IMPROVEMENT IN LEAD ARMORED ELECTRIC CABLES, AND IN MANDRELS FOR MANUFACTURING THE SAME
Year: 1884

page_text: I, RICHARD S. WARING of Pittsburg, County of Allegheny, State of Pennsylvania,
United States of America, Electrical Engineer do hereby declare the nature of my
Invention for "IMPROVEMENT IN LEAD ARMORED ELECTRIC CABLES, AND IN
MANDRELS FOR MANUFACTURING THE SAME and in what manner the same is to
be performed to be particularly described and ascertained in and by the following
statement:-
The first part of my Invention relates to lead armored electric cables and is
illustrated on Sheet 1 of the accompanying Drawings in which:
Figures 2 and 4 are transverse sectional views of my improved cable.
Figures 1 and 3 are perspective views of the same.
My Invention relates to certain improvements in metal covered cables, and in
general terms it consists of a cable having its insulated conducting wires enclosed
in separate tubular passages in a common body of inetal, the wires being arranged
in a novel manner or method, whereby flow of metal to form the inner walls of
covering around the wires is facilitated, and my Invention further consists of a
cable having a body or covering of metal with a number of tubular passages
therethrough within which the insulated wires are enclosed, such wires being
arranged in pairs of rows, the two rows of a pair being in closer proximity than
the adjacent rows of succeeding pairs, and also closer than the adjacent wires, in a
single row, as hereinafter more fully described and claimed.
In the manufacture of lead covered electric cables it is customary to make use
of a lead press, so called; the insulated wires being passed through the tubular core
or mandrel and through the die, the lead being applied under pressure as an armor
or covering to the wires, within the die at the point or points of the wire enclosing
core.
Also, in the class of cables to which my present Invention belongs, each wire
is surrounded or enclosed and separated from others in the cable by continuous
solid or unbroken body or wall of metal, such metal covering serving the double
purpose of a protective covering shielding the insulated wires from external injury
and also preventing disturbance from electrical induction, so called. The protection
thus afforded, from induction, is practically complete, and this is the case even

page_text: though wires be in close proximity, closer than it has been found to be practical
to arrange them and secure the complete or intact lead covering requisite with
means or methods heretofore employed. It is very desirable that as close and
compact arrangement of wires be made as may be possible, in order to secure
economy in the use of lead and also in space occupied by the cable. It is also
desirable and often required that a single cable should contain a considerable
number of wires. A practical limit to the proximity of wires has been encountered,
however much short of what is desired.
This has arisen from the difficulty of forcing sufficient amount of lead between
the nipples of the mandrel to secure the essential condition of continuous, unbroken
enveloping of the wires throughout the interior portions of the cable. This
difficulty is greatly increased by multiplication of the number of wires arranged in
a given space, and, as above stated, has imposed a practical limit upon the
proximity of the wires, much short of what is desired and might otherwise be
permissible.
The purpose of my present Invention is to provide, in the arrangement of the
wires in the cable, for much closer grouping of wires than heretofore, and in so
doing to secure the requisite characteristics of continuous unbroken covering or
enclosing walls, with such degree of economy in construction as to bring a cable
containing a comparatively large number of wires within, the limits of commercial
success. To this end a-cable is made by means of a press, of the class above
referred to, such cable having a homogeneous body of metal covering A by
preference of lead, through other equivalent soft, ductile metal or alloy may be
employed capable of being formed into a homogeneous covering. by means of a
press. Within this body of metal are formed tubular passages a, by means of
tubular nipples on the core or inandrel, which nipples individually considered may
be constructed, and operated.as commonly practiced in the art. Within these
passages are enclosed the insulating conducting wires c, e, of the cable.
