IMPROVEMENTS IN APPARATUS FOR PRO- DUCING HEAT BY THE COMBUSTION OF INFLAMMABLE GASES OR VAPOURS
Year: 1877

page_text: LETTERS PATENT to Matthew Piers Watt Boulton, of Tew Park, in the County
of Oxford, for the Invention of "IMPROVEMENTS IN APPARATUS FOR PRO-
DUCING HEAT BY THE COMBUSTION OF INFLAMMABLE GASES OR VAPOURS."
PROVISIONAL SPECIFICATION left by the said Matthew Piers Watt Boulton
at the Office of the Commissioners of Patents on the 24th February 1877.
MATTHEW PIERS WATT BOULTON, of Tew Park, in the County of Oxford.
"IMPROVEMENTS IN APPARATUS FOR PRODUCING HEAT BY THE COMBUSTION OF
INFLAMMABLE GASES OR VAPOURS."
This Invention relates to apparatus for the production of heat by the combustion
of gas or inflammable vapour.
In the following descriptions I shall use the word gas to express the combustible
fluid supplied to the apparatus, it being understood that the apparatus described is
equally applicable to the combustion of inflammable vapour, or when fluid other
than pure gas is so supplied. Thus in some cases the material supplied to the
apparatus may be a jet of air or steam, or elastic fluid mixed with inflammable gas
or vapour, or carrying along with it in suspension fine particles of inflammable
matter.
Fig. 1 represents a vertical section of one form of apparatus which I employ.
This pipe
A is the pipe which supplies the gas to issue as a jet from the orifice o.
can be raised or lowered by means of a screw B. The gas enters it from the
vessel C which is supplied by the pipe D from the gas main or reservoir; e is a
passage with suitably inclined sides by which the air is introduced to mix with the
gas which issues from the orifice o; F is a passage of varying area in which the
gas and air are mixed. This passage terminates in two orifices i, i, of rectangular
section (as shewn in the plan Fig. 1a), through which the mixture of gas and air issues.
Between the passages leading to the orifices i, i, is a cavity G communicating
freely at each side with the atmosphere, so that air rises through it between the
passages i, i, and mixing with the gas and air issuing from them supports com-
A

page_text: bustion along with them. Thus air is supplied to support combustion on both sides
of the passages i, i.
Instead of making the terminal passages continuous longitudinally, they may be
divided into numerous smaller orifices surrounded by air on all sides, as shewn in
section at Fig. 2, and in plan at Fig. 2a, where i, are the orifices through
which the mixed air and gas issue, and a, a, are spaces between them open to
the air.
Another construction of burner is shewn in Fig. 3; here F, F, is a passage of
circular section of varying area, containing two enlargements and contractions, in
which the gas and air are mixed, and C is a chamber in fire-brick or other refractory
material D in which the combustion takes place. The upper surface of this com-
bustion chamber is made with sloping sides e, e, to radiate heat upwards.
Another form is shewn by the dotted lines b, b, applicable when it is desired to
direct the heat against a smaller surface.
A similar combustion chamber may be applied to the burner of the kind shewn
in Fig. 1. I prefer in many cases to make these combustion chambers adjustable,
so that they can be raised or lowered at pleasure. Or the tube or passage beneath
them may be made adjustable, so that it can be raised or lowered at pleasure...
When it is desired to burn a large quantity of gas, I prefer to employ an arrange-
ment of annular passages for the mixture of gas and air, as shewn by the vertical
section, Fig. 4, the advantage of such an arrangement being to diminish the length
of the passage in which the mixture takes place.
In Fig. 4 A, A, is a passage of cylindrical section terminating in the annular
orifice i, i. Gas is supplied to the passage A, A, from the chamber B, B, which
receives it from the pipe c, communicating with the gas reservoir.
Air is supplied
to the interior space D through apertures controlled by the slide or valve E; air is
also supplied to the exterior space F through apertures controlled by the slide or
valve G. The exterior and interior currents of air meet the annular jet of gas
issuing from the orifice i, and pass with it through the throat o into the passage H,
which I prefer to make of varying area by means of a suitably shaped core L in
order to promote mixture of the elastic fluids as they pass through it. From H
they pass to the throat I; from this throat they may issue directly into a passage.
in which they mix with a further quantity of air, as shewn in Fig. 3, or they may
pass on to a passage and orifice of any form desired.
