Improvements in and connected with Conduits, more especially suitable for Electrical Conductors.
Year: 1896

page_text: Date of Application, 1st Aug., 1895-Accepted, 12th Sept., 1896
COMPLETE SPECIFICATION.
[Communicated from abroad by EDWIN TRUMAN GREENFIELD, of No. 44 Broad
Street, New York City, in the County of New York and State of New York,
United States of America, Electrician.]
Improvements in and connected with Conduits, more especially
suitable for Electrical Conductors.
.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, 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:-
My invention relates to improvements in electrical conduits but particularly to
underground or subway conduits, and its objects are:
First, to afford a simple and efficient means for insulating electrical conductors
at manhole crossings in systems of subway or underground conduits; second, to
construct a service box or manhole chamber in sectional parts so as to adapt the
same for any desired number of subway or conduit tubes; third, to afford
general flexibility of interconnection between the ends of subway or conduit tubes
where they enter a manhole or point of distribution by the use of flexible insulating
or protecting tubes; fourth, to provide pairs of subway or conduit tubes with a
perfect insulating joint and means for holding the ends of said tubes firmly
together.
I accomplish these several objects with the means hereinafter described with
reference to the accompanying drawings:-
Figure 1 represents a side elevation, partly in section of a subway or conduit
embracing two tiers of subway or conduit tubes and.my improved form of manhole
chamber with a flexible protecting tubing joining one of said conduit tubes to a
branch leader or circuit located above ground.
Figure 2 represents in plan view a subway or conduit embracing a number of
subway or conduit tubes entering a manhole chamber and provided with my
improved means of effecting flexible interconnecting protecting means for uniting
any pair of such subway or conduit tubes, the top of the manhole chamber and
the cover of the subway being removed for the purpose of illustrating the interior
structure of said parts.
Figure 3 is a transverse section taken on the line x-x Figure 1, and as seen
looking from right to left in the direction of the arrows upon that figure of. the
drawings.
Figure 4 is a plan view of the manhole chamber as seen looking at Figure 3
from the top toward the bottom of the drawings.
Figure 5 is an enlarged longitudinal sectional view of a pair of subway or
conduit tubes provided with my improved insulating joint and means for firmly
uniting the ends thereof together.
Figure 6 is an enlarged end view of one of the tubes and its coupling joint
shown in Figure 5 as seen looking at the ends thereof before said tubes are joined
together.
Referring now to the drawings in detail, and first to Figures 1 to 4 inclusive:-
D represents a wooden trough preferably creosoted or treated in any of the well
known ways to protect it from the action of water, and D' is a wooden cover

page_text: therefor. PP Pi are rows or tiers of subway or conduit tubes made preferably
of paper treated or incorporated in the usual way with insulating material, said
tubes being properly spaced and sustained by wooden spacing strips when they are
laid in the conduit trough D and afterwards surrounded with molten asphalt
or pitch A which is allowed to harden, after which the cover D¹ is secured in
place.
M represents the top or upper portion of a manhole chamber made preferably
of cast iron and of rectangular form in plan, said top portion being strengthened
by radially disposed ribs R2 R2 &c., and T is a removable cover therefor. The
lower surface of this top portion of the manhole chamber is provided with a rim,
bead or extension K which is adapted to fit snugly over the rectangular portion O
of the body of the manhole chamber, which rectangular portion is provided with
a similar bead at its lower surface adapted to fit in a like manner over a
corresponding bead upon another sectional part 01. The bottom sides of the top
portion M and the corresponding top and bottom sides of the portion O are provided
with semi-circular openings F F which, when the parts are placed one upon the other
after the manner shown in Figure 3, constitute the inlets for the conduit or
subway tubes P" P. By thus constructing the manhole chamber of sectional
parts O, I am enabled to build up a manhole to any desired height so as to
accommodate any number of subway or conduit tubes, this feature of extensibility
of a manhole chamber being deemed by me as important, in that it adapts the
invention for ready use in accordance with the demands of the system, wherever
used. The lower or bottom section of the manhole chamber O₁ is provided with
an outlet J for drainage. In the top portion of the manhole chamber I provide
an opening through a projecting portion L for the purpose of enabling one to
convey a branch feeder or main from the subway to a point ahove ground for use
as an electric light post or for any other service usage. When the manhole
chamber is placed in position between the adjacent ends of the subway so that the
openings FF are in alignment with the incoming subway or conduit tubes PI P1,
PP as shown in Figures 1 and 2, I insert short metallic sleeves P P through the
openings F F and around the incoming subway or conduit tubes, said sleeves
being provided with screw-threads on their inner ends. I then provide a
temporary dam around said screw-threaded sleeves at the openings and, pour
liquid asphalt in the conduit box D around the free ends of the pipes P¹ and the
adjacent ends of the metallic sleeves P until the spaces around the tubes and sleeves
are completely filled with said asphalt, thereby rendering an absolutely water-tight
joint between the manhole chamber, the conduit boxes and the contained tubes and
sleeves.
R RR represent expansible soft rubber tubing of sufficient length, when
expanded, to afford cross connection between any pair of subway or conduit tubes
located within the manhole chamber. These tubes R R are secured by wire
wrappings ww at their opposite ends to T-shaped hard rubber thimbles or union
sockets t t. N N are union locking nuts serew-threaded on their inner surfaces
and each provided with a shoulder having a bearing against the flange of its
thimble t, as clearly shown in Figures 1 and 2. When it is desired to connect any
opposite pair of subway or conduit tubes P₁ P, the conductor is drawn there-
through to the manhole chamber and one of the flexible interconnecting tubes R R
is secured to the inner end of said subway tube in the contracted position shown
near the centre of Figure 2. The conductor is drawn forward to the other
conduit tube through which it is to be conveyed and the union nut N is connected
to the screw-thread upon the sleeve which surrounds said subway tube or conduit,
thereby extending the soft rubber tube in the manner shown in the lower portion
of the drawing in Figure 2.
In Figures 1 and 3, I have illustrated means for connecting one of the subway
tubes with a lamp-post or other point of service above ground and surrounding the
conductor running thereto by one of my improved flexible insulating tubes, R',
such tube being provided at its opposite ends with insulating thimbles or union

