Improved Automatic Braking Mechanism for Electric Cars and the like,
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improved Automatic Braking Mechanism for Electric Cars and
the like,
I, JULIEN DULAIT, of 1, Rue Pruniau, Charleroi, in the Kingdom of Belgium,
Engineer, do hereby declare the nature of this invention to be as follows:
My invention relates to an automatic braking mechanism designed to fix with
the greatest quickness possible electric automobile railway cars, the motors of said
cars being supplied by electromagnetic means through road contacts, buttons and
sectional central rails.
Current may be supplied to electric automobile cars in many ways either by an
aerial trolley, by a subterranean trolley, or by accumulators, or again by various
electromagnetic systems.
.
My invention has for its object to obviate the great drawback presented in
general by the use of these arrangements that is of leaving in circuit after the
passage of the car the contact pieces which have served momentarily to supply the
driving mechanism of the car, and I arrive at this result by causing the vehicle to
be braked as soon as one of these supplying elements has not been placed out of
circuit in proper time. It is obvious that the suddenness of the braking of the
vehicle is determined by the momentum stored up in it and also by taking account
of the danger to which the travellers might be exposed by too quick a stoppage.
Amongst all the various systems to which my invention might be applied, let us
take, in order to fully explain my ideas the system of electro-magnetic supply
most frequently employed. Let us suppose a tramway car such as shown in the
accompanying drawing, Figure 1 impelled by electric motors. Let us suppose the
same actuated by two motors M M¹ one upon each axle which is a very common
arrangement. The supply of the current to the said motors is effected at one of
the poles by means of the two rails, the wheels of the vehicle forming conductors
for the current. The other pole of the motors is supplied by means of a trolley T
which is of course insulated from the remaining portion of the vehicle. This
trolley engages by friction slides or rollers upon a central rail, which rail is
divided into numerous sections S which sections in like manner to the supporting
rails RR are connected by feeding devices to the poles of the dynamo which
generates the power as shewn in Figure 2.
The various inventions of the electromagnetic systems have for their object
arrangements which place successively in circuit and in front of the trolley T
each one of the sections S in front of the vehicle and in the direction of its move-
ment, whilst the sections which have been traversed by the trolley T are con-
secutively cut out of the circuit. It is obvious that if this arangement fails, that
is to say if it does not put in circuit the section in front of that upon which 'the
vehicle is passing, the said vehicle will stop, or if it possesses still sufficient
momentum, it will pass over the inert section and be supplied by the following
section and so on. From the point of view of the danger this failure of action is
without consequence as far as the front sections are concerned; but as regards the

page_text: section which has ceased to supply the car if the arrangement does not act then,
the neighbouring section of the rails will be left in circuit also and with the whole
difference of potential at which the current is generated. In this case the almost
instantaneous stoppage of the vehicle is the consequence of the arrangement which
I describe.
This being understood the drawing may be examined:
It will be seen that the vehicle covers at the least two adjacent lengths of the
sections S. If we suppose the motion of the vehicle to be from left to right in
the direction of the arrow f then section S' is entering into circuit and section S²
is emerging from it. The lengths of section which are represented have for their
object simply to facilitate the description as these lengths may be any suitable
ones.
The vehicle Figure 1 is shown as actually covering to an equal extent the two
sections S1 S2 and the two branches and shoes p' p² of the trolley T touching each
of these two sections. At this instant the electromagnetic mechanisms which
distribute the current to the sections must act by placing S¹ in circuit and with-
drawing S2 therefrom.
Let us suppose that the arrangement has not acted as far as S2 is concerned: the
vehicle will then uncover it, and danger is caused. If we consider the contact
brush b, (roller or pinion); this being of metal, can take the current on the
section S³.
If
In accordance with the drawing it will be seen that the support of this brush at i
is insulated from the remaining part of the car but that it is connected by the
conductor e to one terminal of a disconnecting apparatus D with two contacts.
the second terminal of this apparatus is placed in contact with the vehicle by
means of the cable C¹ for instance it follows that the section S2 remaining in
circuit, the apparatus will act and will release the arm carrying the contact pieces
of the circuit breaker D.