The special feature of construction in this connection is the relative arrangement
of the wires within the lead body A, consisting of an arrangement of the wires in
two rows, the wires c forming one such row and the wires e the other row. "The
wires in the two rows alternate: that is, the wires in one row are at intervals
about midway between the. wires of the other, and the lines of the two rows are
nearer together than the individual wires of each row, so that the space or distance
between any two adjacent, wires, in the same row, is greater than between any two
adjacent wires taken in the two, different rows. Or in, other words, the passages
through which lead flows from the exterior to the interior, are widest or, most open
at the surface and most contracted in the centre where the lead entering, from
opposite points naturally meets and forms adhesive union, under pressure, around
the inner surfaces of, the wires.
j
This provision in the arrangement of wires in a cable, containing other than a
single plane or row, materially facilitated 'the flow of lead into this centre and
ensures intact homogeneous walls of covering, in such interior, with closer
proximity of wires than can be secured by-methods of arrangement heretofore
practised.
Substantially the same feature of grouping the wires in pairs of rows, with the
adjacent wires of the two rows in closer proximity, than.the adjacent individuals of
either row may be incorporated into larger cables containing more than one pair.
of rows, see Figures 3 and 4.
.15
•
4444.
In these Figures the insulated conducting wires, cand e are arranged or grouped
in pairs of rows, the wires c forming one row of each pair, and the wires e, the
other row of each pair. The two rows constituting such a pair are in close
proximity, or closer than the adjacent rows. of successive pairs; also the
individual wires, in a pair of rows alternate in order, that is, the wires c occur
about midway of the intervals between the wires e, and the adjacent wires c and, e
in the two rows of a pair, are in closer proximity, than the adjacent wires ccore e
of either row. By these features of arrangement, comparatively wider passages, as

page_text: at 1, are secured between pairs of rows, and also between the adjacent wires of each
row, as at 2, and lead may flow with comparative freedom along these widened
passages or channels till the point of closest proximity of wires as at 3, which are
at or near, the points of meeting of the lead entering from different directions
through, or along the several channels.
Another feature of arrangement which I employ in this connection is to make
the adjacent rows in successive pairs correspond in number and order of position of
wires, so that the wires in such rows occur in common transverse lines and do not
alternate as to the wires in two rows in close proximity, composing a pair. This
arrangement groups the wires in two adjoining pairs approximately in circles of
six (see Figure 4) the enclosed area of such a circle being supplied with lead
through the widened channels between pairs of rows; such circular area serves, in
a measure, as an inner channel through which or from which the lead is 'applied to
the inner surfaces of the several surrounding wires, so that viewed in that form or
feature of grouping substantially the same feature of advantage is secured as above
described, namely; comparatively wide channels for lead to flow to the interior
of the cable, and a direct application of lead from such channels to the major part
of the wire surfaces which are exposed to such channels on all sides except
adjacent to the nearest wire in the companion row of the pair, and these points
of closest proximity of wires correspond to the point at which union is formed
between supplies of lead entering from different directions. Properly speaking,
therefore, lead does not flow through, but into these narrowest spaces.
་
The alternate succession of wires in a pair of rows is an important feature in
this connection because by means of it, each individual wire is exposed in opposite
sides in the direct lines of lead flow leaving but a comparatively small amount of
surface on each wire to be covered between closely approximating wires.
By grouping or arranging the wires in this manner, flow of. lead from the
surface to the interior of the cable is materially facilitated and in securing this
increased facility, no sacrifice is made in the number of wires included in the cable,
on the contrary the number which can in this improved arrangement be covered
successfully in a given area of section, is actually much greater than could be
included in the same area as heretofore arranged because the difficulties heretofore-
encountered in securing lead supply to the interior of the cable are greatly reduced
or overcome. These features of improvement are also of material advantage in
the construction of the core or mandrel for a cable containing many wires.
The second part of my Invention relates to mandrels to be used in
manufacturing lead armored electric cables, and' is illustrated on Sheet 2 of the
Drawings in which:
3
- C
Figure 1 is an end view of my improved mandrel or core.
:
Figure 2 is a transverse sectional view, taken in the plane of the line X X,
Figure 4 looking towards the nipples or point.
