IMPROVE- MENTS IN STEAM COOKING APPARATUS
Year: 1877

page_text: LETTERS PATENT to Gerard Wenzeslaus von Nawrocki, of the Firm of J.
Brandt and G. W. von Nawrocki, Civil Engineers and Patent Agents, of No. 2,
Koch Strasse, Berlin, in the German Empire, for the Invention of "IMPROVE-
MENTS IN STEAM COOKING APPARATUS." A communication by Johanu Andreas
Kumberg, of Baden-Baden, in the German Empire.
Sealed the 7th August 1877, and dated the 19th March 1877.
PROVISIONAL SPECIFICATION left by the said Gerard Wenzeslaus von
Nawrocki at the Office of the Commissioners of Patents on the 19th March
1877.
GERARD WENZESLAUS VON NAWROCKI, of the Firm of J. Brandt and G. W. von
Nawrocki, Civil Engineers and Patent Agents, of No. 2, Koch Strasse, Berlin, in
the German Empire. "IMPROVEMENTS IN STEAM COOKING APPARATUS." A. com-
munication by Johann Andreas Kumberg, of Baden-Baden, in the German
Empire.
This Invention has reference to an improved construction of steam cooking
apparatus, whereby the meat or other food to be cooked is first subjected for a
certain time to the action of steam from quietly boiling water, after which the
cooking operation is completed by subjecting the food to the action of the heavier
or more saturated steam from violently boiling water, or to the action of the water
itself. By this improved mode of operating the cooking is effected much more
rapidly and effectually than heretofore, while by the construction of the apparatus a
considerable economy of fuel is effected as compared with the ordinary process of
boiling with water.
For the above purpose, according to one arrangement adapted for household use,
a closed sheet-metal receptacle filled with water, and constituting a boiler, contains
centrally within it a vertical cylindrical chamber extending from top to bottom of the
boiler. At the upper end the chamber is open to the atmosphere, and at the lower
end it is conically enlarged, and is closed at bottom by a grate level with the
bottom of the boiler, the conical enlargement constituting the fire-box, into which

page_text: fuel, by preference charcoal, is introduced through a tube or hopper passing down
through the chamber, and of such a size as to leave a certain space between it and
the chamber on one side only, such space serving as a chimney or flue to the fire-
box. The fuel hopper is closed at the top by a cover, and a pipe leads down from
the space above the fuel into the fire-box, so that any volatile constituents of the
fuel that rise to the top of the hopper are conducted down through the said tube,
and are passed through the fire and burnt before they can escape up the chimney
flue. Surrounding the fire-box is a chamber, communicating with the water space
of the boiler through a hole on one side, while at the other side it has a pipe
ascending to above the water level of the boiler, and terminating in a bend. Near
this pipe is a second pipe leading down from above the water space of the boiler,
and passing out through the side of the latter, its projecting end being temporarily
connected to a branch pipe leading into a closed vessel in which is placed the meat
to be cooked. The upper end of the second pipe terminates in a branch that can
either be turned so that it is in close communication with the bend of the first-
named pipe, so as to cause the steam rising through the latter to pass direct into the
former, and thence into the cooking vessel, or the branch can be turned away from
the bend, so that steam from the steam space of the boiler passes through the pipo
to the cooking vessel. The general water space of the boiler being shielded from
direct contact with the sides of the fire-box by the before-mentioned water chamber,
the water in the latter will boil much more violently than that in the former, and
consequently it will be seen that when the said branch of the pipe leading to the
cooking vessel is turned, as last described, steain suitable for the commencement of
the .cooking operation will pass through it, while when the brauch is turned as first
described the saturated steam from the violently boiling water in the water chamber
is conducted to the meat. A second escape pipe is provided in the boiler leading
down from above the water space, and passing through the side of the boiler for con-
ducting steam to other cooking apparatus, such pipe being closed by a valve at its
upper end when not required. Below the fire-grate of the boiler is a shallow ash-pit
having holes for supplying air to the fire, and below the ash-pit is constructed an
oven for baking articles of food by the heat radiated down from the fire-box. If
charcoal be used as fuel the fuel chamber may be left open at top, as described, for
the escape of the products of combustion, and it only closed with a cover when it is
desired to extinguish the fire; or when other fuel is used the chamber may be kept
permanently closed, and a flue pipe be led from its upper end into a chimney. The
boiler is also provided with one or more cocks for withdrawing hot water when
required.
