Improvements in Gas Stoves.
Year: 1896

page_text: Date of Application, 6th Oct., 1896-Accepted, 21st Nov., 1896
Communicated from abroad by VIRGIL WARREN BLANCHARD, of New York,
and EDWARD KENYON STOW, of Fenhurst, Long Island, New York, United
States of America.]
Improvements in Gas Stoves.
I, OLIVER IMRAY, of No. 28 Southampton Buildings, Chancery Lane, in
the County of London, Chartered Patent Agent, 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 relates to a gas stove or apparatus for producing heat by
combustion of gas.
Its object is to effect perfect combustion by consuming with gas large volumes
of air which is heated in the apparatus before its admixture with the gas, and is
introduced into the burning gaseous mixture in small quantities at successive
points, as I shall describe referring to the accompanying drawings.
Fig. 1 illustrates the apparatus especially adapted for heating stoves, by
combustion of illuminating gas.
Fig. 2 illustrates a form of the apparatus especially adapted for burning
producer or water gas.
Fig. 3 illustrates means of mingling the gas with air before or after its ignition,
but before it enters the combustion chambers of the apparatus.
Figs. 4 and 5 are details.
A, B, C, designate three pan-shaped casings, placed one within the other and
separated by air spaces 1, 2, which communicate over the edge of pan C, under
the cover D, which fits on both pans A, C, and has a central opening D'.
Pan A has a central opening in its bottom fitted on the upper end of a cylinder E,
within which is a burner F.
A tube G is fitted in openings in the bottoms of the pans B, C, directly above
the burner F, so as to conduct flame from the burner into a dome H, placed in the
cup B over the tube G, and forming a pocket to retard combustion gases.
The dome has gas exit passages H' in its lower edge, above which, on the outer
side of the dome, is a lateral flange H2, that extends nearly to the sides of the
cup B, so as to direct the heated products of combustion against the sides of the
pan B.
In Fig. 1 the dome H has a central concavity h in its ceiling surrounded by
shallow annular concavities h¹ for the purpose of retarding the lighter gases.
The flange H is also slightly concaved for the same purpose.
In Fig. 2 the dome H has a larger concavity from which a number of
studs project downwards and the flange H2 is also provided with a number of
studs h.
In Fig. 2 an inwardly projecting flange I is placed in the cup B above the
flange H, and also a second flange i.
The flanges I and i may have projecting studs I' and .
Stude 12 may proiect unwards from the top of the dome H.

page_text: The cup B has a number of concentric perforations b, in its bottom through
which air is admitted into the dome; it also has concentric perforations 1, 63, 6³,
through which air is admitted to mix with the gases passing under the flange H.
In Fig. 2 the pan B has additional series of perforations 6, 6 through its sides
admitting air to mix with the gases rising between the flanges.
The lower end of the cylinder E is closed by a plate J, through the centre of
which is a pipe-joint j on the inner end of which is a screw cap in which is
screwed the lower end of an upright pipe having a burner F on its upper end,
and in its lower end a gas-jet f.
Openings in the pipe f admit air to mingle with the gas before its ignition.
The joint is connected by an elbow to a valved gas supply pipe.
A rotating valve K is fitted below the plate J, to regulate the supply of air.
The gas
can be lighted at the burner F through an opening E' of the cylinder E
which is closed by a ring valve E³.
The plate J has a projecting T-shaped flange J, to which the legs k and arms K¹
for supporting a foot rest are secured by means of clips K³ and bolts and
nuts K
Fig. 4 shews the arrangement of the studs on the flanges; and Fig. 5 shews
this arrangement in the dome H (Fig. 2).
In Fig. 3 is shewn a series of gas and air mingling taper tubes L arranged one
above the other within the cylinder E.above the burner F.
Two or more such tubes may be employed if desired. By this arrangement of
taper tubes a gaseous current under pressure entering the lowest tube and
traversing them successively, causes portions of the air in the cylinder E to enter
at the points where one tube discharges into the other. The tubes are gradually
increased in size, from below upwards.
When the gas is very rich in carbon, it may be desirable to pass it through
tubes L.
The apparatus operates as follows:-
Gas flowing through the the tube f is mixed with air and the mixture is fired
at the burner F.
The heated products then pass through the tube G into the dome H, drawing up
air through the cylinder E, part of the air eutering the tube G with the gases and
part flowing into the air passages 1 and 2 to be heated.
As the gases descend in the dome outside the tube G they are mixed with jets of
hot air entering through the perforations b, and as they pass in a thin layer
outwards from the dome under the flange H2 they are successively mixed with
jets of air through perforations b',.6, 63, so that the combustible portions are
burned.
The thin layer of burning gases after passing outwards under the flange H 2 and
becoming commingled with the jets of highly heated air, which increase the
temperature of the layer, is directed against the wall of the pan B, thereby raising
to a very high temperature the current of air descending the space 2 and rendering
it fit to act effectively in promoting combustion. When the flanges I, i, are
employed, the gases are subjected to additional jets of heated air through the
perforations 6, 6, (Fig. 2).
By the arrangements described the process of combustion is progressive in
character, small volumes of heated air being added to the burning gases in minute
jets at intervals, and heat developed by their combustion before another addition
of air. The cooling of the combustible gases is thus avoided and their temperature
is constantly increased.
The apparatus is so designed that the currents of burning gases and heated air
are constantly changing or reversing their direction of movement, and expanded
and contracted, distributed and commingled, so that the whole internal structure is
raised to an intensely heated condition and combustion is so complete that no
odours are produced. In practice, from thirty to fifty cubic feet of air can be
mingled and consumed with one cubic foot of gas, while the dome and internal

