IMPROVEMENTS IN FURNACES FOR MELTING METALS AND METALLIC ALLOYS, AND FOR OTHER HEATING PURPOSES
Year: 1880

page_text: LETTERS PATENT to Charles Carr, the younger, of Smethwick, in the County
of Stafford, Brassfounder, for an Invention of "IMPROVEMENTS IN FURNACES
FOR MELTING METALS AND METALLIC ALLOYS, AND FOR OTHER HEATING
PURPOSES."
PROVISIONAL SPECIFICATION loft by the said Charles Carr at the Offico
of the Commissioners of Patents on the 19th June 1880.
CHARLES CARR, the younger, of Smethwick, in the County of Stafford,
Brassfounder. "IMPROVEMENTS IN FURNACES FOR MELTING METALS AND
METALLIC ALLOYS, AND FOR OTHER HEATING PURPOSES."
My Invention consists of the improvements hereinafter described in furnaces,
which improvements are especially applicable to furnaces for melting metals and
metallic alloys, such, for example, as copper, brass, and iron, but may also be applied
to furnaces for other heating purposes.
I make the outer casing of the furnace of plates of cast iron bolted together, the
two plates constituting the sides of the furnace having each two legs and feet, by
which the body of the furnace is supported at a convenient distance from the
ground.
The supports at the front and back of the furnace for the fire bars are fixed in
holes at the tops of the legs, and when the said supports and the front and back
plates of the furnace are put in their places the whole are bound together by screw
bolts passing through the side plates of the furnace.
At the bottom of the side and front and back plates small projections or brackets
are cast, and on these a frame rests, upon which frame the brick work lining of the
furnace is supported. The brickwork lining may either be situated close against
or at short distance from the cast iron casing of the furnace. For a casting or
metallurgical furnace I prefer to build the brick work lining at a short distanco from
the cast iron casing. A current of air ascends between the casing and lining of the
furnace, which current of air keeps the casing cool.
When the brickwork is at a short distance from the casing I prefer to fix plates
of cast iron within and at a short distance from the casing. Against these plates
the brickwork is built. The said plates support the brick work, and maintain it in
working order longer than when unsupported.

page_text: Instead of using ordinary fire bars for supporting the fuel I sometimes employ a
continuous cast iron plate to form the bottom of the furnace and to support the
fuel.
In this case, air for supporting combustion is supplied through horizontal slots in
the sides of the casing and lining. By this arrangement a steady combustion may
be maintained for a long period, the plate forming the bottom of the furnace only
requiring to be moved at long intervals for the clearing away of the ash collected
upon it.
Or the slots in the sides of the furnace may be used in combination with fire bars
at the bottom of the furnace. In this case, a layer of coke on the fire bars (which
layer does not ignite below the level of the slots, or ignites but very slowly below
that level) supports the burning fuel above, and practically prevents access of air
through the bottom of the furnace. By putting the fire bars close together they
form practically a continuous plato.
Furnaces constructed according to my Invention are portable.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Charles Carr in. the Great Seal Patent Office on the 11th December
1880.
CHARLES CARR, the younger, of Smethwick, in the County of Stafford,
Brassfounder. "IMPROVEMENTS IN FURNACES FOR MELTING METALS AND
METALLIC ALLOYS, AND FOR OTHER HEATING PURPOSES."
My Invention consists of the improvements herein after described in furnaces,
which improvements are especially applicable to furnaces for melting metals and
metallic alloys, such, for example, as copper, brass, and iron, but inay also be applied
to furnaces for other heating purposes.
I make the outer casing of the furnace of plates of cast iron bolted together, the
two plates constituting the sides of the furnace having each two legs and feet, by
which the body of the furnace is supported at a convenient distance from the
ground.
The supports at the front and back of the furnace for the fire bars are fixed in
holes at the tops of the legs, and when the said supports and the front and back
plates of the furnace are put in their places all of them are bound together by screw
bolts passing through the side plates of the furnace.
At the bottom of the side and front and back plates small projections or brackets
are cast, and on theso a frame rests, upon which frame the brickwork lining of the
furnace is supported. The brickwork lining may either be situated close against or
at a short distance from the cast iron casing of the furnace.
For a casting or metallurgical furnace I prefer to build the brickwork lining at a
short distance from the cast iron casing, and I fill the space between the brickwork
and casing with a mixture of sand and fire clay or other imperfect conductor of
heat. The casing is thereby kept cool.
Instead of using ordinary fire bars for supporting the fuel I sometimes employ a
continuous cast iron plate to form the bottom of the furnace and to support the
fuel. In this case, air for supporting combustion is supplied through horizontal
slots in the sides of the casing and lining. By this arrangement a steady
combustion may be maintained for a long period, the plate formning the bottom of
the furnace only requiring to be removed at long intervals for the clearing away of
the ash collected upon it.
Or the slots in the sides of the furnace may be used in combination with fire
bars at the bottom of the furnace. In this case, a layer of coke on the fire bars
(which layer does not ignite below the level of the slots, or ignites but very slowly
below that level) supports the burning fuel above, and practically prevents access
of air through the bottom of the furnace. By putting the firebars close together
they form practically a continuous plate.
Furnaces constructed according to my Invention are portable.
I will now proceed to describe with reference to the accompanying Drawing the
manner in which my Invention may be performed.
Figure 1 represents in front elevation, Figure 2 in side elevation, and Figure 3
in vertical section a furnace constructed according to my Invention; Figure 4
reprosents in section a modification of the same, and Figure 5 is a perspective view
of the furnace, Figure 4.
The same letters of reference indicate the same parts in the several Figures of
the Drawing.
The side plates forming the casing of the furnace are marked a, a, and the front
plate is marked b. The back plate, not represented in the Drawing, is similar to
the front plate b, excepting that it has tho exit flue c made in its upper part.
Each of the side plates a has two legs and feet a³, a², made in one piece with it,
for supporting the furnace at a conveniont height from the ground. The supports
or bearers at the front and back of the furnace for the fire bars d are marked c, the
said supports or bearers e being fixed in holes at ƒ in the tops of the legs a³, a².

