Improvements in Protecting, and in Fittings for Connecting, Lead Covered or other Armoured Electric Cables with Naked or other Conductors.
Year: 1894

page_text: Date of Application, 28th June, 1894
Complete Specification Left, 29th Apr., 1895-Accepted, 15th June, 1895
PROVISIONAL SPECIFICATION.
Improvements in Protecting, and in Fittings for Connecting, Lead
Covered or other Armoured Electric Cables with Naked or other
Conductors.
I, GEORGE HINDE NISBETT of "Ashfield," Huyton, near Liverpool, in the
County of Lancaster, Electrical Engineer, do hereby declare the nature of this
invention to be as follows:-
This invention has for its object an arrangement whereby an armoured cable,
more especially a lead covered one, can be connected with terminals or with other
cables in such a manner that the dielectric surrounding the conductor shall be
protected from moisture or other atmospheric influences.
In carrying the invention into effect, the cable may be covered with lead or other
armour and a gland provided, preferably formed of solder. It can, however, be
formed of lead or other metal or material capable of being firmly jointed to the
lead covering of the cable by means of solder. The cable enters the interior
chamber of a cast iron box. In this chamber also the gland is screwed with red
lead or other material so as to make a thoroughly impervious joint. Two clamps
are clamped respectively on to the outer and inner condutor, which are bared for
the purpose. Terminals attached to these clamps are brought up through a slab of
glass, marble, or other insulating material covering the top of the chamber, and to
these terminals a fuse is screwed by screws, similar screws connecting the other
end of the fuse with other terminals. The screws of these latter terminals pass
down and firmly clamp the conductor against the terminal. This conductor can
be carried away in any convenient manner through the side of the box, either as a
covered conductor or naked. The gland, if made of solder, is now firmly fused
to the lead covering, if it be made of a hard and comparatively infusible metal, it is
soldered to the lead pipe instead.
When the cable is fixed in the manner set forth,
a small screw stopper is unscrewed from the side of chamber and this chamber is
filled through the orifice with melted insulating material; the screw is then
attached. It is obvious that, where it is desired to connect two or more armoured
cables in a box in this manner, the required number of compartments should be
used and each can be brought into its respective compartment or into one
compartment and protected therein in precisely the same manner in which the
one cable already shown is arranged. In some cases, however, it is impracticable or
undesirable to use a solder gland in this way. In place of this, a device is adopted,
in which the gland is made of any convenient metal placed round the cable and
screwed into a box. A stuffing box or gland is screwed onto the gland and a ring
of lead or other soft metal, or a coil of soft metal wire, is placed round the cable.
The gland is now firmly screwed up on to the other gland until the ring of metal is
squeezed out of form and fills up the annular V-shaped space between the two
glands, thus preventing all admission of air to the box. In some cases, the naked
end of a sheathed conductor has to be connected to a terminal or other conductor
likewise naked in this case, a box such as already described is not required but
still the dielectric has to be protected from the air. In this arrangement I cut
back the lead for a sufficient distance regulated by the amount of free or naked
conductor which is required. I then strip off a portion of the insulation so as to
leave the requisite naked conductor beyond to within one half or three inches
(dependent upon the potential upon which the conductor is to work) from the end
of the lead. I then solder securely to the bare conductor a short distance from the

page_text: end of the insulation a screwed brass washer, having previously slipped over the
cable a solder ferrule and an ebonite or other insulating box or tube. Having
soldered the washer securely to the conductor, I bring up the insulating tube which
is screwed at both ends, the one end to engage the brass washer and the other to
receive the ferrule. I then, through a hole in tube or at the open end, fill the space
between the ebonite insulating tube and the dielectric of the cable with a suitable
insulating compound in the melted state, I then bring up the before mentioned
ferrule and screw it onto or into the ebonite; the compound, being still in the fused
condition, works into the respective threads and makes the whole thorough.y
watertight. Having the ferrule in place, I can now solder it if desirable to the
lead covering of the cable which has previously been cleaned at that part for the
purpose. The ferrule may as before stated be brass, copper, lead, solder or other
metal. I prefer however to use solder, as the heat required to connect it to the
lead covering of the cable is not so great as in the other cases, and therefore, the
ebonite is not so likely to be damaged. The free end of the cable can be left of
any length and then have attached to it a shoe for clamping under a bolt head, or
it may be taken into an ordinary screw down terminal on a switch board, or used
for other purposes.
