An Improved Method of and Fire Box for Consuming Fuel so as to Prevent the Formation of Smoke.
Year: 1895

page_text: Date of Application, 26th Aug., 1895-Accepted, 26th Oct., 1895
COMPLETE SPECIFICATION.
An Improved Method of and Fire Box for Consuming Fuel so as to
Prevent the Formation of Smoke.
1, WILLIAM STYLES HAZELTON, of No. 13 Scott Street, St. Kilda, near
Melbourne, in the Colony of Victoria, Metallurgist, 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:-
This invention has been devised in order to provide a more economical and
efficient method of and firebox for consuming fuel in furnaces and other fire-places
such as for generating steam; cooking, annealing, ore roasting, or any other
metallurgical operation, its main object being to ensure perfect combustion of the
fuel without the generation of smoke and to provide for an automatic supply of fuck
to the fire.
Hitherto it has been usual to charge the fire box with a sufficiency of coal or
other fuel to last for a certain time and to ignite such fuel at the bottom and to
allow the flame and products of combustion to pass up through the body of fuel
and finally to escape into the atmosphere.
Now according to my invention I provide a comparatively high column of fuel
in a fire-box and consume only the lower portion or bottom layer by admitting air
to one side of said fire box near the fire bars and by providing an exit for the
products of combustion on the opposite side of said firebox both the inlet and the
outlet being arranged close to the fire bars so that the air admitted to support
combustion will only come in contact with the bottom layer of the fuel which will
thus be the only part in a state of incandescence, instead of as in the ordinary
arrangement nearly the whole of the fuel being incandescent and the draught
proceeding from the bottom upwards.
My invention also comprises certain improvements in the construction of the fire
box whereby hot air or a mixture of hot air and steam can be supplied to the
burning fuel and owing to my improved method fresh fuel will be automatically
supplied to the buruing mass as required thus obviating the necessity of such
constant stoking and attention as has been necessary heretofore.
Referring to the accompanying drawings,
Figure 1 represents a perspective view of a fire box constructed according to
this invention.
Figure 2 is a vertical transverse section on line 2-2 Figure 1.
Figure 3 is a perspective view of the hot air generating chamber and hollow fire
bars which I arrange inside the fire box as and for the purposes hereinafter
described.
Figure 4 is a vertical section on line 4-4 Figure 3.
Figure 5 is a similar view to Figure 1 except that it shows a fire box constructed
with the whole of my improvements.
Figure 6 is a vertical transverse section on line 6-6 Figure 5.
Figure 7 is a vertical cross section on line 7-7 Figure 6.
Figure 8 is a plan of the hot air generating chamber and hollow fire bars.
The same letters of reference indicate the same or corresponding parts in all
the figures.
For the sake of clearness I will first describe my invention by reference to the
first four figures only, because they show my invention in its simplest form without
some of the improvements that I have devised and can therefore be more readily

page_text: understood, the other improvements included in Figures 5 to 8 can then be more
easily explained, it being borne in mind that everything shown in Figures 1 to 4 is
included also in the subsequent figures with other additional improvements.
A represents the casing of a fire box which for the purposes of my invention is
made comparatively high and narrow and is adapted to be completely closed in at
top and bottom as shown, a feed door B being provided in its jupper portion to
enable the box to be charged with fuel and an ash-pit door C being provided at its
lower end in the ash-pit below the fire bars D whilst another door E is provided
opposite said fire bars and is provided with a slide F to regulate the admission of
air to the burning fuel.
G represents a hollow flue passage or chamber which is constructed around the
fire box at about the level of the fire bars and is used for heating the air before it
is supplied to the burning fuel.
This hot air generating chamber opens to the atmosphere through the slide F
and it is formed with a long slot or opening g extending nearly the full length
of the fire box along one side so that the air which is passed through it will be
discharged into the fuel about on a line with the fire bars D which latter
extend from front to back of said chamber and thus allow part of the air supply to
pass direct through them to the back of the chamber whilst the remainder passes
(in the example shown) through the right hand side and along the back of said
chamber before it can enter the fire box through the inlet g, a baffle plate g
(see Figure 8) being fitted across that side of the chamber to prevent the air
passing direct to the inlet,
J.
H represents the outlet opening which is according to my invention formed in
the fire box A opposite the inlet y and also comparatively close to the fire bars D
so that the supply of air for supporting combustion will pass almost in a
straight line across the bottom of the mass of fuel with which the box A is
charged and thus the bottom layer only of such fuel will be kept incandescent,
said outlet being made to extend from front to back of the fire box and of about
the same length as the fire bars.
By this means the smoke is drawn downwards and consumed.
h represents an inclined bar or plate which is fitted over the outlet H to
prevent the fuel as it passes downwards from dropping through said outlet and
at the same time form a "choke" to regulate the supply of fuel to the burning
layer.
I will now proceed to describe some further improvements by reference to
Figures 5 to 8, said improvements being in the construction of the hollow fire
bars D and means for generating steam therein to be supplied with hot air to the
fire and in the addition of what I term a caloric chamber to the fire box together
with a few minor improvements in the construction of some of the details of my
invention.
I represents said calorie chamber which is provided at the side of the fire box A
in which the outlet E is formed.
It may extend from top to bottom of the box as shown or if preferred need only
extend down to the bottom of said outlet and it can be fitted with liners or
movable fire plates i supported in suitable brackets in said caloric chamber.
If preferred this latter instead of being constructed as shown might and in
many instances would conveniently consist merely of a space left between the fire
box and the wall of an oven or roasting furnace, end of a boiler or other article
to which the fire box is to be applied. represents a hinged door or damper
adapted to open or close the upper end of either the fire box A or the caloric
chamber 1. This enables the fire box to be used in the ordinary way that is, with
the flames passing up through it if required as would sometimes be the case where
it was required to open the fire door E in order to attend to the fire bars or for
any other purpose, or where only a low heat is required as for cooking &c., or for
cooling down the furnace or to enable it to be used as an ordinary furnace with
ouly a small depth of fuel over the firebars.