Let us now consider the trolley T. It is placed in contact with the return lead
of the motors by means of the cable 7. This cable is connected to one of the con-
tacts of the circuit breaker D, and continues through the other contact to the
motor M when the circuit breaker is closed. Let us suppose the motors be coupled
in series and we shall then see that their second pole takes or returns the current
to the rails through the axles ar. It follows that the fact of leaving the section S²
in circuit, will suddenly cut off the supply of the current of the motors whether
these latter receive it or not at the moment when the accident happens. The
vehicle is consequently deprived of energy, but it may continue to proceed upon its
journey and in order to obtain full security which is the object of my invention
it is indispensable to stop it within a period of time absolutely as short as possible.
For this purpose the arm of the disjoiner D bears on the side opposite to the con-
tacts of which I have spoken above two other contacts which are
arranged in such manner that penetrating into the contacts T
close the circuit as
they
is indicated in the dotted line e e e, thus putting in
opposition, or short circuiting the two motors which impelled by the active force
of the vehicle stop it almost instantaneously, the one becoming the receiver of
the other which is made into a generator instantaneously. This being under-
stood the various effects of the arrangement are produced as follows: -
The vehicle travels in the direction of the arrow f; S³ remains in circuit;
b comes in contact with S2; the circuit breaker D opens, cutting off the energy
of the motors M M³, and the arms of said circuit breaker impelled by its weight
and by a spring, following the direction of the arrow closes the circuit e at r,
shortcircuiting the motors and consequently stopping the vehicle. This operation
will of course uncover all or part of the section S2, but the conductor becoming
aware thereof will immediately reverse the motor, after having raised the contact
brush b, which is out of circuit, by means of a rod or piece g the control of which
can be effected both from the front as also from behind and after he has of course
reclosed the circuit breaker D.

page_text: +
It will be obvious that the arrangement which forms my invention and which
I have supposed to be placed behind the vehicle so as to render the description
more intelligible may equally well be placed in front but that. the connections of
the one and the other apparatus will be made in such manner that the control both
of the circuit breaker as of the piece g shall be arranged opposite the controller
which is being used at the time or even form part thereof.
It will be also obvious that whatever form the brush 6 possesses it must have
sufficient width in order that when its point of suspension becomes excentric
owing to curves, one of its ends will still bear upon the road contacts or sectional
central rails. When the reduction of the radius of the curve is such that it would
render necessary too great a width for the contact brush it is simpler to mount the
said brush upon the axis of a little travelling wheel gear as shown in the drawing
in Figures 4 and 5. The two little wheels gg' will necessarily keep the brush b
constantly in the axis of the track, therefore in certain contact with the sections
or road contacts.
In the hypothesis which I have contemplated and have chosen to facilitate the
explanation, the means provided are purely electrical, that is to say the stoppage
of the vehicle is effected by the electric motors themselves. But my invention
may equally comprise the stoppage of the vehicle by a mechanical brake which
may be effected on the same principle (see Figure 3).
As in the first case if the apparatus for placing out of circuit the road contacts
or sectional rails should not act, the brush b passing over these contacts is in direct
contact with the source of energy and allows of the passage of the current to
the terminals of the current breaker D) which acting as above described will release
the arms bearing the road contacts thereby interrupting the circuit of the motors.
It is obvious that by means of its momentum the car will be moved forward still
for some time, consequently partly uncovering the section S³, but in consequence
of the regulatable mechanical brake actuated by the electromagnets E the
uncovered part of the section S2 is reduced to a minimum. This result is obtained
as follows:
The electromagnets E connected in series with the terminals of the circuit
breaker D act simultaneously, attracting the lever L which releasing the arm B
of the brake permits the large spring R to produce its effect pressing upon the
arm B, which arm is in one piece with the shoe carrying the cross piece of the
brake and thus brakes the car.
In order to cause the vehicle to recommence its movement, the conductor raises
by means of the threaded bar T and the nut V, the arm B of the brake which by
means of the spring r upon the lever L remains unclosed. After the bar T has
been moved to the end of its path and the circuit breaker replaced upon its contacts
the vehicle can continue its course and the apparatus is ready to act anew.
Dated this 20th day of July 1897.
Improved Automatic Braking Mechanism for Electric Cars and
the like.
