Improvements in the Construction of Portable Ovens for Military and other Uses.
Year: 1892

page_text: Date of Application, 22nd Dec., 1892-Accepted, 28th Jan., 1893
COMPLETE SPECIFICATION.
Improvements in the Construction of Portable Ovens for Military
and other Uses.
A communication by ADOLPHE GODELLE, of Marseilles, in the Republic of
France, Officer of the Administration.
I, WILLIAM PHILLIPS THOMPSON F.C.S. M.I.M.E. of the Agency for
Foreign Patent Solicitors 6, Lord Street, Liverpool and 6, Bank Street, Man-
chester, both in the County of Lancaster & 323 High Holborn in the County
of Middlesex Civil Engineer 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 for its object a metallic octagonal oven, intended for making
bread for troops during manoeuvres or when on a campaign.
This improved oven is entirely constructed of metal (sheet and cast iron); its
peculiar form, which is quite novel, in no wise hinders the work of inserting and
withdrawing the bread; the principle of its construction is applicable to any sized
oven, so that its capacity is unlimited; its weight is proportionate to its capacity.
Nevertheless, in order to give an idea of its lightness, it may be stated that a
pattern of oven for baking 200 rations producing 150 kilogrammes of bread per
baking only weighs 470 kilogrammes, without packing, and does not cost more
than 200 francs, which is insignificant when compared with the cost of similar
apparatus. To sum up these properties, it will be sufficient to state that the
endeavour has been, and such endeavour has been successful, to produce a very
light and very cheap oven and one which is very easy to construct, to fit up and
to take to pieces, and also to transport.
On the accompanying drawings
:-
Figure 1 is an elevation of the oven all fitted up.
Figure 2 is a plan view.
Figure 3 is a section on the line 1-2 of Figure 2.
Figure 4 is an elevation of the rivetted plate forming the door framework.
Figure 5 is a side view of the same.
Figure 6 is an elevation of the door itself.
Figure 7 is a side view of the door.
Figure 8 is a view of a simple rivetted plate.
Figure 9 is a pin or bolt hereinafter referred to.
Figure 10 is a headed bolt for holding the truss-work.
Figures 11-12 are an elevation of the right and left wing pieces.
Figure 13 is a plan of the earth shield.
Whatever may be the type adopted, this oven is invariably composed of forty-
three picces, of which the following are the details:
One key or centre piece A of the dome, of cast metal into which the trusses B B
converge. This key is octagonal in form, it is hollow and is provided with a
vertical opening a on each face, a projection 6 on each angle, and an iron handle c
screwed into its upper part (Figures 1, 2, 3 of the accompanying drawings):
Eight trusses B B or rafters of T iron, all similar and interchangeable
:
(Figures 1, 2 and C of bar iron, one of which, C¹, is curved round at each
Eight tie bars
extremity on the door side (Figure 2):
Eight sheet metallic roof plates D D, two of which, D¹ D', bear the supports of
the chimneys hover the oven. Each of these sheets of metal is provided with
two rivetted angle irons d d for strengthening the roof of the oven (in larger ovens

page_text: than those for 200 rations, these sheets of metal may be made in two parts, in order
to facilitate their packing):
Eight rivetted sheets of metal E E, Figures 1 and 8, one of which, E', (Figures 4
and 5) is cut out for the oven door framework. This latter is provided with two
angle irons e e rivetted vertically on its external face, and which serve as supports
for the winged pieces J J; a frame f, Figure 5, of flat iron, is fixed on the internal
face of this plate and round the doorway in order to protect the sheet of metal
against the blows of a poker. These eight sheets of metal have each a longitudinal
angle iron g g in order to support the pressure of the earth as hereinafter:
Two pipes F F with dampers h h, having at their upper end a circle ii of narrow
square iron, rivetted, and which sustains the chimneys:
Two chimneys G G intended to increase the draught (Figure 3):
Two damper rods H H, each in two parts so as to facilitate their packing, and
connected by means of chain pins jį (Figures 2 and 3):
One earth shield I, provided with an angle iron k for keeping off the earth
which is on top of the furnace (Figures 1, 2 and 13):
Two wing pieces J J, each provided with a pin and a hook ทน which are
inserted in a hole made for this purpose in each of the trusses (Figures 1, 11
and 12):
One door plate K of sheet metal of five or six millimetres in thickness, provided
with a handlen (Figures 6 and 7).
To these pieces it is preferable to add :-
Eight similar bolts oo having countersunk heads and projections of about
020 diameter (Figures 1, 2, 3 and 10):
Thirty-two similar pins p p of 016 in diameter, necessary for fitting it up,
(Figures 1, 2, 3 and 9).
The metallic octagonal oven may be fitted up with exceptional facility and rapidity,
it does not require any preliminary planning out, and the ground need not be
specially chosen.
The oven may be erected equally well upon sand, earth or rock, seeing that no
part of it is inserted in the soil. This important result has been attained by doing
away with supports, spits and attachments which, at present, are employed in other
portable sheet metal ovens.
The setting up, which may be performed by two workmen of any sort, is done
in fifteen minutes in the following manner :-
First of all the key of the dome A is placed at about 50 centimetres above the
soil by means of some suitable support in the centre of the place chosen for the
erection of the oven.
The eight top points of the joists B B are then inserted indiscriminately into
the eight vertical openings a a of the key of the dome.
Eight bolts oo are then fixed with their heads downwards (after their nuts
have been removed) in the holes of the feet of the trusses; each nut to be placed
beside its bolt. .
The eight feet of the trusses are then connected by means of the eight tic
bars C C, two tie bar ends being on each of the bolts; the tie bar C³, curved at
its extremity, must be placed first on the same side as the door.
The nuts must be then screwed on their respective bolts and tightened up by
means of a key, then the support of the key of the dome may be taken away.
Then the under part of the furnace may be put up, if that has not already been
done, by arranging it at a suitable inclination, about 13 m. from the back to the
front, but it is preferable to form the floor before fitting up the oven.
The eight rivetted metallic plates E E must be then placed in position, taking
care to place the one E', which is cut out, at the side where the elbowed tie bar C¹
is placed, the angle irons e e and y g with which they are provided must be outside
and above.
These plates are then fixed two by two with sixteen bolts p p inserted in holes
arranged in the lower part of the trusses forming the jambs.