page_text: The inclined bar or plate over the outlet H is preferably made removable aud
may be supported upon brackets at each end of the box as illustrated in
Figure 7.
In order that steam may be supplied to the burning fuel together with the
hot air I provide means whereby a small quantity of water may be fed into the
hollow fire bars D. For this purpose I form or provide a narrow water supply
tank K on one or more of the sides of the fire box A a small removable plate
or cover being provided so that it may be conveniently filled.
A tap in the lower end of this tank enables the water to be fed down a
pipe into a trough passing along across the front of the hollow fire bars D
and provided with small notches or openings opposite each of said bars so that
the water can pass into them.
To prevent said bars from being cracked by the contact of the cold water
whilst in a heated condition I form them with an inner lining d which can readily
be renewed when worn out or destroyed.
It will be readily understood that the steam generated in the hollow bars D will
pass with the air travelling through them into the back of the hot air generating
chamber G where it will meet the air which has passed around the right hand side
of said chamber and will finally be discharged together with such air through the
inlet g into the burning fuel.
If preferred the steam might be fed direct into the fire bars from a boiler or
other convenient source as will be readily understood.
With this method of consuming fuel at the bottom only in a fire box constructed
as above described an intense heat can be obtained without the production of
smoke thus making it eminently suitable for calcining or other furnaces used in
metallurgical operatious although even in its simpler form it possesses many
advantages for cooking or other domestic purposes.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
First. The herein described method of consuming fuel so as to prevent the
formation of smoke consisting in admitting air only or air and steam near the
lower end of a comparatively high column of such fuel and in allowing the flame
and products of combustion to escape only from the opposite side of said fuel
at or about on a level with the air inlet, so that only the bottom sheet or layer
of fuel will be rendered incandescent substantially as specified and as illustrated
in the accompanying drawings.
Second. A fire box for consuming fuel baving its upper and lower portions
completely enclosed and provided with an air inlet a short distance above the
fire bars and an outlet in approximately the same position on the opposite side
of the box substantially as specified and as illustrated in the accompanying
drawings.
'
Third. In a fire box a hot air generating chamber (such as G) extending around
said box and fitted with hollow fire bars passing from front to rear of said box and
having a slot or opening (such as g) extending nearly the whole length of the fire
box along one of its sides, a baffle plate (such as g¹) being fitted across the slotted
side so as to cause the air to pass both around said chamber and through said
hollow bars substantially as specified and as illustrated in the accompanying
drawings.
Fourth. In a fire box hollow fire bars fitted with removable liners (such as d)
substantially as specified and as illustrated in the accompanying drawings.
Fifth. In a fire box a door or damper (such as 2) in combination with a caloric
chamber (such as I) said door being arranged to open or close the upper end of
either said fire box or said caloric chamber substantially as specified and as
illustrated in the accompanying drawings.
Sixth. In a fire box the combination of a tank (such as K) in the side thereof

page_text: together with a trough (such as k*) extending across the front of hollow fire bars
(such as D) substantially as specified and as illustrated in the accompanying
drawings.
Dated this Eighteenth day of July One thousand eight hundred and
WILLIAM STYLES HAZELTON.