Improvements in Ovens for Baking or Roasting.
Year: 1894

page_text: Date of Application, 21st Apr., 1894-Accepted, 9th June, 1894
COMPLETE SPECIFICATION.
Improvements in Ovens for Baking or Roasting.
1, JAMES BLATCH Cox Engineer &c., of Shelton, Torquay, 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 relates to a construction of ovens of the kind described in the
Specification to my Patent No. 9120 of 1890, in which the hot combustion gases
from a furnace are made to ascend by pipes or flues to the top part of the chamber
in which the ovens are situated, and then descend again in contact with the ovens
in order to escape through the opening of the discharge flue at the bottom of the
chamber.
According to my present improvements I so construct said ovens and the flues
and valves of or dampers controlling them that the hot combustion gases can be
directed at will so as to either heat all the ovens equally or to heat some of them
more than the others, or to heat a single oven either equally at top and bottom, or
to a greater extent either at top or at bottom.
For these purposes I construct the ovens as I will describe with reference to the
accompanying drawings, in which Fig. 1 shews a vertical section of a chamber or
casing containing for example, two ovens.
A is the casing, which may either be of brickwork or of double metal walls
packed with non conducting material such as silicate cotton &c.
BB' are two ovens, separated from each other by a floor C; E is the furnace
which may be placed at either end or side, or underneath, and from which the hot
combustion gases pass through flues beneath the floor E' to the lower ends of
flues DD that extend up to near the top of the upper chamber containing the
oven B' and that have openings G just below the floor C.
These openings are provided with valves or dampers arranged in such manner
that they may either leave the openings entirely free, in which case the hot gases
will pass into the lower chamber through these openings and through the upper
open ends of the flues into the upper chamber to an equal extent; or the valves
may be made to partially or wholly close the openings G, in which case either the
greater part or the whole of the gases are made to pass into the upper chamber,
thus either heating the oven B' only or heating it to a greater extent than the
oven B. Lastly the valve can be moved so as to close the passage to the upper
chamber either wholly or partially, so that the hot gases will either wholly or
mostly pass into the lower chamber. From the bottom of the lower chamber
discharge flues F pass up to the main discharge flue I at top, and from the bottom
of the upper chamber other discharge flues F also pass up to the main flue I, the
lues F F being provided with dampers at H for starting the draught.
From this arrangement it will be seen that each oven can be heated inde-
pendently of the other to any desired extent, the hot gases in entering either the
pper or the lower chamber being made to travel downwards over the surfaces of
he ovens before escaping through the flues F or F' to the chimney.
Fig. 5 shews by way of example a form of valve for regulating the passage of
he hot gases in the before described manner.

page_text: The opening G of the flue D is provided with a hinged flap valve K which cau
he moved by the rod L either into the vertical position shewn at 1, in which it
allows of the free passage of the gases to the top compartment, preventing them
from passing through the opening G into the lower chamber, or by more or less
closing the valve, as in the dotted position 2, it will either restrict or cut off such
passage of the gases from the top compartment, or by moving the valve into the
position 3, it will allow of the free passage of the gases to both chambers with the
power to regulate the quantity passed to the lower one.
Fig. 2 shews a vertical section of a modified construction in which the separate
discharge of the gases from the upper chamber into the main flue is dispensed
with, the gases being made to pass from the bottom of the upper chamber through
flues F down into the lower chamber, where they escape together with the gases
from this chamber through the flue F.
Fig. 3 shews another modification which only differs from Fig. 1 in that the
discharge flues F, which in this case are shewn built in the brickwork A, are
common to both the chambers, the lower one communicating therewith at H while
the upper one communicates with it at H', and if necessary also at H³, these
openings being provided with suitable regulating dampers.
It will be evident that in each of the above constructions each compartment of
the casing A may contain more than one oven, arranged either side by side or one
above the other; also, instead of only two compartments any greater number
may be employed.
Fig. 4 shews a construction in which a single oven B is contained in the
chamber A, this being divided by the bottom of the oven into an upper and a
lower compartment.
In this case the inlet flues DD open into the upper compartment, and have
openings G provided with valves such as before described, whereby the hot gases
can either be admitted wholly or partially into the lower compartment, or wholly
or partially into the upper compartment thus heating the oven either from above
or from below or both above and below.
The discharge flues F have openings at H from the lower compartment and
at H' from the upper one. Or there may be separate discharge flues from each
compartment.
It will be understood that the above described improved constructions are
equally applicable to ovens working on the continuous system, that is to say, in
which the oven is of some length and the goods are made to travel slowly along
them on travelling trays or platforms.
Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. Constructing ovens with two or more separate compartments, each of which
contains one or more ovens, the hot combustion gases being made to enter the
same through flues with openings and valves or dampers so arranged that the gases
can either be admitted equally to both or all compartments or that their entrance
into one or more compartments is more or less restricted or entirely cut off, while
the discharge of the said gases is made to take place from the bottom of each
compartment either into separate flues or into a flue common to both or all, or the
discharge is effected from the bottom of the upper compartment into the lower one
and thence into the chimney flue, substantially as described.
2. Constructing an oven enclosed in a chamber in such manner that the
chamber is divided horizontally into two compartments, the bottom part of the
oven being in the lower compartment while the upper part is in the upper
compartment, the inlet flues for the hot combustion gases being so arranged and
controlled by means of suitable valves or dampers that the gases can either be
admitted simultaneously into both compartments, or can have their admission to

page_text: the one or other compartment restricted or entirely cut off, while the discharge of
the said gases is made to take place from each compartment either through a
common flue or through separate flues, substantially as described.
Dated this 21st day of April 1894.
ABEL & IMRAY,
Agents for the Applicant..