Improvements in Stoves and Cooking Ranges.
Year: 1888

page_text: Date of Application, 3rd July, 1888
Complete Specification Left. 3rd Apr., 1889-Accepted, 22nd June, 1889
PROVISIONAL OF ECIFICATION.
Improvements in Stoves and Cooking Ranges.
I, MALCOM COCKBURN trading under the style or firm of M. Cockburn & Co.
at Gowanbank Iron Works, Falkirk, in the County of Stirling, North Britain
Ironfounder do hereby declare the nature of this invention to be as follows:-
This invention relates to stoves and cooking ranges, and has for its objects:
1st. to adapt them for alternate use with an open top to the fire or a closed one as
required.
2nd. to control the currents of heat which circulate around each oven: and
3rd. to regulate and control the flow of heat through all the flues thereof.
In carrying out the first named object of my invention I attach an upright metal
fine box behind the stove (or cooking range) which box is provided at the front
thereof with a limited aperture, for flue purposes, the lower part of which (aperture)
is covered, or otherwise occupied, by a pivotted flue pipe, and the upper part thereof
by a swinging shutter or flap. When the top of the fire is closed with its cover
the said pivotted flue pipe is (enclosed) in a vertical position, within the first named
upright metal flue box, where its exposed surface is in line with before named swinging
shutter the whole of the first named flue aperture being closed thereby, & when the
pivotted flue pipe is thus enclosed within this back flue box its open ends are in
vertical positions (one with the other) and afford a free course for the operation of the
Boiler (and other) fluos associated therewith.
In order to use the range with an open fire the flue pipe (which is pivetted at its
lower front edge to a metal framework) is pulled forward at the top, (the swinging
shutter yields to afford it free passage) and lowered in its radial course until the part
which was uppermost reaches and resis upon the hole when its open ends afford a flue
communication between the back of the fire and the first named upright metal flue
box: the fire cover being pushed backwards, or otherwise removed, the range is in
every sense an open fire" one. The swinging shutter and the pivotted flue pipe are
so adjusted within the front aperture of the vertical flue Box that whether the pivotted
flue pipe rests upon the hob or within this back flue box the portion of the front
aperture which is above it is completely covered by the swinging shutter.
ແ
When it is desired to use the range with a closed fire, the cover thereof is drawn
forward (or otherwise re-placed) upon it and the flue pipe is raised up from its position
on the hob and revolved upon its pivots into its upright position within the back flue
box; the swinging shutter yielding as far as necessary to admit it, and then assuming
its vertical position as before.
In order to obviate the removal or lifting away of the fire cover in the foregoing
operations I have adopted certain mechanism described and contained in the patent
which is numbered 13194 entitled "Improvements in Cooking Ranges" and bearing
date Novr. 2nd 1885 and which mechanism consists of a loose, complex, hoh piece,
coupled by link appliances to the fire cover and curved or sloping guides or flanges
within the upright metal flue box before named. By these contrivances I am enabled
to remove the said loose hob piece from its horizontal position and tilt it up into the
said flue box where it remains in a more or less erect position without obstructing
either the boiler flue or any other, and when the fire cover is drawn forward over
the fire the link appliances which connect these two hob plates together servo to
restore this tilted member to its horizontal position before the pivotted flue pipe, in its
turn, is tilted up into the flue box.
In carrying out my second named object I construct a forked tubular metal
flue behind each or either oven of my cooking range and make it accessible for
cleaning and general flue purposes, at the upper and lower parts thereof. This fire

page_text: is wholly beneath the hob and not behind the cove pintes skirting or upper back frame
work of the oven. One portion of the forked flue pipe is vertical and extends
from the under side of the hob downwards to a convenient point beneath the oven
and on that margin which is nearest to the fire back. The other portion of the
forked flue pipe traverses the back of the oven diagonally: it is united to the vertical
portion of the flue pipe at the upper part of the latter and descends obliquely across
the back of the oven to that lower corner thereof which is farthest from the fire back
where it is provided with a limited aporture connecting it with the bottom and side
fines of the oven-at its junction with the vertical portion it has another aperture
and the vertical part of this flue has an aperture at the bottom (which associates it
with the fine spice beneath the oven) and anothor at the top which affords a vent into
the principal (central) fine above the hob of the range.
The object I have in view in constructing this back oven flus as described is a
twofold one-namely heating the oven alternately at the top or bottom equally or
unequally as required and conveniently cleaning out the flue.
Access to the vertical and diagonal portions of this forked flue is easily obtained
(for sweeping and cleaning purposes) at the top by any ordinary means—either by
the removal of a cover plate from the hob or by opening or temporarily removing
some portion of the convertible fluo mechanism associated with the fire back of the
range.
