Improvements in Apparatus for Burning Fuel, applicable for Domestic, Manufacturing, and other purposes
Year: 1890

page_text: Date of Application, 3rd Jan., 1890
Complete Specification Left, 1st Oct., 1890-Accepted, 24th Jan., 1891
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Burning Fuel, applicable for
Domestic, Manufacturing, and other purposes.
WILLIAM POTTS No. 30 Castle Street Edinburgh, Pneumatical Engineer &c. do
hereby declare the nature of this invention to be as follows:-
The purposes instigating to these improvements were, obviating defilement of the
atmosphere by smoke, avoiding the large loss in the very considerable part of the fuel
placed on an open fire, from the vertical flue over it absorbing a very large part of
the heat emanating from the fuel's combustion, and also placing the burning fuel as a
scientific process for obtaining heat under the control which such a chemical change
in matter needs, experiments long ago proved to the designer that so long as a
flue was connected with a fire to lead to the outer air, the deplorable waste, and the
nuisances must exist but how to pass light air and vapour into the cold outer air,
and how to draw air in, to cause brisk burning, has consumed many years of time
caused anxious thought, but long ventilating experience lately placed in view the
constructions now patented which consecutively draw in air and take out vapour,
the Specification details the chemistry of fuel burning.
These improvements avoid largely the forming smoke, very largely burn the
comparatively very small quantity of smoke produced, and these in combination
with an allied construction, in an instrument patented at this date viz. a ventilating
wall outlet, get rid in enclosed spaces of the unwholesome products from fuel com-
bustion, this plan having no flue over the fire, or any outlet from that higher than the
wall of the building.
Another improvement that secures the specific purifying and economic advantages
described is designed to be used on existing chimneys where it is desired to use the
means for burning fuel here alluded to, in front of an existing chimney, this is a
vertical outlet patented at this date as a ventilating construction, but this like the wall
outlet will not admit an air current from outside it.
In order to evidence the scientific character of these improvements, a brief
description of smoke is necessary.
Smoke is mainly steam united to hydro-carbon gas and ensues partly from water in
fuel, but results much more from air being allowed to pass to the top of the fire. On
the plan in use air descends the flue, and also flows from the room, the oxygen from
the air unites at the heat with the soon evolved hydrogen gas, these form water,
which instantly becomes steam, in the midst of the hydro-carbon gas hence originates
smoke.
The grate construction now described can only take air from the ash box, until the
sliding fronts to fire are lifted by means of the balance weights.
The carbon anhydride gas evolved after the hydrogen is gone requires to be passe l
out of the building, and on this plan a shallow airtight metal pilaster is fixed from
back of grate, connected airtight to the ventilating wall outlet before alluded to for
the purpose of drawing away to the outer air, the vapour and incombustible gases
that are noxious.
The plan of construction 21, has a fire-place with four sides, and at its back an
adjoining passage, which has an opening at top from the fire chamber for the smoke
evolved through a brief period when fuel is put on, to descend the passage to the back
of the fire, when the portion not burned takes the upward current to the back of the
fire till it is consumed. From the fire being when necessary enclosed from air
excepting at its entrance from below the fire from the ash box, the draught is very
quick, the heat intense, and after the hydrogen is evolved, the coke carbon forms not
sinoke but carbonic anhydride, which highly deleterious, but at this point the

page_text: passage to the discharging pilaster is opened by raising the valve at it, which operation
closes the passage to the back of the fire, which as smoke has disappeared is not now
required, the updraw in the wall outlet is so persistent and great, as to draw then air
from the room. But the raising partly the fronts to the fire's sides is used discretionary,
when it is wished to have an open fire, after smoke has ceased, air can be thus admitted
to it; the register valve in the ash box may be in any desired degree closed; this
process of burning fuel is thus under control, as to rate of burning, the valves
instantly extinguish fire, by excluding air.