Fig. 5 shews one form of passage which may be employed for this purpose,
terminating in an annular orifice; here I is the throat by which the mixed gas and
air enter from the lower portion of the passage, which may have the form shewn in.
Fig. 4, or any other suitable form. From this the mixture passes on into the
chamber B, of circular section, and terminating in an annular orifice i; C, C, are,
tubes which pass through the chamber B and convey air into the interior space D
from the chamber E¹, the supply into which is controlled by means of the valve or
slide F; E is another chamber for the supply of air, and F the slide or valve for
regulating the supply of air to it. The air from D passes through the channel o
and joins the annular current of mixed gas and air issuing from the annular orifice i;.
the air from E passes through the channel o¹ on the other side of the annular
current and joins it from that side. The gas and air pass through the throat H
of the combustion chamber formed in refractory material which is a slow conductor
of heat, such, for instance, as fire-brick. The heat of the combustion may be applied
to any required purpose, such as heating of crucibles, muffles, and the like, or to the
heating of boilers.
In the Figure, K may be supposed to be the bottom of a
boiler.
In other applications the form of the flues or passages may be altered to suit the
form of the body to which the heat is applied.
I shew in Fig. 6 one arrangement of apparatus in connection with a boiler, the
form of boiler shewn being one of well known construction; here the combustion.
takes place in the chamber G formed in fire-brick or similar material, and the
products of combustion after, issuing from this chamber strike on C, C, the curved

page_text: bottom of the boiler, by which they are deflected in all directions, and pass away
by the flues, as shewn, to the chimney; A' is the chamber for supplying air to the
outside of the annular current issuing from the orifice i, i, and A that for supplying
air to it from the interior; F1 and F are slides or valves adjustable by hand for
regulating the area of the apertures through which the air enters these chambers;
Vand V are additional slides or valves acted on by a governor of any known
construction, so as to increase the area for admission of air as the pressure in the
boiler falls, and to diminish it as the pressure rises; similarly FS is a slide or valve
adjustable by hand for regulating the area of passage for air into the lower
chamber A³, where the first admission of air to the gas takes place, and V3 is a
valve connected with the governor, also for regulating this area; V* is a slide also
connected with the governor which regulates the area for the passage of the gas to
the jet, increasing it in a similar manner as the pressure in the boiler falls and
diminishing it as it rises.
I prefer so to arrange the valves above mentioned that they can be connected or
disconnected with the governor at pleasure. This may be effected, as shewn in
Fig. Ga, by arranging the stems connected to the slide valves, so as to work in
slotted holes in the vertical bars M, providing in each case a catch N which can be
turned aside when the valve is to be disconnected, as shewn at N¹. When they are
connected the combustion is regulated automatically, according to what is needed;
when the pressure in the boiler falls the combustion and heat are increased, when
it rises, the combustion and heat are diminished; and while this variation takes
place the proportions of gas and air needed for efficient combustion remain the same,
or nearly so.
In the Drawing I have for simplicity shewn the lower part of the burner of a
simple form; but the same arrangement of valves may be employed when it has
other forms, such, for instance, as that shewn in Fig. 4.
In cases where the conditions of pressure are constant, the valves or doors
adjustable by hand might be omitted; suitable areas for the admission of air to the
chamber having once been determined, these might remain unaltered, axcept as
varied by the action of the governor. But in most cases the conditions of pressure
are variable; and when this is so the further provision of the valves adjustable by
hand is useful.
In some cases the adjustment effected by the governor may be applied to the
valves of the lower air chamber and of the gas supply only.
When it is desired to use the engine intermittently, it may be useful to employ a
small separate flame to maintain the heat and pressure in the boiler, while the engine
does not work. This may be done by applying a burner to an orifice P in any con-
venient part of the boiler flue.
It is generally desirable to have a means of inspecting the flame in the combustion
chamber as the colour of this indicates the degree of completeness obtained in the
combustion. This may be done by means of a passage Q in the extremity of which
a piece of glass or talc is inserted. The same passage may be used for kindling the
gas, or a separate passage may be provided for this purpose.
