Improvements in Automatic Signalling Devices for Preventing the Collision of Railway Trains.
Year: 1896

page_text: Date of Application, 9th Oct., 1896-Accepted, 27th Mar., 1897
COMPLETE SPECIFICATION.
Improvements in Automatic Signalling Devices for Preventing the
Collision of Railway Trains.
I, ALEXANDRE LEFEBVRE, of Beersel near Heyst-op-den-Berg in the Kingdom
of Belgium, 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 :-
The object of this invention is to render impossible the meeting or collision
between railway trains. In order to effect this object I provide an automatic
signalling device which renders it absolutely impossible for two trains upon the
same metals to approach one another nearer than such a distance as shall have been
previously decided upon, without the drivers of both trains being immediately made
aware of the fact.
This signalling device acts automatically and simultaneously upon the two engines
upon whatever portion of the road the trains may be, whether they are journeying
towards one another or if one of them is stopping or finally if both are proceeding
in the same direction at different speeds. It only ceases to act when both trains
are at rest, or when they are no longer both upon the same track or when the
distance separating them has become greater than the minimum distance above
referred to. The signal acts perfectly independently of all the usual signal or
warning apparatus and will thus prevent the terrible results which might arise from
inattention, forgetfulness or error on the part of the employees in charge of such
signals or appliances or on the part of the switchmen.
A further great advantage of my invention is its extreme simplicity and the
relatively small cost of adopting it. It may be applied to every kind of railway
or train.
The use of my invention will also prevent the collision of a train with an isolated
carriage or truck or with a portion of a train which has become detached from its
engine.
In order that my invention may be more readily understood I will now describe
the same, together with the method of carrying it into practice, with reference to
the accompanying drawings:
Figure 1 is a diagrammatic view showing the arrangement of the conductors.
Figure 2 shows the division of the conductor into sections.
Figure 3 shows the arrangement of two conductors between the rails.
Figure 4 shows the arrangement of the two conductors on the outside of the
rails.
Figure 5 shows the arrangement of the conductors at a junction of the line.
Figure 6 shows the arrangement of an electric switch at the junction.
Figure 7 shows the arrangement of the conductors at a level crossing.
Figure 8 shows a stake or support for carrying the conductor.
Figure 9 shows the construction of the ends of the conductors.
Figure 10 is a side elevation of a trolley.
Figure 11 shows an engine provided with a trolley, and an electric bell.
Figures 12 and 13 show a side elevation and end view respectively of an
arrangement for preventing collision with a single waggon or a portion of a trai
which may be left on the permanent way, and
Figure 14 shows a switch hereinafter described.

page_text: I place parallel to the rails, in the middle of the track, slightly above the level
of the latter aud along its entire length, an uncovered inetal conductor A B
(Figure 1) rigid or well stretched and fastened to supports a, b, c, d, e.... which
insulate it electrically from the ground and from the rails. This conductor ends at
the two extremities of the line and is firmly fastened to its en 1 supports in such a
manner as to remain completely insulated electrically.
Upon each engine intended to work upon the line I arrange an electro-magnetic
bell (of the kind employed for telephonic purposes) the motor for. such bell being
actuated by the axle, the connecting rod, the slide-valve rod, or in short by any
other part of the locomotive which will ensure the actuation of the motor while
the engine is running and its repose when the engine is at rest. One of the poles
of the bell is in direct communication with the framework of the engine and
consequently with the rails and the ground (see Figure XI). The other pole is
connected with a trolley or any suitable contact device (preferably cylindrical and
of a width sufficient to allow for the side oscillation or rolling of the engine)
electrically insulated from the framework of the engine, but travelling upon the
insulated conductor A B and making contact with it.
As the conductor is insulated, the circuit is not closed at any point, the current
cannot circulate and the bell will not act although its motor may be in motion.
But if, at any point whatever along the line, contact is made between the
conductor A B and the rails or the ground, the electric circuit is thereupon
closed, and, if the engine is in motion, the bell will instantly act.
We will now suppose that a second engine is upon the line and at any distance
whatever from the first. As this second engine carries the same apparatus as the
other, it will, by means of its trolley, its electric bell and its framework, make
contact between the insulated conductor A. B and the rails or the ground; the
circuit will be closed and the bells on both engines will be caused to ring. Both
bells will continue to ring as long as both engines or either one of them are or is in
motion.
But, as there is no objection to two trains being upon the same line when the
distance which separates them is sufficiently great, the signal would frequently act
unnecessarily under the conditions above described.
In order to avoid this inconvenience, I divide the insulated conductor A B into
different sections of fixed length. The signal will now only be actuated, when two
trains are upon the same section of the conductor A B. Figure II shews such
division of the insulated conductor into sections.
With this arrangement, however, it might happen that two engines should
approach one another, upon two different sections of the conductor Å. B, in such
a manner as to meet at the point of division (D for instance) of the conductor,
or somewhere in the neighbourhood of such point. In this case, as the trolleys
of the two engines have not been upon the same section of the conductor or
have only been upon it during a few seconds, the circuit will not have been
closed or the bells actuated, or this will only have taken place too late to prevent
a collision.
In order to guard against this, I provide at the side of the conductor A. B, and
parallel to it, a second conductor A¹ B¹ (Figure III) arranged in exactly the same
way as the conductor A B except that this second conductor is divided at a point
corresponding to the middle point of the sections of the first conductor, as shewn in
Figure III.
With this additional arrangement, it will readily be seen that two engines will in
no case be able to approach one another nearer than the distance corresponding to
one half the length of one of the sections into which the conductors A B and A B₁
are divided, without their trolleys being simultaneously in contact with the same
section of one or other of the conductors, and thus closing the circuit and actuating
the bells.
In practice I prefer to place the conductor A B upon one side of the line and the
conductor A B upon the other side (Figure IV) as I have found that there are