Figure 3 is a similar view taken in the plane of the line X1 X1, Figure 4, looking
away from the nipples or point.
Figures 4 and 5 are longitudinal sectional views taken in the planes of the
lines Y Y, and Z Z respectively of Figure 2.
Figure 6 is a view in sectional elevation, the plane of section being indicated by
the line Z Z³.
6
-
Figure 7 is a transverse sectional view of the cable.
1
Figures 8, 9, 10 and 11 are views similar to Figures 1, 2, 4 and 5 respectively
but showing the Invention applied to a mandrel for making a cable shewn in
Figure 13 in transverse section.
ST
Figure 12 is a view in side elevation of the mandrel shewn in Figures 8. 9.-10
and 11.
''
7.
Figure 15 is a transverse sectional view taken in the plane of the line' X X
Figure 18-looking toward the point.
C
Figure 14 is an end view of a modification of my improved mandrel looking
upon the point.

page_text: Figures 16 and 17 are longitudinal sectional views of the mandrel and die taken
in the plane of the lines Y. Y. and Z. Z. respectively of Figure 14.
Figure 18 is a view, in side elevation, of the mandrel with a sectional view of
the die.
Figure 19 is a plan view of the die.
Figure 20 is a sectional view of one form of cable made by my improved
mandrel.
This part of my Invention relates to certain improvements in the core or mandrel
employed in a lead press for making compound, lead-covered, electric cables, and
in general terms it consists of a mandrel, having on its point or core-end tubular
nipples arranged in one or more pairs of rows, the two rows of a pair being in
close proximity with provision for passing lead between pairs of rows and between
adjacent nipples in the several rows. My Invention further consists of a mandrel
having wire passages therethrough, and a guard or shield at the point combining
with the die, to admit lead supply to the wires at certain points as hereinafter
..more fully described and claimed.
I have illustrated my Invention embodied in mandrels of two different forms,
adapted to form two cables, one, as in containing a single pair of rows of wires,
and the other containing four such pairs.
When the wires of a cable are few in number and arranged in a single row or
in similar simple order no special difficulty is encountered in covering the same
with lead in a lead press even when such wires are in close proximity. But cables
of the class referred to are often required in the art containing a large number of
wires; also, economy in the use of lead and other requirements of commercial
success make it important that such cables should be as small in sectional area,
and as light as may be. The difficulties heretofore encountered in securing a
continuous unbroken body of lead between contiguous wires, have prevented close
grouping of wires, and consequently have necessitated the construction of large
and heavy cables and the use of large amounts of lead in such construction.
These have proved serious hindrances to the successful manufacture and use of
large cables and my Invention is designed more particularly to overcome these and
other-like difficulties.
+
My improved mandrel is constructed as follows:-
A body of metal A of iron or steel, is tapered toward one end, forming the point
of the mandrel.
A threaded socket a is formed in the base-end for attachment to the threaded
end of tabular core bar B or other equivalent tabular support which with the
socket in mandrel A encloses a chamber or larger passage A Through the body
of the mandrel are formed a number of holes a through which the wires are
passed.
In drilling these holes they may be arranged in any desired order of distribution
at the base end, opening into chamber A¹ but they are given such directions that at
the point they emerge in the order of one or more pairs of rows corresponding
to the arrangement of wires s. s'. in cable S Figure 13 or of wires r. r. in cable R
Figure 7.
In order to form tubular nipples, or pipelike extensions e. e¹. through which the
wire passages emerge, grooves c (see Figures 3. 5. and 6) are cut in the point
between successive pairs of rows thus dividing the point of the mandrels into two
or more parallel lands or sections C each perforated with two lines or rows of wire
passages The grooves c may be of any desired depth by preference somewhat
greater than the length of nipples to be made, and the bases of these cuts or grooves
may be rounded or inclined from the centre toward either side so as to facilitate
entry or flow of lead into the same.
