IMPROVEMENTS IN COOKING RANGES
Year: 1880

page_text: LETTERS PATENT to David Robertson and Thomas Robertson, both of
Glasgow, in the County of Lanark, North Britain, Furnishing Ironmongers,
for an Invention of "IMPROVEMENTS IN COOKING RANGES."
PROVISIONAL SPECIFICATION left by the said David Robertson and Thomas
Robertson at the Office of the Commissioners of Patents on the 16th June
1880.
DAVID ROBERTSON and THOMAS ROBERTSON, both of Glasgow, in the County of
Lanark, North Britain, Furnishing Ironmongers. "IMPROVEMENTS IN COOKING
RANGES."
This Invention relates to certain improvements in the construction of cooking
ranges, specially designed to utilise more completely the heat of the gaseous
products of combustion which in the ordinary ranges escape at a high temperature,
and by this means render them more generally efficient in action.
The Invention consists, first, in constructing the improved ranges with a series of
two, three, or more vertical ovens on one side of the fire place, through a shallow
flue between and past the sides of which ovens the hot products of combustion are
led to the chimney; and, second, in surrounding these ovens on the sides which do
not form part of the flue with a double casing to prevent or diminish radiation of
heat;
whilst the form of fire-place or grate is also improved. The boiler and other
parts of the range on the opposite side of the fire place are formed much as usual,
with a hot plate and lifting covers for the insertion of cooking vessels, but the
ovens on the other sido are carried up to the top plate and back to the coverplates.
The flue between the ovens is formed alternately horizontal and vertical,
commencing and opening to the side of the fire-place in about a line with the hot
plate of the range, and passing horizontally between the top of the lowest oven
and the bottom of the oven immediately above; thence the flue continues vertically
past the end or side of the second oven, and horizontally between the second and
third ovens; then again vertically at the opposite end or side of the third oven,
and so on, in an undulating manner for the wholo series. The waste products of
combustion passing through and from this flue strike against a curved baffle plate,
fitted between the highest oven and top plate, so as to cause the gases to traverse

page_text: the whole upper surface or case of that oven before passing out through an outlet
in the top-plate into the chimney.
The sides of the oven which are exposed to the heat of the ascending hot waste
gases are formed as usual of thin metal, but the remaining sides of the ovens are
constructed with a double casing which may be fitted with ashes, brick-dust, or
other non-conducting substance for the purpose of preventing or diminishing
radiation of heat therefrom, excepting that side of the lowest oven which is exposed
to the fire. The doors of the ovens may also be double cased and packed with
ashes or other non-conductor.
In some cases, as when a steady heat is required, the inner shell of one or more
of the ovens may be formed of fire-brick, firo-clay, or other similar material; but
instead of constructing the ovens with a double casing, they may be made of a
single shell, or plates covered internally or externally with a lining or thickness of
fire-clay or other refractory non-conducting material.
The lowest oven is only heated on two sides, namely, that next the fire-place,
and above by the hot gases traversing the flue, but it may be further heated when
desired by a small fire-place or grate under-neath, as is common in ordinary ranges ;
but when no additional fire is necessary the lower fire-space would be formed as
an ornamental panel. The usual fire place or grate is also made much broader but
not so deep as hitherto, so that fuel is economised, and the open fire better suited
for cooking purposes.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said David Robertson and Thomas Robertson in the Great Seal Patent
Office on the 2nd December 1880.
DAVID ROBERTSON and THOMAS ROBERTSON, both of Glasgow, in the County of
Lanark, North Britain, Furnishing Ironmongers. "IMPROVEMENTS IN COOKING
RANGES."
Our said Invention relates to certain improvements in the construction of
cooking ranges specially designed to utilize more completely the heat of the gaseous
products of combustion which in the ordinary ranges escape at a high temperature,
and by this means render them more generally efficient in action.
The Invention consists, first, in constructing the improved ranges with a series
of two, three, or more vertical ovens on one side of the fire-place, through a shallow
flue between and past the sides of which ovens the hot products of combustion are
led to the chimney; and, second, in surrounding these ovens on the sides which
do not form part of the flue with a double casing to prevent or diminish radiation
of heat, whilst the form of fire-place or grate is also improved. The boiler and
other parts of the range on the opposite side of the fire-place are formed much as
usual, with a hot plate and lifting covers for the insertion for cooking vessels, but
the ovens on the other side are carried up to the top plate and back to the cove
plates.
And in order that our said Invention and the manner of performing the same.
may be properly understood, we have hereunto appended for that purpose a Sheet
of explanatory Drawings representing various modifications of our improvements
in cooking ranges which we shall now proceed to describe. In these Drawings the
same reference letters are used to indicate the same or like parts wherever shown
or repeated.
Figure 1 is a front elevation in perspective of one modification of our improved
cooking range having a vertical row of threo ovens. And Figures 2 and 3 are
respectively a longitudinal and transverso vertical section of the same taken as at
the lines 1-1 and 2-2 in cach other, while Figure 4 is a horizontal section taken as
at the line 3-3 in Figure 3; Figuro 5 is a longitudinal vertical section similar to
to Figure 2 of an arrangement of the improved range fitted with a pressure water
boiler;
and Figure 6 is a similar section showing a modified construction of the
improved range having only two ovens over each other.
Referring to the Drawings, Figures 1 to 4, the improved range is constructed
with a row of three ovens A, B, C, placed over each other, and preferably fitted
together, each complete in itself, so that they can be laid on the top of each other
without fixing down, but resting in position by their own weight, and thus
requiring no building, a flanged or grooved joint & being formed all round tho
lower edge of the front and side plates A¹, B¹, of the upper ovens A, B, to retain
those B, C, above. The shells of the ovens A, B, C, are held by a flango ď
cast or formed in the front and back plates A", B, C, a short way from
each other to leave a space between them forming a shallow flue D, extending in
breadth from front to back of the range, and which carries the hot gases or products
of combustion from the fire F through between the ovens A, B, C, to an outlet D¹
in the top plate E of the range leading into the chimney above. The flue D
between the ovens A, B, C, is formed alternately horizontal and vertical, or zig
zag, commencing and opening to the sido of the fire-place F in about a line with
the hot plate G of the range, and passing horizontally between the top of the
lowest oven A and the bottom of the oven B; immediately above thence the flue