page_text: objections to placing these conductors between the rails. In this case two trolleys
must be provided upon each engine instead of one; these trolleys will both he
electrically insulated from the framework of the locomotive but electrically
connected one with another.
At bifurcations of the line I adopt the arrangement shewn in Figure V. The
point of division of one of the conductors A B should coincide with the place
where the hifurcation occurs. The other conductor A B will separate into two
portions which are soldered together, one of such portions crossing the line
underground, (this underground portion consisting of an insulated or covered
conductor). Reference to Figure V of the drawings will shew that two trains would
in no case he able simultaneously to pass the points M and N, M and O or N and O
without their bells being actuated.
In certain points, such as in stations for example, where it is required that trains
should be able to stop whilst permitting the passage of other trains upon neigh-
bouring and near lines, it will be necessary to provide upon the point switches an
electrical switch C to be actuated by the point switch itself and putting into
communication the portions of the conductor A B of the one open line and leaving
cominunication interrupted between the two portions A B of the other liue, so that
a train might stop at O whilst allowing another train to pass from M to N or
from N to M. Figure VI shews this arrangement.
Behind the eccentric lever a box B Figure XIV is arranged which is carried
by a post P. In this box B a switch provided with switch guide or handle M is
plared. This switch guide M is connected to the lever L by means of a rod T.
This rod is attached to the switch guide M by means of an insulating knob b. It
is thus evident that, according as the lever L is moved into one or the other of these
two positions, the switch guide M will be either in contact with the block B or
with the block C and will consequently place the conductor A' in communication
with either the conductor B' or the conductor C¹.
At level crussings the conductors are passed underground by means of a length
of covered cable, an inclined plane being provided on each side of the crossing so
that the trolley may readily be replaced upon the conductor (Figure VII).
The conductors are fixed upon both sides of the line upon wooden stakes or
pickets by means of a clamp, as shewn in Figures VIII and IX. These pickets
are provided, on the whole of their circumference or upon each of their faces,
with a groove S formed with chisel or saw, the object of auch groove being to
increase the insulation.
The clamping arrangement which I have adopted to serve as a support for the
conductor consists of a piece of wood R placed in the ground and provided with a
groove S intended to increase the insulation; upon the top of this piece of wood a
clamp T is fixed which is formed of two jaws t, t' one of which is fixed and the
other movable. These two portions are connected by one or two bolts U which
are loosened when it is desired to insert or withdraw the conductor. These jaws
are each provided at their upper extremity with a recess for the reception of the
conductor when they are closed. It will of course be understood that the
conductor, which is only partially surrounded by the clamp, rises above the jaws
so as to permit of the trolley being in continuous contact with it.
In order to facilitate repairs which may have to be effected on the line and
allow of a ready removal of the conductors they are divided into sectious of a
certain length. The extremities of each length are brazed to iron parts or
castings P (Figure IX) which are bolted to a T-shaped flat iron part V, which is
fixed upon one of the pickets. On reference to Figures VIII and IX it will be
seen that on unscrewing the bolts U and U the lengths of the conductors may at
once be removed without any difficulty.
Two trolleys must be provided upon each engine, one for each conductor. The
principle of the trolley is shewn in Figure X of the drawings.
In order to prevent collision between a train and a carriage or truck or a portion
of a train, abandoned on the line, the carriages or trucks should be furnished with

