Improvements in Electric Railway Conduits with Tubular Conductors.
Year: 1890

page_text: Date of Application (in the United Kingdom), 24th Sept., 1890
Complete Specification Left, 24th Sept., 1890-Accepted, 20th Dec., 1890
COMPLETE SPECIFICATION.
Improvements in Electric Railway Conduits with Tubular
Conductors.
I, CHARLES JOSEPH VAN DEPOELE, residing at No. 502 Essex Street, in the
City of Lynn, County of Essex and State of Massachusetts, one of the United
States of America, Electrician, 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 electric railways and more particularly
to an improved conduit for sub-surface conductors, the particular object of the
invention being a conduit within which a main supply conductor or conductors
can be completely enclosed and effectually protected from any and all exterior
influences. With this object in view I form each main supply conductor as a
continuous metallic tube, which may be of any desirable metal although the
cheapest forms, such as wrought iron gas pipe, will answer for this purpose. The
tubular conductor is to be well insulated upon its outside as by a coating of a
heavy bituminous substance having high insulating properties, together with a
strong fabric.
The tubular conductor is carried upon insulating supports within the best
known form of slotted sub-surface conduit, the conductor being then doubly
protected.
The current is collected from the interior surface of the tubular conductor.
This is accomplished by contact-making devices in the form of metallic plungers
carried by insulating sockets detachably secured in the conductor and readily
removable for replacement or examination. The contacts are separately con-
structed and each is provided with a small retracting spring contained within
its casing and they are all arranged to be entirely independent and self-acting.
The current is collected by means of a long shoe which is carried by a thin shank
extending through the surface slot and into mechanical as well as electrical
connection with the vehicle, and the shoe is desirably arranged to engage and
press down a plurality of contacts simultaneously that is to say, as one of the
contacts is released by the passage of the shoe, one in advance is pressed down, and
two or more are always under pressure and in contact with the conductor. With
this arrangement the failure of a few of the contacts would make very little difference
and would not be sufficient to interfere with the operation of the line.
The details of construction of a form of my apparatus are shown by way of
illustration.
Fig. 1 is a transverse end view partly in section showing a double conductor
conduit embodying the invention.
Fig. 2 is a similar view showing a conduit provided with a single conductor.
Fig. 3 is a longitudinal sectional elevation of a portion of a single conductor
conduit embodying. the invention, parts of the structure being broken away for
purposes of illustration.

page_text: Figs. 4 and 5 are enlarged detail views of the contact makers.
Figs. 6 and 7 are sectional end views showing details of the construction of
the conduit.
Fig. 8 is a top plan view of a portion of the conduit partly broken away and with
parts removed to show the interior arrangement.
Fig. 9 is a view in elevation showing a portion of the tubular conductor removed
from the conduit.
Figs. 10 and 11 are enlarged detail views showing means for sustaining the
tubular conductor in working position.
In the drawings,
A, is the tubular conductor which may be composed of any suitable metal,
that having the highest conductivity being, of course, the very best for the
purpose. By the disposition of the necessary parts, I am, however, enabled to
employ cheaper material with good results and find that according to the present
invention I can construct the main supply conductor or conductors of the very
cheapest and the most available material, for instance, galvanized wrought iron gas
pipe. This is due to the fact that I prefer to use a tubular conductor of consider-
able size and to make the running contact upon the interior thereof. Having
considerable cross section the mass of the metal forming the pipe conductor will be
so great that even though of inferior conductivity its resistance will be low enough
to economically convey the currents usually employed on electric railway working
conductors and enable me, therefore, to use the simplest, most endurable, and at
the same time, cheapest and most available form of enclosed conductor yet
proposed.
The tubular metallic conductor A, is formed in sections of any suitable or
convenient length which may be united by welding, lapping, or the usual collars a,
into which the ends of the sections to be joined are fitted. The collars a, may be
screw-threaded at one end but should be plain at the other, so that one end of the
pipe may be fitted thereinto without screw connections in order to allow of move-
ment therein to compensate for expansion and contraction.
The continuous tubular conductor is insulated upon its exterior throughout its
whole length the insulation extending over the couplings so as to prevent the
access of moisture at any point. The insulation B, may be applied in any desired
manner but for many purposes a smooth wrapping of heavy fabric thoroughly
coated with insoluble insulating material, will answer all purposes although there
are many known compositions of matter which may be applied to the exterior
of the tubular conductor to form a very efficient exterior insulation therefor.
The current is collected from the interior of the tubular conductor by means of
a series of contact devices secured in and extending through the walls thereof.
These contacts, while permanently in position, are all normally out of contact and
only rendered active upon the passage of the current collecting device moving with
the vehicle. A series of holes are formed along the tubular conductor and at
regular intervals, and said holes may be at any desired distance, as here indicated,
they are about a foot apart and in each of these holes is secured a spring contact
device C. Each contact device comprises an insulating socket B', which is screw
threaded to engage corresponding screw threads in the openings in the tubular
conductor and provided with a suitable shoulder b, so that it may be screwed down
into perfectly tight contact with the exterior of the conductor. The socket B¹,
extends into the tubular conductor and carries a contact C¹, at its lower extremity
which contact may be of carbon if desired. The contact C¹, is secured to the lower
end of a stem E, which extends upward through the socket B', and is provided
at its outer end with a metallic head d. Between the head d, and the shoulder b,
of the socket, is placed a spring D, which normally sustains the stem, head, and
contact, so that the contact is well clear of the interior surface of the conductor.
A collar or pin e, connected with the lower part of the stem E, limits the action of
the spring D, and when the contact makers are similarly constructed the heads d,
will be normally in substantially the same horizontal plane.