It is obvious that apparatus such as above described may be applied generally to
various forms of boiler; all that is needed being to vary the forms of flues or passa-
ges through which the products of combustion pass. Also the heat passing through
the combustion chamber may be utilised to impart heat to the entering air.
I shew in Fig. 7 a construction of this kind applied to a combustion chamber of
form somewhat different from that shewn in Fig. 6, but equally applicable to the
latter. In Fig. 7 A is the slide or valve which regulates the admission of the air.
The air admitted through it enters the casing b and passes thence through the pas-
sage e, in which it receives heat through D, the material surrounding the combustion
chamber C. From e the air passes to meet the mixed fluid issuing from the orifice
i. t is an orifice for inserting a kindling flame and for inspection. The construction
is shewn in Fig. 7 as applied to a flat-bottomed boiler, but like the constructions
previously described it is applicable when the heat is employed for other purposes.

page_text: The fire brick or other material used for the construction of the combustion cham-
bers may be built up of numerous pieces, according to any of the known modes of
construction.
When the heat is applied to the heating of boilers, a combustion chamber of fire
brick or like material may be dispensed with, but generally I prefer to employ it.
One advantage resulting from its use is that the heat of the chamber serves to
rekindle the flame in case of its extinction.
In the various forms of burner or mixing apparatus above described, it is not
absolutely necessary to take in a second supply of air; they are capable of being used
without this. But I consider it preferable to take in the second supply of air, one
advantage of this being that the top of the burner is kept cool, and another that
there is less risk of the flame striking back. Also in all the forms of burner above
described instead of drawing the air by means of the jet of gas the gas and air may
both be forced by means of a blower or forcing apparatus. Or the air may be
forced by such an apparatus and the gas drawn in by it.
When it is desired to produce intense heat oxygen may be used instead of air.
By the use of oxygen a heat may be produced greater than the walls of any furnace
are capable of resisting. When it is desired to operate with such a heat an arrange-
ment may be used like that shewn in Fig. 8. Here A is a basin formed of lime, in
the cavity of which the material B which it is desired to subject to heat is placed.
C, C, are chambers into which a mixture of oxygen and combustible gas is forced in
suitable proportions by a pump or forcing apparatus. O is a chamber into which
oxygen is forced in like manner.
The relative position of the oxygen and the mixture may obviously be inverted.
o, o, i, i, are annular passages which may be formed in refractory material or may
pass through a water casing. The oxygen issues in an annular jet, and on either
side of it the mixture of oxygen and combustible gas issues in an annular jet,
directed so as to impinge upon the central jet of oxygen. The stream of products
of combustion strikes down on the material placed in the cavity of the lime. The
products of combustion acting in the basin A rise to the flue H, mixing as they rise
with a sufficient quantity of air to reduce their temperature.
In employing this apparatus in order to obtain still greater intensity of heat, the
gas which is used unmixed, whether this be the oxygen or the gas which is burnt
with it, may be supplied in a heated state. In this case I prefer that this heated
gas should issue through nozzles or passages formed in refractory material which is
a slow conductor of heat, while the mixed gases pass through passages kept
cool by water jacketing, in order to prevent the flame from striking back.
"
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Matthew Piers Watt Boulton in the Great Seal Patent Office on
the 16th August 1877.
MATTHEW PIERS WATT BOULTON, of Tew Park, in the County of Oxford.
IMPROVEMENTS IN APPARATUS FOR PRODUCING HEAT BY THE COMBUSTION OF
INFLAMMABLE GASES OR VAPOURS."
This Invention relates to apparatus for the production of heat by the com-
bustion of gas or inflammable vapour.
In the following descriptions I shall use the word gas to express the combustible
fluid supplied to the apparatus, it being understood that the apparatus described is
equally applicable to the combustion of inflammable vapour, or when fluid other
than pure gas is so supplied. Thus in some cases the material supplied to the
apparatus may be a jet of air, or steam, or elastic fluid, mixed with inflammable gas
or vapour, or carrying along with it in suspension fine particles of inflammable
matter.

