Apparatus for use in Manufacturing Electric Cables.
Year: 1892

page_text: Date of Application, 20th June, 1892)
Complete Specification Left, 20th Mar., 1893-4ccepted, 22nd Apr., 1893
PROVISIONAL SPECIFICATION.
Apparatus for use in Manufacturing Electric Cables.
I, GEORGE GATTON MELHUISH HARDINGHAM, of 191, Fleet Street, in the
City of London, Civil Engineer and Chartered Patent Agent, do hereby declare
the nature of this invention (a communication to me from the firm of Felten &
Guilleaume, of Mülheim on the Rhine, in the German Empire, Cable Manu-
facturers,) to be as follows:-
:-
This invention relates to apparatus for use in manufacturing electric cables the
naked conductors of which are, with a view to reducing the capacity," separated
by a strip of insulating material having grooves or channels forming air-spaces for
completing the insulation; the objects of the invention being to provide means for
folding the strip and for twisting the conductors and the strip together in the same
machine.
Apparatus constructed in accordance with the present invention comprises a
hollow shaft mounted to rotate in suitable bearings; the shaft being furnished
with a driving rigger. One end of the shaft carries a reel containing the blank
for producing the insulating strip (which is usually of paper). Four reels are
supported in brackets keyed to the shaft between the bearings. On these reels
are wound the naked conductors. A collar or disc is keyed on the end of the
shaft opposite to that carrying the blank-reel; the collar or disc rotating in
one of the aforesaid bearings. The collar is perforated with four diagonal holes.
The die for folding the strip is supported by a plate connected by four bars to
to the collar. Near the inlet, the bore of the die is, in transverse section,
octagonal; the sides being alternately concave and convex.
A radial web projects
from the eighth side and extends beyond the axis of the die. At a point near
the outlet, the bore is, in transverse section, in the shape of a cross; the web pro-
jecting through the centre of one arm and extending partly into the opposite arm.
The web does not reach to the outlet, which is also in the shape of a cross; the
arms of the cross being reduced in width to the requisite degree for forming the
finished strip. A second plate is secured by two bars to the first plate; the second
plate containing a cross-shaped aperture for the strip, and four holes for the naked
conductors near the angles of the cross. A drawing-out pulley is placed at a
convenient distance from the second plate; its periphery being on a level with the
axis of the die and of the hollow shaft.
The pulley draws the blank from the reel through the hollow shaft, through the
die and through the aperture in the second plate. At the same time, it draws
the four conductors from their reels, through the diagonal holes in the collar, and
through the holes in the two plates. The rotation of the hollow shaft carrying the
reels, die and plate twists the strip and the conductors together at the point where
they leave the second plate; each conductor lying in one of the grooves in the
strip. The core thus formed, after passing round the drawing-off pulley, is led to
a reel, whence it can be unwound as required.
Instead of a core consisting of a strip having four grooves and four conductors,
a core having a twisted strip with two conductors, one on each side, may be
formed in the same machine. In this case, only two reels for the conductors
are required, and the die and second plate are modified to suit the altered
conditions. Taking six transverse sections of the modified die, in the first the
bore is circular, with a small web; in the second, the bore is smaller, with a
larger web; in the third, the web nearly reaches to the opposite side of the bore;
in the fourth, the bore is V-shaped; in the fifth, the web disappears, the bore

page_text: being oval; and, in the sixth, the bore is rectangular. Thus the blank is first
curled into a circular form, and the edges are then bent inwardly until they
meet; the strip, when it finally emerges from the die, being flat and fourfold.
The modified second plate has a rectangular instead of a cross-shaped aperture.
The machine described above, instead of being independent, may form part of
apparatus in which the core is subjected to further treatment.
Dated the 20th day of June 1892
G. G. M. HARDINGHAM.
COMPLETE SPECIFICATION.
Apparatus for use in Manufacturing Electric Cables.
I, GEORGE GATTON MELHUISH HARDINGHAM, of 191, Fleet Street, in the
City of London, Civil Engineer and Chartered Patent Agent, do hereby declare
the nature of this invention (a communication to me from the firm of Felten &
Guilleaume, of Mülheim on the Rhine, in the German Empire, Cable Manu-
facturers,) and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
66
This invention relates to apparatus for use in manufacturing electric cables; or
cores therefor, the naked conductors of which are, with a view to reducing
capacity," separated by a strip of insulating material having grooves or channels
forming air-spaces for completing the insulation; the objects of the invention being
to provide means for folding the strip and for twisting the conductors and the
strip together in the same machine.
In the accompanying drawings,
Fig. 1 represents, partly in side elevation and partly in section, apparatus
adapted for use in the manufacture of electric cables or cores of the kind above
referred to.
Figs. 2 and 3, drawn to a larger scale, being respectively a side view and a
plan of the die and supplementary plate employed for folding the insulating
material into a grooved strip and twisting the same and the naked conductors
together.
Figs. 4 to 6 are respectively transverse sections of the die on the lines 4, 4, 5, 5
and 6, 6 in Fig. 2. These figures also illustrate the progress and gradual trans-
formation of the insulating material during its passage through the die.
Fig. 7 is a longitudinal view of a cable, or core therefor, produced by this
apparatus.
Figs. 8 and 9 show, in side view and in plan, a modified die and supplementary
plate adapted to fold the insulating material into a flat strip and twist the same
and two naked conductors together; Figs. 10 to 15 being respectively transverse
sections of the die on the lines 10, 10 to 15, 15 in Fig. 8.
Fig. 16 is a longitudinal view and Fig. 17 a transverse section of a cable or core
produced with the aid of the modified die and plate.
In the cable or core represented in elevation and transverse section respectively
in Figs. 18 and 19, the insulating material is star-shaped in cross section, and there
are six naked conductors; while, according to the mode of construction illustrated
in Fig. 20, there are eighteen conductors disposed in two concentric groups.
Apparatus constructed in accordance with the present invention comprises a
hollow shaft A mounted to rotate in suitable bearings B and B'; the shaft being
furnished with a driving rigger C. One end of the shaft carries a reel D containing
the blank d for producing the insulating strip d¹ (which is usually of paper).
Four reels are supported in bracketse keyed to the shaft A between the bearings B
and B'. Three reels E, E and E³ can be seen in Fig. 1; the fourth being,
however, hidden by the reel E¹. On these reels are wound the naked con-

