Improvements in Ovens for Baking Bread and for similar purposes.
Year: 1894

page_text: Date of Application, 18th Jan., 1894
Complete Specification Left, 17th Nov., 1894-Accepted, 22nd Dec., 1894
PROVISIONAL SPECIFICATION.
Improvements in Ovens for Baking Bread and for similar purposes.
WILLIAM KING BAKER and GEORGE SAMUEL BAKER both of 58 City Road,
London E.C. Engineers, do hereby declare the nature of this invention to be as
follows:-
An improved method of constructing bakers' ovens whereby there is greater
economy of heating and more regularity and simplicity of working with power to
regulate the heat to suit the various requirements.
Our invention relates to that class of ovens in which the combustion chamber or
furnace is separate from the oven or baking chamber.
In carrying out our invention we construct the furnace chamber immediately
below and extending under the whole or nearly the whole of the oven chamber, the
oven sole being carried upon piers built up from the bottom of furnace chamber.
The furnace itself with ashpit, fire-bars doors, and fittings may be placed so as to
be fired from the front, back or either side of oven as is most convenient and is'
directly open to the rest of the furnace chamber along its back end.
For certain classes of work we construct a platform between the oven chamber
sole and bottom of furnace carried by the piers supporting sole but detached from
the side walls of oven, the width of space varying according to the goods generally
to be baked.
From the two front corners of furnace chamber we construct two large flues
leading directly into the oven chamber above, with appropriate dampers and frames
for internally heating the oven chamber with hot air from the furnace, while at the
back of oven chamber we construct two flues side by side operated by one double
damper in such a manner that when the damper is partly drawn out one flue is put
in open communication with the furnace chamber below and allows the heated air
from furnace to circulate through the oven chamber and back to furnace again or if
the damper be pulled out to its full extent both flues are opened and the second one
is put in communication with the chimney flue to form a forced draught for
producing a "flash" heat in the oven by quickly drawing the heated air from
furnace through the front flues and out at back of oven.
In the front or some other wall of oven as most convenient we build in a door
and frame just below the level of bottom of oven sole for admitting cold air when
required for reducing "bottom" heat or heat of the sole of the oven.
In one or both side walls of oven we form flues from furnace chamber which are
gathered together above the oven, controlled by means of one damper and then
carried forward to chimney flue for smoke exit.
We form the furnace frame and doors in such a manner that when the furnace
intermediate and outside doors are closed there is an open airway under the outer
door, over the intermediate door and under the furnace door to the ashpit for
draught to firebars, the air being heated in its passage and ensuring more complete
combustion.
A small flue or two flues also formed from one or both sides of the furnace frame
and gathered up to connect with the chimney flue for carrying off the heated air
which might otherwise escape back into bakehouse when the heat dampers of oven
are closed. We further provide that a hinged door or other arrangement may be
operated to close the exit of air up this aforesaid ventilating flue from furnace frame

