Improvements connected with Electric Traction on the Conduit System.
Year: 1899

page_text: Date of Application, 11th Mar., 1899-Accepted, 3rd Mar., 1900
1.1
COMPLETE SPECIFICATION.
13 1
Improvements connected with Electric Traction on the Conduit
System.
I, EMILE BEDE, of 10, Square Guttenberg, Brussels, in the Kingdom of Bel-
gium, Engineer, 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 current conducting devices for electric traction and it
consists in placing the main conductor of the current serving for the traction upon
a railway in a conduit arranged along the line on a level with the ground, and
made with holes closed by plugs of india rubber or other similar elastic and insu-
lating material through which pass conducting pieces which only come in contact
with the conductor when they are pressed by current collectors attached to the
cars and travelling in the channel which separates the rail from the said conduit.
My invention can be carried out in different ways.
The conductor may consist of naked bars or of an insulated cable having only
certain parts or pieces in contact with it uncovered. A cable can thus be con-
verted into a kind of chaplet having at intervals of a metre, for example, copper
sleeves fixed on the metal core of the cable and enclosed in sheaths having lateral
short tubes or necks hermetically closed by india-rubber plugs through which
pass contact pieces separated by a space of about three millimetres from the
copper sleeve.
The chaplet is placed in an iron channel or between sleepers of wood or other
material protected by an iron covering. Holes are made in this casing to allow
the india-rubber plugs and the contact pieces which traverse them to pass through
the heads of which contact pieces project into the narrow channel, which is left
between one of the rails or guard rails of the way and the said conduit for the
cable. Current collectors attached to the electromotor cars and formed of a strip
of wood (or other insulating and flexible material) provided with a band of copper
in communication with the electromotors of the said cars, press upon the heads
of the contact pieces and, in thus compressing the india-rubber of the plugs, presз
the feet of the said pieces against the sleeves of the cable, the current of which.
will then pass to the electromotors. After the passage of the cars the elasticity
of the india-rubber will separate the sleeves from the contact pieces which can
be touched with impunity. All desirable security will be thus obtained the same
as if the current receivers were placed several inches below the ground and there
will be no need for any other gutter than the small channel along which the cur-
rent receiver travels and which can easily be cleaned out.
In the accompanying drawing,
Figure 1 illustrates the general construction of the conductor C with the
sheaths G containing the contact arrangement.
Figures 2, 3 and 4 represent the said arrangements in detail on a larger scale. ;
Figure 5 shews a modification of the latter; and,

page_text: Figure 6 illustrates an application of the said modification to a double con-
ductor without return current through the rails:
Figures 7 and 8 illustrate a method of joining the lengths of the conductor
and a method of connecting the conduits of the latter:
Figures 9 and 10 represent a system of current collector applicable to the said
arrangements:
Figures 11 and 12 illustrate an arrangement of current receivers at the points
or switches.
The cable C covered with an insulating coating 1 is placed in a sheath formed
of two angle iron bars A¹, A fixed by means of screws to the sleepers and near
one of the rails inside or outside the track.
At suitable distances apart (one metre for example) the insulating coating I is
removed for a length which may be 40 millimetres, and in the part so cut away
is placed a sleeve ML of copper or bronze of cylindrical form and slotted so as to
allow of its embracing the copper. This sleeve is fixed by means of solder. Each
of the said sleeves is covered with an india-rubber sheath G of about 100 milli-
metres in length secured upon the cable by means of rings g, or by ligatures, and
attached to the angle iron bar A¹ by straps S. This sheath is provided. at its
middle part with a lateral short tube or neck G at the bottom of which is a
plate fixed to or cast on the said sleeve. These short tubes or necks G¹ are
introduced into holes made in the vertical side of the angle iron bar A¹, India-
rubber plugs B are applied thereto, located in the plates D) of wood (or other
insulating material) fixed to the angle iron bar by means of screws which press
the india-rubber firmly against the bar A¹.
Through the plugs B are passed the contact pieces E, the heads F of which
project outside, whilst the feet H in the form of a plate are situated face to face
with the plates m from which they are separated by a space of two or three-
millimetres.
It can
The cable can be of any suitable length and directly receive the current from
an electric station. It is obvious that the circuit is open so long as the contact
pieces do not close it by touching at the same time the plate m and a piece com-
municating with the electromotors or with the earth. This piece which serves
as a current collector, and which I call a plough, is formed of a plank K pro-
vided with a copper strip L which, by means of a suitable conductor N, com-
municates with an electromotor apparatus of the car to which it is fixed.
move with slight friction in the channel which separates the rail R and the
conduit A1, A2 of the cable or which is preferable, it can have a certain amount
of play in the said channel but be pressed against the heads F of the contact
pieces by springs or weights. By pressing upon these heads it compresses the
india-rubber of the plugs and forces the feet or discs H of the contact pieces to
touch the plates m so as to allow the current passing through the cable C to
pass to the electromotors through the said contact pieces and the strip L. In
Figure 2 the strip L is shewn pressing the foot or disc H against the plate m
whilst in Figure 3 it is on the point of pressing it.
The manner of carrying out these arrangements can be varied. For example,
as shewn in Figure 5, the ordinary cable conductors can be replaced by rectangular
bars of copper surrounded with a continuous sheath of india-rubber in which
are cut circular holes the edges of which are pressed by plugs B secured in holes
made in one of the rails of the permanent way. It will be clearly seen how the
sheath is pressed against the copper and against the rail by iron bands fastened
by tie bolts which may constitute the tie bars themselves of the permanent way.
I can economically obtain the same result by replacing the continuous sheath
by india-rubber rings placed in front of the contact holes and provided with cor-
responding holes. The bar C can remain naked except that it is provided with
these rings but it is advisable to run a very fusible insulating material such
as stearine tar around it.
It will be seen that in this mode of carrying out my invention the conduit is