I, JULIEN DULAIT, of 1, Rue Prunieau, Charleroi, in the Kingdom of Belgium,
Engineer, do hereby declare the nature of this invention and in what manner the

page_text: same is to be performed, to be particularly described and ascertained in and by the
following statement:-
My invention relates to an automatic braking mechanism designed to fix with
the greatest quickness possible electric automobile railway cars, the motor of said
cars being supplied by electromagnetic means through road contacts, buttons and
sectional central rails.
Current may be supplied to electric automobile cars in many ways either by an
aerial trolley, by a subterranean trolley, or by accumulators, or again by various
electromagnetic systems.
My invention has for its object to obviate the great drawback presented in
general by the use of these arrangements that is of leaving in circuit after the
passage of the car the contact pieces which have served momentarily to supply
the driving mechanism of the car, and I arrive at this result by causing the
vehicle to be braked as soon as one of these supplying elements has not been
placed out of circuit in proper time. It is obvious that the suddenness of the
braking of the vehicle is determined by the momentum stored up in it and also by
taking account of the danger to which the travellers might be exposed by too
quick a stoppage.
•
Amongst all the various systems to which my invention might be applied, let
us take, in order to fully explain my ideas the system of electromagnetic supply
most frequently employed. Let us suppose a tramway car such as shown in the
drawing accompanying the Provisional Specification, Figure 1 impelled by electric
motors. Let us suppose the same actuated by two motors M M one upon each
axle which is a very common arrangement. The supply of the current to
the said motors is effected at one of the poles by means of the two rails, the wheels
of the vehicle forming conductors for the current. The other pole of the motors
is supplied by means of a trolley T which is of course insulated from the remaining
portion of the vehicle. This trolley engages by friction slides or rollers upon a
central rail, which rail is divided into numerous sections S which sections in like
manner to the supporting rails RR are connected by feeding devices to the poles
of the dynamo which generates the power as shewn in Figure 2.
The various inventions of the electromagnetic systems have for their object
arrangements which place successively in circuit and in front of the trolley Teach
one of the sections S in front of the vehicle and in the direction of its movement,
whilst the sections which have been traversed by the trolley T are consecutively
cut out of the circuit. It is obvious that if this arrangement fails, that is to say
if it does not put in circuit the section in front of that upon which the vehicle
is passing, the said vehicle will stop, or if it possesses still sufficient momentum,
it will pass over the inert section and be supplied by the following section and so
From the point of view of the danger this failure of action is without con-
sequence as far as the front sections are concerned; but as regards the section
which has ceased to supply the car if the arrangement does not act then, the
neighbouring section of the rails will be left in circuit also and with the whole
difference of potential at which the current is generated. In this case the almost
instantaneous stoppage of the vehicle is the consequence of the arrangement
which I describe.
on.
This being understood the drawing may be examined:
It will be seen that the vehicle covers at the least two adjacent lengths of the
sections S. If we suppose the motion of the vehicle to be from left to right in
the direction of the arrow f then section S¹ is entering into circuit and section $2
is emerging from it. The lengths of section which are represented have for their
object simply to facilitate the description as these lengths may be any suitable ones.
The vehicle Figure 1 is shown as actually covering to an equal extent the two
sections S¹ S2, and the two branches and shoes p² p² of the trolley T touching each
of these two sections. At this instant the electromagnetic mechanisms which
distribute the current to the sections must act by placing S¹ in circuit and with-
drawing S³ therefrom.

page_text: Let us suppose that the arrangement has not acted as far as S2 is concerned:
the vehicle will then uncover it, and danger is caused. If we consider the contact
brush (roller or pinion); this being of metal, can take the current on the
section 2.
In accordance with the drawing it will be seen that the support of this brush
at i is insulated from the remaining part of the car, but that it is connected by the
conductor e to one terminal of a disconnecting apparatus D with two contacts. If
the second terminal of this apparatus is placed in contact with the vehicle by
means of the cable C for instance it follows that the section S2 remaining in circuit,
the apparatus will act and will release the arm carrying the contact pieces of the
circuit breaker D.
Let us now consider the trolley T. It is placed in contact with the return lead
of the motor by means of the cable . This cable is connected to one of the
contacts of the circuit breaker D), and continues through the other contact to the
motor M when the circuit breaker is closed. Let us suppose the motors be coupled
in series and we shall then see that their second pole takes or. returns the current
to the rails through the axles... It follows that the fact of leaving the section $2
in circuit, will suddenly cut off the supply of the current of the motors whether
these latter receive it or not at the moment when the accident happens. The
vehicle is consequently deprived of energy, but it may continue to proceed upon
its journey and in order to obtain full security which is the object of the invention
it is indispensable to stop it within a period of time absolutely as short as possible.
