Improved Apparatus for Working Railway Switches by Means of Electrical Energy, and for Signalling in connection therewith.
Year: 1893

page_text: Date of Application, 24th Nov., 1893.
Complete Specification Left, 21st Aug., 1894-Accepted, 29th Sept., 1894
PROVISIONAL SPECIFICATION.
[Communicated from abroad by Messrs. SIEMENS & HALSKE, of Berlin, in the
German Empire, Electrical Engineers.]
Improved Apparatus for Working Railway Switches by Means of
Electrical Energy, and for Signalling in connection therewith.
We, SIEMENS BROTHERS & Co., LIMITED, of 12, Queen Anne's Gate, West-
minster, in the County of Middlesex, Electrical Engineers, do hereby declare the
nature of this invention to be as follows :-
This invention relates to apparatus for working switches on railways wherein the
setting and locking of the switches is effected by means of an electromotor which is
actuated by means of a contact switch apparatus at the central station, the electro
motor being connected to the central station by three conductors for this purpose.
In addition to the setting and locking of the railway switches, the apparatus also
operates a control signal or indicator which shews whether the switch is locked or
whether it has been forced open by a passing train.
Furthermore, a locking device is provided whereby the reversal of a switch is
rendered impossible if a vehicle is situated on the line within a certain distance of
the switch; also, an arrangement whereby a conductor leading to the semaphore
signal is cut out of circuit, so that the signal cannot be changed, as soon as a passing
train has forced open the switch; and lastly a signalling device is provided near
the switch whereby orders for working the switch can be transmitted to the central
station.
All these devices are operated by means of the said three conductors.
The accompanying drawings shew diagrammatic plans of the said apparatus in its
various stages of operation.
A is the contact switch apparatus at the central station; B is the railway switch
actuating and locking apparatus with electro-motor; C is the current generator,
and D is the apparatus for giving the orders for working the switch.
The switch apparatus at the central station consists of a double contact switch a;
an electro magnet b whose armature carries an indicator disc with a small stud f;
a second electro magnet c, whose armature c¹ also carries an indicator disc, and a
small lever which on the motion of the armature c' carries a contact switch d
with it.
At the electro magnet b is a stopping device operating in such manner that
the stud ffixed to the disc of armature catches into the notch of the catch k
when the current passing to the electro magnet is of so short a duration that the
armature 6, in consequence of its inertia, does not have time to reach the poles of
the magnet, and is consequently not capable of fully raising the catch k. If on the
other hand the circuit is closed sufficiently long for the armature & to be completely
attracted by the electro maguet, the catch k will be moved so far by the stud that
it will be caught by a second catch m. On the circuit being interrupted again, the
armature can then move back so far that the stud f, in pressing back the catch m
will liberate the catch k. Thus in the first mentioned case the indicatof disc will
assume a middle position after the electro magnet has been included, in the circuit,
and remains for a short time so included. When the electro magnet remains
included for a greater length of time, the indicator disc will assume the position of
the completely attracted armature, and on the ensuing breaking of the circuit it will
assume that of the entirely released armature when this is drawn away from the poles
by a spring.
The apparatus A has also a locking rod e which, when moved in the direction

page_text: towards the double contact switch a projects in front of an extension thereof so that
the double switch a cannot then be reversed.
The rod e is moved towards the switch, either by the armature when this is
completely attracted by the poles of the electro magnet b, the beak of the armature
being made to carry the rod along with it, or by the armature c¹ which butts against
the rod when it is removed from the electro magnet e by a spring.
The double switch a can therefore not be moved, on the one hand, when no
current is passing through electro magnet c and on the other hand, when current is
passing through electro magnet b.
The apparatus B is divided into the known apparatus n actuated by a wire pull
for reversing and locking the switch, and an electro motor o. The disc n carries in
place of the ordinary chain groove, a loose toothed ring connected by a shearable
pius with the disc n. The disc n contains a cam groove with which engages the
one end of a lever which is connected to the reversing device of the electro-motor.
On the axis of the latter is a bevil wheel (not shewn on the drawing) gearing with
a bevil wheel on a shaft whose other end has a worm engaging with the toothed
ring n' of the disc n, so that the rotation of the motor axis will effect the rotation
of the disc n.
?"
The armature axis of the motor carries a loose T shaped lever t on which lever
are studs or rollers 2¹2 23 of which, in the normal action of the apparatus, and
raise the contact brushes and from the commutator, leaving the brushes v³ v
in contact, or 3 and are raised off thereby and are left in contact.
The lever t is connected to the lever u by means of a suitably strong tumbling
spring connection in such manner that the lever u on moving, has the tendency to
carry levert with it, and that after the complete reversal of the lever u the lever t
will be made to spring to the one side or the other, coming in contact with the
stops or, or, if the armature has been attracted by the poles p p of the field
magnets, with the stops on such armature.
If the electro motor, which requires a suitably strong current (such as 4 ampères)
to drive it, has a considerably weaker current passing through it (such as 0.1 ampère)
not only will the armature of the motor remain stationary but the armature h will
not be attracted by the poles pp. If now after shearing the pins (the toothed
ring n' being stationary) the disc n be rotated by the motion of the switch, causing
a movement of the lever u, the levert will be moved until it strikes against ³ or
But before it reaches the stop the stud 23 will have raised the brush or v², that is
to say, it will raise off a third brush, in addition to the two which had been
previously raised. All the conductors of the circuit are in that case without
current.
If on the other hand the full working current be passed through the conductors
to the electro motor, the armature h will at once be attracted by the poles p, p, and
the lever t will, immediately after the commencement of the movement of the disc
and lever u, be arrested by the stop or 2, whereby the stud will be prevented
from lifting off the brushes of or 2 and thus the before mentioned interruption of
the current will be prevented.
By the farther rotation of the armature of the motor the lever u will be moved
out of its middle position, and the levert will be thrown over by its spring connection
therewith, so as to effect the before described lifting off and bringing in contact
respectively of the two sets of brushes.
The action of the above described apparatus for working the switch is as
follows:--
During the position of rest of the switch for a certain direction of traffic, a current
will pass through the circuits indicated at Fig. 1.
The current passes from the supply lead through the windings of the electro
magnet c whose attracted armature c' will bring the contact switch d upon the
contacts 4 and 5; the current will further flow through the double contact switch a
and contact 2 through the windings of the electro motor and back to the current
generator.