page_text: Near
ductors e, e, e³ and e³. A collar or disc F is keyed on the opposite end of the
shaft to that carrying the blank-reel D; the collar or disc rotating in the
bearing B. The collar F contains four diagonal holes, of which two f and flare
visible in Fig. 1. The die G for folding the insulating strip is supported by a
plate H connected by bars I to the collar F. This plate contains four holes
(shown in dotted lines in Fig. 3) for the passage of the naked conductors.
the inlet, the bore of the die is octagonal, as represented in Fig. 4; the sides being
alternately concave and convex. A radial web y projects from the eighth side and
extends beyond the axis of the die. At a point near the outlet, the transverse
section of the bore is in the shape of a cross (as indicated in Fig. 5); the web g
projecting through the centre of one arm and extending partly into the opposite
arm. The web does not, however, reach to the outlet, the transverse section of
which is also in the shape of a cross (see Fig. 6); the arms of the cross being
reduced in width to the requisite degree for torming the finished strip d¹. A second
plate K is secured by two bars L and L' to the plate H; the second plate con-
taining a cross-shaped aperture ko for the strip, and four holes k, k', k² and k³, near
the angles of the cross, for the naked conductors. A drawing-out pulley M is
placed at a convenient distance from the plate K; its periphery being on a level
with the axis of the die G and of the hollow shaft A.
The pulley M draws the blank d from the reel D through the hollow shaft A,
through the die G and through the aperture k in the plate K. At the same time,
it draws the naked conductors e, e', e² and e³ from their reels, through the diagonal
holes in the collar F, and through the holes in the plates H and K. The rotation
of the hollow shaft A carrying the reels, die and plates twist the strip and the
conductors together at the point where they leave the second plate; each of the
conductors e, e, e² and e³ after the twisting operation lying in one of the grooves
in the strip. The core d² (Figs. 1 and 7) thus formed, after passing round the
pulley M, is led to a reel (not shown), whence it can be unwound as required.
Instead of a core consisting of a strip having four grooves and four conductors,
a core having a twisted strip with two conductors, one on each side, may be formed
in the same machine. In this case, only two reels for the conductors are required,
and the die and second plate are modified, as indicated in Figs. 8 to 15, to suit the
altered conditions. G¹ is the modified die. Taking six transverse sections of this
die, in the first (Fig. 10), the bore is circular, with a small web g'; in the second
(Fig. 11), the bore is smaller, with a larger web; in the third (Fig. 12), the web
nearly reaches to the opposite side of the bore; in the fourth (Fig. 13), the bore
is V-shaped in the fifth (Fig. 14), the web disappears, the bore being oval; and,
in the sixth (Fig. 15), the bore is rectangular. Thus the blank d is first curled
into a circular form, and the edges are then bent inwardly until they meet; the
folded strip d³, when it finally emerges from the die G', being flat and fourfold.
The modified plate K¹ has a rectangular aperture k* (Fig. 9), instead of the cross-
shaped aperture ko. d is the strip d³ after the twisting operation.
j
It is obvious that the present machine may also be further modified for producing
a cable or core consisting of a twisted insulating strip having three or more than
four grooves with a naked conductor lying in each groove; the folding die and
second plate being modified and the number of the reels altered accordingly. The
die may, for example, be formed so as to cause the strip d of insulating material to
assume the shape represented in Figs. 18 and 19; the twisted strip do having six
grooves containing six conductors e, e7, es, etc. The cable shown in Fig. 20 consists
of the strip and conductors illustrated in Figs. 18 and 19 surrounded by a strip d
having twelve grooves containing twelve conductors e, elo, ell, etc. The direction of
twist of the outer group of conductors e³, e¹, e", etc., is by preference opposed to
that of the inner group e, e², es, etc.
The machine described above, instead of being independent, may form part of
apparatus in which the core is subjected to further treatment. In Fig. 20, the
cable has been enclosed in a lead sheathing or other protective covering N.,

page_text: t Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I claim :—
1. Apparatus for use in manufacturing electric cables, and cores therefor, con-
structed or operating substantially as herein described, the same serving to twist
two or more conductors and a flat or grooved insulating strip in such a manner that
the conductors lie and are retained in the grooves formed in, or by the twisting of,
the insulating strip.
2. Apparatus for use in manufacturing electric cables, and cores therefor, con-
structed or operating substantially as herein described, the same serving to fold a
paper strip into a flat or grooved shape and then to twist the folded strip and two
or more conductors together.
3. In apparatus for use in manufacturing electric cables, and cores therefor, the
employment of a die, such as G or G¹, for folding a paper insulating strip,
substantially as herein described.
4. In apparatus for use in manufacturing electric cables, and cores therefor, the
combination, with a hollow shaft A carrying reels for the paper strip and the naked
conductors, of a die, such as G or G', and a plate, such as K or K', attached to
one end of the shaft, substantially as herein set forth.
Dated the 20th day of March 1893.
G. G. M. HARDINGHAM.