Improvements in Heating by Electricity.
Year: 1890

page_text: Date of Application, 27th June, 1890
Complete Specification Left, 24'h Oct., 1890-Accepted, 29th Nov., 1890
Improvements in Heating by Electricity.
RANKIN KENNEDY 10 India Street Kilmarnock Scotland do hereby declare the
nature of this invention to be as follows :—
Hitherto electricity has been employed to raise the temperature of bodies by passing
an electric current from an external source through the bodies to be raised in
temperature.
And in cases where chambers vessels or receptacles containing liquids or substances
were to be heated or where non conductors of electricity were to be heated by
electricity resistance coils have been placed within or around them, these resistance
coils becoming heated on the passage of electric currents through them, imparted a
great portion of their heat to the vessel, chamber, receptacle or non conductor
surrounding them, or adjacent to them.
In all these methods hitherto employed for generating and applying heat produced
electrically for useful purposes in the arts and sciences, the electricity employed has
been in every case generated in an outside source and passed therefrom into the
body to be heated by actual electrical contact between the two These methods
are very difficult of application, the difficulties arising from the fact that in practice
the currents required for heating must be large in volume and therefore difficult
to manage and also from the fact that heat is produced in other parts of the
electrical circuit as well as in the body to be heated, and only a portion of the
whole energy is usefully applied.
According to this invention herein described the electricity which is converted into
heat to be usefully employed is produced directly by magnetism, generated by
alternating currents of electricity, which magnetism is produced, by currents drawn
from any source of alternating current of electricity.
The body, vessel, receptacle with their contents or chamber to be heated, is made of
iron in most cases, so that the magnetism may be applied directly to it, iron kettles
boilers, coffee pots, flat irons tailors-goose, soldering irons, and such like articles are
heated by placing them over or between or within an electro magnet having, a
luminated iron core, and through the coils of which is passed an alternating current of
electricity. The magnetism produced in these iron articles, by the alternating currents
in the magnet produces alternating currents within the masses of iron composing the
articles, the whole energy of these currents is converted into heat in the iron.
The currents of electricity supplied to the electro-magnet coils are drawn from any
source of alternating currents and are called the primary currents. The currents in
the articles to be heated circulate within their mass or body. The energy is conveyed
from the primary currents into the articles to be heated by inagnetism, and the
magnetism produces secondary currents therein. There is no actual electrical con-
nection or contact required between the articles or bodies to be heated and the primary
currents or source of electricity from which the energy is drawn to produce
the heat.
The articles or vessels with their contents to be heated are sometimes non magnetic,
and sometimes non conductors of electricity and also non magnetic-for example
brass, copper, and silver are conductors of electricity but are non magnetic. According
to this invention these and their contents are heated by placing thein in the magnetic
field of the luminated alternating magnet and placing an iron armature inside of them
to direct and concentrate the magnetism so that the secondary currents generated are
partly in the shell of the vessel or article and partly in the armature, both of them
becoming heated.
Glass, porcelain and clay vessels are non conductors as well as non magnetic., The