page_text: The resistance of the windings of the electro-magnet c is so great that the electro
motor cannot be actuated. If during such position of rest of the railway switch, a
vehicle be situated in front of its points, or approaches these within a certain
distance, the arrangement is such that the switchman at the central station is no
longer able to reverse the said switch; this is effected as follows.
From the leads of the two insulated commutator brushes ' and there are
branched off two leads which are connected with the two lengths of rail w in front
of the switch, and which leads are provided withysuitable resistances as shewn.
These rails are insulated from the rest of the line and must not be connected to
each other by a conducting connection. If now they are put in conducting
connections by means of a vehicle standing upon them, a current will circulate
through the conductors as indicated by the arrows in Fig. 2 and the armature b¹
will be attracted by its electro magnet. The stopping bar e will thus be pushed
forward and will consequently prevent the movement of the double contact switch a
as long as the vehicle is situated in front of the switch.
At the same time the indicator disc connected to the armature will indicate
such stoppage. It will be seen from the connections that if the vehicle touches the
insulated rails at the moment when the railway switch is being reversed, the latter
will not be stopped half way, there being nothing to prevent it from completing its
motion.
The insulated rails have connected to them two other conductors which lead to
an order signalling apparatus D situated near the railway switch. When the
indicator is reversed, no matter from which side, there occurs a momentary
connection of the conductors. The armature b' is attracted, but in consequence of
its inertia the momentary current is not sufficient to bring it up to the poles of the
electro magnet b, and, as above described, the stud f engages with the notch of the
catch after the current has ceased, as shewn at Fig. 3. This middle position of
the indicator disc of armature b' serves as a signal to the switchman at the central
station from the shunters to reverse the railway switch. On this being done, the
armature is first completely attracted and is then withdrawn, whereby the locking
action of the catch k ceases, and the disc moves to the end position.
On setting the railway switch in the opposite position to that shewn at Fig. 1
the following operations take place.
The double contact switch a is first brought into the position in which it lies on
the contacts 2 and 3, as shewn at Fig. 4; the lead to the electro magnet c is thus
interrupted and the armature c¹ is drawn away therefrom by its spring, and its
indicator disc is correspondingly moved from the position it occupied. The
armature e also moves the contact switch d from the contacts 4 and 5 on to 6 and 7
thereby breaking the semaphore signal circuit E connected to 4. As shewn by the
arrows in Fig. 4, the full working current now passes through the windings of the
electro motor field magnets so as to set this in motion. At the same moment that
this current takes place, the armature his attracted by the poles p p.
The cam groove on the revolving disc n brings the lever u, shortly before the
termination of the unlocking phase, into the middle position in which it remains
until the switch is reversed. The lever t which will have come in contact with
stop, will remain in position while the disc continues to revolve.
No alteration of the position of the brushes consequently takes place on the
movement of the lever u into the middle position.
When the disc u has moved gradually into the relocking position, the lever u
will be moved by its cam groove beyond the middle position. In consequence
hereof the strained tumbling spring will throw the lever t over, whereby the
studs Z Z will raise the brushes and off the commutator and will allow the
brushes and v to come in contact therewith as shewn at Fig. 5.
In the circuit of the applied brush v¹ there is now included the comparatively
large resistance of the windings of the electro magnet c, so that the electro motor
will again remain at rest, while the circuit through which the working current
formerly flowed is broken by the raising of the brush v. The electro magnet c