The soot which is swept from the diagonal portion of the flue falls naturally lo
its lowest point where it is easily cleaned out from beneath the oven in the usual
way.
The manner in which I control the flow of heat around each oven by the forked
flue mechanism just described is as follows:-within the vertical portion of this forked
flue I construct a double damper the two principal portions of which are more or
less of a helt shape, belting the inner portions of the vertical flue nearest to the
apertures which communiento with the other oven flues. The upper and lower
apertures being some distance apart the two said bolt shaped dampers are united by
au inflexible rod or other agent so that the two belts may be raised or lowered
simultaneously the lower belt is for covering the bottom aperture and the upper one
covers the top one. My desire is to cover the one wholly when the other is fully open
or partially open each as required. When only the lower port hole is open the
whole of the heat which proceeds from the fire to that oven is obliged to obtain vent
at this part as tho aperture at the upper end of the diagonal tube is closed and the
heat within it is a stagnant atmosphere:--when this double belt damper is moved so
as to close the lower aperture the upper one is simultaneously opened and the
currents of heat which proceed from the top and bottom of the fire and flow over
and under the oven unite (and find escapement) at the lower end of the diagonal
tube and proceed thence, uninteruptedly into the main (central) flue above the
range.
When the upper and lower apertures are simultaneously and partially open there is
an escapement afforded at each point for the currents of heat passing over and under
the oven.
In further explanation of this provision it may be stated that when the lower
port hole (only) is open the fresh fierce heat which proceeds from the lower part
or sides of the fire (usually through a grated fire chock adjoining the oven side)
obtains immediate escapement therent without passing underneath the whole surface
of the oven bottom and the current of heat which proceeds from the top of the fire,
across the top of the oven, down the farthest side thereof, and underneath the oven is
materially diminished in its intensity before it unites with the former current at the
said aperture and the bottom of the oven is likely to be less intensely heated than the
top of it. On the other hand when the bottom aperture is closed and only the top
one open the fierce fresh heat which proceeds directly from the fire to the under-side
of the oven, traverses the whole of the oven bottom before it unites with the other
currents at the lower end of the dingonal flue.
My third named object is but an enlargement of my last named one.

page_text: In some cases where I find it inconvenient to apply the last named provisions for
regulating and controlling the course pursued by the currents of heat proceeding
from the fire to each oven (or boiler) I employ double dampers of a somewhat
different construction and placed in other parts of the same flues or in the main
(central) flue of the range, thus, when for convenience I effect this damping control
in the main central flue of the range-I construct therein one or more sets of twin
pivotted dampers each pair of dampers having only one spindle and each damper
having an indpendent action thereon. Each pair of pivotted dampers when confined
in a narrow flue space assume a more or less V form the spindle thereof being located
at the point of their union with each other-when two pairs are employed they unito
in the form (more or less) of a W the two lowest points thereof represent the locality
occupied by each spindle. On the right and left of each spindle the flue space is
formed into separate chambers by such means as a midfeather or division plate which
gives to cach pair of such pivotted dampers a form resembling a Y and (in the case
above referred to) of two contiguous ones thus Y. Y. These figures fairly serve to
illustrate certain attitudes of my twin pivotted dampers.
It will readily be understood that the two (or four) leaves of these damper sets
when placed within a (principal) flue space may be made to close it completely and as
each or any one of them is revolved upon its spindle one or other of the flues
associated therewith will he opened or closed thereby. 1 have so constructed theso
dampers that any one only of their constituent flaps may be folded completely over
until it lies against its mate or each flap may be revolved within one half only of its
orbit and is then in contact with its mate. By means of such a complete damping
mechanism as that just detailed it will be seen that I can regulate the currents of heat
which flow through any or all of the flues of my cooking range in any manner
required.
The flue damping provisions herein described in connection with the oven and
Boiler flues of a Cooking range are equally applicable to a stove or heating apparatus
which is not designed for cooking purposos and it will therefore be understood that
the pivotted and other double damping fluo mechanism berein described are intended
for combination with apparatuses for heating churches and other large structures, and
for general trade purposes where a two, three or four-way flue requires to be con-
trolled in such a manner as aforesaid.
COMPLETE SPECIFICATION.
Improvements in Stoves and Cooking Ranges.
I, MALCOM COOKBURN trading under the style or firm of M. Cockburn & Co., at
Gowanbank Ironworks Falkirk, in the County of Stirling, North Britain, Ironfounder
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:
This invention relates to Stoves and Cooking Ranges and has for its objects,
1st to adapt them for use, alternately, with an open top to the fire or a closed one
as required.
