AN IMPROVEMENT IN ELECTRIC CABLES AND IN MANDRELS FOR MANUFACTURING THE SAME
Year: 1884

page_text: "
I RICHARD SOLOMON WARING of the City of Pittsburg in the County of
Allegheny, State of Pennsylvania United States of America Electrical Engineer
do hereby declare the nature of my Invention for AN IMPROVEMENT IN 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 in Figures 1 and 2 of the accompanying Drawing in which Figure 1*is
a perspective view of my improved electric cable.
Figure 2 is a transverse sectional view of the same.
This part of my Invention relates to certain improvements in compound electric
cables designed more particularly for use in water and in general terms it consists
of a cable having a solid as distinguished from a tubular body of soft ductile metal
or equivalent alloy such body enclosing insulated conducting wires and also a series
of strengthening wires each within its appropriate passage through the body, the
conducting wires being arranged in close proximity around the solid core of soft
metal and the strengthening wires being arranged in circular order around the
conducting wires as hereinafter more fully described and claimed.
The purpose of my present Invention is to secure a cheap cable by employing a
small quantity of lead and so disposing the same as to utilize it to the best
advantage. I also have in view an improvement in the cable by making its centre
or core solid as distinguished from tubular whereby danger of minute pores or
holes in the lead characteristic of pipe like forms is avoided and air and all other
agencies liable to convey moisture into the interior of a tubular cable are wholly
excluded.
In cables having a tubular body it is extremely difficult to secure such
perfectness both at joints and also throughout the entire length of cable that when
laid in water some moisture will not find its way to the interior and even moist air
baving access to the tubular interior may deposit its moisture on the inner wall
and this moisture from whatever source it may com may in time fin access
through pores or minute holes in the lead body to the insulating material
Price 1
r

page_text: surrounding a wire or wires. The requisite elements are thus supplied to excite or
.produce electric or electrolytic action between the lead and copper usually
employed in this class of cables for conductors and such action though weak
is very detrimental to good working of the cable. In order to prevent these and
other like evils in the class of cables referred to I make my improved cable as
follows-
A body A is formed of lead or other equivalent soft ductile metal or alloy
adapted to make adhesive union when subjected to pressure within a lead press..
The form and size in cross section of this body is determined by the die opening
of the press. I prefer a smooth rounded form as shown but this may be varied as
desired without departing from my Invention. Within this body of soft metal are
enclosed a number of insulated conducting wires c each in its appropriate or
separate passage a made longitudinally through the body. These wires care
placed in close proximity around the solid core or centre a² of the soft metal body
the inner walls of covering between such wires being comparatively thin but
continuous or unbroken thereby affording complete metallic separation of the wires
for the purpose of preventing electrical induction.
It has been found by experience that comparatively light walls will afford the
desired protection in this respect and therefore that the wire may be brought into.
close proximity so as to be covered through the inner spaces between wires with a
comparatively small quantity of lead.
Difficulty has been experienced however in securing the requisite flow and
pressure of lead into the spaces between wires especially when, as in the present*
cable the conducting wires are surrounded by another or outer series of wires.
To overcome or lessen this difficulty I prefer to include three conducting wires c
in the cable body and place them in triangular arrangement about the centre a². so
that comparatively wide openings may be afforded between any two of the wires
for entrance of lead between them, though the space to be filled within the circle
of wires is very small. With three wires arranged as shown a minimum of inner
or central space is afforded with a relatively wide passage or approach between
wires to such space. This arrangement of the three wires has advantage therefore
not only in facilitating the formation of a solid core and continuous unbroken
inner walls of covering but also in including the wires in comparatively small
space and covering them with a minimum quantity of lead.
In order to protect the wires from exterior injury the greater part of the metal
of the covering is disposed around the exterior of the conducting wires. This
cable is designed however more particularly for laying in water where it may be
subject to rubbing movement on stones or gravel and exposed to abrasion by
floating substances like ice, drift, boats &c.
In order to prevent injurious wearing away of the exterior or lead covering and
also to give the cable greater tensile strength so that it may sustain its own weight
if suspended some distance over a rough bed or in air hard metal wires e² are
'enclosed in separate passages in the lead body, such wires being by preference
double the number of conducting wires and arranged in circular order around the
conducting wires and occurring on either side of the radial lines produced through
the latter wires. This order of occurrence is given with reference to introducing a
flow or supply of lead from the exterior between each two of the outer wires e²
and directing such flow upon or against the inner wires c as at s Figure 2 and also
into the spaces between wires as at By these features of construction and
arrangement I am enabled to include the three conducting wires and the
surrounding series of strengthening and protecting wires e² within a cable having
but a trifle larger area in cross section and employing but little more lead than is
ordinarily employed for a single wire. This is of material advantage not only in
point of economy but also in combining lightness and strength with an increased
number of conductors thereby adapting it especially to the peculiar requirements
of cables laid in water or suspended in air. Also by making the enveloping
body of metal solid at the centre as distinguished from túbular greater security is