In the metal thus divided or separated are formed the nipples e el by turning or
otherwise cutting away a portion of such metal leaving comparatively thin pipe-
like or cylindrical projections forming extensions of the wire passages, with open
spaces i.Figure 4 between the several extensions or nipples thus formed.
+

page_text: The depth of these cuts or spaces i is by preference about one quarter inch, and
about one half of the depth of grooves c (see Figure 5).
In operation, lead, in its passing under pressure out of the cylinder, of the press,
enters and fills the grooves c, passing downward therein to the die opening. In
passing the nipples e e' these streams of flowing lead pass or expand laterally in
to the spaces immediately surrounding the nipples and such supply coming from
both sides of each pair of rows unites around the nipples under the pressure to
which the lead is exposed, and so passing downward off the points of the nipples
envelope the several wires within the passages formed in the lead body by the
nipples, which latter, in their function of forming passages, operate substantially
like the core of an ordinary pipe press.
In order to facilitate the lateral flow of lead from the grooves c into the spaces i
surrounding the nipples, the 'shoulders 2 (see Figures 5 and 6) are bevelled or
countersunk provision being made for this in the arrangement of the nipples as
presently described.
By making the nipples e e' comparatively short, requisite strength is secured
with comparatively light or thin walls, and by making the grooves c deeper than
the nipples provision is made for obtaining a full unbroken stream or supply of
lead in such grooves from which the lead spreads throughout all the spaces i
surrounding each and all the nipples, under substantially the same conditions.
The arrangement of the wire enclosing nipples is also an important feature in
this connection As shown in the Drawings, this arrangement is in pairs of rows,
the nipples e representing or constituting one row of each pair and the nipples e¹
the other row of the pair. These two rows constituting a pair are in close
proximity and the nipples e of one pair alternate in position with or occur about
midway of the intervals between the nipples e¹ of the companion row Also
adjacent nipples in each row that is successive nipples e e or el e¹ are separated by
greater intervals than adjacent nipples e. e. measured across the rows. These
features of arrangement afford comparatively wide openings (see Figure 1) for lead
to enter the spaces & from the grooves or channels c and also exposes the greater
part of the nipple surfaces to the direct flow of lead for these channels. In this
manner the wires may be grouped compactly in pairs of rows in the cable and at
the same time provision is made for distributing the lead supply uniformly
throughout the entire group before it reaches the points where it envelopes the
wires by direct contact therewith. This feature of forming channels for lead
passage at intervals through the body of the mandrel in order to distribute the
lead supply before it reaches the nipple proper, is of special importance and
advantage where more than one pair of rows of nipples are required By means
of this provision lead is applied to each successive pair of rows of nipples, be they
more or less under substantially uniform conditions throughout, such conditions
being also substantially the same where a single pair of rows is employed. In this
form of mandrel the grooves c. of Figure 3 are not used because not needed, the
flow of lead along the outer, tapered surface of the mandrel affording uniform supply
to all the spaces i surrounding the nipples. In other respects the principles of
construction and arrangement involved in the mandrel having the single and that
having more than one pair are substantially the same.
b
Another feature in the arrangement of nipples, relating more particularly to
mandrels containing two or more pairs of rows, is the order of succession of rows
(see Figure 1). As there shown, the adjacent rows of any two successive pairs
have the same number and order of position of nipples or in other words rows,
containing an even number of nipples are immediately succeeded in the next pair
by a similar row and likewise the rows containing an odd number are similarly
succeeded, whereby a regular surface outline is secured for the cable and also the
nipples of two adjoining pairs of rows are naturally grouped into approximately
circular arrangement of six nipples in each such group. This arrangement not
only facilitates access to the spaces between nipples to countersink the shoulders 1
as above described and to do other like work in construction and fitting but also
11.
T

page_text: more open or un-obstructed, passages are secured for flow of lead both toward the
nipple points and laterally-into the spaces immediately surrounding the nipples.
