CERTAIN IMPROVEMENTS IN FURNACES FOR STEAM BOILERS AND OTHER PURPOSES
Year: 1869

page_text: LETTERS PATENT to John Hauworth, Manager, and Henry Horsfall,
Draughtsman, both in the Employ of Messieurs Fielden Brothers,
of Todmorden, in the County of Lancaster, for the Invention of
"CERTAIN IMPROVEMENTS IN FURNACES FOR STEAM BOILERS AND OTHER
PURPOSES."
Sealed the 12th November 1869, and dated the 31st May 1869.
PROVISIONAL SPECIFICATION left by the said John Hauworth and
Henry Horsfall at the Office of the Commissioners of Patents,
with their Petition, on the 31st May 1869.
We, JOHN HAUWORTH, Manager, and HENRY HORSFALL, Draughts-
man, both in the Employ of Messieurs Fieldén Brothers, of Todmorden,
in the County of Lancaster, do hereby declare the nature of the said
Invention for "CERTAIN IMPROVEMENTS IN FURNACES FOR STEAM BOILERS AND
OTHER PURPOSES," to be as follows:-
Our Invention consists in certain improved combinations of parts
forming a furnace, which is particularly applicable to the flues of steam
boilers, but which may be applied for various other purposes, the object

page_text: and effect of our Invention being to economisc fuel and to consume
smoke..
In performing our Invention we make use of a set of stationary
tubular grate bars connected to the front of the boiler and to a water
pocket near the bridge, which is in communication with the lower part
of the boiler to ensure a free circulation of water through the said
tubular grate bars; we also employ in combination therewith one or
more sets of solid grate bars placed in front of the tubular grate bars,
and a sliding plate, to both or all of which to-and-fro motions are given.
The sliding plate works under the hopper and carries the coal from the
hopper to the sets of solid grate bars, which in like manner deliver it to
the tubular grate bars. The coal on the tubular grate bars is carried
forward towards the bridge by a set of narrow toothed rakes, which are
moved up and down and to and fro between the tubular grate bars by
cranks or other equivalents, actuated by elliptical wheels, whereby the
rakes are raised and carried forward rapidly to prevent them being
burnt; these rakes not only carry the coal and clinkers forward but
they keep the fire clear. We apply a fire-brick arch between the end
of the boiler and the hopper to promote the combustion of the coal,
and a sliding door to regulate the feed in the ordinary manner. The
requisite to-and-fro motion is given to the sliding plate and solid grate
bars by cranks or other equivalents.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Hauworth and Henry Horsfall in the Great
Seal Patent Office on the 29th November 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, wc, JOHN
HAUWORTH, Manager, and HENRY HORSFALL, Draughtsman, both in
the Employ of Messieurs Fielden Brothers, of Todmorden, in the County
of Lancaster, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirty-first day of May, in the year of
our Lord One thousand eight hundred and sixty-nine, in the thirty-.
third year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said John Hauworth and Henry Horsfall, Her
special licence that we, the said John Hauworth and Henry Horsfall,

page_text: our executors, administrators, and assigns, or such others as we, the
said John Hauworth and Henry Horsfall, our 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 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 "CERTAIN IMPROVEMENTS IN FURNACES FOR
STEAM BOILERS AND OTHER PURPOSES," upon the condition (amongst others)
that we, the said John Hauworth and Henry Horsfall, our executors
or administrators, by an instrument in writing under our, or their, or
one of our or 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
. Scal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that we, the said John Hauworth and Henry Horsfall,
do hereby declare the nature of our said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-.
tained in and by the following statement (that is to say) :-
Our Invention consists in certain improved combinations of parts
forming a furnace, which is particularly applicable to the flues of steam
boilers, but which may be applied for various other purposes, the object
and effect of our Invention being to economise fuel and to consume
smoke.
In performing our Invention we make use of a set of stationary
tubular grate bars connected to a chamber at the front of the boiler and
to a water pocket near the bridge, which is in communication with the
lower part of the boiler to ensure a free circulation of water through the
said tubular grate bars; we also employ in combination therewith one or
more sets of solid grate bars placed in front of the tubular grate bars
and a sliding plate, to both or all of which to-and-fro motions are given.
The sliding plate works under the hopper, and carries the coal from the
hopper to the sets of solid grate bars, which in like manuer deliver it to
the tubular grate bars. The coal on the tubular grate bars is carried
5 forward towards the bridge by a set of narrow toothed rakes, which are
moved up and down and to and fro between the tubular grate bars by
cranks or other equivalents actuated by elliptical wheels, whereby the
rakes are raised and carried forward rapidly to prevent them being