In this way I provide a fitting which prevents absorption of
water by the dielectric of the cable at an open end. In another variation of this
device and another form of washer, the gland enters the ebonite tube instead of
being screwed over it. Further, the sheath is screwed to the ferrule, then the
parts filled to overflowing with liquid insulator, the gland is then pressed forward
towards the soldered insulator and the screwing up of the gland compresses the
liquid insulator, thus firmly closing all admission of air.
Dated this 27th day of June 1894.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
Improvements in Protecting, and in Fittings for Connecting, Lead
Covered or other Armoured Electric Cables with Naked or other
Conductors.
I, GEORGE HINDE NISBETT of "Ashfield" Huyton near Liverpool in the
County of Lancaster, Electrical Engincer, 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. :-
This invention has for its object an arrangement whereby an armoured cable,
more especially a lead covered one, can be connected with terminals or with
other cables in such a manner that the dielectric surrounding the conductor
shall be protected from moisture or other atmospheric influences at that point.
The invention is best described by aid of the accompanying drawings, in which,
Figure is a vertical section; and
Figure 2 a sectional plan of a box for connecting a double concentric cable with
two naked or other conductors; and for providing fuses in each conductor.
Figures 3 and 4 vertical section and plan of the device for connecting a triple
concentric cable with three conductors in the same way.
Figures 5 and 6 are two end views, section through the cable; and
Figure 7 a vertical section of the device for enabling the cable to enter such a
box as set forth in Figures 1 and 2 or any other form of box without the use of
solder or lead :
Figure 8 is an end view and
Figure 9 a section of another simpler form of a device for connecting single

page_text: caoles in which the conductor of a cable end is bared for connection with a
terminal without the air or moisture being able to get to the dielectric ;
Figures 10 and 11 end views; and
Figure 12 a section of a similar device for connecting concentric cables to
terminals or other cables;
Figure 13 a slight modification.
Referring now first to Figures 1 and 2-
In these, A is a cable covered with lead or other armour; B, a gland preferably
formed of solder. It can, however, be formed of lead or other metal or material
capable of being firmly jointed to the lead covering of the cable by means of solder.
C is a box of metal or of wood, ebonite or other insulating material having a
cover c of glass or metal and an interior chamber C¹ into which the cable enters and
into which gland B is screwed with red lead or other material so as to make a
thoroughly impervious joint. D and E are two metal clamps, clamped respectively
on to the outer and inner conductor, which are bared for the purpose. F and F' are
terminals attached to these clamps. G and G'are other terminals. The terminals F F¹
are brought up through a slab Hof glass, marble, or other insulating material covering
the top of the chamber C¹ and to these terininals the fuses.I are screwed by
screws J J; similar screws J and J³ connect the other ends of the fuses with other
terminals G and G. The screws of terminals G G¹ pass down and firmly clamp
the conductor K against the terminal G. This conductor can be carried away in
any convenient manner through the side of the box as set forth at L, either as a
covered conductor as shown, or naked. The gland B, if made of solder, is now
firmly fused to the lead covering A; if it be made of a hard and comparatively
infusible metal, it is soldered to the lead pipe instead. When the cable is fixed in
the manner set forth, a small screw stopper M is unscrewed from the side of
chamber C and this chamber is filled through the orifice with melted insulating
material such as parafine wax, ozokerite, or other compound which is fluid when
heated and more or less solid when at ordinary temperature; the screw is then
attached, and thus the possibility of moisture or dampness getting to the end of the
dielectric is prevented. It is obvious that where it is desired to connect two or
more armoured cables either single conductor or concentric in a box in this manner,
the required number of compartments C should be used and each can be brought
into its respective compartment or into one compartment and protected therein in
precisely the same manner in which the one cable already shown is arranged.
My method of connecting a triple concentric cable with three conductors is on
precisely the same lines as already described. It is shown in Figures 3 and 4,
those parts which correspond with the arrangements depicted in the two preceding
figures, being denoted by the same reference letters. A is the triple concentric
cable, D, E and E¹ the clamps clamped to the respective conductors, which are
bared for the purpose, and F F1 and F2 are the terminals attached to these clamps.
