IMPROVEMENTS IN FURNACES
Year: 1857

page_text: LETTERS PATENT to Richard Archibald Brooman, of 166, Fleet Street,
in the City of London, E.C., Patent Agent; for the Invention of
"IMPROVEMENTS IN FURNACES." -A communication from F. H. Morel.
PROVISIONAL SPECIFICATION left by the said Richard Archibald
Brooman at the Office of the Commissioners of Patents, with his
Petition, on the 9th June 1857.
I, RICHARD ARCHIBALD BROOMAN, of 166, Fleet Street, in the City of
London, E.C., Patent Agent, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN FURNACES," (communicated to me by F. H.. Morel,
a foreigner) residing abroad,) to be as follows:
This Invention consists in setting the furnace bars in a frame, the back of.
which supports thei bridge, and in mounting the frame: upon trunnions, upon
which it may be made to oscillate.. The fore. end of the frame is connected. by'
a lever to a swinging. door,, which, when closed, shuts the entrance to the
ash-pit. The working of the furnace is as follows: After the fire has been
lighted, and when about to put on or immediately after putting on a fresh
charge of fuel, the fore end of the frame and bars is depressed by means of a
5 lever or other suitable arrangement worked outside the furnace; the bridge.
will be consequently raised;, and touching the roof of the furnace,, prevents the:

page_text: passage of any products of combustion over it. The lever connected with
the swinging ash-pit door also closes the entrance to the ash-pit, consequently
the only entrance for air is between the bottom of the furnace door and
the top of the fore, end of the inclined frame and bars. The position of
the bars admits of the fuel being spread evenly and regularly distributed
thereon, and the smoke and products of combustion passing over and through
the incandescent fuel on the back of the bars, in their passage through the back
of the bars, and under the bridge, become consumed. In a short time after
coaling, the frame, bars, and bridge may be restored to their horizontal
position.
Instead of the frame being free to oscillate upon trunnions it may be hinged,
or so fitted at front as to allow of the back being raised by means of a lever
and connecting rod, and in such case the only admission for air would be
through the furnace door; or a second bridge or moveable plate may be
placed behind the ordinary bridge, and being connected to a lever, may be
raised or lowered, so as to permit of passage to the flues over or under it, as
may be desired.
In all cases the opening to the ash-pit should be wholly or partially closed
while or immediately after coaling, and the smoke and other products of com-
bustion being caused to pass over, the incandescent fuel at the rear of the bars
and under the bridge become consumed, or as far so as may be.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Richard Archibald Brooman in the Great Seal Patent
Office on the 9th December 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD.2
ARCHIBALD BROOMAN, of 166, Fleet Street, in the City of London, E.C., Patent.
Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of June, in the year of our Lord One.
thousand eight hundred and fifty-seven, in the twentieth year of Her reign, :3
did, for Herself, Her heirs and successors, give and grant unto me, the said
Richard Archibald Broomán, Her special licence that I, the said Richard
Archibald Brooman, my executors, administrators, and assigns, or such others
as I, the said Richard Archibald Brooman, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to time and 3

page_text: at all times thereafter during the term therein expressed, should and lawfully.
might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention
for "IMPROVEMENTS IN FURNACES," communicated to me by F. H. Morel,
a foreigner residing abroad, upon the condition (amongst others) that I,
the said Richard Archibald Brooman, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause the same to
be filed in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
1
NOW KNOW YE, that I, the said Richard Archibald Brooman, do
hereby declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained in and
by the following statement thereof, reference being had to the Drawings
hereunto annexed, that is to say:-
:
This Invention consists in setting the furnace bars in a frame, the back of
which supports the bridge, and in mounting the frame upon trunnions, upon
which it may be made to oscillate. The fore end of the frame is connected by
a lever to a swinging door, which, when closed, shuts the entrance to the
ash-pit. The working of the furnace is as follows:-After the fire has been
lighted, and when about to put on or immediately after putting on a fresh
charge of fuel, the fore end of the frame and bars is depressed by means of a
a lever or other suitable arrangement worked outside the furnace, the bridge
will be consequently raised, and touching the roof of the furnace, prevents the
passage of any products of combustion over it. The lever connected with the
swinging ash-pit door also closes the entrance to the ash-pit,. consequently the
only entrance for air is between the bottom of the furnace door and the top of
the fore end of the inclined frame and bars. The position of the bars admits
of the fuel being spread evenly and regularly distributed thereon, and the
smoke and gases evolved from the fuel passing over and through the in-
candescent fuel on the back of the bars, in their passage through the back of
the bars and under the bridge, become consumed. In a short time after
coaling, the frame, bars, and bridge may be restored to their horizontal
position.
:
Instead of the frame being free to oscillate upon trunnions it may be
hinged, or so fitted at front as to allow of the back being raised by means of a
lever and connecting rod, and in such case the only admission for air would

