Improvements in and connected with Electric Furnaces for the Production of Calcium Carbide and other Substances.
Year: 1897

page_text: Date of Application, 23rd Nov.,
4007
Complete Specification Left, 23rd Sept., 1898-Accepted, 23rd Nov., 1898
Complete Specification Left, 23rd Sept., 1898-Accepted, 23rd Nov., 1898
PROVISIONAL SPECIFICATION.
Improvements in and connected with Electric Furnaces for the
Production of Calcium Carbide and other Substances.
I, HERBERT SIDNEY RIANT, of 36, Ockenden Road, Southgate Road,
London, Gentleman, do hereby declare the nature of this invention to be as
follows:-
:-
The objection of this invention is to prevent waste of heat in electric furnaces and
to facilitate the introduction of the material to be treated into the furnace and
within the influence of the electric arc between the electrodes in the furnace.
In electric furnaces as at present constructed the heat generated between the
electrodes is sufficiently intense to fuse the materials under treatment when they
are directly within the influence of the eléctric are but at a distance of two inches
or thereabouts from the arc the heat is insufficient for fusion and calcium carbide or
other substances prepared in such furnaces are not chemically pure.
Furthermore a great deal of the heat generated in the are is dissipated uselessly by
reason of the furnace being partly constructed of conducting materials which attract
the current and tend to increase the width of the arc thereby reducing the tempera-
ture of the arc.
My present invention is designed to keep the arc within a small a space as
possible and to feed the materials under treatment into the furnace in such a
manner that they may pass through the most intense point of the arc.
Now according to this invention I provide a suitable furnace of non-conducting
refractory materials such as ganister for instance and I close the top of the furnace
with a suitable cover.
The said cover is provided with a suitable stuffing box through which passes a
conductor to the lower end of which is attached the carbon electrode. This elec-
trode is capable of being raised and lowered and inclined to any suitable angle.
The hearth of the furnace is formed of an inclined carbon block or slab which
acts also as the other electrode.
The materials to be fused are fed into the furnace and delivered between the
electrodes by means of an inclined shoot formed of non-conducting refractory
material.
I provide also a suitable regulating device at the top of the inclined shoot to
enable predetermined quantities of material to be fed into the arc at intervals.
The regulating device may take the form of a rotating cylinder, having slots or
perforations therein.
The fused material runs off the hearth into a suitable mould preferably so
shaped as to form the finished product into sticks.
I provide also a pipe entering the furnace at the top and provided with flaring
mouths by means of which any gas generated may be drawn off and delivered into
a suitable receiver in which the material to be treated may be dried or heated be-
fore being passed into the furnace or the gases may be condensed or washed or
otherwise treated.

page_text: The mould may be operated and emptied by mechanical means.
The lower electrode is so formed that the materials treated cannot clog thereon
and cause short circuiting.
Dated 22nd November 1897
H. C. FOWLER,
11, Furnival Street, Holborn, London, Agent for Applicant.
Improvements in and connected with Electric Furnaces for the
Production of Calcium Carbide and other Substances.
I, HERBERT SIDNEY RIANT, of 36, Ockenden Road, Southgate Road, in
the County of London, Gentleman, 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 electric furnaces for the production of calcium carbide
and other substances.
In electric furnaces as generally constructed at the present time the heat
generated between the electrodes is sufficiently intense to fuse the materials under
treatment when they are directly within the influence of the electric arc, but at a
distance of two inches or thereabouts from the arc the heat is insufficient for fusion
and the calcium carbide or other substances prepared in such furnace is therefore
not chemically pure. Furthermore a great deal of the heat generated in the are
is dissipated uselessly by reason of the furnace being partly constructed of con-
ducting materials which attract the electric current and tend to increase the width
of the arc and thereby reduce the temperature.
The object of this invention is to confine the electric arc within as small a space
as possible and to feed the materials to be treated into the furnace in such a manner
that practically the whole of them pass through the most intense point of the arc,
so that the resulting product is chemically pure.
In order that my invention may be clearly understood and readily carried into
effect I will now proceed to describe the same more fully with reference to the
accompanying drawings in which:
Figure 1 is a sectional elevation of a furnace constructed according to my inven-
tion, and
Figure 2 is a side elevation of the mechanism for adjusting the position of the
movable electrode in the said furnace.
A A are brickwork pillars supporting the furnace and a is non conducting
refractory material, such as ganister, lining the furnace. B is a conical, preferably
cast iron, cover, which rests on a top plate 63 and serves to close the top of the
furnace and collect waste gases. This cover is provided with an outlet 6 for the
escape of waste gases which may be led through a pipe into a receiver and em-
ployed for drying the materials to be treated in the furnace; or the said gases may
be condensed or washed or otherwise treated. At the crown of the cover Ban
opening or socket 62 is formed, into which fits a ball C so as to form a universal
joint herewith. This ball has a central passage c therethrough which is provided
with a suitable stuffing box c¹ and through which a copper rod D passes. The
lower end of this rod D carries the upper carbon holder d, and its upper end has
secured to it a screwed sleeve d¹. Mounted on the sleeve d' is a screw nut d
having teeth on its outer periphery so as to form a worm wheel. E is the
upper adjustable carbon electrode, and E¹ is a fixed inclined carbon block or slab
forming the hearth of the furnace and constituting the lower electrode.

