Improvements in or relating to Gas Stoves
Year: 1896

page_text: Date of Application, 16th June, 1896-Accepted, 19th Dec., 1896
Improvements in or relating to Gas Stoves
A communication from A. WUNDERLICH, of 35 Rue Henri Maus, 35, Brussels,
in the Kingdom of Belgium, Civil Engineer.
I, ALFRED JULIUS BOULT of 111 Hatton Garden, in the County of Middlesex,
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 gas stoves or heaters.
In the accompanying drawings
Fig. 1 represents the whole of the stove in vertical section,
Fig. 2 shows it in sectional plan on the line of Fig. 1 and
Figs. 3 to 13 give details of the arrangement of the two modifications of Bunsen
burner employed in the stove and hereinafter fully described.
With reference first to Figs. 1 and 2 the stove comprises the following chief
parts :-
1. A Bunsen burner A B B' arranged in the interior of a tube L and outside a
concentric tube M, that is to say in an intermediate annular space J 3 forming a.
chamber for mixing gas and air.
This mixing chamber J 3 has at the top two conical tubes N' M¹ forming a
conical annulus J 4 serving as an orifice for the escape of the gaseous mixture,
which escapes through a metallic net J 5 forming a cylindrical shell, the axis of
which is the same as that of the mixing chamber J 3.
2. A bottom plate B 2 having holes b4 and 65 for the admission of air into the
body or cylindrical shell G 2 of the stove; on the plate B 2 are mounted movable
circular covers, an external one D2 and an internal one E 2. The external
cover D 2 is perforated with holes d 2 corresponding to the holes 64 and the inner
cover E 2 has holes e 2 corresponding to holes b5.
To regulate the relative positions of the holes d2 and 64, the cover D2 is
turned by means of a handle d 6, the spindle d5 of which is fixed in a projection d4;
to regulate the relative position of holes c2 and 65, the cover E 2 is turned by
means of a handle c6, the spindle of which is secured in the projection or boss c4
on the said plate. The plate D 2 is held on the bottom plate B 2 by means of a
bolt and nut c 3.
To make the bottom plate B 2 sufficiently strong for supporting the inner body
of the stove, it is provided with radial ribs b6 (Fig. 2).
The bottom plate B 2 is supported by a bed F 2 suitably arranged and provided
with holes or openings f2 for admitting air underneath the stove from where it
rises through the holes in the movable circular covers D2 and E 2.
3. A jacket or shell G 2 constituting the body of the stove and comprising a
door with a transparent plate g 2, the dome L 2 with a chimney i2, the cover H 2
and a tube g3 for the escape of combustion gases. The jacket G 2 has no opening.
through which air could penetrate, unlike the gas heaters or stoves as used
hitherto.
4. A heat-regenerator consisting of a tube 04 of refractory material closed at
the top by a cap 03 and containing in its interior a continuation of the central
tube M through which the air ascends from the bottom of the stove to the top,.
that is to say from the bottom plate B 2 to the cap O 3.

page_text: aire entering at the bottom of the regenerative tube O4 passes through the
funnel shaped space formed between O 4 and M' and escapes in the direction of
the arrows K 5 meeting, when coming out through the metallic net surrounding
the circular edges of the parts 04 M N, with the gaseous mixture escaping
in the direction of the arrows J 5.
The regenerative refractory tube is supported at the outside by a ring connected
to the jacket G 2 of the stove by the arms Q'.
The concentric position of the regenerative tube O 4 and of the suction tube M
is maintained by a ring R' with radial arms, which encircles the upper end of the
tube M.
A guide-plate M 2 may be inserted as shown between the parts M' and O4 to
facilitate the flow of air into the place where it meets the gaseous mixture.
When the stove is lighted, the gas and the air for feeding the flame as well as
the air used for being mixed with the gas before being lighted take the directions
indicated by the different arrows as follows:-
The gas from the gas pipe enters at A 1, (Fig. 1) passes through the branches B,
enters into the burner, the special construction of which will be hereinafter
described for two different modifications, passes out of it in the shape of very fine
jets indicated by the arrows F and H and rises into the mixing chamber following
the direction of the arrows J 3. The rising of the gas induces a draught of air
through the openings or holes e 2°65 and causes said air to pass through the
passages J and to ascend through the chambers J 2 till it gets mixed at J 3 with
the gas in order to produce a perfect gaseous mixture which afterwards proceeds
in the direction of the arrows J 4 and J 5.