2nd to control the currents of heat which circulate around each oven; and,
3rd to regulate and control the flow of heat throughout all the flues thereof.
I effect these objects by means of the mechanism which is illustrated in the following
drawings, in which
Fig. 1 is a view in perspective shewing the metal flue box, for use in connection
with my combined open
and close fire mechanism, in its position behind a covering
plate.
Fig. 2, is a view in perspective of my combined open and close fire appliances,
1

page_text: #ig. 5. 18 a view in perspective of my combined open and close fire appliances
when open.
Fig. 4, is a side elevation in section of my combined open and close fire appliances
when closed.
Fig. 5, is n side elevation in section of my combined open and close fire appliances
when open.
Fig. 6, is a view in perspective of my tumbling metal flue pipe, as shown in
figures 2, 3, 4 and 5,
Fig. 7, is an illustration in perspective, as seen from the back, shewing the external
appearance of an oven furnished at the back with my improved (forked) flue.
Fig. 8, is an illustration in perspective shewing the external appearance (as seen
from the back) of a double oven Rango which is furnished with my improved forked
flues enclosed within a chamber behind each oven.
Figs. 9 to 15 are views in section, elevation and perspective, illustrative of my
improved forked flue for heating ovens.
Figs. 16 to 18 are views in section, elevation and perspective, illustrative of my
forked oven flue and other (associate) mechanism.
Figs. 19 and 20 are views in elevation and section of my twin, helt (or tube shaped)
damping mechanism.
Figs. 21 to 23 are additional views in elevation and section of my improved oven
flues and dumping mechanism.
Fig. 24 is an interior view, in perspective, shewing my V and Y shaped, twin,
pivolted dampers within an upright flue.
Figs. 25 to 29 are internal and external views in perspective of my V, W, Y and
double Y shaped damping mechanism.
Figs. 30 to 34 are views in perspective of parts only of my fine damping and
ventilating mechanism.
In carrying out the first named object of my invention I autach an upright metal
flue box behind the stove (or cooking range)" which box is furnished at the front
thereof with a limited aperture, for flue purposes, the lower part of which (aperture)
is covered or otherwise occupied by a pivotted flue pipo and the upper part thereof
by a swinging shutter or flap. When the top of the fire is closed with its cover the
said pivotted flue pipo is (onclosed) in a vertical position, within the first named
upright metal flue box where its exposed surface is in line with the before named
swinging shutter the whole of the first named fine aperture being closed thereby and
when the pivotted flue pipe is thus enclosed within this back fluo box its open ends
aro in vertical positions (one with the other and afford a free course for the operation
of the boiler and other flues associated therewith.
In order to use the range with an open fire the flue pipe (which is pivotted at
its lower front edges to a metal framework) is pulled forward at the top (the swinging
shutter yields to afford it free passage) and lowered in its radial course until the part
which was outermost roaches and rests upon the hob, when its open ends afford a fluo
communication between the back of the fire and the first named upright metal flue
box, the fire cover being pushed backwards, or otherwise removed, the range is in
every sense an open fire one. The swinging shutter and the pivotted flue pipe are so
adjusted within the front aperture of the vertical flue box that whether the pivotted
flue pipe rests upon the hob or within this back flue box the portion of the front
aperture which is above it is completely covered by the swinging shutter.
When it is desired to use the range with a closed fire, the cover thereof is drawn
forward (or otherwise replaced) upon it and the flue pipo is raised up from its
horizontal or sloping position on the hob and revolved upon its pivots into its
upright position within the back fine box: the swinging shutter yielding as far as
necessary to admit it and then assuming its vertical position, as before.
In order to obviate the removal or lifting away of the fire cover in the foregoing
operations I have adopted certain mechanism described and contained in the patent
which is numbered 13194 entitled improvements in cooking ranges and bearing dute
Nov. 2nd 1885 and which mechanism consists of a loosu hob piece, coupled by

page_text: link appliances to the fire cover, and curved (or sloping) guides or flanges within
the upright metal flue box before named by these contrivances I am enabled to
remove the said loose hob piece from its horizontal position and tilt it up into the
said flue box, where it remains in a more or less erect position without obstructing
either the boiler flue or any other and when the cover is drawn forward over the
fire the link appliances which connect those two hob plates together serve to restore
this tilted member to its horizontal position before the pivotted flue pipe in its
turn is tilted up into the flue box.
