Improvements relating to the Combustion of Fuel in Domestic and other Fireplaces.
Year: 1893

page_text: Date of Application, 25th Jan., 1893
Complete Specification Left, 25th Oct., 1893-Accepted, 20th Jan.,
1894
PROVISIONAL SPECIFICATION.
Improvements relating to the Combustion of Fuel in Domestic and
other Fireplaces.
I WILLIAM HASSALL of Shelbrooke House, Ashby de la Zouch in the County
of Leicester, Manufacturer, do hereby declare the nature of this invention to be
as follows:—
The object of my present invention is to ensure a more complete combustion of
the fuel in the fire-places of stoves or grates, whether open or closed, and thereby
prevent the formation of smoke,-while at the same time effecting an economy in
the consumption of fuel.
By means of my invention, I am enabled to burn bituminous coal, or coal slack,
at a high temperature, with almost complete combustion of the smoke or gases
arising therefrom.
According to my invention, I construct these fireplaces on the regenerative
principle, and utilize the waste heat passing from the fires, and the heat stored up
in the fireplaces, for the purpose of heating the air that supports combustion. Thus,
I may burn an inferior fuel on the fire-bars or in the fire grates, and, at the same
time, obtain almost complete combustion of the gases given off, immediately a
fresh supply of fuel has been added to the fire.
In carrying out this invention, I provide an air chamber over, and at the back
of, the fire-place, with air passages in the side walls thereof, to convey air drawn
in from any convenient place, to the air chamber over and behind the fire place.
The portion of the air chamber at the back of the fire, is provided with a
number of small outlets, through which the heated air passes, as required for the
purpose of assisting in the combustion of the fuel on the bars, and the gases arising
from the fires. One side of the air chamber preferably forms the back of the
fireplace, and against which the solid fuel is placed, so that as the fuel burns, it
helps to maintain the high temperature of the air chamber.
The air chambers are placed in such positions as will ensure their being kept at
a high temperature when the fire is burning in the grate..
In both open and closed stoves and grates, I may have closed ash pits, and only
admit into these ash pits, and into the air chambers referred to, sufficient air to
support combustion of the fires and the gases arising therefrom.
I may use dampers to regulate the draught and control the fire, and by means of
suitable appliances, the supply of air to the respective parts of the fireplace or
combustion chamber is controlled and regulated.
The products of combustion may also pass through passages or flues traversing
the air chambers, to assist in heating the latter.
I may modify the construction of my improved fireplaces or combustion
chambers to meet varying requirements, but in all such modifications, I construct
these fireplaces or combustion chambers on the regenerative principle, and use
heated air for the purpose of supporting combustion therein.
It will be obvious that my invention will apply equally well to gas fires as to
solid fuel, or I may use a combination of gas and solid fuel.
Gas may also be used for primarily heating the air to start the fire, or otherwise,
as may be desired.
Dated this 25th day of January 1893.
FARANT 1 SON
NEWTON & SON,
Agents for the Applicant.