page_text: a metal part, which, whilst the carriages or trucks are at rest, will rest upon the
insulated conductor and thus establish electric connection between the insulated
conductor, the framework of the carriage or truck and the rails and the ground,
se closing the circuit; if now a locomotive enters the section of the conductor upon
which the carriage is, the bell on the locomotive will be caused to ring and the
driyer will be made aware of the presence of the obstacle. When the carriages
are in motion, the metal part is raised and is no longer in contact with the
conductors A B and A' B₁.
To the floor of each waggon, two strong iron rods g and g¹ (Figures XII
and XIII) are fixed vertically which serve as guides. Along these guides an
iron piece a can slide.
Centrally upon this piece a transmission-pulley P is arranged and to the floor
or bottom of the waggon four pulleys p are fixed.
A rope e passes over the pulleys p and the pulley P in such a manner that, when
the said rope is stretched, the piece a will be in its lifted position and when the
rope c is released, the piece a falls back. When the piece is in its lower position
it rests upon the conductors C and the rails. At each extremity of the piece a,
a cu ved spring plate is arranged which serves to deaden the shock when the
piere a drops down upon the conductors.
When the waggons are coupled in succession to the locomotive, the ropes c of the
waggons are hooked on to each other, end to end as shown in Figure XII so that
these ropes are all in a stretched position; the extremity of the rope of the last
waggon is fastened on to a hook K, fixed to the rear wall of the waggon. All the
pieces a are then in a lifted position.
If, during the journey, the train should be accidentally split up, the rope c will
break and the pieces a of the two waggons, between which the separation took
place, will drop down upon the conductors and thus establish contact.
In the same way, should one waggon or a number of waggons in succession be left
on the line, and if consequently the rope c of the first waggon is not in its hooked
position, the piece a of this said waggon will rest upon the conductors and establish
contact.
Having now particularly described and ascertained the nature of my said inven-
tion and in what mauner the same is to be performed, I declare that what I
claim is :-
1. An automatic signalling system by means of which any meeting or collision
of railway trains may be prevented, comprising a double conductor placed along
the line, either between the rails or upon both sides of the same, such con-
ductors being intended to connect electro-magnetic bells provided upon the
locomotives which are upon the same line; this communication taking place by
means of a contact device of the trolley or permanent contact type, all for the
purpose described and acting as has been specified and illustrated in the accom-
panying drawings.
2. In an automatic signalling system for preventing the meeting or collision of
railway trains, and in combination with such system, the employment of a double
conductor in sections of fixed length, the sections of the two conductors being
arranged alternately one with respect to another; the conductors being made up of
rods or wires, as above described and for the purpose specified.
3. In an automatic signalling system for preventing the meeting or collision of
railway trains, and with this system, the combination of the bifurcation contacts
consisting in making use of the rod of the point switch or of its lever in order to
actuate an electrical switch acted upon by the lever or by the rod of the point
switch with the object of opening and closing the communication of the main line
with the branch, for the purpose specified and as above described, and illustrated
in the accompanying drawings.
4. In an automatic signalling system for preventing the meeting or collision of
railway trains and in combination with this system, the special arrangement

page_text: employed at level crossings, such arrangement consisting in causing the double
conductor to pass underground at the place used for traffic whilst insulating it
from the earth, as above described and illustrated in the accompanying drawings.
5. In an automatic signalling system for preventing the meeting or collision of
railway trains, the employment in combination with this system of clamps fixed
to the upper part of stakes or pickets and consisting of two jaws, one fixed.and
the other movable, connected by one or two bolts and recessed at their upper
part for the reception of the conductor in such a manner that a portion of
its circumference remains free in order that the contact with the trolley may be
uninterrupted, substantially as above described and illustrated in the accompanying
drawings.
Dated this 9th day of October 1896.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.