.
According to another arrangement of the apparatus suitable for camp purposes, a
wrought-iron vessel is divided by a partition into an upper and lower compartment,
the lower one serving as a fire-box, and the upper one constituting the boiler,
through which at one side a vertical cylinder constituting the fuel hopper descends into
the fire-box. Both the boiler and fuel hopper are open at top, and on to their open
ends are fitted extensions, which can slide telescopically thereon, so that when the
apparatus is not in use the extension can be slid downwards upon the casing, so as
to occupy less room; these extensions are closed at top by covers. In the extension
of the boiler is a horizontal perforated diaphragm, which, when the extension is in
the raised position, is situated a short distance above the water level of the boiler,
and upon it is placed the meat to be cooked. The diaphragm is supported on pivots,
and can be turned by means of a lever outside from the horizontal into an inclined
position, so that the meat after having been subjected to the action of the steam
for a certain length of time is caused by the tilting of the diaphragm to fall into
the water of the boiler to complete the cooking operation.
The apparatus is provided with a detached stand, consisting of a closed metal
receptacle, which can be filled with water heated by the bottom of the fire-box to
be used for any purpose, the stand being made of such a size that when the
apparatus is not in use it can be placed inside the boiler, so as to economise space.
Where there is a camp fire available the separate heating of the boiler may be dis-

page_text: pensed with, the boiler being placed on the camp fire. In this case the space inside
the fuel hopper may be utilised by placing therein a cylindrical vessel in which
coffee, tea, or other drinks may be heated.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Gerard Wenzeslaus von Nawrocki in the Great Seal Patent Office on
the 13th September 1877.
GERARD WENZESLAUS VON NAWROCKI, of the Firm of J. Brandt and G. W. von.
Nawrocki, Civil Engineers and Patent Agents, of No. 2, Koch Strasse, Berlin, in
the German Empire. "IMPROVEMENTS IN STEAM COOKING APPARATUS." A com-
munication by F. A. Kumberg, of Baden-Baden, in the German Empire.
This Invention has reference to an improved construction of steam cooking
apparatus, whereby the meat or other food to be cooked is first subjected for a
certain time to the action of steam from quietly boiling water, after which the
cooking operation is completed by subjecting the food to the action of the heavier
or more saturated steam from violently boiling water, or to the action of the water
itself. By this improved mode of operating the cooking is effected much more
rapidly and effectually than heretofore, while by the construction of the apparatus
a considerable economy of fuel is effected as compared with the ordinary process of
boiling with water.
For the above purpose, according to one arrangement adapted for household uso,
a closed sheet metal receptacle filled with water, and constituting a boiler, contains
centrally within it a vertical cylindrical chamber extending from top to bottom of the
boiler. At tho upper end the chamber is open to the atmosphere, and at the lower
end it is conically enlarged, and is closed at bottom by a grate level with the
bottom of the boiler, the conical enlargement constituting the fire-box into which
fuel, by preference charcoal, is introduced through a tube or hopper passing down
through the chamber, and of such a size as to leave a certain space between it and
the chamber on one side only, such space serving as the chimney or flue to the fire-
box. The fuel hopper is closed at the top by a cover, and a pipe leads down from
the space above the fuel into the fire-box, so that any volatile constituents of the
fuel that rise to the top of the hopper are conducted down through the said tube,
and are passed through the fire and burnt before they can escape up the chimney
flue. Surrounding the fire-box is a chamber communicating with the water space
of the boiler through a hole on one side, while at the other side it has a pipe
ascending to above the water level of the boiler, and terminating in a bend. Near
this pipe is a second pipe leading down from above the water space of the boiler,
and passing out through the side of the latter, its projecting end being temporarily
connected to a branch pipe leading into a closed vessel, in which is placed the incat
to be cooked. The upper end of the second pipe terminates in a branch that can
either be turned so that it is in close communication with the bend of the first-
named pipe, so as to cause the steam rising through the latter to pass direct into the
former, and thence into the cooking vessel, or the branch can be turned away from.
