Improvements in the Method of Fixing and Suspending Bare Electric Conductors.
Year: 1898

page_text: Date of Application, 3rd Jan., 1898
Complete Specification Left, 3rd Oct., 1898-Accepted, 22nd Oct.,
1898
Improvements in the Method of Fixing and Suspending Bare Electric
Conductors.
We, ALEXANDER BEWICKE BLACKBURN, Manager of the Electric Construction
Company Limited, of Wolverhampton, and NEWTON HALL WHITE, of The Old
Priory, Sydenham, Kent, Engineer, do hereby declare the nature of this inven-
tion to be as follows:-
In
This invention has for its object to provide an improved method of fixing and
suspending bare electric conductors, including trolley wires such as are em-
ployed with electric tramways for conveying the electric supply to the cars.
systems employing bare conductors suspended overhead from brackets attached
to poles, or other supports, the continued oscillation of the wire by the wind, or,
in the case of tramways, by the repeated passage of the current collector of the
cars along the conductor, gradually weakens the points of suspension, or points
where junction is made with other wires, ultimately producing fracture, and
the free ends of the bare conductor, falling to the ground, may or may not com-
plete the electric circuit, and in any such case, the hanging live conductor is a
source of danger. In order to obviate this danger, we employ the means herein-
after described of suspending the bare conductors, whereby, in the event of the
conductor fracturing, each end of the section fractured is automatically placed
in connection with the opposite pole of the electric supply, and is effectively
earthed, causing the fuses, or other protective devices used in those sections,
to open circuit and cut off the electric supply, thus removing any source of danger
on this account. Taking the bare trolley wires, suspended in the way customary
in tramway work, as an example, one of the arrangements according to this
invention consists in placing at every point of suspension an inverted pair of
metal horns, which are connected with the earth and earth return, generally
through the medium of the pole and bracket supporting the trolley wire. It is
usual to suspend the trolley wire from the bracket arm poles by means of a long
ear, soldered, or mechanically attached, to the trolley wire, and fixed to an in-
sulating bell, which is suspended from the bracket of the pole and hinged to
rock in the same plane as the trolley wire. In our arrangement the earthed
metal horns, above referred to, are so disposed, in relation to these cars, that
when the bare conductor fractures in any place, the weight of the free end, or
the strain on the unbroken portion of the conductor, will cause the ear and in-
sulating bell to rock, or tilt, until one, or other, extremity of the ear, or a portion
of the insulated conductor adjacent thereto, will be brought into contact with one,
or other, of the earthed metal horns. In order to facilitate this, snugs, or pro-
jections, may be fixed above, and at each of the ends, of the trolley ear, and so
disposed in relation to the aforesaid earthed pair of metal horns, that when the
bare conductor fractures in any place the weight of the free end, or section, of
wire behind it, will cause the ear and insulating bell to rock, or tilt, until one,
or other, of the snuga upon the ear will come in contact with one, or other, of

page_text: the earthed metal horns. As the ear is in direct metallic connection with the
live conductor, it will be immediately connected to earth. The rush of current
ensuing will blow the fuse, or other safety device, controlling this section of
the trolley wire, leaving the wire dead and perfectly harmless."
Another method is to attach to the trolley wire, by metallic connection a
short distance apart on each side of the usual suspended insulator, anchor ears,
which are connected by a guy wire to a special insulator, supported vertically
above the usual insulated suspender and ear upon the bracket supporting the
trolley wire. Underneath this insulator, and within the triangle formed by the
guy wires and trolley wire, are metal horns, connected to the earth and rail
return. Normally, these horns are clear of the guy wirus, which cannot
approach, or make contact therewith, when the trolley wire is in working order.
In the event of a fracture, the falling free end of the trolley wire, or the Bag of
the section behind, will cause the guy wires, connected with the live trolley wire,
to come into contact with the metal horns referred to, producing a short circuit,
causing the section fuses, or other protective devices, to cut out, and leave the
trolley wire at earth potential. The guy wires are preferably reinforced at those
points where contact is made with the horn to prevent possibility of fusion and
fracture in advance of the section fuses, or safety cut-outs.
