IMPROVEMENTS IN THE CONSTRUCTION OF FURNACES FOR STEAM BOILERS AND OTHER PURPOSES
Year: 1874

page_text: LETTERS PATENT to John Aiken Salmon, of Manchester, in the
County of Lancaster, for the Invention of "IMPROVEMENTS IN THE
CONSTRUCTION OF FURNACES FOR STEAM BOILERS AND OTHER PURPOSES.”
Sealed the 3rd February 1875, and dated the 30th November 1874.
PROVISIONAL SPECIFICATION left by the said John Aiken Salmon at
the Office of the Commissioners of Patents, with his Petition, on the
30th November 1874.
I, JOHN AIKEN SALMON, of Manchester, in the County of Lancaster,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN THE CONSTRUCTION OF FURNACES FOR STEAM BOILERS AND OTHER PURPOSES,"
to be as follows:-
The Invention consists principally of the combination of a large air
aperture in the furnace door provided with baffle plates both inside and
outside the door, with a series of revolving fire-bars, and a coke chamber
or oven at the end of the bars.

page_text: The aperture in the fire-door is nearly half the depth of the door, and
is protected from without by a baffle plate sloping downwards and out-
wards therefrom, and inside the door is a second baffle plate projecting
downwards and inwards so as to direct the air down on to the fuel.
The revolving fire-bars are made in the form of shafts, having a series |
of discs or circular plates threaded thereon at intervals apart, the said
shafts lying longitudinally in the furnace (i. c. from the door to the
bridge) and resting on journals in a dead plate at front and back.
Between each revolving bar is a fixed bar, the side of which is notched
so as to fit the discs and to scrape and clear them from clinkers as they :
revolve. In some cases I propose to dispense with these fixed bars or
scrapers and to mount the revolving bars so that their discs interlock, in
which case they will scrape and clear cach other.
The revolving bars may either be arranged so as to be turned by hand
from time to time, or they may be suitably geared with the engine and
kept constantly revolving.
Behind the bars, and between them and the bridge, in some cases I
propose to form a coke chamber or receptacle with a bottom of fire-brick
or fire-clay, into which the fuel when coked is pushed forward, and the
smoke and gases from the fresh fuel in passing over this incandescent
mass become entirely consumed.
The bridge I prefer to make in a semicircular shape to follow the form
of the fluc, or an open bridge may be employed, and in some instances
I form a longitudinal central division in the coke chamber or re-
coptacle.
2
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Aiken Salmon in the Great Seal Patent
Office on the 28th May 1875.
"
'
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
AIKEN SALMON, of Manchester, in the County of Lancaster, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirtieth day of November, in the

page_text: year of our Lord One thousand eight hundred and seventy-four, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said John Aiken Salmon, Her
special license that I, the said John Aiken Salmon, my executors,
administrators, and assigns, or such others as I, the said John Aiken
Salmon, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
during the term thercin 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 THE CONSTRUCTION OF FURNACES FOR STEAM BOILERS AND OTHER
PURPOSES," upon the condition (amongst others) that I, the said John
Aiken Salmon, 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.
NOW KNOW YE, that I, the said John Aiken Salmon, 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 and accompanying Drawings (that is
to say) :-
This Invention consists principally of the combination of a large air
aperture in the furnace door provided with baffle plates both inside and
outside the door, with a series of revolving fire-bars, and a coke chamber
or oven at the end of the bars.
Such being the nature and object of my said Invention, I will now
proceed to describe in detail the manner in which the same is to be
or may be performed or carried into practical effect, and in order that the
same may be clearly understood I have annexed hereunto a Sheet of
Drawings illustrative thereof, and have marked the same with figures and
letters of reference corresponding with those in the following explanation
thereof:
In the annexed Drawing, Fig. 1 is a vertical longitudinal section of
the furnace of a steam boiler constructed according to my Invention ;
Fig. 2 is a vertical transverse section; and Fig. 3, a horizontal section
of the same.

page_text: Fig. 4 shows horizontal and transverse sections of a slight modification
thereof; and Figs. 5 and 6 show different forms of open bridge; and
Fig. 7 is a form of bridge to be used where there is a deficient draught.
a, a, is the shell of the boiler, and b, b, the flues.
In Fig. 1 the aperture c, c, in the fire-door; d, d, is nearly half the
depth of the door, and is protected from without by a baffle plate e, e,
sloping downwards and outwards therefrom, and inside the door is a
second baffle plate, projecting downwards and. inwards so as to direct
the air down on to the fuel.
The revolving fire-bars are made in the form of
squaro shafts I, I,
having a series of discs or circular plates h, h, threaded thereon at
intervals apart, the said shafts lying longitudinally in the furnace (i.e.
from the door to the bridge), and resting on journals in a dead plate at
front and back. I would here remark that if preferred these discs,
instead of being plain, as shown on the Drawing, may be notched at the
edges.
Between each revolving bar is a fixed bar i, i, the side of which is
provided with projections or scrapers k, k, (Fig. 2) which fit the discs.
h, h, and scrape and clear them from clinkers as they revolve. In some
cases I propose to dispenso with these fixed bars or scrapers and to
mount the revolving bars so that their discs interlock, as shown at Fig. 4,
in which case they will scrape and clear each other.
The revolving bars may either be arranged so as to be turned by hand
from time to time, or they may be suitably geared with the engine and
kept constantly revolving.
Behind the bars, and between them and the bridge, in some cases I
propose to form a coke chamber or receptacle with a bottom 1, 1, (Fig. 1)
of fire-brick or fire-clay, into which the fucl when coked is pushed
forward, and the smoke and gases from the fresh fuel in passing over
this incandescent mass become entirely consumed.
The bridge m, m, I prefer to make in a semicircular shape to follow
the form of the flue (see Fig. 2), or an open bridge (sce m', m³, Figs. 1, 5,
and 6) may be employed, and in some instances I form a longitudinal
central division in the coke chamber or receptacle, as shown by the
dotted lines n, n, in Fig. 3.

page_text: Having now described the nature and object of my said Invention,
together with the manner in which the same is to be or may be per-
formed, I wish it to be understood that I claim as my Invention,―
Firstly. The combination of a large aperture in the furnace doors with
baffle plates inside and outside the same.
Secondly. The revolving disc fire-bars, constructed and mounted sub-
stantially as herein-before described.
And, Thirdly. The coke oven or chamber at the end of the bars
between them and the bridge.
In witness whereof, I, the said John Aiken Salmon, have hereunto-
set my hand and seal, this Twenty-seventh day of May, in the
year of our Lord One thousand eight hundred and seventy-
five.
Witnessed by
JOHN HUGHES,
Clerk to George Davies, C.E.,
Patent Office,
St. Ann's Sq.,
Manchester.
JOHN A. SALMON. (L.S.)