A NEW AND IMPROVED OVEN FOR BAKING BREAD, MEAT, AND OTHER FOOD, APPLICABLE FOR OTHER PURPOSES REQUIRING FIRE OR HEAT
Year: 1879

page_text: LETTERS PATENT to Henri Adrien Bonneville, of the British and Foreign
Patent Offices, 18, Rue de la Chaussée d'Autin, Paris, France, and 5, Piccadilly,
in the County of Middlesex, Patent Agent, for the Invention of "A NEW AND
IMPROVED OVEN FOR BAKING BREAD, MEAT, AND OTHER FOOD, APPLICABLE
FOR OTHER PURPOSES REQUIRING FIRE OR HEAT." A communication from
Charles, Lesobre, of Rue de Vieille, Estrapade, Paris, France.
led the 2nd March 1880, and dated the 6th September 1879.
COMPLETE SPECIFICATION filed by the said Henri Adrien Bonneville at the
Office of the Commissioners of Patents on the 6th September 1879.
HENRI ADRIEN BONNEVILLE, of the British and Foreign Patent Offices, 18, Rue
de la Chaussée d'Antin, Paris, France, and 5, Piccadilly, in the County of
Middlesex, Patent Agent. "A NEW AND IMPROVED OVEN FOR BAKING BREAD,
MEAT, AND OTHER FOOD, APPLICABLE FOR OTHER PURPOSES REQUIRING 'FIRE OR
HEAT." A communication from Charles Lesobre, of Rue de la Vieille, Estrapade,
Paris, France.
The Invention relates to a new or improved permanent or portable oven with
a turning or a stationary sole, heated from within or without at will, and designed
for the continuous baking of bread, sea-biscuit, pastry, and any other alimentary
substances, as well as the drying of all matters that admit thereof.
The Invention is illustrated in the accompanying Drawings, in which Fig. 1
represents the oven with a turning sole and self-acting cleaner, and heated from
inside; Fig. 2 represents the oven with a turning sole and vault made of fire-proof.
materials, and outer fire-box; Fig. 3 represents the mechanism of the oven with
a turning sole; Fig. 4 is a sectional view of the oven with a turning or stationary
sole through the centre of the fire-box; Fig. 5 is a front view of the portable
oven; Fig. 6 is a sectional vertical view of the portable oven through the centre
of the fire-box; Fig. 7 is a perspective view of a square portable oven; Fig. 8, a
sectional vertical view of the same; and Fig. 9, a sectional vertical view of a
portable oven with a turning sole provided with rollers...
'
In order to bake bread and other articles of food well there are several indis-
pensable requirements which have been proved by long experience.
The ordinary oven consists of a simple space or compartment of elongated form
with an elliptic vault or crown. The hearth or sole is the horizontal surface of the
oven on which the wood burns for heating purposes.

page_text: It is constructed of bricks, or stones in the place of bricks in countries where it
is impossible to procure any.
During the heating process the caloric is stored little by little in the mass of the
construction, and especially in the vault or crown which is exposed to the direct
action of the flames.
In order to endeavour to regulate the heat as much as possible the oven-keeper
moves the fuel successively towards the different points of the sole and the vault,
but he can only succeed approximately, as he has and can have no other guide but
routine for the heating operation.
As soon as the oven is supposed to have reached the desired temperature it is
cleaned and the bread put in. The dough is immediately caught by a maximum
temperature, which causes it to puff up rapidly and forms the crust. The baking is
afterwards effected by the gradual absorption of the heat which is disengaged and
radiates on all sides, but decreasing little by little. in intensity.
The conditions of good baking are generally found in this series of phenomena
relative to the different states of the heat, which radiates at first with great force
and afterwards gradually diminishes in intensity as required. But the said ordinary
oven has many disadvantages.
First, it can only be heated with wood, which is expensive, and takes up very
much room for storage which is often a cause of fire; wood has besides been long
replaced by coal in all other trades.
Next, the heating is effected inside the oven in an unequal and irregular way;
there is nothing to show that the required temperature is attained, and besides
the fuel leaves on the sole remains of cinders and ashes, which cause much dirt and
necessitate very laborious cleaning.
Moreover, the said inside heating renders the baking operations unavoidably
alternative, which gives rise to great loss of time and manual labour.
Lastly, as the further end of the oven is filled first when the objects are put in
it follows that the loaves or other articles that are put into the oven first are taken
out last, as those near the mouth of the oven which were put in last must be taken
out first.
The problem to be solved is then as follows:-
The conditions of heating, storing, and gradual radiation of the caloric, as above
described, being given to observe the said conditions whilst offering.
To those who will not give up the inside heating all the advantages arising from
the mobility of the sole, which allows of regulating the baking, of filling and
emptying the oven more rapidly by means of instruments shorter and easier to
handle, and lastly, of collecting the wood-ashes and thoroughly cleaning the sole
of the oven at a single operation.
To others all the combined advantages of an independent or separate fire-box
which does away with the laborious task of heating by wood and cleaning the
sole, as well as the other advantages just mentioned, arising from the mobility of
the sole. The said separate fire-box allows of heating very forcibly with coal,
coke, or any other fuel, of always ascertaining exactly the temperature of the oven by
. means of a thermometer, and of baking continuously with the greatest ease and
cleanliness.
The said sole consists of an upright arbor or spindle turning in a tempered
socket firmly secured in a foundation-bed. The frame is formed of radii supported
by buttresses, the former fixed to the upper hub in mortises and the latter by bolts
on to the lower one. An iron ring fitted to the end of the radii, and rising up
about 2 or 3 inches above the level of the radii, surrounds the sole. On the radi
is a sheet-iron plate, on which fire-tiles are laid on clay mortar and flush with the
top of the ring.
The sole is balanced by two cramped cast-iron collars, one below the second hub
and the other at the lower part of the arbor. The said collars may be made of two
parts, connected by bolts in order to allow of always giving the necessary play
round the arbor.