A third method consists in attaching to the trolley wire, or bare conductor,
at the point of suspension, a conducting loop. This loop is in metallic connec
tion with the trolley wire, or bare conductor, and is led over and above the usual
insulated suspender and supporting bracket urn and clear of the same.
'The
jointings of this loop to the trolley wire, or bare conductor, are made a short
distance on either side of the said insulated suspender. When the bracket arm,
pole, or other support, for this insulated suspender, does not serve as a connec-
tion to earth, it is then necessary to fix an earth plate between the highest part
of the loop and the trolley wire, or bare conductor. Normally, the earth plate is
a little below the high part of the loop. In the event of the bare conductor
fracturing, the loop is bent and pulled downwards by the weight of its free end,
thereby making contact between the bare conductor and the earth connection
provided.
Daded
1 day of 1
1000
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C.,
Agents for the Applicanty.
Improvements in the Method of Fixing and Suspending Bare Electric
Conductors.
We, ALEXANDER BEWICKE BLACKBURN, Manager of the Electric Construction
Company Limited, of Wolverhampton, and NEWTON HALL WHITE, of The Old
Priory, Sydenham, Kent, Engineer, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly des-
cribed and ascertained in and by the following statement:-
This invention has for its object to provide an improved method of fixing and
suspending bare electric conductors in connection with electric tramways in-
cluding trolley wires such as are employed for conveying the electric supply
to the cars. In systems employing bare conductors suspended overhead from
brackets attached to poles, or other supports, the continued oscillation of the
wire by the wind, or by the repeated passage of the current collector of the cars
along the conductor, gradually weakens the points of suspension, or points where

page_text: junction is made with other wires, ultimately producing fracture, and the free
end of the bare conductor falling to the ground may, or may not, complete the
electric circuit and in such case the hanging live conductor is a source of danger.
In order to obviate this danger we employ the means hereinafter described of
suspending the bare conductors, whereby, in the event of the conductor fracturing,
each end of the section fractured, is automatically placed in connection with the
opposite pole of the electric supply and is effectively earthed, causing the fuses,
or other protective devices, used in those sections, to open circuit and cut off the
electric supply, thus removing any source of danger on this account. Taking
the bare trolley wires, suspended in the way customary in tramway work, as an
example, one of the arrangements according to this invention consists in placing
at every point of suspension au inverted pair of metal horns, which are connected
with the earth and earth return, generally through the medium of the pole Bud
bracket supporting the trolley wire. It is usual to suspend the trolley wire
from the bracket-arm poles by means of a long ear. soldered, or mechanically
attached, to the trolley wire, and fixed to an insulating bell, which is suspended
from the bracket of the pole and hinged to rock in the same plane as the trolley
wire. In the arrangement according to this invention the earthed metal horns,
above referred to, are so disposed. in relation to these ears, that when the bare
conductor fractures in any place the weight of the free end, or the strain on the
unbroken portion of the conductor, will cause the car and insulating bell to rock,
or tilt, until oue, or other, extremity of the ear, or a portion of the insulated
conductor adjacent thereto, will be brought into contact with one, or other, of the
earthed metal horns. In order to facilitate this, suugs, or projections may be
fixed above, and at each of the ends, of the trolley ear, and so disposed in relation
to the aforesaid earthed pair of metal horns, that when the bare conductor
fractures in any place the weight of the free end, or section of wire behind it,
will cause the ear and insulating bell to rock, or tilt, until one, or other of the
suugs upon the ear will come in contact with one, or other of the earthed metal
horns. As the ear is in direct metallic connection with the live conductor, it
will be immediately connected to earth. The rush of current ensuing will blow
the fuse, or other safety device, controlling this section of the trolley wire, leaving
the wire dead, and perfectly harmless.