page_text: Improvements relating to the Combustion of Fuel in Domestic and
other Fireplaces.
I WILLIAM HASSALL of Shelbrooke House, Ashby de la Zouch in the County
of Leicester, Manufacturer, 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 statment :-
The object of my present invention is to ensure a more complete combustion of
the fuel in the fireplaces of stoves or grates, whether open or closed, and thereby
to prevent the formation of smoke, while at the same time effecting an economy in
the consumption of fuel.
By means of my invention, I am enabled to burn bituminous coal, or coal slack,
at a high temperature, with almost complete combustion of the smoke or gases
arising therefrom.
According to my invention, 1 construct these fireplaces on the regenerative
principle, and utilize the waste heat passing from the fires, and the heat stored up
in the fireplaces, for the purpose of heating the air that supports combustion.
Thus, I may burn an inferior fuel in the fire grates, and at the same time obtain
almost complete combustion of the gases given off, immediately a fresh supply of
fuel has been added to the fire.
In carrying out this invention, I provide air chambers over and at the back
and in the side walls of the grate or stove, with air passages to convey the air
drawn in from any convenient place to the air chambers, whence the air passes to
the fuel through a number of small outlets, as required, for the purpose of assisting
in the combustion of the fuel, and the gases arising from the fires. One side of
the air chambers preferably forms the back and sides of the fire place, and against
which the solid fuel is placed, so that as the fuel burns, it helps to maintain the
high temperature of the air chambers.
The air chambers are placed in such positions as will ensure their being kept at
a high temperature when the fire is burning in the grate.
In both open grates and closed stoves, I have closed ash pits, and only admit
into these ash pits, and into the air chambers referred to, sufficient air to support
combustion of the fires and the gases arising therefrom.
I may use dampers to regulate the draught and control the fire, and, by means
of suitable appliances, the supply of air to the respective parts of the fireplace or
combustion chamber is controlled and regulated.
The products of combustion may also pass through passages or flues traversing
the air chambers, to assist in heating the latter.
I may modify the construction of my improved fire places or combustion
chambers, to meet varying requirements, but in all such modifications I construct
these fireplaces or combustion chambers on the regenerative principle, and use
heated air for the purpose of supporting combustion therein.
It will be obvious that my invention will apply equally well to gas fires as to
solid fuel, or I may use a combination of gas and solid fuel.
Gas may also be used for primarily heating the air to start the fire, or otherwise,
as may be desired.
In the accompanying drawings, I have shown in Sheet I my invention as applied
to open fire places, and in Sheet II as applied to closed stoves.
Fig. 1, Sheet I, is a sectional elevation, and Fig. 2 a front elevation, of one
form of open fireplace.
Figs. 3 and 4 are similar views of a modified form.
Fig. 5, Sheet II, is a sectional elevation of a closed stove, and Fig. 6 is a plan
view thereof.

page_text: Fig. 7 is a sectional elevation of a modified form of stove.
Fig. 8 is a similar view of another form; and
Fig. 9 shows another modification.
Figures 10 to 16, Sheet III, illustrate other features of the invention, which
will be referred to in due course.
Referring now to Sheet I, A is the fire place, which is formed with a closed
bottom a, as in slow combustion stoves. Below the bottom a, is a space or closed
ash-pit, into which air passes from the front, the inlet being provided with
hit and miss valves, or other means for regulating the entrance of the air.
B is the back of the grate, which in Fig. 1 is hollow, and curves outwards, so as
to overhang the fire, in a manner and for a purpose now well understood. The
hollow space in this back B is in connection with the fire place A by small
passages, and the air to support combustion is conveyed from the ashpit 6 by the
passages d, which open into the upper part of the hollow space at two or more
points, as may be desired (see the dotted lines in Fig. 2).
C is a moveable canopy, the construction of which is now well known.
It will be seen that the fire burning in the grate will heat the overhanging back,
which, in turn, heats the air contained in the space, and the draught up the
chimney draws in the hot air, and keeps up the circulation, thereby improving the
combustion in the grate.
In Figs. 3 and 4, I provide the overhanging back B, as before, but in this case
it takes a slightly different form, being solid, and not hollow. I so arrange it,
however, as to leave a space behind in direct connection with the air passage or
ashpit b. This back may be a hollow block, open, at bottom, to the ashpit b. I
also provide side air chambers D, which are in connection with the air passage or
ashpit 6 by passages d, as before.
This arrangement of grate
may place in a suitable fireplace recess, as usual,
or it may be used standing out in the room, in which case I provide a flue D¹
connecting with the chimney.
The action will be practically the same as in Figs. 1 and 2.
In Sheet II the closed stove application is illustrated, thus:-E is preferably a
metal casing lined with fire brick, and circular, square, or oblong in cross section.
This casing I may divide into two parts by a transverse hollow partition E', open
at the top, and extending nearly to the bottom of the casing, and provided at top
with a valve. One of these parts E' I call the fire space, which is provided at
top with a charging door e, and at bottom with a clearing door f. Round this fire
space, and in the walls of the casing, I provide an air space F, which com-
municates with the fire space by suitable passages. The other half of the casing E'
I will term the flue space, which is in communication, direct or otherwise, with the
chimney.
Heated air passing down the hollow partition, enters both parts E' E' through
suitable openings, and mingling with the hot gases arising from the fire, causes
them to burst into flame, and thus produce good combustion.
In the flue space E³ 1 provide a kind of deflector g, which serves somewhat to
restrict the passage, and thus ensure a mingling of the gases and air.
External air is conveniently introduced to the air space F.
Instead of making the partition oblong, and transversely of the casing, I may,
in a cylindrical stove, employ a cylindrical and concentric air passage, with a
concentric flue either outside or inside.
Stoves of this kind are shewn in Sheet II; thus, Fig. 10 shews the air passage
passing down inside the flue, while Fig. 11 shews the reverse, the air passage being
outside the flue.
I prefer the flue outside the air passage, in which case it might stop short of the
bottom some distance, and be supported by feet, while the air passage may go to
the bottom, and draw the air either from the top or bottom, or both.
In these arrangements, the fire space would be all round the flue, and I may
provide two or more charging doors, in order to properly spread the fuel,

