Electric Cables.
Year: 1896

page_text: Date of Application, 11th May, 1896
Complete Specification Left, 11th Feb., 1897-Accepted, 20th Mar., 1897
PROVISIONAL SPECIFICATION.
Improved Electric Cables.
1, GEORGE HINDE NISBETT, of Ashfield, Huyton, in the County of Lancaster,
Electrical Engineer, do hereby declare the nature of this invention to be as
follows:-
In making twin or 3 core cables hitherto, difficulties have been met with in their
manufacture; or, the cable when completed has been of an unmechanical form, and
expensive to make, besides having other defects. In twin and 3 core cables as most
commonly made, it is customary to take the ordinary round stranded conductor con-
sisting of 7, 14, or more wires twisted together, and to give to this a coat of insulating
material; and then two or more of these cables thus made are stranded together.
Now by thus twisting two or three round cables together, the resultant form of the
cable is more or less triangular or oval; and if the whole is covered with a round
sheath of metal, as is usual, a lot of waste space results, thereby increasing the quantity
of lead used in the sheathing, and consequently the cost of the cable: besides having
a three corner or oval combination in a round sheath, in which the covering is not
supported mechanically, and large spaces are left for the entrance of moisture from
the end of the cable.
Now according to my invention, the conductors are so shaped and insulated, and
arranged, that when they are laid together, they form a round or substantially round
combination and cable, thereby providing a relatively small cable over all.
I am aware of what has been proposed by the Specification of the Patent No. 22923
of 1892 of Ferranti, and by the Specification of the Patent No. 7782 of 1893 of
Hardingham. In cables however according to my invention, the ordinary stock sizes
of round, solid, or stranded conductors are employed, and these are so disposed that,
together, they make up the required shape of compound conductor. In one case, in
a twin cable, each line is required to be approximately of semicircular shape; this
shape is produced by making each line of three conductors, placed side by side, the
middle one being of larger diameter than the other two; or, five, or seven wires of
varying sizes are so placed together, and so disposed, as to form a semicircular shape.
In three core cables, three or four round wires of varying sizes are employed, and so
disposed as to make the complete conductor formed by them more or less into a
triangular shape. In all cases, in flexible cables under this invention the completely
insulated cores are laid up together with a more or less rapid spiral.
I would have it understood that in making any of these compound conductors,
either solid wires, or stranded conductors may be used as the units; or, a combi-
nation of the two may be used. For instance, all the wires could be solid, or the
large ones stranded and the small ones solid, or all stranded.
In the manufacture of the cables, the combinations of wires to form the complete
conductor are held in their relative positions while being insulated, by means of
suitable dies.
The chief advantages afforded by my invention are, ease of manufacture; the
avoidance of the use of specially drawn copper; the use of a large number of wires
or segmental pieces is avoided; a flexible cable is assured; any of the ordinary
methods or means of insulating a cable now in vogue can be employed without
difficulty; special twisting and handling of the paper or other insulating material is
avoided; and also, the use of a multiplicity of wires or small segmental pieces, and

page_text: the difficulty and expense of handling and holding them in place while being insulated
is avoided.
As a modification of cable under this invention, the stranded wires used in, or
forming the conductors, are pressed or crushed to the desired form, to obtain the
characteristics or qualities of the cable above referred to; this shaping being con-
veniently done by passing the stranded wires through a die or dies or rollers of the
required form; and in some cases, after being so treated, they may be annealed.
According to a further modification, I produce a flexible segmental solid duplex, or
like cable of small size. In this small cable, the two (or more) solid conductors-of
the special segmental form required to produce a circular cable when completed-are
insulated from one another and on the outside by suitable insulating material, and
bave a spiral turning or twist-more or less rapid-about each other. This particular
construction produces or provides a practical, and serviceable small flexible cable.
Dated this 9th day of May 1896.
CHEESBROUGH & ROYSTON,
15 Water Street, Liverpool, Applicant's Patent Agents.
I, GEORGE HINDE NISBETT, of "Ashfield," Huyton, in the County of Lancaster,
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 making twin or 3 core cables bitherto, difficulties have been met with in their
manufacture; or, the cable, when completed, has been of an unmechanical form, and
expensive to make, besides having other defects. In twin or 3 core cables, as most
commonly made, it is customary to take the ordinary round stranded conductor, con-
sisting of 7, 14, or more wires twisted together, and to give to this a coat of insulating
material; and then two or more of these cables thus made are stranded together.
Now, by thus twisting two or three round cables together, the resultant form of the
cable is more or less triangular or oval; and if the whole is covered with a round
sheath of metal, as is usual, a lot of waste space results, thereby increasing the
quantity of lead used in the sheathing, and, consequently, the cost of the cable :
besides having a three corner or oval combination in a round sheath, in which the
covering is not supported mechanically, and large spaces are left for the entrance of
moisture from the end of the cable.
Now, according to my invention, the conductors are so shaped and insulated, and
arranged, that, when they are laid together, they form a round or substantially round
combination and cable, thereby providing a relatively small cable over all.
I am aware of what has been proposed by the Specification of the Patent,
No. 22923 of 1892, of Ferranti, and by the Specification of the Patent, No. 7782
of 1893, of Hardingham. In cables, however, according to my invention, the
ordinary stock sizes of round, solid, or stranded conductors, are employed, and these
are so disposed that, together, they make up the required shape of compound
conductor. In one case, in a twin cable, each line is required to be approximately
of semicircular shape; this shape is produced by making each line of three
conductors, placed side by side, the middle one being of larger diameter than the
other two; or, five, or seven wires of varying sizes are so placed together, and so
disposed, as to form a semicircular shape. In three core cables, three or four round
wires of varying sizes are employed, and so disposed as to make the complete
conductor formed by them more or less into a triangular shape. In all cases, in

