An Improved Method of and Apparatus for Heating, Welding, or Working Metals Electrically.
Year: 1893

page_text: Date of Application, 18th July, 1893-4ccepted, 2nd Sept., 1893
COMPLETE SPECIFICATION.
An Improved Method of and Apparatus for Heating, Welding, or
Working Metals Electrically.
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, Man.
chester, both in the County of Lancaster, and 323 High Holborn, in the County of
Middlesex, Civil Engineer, 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 consists in an improved method of and apparatus for heating,
welding or working metals electrically, hereinafter fully described and claimed.
Figure 1 is an elevation, partly in section, of a heating tool;
Figure 2 is a vertical section of the lower end of the tool, and
Figure 3 is a diagram showing the tool in position with two articles to be heated
and welded together.
For certain purposes, it is desirable, in applying to metal an arc sprung between
two extraneous conductors, to cause said arc to traverse a portion of the material,
and this can be done by causing the arc either to travel on the conductors between
which it is sprung magnetically or mechanically, the first being the subject of this
application.
In carrying out this invention, a hollow carbon A and a carbon rod B are
provided, the solid carbon B being secured within the hollow carbon A. by fastening,
to the hollow carbon A, a hollow metallic holder D, and to the solid carbon a
metallic holder E of such size as to slip within, or rest on, or otherwise engage with,
holder D, the two being insulated by insulation shown at I.
The space between the two carbous may be filled up with a refractory material F
if desired. To the holder D is attached an electro-magnet C which encircles the
hollow carbon A, and to the insulated ends of said electro-magnet C is attached a
handle T, provided with an insulation H. The holders E and D are connected and
thereby the carbons B and A with the terminals of a source of electric energy, by
means of the conductors y and x, which may for convenience pass through handle T
as shown in the drawing. The terminals of the bobbin of electro-magnet C are
connected with the conductors y and x by small conductors y' and ', as shown in
Figure 1. G represents a shield for the handle. If the carbons A and B are
connected by a conductor more fusible than the electrodes and a current is passed
through the conductors y and x, an arc will be formed between carbons A and B at
their extremities, as indicated in Figures 1 and 3, and at the same time the
electro-magnet will be energized, and the effect of said electro-magnet on the
arc is to cause it to rotate around the end of the carbon A, its motion being
more rapid as the magnetic intensity increases, so that, instead of affecting only
a single point on the metal M, as it would do if stationary, it covers a field equal
to the circumferential area of carbon A, thus rendering its action very efficient and
rapid.
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. The herein described mode of electrically heating metal consisting in springing

page_text: a voltaic arc between two electrodes one within the other, rotating said arc
magnetically, and applying said are to the article to be heated.
2. In an apparatus for electrically heating and welding by means of an electric
arc, the combination, with two concentric electrodes, of a magnet for directing and
steadying the arc, substantially as shown and described.
3. In an apparatus for heating and welding by means of the electric arc,
the combination of two electrodes one within the other, a support for said
electrodes and a magnet upon said support, and means for connecting said electrodes
and magnet with the terminals of a generator of electricity, substantially as shown
and described.
4. In an apparatus for heating and welding by means of the electric arc, the
combination of two electrodes, one within the other, an electro-magnet surrounding
said electrode and a support carrying said magnet and electrodes, substantially as
shown and described.
Dated this 17th day of July 1893
WM. P. THOMPSON & Co.,
Agents for the Applicant.