page_text: formed principally by the rail, and the channel in which the plough travels has
for its vertical walls the said rail and a guard rail. In the method of carrying
out my invention represented in Figures 2, 3 and 4 the conduit of the conductor
forms the guard rail.
Figure 6 shews this arrangement applied to a double conductor C, C without
return current through the rails. The contact pieces being in the same channel
and actuated by a single plough formed of two planks separated by an insulator
and provided with strips of copper L, L' communicating with the two poles of the
electromotors. In the figure the head of the contact piece is shewn brought
into contact with the conductor C by the pressure of the plough. It is advisable
not to place the heads F, F opposite one another in order to prevent short circuit-
ing which might result through a metal body falling between two push-pieces.
I have stated that the cable can be of any suitable length; it is very advan-
tageous to construct it in lengths of say 9 or 10 metres connected or not to one of
the rails of the permanent way. In fact these lengths can be finished, the insula-
tion thereof be measured, corrections made as required, and the proper working
of the contact pieces verified in the workshops, and the putting together pro-
ceeded with only when the said operation has been reduced to a simple union.
com-
To effect the connection of the lengths of cable the couplings and fishings
represented in Figures 7 and 8 can be employed. The two cable ends C are
enclosed in a conical sleeve X with iron or steel ferrules Y similar to those
employed for driving shafts. These sleeves are covered with an india-rubber
sheath W pressed by rings Z. In order to easily place them in position the angle
iron bars A² are shortened by about 0.100 each so that the coupling
is uncovered for a length of about 0™. 200. When it is quite
pleted it is covered with the end of the angle iron bar A³ and the two
lengths of the cable conduit are united by an iron or steel plate A and an angle
iron bar A³ which form fishes. To prevent water from penetrating at these
points a fusible insulator such as stearine tar can be run in underneath the angle
iron bar A when closing the ends of the lengths by means of boards and mastic,
that is to say,
in order to run the stearine tar around the cable couplings I place
on each side of the space to be filled with the tar, two boards which I roughly
cement with any suitable mastic against the angle iron bars.
I would, however, observe that even if an absolute tightness cannot be thus
ensured the penetration of water into the conduit would have no effect upon the
insulation of the cable.
I have stated that the plough which serves as a current collector in the arrange-
ment illustrated in Figures 1, 2, 3, 4 and 5 can move with slight friction in the
channel in which it is placed but that it is preferable to allow it a certain amount
of play and to provide it with an arrangement which will compel it to press
against the contact heads F. Figures 9 and 10 illustrate such an arrangement.
To the board K are perpendicularly fixed the rods 0 which guide them horizon-
tally because they are, themselves, guided by the sockets Q perpendicular to the
sockets P which slide upon the vertical rods T attached to the car. Springs U
attached on the one hand to the ends of the sockets Q and on the other hand to
the board K draw the latter against the head F whilst the springs V force it
down into the channel r to a depth determined by the diameter of the rollers W
which roll upon the angle iron bar A, or by the position of a suitable stop if it
is desired to dispense with the said rollers. These rollers or this stop should be
fixed to the board K or to the pieces which are attached to it and not to the car,
the oscillating movements of which might cause an interruption of the current
if the plough followed these movements. A set of levers or another suitable
arrangement allows of raising or lowering the plough in order to withdraw it from
the channel r or allow it to be let down therein.
For the purpose of preventing sparking between the feet or discs H of the con-
tact pieces and the plates m of the sleeves M in cases where the current would be
abruptly broken between the pieces of one plug by reason of an imperfection in