page_text: contents of vessels or articles made of these or similar substances are heated entirely
hy the secondary currents generated in an iron armature placed within the containing
vessel and so shaped and placed to concentrate and direct the magnetic flow from the
luminated alternating magnet, the magnetism passes readily through the non con-
ducting vessel or article and through the armature inside where it generates currents
in the armature and its coating, when that coating is conducting; these currents
become heat by conversion in the armature and in the coating or covering and this
heat is imparted to the article or vessel and its contents.
These iron armatures are thickly plated or encased in copper, silver, nickel,
platinum or enamel as circumstances require. Where a liquid is to be heated in a
vessel by this method; the armature in a copper kettle or boiler should be coated with
copper. A silver kettle should have a silver coated armature and so with other metals.
A water boiler heated according to this invention is constructed of copper or iron
tube, part of which is enclosed in a coil carrying the primary current, and the tube
contains soft, iron wires so arranged that the magnetic circuit enclosed by the primary
coils is complete or nearly closed, the secondary currents are generated directly in the
walls of the tube where they become converted entirely into heat.
The secondary coil of an alternating current transformer or magnet can be formed
of a copper tube joined to a vessel at its ends, the tube or vessel can be filled with
water or other substances to be heated, the secondary currents being generated in the
walls of the copper tube forming the secondary coil of the transformer or luminated
alternating magnet.
The luminated magnets are built of sheet iron stampings or soft iron wires and the
coils of insulated wire on them are in every case protected from radiated or conducted
beat by layers or packings of asbestos, mica, or other good incombustible non conductor
of heat.
DL1
en
.
T
RANKIN KENNEDY.
COMPLETE SPECIFICATION.
Improvements in Heating by Electricity.
I RANKIN KENNEDY Electrician 10 India Street Kilmarnock N.B. 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 has for its object improved methods of converting electrical energy
into heat to be used in the industrial arts and sciences.
Hitherto electricity has been employed to raise the temperature of bodies by passing
an electric current from an external source thro' the bodies to be raised in temperature
and in cases where chambers vessels or receptacles, containing liquids or other
substances, were to be heated or where non conductors of electricity were to be heated
by electricity resistance coils have been placed within or around them, these resistance
coils becoming heated on the passage of electric currents thro' them imparted a great
portion of their heat to the vessel chamber receptacle or non conductor surrounding
them or adjacent to them.
In all these methods hitherto employed for generating and applying heat produced
electrically for useful purposes in the arts and sciences the electricity employed has
been in every case generated in an outside source and passed therefrom into the body-
to be heated, by actual electrical contact between the two. These methods are very
difficult of application, the difficulties arising from the fact that in practice the currents
required for heating must be large in volume and therefore difficult to manage and
also from the fact that heat is produced in other parts of the electrical circuit as well
as in the body to be heated, and only a portion of the whole energy is usefully
applied.
According to my invention herein described the electricity which is converted into

page_text: heat to be usefully employed, is produced directly by magnetism, generated by
alternating currents of electricity, which magnetism is produced by currents drawn
from any source of alternating current of electricity.
The body, vessel, or receptacles with their contents, or chamber to be heated is
made of iron in most cases, so that the magnetism may be applied directly to it.
Iron kettles, boilers, coffee pots, flat irons, tailors goose, soldering irons and such
like articles are heated by placing them over, or between or within an electro-
magnet, having a luminated iron core, and thro' the coils of which is passed an
alternating current of electricity. The magnetism produced in these iron articles,
by the alternating currents in the magnet, produces alternating currents within
the masses of iron composing the articles, the whole energy of these currents is
converted into heat in the iron.
The currents of electricity supplied to the electro magnet coils are drawn from
any source of alternating currents, and are called the primary currents. The
currents in the articles to be heated, circulate within their mass or body. The
energy is conveyed from the primary currents into the articles to be heated by
magnetism, and the magnetism produces secondary currents therein; there is no
actual electrical connection or contact required between the articles or bodies to
be heated, and the primary current or source of electricity from which the energy
is drawn to produce the heat.
The articles or vessels with their contents to be heated are sometimes non
magnetic and sometimes non conductors of electricity and also non magnetic; for
example brass, copper, and silver, are conductors of electricity, but are non magnetic.
According to this invention these and their contents are heated by placing them
in the magnetic field of the luminated alternating magnet, and placing an iron
armature inside of them to direct and concentrate the magnetism so that the
secondary currents generated are partly in the shell of the vessel or article and
partly in the armature, both of them becoming heated.
Glass porcelain and clay vessels are non conductors as well as non magnetic ;
the contents of vessels or articles made of these or similar substances are heated
entirely by the secondary currents generated in an iron armature placed within
the containing vessel, and so shaped and placed to concentrate and direct the
magnetic flow from the luminated alternating magnet, the magnetism passes
'directly thro' the non conducting vessel or article and through the armature inside
where it generates currents in the armature and its coating when that coating is
conducting, these currents become heat by conversion in the armature, and in the
coating or covering, and this heat is imparted to the article or vessel, and its
contents.
These iron armatures are thickly plated or encased in copper, silver, nickel, platinum
or enamel, as circumstances require. Where a liquid is to be heated in a vessel by
this method, the armature in a copper kettle or boiler should be coated with copper.
Å
silver kettle should have a silver coated armature, and so with other metals. A water
boiler heated according to this invention is constructed of copper or iron tube, part
of which is enclosed in a coil carrying the primary current, and the tube contains soft
iron wires so arranged that the magnetic circuit enclosed by the primary coils is
complete, or nearly closed, the secondary currents are generated directly in the walls
of the tube where they become converted entirely into heat.
The secondary coil of an alternating current transformer or magnet is formed of a
copper tube joined to a vessel at its ends, the tube and vessel is filled with water or
other substances to be heated, the secondary currents being generated in the walls of
the copper tube forming the secondary coil of the transformer or luminated alternating
magnet.
The luminated magnets are built of sheet iron stampings or soft iron wires, and the
coils of insulated wire on them are in every case protected from radiated or conducted.
heat by layers or packings of asbestos mica or other good incombustible non conductor
of heat.