page_text: be through the furnace door; or a second bridge or moveable plate may be
placed behind the ordinary bridge, and being connected to a lever, may be
raised or lowered so as to permit of passage to the flues over or under it, as
.may be. desired:
In all cases the opening to the ash-pit should be wholly or partially closed
while or immediately after coaling, and the smoke and other products of
.combustion being caused to pass over and through the incandescent:fuel at
..the rear of the bars and under the bridge, become.consumed, or as far so as
<may.be.
Figure 1 of the Drawings bereunto annexed is a front elevation of a steam
boiler furnace constructed according to one method of carrying out this.Inven-
tion; Figure 2 is a vertical longitudinal section; Figure 3 is a plan partly in
section through the linea, y, z, of Figure 1; Figure 4 is a plan of the frame
which supports the grate; and Figure 5 is a longitudinal section of the same
through the line. A, B, of Figure 4; Figure 6 is a view of the back part of
the furnace, which forms the moveable bridge; and Figure 7 is a view of a
partition between the two boilers above the moveable bridge. The same
Jetters refer to similar parts in all the Figures.
The grate of the furnace is composed of bars supported by a cast-iron
rectangular frame A, B, C, D, seen at Figure 4; this frame may be formed
in several pieces rivetted or otherwise connected together. To the frontiof the
frame a plate F is fitted or fixed in any suitable manner, and to the back part
of the frame a kind of trough D, D, D", is attached or made in a piece with
the frame, as seen in Figures 2, 4, and 5. This trough is faced with brick-
work or other like suitable substance, and forms the moveable bridge, the
shape of which is represented by the dotted lines a, b, c, d, e, f, Figure 1, and
also in Figure 6. The fire bars rest at one end on the edge of the plate F,
and at the other end on the bottom of the trough D. In or about the middle,
and under part of the side pieces C, D³, a groove G is formed, which fits or is
pivotted on supports or trunnions 'H, placed in the ash-pit. These trunnions
support the frame and the parts connected to it. P, R, is a lever attached to
the plate F. This lever extends to the exterior of the furnace, and is the
medium through which the grate is caused to oscillate on the trunnions H.
¡M is a door or plate, fitted to the lower part of the ash-pit in such manner as
to leave only a small space between its upper edge and the lower edge of the
plate F. If the grate remains horizontal or nearly so, as shewn in Figure 2,
the gases evolved from the fuel will pass off as in all ordinary furnaces, the air
ientering from beneath the grate through the opening in the ash-pit, and the

page_text: smoke and gaseous products pass off into the flues above the bridge by the
opening 1, m. When the grate is in the position just mentioned and the fire
is fed, dark combustible gases are evolved, and it is the burning of these gases,
which the Inventor proposes to accomplish in the following manner, in order
to avoid as far as possible the production of smoke :-Instead of opening the
ordinary door Sof the furnace, the end A, B, of the frame A, B, C, D, is
depressed by means of the lever P, R, or by any other suitable contrivance.
The grate is thus caused to oscillate on the trunnions H, and to assume, with
all the other parts connected to it, the position indicated by the dotted lines,
Figure 2. The plate F now rests on the plate M, in front of the ash-pit;
the ash-pit thus becomes. almost wholly closed. (In some cases, however,
it is necessary to admit a small quantity of air into the ash-pit to render
the combustion perfect.)--By the movement just described, an opening g, h,
is formed between the plate F and the door S, by which the furnace is
fed, and the bridge is made to assume the position shown in dotted lines at E',
thus closing the passage 7, m, and opening another n, p, below. The masonry
or brickwork if the furnace is made narrower at the part marked T, Figure 3;
so that the partition U, V, U, V, Figure 1, of the furnace shall be completed
through the whole of the breadth at the bridge. The result is that air enters
above the grate and passes through the fuel on the bars into the flues below
the bridge by the passage n, p. If when in this position a supply of fuel be
introduced to feed the fire, and equally spread over the whole of the grate, the
gases evolved will pass through the incandescent fuel on the grate, and be as
uearly as may be consumed before entering the flues of the furnace. The
combustion of these volatile materials always produces smoke in ordinarily
constructed furnaces, but in furnaces constructed on this principle they will be
burnt, and their combustion rendered perfect. By admitting a small quantity
of air below the grate at the junction of the plate F and the plate M, the
combustion may in some cases be improved. The stoker has in furnaces con-
structed as before described every facility afforded him for seeing the fire, and
this enables him to distribute the charges in layers of uniform thickness over
the whole surface of the grate.
The essential features of the improvements just described may be easily and
economically applied to existing furnaces.
And having now described the nature of the said Invention, and in what
manner the same may be performed, I declare that I claim,―
First, the improvements in furnaces herein-before described, and represented
in the Drawings hereunto annexed.

page_text: Second, the employment in furnaces of moveable bars and a moveable
bridge, so combined and worked that when fresh fuel is supplied to the
furnace the gases evolved therefrom shall be made to pass through the in-
candescent fuel on the bars; but when the burning of the fresh fuel has
proceeded for a suitable time, the gases evolved.therefrom shall be allowed to
pass over the said incandescent fuel and enter the flues without passing
between the bars; as herein-before described.
In witness whereof, I, the said Richard Archibald Brooman, have here-
unto set my hand and seal, this Ninth day of December, One
thousand eight hundred and fifty-seven.