In carrying out my second named object 1 construct a forked tubular metal flue
behind each or either oven of my cooking range and make it accessible for cleaning
and general flue purposes at the upper and lower parts thereof. This flue is
wholly beneath the hob and not behind the cove plates, skirting or upper back
framework of the oven. One portion of the forked flue pipe is vertical and extends
from the underside of the hob downwards to a convenient point beneath the oven and
on some part thereof which is nearest to the fire back. The other portion of the
forked flue pipe traverses the back of the oven diagonally: it is united to the vertical
portion of the flue pipe at the upper part of the latter and descends obliquely across
the back of the oven to that lower corner thereof which is farthest from the fire
back where it is provided with a limited aperture connecting it with the bottom and
side flues of the oven: at its junction with the vertical portion, it has another aperture
and the vertical part of this Hue has an aperture at the bottom (which associates it
with the flue space beneath the oven) and another at the top which affords a vent
into the principal (central) flue above the hob of the range.
The object I have in view in constructing this back oven flue as described is a
twofold one, namely, heating the oven alternately at the top or bottom, equally or
unequally as required, and conveniently cleaning out the flue.
Accoss to the vertical and diagonal portions of this forked flue is easily obtained
(for sweeping and cleaning purposes), at the top, by any ordinary means-either by
the removal of a cover plato from the hob or hy opening, or temporarily removing,
some portion of the convertible flue mechanism associated with the fire back of
the range.
The soot, which is swept from the diagonal portion of the flue, falls naturally to
its lowest point where it is easily cleaned out from beneath the oven in the
usual way.
The manner in which 1 control the flow of heat around each oven by the forked
flue mechanism just described is as follows:- within the vertical portion of this
forked flue I construct a double damper the two principal portions of which are more
or less of a belt shape, lining the inner portions of the vertical flue nearest to the
apertures which communicate with the other oven flues. The upper and lower
apertures being some distance apart the two said belt shaped dampers are united by
an inflexlible rod, or other suitable agent so that the two belts may be raised or
lowered simultaneously the lower belt is for covering the bottom aperture and the
upper one covers the top one. My desire is to cover the one wholly when the other
is fully open or partially open each, as required; when the lower port hole only is
open the whole of the heat which proceeds from the fire to that oven is obliged to
obtain vent at this part as the aperture at the upper end of the diagonal tube is closed
and the heat within it is a stagnant atmosphere-when this double-belt damper is
moved so as to close the lower aperture the upper one which opens into the diagonal
flue is simultaneously opened and the currents of heat which proceed from the top
and bottom of the fire and flow over and under the oven unite (and find escapement)
at the lower end of the diagonal tube and proceed thence uninterruptedly across the
top of the vertical portion of the forked flue into the main (central) flue above the
range. When the upper and lower apertures are simultaneously and partially open
there is an escapement afforded at each point for the currents of heat passing over
and under the oven. It may be stated here that in some cooking ranges all the heat
passes over the top of the oven but in others a portion passes under the oven directly
from the fire without traversing the top of it first.

page_text: In further explanation of this provision it may he stated that when the lower port
hole (only) of the vertical flue is open the fresh fierce heat which proceeds from the
lower part or sides of the fire (usually through a grated fire cheek adjoining the oven
side) obtains immediate escapement thereat without passing underneath the whole
surface of the oven Lottom and the current of heat which proceeds from the top of
the fire across the top of the oven down the farthest side thereof and underneath the
oven is materially diminished in its intensity before it unites with the former current
of the said aperture and the bottom of the oven is likely to be less intensely heated
than the top of it. On the other had when the bottom aperture is closed and only
the top one open the fierce fresh heat which proceeds directly from the fire to the
under side of the oven traverses the whole of the oven bottom before it unites with
the other currents at the lower end of the diagonal flue.
I also find it more convenient, at times, to operate the twin belt-shaped dampers
within the vertical flue behind the oven by means of a rod or spindle protruding
through the oven front plate instead of doing it as previously described by a handlo
protru ling upwards through the hob and for this purpose 1 employ a spille
resembling one which is in very frequent use amongst cooking range makers for
revolving flap or damper between the fire and the oven top and which spindle is
often fitted upon, or near, that margin of the oven top which is nearest to the fire.
By connecting this spindle with the twin bolt-shaped dampers in the manner herein
after described I am enabled to open and close either the top or bottom apertures
easily without interfering with any vessels which may be upon the hob.
In the accompanying drawings have shown a descending fluo which is
frequently employed by cooking range makers in combination with their ranges. It
is formed between the fire and the oven and can be closed or opened at the top by
means of a flap or hinged damper connected with that front part (only) of the oven
top which is nearest to the fire. By lengthening the spindle of this said damper and
extending it to the flue behind the oven I am enabled to operate the twin belt shaped
dampers by its agency; either by uniting the spindle and flap rigidly together and
causing them to act simultaneously, or by affording the flap and spindle separate
actions similarly to the V and W shaped dampers shown and described herein.