the bend, so that steam from the steam space of the boiler passes through the pipe
to the cooking vessel. The general water space of the boiler being shielded from
direct contact with the sides of the fire-box by the before-mentioned water chamber,
the water in the latter will boil much more violently than that in the former, and
consequently it will be seen that when the said branch of the pipe leading to the
cooking vessel is turned, as last described, steam suitable for the commencement of
the cooking operation will pass through it, while when the branch is turned, as first
described, the saturated steam from the violently boiling water in the water chamber
is conducted to the meat. A second escape pipe is provided in the boiler leading

page_text: down from above the water space, and passing through the side of the boiler for
conducting steam to other cooking apparatus, such pipe being closed by a valve
at its upper end when not required. Below the fire-grate of the boiler is a shallow
ash-pit having holes for supplying air to the fire, and below the ash-pit is constructed
an oven for baking articles of food by the heat radiated down from the fire-box.
If charcoal be used as fuel the fuel chamber may be left open at top, as described,
for the free escape of the products of combustion, and it is only closed with a cover
when it is desired to extinguish the fire; or when other fuel is used the chamber
may be kept permanently closed, and a flue pipe be led from its upper end into a
chimney. The boiler is also provided with one or more cocks for withdrawing
hot water when required.
According to another arrangement of the apparatus suitable for camp purposes, a
wrought-iron vessel is divided by a partition into an upper and lower compartment,
the lower one serving as a fire-box, and the upper one constituting the boiler,
through which at one side a vertical cylinder constituting the fuel hopper descends
into the fire-box. Both the boiler and the fuel hopper are open at top, and on to
their open ends are fitted extensions which can slide telescopically thereon, so that
when the apparatus is not in use the extension can be slid downwards upon the
casing, so as to occupy less room; these extensions are closed at top by covers.
In the extension of the boiler is a horizontal perforated diaphragm, which, when
the extension is in the raised position, is situated a short distance above the water
level of the boiler, and upon it is placed the meat to be cooked. The diaphragın is
supported on pivots, and can be turned by means of a lever outside from the
horizontal into an inclined position, so that the meat after having been subjected
to the action of the steam for a certain length of time is caused by the tilting
of the diaphragın to fall into the water of the boiler to complete the cooking
operation.
The apparatus is provided with a detached stand, consisting of a closed metal
receptacle, which can be filled with water heated by the bottom of the fire-box, to
be used for any purpose, the stand being made of such a size that when the
apparatus is not in use it can be placed inside the boiler, so as to economise space.
Where there is a camp fire available the separate heating of the boiler may be dis-
pensed with, the boiler being placed on the camp fire. In this case the space insido
the fuel hopper may be utilized by placing therein a cylindrical vessel in which
coffee, tea, or other drinks may be heated.
Fig. 1 shews a side elevation of a steam cooking apparatus constructed according
to the first above-described arrangement; Fig. 2 shews a vertical section on line
A, B, Fig. 3; Figs. 3 and 4 show respectively sections on lines C, H, and I, K,
Fig. 2.
Within the metal casing a, a, is a tube b, widening out at the lower end, where it
is closed by the perforated plate e, constituting the fire-grate. Within this tube b
is a second tube c of smaller diameter, and arranged eccentrically, so that a space l
exists on one side between the two, which constitutes the flue to the fire-grate,
the fuel being introduced through the tube c, the top of which is kept closed by
alida, while the top of the flue is open. The apparatus here shewn is intended
to burn with charcoal, so that no connection with a chimney is required. The
space a between the casing a and the tube is closed, and filled with water.
Round the lower part of the tube is formed an annular chamber m having an
opening m by which it communicates with the water space a', so that m being
filled with a comparatively small quantity of water in immediate contact with
the fire-box, such water will be in a state of violent ebullition, while that in a¹ will
boil gently. A pipe n leads from the space m to above the water level of a', where
it is formed with a bend by which it can be made to communicate with the
moveable branch p of the pipe o passing down and through the side of the casing a

page_text: where it is temporarily connected to the branch of the vessel A, in which the
meat or other food to be cooked is placed upon tho perforated plate u.