page_text: sockets and union locking nuts N', one of which is secured to the upper
portion of a locking socket or thimble E provided with insulating linings P' and P,.
the outer end of said flexible tubing being connected by the union nut N to the
end of a tube which is secured to the manhole by two nuts QQ, as clearly shown.
in Figure 3. With such an arrangement of flexible tubing, I am enabled to furnish
cross connections between any two of a series of subway tubes and to afford quick
and easy access to the conductor or conductors surrounded thereby. I am also
enabled to, in a similar manner, insulate with one of my improved flexible cross.
connectors any conductor which runs to a point above ground.
I am aware that it is not new to cross connect subway tubes in manhole-
chambers by rigid telescopic sleeves and I therefore make no claim thereto.
In Figures 5 and 6 I have illustrated, in enlarged views, my improved form of
coupler and insulating joint for conduit tubes. In these two figures of the
drawing P represents a paper or analogous insulating tube surrounded by an
armour P of metal. CC represent cup-shaped locking collars secured to the ends
of said tubes by indenting the same in grooves S S in the inner surfaces of the
collars before the lining tubes P¹ P1 are inserted in position. These cup-shaped
collars C C are provided with lugs or ears for the reception of bolts B B.
FF and GG represent semi-circular openings in the outer faces of the locking
collars C C, the opening F being adapted, when the collars are placed face to face,
to constitute a means for pouring into the cylindrical or annular space between the
collars, a liquid insulating material, such as asphalt, the openings G G being for
venting purposes.
T represents an annulus or ring of prepared paper or other insulating material
adapted to fit snugly over the adjoining ends of the projecting paper or insulating
tubes PP, said adjoining ends projecting, as clearly shown in Figure 1, slightly
beyond the ends of the armoured tubes P P. In using my improved joint the
armoured tubes are placed end to end so that the bolt holes of the locking
collars CC are in alignment and so that the openings F F and G G are located
at the upper or top side when in position.
The annulus or ring T is placed in position over one of the armoured tubes and
said tubes are drawn together into the position shown in Figure 5 by means of the
bolts B B. After they are thus firmly secured, the annular space around the
collar T and the ends of the tubes PP, P P is filled with liquid insulating
material, such as hot asphalt, by pouring the same through the filling opening F,
the openings G G constituting vent openings for the escape of any air confined in
open space between the locking collars.
It will be readily understood that with such an arrangement, not only is the
joint between the abutting ends of the tubes made water-tight, but additional
surety is given thereto by reason of the presence of the hot or molten asphalt
which surrounds the annulus or collar T and the ends of the adjoining tubes and,
which in effect, when cooled, causes said parts to be united together into one
common mass.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is:-
1. In a subway or conduit a series of conduit tubes extending into a manhole
chamber or to a point of distribution, in combination with flexible cross connecting
tubes and with detachable or other means for securing said flexible tubes to any
pair of said conduit tubes, for the purpose specified.
2. A subway or conduit provided with flexible means for joining two or more
conduit tubes and a flexible side or branch tube running therefrom to a service
conduit tube located above ground, substantially as described.
3. A subway consisting of a series of conduit tubes located in a conduit tubo
trough, the ends of said tubes extending into a manhole chamber and being
surrounded by short metallic sleeves and all embedded in asphalt which binds the

page_text: tubes, the sleeves, the conduit trough and the manhole chamber firmly together,
substantially as described with reference to Figures 1 and 2 of the accompanying
drawings.
4. A manhole chamber constructed substantially as described with reference to
Figures 1 to 4 of the accompanying drawings and for the purpose specified.
5. For uniting two or more conduit tubes a pair of collars provided with means
for securely locking them to each other and to the ends of the tubes, said collars
being so constructed as to constitute, when joined, an annular chamber around the
contiguous ends of the tubes, in combination with an insulating aunulus or ring
which surrounds the said ends of the tubes, and a mass of insulating material which
fills the aforesaid annular chamber, substantially as described.
6. A pair of armoured or other conduit tubes connected together at their ends
by means of collars constructed substantially as described with reference to
Figures 5 and 6 of the accompanying drawings and for the purpose specified.
Dated this 1st day of August 1896.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.