page_text: the adjacent plugs, it is advisable to have, following the contact strip L Figures 2
and, at the two ends of the plough, two small plates exactly flush with the
said strip L but separated from it by a small space. These small plates will keep
the contact pieces H and m in contact and if a sudden rupture should take place
of the current it would be between the strip L and the head so that the oxyda-
tion produced by the sparking can be easily got rid of.
The same result can be obtained by leaving on the two sides of the strip L
sufficiently long flat surfaces exactly flush with the said strip. To this end it is
advisable to make the ends of the ploughs of very hard wood suitably bevelled
and easy to replace.
In Figures 2 and 3 I have shewn a coating of wood for the walls of the channel
in which the plough moves. This coating will be generally useful for covering
the fish bolts and tie bars so as to prevent any, retardation or stoppage of the
plough. The cleaning of the channel will be also facilitated by making it regular
in shape. This cleaning can be effected by hand through the medium of a trowel
or spatula or mechanically by means of a straight or circular brush attached to
the car or to the plough. If a rotary brush be employed I propose to suspend
such brush freely from the car and to provide it with a brake which prevents it
from turning as quickly as if it were entirely free, so as to get a difference between
the velocity of the rotating motion and the sliding motion of the brush on the
bottom of the channel.
- Figures 11 and 12 illustrate an arrangement allowing the interruption of the
current when passing the points or switches to be prevented. This arrangement
consists in placing in the body of the switch opposite one of the contact heads F;
a headed pin f which is well insulated by a sheath of india rubber and which
being pressed by a plough bears upon the head I and brings it into contact with
the cable so that when switching a car the plough will still take the current from
the cable of the way that the car has just left.
Figure 11 illustrates the application of this arrangement to a permanent way
in which the conduit of the cable is placed inside the rail.
Figure 12 illustrates the modifications in the switch which are required when
the said conduit is to be placed outside the rail. It is then necessary to employ
double switches such as those shewn in the said figure. The pin serving as an
intermediary between the plough and the conduit that it has just left, can be
applied to them quite as easily as to the single switches.
The construction of these switches and of the crossings presents no serious
difficulties, as the depth of the channels in which the plough moves can be reduced
by 70 millimetres.
In cases where the current has not a special conductor for the return it will be
useful to make good electrical connections between the parts of the conduit so
that the current returns principally through that conduit symmetrically surround-
ing the interior conductor, which will reduce to a minimum the induction on
the telephone wires-and prevent derivations of current in the ground and con-
sequently any injurious effects on the water and gas pipes. The returning current
will pass from the electromotors to the rails and from the rails to the conduit
through the ground! It could be also transmitted directly from the electromotor
to the conduit by suitable shoes sliding on the conduit.
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 I am
aware that a main conductor located in a conduit placed at the ground level inside
or outside the rail and provided with plungers and springs which, yielding to
the force of a current collector, comes in contact with metal pieces in communi-
cation with the metal of the conductor has been already employed for transmit-
ting current to the electromotors of cars serving for traction upon a railway, and
I make no claim to such an arrangement but I claim as means for applying this
mode of transmitting current :-
1. A conduit placed on the ground. level along one of the rails of the track and

page_text: presenting in front of this rail holes closed by plugs of india rubber (or other
similar elastic and insulating material) through which pass contact pieces which,
when their heads are pressed by a current collector drawn along between the con-
duit and the rail by an electromotor car, come in contact with the main current
conductor located in the said conduit, whilst the elasticity of the india-rubber
separates the said pieces when the current collector ceases to press upon them,
substantially as set forth.
2. A conduit which can be formed of two angle iron bars, and the vertical wall
of which opposite the rail is made with holes closed by the said india-rubber
plugs, which conduit encloses an insulated cable upon the metal of which are
fixed at intervals in front of the hereindescribed holes contact pieces surrounded
by india rubber sheaths provided with lateral short tubes or necks secured in the
said holes by the bases of the plugs so that the contact pieces of the latter are
opposite and very near to contact pieces carried by the cable and that the whole
is well insulated and protected from penetration of water, substantially as set
forth.
3. A conduit formed of one of the rails of the track and of iron bands which
are attached thereto, and a conductor formed of copper bars insulated by sheaths
of india rubber or other insulating material provided with holes opposite the con-
tact pieces substantially as set forth.
4. A current collector suitable to the conductors hereinbefore specified, con-
sisting of a plough attached to an electromotor car and formed of a plank of wood
(or other insulating and flexible material) provided with a copper band sliding
against the heads of the contact pieces and pressed against them by springs or
weights, the said plough being forced down into the channel in which it moves
by springs or weights to a depth determined by stops which are attached to it,
and being maintained in a vertical position by guides attached to the car, sub-
stantially as set forth.
5. For the purpose of allowing the passage into the switches without inter-
rupting the current, the use of pins which pass through india-rubber sheaths
fixed in holes made through the switches and which press upon the contact pieces
of the conductor in such a manner that the plough in travelling along the switch
makes contact, through the medium of the said pin, with the cable of the conduit
corresponding to the rail that it has left, substantially as set forth.
6. For cleaning the channel in which the current collector moves, a circular
rotary brush suspended freely from the car and the axis of which is provided
with a brake which prevents it from turning as quickly as if the wheel were
entirely free upon the said axis, substantially as set forth."
7. In cases where no special conductor serves for the return of the current,
careful electrical connection between the parts of the conduit so as to allow the
same to serve as a principal conductor for the return of the current and thus
prevent induction on the telephone wires and injurious derivations of current
in the ground, substantially as set forth.