Instead of constructing the forked, two-way flue behind the oven as previously
described I sometimes form it by means of division plates enclosed within a fluo
chamber which covers one whole surface of the oven; thus, I place one or more
diagonal division plates within the said chamber and thereby cause the heat to travel
diagonally to the upper part of the vertical flue containing the twin bolt shaped
dampers. The lower portion of this flue chamber is open at the bottom where it
unites with the flue space beneath the oven and receives therefrom a degree of
stagnant heat which serves to keep the whole back part of the oven more uniformly
heated than is effected by the superalded crutch or forked Ane previously described.
When the fire is first lighted in my cooking range, or fresh fuel put on it, and
the cover replaced, I find that the smoke has a tendency to exude through the
orovices around the hob platos instead of passing freely from the top of the fire
to the proper outlets, and to remedy this evil (which is a very common one in
close fire ranges) and (in order) to afford an escapement for the smoke at, or
conveniently near to, the fire back, I have provided a "hit and miss" grating or
dampor above the oven.
It will thus be seen that by means of the several apertures to the forkod flue
and the raising or lowering of the twin (belt-shaped) dampers within its vertical
portion, that the currents of heat proceeding over the top of the oven and underneath
it can be allowed to find oxit at either of the said ontlets whether the said dampers
are raised by means of a rod protruding through the horizontal hot plate (or hob) of
the range or a spindle protruding through the vertical front plate thereof and further
that by the addition of an opening at the top of the vertical portion of the forked
flue corresponding to that at the bottom and the union of a flap (to the descending
flue before named) which is made to revolve upon the said spindle the heat which
proceeds from the top of the fire across the oven top may be compelled to encircle the

page_text: oven until it finds exit at the lower aperture beneath the oven as shewn by the arrows
in the illustrations herewith. When the said flap is reversed and raised erect the
heat proceeds first down the descending flue chamber and encircles the whole outer
surface of the oven until it finds exit at the uppermost aperture in the vertical flue
pipe. The upper aperture may serve as an occasional and extraordinary smoke
escapement (when required) by fixing the before named flap loosely upon the spindle
so that the flap and spindle may he revolved independently of each other, and when
the said uppermost aperture is open the flap may be turned down over the descending
Alue and the smoke allowed to proceel direct from the fire to the said aperture.
Instead of the vertical portion of the forked flue being always behind the oven and
the back boiler it may sometimes be put with advantage between the oven and the
back boiler or on that side of the oven which is farthest from the fire.
In order to afford an escapement for the fumes and vapours arising from vessels
placed upon the fire and hob of the range 1 make the swinging shutter above the
pivotted flue pipe capable of adjustment in any required position so that it may
occasionally serve the purpose of a ventilator. I also furnish it sometimes with a
"hit and miss" grating for the same purpose and at other times I place a similar
grated flap within the back plate work, or chimney, of the range so that the said
grated flap may be easily removed and replaced for purposes of flue cleaning, the
grating being used as a ventilator for the range.
My third named object is but an enlargement of my last named one.
In some cases where I find it inconvenient to apply the last named provisions for
regulating and controlling the course pursued by the currents of heat proceeding
from the fire to each oven (or boiler) 1 employ double dampers of a somewhat
different construction and placed in other parts of the same flues or in the main
(central) flue of the range, thus when for convenience I effect this damping control
in the main central flu of the range, 1 construct therein one or more sets of twin
pivotted dampers each pair of dampers having only one spindle and each damper
having an independent action thereon. Each pair of pivotted dampers when confined
in a narrow flue space assumes a more or less V form, the spindle thereof being
located at the point of their union with each other-when two pairs are employed
they unite in the form (more or less) of a W the two lowest points thereof represent
the locality occupied by each spindle. On the right and left of each spindle the flue
space is formed into separate chambers by such means as a midteather or division
plate which gives to each pair of such pivotted dampers a form resembling Y and (in
the case referred to) of two contiguous ones thus Y, Y. These figures fairly serve to
illustrate certain attitudes of my twin pivotted dainpers.
It will readily be understood that the two (or four) leaves of these damper sets
may be made to close it completely and as each or any one of them is revolved upon
its spindle one or other of the flues associated therewith will be opened or closed
thereby. I have so constructed these dampers that any one only of their constituent
flaps may be folded completely over until it lies against its mate or each flap may
be revolved within one half only of its orbit and is then in contact with its mate.
By means of such a complete damping mechanism as that just detailed it will be
seen that I can regulate the currents of heat which flow through any or all of the
flues of my cooking range in any manner required.