page_text: The conductor being sustained in substantially similar relation to a railway track
it follows that a vehicle travelling upon the said track and provided with a current
collecting device arranged to depress the heads d, successively will, in its travel, be
continuously supplied with current conveyed from the interior of the tubular
conductor through the contacts C', stems E, heads d, and the travelling collector.
A form of collector is indicated in Fig. 3, the same comprising an extended metal
shoe F, having upwardly sloped extremities, f. As shown, the collector F, is of a
length sufficient to engage three of the contacts, and in its forward movement it
will always depress one contact in advance, before leaving the rearmost one, thereby
preventing breaking of the circuit and consequent wear on the parts from sparking
and there will, moreover, always be enough of the contacts in action to carry any
desired amount of current. Obviously the collector can be made longer or shorter
as desired. The contact piece F, of the collector, should be well protected by
exterior insulation and the upwardly extending portion thereof, G, should be
protected by insulation and also by exterior wearing plates g, at that part where it is
liable to be brought into contact with the adjacent structure.
A special feature of the invention consists in the facility with which a damaged
contact maker can be replaced, it being only necessary to unscrew the socket B',
and substitute another, since the entire mechanism of the said contact makers is
self-contained. It may sometimes happen that through irregularities in the
conductor a sufficient number of the contacts may fail to be properly depressed
by the travelling collector and under such circumstances greater range of spring
will be desirable, when the construction indicated in Fig. 4 may be employed. In
said figure, the head d, is replaced by a cross bar d', upon which is spring supported
a head d². Springs D¹, connect the head d2, with its immediate support d', and
adjustable bolts d³, pass through the cross bars d', for adjusting the tension of the
secondary springs D'. The springs D', should preponderate in power so that
the springs D, will be depressed and the contact be brought into engagement with
the conductor before the other set of springs yields, as may be necessary to permit
the passage of the collector.
Various forms of sub-surface conduits may be employed in connection with my
improved conductor several constructions of which will be referred to.
Fig. 1 shows a double conductor conduit having one of my improved conductors
arranged on each side, so that the contacts C, form two parallel horizontal lines
between which moves a double collector comprising vertical shoes F, F1, thoroughly
insulated from each other and provided with separate insulated extensions conveyed
upward through the blade H, which passes through the surface slot I, into
connection with the moving vehicle. The conduit itself comprises a metallic
base piece J, upon which are secured at suitable intervals side brackets K. To
the side brackets are secured hollow U-shaped side pieces L, which are set up
edgewise upon the base J, and secured thereto. In the hollows of the side pieces
are located the conductors A, being sustained in position by proper insulated
supports R. The road bars or capping plates k, k, are sustained upon the upper
edges of the side pieces L, from which, of course, they may readily be removed to
permit access to the conduit. The side pieces L, do not meet either above or below,
consequently there exists between them a continuous open drainage slot at their
lower part through which any matter entering the surface slot will fall, and in
most cases, without lodging upon the contacts C.
Fig. 2 shows a slightly different construction resembling the exterior structure
shown in Fig. 1 of my United States Patent No. 408,639, August 6, 1889, but
provided in addition, with a deflecting strip l, which is formed of a thin continuous
piece of metal the upper edge of which is secured between the edge m, of the
side wall M, of the conduit and the capping plate k'. In this form the conductor
is arranged centrally within the conduit with its contact C, in vertical position and
the blade H', is curved so as to extend over and reach under the deflecting
strip . A very simple and desirable form of conduit is indicated in Figs. 6, 7,
and 8, in which continuously joined sections of metal trough N, are sustained