In operating with the apparatus, the fuel being ignited and the cover & removed,
so as to allow the flue to communicate with the atmosphere, the water is brought
to boiling point. The branch p being turned away from the pipe n by means of
the handle 7, steam from the gently boiling water in a will pass down the pipe o
into the vessel A. After the food has been subjected long enough to the action of
this steam the branch p is turned so as to communicate with n, whereupon the
steam from the violently boiling water in m will pass into the vessel A, and com-
plete the cooking operation. A second pipe 7' may be provided closed by a plug or
valve 8, by opening which by means of the chain which is hooked on to a hook at t
steam from a may be conducted to other cooking vessels. When it is desired to
extinguish the fire this is effected by putting on the cover d. Any steam or volatile
constituents that may be evolved from the fuel and accumulate in the top part of
the tube c are by the draught drawn down through the incandescent fuel, and
burnt before escaping through the flue . Beneath the grate e is a shallow ash-pit
formed by the inclined plate f and spaces g, h, to which access is gained by the
door i, and into which the air required for combustion enters through the holes k.
Below the ash-pit is formed an oven B. H is a cock through which hot water may
be drawn off when required.
Figs. 5 to 8 shew the second above-described arrangement of the cooking apparatus ;
Fig. 5 shews a vertical section of the apparatus on line C, D, Fig. 7, when packed
together for transport; Fig. 6 shews a section of the apparatus on line E, F, Fig. 8,
when in uso; Fig. 7 shows a sectional plan on line L, M, Fig. 5; and Fig. 8 shews
a sectional plan on line N, O, Fig. 6.
The receptacle a' is divided by a sloping partition B into an upper compartment
C for containing water, and a lower compartment C for containing fuel, which is
introduced through the tube D, reaching up to above the top of the receptacle a¹;
Saro holes for the admission of air for supporting combustion. Into the open
upper end of a¹ is fitted a moveable extension E in which is a perforated diaphragm
G supported on pivots, and capable of being turned by means of the lever a from
the horizontal into an inclined or vertical position. In the extension E is also
fixed a tube F forming an extension of the tube D, and which is provided with a
removeable cover L, the part E being also closed by a cover J. When not in use
the part E is placed in an inverted position in the casing a³, so as to occupy less
space, as shewn at Fig. 5; K is a closed vessel, which when the apparatus is in use
filled with water, and serves as a stand to the apparatus to protect the ground on
which it stands from the heat. The water in this vessel becoming heated may be
made use of. When the apparatus is not in use the vessel K is packed inside the
water space C, as at Fig. 5. When the apparatus is in use the compartment C is
filled with water, and the fuel in C is ignited, the cover L being removed to pro-
duce the requisite draught up D and F. The meat to be cooked is placed upon the
diaphragm G, where it is subjected for a certain time to the action of the steam
from the boiling water, after which the diaphragm is tilted bymeans of the handle >
so as to cause the meat to fall into the water, and thus complete the operation of
cooking. If desired. a vessel M may be introduced into the tube D for cooking tea
or coffee.
This apparatus is particularly adapted for military purposes as a field cooking
apparatus.
Having thus described the nature of this Invention and in what manner the
same is to be performed, I claim,―
First. The construction of steam cooking apparatus, whereby the meat or other
food to be cooked is first subjected to the action of steam from quietly boiling
water, after which it is subjected to the action of steam from violently boiling water,
or to boiling water itself, substantially as herein described.
Second. The construction of steam cooking apparatus, arranged and operating
as herein described with reference to Figs. 1 to 4 of the Drawings.

page_text: Third. The construction of steam cooking apparatus, arranged and operating as
herein described with reference to Figs. 5 to 8 of the Drawings.
In witness whereof, I, the said Gerard Wenzeslaus von Nawrocki, have here-
unto set my hand and seal, this Thirtieth day of August, in the year of our
Lord One thousand eight hundred and seventy-seven.
GERARD WENZESLAUS v. NAWROCKI. (L.S.)