At the same time, some air is made to enter through the tube M. This air goes
to the regenerative tube 04 as already described and meets at K 5 the ascending
current of the lighted gaseous mixture and oxydises it completely giving to it at
the same time additional heat which the surrounding feed-air, that is to say, the
external air coming directly from the bottom along the walls of the tubes L and N
has taken away during the ascent, in getting heated.
That new arrangement which cannot be found in any hitherto known heating
apparatus forms, together with the special construction of the burner, the main
part of the object of the present application and permits the realisation of the
perfect combustion of any gas, even if it be very rich in carbon or acetylene and
consequently necessitates a great volume of air relatively to the volume of gas and
to the development or volume of flames.
A second important point for the safe use of gas stoves in offices and rooms is
that neither the feed-air for the flame nor the air co-operating with the gaseous
mixture is forced to follow sinnous paths or paths closed by deflectors, whereas in
most of the constructions used hitherto the air is led through different obstacles
in order to make its current as slow as possible and to increase the heating surface
or regenerate the heat. Only the current of air ascending through the central
tube M into the interior of the regenerative tube and entering from the interior
into the flames has to follow a certain direction when rising and descending again
into the regenerator 04.
Therefore no condensation in consequence of expansion of the air or gaseous
mixture-not perfectly burned-can take place and no deposits of carbon can be
formed also all danger of explosion or of the formation of mixtures liable to
produce explosions is excluded.
On the other hand the arrangements of the jacketted stove and of the dome are
made so as to realise in combination with the refractory body or accumulator of
heat of the regenerator, the same conditions of radiation of heat as exist in a coal
or coke stove of the same external shape.
The arrangement of the bottom plate B 2 in combination with the annular
cover D2 and circular cover E2 has the great advantage that the air is admitted
in the axial direction uniformly distributed all round the axis of the burner and of
the regenerater and of that all adjusting is reduced to the handling of two

page_text: handles d 6 and c6 one of which regulates the supply of feeding air and the other
the supply of air for mixing and regenerating.
There is no regulating or closing device at the pipe or chimney for the escape
of combustion gases, the result of which is that in no case could there be the
slightest escape of gas through the bottom of the store.
The burning of the stove is controlled simply by looking through the door g 2
closed by a transparent plate of mica or other suitable material.
The mechanical construction of the different parts of the stove and the way they
are put together allows of their free expansion or contraction when the stove is
lighted or extinguished as well as of the easy replacing of the only part subject to
wearing out, that is to say the regenerative tabe, which is simply suspended. In
consequence of that the latter can be made incandescent in order to produce a
maximum regenerative effect without any inconvenience.
According to the intensity of heat which the stove or heating apparatus has to
develop or according to the size to be used for attaining a certain heat effect,
one of two typical forms of construction hereinafter described, of Bunsen burner
is chosen.
The first construction, for large sizes, is represented in Figs. 3 to 9 of the
accompanying drawings, which will now be described :-
Fig. 3 shows a section through the tube L N and the bottom plate B 2, showing
in this way the general arrangement of the burner placed in the space of those
parts.
Fig. 4 is a plan of the whole burner, and
Figs. 5 to 9 are details of construction of its nozzles. The gas arrives by the
pipe A', branches off at A into two passages B and enters into a gas-chamber
constituted by a circular annular box B₁ closed at the top on all its annular surface
except in places where the nozzles B3 are arranged, these nozzles being secured in
vertical holes made in the upper part of the box B. The nozzles B 3 are made
taper towards their upper ends and are closed by an inverted inner cone B 4
(Fig. 6) provided with a central axial perforation G6 (Figs. 6, 7, 8 and 9) and
two recesses or grooves G 4 and G 5 made on its circumference and inclined to the
axis of the nozzle. The inclination of one of the grooves G4 is in the opposite
direction to that of the other groove G 5 so that when the jets of gas come out of
the passages formed by the grooves with the interior cylindrical surface of the
nozzle B 3, they produce a rotation of the column of air sucked in and taken by
these jets of gas.
The special arrangement of the two grooves G4 and G 5 and of the central
Fole G 6 is quite clear from Figs. 5 to 9 of the accompanying drawings. Fig. 6 is
a section through the axis of one of the nozzles B 3 such as are screwed or
otherwise placed on the cover or upper part of the gas chamber B'; the inverted
cone B 4 is also shown in section and in such position that the three orifices are
indicated by parallel lines. Fig. 8 is an elevation of the same cone in a position
turned through an angle of 90° from that in which it is shown by Fig. 6.
Fig. 5 is a view of the cone looking from the bottom whilst it is in a corre-
sponding position to that in which it is shown in Fig. 6, and Fig. 7 is the same
view from the top; Fig. 9 on the contrary shows the cone B 4 in horizontal section
on line y y of Fig. 8.