page_text: In order that others skilled in the art may understand more particulary my new
methods of electrical heating, I have hereunto appended a sheet of drawings.
Figs. 1 and 2 are diagrams showing the application of my invention to the heating
of smoothing irons.
Fig. 3 shows the manner of heating a copper kettle and its contents.
Fig. 4 shows a glass beaker to be heated with its contents.
Figs. 56. and 7 illustrate the application of the invention to heating a
soldering-bit.
Figs. 8 and 9 are two views of a water heater.
. Figs. 10 and 11 shows another form of heater.
Referring to Figure 2 M is an electro-magnet having a laminated core made up of
thin plates of iron secured together and sufficiently insulated from each other as in
the well known alternating current transformer.
Figure 1 is a sectional view of the same in which the conductor S is shown in
diagram as being wrapped round the middle limb of the magnet.
F is a common smoothing iron which is heated by being placed in contact with the
magnet so as to form with it a more or less closed magnet circuit. In this
manner heating currents are induced within the body of the smoothing iron itself as
indicated.
In Figure 3 is shown a copper tank or kettle mounted upon a magnet of substan-
tially the same construction as that described. An iron armature A is placed within
the kettle which armature should be plated with copper the arrows show the direction
of the induced magnetism, the glass beaker in Figure 4 is heated in substantially the
same manner, the armature A may be plated with any inoxidisable metal or enamel.
Figure 5 is a copper soldering-bit in which a mass of copper C envelopes
armature D.
an iron
Figs. 6 and 7 shew the manner in which this is placed in the magnetic circuit in
order to develop heat therein.
In this instance the magnetic influence is exerted principally upon the iron core
while the induced current is chiefly confined to the copper in which it is transformed
into heat.
Fig. 9 is an elevation and Figure 8 a section showing a vessel having a copper tube
connected with it in the form of a letter U the ends of which enter the vessel, this
tube forms the secondary of an alternating transformer, it passes through the slots in
the magnet core as shown in Figure 8 and the induced currents generated in its walls
are transformed into heat which is imparted to the liquid in the vessel.
In Figures 10 and 11 are shown in elevation and cross section another form of
heater made of wrot iron tubes and couplings. These tubes form the cores of the
magnet and constitute a closed magnetic circuit upon which the helix n. s. is wound.
The secondary currents are generated in the walls of the iron tubes and produce
heat therein, which is imparted to the liquid contents of the tube.
The drawings illustrate some of the most obvious applications of my invention but
many other adaptations to industrial uses may be made by those skilled in the art
without departing from the spirit of the invention.
An important advantage of this new method of heating is that the heat is generated
only in the body which is to be heated and my invention renders it possible to transmit
any required amount of energy for developing heat, through glass air wood and all
other bodies whether conductors of electricity or not.
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. The method substantially as hereinbefore set forth, of heating bodies by electrical
energy, which consists in producing magnetism by the influence of a pulsatory or
alternating current and thereby developing secondary currents within the magnetised
body whereby the same is heated as described.

page_text: 2. In an electro heating apparatus, the combination of a magnetic core and armature
which is within, or partly within and partly without the body to be heated with a
belix for magnetising said core and armature.
3. In an electro heating apparatus the combination of a laminated electro magnet
with coils of wire excited by pulsatory or alternating currents with an iron armature
placed inside of the body or liquid to be heated as herein described.
4. In an electro heating apparatus the combination of exciting coils carrying
alternating or pulsatory currents with a tubular iron core containing liquid to be
heated as herein described.
800
RANKIN KENNEDY.