O
Year: 1887

page_text: Date of Application, 15th Feb., 1887
Complete Left, 15th Nov., 1887
Complete Accepted, 16th Dec., 1887
I, DAVID MCARTHY of 23 East Maitland Street, Edinburgh, in the County of
Midlothian, North Britain, Architect, do hereby declare the nature of this invention
to be as follows:-
This Invention which relates to improvements in Bakers Ovens, has for its object
to produce an equable heat throughout the saine, so as to allow of the baking being
carried on continuously and without interruption.
This continuous uniform heat is obtained by sets of double pipes partly filled with
liquid, the said liquid being raised to a considerable temperature by a furnace or
heating chamber.
A gauge indicates the pressure on the beforementioned pipos,
while the temperature in the oven is registered by a mechanical arrangement
regulating the supply of air to the furnace, or, the draught in the flues.
The furnace may be placed in any convenient position at front, back, or either side
of the oven as required. From the furnace several sets of two pipes each, containing
half or other proportion of their volume of water or other liquid are led under an iron
tile, or other sole of the oven, then rising at the back, end, or side of the oven, as the
case may be, are carried along the roof of the same, and back again into the furnace,
thereby completing the circuit. Any number of sets may be used according to size
of oven, each set being distinctly separate, endless, and having a cross connection
formed with a nipple, cone, or other branch for the purpose of maintaining a constant
circulation. By this means a uniform temperature is obtained in all parts of the
oven and as the pipes, according to this Invention, do not require to be inclined,
the heated pipes are kept throughout at an equal distance from the goods being
baked.
The regulator which governs the draught in the flues, or the supply of air to the
furnace is worked by the expansion through heat of a copper rod, or by the
equivalent thereof, acting upon a lever, and double set of pinion wheels or their
equivalent, which move an index pointer over a suitably engraved plate thereby
indicating the temperature within the oven. Attached to the spindle, carrying the
pointer before referred to is a toothed wheel which gears with a toothed rack
operating upon a door or its equivalent to check the supply of air to the furnace when
the temperature becomes too intense within the same or lower the damper in the fluo
thereby reducing the draught in the chimney.

page_text: The waste heat from the furnace can be utilized for the heating of water to be used
in the bakehouse or other parts of the premises by inserting a coil of pipes in the flue
and connecting the same to adjoining tanks. Hot plates, Prooving presses and
such like may all be heated from the same fire by means of reduplicated circulating
pipes.
The interior of the oven is illuminated by means of a gas jet placed in chamber
provided for that purpose, and steam is stored in a suitable tank for use in the oven-
such as in baking Vienna bread-obtained by means of a coil of pipes within the
furnace connected with above tank.
It is to be understood that this Invention applies to all kinds of ovens such as fixed,
portable, and ships ovens.
D. DRYSDALE AUSTIN,
101, St. Vincent Street, Glasgow,
Petitioner's Agent.
I, DAVID MARTHY of 23 East Maitland Street, Edinburgh, in the County of
Midlothian, North Britain, Architect, 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 :-
My Invention which relates to improvements in Bakers ovens, has for its object to
produce an equable heat throughout the same, so as to allow of the baking being
carried on continuously and without interruption.
This continuous uniform heat is obtained by sets of double pipes partly filled with
liquid, the said liquid being raised to a considerable temperature by a furnace or
heated chamber. A gauge indicates the pressure on the beforementioned pipes while
the temperature in the oven is registered by a mechanical arrangement regulating the
supply of air to the furnace, or the draught in the flues.
The furnace may be placed in any convenient position at front, back, or either side
of the oven as required. From the furnace several sets of two pipes each, containing
half or other proportion of their volume of water or other liquid, are led under an
iron, tile or other sole of the oven, then rising at the back, end or side of the oven,
as the case may be, are carried along the roof of the same, and back again into the
furnace, thereby completing the circuit. Any number of sets may be used according
to size of oven, each set being distinctly seperate, endless, and having a cross
connection formed with a nipple, hollow cone, or other branch for the
of
purpose
maintaining a constant circulation. By this means a uniform temperature is obtained