page_text: afforded against entrance of moisture and also a more compact and convenient form
and construction of cable is secured.
The second part of my Invention relates to mandrels for manufacturing lead
armored electric cables. and is illustrated in Figures 3 to 7 of the accompanying
Drawing in which Figure 3 is a view in side elevation of my improved mandrel.
Figure 4 is an end view looking down upon the nipples or point.
Figure 5 is a longitudinal sectional view the plane of section being indicated by
the line XX Figure 4.
Figures 6 and 7 are transverse sectional views taken in the planes of the
lines Y Y and Z Z respectively.
This part of my Invention relates to the manufacture of an electric cable such
as represented at Figures 1 and 2 having a group of insulated conducting wires
enclosed each in its appropriate passage formed in the common body of lead
or equivalent soft metal covering which covering also encloses a series of hard
metal wires designed to afford tensile strength and prevent injury to the conducting
wires by abrasion or wearing away of the lead covering.
The only material difficulty encountered in the manufacture of a cable of this
construction by means heretofore employed, namely a lead-press, is due principally
to lack of provision therein for supplying lead to the inner spaces between wires
and at the same time secure the desired proximity of wires and prevent latéral
displacement of them by pressure of lead thereon.
My present Invention is especially designed to meet these and similar
requirements in manufacture and in general terms it consists of a mandrel having
passages therethrough both for the insulated conducting wires and also for the
strengthening wires, such passages terminating at the point of the mandrel in
tubular nipples, the nipples for strengthening wires being arranged at intervals
around the nipples for conducting wires, with grooves in the outer surface of the
mandrel for directing flow of lead to different parts of the spaces surrounding the
nipples, as hereinafter more fully described and claimed.
In the Drawing A represents a tapering body of iron steel or other suitable.
metal having a threaded socket a in its base end adapted to screw on to the
threaded end of tubular core bar B. A chambered recess A¹ in or below the base
of the socket registers with the tubular passage of the core bar and affords
a common opening for leading in the several wires to be contained in the cable.,
From the base of recess A¹ are drilled separate passages a¹ leading through the
body A and emerging at the point or tapered end in the form of distinct nipples
or tubular extensions e e¹. The inner or central nipples e (three being shown in
the present instance) are designed for passing therethrough the insulated conducting
wires and they occupy positions in close proximity at equal intervals from the
common centre. The outer or surrounding nipples e¹ (six in number as shown) are
made at equal intervals around the inner set of nipples e and are designed for
passing therethrough the strengthening wires of the cable.
These nipples may be made integral with the body portion of the mandrel by
turning or otherwise forming them thereon, or if preferred, they may be made
separate from and be screwed into tapped holes in the end of the body portion
or be otherwise rigidly secured thereto. I prefer, to make them on or as integral
parts of the body because they can be formed in this way of less metal and within
less space.
In order to make provision for passing a supply of lead into the inner spaces.
between nipples grooves care cut longitudinally in the tapered sides of the
mandrel which extend downward to the point between the nipples e¹. In depth
these grooves extend within the circle of nipples e¹ and by preference to or within
the circle of inner nipples e. It will be observed that the number of grooves c and
of nipples e¹ is double the number of nipples e and that the nipples e¹ occur at
equal intervals on either side of radial lines produced from the nipples e. This
provision is made with reference to directing streams of lead through the grooves c
both upon the extreme outer surface of nipples e and also upon their adjacent sides