page_text: Fig. 1 represents a vertical section of one form of apparatus which I employ. A is
the pipe which supplies the gas to issue as a jet from the orifice o. This pipe can
be raised or lowered by means of a screw B. The gas enters it from the vessel C
which is supplied by the pipe D from the gas main or reservoir; e is a passage with
suitably inclined sides, by which the air is introduced to mix with the gas that
issues from the orifice o; F is a passage of varying area in which the gas and air are
mixed. This passage terminates in two orifices i, i, of rectangular section (as shewn
in plan, Fig. 1a), through which the mixture of gas and air issues. Between the
passages leading to the orifices i, i, is a cavity G communicating freely at each side
with the atmosphere so that air rises through it between the passages i, i, and
mixing with the gas and air issuing from them supports combustion along
with them. Thus air is supplied to support combustion on both sides of the
passages i, i.
Instead of making the terminal passages continuous longitudinally, they may be
divided into numerous smaller orifices surrounded by air on all sides, as shewn in
section at Fig. 2, and in plan at Fig. 2a, where i, i, are the orifices through
which the mixed air and gas issue, and a, a, are spaces between them, open to
the air.
°
Another construction of burner is shewn in Fig. 3. Here F, F, is a passage of
circular section of varying area, containing two enlargements and contractions,
in which the gas and air are mixed, and C is a chamber in fire-brick or other
refractory material D, in which the combustion takes place. The upper surface
of this combustion chamber is made with sloping sides e, e, to radiate heat
upwards.
Another form is shewn by the dotted lines b, b, applicable when it is desired to
direct the heat against a smaller surface.
A similar combustion chamber may be applied to the burner of the kind shewn
in Fig. 1. I prefer in many cases to make these combustion chambers adjustable,
so that they can be raised or lowered at pleasure. Or the tube or passage beneath
them may be made adjustable, so that it can be raised or lowered at pleasure.
When it is desired to burn a large quantity of gas I prefer to employ an arrange-
ment of annular passages for the mixture of gas and air, as shewn by the vertical
section, Fig. 4, the advantage of such an arrangement being to diminish the length
of the passage in which the mixture takes place.
In Fig. 4 A, A, is a passage of cylindrical section terminating in the annular
orifice i, i. Gas is supplied to the passage A, A, from the chamber B, B, which
receives it from the pipe c communicating with the gas reservoir. Air is supplied
to the interior space D through apertures controlled by the slide or valve E. Air is
also supplied to the exterior space F through apertures controlled by the slide or
valve G. The exterior and interior currents of air meet the annular jet of gas
issuing from the orifice i, which may consist of a ring of holes, and pass with it
through the throat o into the passage H, which I prefer to make of varying area by
means of a suitably shaped core I in order to promote mixture of the elastic fluids
as they pass through it. From H they pass to the throat I. From this throat
they may issue directly into a passage in which they mix with a further quantity
of air, as shewn in Fig. 3, or they may pass on to a passage and orifice of any form
desired.
Fig. 4a shews a modified construction of annular burner with a mixing passage of
varying sectional area, having a hollow core which serves as an air passage. Here
i is the annular orifice through which the gas issues, being supplied to it from the
chamber B. Air is supplied externally to mix with the gas through the valve A.
Air is also admitted into the space C in the interior of the annular burner.