page_text: burnt; these rakes not only carry the coal and clinkers forward, but they
keep the fire clear. We apply a fire-brick arch between the end of the
boiler and the hopper to promote the combustion of the coal, and a
sliding door to regulate the feed in the ordinary manner. The requisite
to-and-fro motion is given to the sliding plate and solid grate bars by
cranks or other equivalents.
And in order that our Invention may be fully understood and readily
carried into operation, we will proceed to describe the two accompanying
Sheets of Drawings, reference being had to the figures and letters marked
thereon.
On Sheet 1 Figure 1 is an end elevation, partly in section, of a steam
boiler with a single flue to which our improved furnace is applied. We
wish to remark here that our improved furnaces are applicable to two-
flued and other boilers, and to other purposes. Figure 2 is a side
elevation of our improved furnace and part of the boiler; Figure 3 is a
plan of the same, half of which is shewn with the upper part of the
furnace removed to shew the interior.
On Sheet 2 Figure 4 is a side elevation, in section. a is the outer
shell of the boiler, and the flue. To the front plate of the boiler are
secured the side plates c, in which are cast or fixed the various bearings
for the driving and other shafts, as will be described hereafter.
The grate of our improved furnace consists of three parts, namely, the
stationary tubular grate bars d, the movable grate e, and the movable
grate, which is cast or fixed to the sliding dead plate. The front
ends of the tubular grate bars are cast in the water chamber d', to the 2
ends of which the double elbow pipes are connected; these pipes
form the cominunication between the grate bars and the front of
the boiler. The back ends of the tubular grate bars are cast in the
water pocket g, the upper surface of which forms the bridge, and the
lower part of this water pocket is connected to the lower part of 3
the flue by the pipes g'. There are screws tapped into the front of
the chamber d', as shown in Figure 4, one screw being opposite the
end of each tubular grate bar d. When these screws are taken out
the tubular grate bars can be cleaned by passing a rod through them.
When the fire is kindled on the grate a constant current of water is kept 3
up from the lower part of the boiler through the pipes g', pocket g, grate
bars d, chamber d', and side pipes to the upper part of the boiler;
this current tends to equalize the temperature of the water in the boiler,

