Improvements in Electrical Transformers.
Year: 1899

page_text: Date of Application, 19th Aug., 1899
Complete Specification Left 19th June. 1900-Accepted. 19th Nov., 1900
Improvements in Electrical Transformers.
I, ARTHUR FRANCIS BERRY, of 27, Woodville Road, Ealing, in the County of
Middlesex, Electrical Engineer, do hereby declare the nature of this invention
to be as follows:-
In the manufacture of electrical transformers it has heretofore been usual
to construct the primary and secondary windings of two or more independent
insulated conductors that have been separately wound in place in the trans-
former or have been formed into separate coils that have afterwards been placed
in the desired position in the transformer. These modes of construction are
costly and slow and moreover require considerable skill and care to ensure satis-
factory results.
Now this invention has for object to enable electrical transformers to be con-
structed in a cheaper, quicker and easier manner than heretofore and with less
dependence upon skilled labour. For this purpose the primary and secondary
windings of an electrical transformer are made from a cable composed of con-
ductors that are insulated from each other and are connected together at their
ends by suitable coupling devices in such manner that some of the insulated
conductors will be connected together in series or in parallel to form the primary
winding or windings and the remainder will be connected together in series or
in parallel to form the secondary winding or windings, the ratio between the
number of turns comprising the sets of conductors forming the primary and
secondary windings respectively being so designed as to give the desired ratio
of electrical transformation. The cross sectional shape of the cable and the
number and arrangement of the insulated conductors of which it is composed
and the method of insulation adopted can be variously modified as may be
desired. Conveniently the cable may be of circular section, the insulated con-
ductors to form one winding, say the primary winding, being arranged to form
the central portion of the cable and be enclosed within insulating material on
the outside of which the conductors to form the other winding, say the pri-
mary winding, are laid and then covered by an outer covering of insulating
material, the primary and secondary sets of conductors being thus arranged con-
centrically one within the other. In this case each of the outer insulated con-
ductors may be of segmental form and be composed of a number of bare wires
or strips arranged together in parallel. The cables may however be of square,
rectangular or other section if desired.
A length of cable such as described can be readily formed into a coil either
in situ in or on a transformer core or cores, or separately therefrom, and the
ends of the conductors to form each primary and secondary winding can be con-
nected together by coupling or connecting devices of various kinds so as to
place the conductors of each set in series or multiple series with each other and
produce the desired number of turns or convolutions in either or both the pri-
mary and secondary coils.
Primary and secondary windings formed by a cable as herein described caņ.

page_text: be used in the construction of electrical transformers of various kinds both of
the static type and of the rotary type. They may advantageously be used in
the construction of transformers having iron cores of the kind described and
shown in the specifications of former patents granted to me viz. No. 17526 of
1895, and Nos. 2801 and 9457 both of 1897.
improvements in Electrical Transformers.
I, ARTHUR FRANCIS BERRY, of 27, Woodville Road, Ealing, in the County of
Middlesex, Electrical 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:-
-
In the manufacture of electrical transformers it has heretofore been usual
to construct the primary and secondary windings of two or more independent
insulated conductors that have been separately wound in place in the trans-
former or have been formed into separate coils that have afterwards been placed
in the desired position in the transformer. These modes of construction are
costly and slow and moreover require considerable skill and care to ensure satis-
factory results.
Now this invention has for object to enable electrical transformers to be con-
structed in a cheaper, quicker and easier manner than heretofore and with less
dependence upon skilled labour. For this purpose the primary and secondary
windings of an electrical transformer are made from a cable composed of con-
ductors that are insulated from each other and are connected together at their
ends by suitable coupling devices in such manner that some of the insulated
_ conductors will be connected together in series or in parallel to form the primary
winding or windings and the remainder will be connected together in series or
in parallel to form the secondary winding or windings, the ratio between the
number of turns comprising the sets of conductors forming the primary and
secondary windings respectively being so designed as to give the desired ratio
of electrical transformation. The cross sectional shape of the cable and the
number and arrangement of the insulated conductors of which it is composed
and the method of insulation adopted can be variously modified as may be
desired. Conveniently the cable may be of circular section, the insulated con-
ductors to form one winding, say the primary winding, being arranged to form
the central portion of the cable and be enclosed within insulating material
on the outside of which the conductors to form the other winding, say the
secondary winding, are laid and then covered by an outer covering of insulating
material, the primary and secondary sets of conductors being thus arranged con-
centrically one within the other. In this case each of the outer insulated con-
ductors may be of segmental form and be composed of a number of bare wires
or strips arranged together in parallel. The cables may however be of square,
rectangular or other section if desired.
A length of cable such as described can be readily formed into a coil either
in situ in or on a transformer core or cores, or separately therefrom, and the