page_text: Referring to Figure 2 F is a bar which has a rack f formed upon it. f¹, f are
brackets fixed to a beam or otherwise conveniently supported and provided respect-
ively with the slots N,, N¹ through which the bar F passes so as to be capable of
sliding therein. These slots N, N1 are of greater depth than the bar I so that the
latter is capable of a certain amount of vertical movement when the upper electrode
is laterally adjusted as hereinafter described. G is a rotary horizontal tube or
sleeve one end of which is carried in a slot Nº in the bracket f and the other end
of which is supported from the rod F by the bracket f³. The slot N is of sufficient
depth to allow the sleeve G to move vertically therein for a short distance, and the
bar F is capable of sliding longitudinally in the bracket f³. This tube or sleeve G
is provided with a worm g and a hand wheel g¹. H is a worm wheel which is
journalled in suitable bearings in a bracket secured to the bracket f³,
and which gears the worm g on the sleeve G with the rack f, on the bar F. J is
a rod which passes through the sleeve G and is provided at one extremity with the
hand wheel and has its other extremity supported by a bracket f³ secured to the
bar F. is a worm secured to the rod J and engaging with the worm wheel on
the nut. K is a hopper for containing the material to be treated. k is an
inclined shoot provided with a removable spout for delivering the material to
be treated from the hopper K into the furnace between the electrodes. is a
perforated rotary cylinder situated at the top of the shoot k, the perforations in
which operate in conjunction with perforations in a fixed outer cylindrical casing
for regulating the feed of predetermined quantities of the material to be treated,
into the furnace at intervals. is a hand wheel for rotating the cylinder 1.
al is the foundation plate of the furnace and is preferably of cast iron. L L are
wrought iron cross bearers encastened into the pillars A A. and supporting joists 1,
carrying brackets 1. These brackets 1 support rollers 12 on which rests the cast
iron mould M for receiving the finished product. e and el are the wires respectively
connecting the electrodes E, E¹ to the opposite poles of a suitable source of electricity.
When the furnace is required for use the electric circuit is completed and the
material to be treated is fed by means of the hopper K, cylinder 2, and shoot k into
the furnace; the said material being delivered by the spout directly into the
electric arc between the electrodes E and E¹, waste of heat being thus prevented.
Owing to the construction and arrangement of the lower electrode E' and also by
reason of the adjustability of the upper electrode E the material cannot clog
therein and cause short circuiting.
The material when fused runs off the hearth of the furnace, through the opening
therein, into the mould M which is preferably so shaped as to form the finished
product into sticks rods or bars. The mould is withdrawn from the furnace when
required.
:
In order to regulate the electrode E vertically, the hand wheel ; is rotated in
the required direction, rotary movement being thereby communicated through
the rod and worm to the nut the sleeve & and the rod D being
thereby raised or lowered as required. In order to regulate the electrode E
laterally it may be caused to move about the centre formed by the ball C and
socket 2, by means of rotating the hand wheel g¹ and thereby imparting angular
movement, through the medium of the worm a worm wheel H and rack f, to the
bar F, rod J and sleeve G, thus moving the rod D and electrode E angularly about
the aforesaid centre.
It will be seen that in the above described furnace the usual crucible containing
the material to be treated and forming one pole of the furnace is dispensed with and
the waste of current generally caused by heating such crucible above the level
of the material under treatment and the liability to short circuit by the molten
material is prevented, all the current possible will therefore be passed directly
through the material under treatment.
In this furnace the finished product falls by gravity, when sufficiently fused,
into the mould and is thus continuously drawn off without stopping the furnace,
and there is consequently no loss of current (as is generally the case with furnaces

page_text: or ordinary construction) in keeping a mass of finished product in a molten state
until it is periodically removed.
Owing to the fact that the total current in this furnace is concentrated at the
point where the material is treated, the finished product is delivered in a very pure
condition.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I claim
is:-
•
1. An electric furnace in which the substances to be treated are delivered onto
the lower electrode and directly into the electric arc, and from which the finished
product is continuously withdrawn without stopping the furnace, for the purpose
specified.
2. An electric furnace the hearth of which is formed by a fixed inclined electrode
onto which the substances to be treated are delivered and from which the finished
product falls by gravity, for the purpose specified.
3. In an electric furnace the combination of a fixed inclined electrode forming
the hearth of the furnace, and a perforated rotary cylinder for regulating the
delivery into the furnace of the substances to be treated, for the purpose specified.
4. In an electric furnace the combination of a fixed inclined electrode forming the
hearth of the furnace, and a vertically and laterally adjustable electrode, for the
purpose specified.
5. An electric furnace for the production of calcium carbide and other substances,
having its parts constructed, arranged, and operating substantially as herein before
described with reference to the accompanying drawings, for the purposes specified.
Dated this 23rd day of September 1898.
HASELTINE, LAKE, & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.