page_text: continues vertically past the end or side of the second oven B, and horizontally
between the second and third ovens B, C; then again vertically at the opposite end
or side of the third oven C, and so on, in an undulating manner for the whole
series when their are more than three ovens. The waste products of combustion
passing, as shown by the arrows, through and from this flue D, may be made to
striko against a curved baffle plate fitted between the highest oven C and the top
plate E, so as to cause the gases to traverse the whole upper surface or case of that
oven C before passing out through the outlet D¹ in the top plate E into the
chimney.
•
The sides a, b, c, of the ovens A, B, C, which are exposed to the heat of the
ascending hot waste gases are formed as usual of a single thickness of metal, but
tho remaining sides of the ovens A, B, C, are constructed with a doublo casing
a, b, c, which are filled with ashes, brick-dust, or other non-conducting substance,
for the purpose of preventing or diminishing radiation of heat therefrom, excopting
part of that side of the lowest oven which is exposed to the fire, and which is
protected from its direct hent by means of a metal plate g and a fire-brick a¹. The
bottom of the oven A is also double cased, a lower horizontal plate a³ held by
flanges cast on the front and back plates A¹, A", being provided to retain the
ashes, brick-dust, or other non-conducting material between it and the oven A.
The double casings a¹, b², c¹, at the sides of the ovens A, B, C, aro formed by the
shells a, b, c, and by large fire-clay bricks or blocks H, H, which are let down
while the ovens are being fitted up in between flanges h, h, formed to receive them
on the front and back plates A, B, C², A, B, C, of the ovens. These fire-clay
blocks H, H, are provided also to prevent radiation of heat from the ovens, even
when the intermediate packing of brick-dust is dispensed with. Similar fire-clay
blocks H' are in like, manner fitted at the back of the ovens A, B, C, as shown
particularly in Figure 4. The double casings a, b, c, are fitted at top and bottom
with movable plates all, b, c, to retain the ashes, brick-dust, or other non-
conducting material with which they are fitted.
- The, doors A, B, C, of the ovens may also be double cased, and the
casings packed with ashes, brick-dust, or other non-conducting material, or small
flanges or flanged brackets h may be formed or fitted on the doors A2, B2, C³,
into which fire-clay bricks or blocks H" may be fitted, as indicated in dotted lines
in Figure 4.
The ovens A, B, C, are ventilated in the usual way by means of an opening i
near the upper back part of each, covered by a sliding plate actuated by a rod and
handle or knob I passing out through the front plates of the grate, the sliding plate
having an arched covering plate i¹ over it opening to the flue D.
The draught through the fluo D is regulated by a damper J fitted in the
outlet D' and operated by a rod and handle or knob J¹ passing out through the
front plate C. Another damper plate K with its knob K¹ is fitted between tho
fire place F and the flue D, which may be drawn out to prevent the hot gases
passing direct into the flue D. The products of combustion then pass along a
Blue L formed between the hot-plate G and the top of the water boiler M, as shown
in Figures 2, 3, and 4, and passing round the covered inlet opening M' for filling
the boiler, the gases pass into the flue D near the back of the range through an
opening which is closed when the damper K is pushed back. Instead of the
open boiler a high pressure boiler may be fitted in the back part of the range
with a flue pipe fitted to the back of the covings. This damper K thus admits of
the full heat of the fire F being applied direct to heat the ovens A, B, C, or to
heat the boiler L and cooking vessels placed in or over the usual openings in the
hot plate fitted with lifting covers G. Cleaning doors N opening to the flue D
are provided for cleaning deposits of soot on the outer surface of the oven shells
a, b, c, theso doors N being specially fitted, practically air-tight, and securely held
by swivelling catches n outside. With this arrangement of flue and fittings, a
very strong draught is secured, and the ovens retain the heat most effectually.

