IMPROVEMENTS IN BAKING OVENS
Year: 1878

page_text: LETTERS PATENT to James Russell Chibnall, of King Street, Hammersmith,
for the Invention of "IMPROVEMENTS IN BAKING OVENS."
Scaled the 9th May 1879, in pursuance of an Order of the Lord Chancellor, and
dated the 23rd October 1878.
PROVISIONAL SPECIFICATION left by the said James Russell Chibuall at
the Office of the Commissioners of Patents on the 23rd October 1878.
JAMES RUSSELL CHIBNALL, of King Street, Hammersmith. "IMPROVEMENTS IN
BAKING OVENS."
This Invention has reference to improvements in the construction of baking
ovens, whereby their action is rendered quicker and more efficacious and
economical.
For this purpose I construct my improved oven with two baking chambers, the
one being directly over the other, access to each being had by separate doors at the
front of the oven. The furnace is built in the front of the oven and on the same
level as the lower baking chamber. The heat from the furnace is made to pass
horizontally, through a flue built along the two sides, back, and part of the front of
the lower chamber, but separated by a partition from the same. Having passed
round to the front of the lower chamber the heat then passes vertically upwards to
the roof of the upper chamber and thence to a flue by which it goes to the
chimney. In order to regulate the heat at different parts of the baking chambers
I provide extra outlets to the chimney, which are fitted with suitable dampers. I
construct the roofs of the baking chambers of plate iron fastened on to reversed T
iron supports. The floors of the baking chambers may be covered with iron or
tiles.

page_text: BAKING OVENS."
This Invention-relates to improvements in bakers' ovens and has for its object
a saving of fuel, labour, and space, greater cleanliness, and a better control over or
_ management of the temperature of the oven as compared with the bakers" ovens
generally employed.
For this purpose I construct my improved oven in the form of a double-oven or
two separate ovens, one above another, which I heat by one and the same fire. I
cause the flame and hot air from the fire to pass through a system of flues, first over
the roof of the bottom oven, whence it passes upward to the roof of the top oven,.
over which it passes and then goes to the chimney. I provide one, two, or more
apertures or passages connecting the flue oven, the bottom oven, with that over the
top oven through which pass the hot air or gases from the fire, thereby heating
both the bottom and the top oven at the same time. To such apertures or passages
I fit dampers, for the purpose of regulating the temperature of the air and gases in
⚫the flues and of guiding such hot air and gases in any required direction according
as they may be more or less opened or closed.
In addition to the method of heating each of the ovens, comprising the double
oven from their respective roofs, I also communicate heat to the bottom oven from
the fire through the wall or partition separating the same from the bottom oven,
which wall may be made of any thickness suitable for the purpose, and to the top
oven through the floor of the same from the flue or hot air chamber immediately
underneath.
In order that my Invention may be clearly understood I have annexed hereto a
Sheet of Drawings, in which,--
Figure 1 is a front elevation of my improved oven; Figure 2 is a section of
Figure 1 through the line A, B; Figure 3 is a vertical cross section of the same
through line C, D; Figure 4 is a horizontal section through line E, F; Figure 5 is
a horizontal section through line G, H; Figure 6 is a horizontal section through
line 1, K; Figure 7 is a horizontal section through L, M. 1 is the bottom
oven; 1a, door of same; 2 is the top oven; 2ª, door of same; 3 is the fire door;
4, the fire grate; 5 is the passage along which travels the hot air and frame from
the fire, the direction being shewn by arrows; 6 is the flue or hot air chamber over,
the bottom oven, of which part of the heat contained therein may be caused to pass
through the floor of the top oven, such floor being made of suitable thickness and
material. The Drawing represents an oven in which the heat is not required to
permeate upwards through the floor of the top oven. 7 is the flue or hot air
chamber over the top oven; 8 are the apertures or passages connecting the flues
or hot air chambers over the ovens; 9 is the position the aperture to the chimney.
would occupy if the top of the oven were shewn; 10 is the chimney through which
the hot air and smoke passes from the flue or hot air chamber over the top oven;
11 is the tiled floor of the bottom oven; 13, concrete underneath the same; 14 is
the tiled roof of the bottom oven supported on tee irons 15; 16 is the tiled roof of
the hot air chamber C, supported on channel irons 17; 18 is the tiled floor of the
top oven, between which and the roof of the hot air chamber 16 is a layer of sand;
19 is the tiled roof of the hot air chamber 7; 20 are the baffle or guide walls which
guide the hot air over area of the roof of the top oven. The dotted lines x
(Figure 2) indicate direction of furnace flue.
Therefore when the double oven is in operation the flame and hot air pass from
the fire grate 4 along the passage 5 gradually upward until it reaches the level of
the flue or hot air chamber 6, through which it passes through one or more

page_text: passages 8 (regulated by dampers) upward to the flue or hot air chamber 7, and
thence through the chimney 10 to the atmosphere. In this manner the two ovens
may be maintained at any desired heat by one fire.
Having now described my Invention, and the means of carrying the saine into
practical 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 according to the special construction
of "baking ovens," substantially as described and represented in the different
Figures of the accompanying Drawings.
In witness whereof, I, the said James Russell Chibnall, have hereunto set
my hand and seal, this 5th day of May, in the year of our Lord One
thousand eight hundred and seventy-nine.
JA8. RUSSELL CHIBNALL. (L.S.)