page_text: prevents the tubular grate bars & being injured by the heat, prevents
also the adhesion of clinkers to the grate bars, and utilizes the heat
absorbed by the grate bars. To the front of the water pocket g is hinged
the door g, which is opened once or twice a day, or whenever it may
5 be required, by the attendant for scraping out the clinkers, which are
carried, over the bridge, and fall into the fluc. Between the tubular
grate bars are a set of narrow toothed rakesh, which are shown best in
Figures 5 and 6; these rakes are mounted on rods connecting the
levers h', and an up-and-down and to-and-fro motion is imparted to
them, as will be described hereafter. The sides of the movable grate c
are supported on flanges cast on the plates c, as shewn to the right of
Figure 1, and the front end of this grate.moves to and fro over the water
chamber d. The front end of the movable grate f, which is also
supported on flanges cast to the plates c, moves to and fro over the
grate e, and the dead plate f' moves to and fro under the hopper formed
by the angle plate and the sliding door, which can be raised or
lowered to vary the depth of the feed by a cross shaft, and chains, as
shewn in the Drawings, or other equivalents. There is a fire-brick arch
between the sliding door j and the end of the boiler, and the bricks of
this arch enter a short distance into the fluc to protect the joint of the
flue to the front of the boiler. The grates e and fare moved slowly to
and fro in opposite directions in the following manner:-The vertical
shaft is driven by steam or other power, and a worm on this shaft
gears into the worm wheel m¹ on the shaft m, to which are also fixed the
elliptical wheels m for moving the toothed rakesh, and on the face of
these wheels are mounted antifriction bowls taking into the open
frames m³, which are supported by studs passing through slots in the
plates c, thereby moving them slowly to and fro. At the lower side of
each frame m³ is fixed a stud m, taking into a slot in the lower end of
the double levers m³, which are loose on the shaft m; the upper ends of
these levers take on to studs projecting from the movable grate e. The
grate fand dead plate fare moved to and fro in the contrary direction
to the grate e by the studs n taking in slots in projections cast to the
dead plate f, as shewn in Figure 4. The elliptical wheels m² above
referred to gear into similar wheels n' and o' fixed on opposite ends of
the crank shafts n and o, and the levers h, to which the toothed rakes h
are connected, are supported on these crank shafts, the motion of which
is alternately slow and quick; the quick motion is made to lift and
move forward the toothed rakes, and the slow motion is to lower and

page_text: bring them back, consequently the rakes are only a short timo in the
fire, and they have time to cool in going slowly back. The air for
promoting the combustion of the fuel enters between the grate bars of
the grates d, e, and, and through perforations in the ends of the grates c
and, as shewn in section in Figure 4. The grates e and and the
rakes may be worked by hand when required by the shaft.p, sec
Figure 3, and pinion p' gearing into the wheel on the shaft n.
The mode of operation is as follows:-The fresh fuel from the hopper
is carried forward by the dead plate and grate, and at the retrograde
motion of this grate a portion of the fuel, which is then partially ignited,
falls on to the grate e, which carries it forward and deposits it on the
water chamber d'; the fuel, which at this point is fully ignited, is pushed
on to the grated by the end plate of the grate e, and it is carried
gradually forward along the grate d by the toothed rakesh, by which
the unconsumed portions of the fuel and the clinkers are ultimately
thrown over the bridge formed by the water pocket g. By this arrange-
ment the attendant has only to keep the hopper properly filled with
fuel, and to remove the clinkers occasionally from the flue, and the fuel
is gradually carried from the hopper to the bridge by the self-acting
portions of the furnace. The inflammable gases from the fresh coal
having to pass over the bright fire on the grate d are consequently
consumed, thereby economising fuel and preventing smoke.
Figure 7 represents in section the form of tubular grate bar which wo
should prefer for the grate d; the top of these bars is flat, and the
corners are left as sharp as can be to prevent the cinders from being
caught by the toothed rakes when they are lowered into the space
between the grate bars. We wish to observe that the shape of the
tubular grate bars may be varied.
We have shewn our improved furnace with two sets of solid grate
bars and one set of tubular grate bars, it is however possible that in
some cases a single set of solid grate bars may be sufficient, and in other
cases it may be desirable to employ more than two sets.
Having thus stated the nature of our Invention, and described a
convenient mode of carrying the same into operation, we wish it to be
understood that we do not intend to limit ourselves to the details given,
nor to the mode of giving motion to the working parts of the furnace, as
the same may be considerably varied; we would also observe that we do

page_text: not intend to claim the sliding grates and tubular grate bars when used
separately; but what we claim is,—
First. The combination and arrangement of sliding grates and tubular
grate bars, as shewn and described.
And, secondly. The toothed rakes working between grate bars in the
manner and for the purposes described.
In witness whereof, we, the said John Hauworth and Henry
Horsfall, have hereto set our hands and seals, this Twenty-fifth
day of November One thousand eight hundred and sixty-nine.