For this purpose the arm of the disjoiner D bears on the side opposite to the
contacts of which I have spoken above two other contacts which are arranged in
such manner that penetrating into the contacts r they close the circuit as is
indicated in the dotted lines ece, thus putting in opposition, or short circuiting
the two motors which impelled by the active force of the vehicle stop it almost
instantaneously, the one becoming the receiver of the other which is made into
a generator instantaneously. This being understood the various effects of the
arrangement are produced as follows:
The vehicle travels in the direction of the arrow f; $2 remains in circuit;
6 comes in contact with S2; the circuit breaker D opens, cutting off the energy of
the motors M M¹, and the arms of said circuit breaker impelled by its weight and
by a spring following the difection of the arrow closes the circuit e at r, short-
circuiting the motors and consequently stopping the vehicle. This operation will
of course uncover all or part of the section S2, but the conductor becoming aware
thereof will immediately reverse. the motor, after having raised the contact brush_b,
which is out of circuit, by means of a rod or piece g the control of which can be
effected both from the front as also from behind and after he has of course reclosed
the circuit breaker D.
It will be obvious that the arrangement which forms my invention and which
I have supposed to be placed behind the vehicle so as to render the description
more intelligible may equally well be placed in front but that the connections of
the one and the other apparatus will be made in such manner that the control both
of the circuit breaker as of the piece g shall be arranged opposite the controller
which is being used at the time or even form part thereof.
It will also be obvious that whatever form the brush 6 possesses it must have
sufficient width in order that when its point of suspension becomes excentric
owing to curves, one of its ends will still bear upon the road contacts or sectional
central rails. When the reduction of the radius of the curve is such that it would
render necessary too great a width for the contact brush it is simpler to mount the
said brush upon the axis of a little travelling wheel gear as shown in the drawing
in Figures 4 and 5. The two little wheels g g' will necessarily keep the brush b
constantly in the axis of the track, therefore in certain contact with the sections
or road contacts.
In the hypothesis which I have contemplated and have chosen to facilitate the
explanation, the means provided are purely electrical, that is to say the stoppage

page_text: of the vehicle is effected by the electric motors themselves. But my invention
may equally comprise the stoppage of the vehicle by a mechanical brake which
may be effected on the same principle (see Figure 3).
As in the first case if the apparatus for placing out of circuit the road contacts
or sectional rails should not act, the brush passing over these contacts is in direct
contact with the source of energy and allows of the passage of the current to the
terminals of the circuit breaker D, which, acting as above described, will release
the arms bearing the road contacts, thereby interrupting the circuit of the motors.
It is obvious that by means of its momentum the car will be moved forward still
for some time, consequently partly uncovering the section S2, but in consequence
of the regulatable mechanical brake actuated by the electromagnets E the
uncovered part of the section S2 is reduced to a minimum. This result is obtained
as follows:-
The electromagnets E connected in series with the terminals of the circuit
breaker D act simultaneously, attracting the lever L which releasing the arm B
of the brake permits the large spring R to produce its effect pressing upon the
arm B, which arm is in one piece with the shoe carrying the cross piece of the brake
and thus brakes the car.
In order to cause the vehicle to recommence its movement, the conductor raises
by means of the threaded bar T and the nut V, the arm B of the brake which by
means of the spring upon the lever L remains unclosed. After the bar T has
been moved to the end of its path and the circuit breaker replaced upon its contacts
the vehicle can continue its course and the apparatus is ready to act anew.
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 improved method of effecting the automatic braking of automobile
railway cars impelled by electricity by means of central sectional rails, road con-
tacts and the like substantially as described.
2. The apparatus for effecting the automatic braking of electrically impelled
automobile railway cars constructed substantially as described and illustrated in
the drawings accompanying the Provisional Specification.
Deted the 19th dos.
J
A 1000
W. P. THOMPSON & Co.,
Of London, Liverpool, Manchester, and Birmingham.
Patent Agents for the Applicant.