Another peculiarity of the arrangement of nozzles B 3 according to the present
invention consists in that for an arrangement with, say, eight nozzles, as in Fig. 4
the groove G 4 in a cone B 4 receives such an inclination that the direction of gas
jet is to the left, whereas the inclination of the groove G 4 in the next nozzle is
such that the direction of the gas jet is to the right, and so on alternately, so that
in half of the nozzles the jets G4 are to the right of the axis whereas in the
other half they are directed to the left of the axis; the same is done with the
corresponding grooves G 5.
Thus is obtained rotation of columns of air sucked in in the direction of the
arrows indicated in Fig. 4, which rotation exercises an influence in taking up of

page_text: the whole surrounding air, contained in and ascending into the mixing chamber, so
that the most perfect and thorough mixing possible is attained. According to the
nature of the gas and to the relative dimensions of the different parts and organs
of the present burner, air passages can also be obtained by making in the internal
and external cylindrical surface of the annular cover B 5 straight grooves J 9 J 10
in the direction of the axis or inclined. In the burner of such construction, the air
entering through the holes b5 of the bottom plate B2 ascends on one side in the
direction of the arrows K and enters into the interior of the tube M and on the
other side ascends in the direction shown by the arrows and passes over the cover B 5
into the mixing chamber J3 where in consequence of the strong whirling
movement of different columns of air, each of which is rotating, a perfect mixing of
particles of air and of gas takes place, such as it has been impossible to realise
hitherto,
Instead of notches J 9 and J 10 made in the cover B 5, it may also be provided
with holes on the whole of its surface or cousist of one or several metallic
nets.
The second construction of Bunsen burner is represented in Figs. 10 to 13.
Fig. 10 is a longitudinal section thereof and Fig. 11 a horizontal section on the
line X-X of Fig. 10.
Figs. 12 and 13 show details of the construction of the gas-chambers with
notches or passages for the escape of jets of gases in an inclined direction.
The gas arrives through the tube A, follows the branches B and enters into the
first annular gas-chamber C; from that chamber the gas escapes on one side
through a series of fine openings G, arranged or made in the covering ring R; on
the other side the gas passes into the second annular gas-chamber E through the
branches or connections D, from which it also escapes through fine openings F
made in the covering ring Q. The two gas-chambers C and E are concentric and
arranged so as to leave an empty annular space J between the outer walls, through
which space the air can freely pass and enter into the Bunsen burner. This
space J constitutes an intermediary air-suction way. Another (outer) air suction
is provided round the circular external wall S of the gas-chamber C, and a third
(inner) air suction occurs by way of the tube M of the gas chamber E.
This third air suction does not influence any more than it did in the preceding
construction, the mixture of gas and air, but only the draught or the supply of
fresh air to the flame of the burner or to the regenerator.
The ascending movement of gas is respectively shown by arrows F and G and
the upward movement of air by the arrows H J K. In order to obtain with the
present arrangement as perfect and close a mixture of gas and air as is necessary
for perfect and absolute combustion of gas, even when gases such as acetylene or
others are used, a special arrangement of holes has been made, through which the
gas jets escape from the covering rings R and Q inserted.
In order to make the nature of this part of the invention better understood, each
of the gas-chambers is represented separately in Figs. 12 and 13, the covering
rings Qand R being shown in elevation and the outer walls of the gas-chambers in
section.
By examining these figures it will be seen that in one of these rings (Q) the
openings (F) for the escape of the gas have such a helicoidal inclination, that the
gas jets are directed at their outlet to the right, whereas the openings G for
the escape of the gas have such a helicoidal inclination that the escaping gas-jets
are directed to the left; the result is that the ascending column of air from D
receives from the gas-jets F a rotary motion towards the right and the ascending
column from H receives from the gas-jets G a rotary movement to the left.
The two columns of air and gas, of annular shape, under. the influence of the
impulse of forces acting in opposite directions, of course rub against each other at
their points of contact and consequently produce division and whirling of particles
of the gaseous mixture, the result of which is to produce in the most advantageous
manner such a thorough mixing in all the layers of the fluid ascending in the tube

page_text: of the Bunsen burner, as has been hitherto impossible to attain. The jeta F and G
can however have the same directions and then the passages whence they issue
will receive a different inclination which also will result in a rotary or mixing
motion.
The shape of the walls P and T of the gas-chambers C and E is chosen such as
to facilitate the suction of the intermediate column of air through D, as is also
shown for the wall S in order to facilitate the suction of the external column of
air K.