Another important feature in this plan is that from the natural vertical flow of heat,
very little if any latent heat escapes from the place where this plan for burning fuel
is used, as the vapour or gas enter a downward current to the pilaster described when
the valve to that is opened on smoke disappearing for the drawing up power of the
outlet is considerable and constant from natural law; but heat is immaterial, and
though a concomitant of a vapourous condition of matter, the heat evolved from
burning is greatly latent, while the vapour is attracted downward by the current set
going at the outlet.
Thus the estimated loss of ths of the heat by useing a chimney is by this plan
mainly avoided.
Another great advantage arises from soot not being formed as that is condensed
smoke. This plan includes means for moistening the heat emitted at the top of the
grate is a water vessel having a perforated cover to allow evaporation, and points out
the value of this plan where steam is used on land or sea. This plan gives the means
of proportioning the size of fire to the need for it, as on each side of the grate, a
moveable piece can be taken out to increase the area for burning in. The valve in
passage also controls the rate of current of air from room.
2
Either the hollow pilaster, or a fireclay channel at back of floor skirting can be
used to pass to the pneumatic outlet the vapour from burning fuel. The hollow
pilaster described is a channel communicating with the pneumatic ventilating wall
outlet described previously. Over grate is a water vessel having a perforated cover.
There is a coal box adjoining the back passage for smoke to the fire. The narrow
channel adjoining it is for a current of air to pass through to prevent the fuel getting
too hot from its being near the channel at the back of the fire, down which the
smoke takes a circuit current to the back of the fire. Chains moving on pulleys
move in grooves the front covers to the fire.
There are two sides to fire grate, which is quadrilateral in plan. The ash box has
register slidė valves to three sides of it. The vapour passage from the top of the fire
to the pilaster is previously described.
There is a hinged valve plate to close the passage to the back of the fire when
smoke has disappeared, and its elevation for that purpose opens the passage to the
pilaster to allow outflow of the carbonic vapour, when contemporaneously the covers
to fronts of the fire may be raised at discretion.
As there is no vertical outlet from the grate for heat above the fire, that is either
evaporating the water or flowing into the room, the heat emitted being dry requires
to be moistened by the evaporation of the water, no escape externally is appreciable
of heat from the room, therefore on this plan of burning in front of wall, all the heat
may be considered as used, while the air admitted through the ash box is controllable.
The positive draught of air through the fire by means of the pneumatic draught
through the wall outlet, which is considerable, up or down combined with the
excluding all air from over the fire till the hydrogen is gone, and water not produced
over the fire, places the use of fuel in a scientific form economically. The channel
from the ash box leading to the pilaster ensures as long as the register valves in ash
box are open a draught of air from the room to the fire by the pneumatic action in
the wall outlet.

page_text: COMPLETE SPECIFICATION.
Improvements in Apparatus for Burning Fuel, applicable for
Domestic, Manufacturing, and other purposes.
I WILLIAM POTTS, Pneumatical Engineer, residing at No. 2 Alva Street
Edinburgh 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 :-
1. These improvements relate to a plan for burning fuel that differs much from
that in use, as it avoids greatly loss of heat, also production of smoke, and in the
construction for domestic use directs heat into the room.
2. It is believed to be applicable wherever heat is required, but the drawings show
three constructions for its application viz. for domestic use, for the production of
steam, and a smith's hearth.
3. The domestic fire is termed a calorifier Fig. 1 in profile drawing. The fire
chamber is A, the air admitted under the fire at B, the ash box at C. The fire
chamber is necessarily enclosed from the air above the fire by a covering of sheet
asbestos resting on a plate at the back of the fire, and turning above to the front of
the metal case, as shown by dotted lines, the fire is so enclosed. to exclude air above
the fire because if air reaches the fire there, the oxygen in the air unites with.
hydrogen evolved, forming water, which becomes instantaneously steam, that mixing
with the bydro-carbon gas becomes smoke. No channel exists above the fire to
carry outwardly away heat, but the heat passes rapidly through the asbestos caseing
into, and through the compartment G into the room.