page_text: The eight metallic plates D D, forming the roof, are then placed in position;
the two plates D' D', which are to receive the dampers hh, must be arranged,
the one on the left and the other on the right of the plate on the side diametri-
cally opposite to the door; these two plates D'D' are therefore separated by a
third one.
These metallic plates must then be fixed with sixteen bolts p p, proceeding in the
same manner as has been described for the side plates.
The wing pieces J J must then be placed on the left and right of the oven door,
where they are held by the angle of each vertical angle bar ee of the door of the
oven and by a hook m, with which each of them is provided; this hook being
inserted in a hole in the truss.
The earth shield I is then attached to the angle iron k and drawn forwards
in order to fix the two external pins of the wings in the holes prepared
for them.
In order to facilitate this work, it is preferable to draw out the two pins which
retain the dome plate, if they have been already placed, then to attach the earth
shield and then to replace the two pins.
The pipes F F, carrying the dampers hh, must then be placed in position, care
being taken to distinguish that of the left and that of the right by the slope on their
lower extremity and the position of the pins of the damper, and then the chimneys G G
must be fitted in them.
A hole must then be dug for the workman, and the material removed must be
This
employed for covering the oven entirely to a thickness of 25 m. or 30 m.
thickness may be increased if it be thought desirable for keeping in the heat without
fear of the oven giving way.
The rods H H of the dampers hh must then be attached by means of chain
pins with which they are provided, and they may be allowed to lie on the earth
which forms the covering of the furnace.
.The. taking down of the oven is performed in the reverse order to the fitting up
in ten minutes by two workmen.
When such has to be done, it must not be forgotten to support the key of the
dome before unscrewing the nuts of the bolts.
No particular floor plate has been adopted for this octagonal metal oven, the
various floor plates employed hitherto for field ovens may be used for this one.
This floor may be of bricks or tiles or may be made simply of clay beaten hard
and rammed down.
The various operations relating to cooking, packing, heating, and re-heating
and filling and emptying are carried out in the case of this oven under the same
conditions as has been usual in other portable metal ovens, and therefore it is not
necessary to describe them. The same applies to the packing which is rendered as
easy as can be by the division and the light weight of the parts.
The octagonal metallic oven hereinbefore described presents substantial advantages
over the other field ovens hitherto employed, in fact the construction of this oven
may be undertaken by any military artificers, provided they have a forge, a vice,
tools of the proper sort and a locksmith or mechanician.
Its construction does not necessitate much forge work and does not require a very
great deal of skill on the part of the workman.
Repairs, so to speak, are nil, seeing that, as the furnace is erected and pulled down
again without it being necessary to hammer it, there is no fracture of the parts such
as usually arises from misdirected blows.
The metal plates do not need to be straightened each time that they are used,
for the angle irons with which they are provided hold them sufficiently straight,
resting on the T irons of the trusses, these angle irons support all the weight of the
earth forming the covering of the furnace and their adherence to the metal plates
by means of rivets prevents these latter from buckling.
The moderate cost of this furnace, its light weight, the rapidity and simplicity of

page_text: the operations for erecting and pulling it down complete, in the most perfect manner,
the advantages herein before enumerated.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is :-
1. In ovens of the hereinbefore described kind, providing eight similar
trusses B, B, of T iron, which are interchangeable and will all converge at their
upper part to an octagonal key A of the dome, and are to be held at their lower
ends by eight tie bars C C of flat iron, one of which, C¹, is elbowed at each end to
form the side for the door; trusses and draw bars being connected by eight bolts oo,
substantially as herein before described.
2. In ovens of the hereinbefore described kind, providing eight sheets of
metal D D forming the cover, two of which, D' D¹, carry the sockets of the
dampers, and also eight rivetted metallic plates E E, one of which, E', is cut
out for the doorway of the oven, resting on the above named trusses, with which
they are connected by means of thirty-two pins p p, substantially as hereinbefore
described.
3. In ovens of the hereinbefore described kind, providing a door plate cut out
of a rivetted sheet of metal protected on the right and the left by winged pieces J J
and at its upper edge by a plate I for shielding off the earth, substantially as
herein before described.
4. In ovens of the hereinbefore described kind, providing two pipes F F with
dampers, arranged to receive the two chimneys G G for the purpose of accelerating
the draught, which is regulated by means of the draw rods HH, substantially as
hereinbefore described.
5. The general arrangement and combination of the various parts mentioned in
the foregoing claims and forming a very light and a very cheap oven, which is
extremely easy to construct, to fit up and to pull down and to transport, sub-
stantially as has been herein before described in a detailed manner.
Dated this 21st of December 1892.
WM. P. THOMPSON & Co.,
Agents for the Applicant.