page_text: when it is desired to heat up the oven or vice versa to close up all ingress of air to
furnace and open the small furnace frame ventilating flue.
Dated this Seventeenth day of January 1894.
We, WILLIAM KING BAKER and GEORGE SAMUEL BAKER, Engineers of
58 City Road in the County of London, 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 :-
Our invention has relation to improvements in ovens for baking bread &c.
In the accompanying drawings
Fig. 1 is a longitudinal section on the line A. B.
Fig. 2 is a transverse section on the line C. D.
Fig. 3 is a transverse section on the line E. F.
Fig. 4 is a transverse section on the line G. H.
Fig. 5 is a transverse section on the liue J. K.
Fig. 6 is a plan through the line L. M.
Fig. 7 is a plan through the line N. O.
Fig. 8 is a plan through the line P. Q.
The letters in each figure refer to the same parts.
Referring to these drawings our oven is constructed with the furnace chamber (a)
immediately below and extending under or nearly under the whole of the oven
chamber the ovensole being carried upon piers (p) built up from the bottom of the
furnace chamber (a). The furnace itself (a) with ashpit (a) firebars (a³)
doors (a a a) and fittings may be placed so as to be fired from the front, back or
either side of oven as is most convenient, and is directly open to the rest of the
furnace chamber (a) along its back end, side or sides to suit position and size of
oven.
For certain classes of work we construct a platform (p') (see Fig. 4) between
oven chamber sole (s) and bottom of furnace chamber (a) carried by piers (p)
supporting sole (s) but detached from the side walls of oven (w), the width of space
varying according to the class of goods generally to be baked. This platform
extends over the furnace chamber and is for the purpose of preventing too much
heat on the oven sole.
From the two front corners of furnace chamber (a) we construct two large.
flues (d) leading directly into the oven chamber (e) above, with appropriate dampers
and frames (d) for internally heating the oven chamber (e) with heating gasses
from combustion of fuel in furnace (a¹). At the back of oven chamber (e) we
construct two flues (f and f¹) operated by one double damper (f) in such a manner
that when the damper (*) is partly drawn out, the flue (¹) is put in open com-
munication with furnace chamber (a) below, and allows the heated gasses from
furnace to circulate up through the flues (d) through (✓³) to furnace (as
shown by arrows), the most highly heated gasses leaving the top of the furnace
chamber by flue (d) and ascending to oven chamber, the colder air of oven chamber
descending through flue (f) to the cooler part of furnace chamber at the back,
thus establishing a circulation of heated gasses between furnace chamber and oven
chamber. When the damper (f) is drawn fully open it places the flue (f) in
communication with the chimney (v) thus establishing a forced draught and causing
the oven to heat up quickly as required for flash heat.

page_text: In the front or some other wall of oven, as most convenient, we build one or
nore doors (h) or some other suitable device, below the level of bottom of oven sole
for admitting cold air when required for reducing "bottom heat" or heat of the
sole of the oven.
In one or both side walls of oven we form flues (7) from furnace chamber (a)
which are gathered together above the oven into a crown heating chamber (*) the
exit of which is regulated by means of a damper (1).
We form the furnace frame (a) and doors (a", a, a) in such a manner that when
the furnace door (a) intermediate door (a) and outside door (a) are closed there
is an open airway under the outer door (a) over the intermediate door (a) and
under the furnace door (a) to the ashpit (a) for draught to fire, the air being
heated in its passage and ensuring more complete combustion at the same time
keeping the outer door cool.
A small flue or two flues (m) are also formed from one or both sides of the
furnace frames (a") and gathered up to connect with the chimney flue (v) to carry
off the sulphurous fumes or smoke which might otherwise escape back into the
bakehouse when the heat dampers of oven are closed. We further provide that a
hinged door (not shown in drawings) or other arrangement may be fixed at any
convenient point and operated to close the exit of air up the aforesaid ventilating
flue (m) from furnace frame (a) should it be desired.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we have to state that
we do not restrict ourselves to the precise details herein described or shown.io
the accompanying drawings but what we claim for our Letters Patent as novel is
1. In ovens for baking purposes, the arrangement and construction of the furnace
with furnace chamber directly open to furnace, extending under the whole or
nearly the whole of the oven sole with or without a platform between the oven
chamber sole and bottom of furnace, detached from the side walls of oven, leaving
an air space between the platform and bottom of oven sole by means of uplet
flue (d) and return flue (¹) and vent flue (f) substantially as herein described and
illustrated in the drawings.
2. In ovens for baking purposes the construction and combination of one or more
flues leading directly from the furnace chamber to oven chamber and having one or
more flues leading out of the oven chamber, one being connected to furnace
chamber below and the other to the chimney, the two operated by one double
damper in such a manner as herein described and illustrated by the drawings.
3. In ovens for baking purposes the construction and arrangement of a flue or
flues in combination with the furnace doors and frame in such a manner and for
such a purpose substantially in the manner herein described and illustrated by the
drawings.
4. In ovens for baking purposes, the combination of a top heating chamber over
the crown of oven chamber with one or more flues leading from the furnace chamber
(as in Claim No. 1).
5. In ovens for baking purposes the general arrangement or construction and
combination of the parts substantially in the manner herein described and illustrated
by the drawings.
Ny 201
WILLIAM KING BAKER.
GEORGE SAMUEL BAKER.