Year: 1892

page_text: Date of Application, 27th July, 1892-Accepted, 1st Oct., 1892
According to my invention the baking trough or hearth is preferably carried
by rails h of section provided with angle irons h' and fixed to appropriately
formed brackets * securely bolted or otherwise attached to the inner wall a' of the
baking oven.
The heating device is composed of a closed smooth or corrugated tubular body,
the rear end of which is connected by a knee piece or its equivalent to the
chimney o, the lower part of which is preferably surrounded by a box-like casing p,
whereas the forward end of the heating device is closed by means of an appropriate
furnace door or doors.
According to this construction of baking oven, the air heated by coming in
contact with the heating device ascends into the baking compartment under the
baking trough or hearth g through the lateral spaces left between the angular or
other brackets ³ and ascends above the baking trough or hearth in order to give
the requisite upper heat. As soon as the air has given off a part of its warmth,
the same will descend and be replaced by the following air which has become
heated by contact with the heating device, and in this manner a continuous
circulation of the same quantity of air will be produced and maintained, thus
enabling me to effect a very uniform and rapid baking.
When the baking oven is employed for portable purposes, for instance field
bakery, and is arranged on the frame work of a carriage, I prefer to protect the
concentrical tubular body a a' forming the mantle of the baking oven against
radiation so as to prevent loss of heat, and to enable me to carry on and maintain
a continuous and economical process.
In order to reduce the weight of the baking oven as far as possible and at the
same time produce an effective insulation not liable to be in any way damaged by
the frequent and rapid movement of the baking oven, I prefer to employ asbestos
board m and hose like fabric n filled with fossil meal or other appropriate refractory
material.
The layers of asbestos board m are so separated from each other by a space
formed by inserting hose-like fabric n filled with fossil meal or the like at
appropriate distances apart, that a layer of air will remain between the two layers
of asbestos board, and thus produce an effective insulation.
The baking trough or hearth can if desired be provided with rollers or wheels,
so that the same can be readily inserted in or withdrawn from the baking oven.
As aforementioned my improved baking oven can be used not only as portable
but as stationary baking oven, and contains the essential feature according to
which the furnace is arranged in a closed heating device by means of which the

page_text: air radiating from the said heating device will ascend and give off a large portion
of its heat to the baking compartment, re-descend to the heating device to be
again heated, and recontinue its circulation in the manner aforedescribed, thus
enabling me to carry on the heating during the removal of the old and insertion of
the fresh batch without loss of heat to any extent, and without being compelled to
extinguish the fire and reheat for each batch.
I wish it to be expressly understood that I do not confine myself in any way to
the special form or dimensions of the baking oven, as these can be varied according
to requirements; and it will also be evident that the method of insulation can be
varied according to the circumstances of the case.
Having now particularly described the nature of this invention and the manner
in which the same is to be performed, I declare that what I claim is :-
1) A baking oven which can be used as a stationary or portable oven consisting
substantially of the heating device d, composed of a closed body communicating
with the chimney o, and capable of being continuously kept in operation, and of a
baking trough or troughs or hearth g which is or are carried by appropriate
brackets fixed to the walls a a' of the baking oven between which the hot air can
ascend, which after giving off its warmth circulates back to the heating device to
be reheated, substantially as described and shown in the drawings.
2) In a baking oven of the kind mentioned in the foregoing claim the insulation
between the mantles a a' for preventing radiation of heat, composed of alternate
layers of asbestos board m and hose-like fabric n filled with fossil meal so that a
layer of air is left between the layers of asbestos board, substantially as described
and shown in the drawings.
3) My improved baking oven substantially as and for the purposes described in
the foregoing Specification and shown in the accompanying drawings.
Dated 27th July 1892.
GEO.
DOWNING,
8, Quality Court, London, W.C., Agent.