Iu fig. 1 I have shewn an upright metal flue box, A, fitted behind a metal plate B
and shewn resting upon the hob ((()) of a cooking Range. In the lower part of
the plate B is an aperture which is bordered on the right, left & top sides with a
projecting flange D. This member (I)) is furnished with various slots, E and E³, for
the purpose of pivotting therein the flue pipe as shewn in figs. 6. 5. 4. 3 & 2. To
the upper part of the flange D is pivotted a swinging shutter (or ventilator) F, either
grated as shewn in fig. 2 or solid as shewn in fig. 3. The Box A is provided with
sloping or curved ledges, G, for the purpose of guiding in an upward direction the
loose bob plate, H, when the fire cover J, to which the plate H is hinged, is pushed
back from the fire. In figures 2 and 4 the convertible flue arrangement is shewn
turned up into the flue Box A, for close fire purposes, and in figures 3 and 5 it is.

page_text: represented as turned down upon the pivots E³, until its open end, K, is in line with
the back of the fire space L. By means of a projection or knob, E. figures 23 and 6
the pivotted flue pipe K may be raised up into the position shown in figures 2 and 4
or lowered into those shewn in figuros 3 and 5 the swing flap, or shutter, F, yielding
backwards or forward as the flue pipe is pushed into its recess or withdrawn from
it. The "hit & miss" grating shown in the flap F fig. 2 is for purposes of ventilation.
If it is not required to push back the hob plate, H, into the back flue
spaco,
Box A (or curved rails if employed instoad of it may be dispensed with. This part of
my apparatus is derived from the patent No. 13,194 dntod Nov. 2nd 1885).
Similar letters and marks of reference are employed in figs. 1 to 6 inclusive to
to indicate corresponding parts.
the
In figs. 7 to 17 I have shown a variety of diagrams illustrative of my forkel flue
arrangement for heating cooking range ovens. Fig. 7 is an external view looking
upon the back of an oven A which is furnished with a forked flua, B, & Figs. 9 and 10
are views of the interior of the forked flue shewing its three principal apertures (). D
and E. In the vertical part of the flue B, fig. 10, 1 have shewn a twin dampor
formed of two rectangular belts (or tubes) F, Funited by one or more bars G and
raised, lowered and retained at any required height by means of a handle IL. When
the twin damper F, F, is raised up as shown in Figs. 10 and 11 (which are back and
front views) the forked flue is closed at J and opened at D and when F, F, is lowered
as shown in fig. 12 the flue is open at J and closed at D. In fig. 13 I have shown by
means of arrows the course which the heat takes from the fire spaco K around the
oven A until entering the back flue at D figs. 11 and 18 it finds exit at C-and in
fig. 141 bave shown. similarly, the manner in which the heat circulates around tho
oven and through the fluos as depicted in fig. 12.
The tubular or bolt shaped twin damper FF may consist as shown, of two belts
placed inside a tubular flue, B (fig. 7), and joined together by a bar G, or may consist
of one tube only of suitable length, or its equivalent. In fig. 11 it will be seen how
this tubular construction of the damper F allows the heat which enters the flue Bat 1)
to pass upward until it finds exit at Cinto the other flues of the range and in fig. 12
how the belt, collar or tube F closes the aperture D, and opens that marked J, thereby
allowing the current of heat to enter the diagonal part of the flue Bat. E and
find exit from J to C. By providing slots or grooves in the arm, or handle H,
figures 7 to 15 the tubular damper F, F, may be fixed and retained at any required
height.
Instead of raising and lowering the tubular damper F by means of an arm, or
handle, H, protruding upwards through the hob of the range 1 sometimes raiso and
lower it by means of a spindle fitted horizontally beneath the hob and protruding in
a forward direction through the front plate of the range, in a manner which is
commonly adopted with oven dampers for close fire ranges.
Figs. 8 and 15 represent my forked oven flue adapted for construction or
enclosure within a fiue chamber which covers one whole side of an oven ordinarily
the back side.
It may also be formed outside of either the right or left sides of an oven and upon
either the side that is nearest to the fire or that which is furthest away from it.
I consider it an advantage to form the flue B as an internal division within a fluo
chamber covering the whole of one side of an oven instead of making it a pipo shaped
flue (of any internal section) as an outside attachment projecting from the outside
wall of the oven as shown in Fig. 7. In figure 15 the space M is open to the under
side of oven and allows the heat to pass up into the space marked N where it remains
stagnant but of considerable service in heating the oven altho' it cannot pass from
thence into the flue B. In a similar manner the heat which enters that part of the
chamber which is marked P in the same illustration cannot circulate through the
flue B when the damper F closes the diagonal part at J as shewn in fig. 15.