G, G and G2 are the other terminals. Mare holes for the conductors,
corresponding to the conductors K in Figures 1 and 2, which are clamped to the
terminals G G and G2. To these terminals fuse wires or strips are screwed by
screws J, J and J5, while similar screws J J and J2 connect respectively the
other ends of the fuses with the other terminals F F' and F.
In some cases, it is impracticable or undesirable to use a solder gland in the ways
above described. In place of this the device set forth in Figures 5, 6 and 7 may
be adopted. In these A is the cable as before, B is a gland made of any convenient
metal placed round the cable and screwed at 6 into a box such as C³ set forth in
Figures 1, 2, 3 and 4. N is a stuffing box or gland screwed onto gland B, and O a
ring of lead or other soft metal, or a coil of soft metal wire or other suitable packing
material placed round A. Gland N is now firmly screwed up on to gland B until
the metal is squeezed out of form and fills up the annular Vshaped space between
glands B and N, thus preventing all admission of air to the box. In some cases,
the naked end of a sheathed and insulated conductor has to be connected to a
terminal or other conductor likewise naked; in this case, a box such as already

page_text: described is not required but still the dielectric has to be protected from the
moisture. Figures 8 and 9 set forth this arrangement. In these, as before, A is
the cable. From this cable I cut back the lead for a sufficient distance regulated
by the amount of free or naked conductor which is required. I then strip off a
portion of the insulation P so as to leave the requisite naked conductor beyond
to within one half to three inches (dependent upon the potential upon which the
conductor is to work) from the end of the lead. I then solder securely to the bare
conductor a short distance from the end of the insulation a screwed brass washer Q
having previously. slipped over the cable a solder ferrule, such as that described
in Figures 1, 2, 3 and 4, B, and an ebonite or other insulating box or tube R.
Having soldered the washer securely to the conductor, I bring up the insulating
tube R of ebonite or other material, which is screwed at both ends, the one
end, to engage the brass washer Q and the other end to receive the ferrule B. I
may then through a hole not shown in tube R, or at the open end fill the space
between the ebonite insulating tube and the dielectric Pof the cable with a
suitable insulating compound such as parafine wax, ozokerite or a mixture having
similar properties in the melted state. 1 then bring up the before mentioned
ferrule and screw it onto or into the ebonite; the compound being still in the fused
condition works into the respective threads and makes the whole thoroughly
watertight. Having the ferrule in place, I can now solder it if desirable to the
lead covering of the cable which has previously been cleaned at that part for the
purpose. The ferrule B may, as before stated, be brass, copper, lead, solder, or
other metal. 1 prefer however to use solder, as the heat required to connect it to
the lead covering of the cable is not so great as in the other cases, and therefore,
the insulator is not so likely to be damaged. The free end of the cable can be left
of any length and then have attached to it a shoe for clamping under a bolt head,
or it may be taken into an ordinary screw down terminal on a switch board, or used
for other purposes.
In this way provide a fitting which prevents absorption of
water by the dielectric of the cable at an open end.
Figures 10, 11 and 12 shew the device when applied to connecting concentric
cables, which is practically on the same lines as the preceding example, A being the
cable, P the dielectric, R tubes, B ferrule or gland and Q the washer. It is obvious
that B might enter the ebonite tube R instead of being screwed over it, it being
immaterial which plan is adopted.
Figure 13 shews a slight modification, in which A. is the cable, P the dielectric,
R tubes, B solder gland, brass, gun metal or copper tube, T hole for soldering.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is-
1. The method of connecting lead or armoured covered electric cables with other
conductors and the providing of a fuse in such manner that the dielectric of the
cable shall not be exposed to the air, which consists in passing the cable into a box
through a gland screwed into the said box, and soldered or otherwise fused or
hermetically connected to the sheathing of the cable, and filling that part of the
box containing the exposed dielectric with an insulating compound, substantially as
described and illustrated.
2. The various fittings or devices combined so as to form an entire joint for
protecting the dielectric of sheathed cable ends, substantially as herein described
and illustrated respectively in Figures 1 and 2, Figures 3 and 4, Figures 5, 6
and 7, Figures 8 and 9 and Figures 10, 11, 12 and 13 respectively.
3. In fittings for connecting lead or armoured covered electric cables with other
conductors the use of a gland formed of solder, substantially as described.
W. P. THOMPSON & Co.,
Of Liverpool, Manchester, Birmingham, and London, Patent Agents.