Induction Resistance Coils.
Year: 1887

page_text: Date of Application, 11th May, 1887
Complete Left, 9th Feb., 1888
Complete Accepted, 23rd Mar., 1888
Induction Resistance Coils.
We WILLIAM MORRIS MORDEY Electrician and CHARLES EDMUND WEBBER, C.B.
Major General R.E. both of Victoria Works, Belvedere Road in the County of Surrey
do hereby declare the nature of our said Invention to be as follows:-
This Invention relates to improvements in electric transformers induction coils or
inductional resistance coils and has for its object to so construct such transformers or
coils that they are inexpensive and simple are not subject to undue heating, have a
high degree of efficiency and can be easily separated for examination or repair without
unwinding.
We will explain the Invention with reference to the accompanying Drawing
whereon Figure 1 is side view or plan Figure 2 a sectional elevation and Figure 3 an
end view of a transformer constructed according to this Invention but we premise
that we do not limit ourselves to the precise details illustrated. P P is the primary
wire or conductor and S S the secondary wire or conductor the relative sections
of which are in accordance with the inverse ratio of the tension of the inducing
and induced currents. Thus for example for the induction of a very large current
of low electro-motive force, such as would be required for electric jointing, or
welding, the secondary conductor may consist of a simple bar of copper bent into
the form of a long U. The said primary and secondary coils or conductors are
respectively connected to the terminals P P and S₁ 'S' and may be wound
either in two simple portions, as illustrated or in smaller portions alternating in
position or variously placed with reference to one another. A A are pieces of
thin sheet iron cach having an opening therethrough. B B are pieces of thin
sheet iron shewn as being without an opening through them. The pieces A and B
have an insulating substance between them on one side such as a coating of varnish
or a layer of paper. The pieces A are placed around or over the conductors P and S
and the pieces B are inserted between the pieces A so that the pieces A and B
alternate with each other as shewn. The pieces B pass through the coils of the
conductors as shewn in Figure 2 and are in contact with the pieces A. As there is
D
017

page_text: insulating material on one side only of the pieces A or B electrical contact only exists
between adjacent pieces on one side of each piece. Instead of the order described and
shewn two pieces A may be placed together then two pieces B and so on, the adjoining
pieces of the same kind being electrically separated so that there is only electrical
contact between two adjacent pieces of the different kinds so that whichever arrange-
ment be used eddy currents are prevented while magnetic continuity is secured. The
pieces are firmly secured which may be effected by clamping bolts and nuts & passing
through end plates E. The spaces between the pieces A. A and the spaces between
the pieces B B may be occupied by U shaped pieces of sheet iron. The end portions
of the coils may be occupied by slips of sheet iron varnished (or the like) on one side
and placed in the end portions of the coils at right angles to the pieces B B the outer
portions of the ends of the coils being covered by U shaped pieces of sheet iron
placed at right angles to the pieces A and meeting the slips of iron which occupy the
inner portions of the ends of the coils. In place of the pieces being formed as at A
and B they may be otherwise formed to give an equivalent effect for example they
may all be E shaped and be placed alternately with each other or two by two
alternately so that the mid-projections of the E shaped pieces pass through the coils
alternately from the two openings or ends of the coils. The said pieces when so
shaped are electrically separated on one side as hereinbefore explained.
In constructing large transformers or such as have a number of separate pairs of
coils the plates A may be made with a corresponding number of rectangular openings
each occupied by a primary and secondary coil. Similarly in such cases the E pieces
may be strips with a number of projections to be applied to the required number of
pairs of coils.
In constructing resistance coils for use with alternating or varying currents in
which it is desired to have a considerable inductive effect this form of apparatus is
used with but one coil or winding..
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W..,
Agents.
3

page_text: Improvements in Electric Transformers, Induction Coils, or
Inductional Resistance Coils.
We, WILLIAM MORRIS MORDEY Electrician and CHARLES EDMUND WEBBER C.B.
Major General R.E. both of Victoria Works, Belvedere Road in the County of Surrey
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 improvements in electric transformers induction coils or
inductional resistance coils and has for its object to so construct such transformers or
coils that they are inexpensive and simple, are not subject to undue heating have a
high degree of efficiency and can be easily separated for examination or repair without
unwinding.
Figure 1 of the accompanying drawings is a side view Figure 2 is an end view and
Figure 3 is a transverse section of one form of a transformer or coil constructed
according to this Invention. We do not limit ourselves to the exact details which we
have illustrated as certain of them can it will be evident be varied without departing
from the nature of our Invention. P P is the primary wire or conductor and S S is
the secondary wire or conductor the relative sections of which wires or conductors are
in the inverse ratio of the tension of the inducing and induced currents. Thus for
example for the induction of a. very large current of low electro-motive force such as
would be required for electric jointing or welding the secondary conductor may
consist of a simple bar of copper bent into the form of a long U. The said primary
and secondary coils or conductors are respectively connected to the terminals P¹ P¹
and S' S¹ and may be wound either in two simple portions as illustrated or in smaller
portions alternating in position or otherwise placed with reference to each other.
A A are pieces of thin sheet iron each having an opening a therethrough. One of
these pieces is shown separately in Figure 34. B B are pieces of thin sheet iron
without an opening through them. One of these pieces is shown separately in
Figure 3. The pieces A A or the pieces B B have an insulating substance on one
side such as a coating of varnish or a layer of paper. For the sake of ease of
manufacture and economy of material the pieces A and B may be so proportioned
that the pieces which are, stamped out in making the pieces A are the right size
for and may be used as the pieces B. The pieces A are placed around or over
the conductors P and S and the pieces B are inserted between the pieces A so that the
pieces A and B alternate with each other as shewn. The pieces B pass through the
coils of the conductors as shown in Figure 3 and are in contact with the pieces A.
As there is an insulating material on one side only of the pieces A or B electrical.
contact only exists, between adjacent pieces on one side of each piece. Instead of the
order described and shown two pieces A may be placed together, then two pieces B
and so on the adjoining pieces of the same kind being electrically separated so that