I sometimes make the division plates B and B (figs. 10 and 15) loose and romove-
able through an aperture provided conveniently upon or near the hob so that the
spaces N and P may be easily cleaned out with a fluo brush.

page_text: In figure 17 I have shown a metal flap Q fitted upon the damper spindle R which flap
(rigidly fastened to the spindle) is frequently employed by cooking Range makers in
conjunction with the fire cheek Q and the flue space formed between the plate Q" and
the side of oven marked Q. When the flap Q is in the position shewn in this
illustration the heat cannot obtain access directly from the fire to the oven top but is
compelled to circulate down that side of the oven which is nearest to the fire and then
underneath it when it enters the flue B at the aperture marked E. If the flap is
turned down (by such means as the handle S2) until it rests upon the plate Q³, tlie heat
proceeds direct from the fire to the top of the oven, thence down the remotest side
thereof and into the fluo B.
As a substitute for the handle H, figs. 7 to 15, I sometimes employ the spindle
marked R and its handle S for the purpose of operating the dampers F in the flue B.
These tubular shutters are easily raised and lowered in the vertical part of the
flue B by a slotted crank R³ fitted upon the spindle R² as shown in fig. 16, or by any
other equivalent mechanism.
In figs. 16, 17 and 18 have shown a hit and miss sliding shutter beneath the hob,
which is marked T, for occasional use as a direct smoke escapement and for other fluo
purposes. In fig. 17 I have shewn this grated slide open and have indicated by arrows,
that a current of heat may be allowed to find passage through it at the same time that
the diagonal flue is open at J and the heat is entering into it at E; so that whilst the
fiercest heat from the fire proceeds, first, directly to the bottom of the oven it is not
wholly cut off from the top and the furthest side of it. By means of the bolt-like
arm and the pin T³, or their equivalents, this sliding grate may be easily opened
and closed. A further purpose for which I have devised this sliding grate is to afford
a direct escapement for the smoke into the principal flue of the range whenever the
fire is first lighted, subsequently mended, or gives off its smoke through the crevices of
the cover plates upon the hob. When this grate is opened and the flap Q turned down
upon the plate the flame or smoke, from top of fire, proceeds directly through
it to the main flue until it is considered desirable to close the grating. By fitting
the flap Q loosely upon the spindle R, instead of making it fast thereto, I am
onabled to operate the said flap in any way required independently of the spindle R
and the (single or twin) tubular damper F in the fino B.
In figures 19 and 20 I have shewn another way of controlling the direction in
which the heat is made to circulate around an oven by means of the (single or twin)
tubular damper, F, confined in a vertical fluo, B, and operated by means of a
spindle, R, united moveably or immoveably to a flap, Q, and a slotted arm, R², so
that when the flap, Q, is turned upright as shewn in fig. 19 the aperture, D, is closed
by the damper, F, and the heat encircles the whole of the oven as shewn by the
arrows until it finds exit at the aperture C: if the flap is then folded down upon the
plate as shown in fig. 20 the damper, F, closes the aperture (and opens that at D
when the heat proceeds across the top of oven down the far side, underneath it and
enters the flue B at the aperture D.
In figure 21 I have shewn my forked flue B in an inverted position and damped by
means of a single sliding plate instead of a (single or twin) tubular shutter. On one
side of the oven A, (ordinarily at the back of it), I provide a flue chamber as before
described and make a flue opening thereto marked D2 figure 21. I also employ the
the flap Q (attached immoveably to the spindle R) in this arrangement and when the
flap is turned down upon the plate Q as shewn in this figure the heat proceeds over
the oven top, down the far side and underneath it to the opening D (as shewn by
the arrows) and on entering the back flue chamber it is diverted by the diagonal
plate B³ across the back of the oven and finds exit at a limited flue aperture at the
part marked C. If the spindle R and flap Q are reversed as shewn in fig. 22-the
heat proceeds to the underside of oven, as shewn there by the arrows, and finds exit
into the back flue B at the opening C; the turning of the spindle having moved the
sliding damper plate C from over the aperture C³ until it covers that marked C+
and thus affords an outlet for the heat at (3, and that which occupies the back
flue chamber remains as stagnant atmosphere of hot air.

page_text: 251 have shown a similar arrangement of nue apertures and
damping appliances to that just described in connection with fig. 21 with the exception
of the diagonal plato B.
It must ho understood that the fino space C figs. 21, 22 & 23 is open only to the
top of oven as shewn, except when the plate, C, is removed, as shown in figs. 21
and 22. The opening D figs. 22 and 23 may be made to open either into a
capacious hot air chamber, or flue, covering the principal part of the oven back with
an opening at (or into a confined vertical flue B as shown with dotted lines :—the
space Clins no opening (except at (9) into any part of the back flue B.