Another method is to attach to the trolley wire in electrical connection there-
with and a short distance apart on each side of the usual suspended insulator,
anchor ears, which are connected by a guy wire to a special insulator, supported
vertically above the usual insulated suspender and ear upon the bracket sup-
porting the trolley wire. Underneath this insulator, and within the triangle
formed by the guy wires and trolley wire, are metal horns connected to the earth
and rail return. Normally, these horns are clear of the guy wires, which can-
not approach, or make contact therewith, when the trolley wire is in working
order. In the event of a fracture, the falling free end of the trolley wire, or the
sag of the adjacent unbroken section will cause the guy wires, connected with
the live trolley wire, to come into contact with the metal horns referred to, pro-
ducing a short circuit, causing the section fuses, or other protective devices, to
cut out and leave the trolley wire at earth potential. The guy wires are pre-
ferably reinforced at those points where contact is made with the horn to prevent
possibility of fusion and fracture in advance of the section fuses, or safely cut-
outs.
A third method consists in attaching to the trolley wire, or bare conductor,
at the point of suspension, a conducting loop; this loop is in metallic connection
with the trolley wire, or bare conductor, and is led over and above the usual
insulated suspender and supporting bracket arm and clear of the same. The
jcintings of this loop to the trolley wire, or bare conductor, are made short
distance on either side of the said insulated susponder. When the bracket arm,
pole, or other support, for this insulated suspender, does not serve as a connection
to earth, it is then necessary to fix an earth-plate between the highest part of

page_text: the loop and the trolley wire, or bare conductor. Normally the earth-plate is a little
below the high part of the loop. In the event of the bare conductor fracturing,
the loop is bent and pulled downwards by the weight at its free end, thereby
making contact between the bare conductor and the rail connection provided.
The accompanying drawings represent the devices herein before described.
Figures 1 and 2 illustrate the earthing device applied to the trolley wire clip.
Figures 3 and 4 illustrate the earthing device applied to guy wires connected
with the trolley wire.
Figures 5 and 6 illustrate the loop method of earthing.
Figures 2, 4 and 6 illustrate the position that may be assumed when earth con-
tact is made through the fracture of the wire.
In Figure 1, D represents the source of the electric supply connected at the one
pole through a fuse, F, to the trolley wire, T, and at the other pole to the return
circuit, or rails, R, through which connection is established with the earth. The
trolley wire is suspended, in the usual way by means of the clip, C, and the insu-
lating bell, B, hinged at A to rock in the vertical plane through the trolley wire.
P is the earthed support for the trolley wire and insulator. Horns, H1
and H2, are in metallic connection with the said earthed support, and the
suugs, S1 and S2, are fixed to the trolley wire clip, C, in suitable relation to HI
and H2, so that on the trolley wire breaking, on either side, direct connection
is made between the horn H1, and the snug $ 1, or between the horn H2 and
the snug 82, as shewn in the one case in Figure 2, thereby making an effective
earth connection to the trolley wire, T.
In Figure 3, similar letters refer to parts having similar functions to those
shown in Figure 1. A1 and A2 are anchor ears attached to the trolley wire.
G1 and G2 are guy wires running therefrom to an insulator, I; attached to a
bracket carried above the earthed support P, for the trolley wire. In connection
with the said support P, are horns, H1 and H2, so formed and placed in relation
to the guy-wires G1 and G2 that, normally, they are quite clear and cannot
establish electric contact. In the event of the trolley wire fracturing, contact
will be made at either g' or g³, as illustrated for example in Figure 4.
In Figure 5 similar letters refer to parts having similar functions to those shewn
in Figures 1 and 3, J 1 and J2 are the ends of a conducting loop, J, joined to
the trolley wire, T, passing over and above the support, or bracket arm, P. H is
an earth-plate situated under the conducting loop, but clear of it. We may attach
to the plate H insulated guides K K to prevent accidental contact between
the said plate and the loop J. In the event of the trolley wire fracturing, the
loop, J, is dragged down into connection with the earth-plate, H, as shown in
Figure 6.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
wo claim is: :-
1. In combination with the trolley wire of an electric tramway, an earthing
horn, plate, or contact making device, (so constructed as not to interfere with the
free working of the under-running trolley), whereby the trolley wire circuit is
connected to the return and earth circuit automatically by the broken, or falling,
trolley wire substantially as hereinbefore described.
2. The general arrangements and combinations of parts, substantially as, and
for the purpose, herein before described, and illustrated in the accompanying
drawings.
" 1
Anal 100Q
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.