page_text: The said supports e, e, side plates a, a, and front and back plates, are bound together
by the screwed rods and nuts at g, g, passing through the side plates of the furnace;
h, h, are projections or brackets cast at the lower part and on the inner sides of the
sido plates a, a. On these brackets h, h, the cast iron frame i rests, and on this
frame the brickwork lining k of the furnace is supported.
The brickwork lining may be in contact with the inside of the side plates a, a,
and front and back plates, but I prefer to leave a space between them, as
represented at 7, Figure 3, which space I fill with a mixture of sand and fire clay or
other imperfect conductor of heat. By this means the metal casing of the furnace
is kept cool.
The bearers or supports c, e, for the firo bars are situated below the level of the
bottom of the furnace, air for supporting combustion consequently enters all round
the furnace, at bottom as well as between the fire bars. The combustion is thereby
made more vigorous round the sides of the crucible or melting pot than under its
bottom, and the sinking of the crucible in the furnace is thereby to a great oxtent 1
prevented.
When I employ a continuous plate for the bottom of the furnace, or a series of
bars arranged close or nearly close together, I construct and arrange the parts in
the manner represented in Figures 4 and 5, that is to say, I form in each of the
side and back and front plates a slot m, and a corresponding slot in the brickwork 2
lining at n. Air for supporting combustion enters at the slots m, n.
By this arrangement a steady combustion may be maintained in the furnace for
a long period, the continuous or nearly continuous bottom of the furnace only
requiring to be removed at long intervals for clearing away the ash. Combustion
takes place only to a limited extont below the level of the slots m, n, and the 2
crucible or melting pot does not sink, or does not sink so much, in the furnace as in
ordinary furnaces.
Having now described the nature of my Invention, and the manner in which the
same is to be performed, I wish it to be understood that I claim as ny Invention
of "Improvements in Furnaces for Melting Metals and Metallic Alloys, and for 3
other Heating Purposes,"
First. The general arrangement of the metal casing of the furnace, herein before
described and illustrated in the accompanying Drawing, that is to say, the side
plates with their legs, and feet, and internal brackets, the front and back plates, and
bearers for the fire bars, bound together by screwed rods and nuts, whether the 3
front, back, and side plates have horizontal slots for admitting air or are without
the said slots.
Secondly. Supporting the brickwork lining of the furnace on a cast iron frame
carried by the brackets on the side plates, as herein before described and illustrated
in the accompanying Drawing.
Thirdly. Fixing the bearers or supports for the fire bars at such a level that
air for supporting combustion shall enter all round, at the bottom of the furnace
as well as between the fire bars, as herein described and illustrated in the
accompanying Drawing.
In witness whereof, I, the said Charles Carr, have hereunto set my hand 4
and seal, this Tenth day of December, in the year of our Lord One thousand
Witness,
RICHARD SKERRETT,
37, Temple Street,
Birmingham.
CHARLES CARR, JUN³. (L.S.)