At the point of the mandrel may be, made a recess C. forming thereby an
extended rim c. c² surrounding the openings to the wire passages. The side rims c¹
are cut out in part forming opening c³, through which lead flows to and around
the wires. At and near the edges the rims c² are extended so as to enter
correspondingly shaped recesses e² in the die. The rims 2 fit closely in the recesses
and thereby, and thereby hold the die and mandrel in fixed relationship. The inner
surface of these rim extensions c² are in effect portions of. the die and operate as
such in giving shape to the exterior surface of the cable and they also perform the
function of preventing lateral displacement of the die and mandrel as above stated.
This I consider an important feature of improvement and ensures a more uniform
covering in the cable than can be secured when the mandrel and die.are wholly
separate and may move laterally in relation to each other. The die Etogether with
that part of it formed by the rim extensions c² operates in compressing the, lead so as
to cause it' to make adliesive union around the wires and also in shaping the
exterior of the cablé substantially as the corresponding devices heretofore.
employed..
As lead is forced out of the cylinder of the press it will enter the recess C.
around the wires and filling the same, will. pass outward through the die carrying
the wires along with it completely.embedding the latter in the body of metal so
delivered from the press.
While I prefer for the reasons above given to make the rim extension c² of
sufficient length to enter corresponding recesses e² in the die, still I do not wish to
limit my Invention by this specific feature of improvement because the mandrel
may be and has been used by me with good results with the extensions c² resting
on the face of the die. This is especially the case when suitable provision is made
in other ways for preventing lateral displacement of the die and inandrel.
In either of these cases the rims c2 prevent direct flow and pressure of lead upon
the wires in the direction of the rows in which they are arranged and in this
respect also they are of material advantage and importance because such pressure.
if it existed un-resisted would tend; injuriously to bunch the wires by deflecting
them out of proper alignment.
A special feature of advantage secured by this Invention is the provision made
thereby för bringing the wires into such a relationship as to make a cable of given
area in cross section to contain a comparatively large number of wires. By means
of the rim c¹ c¹ the wires are suitably protected from direct flow and pressure of
lead and by omitting the nipples ordinarily employed in this class of mandrels a¹
may be brought much closer together.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is :-
First. A compound electric cable having an integral homogeneous body or
covering of lead or equivalent soft ductile metal or alloy with insulated wires
enclosed in separate passages therethrough such wires. being arranged in two rows
the adjacent wires of the two rows being in closer proximity than the adjacent
wires of either row, substantially as set forth.
Second. A compound electric cable having an integral homogeneous body of
metal covering with insulated wires enclosed in separate passages therethrough
such wires being arranged in two rows the adjacent wires of the two rows being
in closer proximity than the adjacent wires in either.row and the wires of one row
alternating in order of position with those of the other row substantially as set
forth.
Third. The method of arranging wires in compound cables, formed in a lead
press consisting in grouping them in two rows the individual wires of one.row.
alternating with those of the other row, and the adjacent wires of each row being
separated a greater distance than the adjacent wires of the two rows substantially

page_text: as described whereby lead passages are formed between wires of increasing width
from the centre of the cable or group of wires outward and flow of lead to the
centre is facilitated.*
Fourth. An electric cable having a body or protective covering of soft ductile
metal or equivalent alloy, with tubular passages therethrough enclosing insulated
conducting wires such wires being arranged in pairs of rows the two rows composing
a pair being in closer proximity than successive pairs, substantially as set forth.
Fifth. An electric cable having a body of soft ductile metal or alloy with
passages therethrough enclosing insulated conducting wires such wires being
arranged in pairs of rows, the two rows composing a pair being in closer proximity
than successive pairs and the adjacent wires taken across the two rows of a pair,
being in closer proximity than adjacent wires taken in the same row, substantially
as set forth..