In figures 24 to 29 I have shown the mechanism with which I control the currents
of heat proceeding through a (two or) three-way fluo connected with a stove or cooking
range. In fig. 24 (which shows a two way fine) the pair of dampers A and B partake
the form of the letter V and when coupled with a division plate Cresemble the
letter Y each flap covers a flue marked 1) and E respectively--(the front plate being
removed and the interior of the main flue being shewn here) both of which are closed.
In fig. 25 a three-way Hue is shown controlled by two sets of dampers which partake
the form of the letter W in their closed relations--and when associated with the
plates 0-0 appear like a double Y.
In figure 26 all these flaps, A and B, and their associate flues are shown open-in
fig. 27 the centre flue is open and the side ones closed-whilst in Fig. 28 only one
side flue is open. Fig. 29 shows the positions of the handles F, when all the flues
are closed this view represents the main flue covered by the cove plate, or panel, G.
Figs. 30 to 38 shew the damper flaps, A and B, detached from each other and their
spindle, and from them it will be seen that the two flaps are united upon one spinule
6g. 82 after the manner of a hinge and by means of two separate handles, F, either
leaf, A or B, may be turned one way or the other independently of its companion.
The door marked H' Figs. 1 and 2 is a removeable one and through it any
number of such associate "Hues may be cleaned. It may also be fitted with n
ventilating grate as shewn in Fig. 1.
I am aware that loose, flue cleaning doors, such as those marked H³ in
figures 1. 2 and 29 are commonly used in connection with cooking ranges, also that
cooking range ovens have been frequently made with a diagonal Hue, traversing the
outside back plates thereof, and thint single and double damper flaps, resembling that
marked in tho accompanying illustrations, attached rigidly to one spindle, have
been employed on the top part only of a cooking range oven; further that a combined
open and close fire flue box, composed of two loose and associate halves, fitted together
and sliding, one upon the other (one portion thereof being hinged to the fire cover)
and when not required as an open fire flue, can he turned up into a recoss at tho
back of the range, (but not into the back flue itself) it will therefore be understood
that do not claim, broadly, as my invention, such appliances as grated or plain
cleaning doors, spindle flaps such as Q or a pivotted flue for combined open & close
fire purposes except of the specific or essential character and in the combinations
horein described and shown.
The fluo damping provisions herein described in connection with the oven and
boiler flues of a stove or cooking range are equally applicable to a stove or
heating apparatus which is not designed or used for cooking purposes and it will
therefore be understood that the pivotted and other double fluo damping mechanism
herein described are intended for combination with apparatuses for heating churches
and other large structures, and for general trade purposes whore a two, three or four
way fluo requires to be controlled in such manner as horein particularised.
Having now particularly described and ascortained the nature of my said inven-
tion and in what manner the same is to be performed 1 declare that what I
claim is-
1st. In a stove or cooking range the combination therewith of a pivotted flue
pine (figs. 2 to 6) all substantially as herein described and shown and for nurnoses

page_text: 2nd. In a cooking range the combination with either oven thereof of a forked flue,
all substantially as herein described and shewn and for purposes specified.
3rd. In a stove or cooking range the combination therewith of (single or) twin
tubular dampers all substantially as herein described and shewn and for purposes
specified.
4th. In a cooking range the combination therewith of the dampers Q and F united
with a spindle Rall substantially as herein described and shewn and for purposes
specified.
5th. In a cooking range the combination with either oven thereof of the flue
passages and damping mechanism therefor as shewn in figures 19 and 20 all substantially
as herein described and for the purposes specified.
6th. In a cooking range the combination with either oven thereof of the flue
passages and damping mechanism therefor shewn in figure 21 all substantially as
herein described and for purposes specified.
7th. In a cooking range the combination with either oven thereof of the flue
passages and damping mechanism therefor shewn in figures 22 & 23 all substantially
as herein described and for the purposes specified.
8th. In a stove or cooking range the combination with any of the flues thereof of
(one or more sets of) twin dampers pivotted upon one spindle as shewn in figures 24
to 28 all substantially as herein described and for purposes specified.
9th. In a stove or cooking range the combined open and close fire flue, and flue
damping mechanism, all substantially as herein described & shewn and for purposes
specified.
10th. In a Cooking Range the combination therewith of the open and Close fire
mechanism, with either solid or grated shutter F (figures 2 and 3) all substantially as
berein described and shewn and for purposes specified.
Hated this Second dev
Hated this Second day o
JOSEPH LOCKWOOD,
Argyle Street, Glasgow, Agent for M. Cockburn.
JOSEPH
LOCKWOOD,
Argyle Street, Glasgow, Agent for M. Cockburn.