A por-
tion of air is admitted through the valve E to mix with the gas issuing from i, while a
further portion is admitted through the valve F to the interior of the core L, to mix
with the current of gas and air issuing from the annular orifice I. The current
issuing from I, along with the air supplied to it on both sides, may pass into a com-
bustion chamber of any known form of construction. The chamber H in which the

page_text: gas and air mix previous to issuing from the orifice I may be formed if desired with
numerous contractions and expansions. The gas jet may be spread out into annular
forin, as shewn in Fig. 4b. Here R is a rod supporting a core L of circular section;
i is the orifice through which the jet of gas issues from the pipe A supplied from the
vessel B. This jet impinges on the lower portion of the core L, and flows off in all
directions in a thin sheet, passing to the throat o. Air is admitted by the valve G,
and a current of this passes also through the throat o. The gas and air mix in the
chamber beyond the throat o. If desired this chamber may be formed with
numerous contractions and expansions; shews a rod by which, instead of or in
conjunction with R, the core L may be supported, this rod being supported on the
sides of the exterior casing. The inixed current of gas and air issuing from the
annular orifice I may be treated as has been previously described, and may pass
into a combustion chamber of any known form. One form is indicated in the
Figure. The mixture of gas and air issuing from an orifice, such as that at I in
Fig. 4, may be mixed with a farther quantity of air in a passage of annular form,
one construction of which is shewn in Fig. 5. Here I is the throat by which the
mixed gas and air enter from the lower portion of the passage, which may have the
form shewn in Fig. 4, or any other suitable form. From this the mixture passes on
into the chamber B of circular section and terminating in an annular orifice i;
C, C, are tubes which pass through the chamber B and convey air into the
interior space D from the chamber E', the supply into which is controlled by means
of the valve or slide F¹; E is another chamber for the supply of air, and F the slide
or valve for regulating the supply of air to it. The air from D passes through the
channel o and joins the annular current of mixed gas and air issuing from the
annular orifice i, the air from E passes through the channel o' on the other side of
the annular current and joins it from that side. The gas and air pass through the
throat H of the combustion chamber formed in refractory material which is a slow
conductor of heat, such for instance as fire-brick. The heat of the combustion may
be applied to any required purpose, such as heating crucibles, muffles, and the
like, or to the heating of boilers. In the Fig. 5 K may be supposed to be the
bottom of a boiler.
In other applications the form of the flues or passages may be altered to suit the
form of the body to which the heat is applied.
I shew in Fig. 6 one arrangement of apparatus in connection with a boiler, the
form of boiler shewn being one of well known construction. Here the combustion
takes place in the chamber G, formed in fire-brick or similar material, and the
products of combustion after issuing from the chamber strike on C, C, the curved
bottom of the boiler, by which they are deflected in all directions, and pass away by
the flues, as shewn, to the chimney; A¹ is the chamber for supplying air to the out-
side of the annular current issuing from the orifice i, i, and A2 that for supplying
air to it from the interior; F and F are slides or valves adjustable by hand for regu-
lating the area of the apertures through which the air enters these chambers; V₁ and
V2 are additional slides or valves acted on by a governor of any known construction;
so as to increase the area for admission of air as the pressure in the boiler falls,
and to diminish it as the pressure rises. Similarly F³ is a slide or valve adjustable
by hand for regulating the area of passage for air into the lower chamber A³, where
the first admission of air to the gas takes place, and V3 is a valve connected with
the governor, also for regulating this area; V is a slide also connected with the
governor which regulates the area for the passage of the gas to the jet, increasing
it in a similar manner as the pressure in the boiler falls, and diminishing it as
it rises.
I prefer so to arrange the valves above-mentioned that they can be connected or
disconnected with the governor at pleasure. This may be effected, as shewn in
Fig. 6, by arranging the stems connected to the slide valves so as to work in
slotted holes in the vertical bars M, providing in each case a catch N which can be
turned aside when the valve is to be disconnected, as shewn at N¹. When they are
connected, the combustion is regulated automatically, according to what is needed;

page_text: when the pressure in the boiler falls, the combustion and heat are increased; when
it rises, the combustion and heat are diminished; and while this variation takes
place, the proportions of gas and air needed for efficient combustion remain the
same, or nearly so.
In the Drawing I have shewn for simplicity the lower part of the burner of a
simple form; but the same arrangement of valves may be employed when it has
other forms, such for instance as that shewn in Fig. 4.
In cases where the conditions of pressure are constant the valves or doors adjust-
able by hand might be omitted; suitable areas for the admission of air to the
chamber having once been determined, these might remain unaltered except as
varied by the action of the governor. But in most cases the conditions of pressure
are variable, and when this is so the further provision of the valves adjustable by
hand is useful.
In some cases the adjustment effected by the governor may be applied to the
valves of the lower air chamber and of the gas supply only.
When it is desired to use the engine intermittently it may be useful to employ a
small separate flame to maintain the heat and pressure in the boiler, while the
engine does not work. This may be done by applying a burner to an orifice P in
any convenient part of the boiler flue.
It is generally desirable to have a incans of inspecting the flame in the combus-
tion chamber, as the colour of this indicates the degree of completeness obtained
in the combustion. This may be done by means of a passage Q, in the extremity
of which a piece of glass or tale is inserted. The same passage may be used for
kindling the gas, or a separate passage may be provided for this purpose.