Sixth. An electric cable having a body of soft ductile metal or alloy with
passages therethrough enclosing insulated conducting wires such wires being
arranged in pairs of rows the two rows composing a pair being in closer proximity
than successive pairs and the wires in one row of each pair alternating in order of
position with those of the other row of the pair substantially as set forth.
Seventh. An electric cable having a body A of soft ductile metal or alloy, with
passages a therethrough enclosing insulated conducting wires ce such wires being
arranged in pairs of parallel rows, the two rows of a pair being in closer proximity
than the adjacent rows of successive pairs, the wires c in one row of a pair
alternating in order of positions with the wires e of the companion row of the pair
and the wires in the adjacent rows of successive pairs having the same order of,
succession and occurrence, substantially as set forth.
Eighth. An electric cable having a body of soft ductile métal or alloy with
passages therethrough enclosing insulated conducting wires such wires being
arranged in pairs of rows the two rows of a pair being in closer proximity than
successive pairs the individual wires in the two rows of a pair alternating in
order of succession and the adjacent wires taken in different rows of a pair, being
in closer proximity than adjacent wires taken in the same row substantially as set
forth.
Ninth. A mandrel A for cable press having at its point a series of nipples e e¹
arranged in one or more pairs of rows, the nipples in one row of such pair or pairs
alternating in order of succession with the nipples in the other or companion row
of the pair, substantially as set forth.
Tenth. A mandrel A having its nipples e e arranged in one or more pairs of
rows, the successive nipples in each row being separated at a greater distance than
adjacent nipples in a pair taken across the rows, substantially as set forth. .
Eleventh. A mandrel A for a cable press having thereon tubular nipples e e¹
arranged in pairs of rows, the two rows of a pair being in closer proximity than
the adjacent rows of successive pairs substantially as set forth.
Twelfth. A mandrel for a cable press having nipples thereon arranged in pairs
of rows. the nipples in the two rows composing a pair alternating in order of
succession and the nipples in adjacent rows of successive pairs corresponding to
each other in order of position substantially as set forth.
Thirteenth. A mandrel for a cable press having nipples e e¹ thereon such nipples
being arranged in pairs of rows with the nipples in the two rows of a pair
alternating in order of succession and the two rows of a pair being in closer
proximity than the adjacent rows of successive pairs substantially as set forth.
Fourteenth. A mandrel A for a, cable press having groups of tubular nipples
thereon which grooves or channels c crossing the mandrel between groups such
grooves or channels being of greater depth than the nipples substantially as set
forth.
Fifteenth. A mandrel A having nipples e. e¹ thereon arranged in pairs of rows
with channels c of greater depth than the nipples formed in the mandrel body
between pairs of rows substantially as set forth.

page_text: Sixteenth. A mandrel A having separate wire passages a¹ therethrough such
passages emerging at the point in two or more distinct groups with grooves or
channels, c formed in the body of the mandrel across the point between groups of
wire passages substantially as set forth.
fe.
Seventeenth: A mandrel for a cable press having separate wire passages there-
through and a chamber récess therein at the point into which the passages open
substantially as set forth.
-
Eighteenth A mandrel for a cable press having wire passages therethrough
with a fim extension at the point surrounding the ends of the passages and
openings in the sides of the rim to admit lead to the rim enclosure substantially as
set forth:
L . C.
Nineteenth. The mandrel A having separate passages a therethrough opening
into a chambered recess C in the point such recess having openings c'in its side
walls for admitting lead supply to recess substantially as set forth.
Twentieth. The mandrel A having separate passages a there through opening
into a chambered recess C: at the point such passages being arranged in one or
more rows substantially as set forth.
+
Twenty first. A mandrel for a cable press having a chambered recess at the
point into which the wire passages open, in combination with a die co-operative
with the walls of the recess in shaping the exterior of the cable substantially as set
forth,
Twenty second: The mandrel A having recess C and rim extensions o in
combination with die E having recesses e therein adapted to receive the
extensions c substantially as and for the purposes set forth.
Dated this 4th day of March 1884