page_text: A bevil-wheel mounted above the second collar is set in motion by a horizontal
shaft resting on two bearings, and provided at one end with a pinion and at the
other with an endless-chain wheel. The said endless chain is connected with the
pinion of a crank by which the motion is imparted. The different parts by which
the motion is transmitted are outside the oven, and therefore easy of access and
protected from the action of the heat.
Again, the sole may be rotated either on rollers or by levers, or by causing the
arbor to pass through the oven and placing the gearing above, or by any other
mechanical contrivance.
In order to protect the endless chain and its gearings from all dirt they arc
covered by means of a sheet-iron plate, which can be taken off and put on.again
when desired by means of finger-screws.
When the oven is heated inside, a brush-roller is placed on one side of the oven
reaching as far as the centre thereof, and provided with little steel blades for
collecting the wood-ashes and cleaning the sole at the same time, the said brush-
roller being set in motion either by the rotation of the sole or by a small outside
mechanism.
An extinguisher placed in a niche below the brush-roller collects the remains of
the combustion.
Any ordinary oven may be transformed at little cost into an oven with a turning
sole heated inside.
If it is desired to make the same oven, heated from inside, also capable of being
heated from outside by a separate fire-box, in which any fuel, wood, coal, coke, or
peat can be burnt, the said fire-box, which may be moveable on rollers, is placed
either below the sole or on one side of the oven level with the sole, and a series of
cast-iron or fire-proof flues for the circulation of the smoke is contrived under the
sole in the walls and brick crown. In this case a thermometer, with quicksilver,
in the shape of a square, or any other instrument may be used to measure the exact
temperature.
If it is only desired to heat the oven outside, the fire-box is placed below the
turning sole, the flucs are made in the thickness of the masonry, and the heat
circulates above the vault of the oven, which is made of bricks, tiles, or fire-proof
materials riding on T-irons. If it is desired that the said T-irons should not be
seen inside the oven grooved bricks or fire-proof materials are used, in which the
flanges of the T-irou are buried. The vault or crown may also be made of sheet-
iron, in which case it is supported by iron-hooks hanging on T-irons which form the
top of the oven crown. The smoke afterwards escapes up a chimney, the draught
of which is regulated by means of a damper which allows of increasing or decreasing
the same, and consequently of graduating, the temperature of the oven according to
the requirements of good baking.
The door of the fire-box is provided with clamps for receiving a counter-door
with books, which serves as a screen and wards off the greatest heat of the fire, and
can thus be easily changed when it is no longer fit for use.
The lighting of the oven, and particularly that part of the sole brought in front,
is facilitated by a lamp or jointed gas-burner by the side of the mouth of the oven
inside or outside, thereby allowing of looking over all the objects in the oven in an
instant.
In order to utilize the heat still further, a second and even several other ovens,
with moveable or stationary soles, may be placed above the first. In this case
the heat passing above the vault or crown heats the under side of the second oven
and then circulates above the crown of the same, and so on for the other ovens
placed above, and the smoke escapes at last by the chimney, as has just been
stated.
Instead of making the casing of the oven of masonry it may be made by means
of pannels, in which tiles or bricks are set, or by means of sheet or cast-iron plates
fitted and connected together, or else by means of concentric cylinders. Between
these plates or cylinders are placed ashes, glass slags, sand, or any other suitable