Finally it must be mentioned that the heating devices hereinbefore described
and illustrated in the accompanying drawings may be advantageously used for
industrial and domestic purposes in offices and apartments and among other
uses, for heating thermo-electric batteries in which they will acquire especial
importance.
Having now particularly described and ascertained the nature of the said inven-
tion as communicated to me by my foreign correspondent I declare that what [
claim is ;-
In gas stoves and gas-heating apparatus of any kind and for any industrial
application the use of
1. The arrangement of a Bunsen burner in such a manner that when the burner
is lighted there are two separate air suctions one of which the external one supplies
air to the mixing chamber whereas the other the internal one supplies air to the
regenerative chamber arranged on the top of the mixing chamber.
2. The arrangement of a bottom plate carrying the outer shell or casing and the
whole of the Bunsen burner characterised in Claim 1 and having two different
series of holes corresponding to similar series of boles in movable covers mounted.
on said bottom plate in such manner that simply by operating two handles the
admission of air either into the chamber for external feed of the flame or into the
chamber for gaseous mixture and into the regenerative chamber may be regulated.
independently of each other.
3. The arrangement of a dome with axial chimney for the escape of the
combustion gases ahove the regenerator in combination with a shell constituting an
airtight jacket and resting on the bottom plate characterised in Claim 2 in such
manner that the upward and downward draught of the gas air and gaseous mixture
is uniformly distributed round the centre or vertical axis of said jacket.
4. The arrangement of a regenerative chamber constituted simply by a tube
placed above the mixing chamber and made of refractory material' closed at the
top and open at the bottom so that the air entering into it from a pipe or tube
arranged in the centre of the mixing chamber gets heated by the beat emitted by
the interior of the flame and enters into a circular cylindrical or conical space
directly above the space corresponding to the place where the flame is originated
so that the quantities of beat which this air brings from the interior to the flame
compensate for the quantities of heat which the air introduced to the flame from
the exterior takes away in getting heated.
5. A construction of the Bunsen burner characterised by the arrangement of any
even number of nozzles (B3) in the upper part of an annular box B¹ constituting
the gas chamber in such a manner that distinct jets of gas in any number escape
from each of the nozzles B 3 in an axial or in an inclined direction causing thereby
the air to be sucked into the annular spaces surrounding and also encircled by the
box B and to pass through holes provided over and around the mouths (B4) of
the nozzles B 3 and made in an annular cover B 5 separating the upper chamber in
which the mixing takes place from the lower chamber in which the suction takes
place the two chambers heing comprised between the outer tubes L N and the
concentric central tube M.
6. The combination of the arrangements of the stove characterised in Claims 1
to 4 with the construction of Bunsen burner characterised by the arrangement of
grooves or notches made in a cone B4 placed in the interior of the cylindrical

page_text: opening of the nozzles B 3 in such a manner that the gas escapes from each of the
latter in a central jet in the axial direction (see G 6) and in one or more side jets
(see G 4 and G 5) the direction of which may be axial or inclined to the axis.
7. The combination of devices characterised in Claim 6 with the arrangement of
lateral gas-jets-G 4 and G 5-in such manner that in one nozzle the inclination of
corresponding jets-G 4 and G 5-of the neighbouring nozzles is such that if
in one nozzle the gas jets communicate to the ascending air column a rotary
movement towards the left the gas jets of the neighbouring nozzles on the right
and left hand sides produce a rotary movement of the air column towards the
right.
8. The combination of the arrangements or devices of a stove characterised in
Claims 1 to 4 with another form of construction of Bunsen burner characterised by
the use of two distinct gas chambers C and E having the shape of annular boxes
and separated from each other by an intermediate space D permitting an inter-
mediate air draught J to be utilised between two gas-jets G and F arranged
between an external draught of air H and an internal draught of air K.
9. The combination of arrangements characterised in preceding claims with a
special arrangement of orifices or holes for the escape of gas jets F and G in the
covering rings Q and R inserted into the annular boxes constituting the gas
chambers C and E which arrangement is characterised by an inclination of the
direction of gas jets relatively to the axis of the burner that inclination being
either in the same direction under the same angle or under different angles in each
covering ring and R or in an opposite direction to each other as represented in
Figures 12 and 13 of the accompanying drawings in order to communicate rotary
movement to the ascending air and thus to attain thorough mixing of air
and gas.
10. The combination and arran nent of parts constituting a complete gas-stove
substantially as and for the purpos, lescribed and illustrated in the accompanying
drawings.
Dated this 15th day of June 1896
BOULT & WADE,
Agents for the Applicant.