The heat on entering G gets into a current of fresh air from the channel H which
commences at this outer wall and is placed over the pneumatic outlet Fig. 1 in
Specification No. 114 A.D. 1890, the valve Ha, in H controls the quantity of air. The
pneumatic outlet Fig. 1 has a dual effect from its peculiar construction, and its
position in an outer wall, it draws air from the room to the fire, and on the same line
of draught, draws out of the fire through the channel 1 at its back downwards, the
unused part of atmospheric air, and gaseous products from combustion, which it
discharges at the outer wall.
For avoiding smoke in this plan, the fuel is dried necessarily before reaching the
fire, and by preference over the fire as shown in the drawings, this is effected at
Fig. 1 by placeing fuel in box E at the top lid F, the box opens at the bottom
downwards by loosing the chain. This description implies that the designer of this
plan assigns the emanation of smoke to the forming steam over a fire. The frame
above A holds a plate of mica to slide down on wires to control, or exclude air at
front of fire at A. Fig. 2 is ground plan of calorifier showing its general outline,
and the perforated bottom plate of fire chamber J. K shows the fresh air channel.
4. Fig. 3 shows elevation of a furnace to produce steam, the boiler to be placed
over it, forms no part of this plan, but no channel, or opening to the outer air exists
or is allowed on this plan above the fire.
L is the furnace, M the coal box, N N are boxes moving by wheels on rails through
openings in the walls S S to be filled. O is the chamber to supply air through the
perforated bottom plate of the fire. P P are walls to furnace, preferably of fire clay,
and perforated as lines show to about half the height of fire to admit air to its sides
from the openings at the front QQ R R are frames having sliding fronts, which
can be used to proportion or exclude air at the sides of furnace. The gaseous
products from combustion are drawn away downwards at the back of furnace, by the
draught of, and into a pneumatic outlet described for the domestic calorifier Fig. 1.
5. Fig. 4 shows elevation for, and Fig. 5, the plan for a smith's hearth. Air feeds
the fire box T from the chamber U underneath, the gases from combustion are drawn
away from the fire down the channel V to and by the draught action of a pneumatic
outlet fixed in an outer wall described before. The fire chamber has a cover X a
supported from ceiling or roof by rods X X X X, the coal box Y is fixed to the

page_text: cover. W, W are doors hinged to the sides of S, air is thus excluded from space
above the fire, till access to the fire is needed. The constructions for all, will
be of ordinary material, and can be made by general manufacturers to suit the
circumstances, by a proportionate increase of the sizes of the parts drawn.
The pneumatic outlet referred to with the drawings is Fig. 1 in Specification
No. 114 A.D. 1890, but Fig. 2 is applicable where a vertical discharge is preferred.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare what I
claim is
1. I claim the plan to construct fire chambers meaning any enclosed spaces,
without these having any channel above the fire, that communicates on an ascending
line with the external atmosphere.
2. I claim the having fire chambers constructed with an aperture channel at the
back properly proportioned, to carry away the unused portion of the atmospheric
air, and gaseous products emanating from burning fuel.
3. I claim the use of both pneumatic outlets Figs. 1 and 2 in Specification No. 114
A.D. 1890 to connect to the said aperture channel to remove to the external
atmosphere the said aerial or gaseous products.
4. I claim the introduction by a channel above the pneumatic outlet Fig. 1 before
alluded to, to bring in fresh air to the domestic calorifier at its back as specified to
give current to the room of the fire heat through a perforated channel over the fire
chamber.
5. I claim the plan of drying fuel, and also the doing that by placing a coal box
above the fire constructed to open for discharging as described.
6. I claim the plan of placeing in front of the fire a frame sliding on wires at the
sides and holding a mica panel to enclose the fire front to diminish or exclude air
from the fire there.
7. 1 claim to enclose the fire above it by sheet asbestos or other suitable material
as specified, to prevent air reaching the fire from above.
8. I claim in furnaces having a passage for air on the sides with communicating
narrow channels to fire as specified.
9. I claim the construction of a smith's hearth as drawn and specified.
Dated this 30th day of September 1890.
WILLIAM POTTS.