Improvements in the Method of and Apparatus for Electrically Heating or Working Metal or other Materials capable of Momentarily Withstanding the Heat of an Electric Arc.
Year: 1893

page_text: Date of Application, 10th Oct., 1893-Accepted, 16th Dec., 1893
COMPLETE SPECIFICATION.
Improvements in the Method of and Apparatus for Electrically
Heating or Working Metal or other Materials capable of
Momentarily Withstanding the Heat of an Electric Arc.
A communication by CHARLES LEWIS COFFIN, of 980, Jefferson Avenue, Detroit,
in the County of Wayne and State of Michigan, United States of America,
Chemist.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for
Foreign Patent Solicitors, 6 Lord Street, Liverpool, and 6 Bank Street,
Manchester, both in the County of Lancaster, and 323 High Holborn, in the
County of Middlesex, Civil Engineer, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
This invention consists in a method of and apparatus for electrically heating
metal or working metal, hereinafter fully described and claimed.
Figure 1 is a side clevation with the lower end of the carbon partly in section.
Figures 2 and 3 are diagrammatic views showing the magnet located beneath the
material, the lower end of the carbon being broken away in Figure 2.
Figure 4 is a side elevation of the modified apparatus.
Figure 5 is a side view of Figure 6: and
Figure 6 is an end view of a modified apparatus somewhat like that shown in
Figure 4.
In Figure 1, T represents a supporting table, and M represents a metal plate
to be heated or worked, lying on said table. D represents a goose-neck or support
to carry the carbon and working mechanism above the material to be heated.
represents a collar on the end of goose-neck D, to fit the metallic core E of an
electro-maguet A, said core E being feathered or splined into collar F, as shown
by the spline f, to prevent its rotation, and being supported at any desired position
by a set screw K passing through collar F. L represents a collar fitted slide on
core E and having an upward extension R, provided with teeth; and a collar N
provided with a set screw to grasp the carbon C which lies within the core E.
S represents a toothed segment pivotted in the bracket P carried on goose-neck D,
and provided with a lever O, by means of which the collar N and with it the
carbon C may be raised or lowered at will. J represents a loose iron collar
encircling core E, and adapted to rotate thercon, the surface of which is, either as
a whole, adapted to receive a belt, or may be provided with a groove B for that
purpose. G represents an iron collar clamped in collar J by a set screw, and
having a projecting arm to which is connected an arm H of magnetic material,
which is preferably made adjustable, as shown in Figure 1, the arm H, therefore,
forming one pole of the core E of the electro-magnet A, and this pole may be
brought in close proximity to the lower end of carbon C.
In the arrangement shown in Figure 1, material M is connected with one
terminal of an electric generator by a conductor a, and the carbon C is connected
with the other terminal of said generator by a conductor y. y', y³, represent
conductors by which the bobbin of electro-magnet A is connected with the terminals
of a generator of electricity either directly or in shunt circuit with conductors a
and y.
The operation of this device is as follows:-
The parts being in the position shown in Figure 1, an electric current being
passed through conductors and y, material M and carbon C, by lowering the
M and than mising it a voltaic arc will be

page_text: formed between said carbon and the material, as indicated in the figure. A current
also passing through electro-magnet A magnetises the core E H. Now by rotating
the collar J and with it the arm H of the core, said arm travels round and round
said carbon C, and according to its polarity either attracts or repels the voltaic arc,
which travels round and round either following or receding from arm H, thus
causing said arc to affect a much larger portion of the material M than is due
simply to its normal size.
In Figures 2 and 3, the arrangement of parts in Figure 1 is modified by putting
the electro-magnet A beneath the material M, in which position it will attract or
repel the arc and cause it to follow pole H of said electro-magnet when said pole is
rotated.
In the diagram of Figure 4, the carbon C, instead of being a rod, is a plate con-
pected by conductor y with one terminal of a generator of electricity, the material M
being connected by the conductor with the other terminal. In this modification,
the pole H of maguet A does not rotate, but the magnet is reciprocated along a
way W by being mounted on a carriage V fitted to traverse said way and recipro-
cated thereon by means of a crank Q and pitman U.
In Figures 5 and 6, two carbons C and C' are used, insulated from each other
by insulation, (the carbon C¹ being elongated a little in Figure 5 to make it visible)
and the magnet A with its pole H is reciprocated in the same manner and by the
same mechanism as that above described for Figure 4. In Figures 5 and 6,
however, the material M is not in circuit, the arc being sprung between the two
conductors C and C₁, which are connected with the terminals of a generator by
means of the conductors x and y.
It is found that, by this method, the efficiency of a voltaic arc may be greatly
increased as applied to practical work, for it is not permitted to concentrate its heat
upon one point, but it is rapidly moved from one point to another, whereby an arc
of greater power may be used than if it is stationary, and a correspondingly greater
effect produced. This apparatus and method is applicable for heating plates of
other material in which it is desired to produce incipient fusion such as glassy
fictile or other silicaceous or boraceous compounds.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is :-
1. In an apparatus for electric heating and metal working, the combination, with
the material, an electrode, means for maintaining a voltaic are between said material
and electrode, of a movable magnetic pole and means for giving motion to the same,
substantially as shown and described.
2. In an apparatus for electrically heating netal, the combination of a
support for the material to be heated, a support for an electrode, means for main-
taining a voltaic arc in proximity to said material, an electro-magnet having its
pole in proximity to said voltaic arc, and means for moving said magnetic pole,
substantially as and for the purposes set forth.
3. In an apparatus for electrically heating metal, the combination of mechanism
for producing a voltaic arc, an electro-magnet carried on a movable support in
proximity to said arc, and means for moving said magnet, substantially as and for
the purposes set forth.
4. The combination in an apparatus for heating and working metals or other
materials by an electric arc, of electrodes for the formation of said arc, and an arc
disturber consisting of a field of magnetic force, and means for shifting the action
or direction of such field during the progress of the work.
5. The combination, in an apparatus for heating and working metals or other
materials by an electric arc, of electrodes for the formation of such arc, and an arc
disturber consisting of a field of magnetic force and a mechanism for shifting the
magnetic field into regularly varying positions with respect to the electric arc.
6. The combination, in an apparatus for heating or working metals or other

page_text: materials by an electric arc, of electrodes for the formation of the arc and a rotating
magnetic field acting as an are disturber for the arc formed between the electrodes.
7. In an apparatus for electrically heating metal, the combination of mechanism
for producing a voltaic arc, a magnet carried on a movable support in proximity to
said arc, and meaus for moving said magnet, substantially as and for the purposes
set forth.
8. The improved method of electrically heating or working metal substantially as
described, whereby the arc is prevented from concentrating its heat upon one point
but is rapidly moved from one point to another.
Dated this 9th day of October 1893.
WM. P. THOMPSON & Co.,
Agents for the Applicant.