page_text: there is only electrical contact between two adjacent pieces of the different kinds so
that whichever arrangement be used eddy currents are prevented whilst magnetic
continuity is secured. The pieces are firmly secured which may be effected by
clamping bolts and nuts 6 passing through the cast end plates F F. The end plate
at F carries a frame f in which an insulating board or slab is supported on which
the terminals S¹ S¹ and P¹ P¹ are mounted. The opposite end plate F is shaped to
form a loop or ring which serves for carrying or suspending the apparatus. Both
the end plates F and F¹ are extended at e e to form feet. gg are light extensions of
the castings. For the purpose of avoiding eddy currents therein they may be blocks
of hard wood or other non-metallic material. These extensions or blocks are for the
purpose of pressing the iron strips together on the bolts & being screwed up. The
spaces between the pieces A. A and B B may be occupied by Ụ shaped pieces or slips
of sheet iron but it is preferred to leave them open in order to increase the ventilating
and cooling surface. The end portions of the coils may be occupied by slips of sheet
iron varnished (or the like) on one side and placed in the end portions of the coils at
right angles to the pieces B B the outer portions of the ends of the coils being covered
by U shaped pieces of sheet iron placed at right angles to the pieces A and meeting
the slips of iron which occupy the inner portions of the ends of the coils but generally
we prefer to dispense with these and therefore we have not shewn them in the
Drawing. In place of the pieces being formed as at A and B they may be otherwise
formed to give an equivalent effect for example they may be all E shaped as shewn in
Figure 4 and be placed alternately with each other or two by two alternately so that
the mid-tongues or projections of the E shaped pieces pass through the coils
alternately from the two openings or ends of the coils the projections or tongues
overlapping each of the adjacent ones. The said pieces when so shaped are electrically
separated on one side as hereinbefore explained.
In constructing large transformers or such as have a number of separate pairs of
coils the plates A may be made with a corresponding number of rectangular openings
each occupied by a primary and secondary coil and cross pieces B formed as herein-
before described. Similarly in such cases the E pieces (Figure 4) may have a
number of projections to be applied to the required number of pairs of coils.
Such a construction is shewn in end view in Figure 5 and in longitudinal section
in Figure 6. There are several pairs of primary and secondary coils (P and S) each
pair being embraced by portions of the È shaped iron pieces CC which are placed
in position as follows: Inside the coils or rings P S a number of the iron strips Care
placed having as many tongues or projections t t as may be necessary they extending
radially outwards between the pairs of coils. Similar strips C¹ are then placed on the
outer surface of the cylinder so formed the tongues or projections t¹ t¹ thereof
extending inwards and alternating in position with the tongues or projections t t of
the strips C. The double sets of strips (CC) thus form a number of closed magnetic
circuits around the conductors P S which may be wound in circular coils as shewn or
in elongated coils such as are shewn in Figures 1 to 4. When the circular form is
adopted as shewn in Figures 5 and 6 the strips C₁are conveniently arranged in
clusters placed in radial positions as shewn in the end view Figure 5 they being
supported in any suitable manner. This construction presents the advantage of very
short magnetic circuits. The several coils may be connected in series or in parallel as
may be desired.
In constructing resistance coils for use with alternating or varying currents in
*which it is desired to have a considerable inductive effect this form of apparatus is
used with but one coil or winding.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is:-
1. In electric transformers, induction coils and inductional resistance coils the
anlorment of the nieces A and B or the nieces bereinbefore called the "niacas”

page_text: 2. In electric transformers induction coils and inductional resistance coils the
combination of the pieces A and the pieces B or the pieces hereinbefore called the
E pieces" insulated so that one side only of each is in contact with the piece next it
as and for the purpose hereinbefore described.
"
3. The arrangement and combination of parts constituting the apparatus herein-
before described and illustrated in Figures 1, 2 and 3 of the accompanying
drawings.
4. The arrangement in electric transformers, induction coils and inductional
resistance coils of the strips C C¹ with their tongues or projections disposed as
herein before described.
Dated this 9th day of February 1888.
J. H. JOHNSON & Co.,
Agents.