page_text: within yokes n, carried upon the cross ties of the roadway. With this form the
conduit is preferably about square and has one upper edge O, turned inward, and
its opposite edge P, turned outward. Furthermore, the inturned edge O, is cut
away as much as possible, that is, formed with long scallops between the points O¹,
at which the conductor is supported. The conductor is arranged at one side of the
conduit under the edge O, so that, as indicated in Fig. 8, when the road bars are
removed free access can be had to almost every part of the conductor and the
conductor can be placed or removed through the opening so made. In order to
afford equal support to the road bars k², k³, they are so placed that the slot is
formed at one side of the conduit and consequently the blade H2, is curved inwardly
to bring the collector F, upon the contacts C.
The conduit may be drained at suitable points by connections Q, with a sewer 9,
the connections being indicated in dotted lines. Suitable short tubular supports R,
are provided for the conductor, the said supports fitting over the exterior insulation
thereof and being suitably attached to the walls of the conduit. The said supports
may be of hard, strong, insulating material or they may be of metal and be
insulated from the conduit at the point of attachment. The conductor may be
either slipped through the support in sections before being united, or the said
support may be divisible and joined after the conductors are in place. Where the
sections are short the supports themselves may constitute the couplings and such a
form is indicated at S, Fig. 10. The support S, is formed with a part or short
bracket S', for attachment to the side wall of the conduit and is provided with
insulations at its point of support. The tubular part of the support S, is formed
as a slip joint at one end and is screw threaded at the other, thereby affording an
efficient support for the ends of the conductor and at the same time allowing for
expansion and contraction. Where more than one support is required for each
section of conductor, as where the sections are made of considerable length,
tubular, and preferably, divisible supports are provided between and in addition to
the end supports. The supports will usually be of about the same thickness as the
ordinary couplings and would therefore interpose no obstacle to the free travel
of the collector since they will all be below the plane of compression of the
contacts.
The inner edges of the road bars are arranged in every instance clear of the
contacts and therefore extraneous matter entering the slot will usually pass clear of
the conductor, and the conduits being provided with drainage openings at their
lower part will usually be kept clear of foreign matter without difficulty.
In the form shown in Figs. 1, 6, and 7, brushes might readily be run in the
conduit for the purpose of cleaning the same. Furthermore, it is believed that the
conductor as here described, is most completely protected from all extraneous
matter, as when all the parts are in good condition it will be practically air-tight.
The contacts, as well as the material of the conductor itself, should be of non-
corrosive material but notwithstanding this it may be found desirable to occasionally
force dry air through the tubular conductor which may readily be done by
connecting an air pump to one end of the conductor, which might be found
advantageous under some circumstances, as pointed out in my United States Patent
No. 404,325, May 28, 1889.
The hereinbefore described hollow conductor insulated upon its exterior and
carrying contact makers extending through its walls, I believe to be entirely novel,
and as such claim the same broadly, and it is here particularly pointed out that my
improved conductor is especially applicable to existing conduits in which electric
conductors have failed by grounding or otherwise, or in which the cable system has
been employed. The supporting devices, can, of course, be readily modified to suit
the interior construction of my conduit.
It will be obvious that various minor changes and modifications may be made
in the details of the herein described invention without departing from the spirit
or nature thereof, and I therefore do not limit myself to precisely what is herein
shown and described by way of necessary illustration.

page_text: 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 tubular conductor enclosed in insulating material, and contact making
devices extending from the exterior to the interior thereof, substantially as
described.
Second. A tubular conductor permanently enclosed within an insulating envelope
and having contact making devices extending through both the insulation and the
conductor to make contact with the interior of the conductor and removably
sustained in the wall thereof, substantially as described.
Third. The combination of a tubular conductor enclosed within an insulating
envelope, a contact device comprising an insulating support extending through the
wall of the conductor, a movable contact, a spring for retracting the same, and a
travelling current collector arranged to move the contact into engagement with the
interior of the conductor substantially as described.
Fourth. The combination with a slotted sub-surface conduit, of a hollow
conductor or conductors contained within said conduit and provided with an
exterior insulating envelope, and contact devices extending from the exterior to
the interior thereof, and a travelling collecting device or devices extending through
the slot of the conduit into engagement with the contact devices upon the conductor
or conductors, substantially as described.
Fifth. The combination with a slotted sub-surface conduit, of a hollow conductor
or conductors formed of tubular sections united by tubular couplings provided with
brackets for attachment to the wall or walls of the conduit, sustained within said
conduit and provided with an exterior insulating envelope, and contact devices
extending from the exterior to the interior thereof, and a travelling collecting device
or devices extending through the slot into engagement with the contact devices upon
the conductor or conductors, substantially as described.
Sixth. A sub-surface conduit comprising a metallic trough having one edge
turned inwardly and one outwardly, road-bars sustained upon said edges to form a
surface slot adjacent to one side of the conduit, said inwardly turned edge being
indented to give greater access to the conduit when the road-bar is removed, and a
suitable conductor sustained within the conduit under the inwardly turned edge,
substantially as described.
than 1000