page_text: material in order to preserve the heat, or passages are even left for the air to avoid
overheating at certain points.
Instead of several mouths there may be only one, and then moveable grates are
substituted for the compartments, of any desired number, fixed on brackets or rods,
so as to be able to lower or raise them at pleasure.
By means of special features in the manufacture the different parts of the said
apparatus can be adjusted and fitted or even clamped or booked in each other,
which makes them as easy to be conveyed, set up, or removed as a piece of
furniture.
The said oven may also be mounted on wheels so as to form a campaign oven.
It is set up on spring sockets in order to avoid the disadvantages of the jolting and
roughnesses of the roads. If it is desired to bake the bread on tiles the said tiles
are set in frames, where they are fixed by means of lugs, grooves, or in any other
way so as not to be damaged on the route; or, again, the bread may be baked on
sheet-iron plates isolated from the sole of the oven by means of little projections
underneath, very short in height, in order to isolate the plate from the sole of the
oven, and to allow the heat to surround the object to be baked on every side. The
said plates will serve at the same time for raising the dough.
The sole may be made of cast-iron,. sheet-iron, wrought iron, grating or
otherwise.
A mouth is placed at each end of the oven in order to make the filling and
emptying of the oven easier, so as to hasten the service and be able easily to
take out first the loaves which were put first into the oven. This apparatus may
be provided with the same accessories, above described, such as boiler, furnace, and
others.
When the campaign is once over the oven may be put in a coach-house by
leaving it on its wheels; or it may be laid on trestles and used as an ordinary oven
in any laboratory, or on board ship, or elsewhere.
The vehicle may be arranged so as to receive at the same time a mechanical
kneading-trough for the use of the oven.
Above the fire-box a steam generator may be set up of the required shape, and
a motive power thus obtained which is utilized for moving mechanical kneading-
troughs, or for any other purpose.
One or more gas retorts even may also be placed above the fire-box for
obtaining the gas required for the lighting of the works or of private houses.
Any metal vessel may again be placed on one point of the oven, on which water
is let fall drop by drop by means of a tube and a cock placed outside. This water
thus brought into contact with a metallic surface at a temperature of 300 to
400 degrees evaporates instantaneously, and produces the additional steam which
may be required for certain loaves or other objects.
In the mass forming the casing or the filling of the oven, or on any other point
on the line of smoke and hot gases, a boiler may also be placed, which is caused to
dip and sink on all sides into the smoke and hot gases in order to heat the water
required for the laboratory, private baths, or any other purpose. The said boiler
is provided with a float which regulates the inlet cock.
In one side of the oven an iron cupboard or drying-stove may be arranged, pro-
vided with ledges or shelves, the distance between which may be widened at will
for keeping the objects hot after they are baked.
A drying stove of any desired dimension may also be put above or next to the
oven for the sweating or drying of any objects whatever, such as sea-biscuits,
Rheims' biscuits, ginger-bread, or other similar objects.
One or more heat-mouths may be contrived in the oven, and communicate
with the drying-stove in order to raise the temperature of the said drying-stove
'to the degree desired. The said temperature. is regulated by valves, opening or
closing at will.
Similar heat mouths may be applied to the heating of shops, warehouses, offices,
or even rooms on the same floor or on higher floors.

page_text: In trades where kitchen stoves are used, a stove may be set up in the thickness
of the masonry, so that the said stove may be heated by the fire-box of the oven
without any outlay of fuel, or else again the said stove may be made by the side
of the oven and the hot gases caused to pass from the fire-box of the stove into
the inside of the oven so as to heat the latter, or at least to economise the fuel
considerably.
Lastly, above the floor of the oven and in the thickness of the side thereof, in
order to concentrate the heat, an ordinary oven may be set up, heated inside with
wood, to take the place of the other one in case of insufficiency or repairs.
Having thus fully described the said Invention, and the manner of carrying the
same into effect, I would have it understood that I do not confine myself to the
precise details above enumerated, as these may obviously be modified without
departing from the principle of the Invention; but what I claim is a new or
improved permanent or portable oven, with a turning or a stationary sole heated
from within or without at will, and designed for the continuous baking of bread,
meat, sea-biscuit, and any other alimentary substances, the said oven being also
applicable for other purposes requiring fire or heat, substantially as above described
and represented in the accompanying Drawings.
In witness whereof, I, the said Henri Adrien Bonneville, have hereunto set my
band and seal, this First day of September, in the year of our Lord One
thousand eight hundred and seventy-nine.
H. BONNEVILLE.
(L.S.)