page_text: may also provide the internal swelling or deflector in the flue or air pipe, to
restrict the passage, as before mentioned.
Fig. 7 shews a somewhat similar construction of stove to that shewn in Figs. 5
and 6, but the partition is solid, and the air chamber is arranged in, and discharges
into, the flue space E³, as will be clearly understood from the figure.
In the arrangement shewn at Fig. 8, I dispense with the partition, and I provide
the air chamber all round the fire, except at the part required for the cleaning
door. The charging door I place, by preference, at about half the height of the
casing, and I restrict the upward passage of the gases by a conical portion of the
lining.
In all the arrangements shewn in Sheet II, I may introduce liquid fuel by a
pipe from a suitably placed reservoir i, and preferably into the flue space.
In the arrangement shewn at Fig. 9, I prolong and enlarge the flue, so as to
increase the heating surface, k being a baffle plate contained in a horizontal flue
on the top of the casing, to cause the hot gases to take a more or less circuitous
course.
The draught of the fire may be regulated by dampers placed in the chimney or
flues, say, near the outlet to the chimney, or the main air inlet may be regulated
by hit and miss, or other suitable valves in the charging doors, or in other parts,
while the supply of air may be regulated by hit and miss valves at the inlets of the
subsidiary air passages.
In Figs. 12, 13, 14, 15, and 16, Sheet III, I have illustrated the arrangements in
which the products of combustion pass through passages or flues traversing the air
chambers, to assist in heating the same; thus, E' E' represent the air chambers,
and E³ the flues.
In Fig. 12, I also illustrate the burning in combination of solid and gaseous fuel,
G being a gas burner of the "Bunsen" or other suitable type.
Figs. 13 and 14 illustrate the primary heating of the air by gas, to start the fire,
G being the gas burner, as before.
Figs. 15 and 16 shew an obvious modification in the arrangement of the transverse
hollow partition, the said partition being curved instead of straight; in other
respects the stove being the same as in Sheet II.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A fire grate having a hollow back, to which external air is admitted, to
become heated, and from which it is discharged through perforations into the fire,
as set forth.
2. A fire grate having a hollow back and hollow sides, to which external air is
supplied, and, when heated by coming into contact with the heated parts, is intro-
duced to the fire through suitable perforations in the back and sides, as and for the
purpose set forth.
3. In a closed stove, the use of a hollow perforated transverse partition, to supply
hot air to the centre of the fire, and also to meet the gases issuing therefrom, as set
forth.
4. In combination with semicircular or other shaped external passages, to supply
hot air to the fire, to produce combustion, a hollow transverse perforated partition,
as and for the purpose set forth.
5. In a closed stove, the use of air passages and chambers in the walls of the
stove, connected with the external air, and communicating by perforations with a
flue space formed in the casing by a solid transverse partition, as and for the
purpose set forth.
6. In a closed stove, the combination with a closed bottom, of air passages and
chambers in the walls of the stove, connected with the external air, and
communicating with the fire chamber by perforations, as and for the purpose set
forth.

page_text: 7. In a closed stove, the use of a hollow cylindrical air passage, in combination
with a concentric flue, either inside or outside the air passage, as set forth.
8. In a closed stove of the character referred to in Claims 3, 4, 5, 6 and 7,
restricting the exit from the flue space in the manner and for the purpose set
forth.
9. The construction and arrangement of fire places and stoves as herein shewn
and described.
Dated this 25th day of October 1893.
NEWTON & SON,
Agents for the Applicant.