page_text: parts are maintained at such a high temperature that complete combustion of the
gaseous elements is realised, there being always a supply of oxygen present in the
burning gases to effect combustion of their combustible ingredients.
The dome being externally surrounded by highly heated products of combustion
radiation of heat from it is prevented and consequently its temperature is raised to
a degree that ensures realisation of the desired results.
As a result of the intense temperature realised in the concavity of the dome H,
and in the space around it disassociation of the water vapour held in solution by
the air supplied into oxygen and hydrogen is effected their combustion adding to
the heat production.
By the apparatus described approximately perfect conversion of combustible
fluids into heat is realised, without the presence of smoke, or noxious odours; and
the theoretical value in heat units of the gas is approximately realised in
practice.
Scientific tests have demonstrated that seven cubic feet of illuminating gas of
average quality burned in the apparatus described give the same number of units
of heat in the same time as thirty cubic feet of gas of the same quality burned in
an ordinary gas stove.
If the pans B, C, were removed and the dome placed direct upon the casing A,
which could then be perforated to admit air, a good heating apparatus would be
produced, but not equal to the complete apparatus.
The studs I and and 12 facilitate the mixing of the combustible fluid with
the air.
Under certain circumstances there may be perforations G through the wall of
the tube G as shewn in Fig. 2 for the admission of jets of air into the burning
gases as they descend in the space between the tube G and the wall of the dome H.
In that case a less number of perforations in the bottom of the pan C would he
required.
In Fig. 2 a removable ring G 3 is shewn in tube G to regulate the amount of
air rising through the tube. The size of this ring can be varied to suit the quality
of gas employed.
As shewn in Fig. 2 the burning gases rise from the burner F in a column which
strikes the ceiling of the dome H there being ample space around the column in
the tube G for ascent of air.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A gas stove constructed and operating substantially as described with reference
to Fig. 1.
2. In combination with the internal chambers of the stove above referred to,
flanges and studs such as are shewn in Fig. 2 substantially as and for the purpose
set forth.
3. In combination with the stove above referred to, a series of taper tubes
one above the other as shewn in Fig. 3, as and for the purpose set forth.
4. In a gas stove the combination of a combustion chamber, an air chamber
exterior thereto, and a dome in the combustion chamber having an external flange
over parts for the escape of burning gases from the dome in a thin layer directed
against the walls of the combustion chamber; with means for admitting air from
the air chamber into the burning gases, substantially as and for the purpose
described.
5. The combination of the cylinder, the casing thereon having air passages
around its walls and an internal combustion chamber; with a gas and air mixing
tube and burner in the cylinder a tube over the burner, extending into the
cuinbustion chamber, a dome over the tube within the combustion chamber
having ports in its lower edge, and apertures for admitting air from the air

page_text: passages into the burning gases in the dome and combustion chamber, substantially
as described.
Johor 1906
ABEL & IMRAY,
Agents for the Applicant.