conveyer box below, whence it
is easily removed by the worm W.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is;
1. A practically air tight ash pit, or ash pits, with perforated grate bars above
and blast pipes discharging into such ash pits below, with means for cleaning the
same.
2. A succession of combustion chambers with bridge walls and curtain walls,
grate bars and air supplying pipes connected with one or more of such combustion
chambers.
Dated this 11th or of March 1900
FREDERIC PRINCE,
1, Quality Court, Chancery Lane, London, Agent for Applicant.