page_text: in all parts of the oven, and as the pipes, according to this Invention, do not require
to be inclined, the heated pipes are kept throughout at an equal distance from the
goods being baked. The temperature of the oven is reduced as desired by means of
throttle valves, worked by lever handles.
The regulator which governs the draft in the flues, or the supply of air to the
furnace is worked by the expansion through heat of a copper rod or coil enclosed in
a cast iron box, with suitable grooves secured to the inside of front wall of oven, or
by the equivalent thereof, connected to spindle passing through wall, inside of a
hollow tube, where it may indicate by a pointer upon an ordinary dial, the tem-
perature within the oven. To the end of this spindle would be fixed a toothed wheel
working on a toothed rack, attached to a lever, fixed to the valve in the air flues, to
check the supply of air to the furnace, when the temperature becomes too intense
within the same, by shutting the valve in the flue.
The waste heat from the furnace can be utilized for the heating of water and
generating steam, to be used in the bakehouse or other parts of the premises by
inserting a coil of pipes or their equivalent in the flue or furnace and connecting the
same by means of flow and return pipes in the usual way to adjoining steam cylinder,
partly filled with water, supplied by an injector or its equivalent, and having glass
water gauge, pressure gauge, safety valve and other necessary fittings. From this
cylinder steam can be taken for all necessary purposes-by means of pipes governed
by valves Hot plates, Proving presses,, and such like may all be heated from the
same fire by means of reduplicated circulating pipes.
The interior of the oven is illuminated by means of a gas jet, placed in chamber
provided for that purpose.
It is to be understood that this Invention applies to all kinds of ovens, such as
fixed, portable and ships ovens, of one, two or three decks.
In order that my said Invention may be properly understood and readily carried
into effect, I will now proceed to describe the drawings hereunto annexed.
Figure 1, is a front elevation of a bakers oven, constructed according to my present
Invention.
Figure 2 is a horizontal section of the same, taken on the line A B Figure 4.
Figure, is a horizontal section taken on the line C, D, Figure 4.
Figure 4, is a longitudinal section, taken on the line E F Figure 1.
Figure is a transverse section taken on the line 6. H. Figure 4.
In fitting up an oven in accordance with my present Invention, and as represented
upon the annexed drawings, I place the furnace "a" which is built in the ordinary
way with fire clay bricks in front of, and under the oven, but it is to be understood
that it may be arranged in any other convenient position. Rising from the furnace " a,"
and in contact with the fire, several seperate, endless, doubled pipes b, containing
half or other proportion of their volume of water or other liquid are led under an
iron, tile, or other sole c, of the oven, up at the back and along the roof of the same,
then doubling, return along the roof down at the back of the oven and under the
sole c, into the furnace a, thereby completing the circuit. Any number of endless,
doubled pipes b, may be used according to size of oven (17 are shewn on the annexed
drawings for the purpose of illustrating the arrangement of the pipes). Each pipe b,
has a cross connection d, Figure 2, formed with a nipple hollow cone or other branch,
for the purpose of maintaining a constant circulation. Instead of a portion of the
pipe b, dipping down into the furnace a, as hereinbefore described and as represented
at Figures 4 and 5 of the annexed drawings, that portion may be kept level and
arranged equally over the fire, forming flues of themselves, and thus obtaining more
heat if necessary.
The temperature of the oven is reduced as desired by means of throttle valves
e, in
the flue f, the said throttle valves being operated by hand, by means of shafts g,
on the front ends of which shafts the hand levers h, are secured.
The regulator which governs the supply of air to the furnace a, is worked by the
expansion through heat of a copper rod or coil enclosed in a cast iron box with
suitable grooves, the said box being secured to the inside of front wall of oven.
The

page_text: beforementioned copper rod or coil is connected to a spindle which, within a hollow
tube passes through the wall and operates upon the pointer of an ordinary dial
gauge thus indicating the temperature within the oven. To the outer end of this
spindle is fixed the toothed wheel i, gearing with the toothed rack j, which is formed
upon the upper end of the crank k, as represented at Figure 1. This crank is secured
to the outside end of shaft i, Figure 3, by means of which it actuates the valve or
damper m, within the air flue n, so that when the temperature in the furnace a,
becomes too intense, the supply of air thereto is checked by shutting the valve m.
The waste heat from the furnace a, can be utilized for the beating of water and
generating steam to be used in the bakehouse or other parts of the premises, by
placing a high pressure boiler o, at the back of the furnace a, as represented at
figure 4, or the boiler or boilers may be carried round 3 sides of the furnace if
required, the bottom of the said boiler o, being level with the top of the fire bars p.
This high pressure boiler o, can be connected by means of flow and return pipes in
the usual way to an adjoining steam recipient, which is partly filled with water
supplied by an injector or its equivalent, and having glass water gauge, pressure
gauge, and other necessary fittings. From this recipient steam can be taken for all
necessary purposes by means of pipes governed by valves.
Instead of the boiler o, being used as and for the purpose herein before described,
a coil of pipes or their equivalent may be inserted in the flue or furnace and
similarly connected by means of flow and return pipes to an adjoining recipient.
Steam can then be taken from the recipient as before. The foregoing recipient, coil,
or its equivalent being well understood are not shewn upon the annexed drawings, and
need not be further referred to.
The interior of the oven is illuminated by means of a gas jet q, Figure 4, placed in
chamber, provided for that
purpose.
Having now particularly described and ascertained the nature of my said Invention
and in what manner the same is to be performed I declare that what I claim is.—
First. The improved bakers oven, heated by seperate, endless, doubled pipes b,
fitted in the sole c, of the same, each pipe b, having a cross connection d, for the
purpose of maintaining a constant circulation of water within the pipes heated by
means of the furnace a, substantially as and for the purpose specified with reference
to the annexed drawings and whereby especially a practically uniform temperature is
rapidly obtained in all parts of the said oven as set forth.
Second. The boiler o, situated at the back or carried round 3 sides of the furnace a,
for utilizing the waste heat from the same by generating steam within the boiler o,
which can be used for all necessary purposes substantially as herein before set
forth.
Dated this 14th day of Novamban 1007
DAVID MCARTHY,
Applicant.