page_text: ends of the conductors to form each primary and secondary winding can be con-
nected together by coupling or connecting devices of various kinds so as to
place the conductors of each set in series or multiple series with each other and
produce the desired number of turns or convolutions in either or both the pri-
mary and secondary coils.
Primary and secondary windings formed by a cable as herein described can
be used in the construction of electrical transformers of various kinds both of
the static type and of the rotary type. They may advantageously be used in
the construction of transformers having iron cores of the kind described and
shown in the specifications of former patents granted to me viz. No. 17526 of
1895, and Nos. 2801 and 9457 both of 1897.
Figs. 1 and 2 of the accompanying illustrative drawings show respectively
in side elevation and plan a transformer the iron core of which is formed of
laminated iron plates built up and arranged as described in the specifications
of my said former Patent No. 9457 of 1897, and the winding of which is com-
posed of a length of cable of the kind herein referred to. Fig. 3 shows in
cross section and to a larger scale than Figs. 1 and 2, one form which the cable
may take. Figs. 4 and 5 are diagrams showing how the ends of the conductors
of which the cable is composed may be coupled together to form primary and
secondary windings.
In the example shown, the windings of the transformer consist of a single
length of cable arranged in two layers that extend through rectangular holes
in the laminated metal plates a, al constituting the iron core of the transformer,
the cable being composed of thirty seven inner conductors of circular section
that are numbered respectively from 1 to 37, forming the central portion of the
core, and are designed to serve as the primary winding or windings, and twelve
outer conductors of segmental shape that are numbered respectively from 38 to
49 and are designed to serve as the secondary winding or windings. Each of
the inner conductors 1 to 37 is separately insulated and the annular rows of
such conductors are insulated from each other and from the central conductor
by interposed layers of suitable insulating material so as to effectually sepa-
rate from each other adjacent conductors between which a considerable difference
of electrical potential may exist. Each of the outer conductors 38 to 49 is also
separately insulated and the whole of them are insulated from the inner con-
ductors by interposed insulating material c, and covered by an outer layer d of
insulating material. The ends of the several conductors in the example shown,
are led into a junction box made in two parts e and f, the ends of the inner con-
ductors 1 to 37 being led into and connected up in the lower part e of the said
box so as to place the several conductors in series with each other and form a
single primary winding, and the. ends of the outer conductors being led into and
connected up in any desired manner in the upper part f of the box to form the
secondary winding or windings. Fig. 4 shows diagrammatically how the two
sets of ends marked respectively 1 to 37 and 1b to 37 of the inner conductors 1
to 37 may be connected together. In this case, the end 1ª of the central con-
ductor 1 is connected to a terminal g by which it can be connected to one pole
of a source of alternating current supply. The other end 1b of this conductor
is connected by a junction piece 1* to the end 2 of the conductor 2, the opposite
end 2 of which is similarly connected by a junction piece 2* to the end 3 of the
conductor 3, and so on, so that the whole of the conductors 1 to 37 are connected
in series, the end 37b of the last conductor 37 being connected to another ter-
minal by which it can be connected to the opposite pole of the said source
of alternating current supply. When the ends of the conductors 1 to 37 have
been thus coupled together, which may be done by electric welding, the lower
part e of the box may be filled with a suitable insulating material either liquid
or solid.
The two sets of ends marked respectively 38 to 49 and 38 to 49b of the
outer conductors 38 to 49 and located in the upper part f of the junction box,

page_text: may be similarly connected together by junction pieces 38* to 48*, as shown
diagrammatically in Fig. 5, when it is desired to couple the whole of the outer
conductors in series to form a single secondary winding the ends of which are
connected to terminals hh. The junction pieces 38* to 48* may be detachably
connected to the ends of the conductors 38 to 49 so as to admit of such conduc-
tors being readily coupled up in any other desired order so as to form two or
more secondary windings, as may be desired.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is:-
:-
1. An electrical transformer the primary and secondary windings of which
are made from a cable composed of conductors that are insulated from each
other and are connected together at their ends in such a manner that some of
them will form the primary winding or windings and others. will form the
secondary winding or windings, substantially as described.
2. An electrical transformer having its primary and secondary windings com-
posed of insulated conductors arranged to form a cable and having their ends
coupled together, substantially as herein before described with reference to the
drawings annexed.
3. The improved electrical transformer hereinbefore described with reference
to and shown in the drawings annexed.
For the Applicant,
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C.,
Chartered Patent Agent.