It is obvious that apparatus, such as above described, may be applied generally to
various forms of boiler; all that is needed being to vary the forms of flues or
passages through which the products of combustion pass. Also the heat passing
through the combustion chamber may be utilised to impart heat to the entering air.
I shew in Fig. 7 a construction of this kind applied to a combustion chamber of
form somewhat different from that shewn in Fig. 6, but equally applicable to the
latter. In Fig. 7 A. is the slide or valve which regulates the admission of the air.
The air admitted through it enters the casing b, and passes thence through the
passage e in which it receives heat through D, the material surrounding the com-
bustion chamber C. From e the air passes to meet the mixed fluid issuing from the
orifice ; t is an orifice for inserting a kindling flame and for inspection. The
construction is shewn in Fig. 7 as applied to a flat-bottomed boiler, but, like the
constructions previously described, it is applicable when the heat is employed for
other purposes. The fire-brick or other material used for the construction of the
combustion chambers may be built up of numerous pieces, according to any of the
known methods of construction.
When the heat is applied to the heating of boilers a combustion chamber of fire-
brick or like material may be dispensed with, but generally I prefer to employ it.
One advantage resulting from its use is that the heat of the chamber serves to re-
kindle the flame in case of its extinction.
In the various forms of burner or mixing apparatus above described, it is not
absolutely necessary to take in a second supply of air, they are capable of being
used without this; but I consider it preferable to take in the second supply of air,
one advantage of this being that the top of the burner is kept cool, and another
that there is less risk of the flame striking back. Also in all the forms of burner
above described instead of drawing in the air by means of the jet of gas, the gas
and air may both be forced by means of a blower or forcing apparatus; or the air
may be forced by such an apparatus and the gas drawn in by it.
When it is desired to produce intense heat oxygen may be used instead of air.
By the use of oxygen a heat may be produced greater than the walls of any furnace
are capable of resisting. When it is desired to operate with such a heat an arrange-
ment may be used like that shewn in Fig. 8. Here A is a basin formed of lime, in
the cavity of which the material B which it is desired to subject to heat is placed ;

page_text: C, C, are chambers into which a mixture of oxygen and combustible gas is forced in
suitable proportions by a pump or forcing apparatus; O is a chamber into which
oxygen is forced in like manner.
The relative position of the oxygen and the mixture may obviously be inverted;
o, o, i, i, are annular passages which may be formed in refractory material or may
pass through a water casing. The oxygen issues in an annular jet, and on either side
of it the mixture of oxygen and combustible gas issues in an annular jet, directed so
as to impinge upon the central jet of oxygen. The stream of products of combustion
strikes down on the material placed in the cavity of the lime. The products of
combustion acting in the basin A rise to the flue H, mixing as they rise with a
sufficient quantity of air to reduce their temperature.
In employing this apparatus, in order to obtain still greater intensity of heat, the
gas which is used unmixed, whether this be oxygen or the gas which is burnt with
it, may be supplied in a heated state. In this case I prefer that this heated gas
should issue through nozzles or passages formed in refractory material which is a
slow conductor of heat, while the mixed gases pass through passages kept cool by
water jacketing in order to prevent the flame from striking back.
Having thus described the nature of my Invention and in what manner the same
is to be performed, I claim in respect of gas burners:-
First. The combination of an annular gas jet with a mixing passage of varying
sectional area, substantially as herein described with reference to Figs. 4 and 4b of
the accompanying Drawings.
Second. Admitting a regulated supply of air to both the interior and the exterior
of an annular jet of mixed gas and air, substantially as herein described with
reference to Figs. 4 and 5 of the accompanying Drawings.
Third the modified construction of burner of the kind referred to in the preceding
claim, wherein the air and gas supply orifices are governed by connected valves,
substantially as herein described with reference to Fig. 6 of the accompanying
Drawings.
In witness whereof, I, the said Matthew Piers Watt Boulton, have hereunto
set my hand and seal, this Twenty-eighth day of July, in the year of our
Lord One thousand eight hundred and seventy-seven.
M. P. W. BOULTON. (L.S.)