page_text: The usual sliding dampers O in the top plate are provided, as also plate rack P
and other usual fittings.
In some cases, as when a steady heat is required, the shell of one or more of
the ovens may be formed of fire-brick or other similar material in one piece.
Instead of constructing the ovens with double casings, as shown, the may be made
of a single shell or plates covered internally or externally with a lining or thickness
of fire-clay or other refractory non-conducting material. The firo-place or grate
is also made much broader, but not so deep as hitherto, so that fuel is economised,
and the open fire better suited for roasting and other cooking purposes. The
lowest oven is only heated on two sides, namely, that next the fire-place and above,
by the hot gases traversing the flue, but in cases where the ovens are fitted apart
from the range they are heated by a small fire-place or grate underneath.
This
The modification of our improved range, shown in Figure 5, only differs from
that described in having a pressure water boiler M fitted in it instead of the
ordinary open boiler M, shown in Figure 1 to 4. The connections for the inlet
and outlet of the water are at the back of the boiler and are not shown.
boiler M¹ rests on the fire-grate Fat the back, but is cut away the full extent
backwards of the fire to form a fluo or inlet L' to the flue D beneath it, and thus
heat both the boiler and ovens with one flue. A small space is also left above the
boiler M' between it and the hot plato G for the passage of smoke from the top
part of the fire. A flange is formed on the front plate A on which the lower edge
of the boiler M' rests to keep it in position. In this construction of the improved
range the fire-place F is removed to one side to the extent of the broadth of the
boiler M².
In Figure 6 a modification of our improved range is shown having only two
oven A, B, but otherwise differing little from the modification shown in Figure
1 to 4. The cove plates Q are shown carried up to the top plate, but in this form
of the range a short height of skirting only may be fitted at the back.
A chimney D' carries the waste gases from the flue D to the chimney, a damper J
being provided. This range is shown fitted with an open boiler Mill, but it may
have instead a pressure water boiler M³, as indicated by the dotted lines, in which
case the firo-grate F would be removed to a corresponding extent to the opposite
side.
Having thus described the nature of our Invention and the manner of per-
forming the same, we have to state that we do not confine ourselves to the
precise details herein described or delineated, but what we believe to be novel and
original, and therefore claim as the Invention secured to us by the herein-before in
part recited Letters Patent is,—
First. The general construction and combination of the parts of a cooking
rango, in which the hot products of combustion are carried by an undulating
fluo D through between a series of ovens (as A, B, C) ranged vertically over each
other, and provided with double cased sides a, b, c, filled with ashes, brick-dust, or
other non-conducting material, and having fire-bricks or slabs inserted to prevent
radiation of heat from the sides of the ovens, all substantially as and for the
purposes herein described in reference to the accompanying Drawings.
Second. The arrangement and disposition in a cooking range of a series of ovens
over each other, cased or protected with fire-bricks, fire-clay, or other refractory
material, or formed of such material, the range being fitted either with or without
an open or pressure water boiler heated by the hot firo gases passing through a
flue below or over it, and ascending through between the ovens to the chimney,
all substantially as and for the purposes herein described in reference to the
accompanying Drawings.
Third. In a cooking range having the ovens disposed vertically over each other,
the fitting or constructing of such ovens with a double casing a¹, b', c¹, filled with
ashes, brickdust, or other non-conducting material on the sides not exposed to the
heat of the fire gases passing through an ascending flue, and with or without the

page_text: addition of fire-brick linings or walls H, H, to prevent outward radiation of heat
from the fluo, all substantially as herein described in reference to the accompanying
Drawings.
In witness whereof, I, the said David Robertson, on behalf of myself and
the said Thomas Robertson, have hereunto set my hand and seal, this
Twenty ninth day of November, in the year of our Lord One thousand
eight hundred and eighty.
Witness,
WALLACE FAIRWEATHER, C.E.,
Of W. R. M. Thomson & Co.,
Patent Agents,
Glasgow.
D. ROBERTSON. (Ls.)