page_text: flexible cables under this invention, the completely insulated cores are laid up
together with a more or less rapid spiral.
I would have it understood that, in making any of these compound conductors,
either solid wires, or stranded conductors may be used as the units; or, a com-
bination of the two may be used. For instance, all the wires could be solid, or
the large ones stranded and the small ones solid, or all stranded.
In the manufacture of the cables, the combination of wires to form the complete
conductor are held in their relative positions, while being insulated, by means of
suitable dies.
The chief advantages afforded by my invention are ease of manufacture; the
avoidance of the use of specially drawn copper; the use of a large number of wires
or segmental pieces is avoided; a flexible cable is assured; any of the ordinary
methods or means of insulating a cable now in vogue can be employed without
difficulty; special twisting and handling of the paper or other insulating material is
avoided; and also, the use of a multiplicity of wires or small segmental pieces, and
the difficulty and expense of handling and holding them in place while being insulated,
is avoided.
As a modification of the cable under this invention, the stranded wires used in, or
forming the conductors, are pressed or crushed to the desired form, to obtain the
characteristics or qualities of the cable above referred to; this shaping being
conveniently done by passing the stranded wires through a die or dies, or rollers
of the required form and in some cases, after being so treated, they may be
annealed.
According to a further modification, I produce a flexible segmental solid duplex or
like cable of small size. In this small cable, the two (or more) solid conductors-of
the special segmental form required to produce a circular cable when completed-are
insulated from one another, and on the outside, by suitable insulating material, and
have a spiral turning or twist-more or less rapid-about each other.
particular construction produces, or provides a practical, and serviceable small flexible
cable.
This
The invention will be set forth with reference to the accompanying drawings, in
which several special forms of cables are given, and these different special constructions
I will describe successively. In the drawings the same or equivalent parts, wherever
they occur, are marked with the same letters and figures of reference; and it is to be
understood, that these parts which are provided with letters or figures, but not
specifically referred to in the description of the different modifications, must be taken
to be the same as, or similar to those described in the case in which the parts referred
to by said letters or figures are described.
Referring to Figure 1, in this a three core cable is shewn, the three lines each
consisting of three solid or stranded conductors, or wires, a, namely, a central large
conductor, and two smaller conductors in the angles of the space within the insulation.
The conductors a, when formed of stranded wires, may be made up of a different
number of wires in each, or different sizes of wires, or both. The insulating septa
dividing the cables into separate lines are designated b, and this insulation is also
carried round at the outside at b. The insulation 6 b' may be of paper, gutta-percha,
india-rubber, or any other suitable material, and applied about the conductor by
winding insulating material about the wires forming the separate lines or enclosing
them by "squirting," according to the type of insulation used, or by any combination
of such methods. When a flexible cable is required, the lines are separately enclosed
in insulating material or coverings as specified, they are placed together into the
relative positions shewn in the figure, and then twisted together in the form of a
cable, and enclosed in an outer covering, as lead. This outer covering is represented
in the drawings by the annulus c.
The wires or strands forming each conductor in these cables in their manufacture are
laid parallel with each other and without twist, but in the cable the three complete
insulated compound conductors are given a suitable twist round each other of desired
pitch, so as to render the complete cable capable of being bent without distorting,

page_text: or moving out of place, any of the wires or conductors, as would happen were there no
twist or pitch.
The cable shewn in Figure 2 is of a triple line type, similar to that shewn in
Figure 1, having each line made up of four equal sized solid or stranded conductors a,
arranged in relation to each other as shewn in the figure.
The cable shewn in Figure 3 is another modification of triple line cable, the
modification consisting in making each line of two large and one small solid or
stranded conductors a.
The special arrangement of conductors of the cables thus far described, and shewn,
may, if desired, be carried out in connection with or applied to quadruple and
quintriple line cables.
The cable shewn in Figure 4 is of the twin type, and consists of two lines divided
by a septum of insulating material, the insulation also being carried round outside
at. b. Each line in this cable consists of one large and two smaller solid or stranded
conductors a, having the relative positions in the cable, as shewn.
Figure 5 shews a modified duplex cable, in which the lines each consist of two
larger conductors and one smaller conductor a, disposed in the insulation of the
cable, as shewn.
Figure 6 shews another duplex cable; in this there are five conductors in each
line, three large and two small, the three large conductors being next the septum b,
and two smaller ones, outside.
The next modification shewn in Figure 7 is a duplex cable, in which the two
lines on either side of the septum are comprised of 7 conductors, there being
four larger conductors in a row next the septum, and one central large conductor,
and two smaller conductors, on the outside of these.
Figure 8 shews a modification of the cable sbewn in Figure 7, the modification
consisting of the two lines being composed of seven conductors all of the same
size.
It is to be understood that the characters of the form or construction of the
conductors a, and of the insulation, specified in the description of the cable shewn
in Figure 1, applies to all the cables shewn and described.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
The herein described multiple core cables, such cables consisting of a number of
compound conductors insulated from one another, and externally, by suitable
insulation, and each core being made up of the forms or sizes, arrangement, and
numbers of conductors, as herein set forth, and as shewn in the several figures of the
drawings, respectively.
1
1007
CHEESBROUGH & ROYSTON,
15 Water Street, Liverpool, Applicant's Patent Agents.