page_text: through grooves directed to or into the spaces between nipples e.
Lead directed.
in this manner will pass readily into the narrow central spaces between nipples e
and will ensure adhesive union with the lead directed upon the outer sides of
three nipples and thus passing off from the nipple points will envelope the
insulated wires with continuous unbroken walls of lead covering which however
will be thin or light between wires.
'
Substantially the same uniformity of lead supply is thus afforded within and
around the central portion of the cable as though the nipples e¹ and the
.strengthening wires were not present and in doing this I avoid injurious side
pressure of lead upon the outer nipples e¹ and. also upon the wires passed
therethrough. This is an important feature of construction as it enables me to
make the nipples comparatively light so as to secure compactness without injurious.
weakening of them.
It will also be observed that lead following the depths of grooves c will have
motion or direction of flow substantially in the longitudinal direction of the nipples
making but comparatively little lateral spread necessary to unite the lead around
the nipples when the same are reached. This is also a material advantage in
preventing breakage of nipples by side pressure thereon and it affords almost
complete relief from side pressure not only upon the strengthening wires as above
explained but also upon the insulated conducting wires. Side pressure if it existed
would be a fatal obstacle to close grouping of wires owing to the tendency of such
pressure to flex or bend the wires out of their true or desired relationship or
positions and the construction and arrangement of grooves and nipples by which
such difficulty is obviated is an important feature of advantage and improvement
with reference to close grouping of wires.to secure economy in the use of lead and
lightness of product.
In illustrating the principles of my Invention I have shown provision for three
conducting wires six strengthening wires and a corresponding number of grooves.
1 do not wish however to limit my Invention to these or any specific numbers.
as the same may be increased or diminished as required with reference to the
desired size or capacity of cable. But in making such changes in the number
of wires, I prefer to retain substantially the same relationships of numbers and
positions of nipples and grooves, because better results are secured thereby in
covering the wires.
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,
"
1.. An electric cable having a solid body of soft ductile metal or equivalent alloy
enclosing insulated conducting wires each in its appropriate passage through the
body such wires being arranged in close proximity around the solid core or centre
of the body with a series of strengthening wires enclosed within the soft metal
body such strengthening wires being arranged in circular order around the
conducting wires substantially as set forth.
2. An electric cable having a solid body of soft ductile metal or equivalent alloy
enclosing three insulated conducting wires each in its appropriate passage through
the body such wires being arranged in close proximity at intervals around the
solid core or centre of the body with a series of strengthening wires enclosed
.within the soft metal body, such strengthening wires being arranged at intervals
around the conducting wires substantially as set forth.
3. An electric cable having a body A. of soft ductile metal or alloy enclosing
three insulated conducting wires c each in its appropriate passage through the
body, such wires being placed in triangular relationship and in close proximity
around the solid metal centre a2 with a series of strengthening wires e enclosed in
the body of soft metal such strengthening wires being double the number of
conducting wires c and arranged round the latter wires on either side of radial
lines produced through the conducting wires substantially as set forth,

page_text: 4. A mandrel for a cable press having separate passages therethrough for
insulated conducting and for strengthening wires such passages terminating at
the point in tubular nipples the nipples for conducting wires being grouped at -the
centre and the nipples for strengthening wires surrounding such central.group
with grooves in the surface of the mandrel extending to the point between the
nipples for strengthening wires substantially as set forth.
5. The mandrel A having wire passages therethrough terminating at the point
in separate nipples, three of such nipples e being near the centre and surrounded
by double the number of nipples e arranged in circular order with grooves cin
the surface of the mandrel extending in depth between the outer nipples e¹
to the inner group of nipples e substantially as and for the purposes set forth:
n
th 1
C