page_text: being now excited by the current, it attracts the armature c¹ with its indicator
disc; the contact switch d is thereby brought on the contacts 4 and 5 again, thus
re-establishing the interrupted signal circuit E.
On the switch being again reversed, that is to say, when the double contact.
switch a is brought on contacts 1 and 2, the same operations as above described
take place; the working current then passes through the brushes v¹ and v³ so that
the motor armature is made to revolve in the contrary direction.
If the switch is forced open a vehicle, for example in the position shewn at
Fig. 4, then by the forcible rotation of the disc n the pin s will be sheared (n¹ being
stationary) and the lever u will be moved into the middle position, beyond which it
cannot pass, as, according to the direction of rotation of the disc n, the stop y¹ or y²
on the disc in coming in contact with the projection of the stationary toothed
ring n', will prevent the further motion of the disc, as shewn at Fig. 6. As in this
case the armature h with its stops i¹² is not attracted, the stud of levert will,
at the commencement of the motion of lever u, raise the brush 4 out of contact, as
the lever t will only be stopped in its tumbling action by the stop 3. By such
raising of a third brush v, the indicating current passing through the windings of
electro magnet c will be interrupted, the armature c' with its indicator disc will be
drawn off by its spring, and the circuit y leading to a semaphore or other signal
will be broken.
From the foregoing description it will be seen that by means of the armature c¹
and its disc an indication will always be given at the central station of the proper
locking of a switch in position; whether a circuit is broken, and whether the
electro motor is in proper order; and that the armature and its disc will also
indicate whether vehicles are in front of the switch, and whether an order for
reversal has been given.
.
a² are windows in the screen behind which the indicator discs work, so as to
shew their different positions.
Dated this 24th day of November 1893.
ABEL & IMRAY,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Improved Apparatus for Working Railway Switches by Means of
Electrical Energy, and for Signalling in connection therewith.
We, SIEMENS BROTHERS & Co. LIMITED, of 12 Queen Anne's Gate,
Westminster, in the County of Middlesex, Electrical Engineers, 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 :-
In the Specification to our Patent No. 4976 of 1893 was described apparatus
for working switches on railways wherein the setting and locking of the switches
is effected by means of an electromotor which is actuated by means of a contact
switch apparatus at the central station, the electromotor being connected to the
central station by three conductors for this purpose. In addition to the setting
and locking of the railway switches, the apparatus also operated a control signal
or indicator which shews whether the switch is locked or whether it has been
forced open by a passing train.
Our present invention relates to an improved construction of such apparatus,
wherein, in addition a locking device is provided whereby the reversal of a switch
is rendered impossible if a vehicle is situated on the line within a certain distance
of the switch; also, an arrangement whereby a conductor leading to the
semaphore signal is cut out of circuit, so that the signal cannot be changed, as
soon as a passing train has forced open the switch; and lastly a signalling device
is provided near the switch whereby orders for working the switch can be

page_text: transmitted to the central station. All these devices are operated by means of the
said three conductors.
The drawings accompanying our Provisional Specification shew diagrammatic
plans of the said apparatus in its various stages of operation. A is the contact
switch apparatus at the central station; B is the railway switch actuating and
locking apparatus with electro motor; C is the source of electricity, and D is the
apparatus for giving the orders for working the switch.
to
The switch apparatus at the central station consists of a double contact
switch a; an electro magnet whose armature b' carries an indicator disc with a
small stud f; a second electromagnet c, whose armature c' also carries an indicator
disc and a small lever which on the motion of the armature c¹ carries a contact
switch d with it. At the electromagnet & is a stopping device operating in such
manner that the stud ffixed to the disc of armature catches into the notch of
the catch k when the current passing to the electromagnet is of so short a duration
that the armature ', in consequence of its inertia, does not have time to reach the
poles of the magnet, and is consequently not capable of fully raising the catch k.
If on the other hand the circuit is closed sufficiently long for the armature
be completely attracted by the electro magnet, the catch k will be moved so far
by the stud that it will be caught by a second catch m. On the circuit being
interrupted again, the armature can then move back so far that the stud f, in
pressing back the catch m, will liberate the catch k. Thus in the first mentioned
case the indicator disc will assume a middle position after the electro magnet b
has been included in the circuit, and remains for a short time so included. When
the electromagnet remains included for a greater length of time, the indicator disc
will assume the position of the completely attracted armature, and on the ensuing
breaking of the circuit it will assume that of the entirely released armature when
this is drawn away from the poles by a spring.
The apparatus A has also a locking rod e which when moved in the direction
towards the double contact switch a projects in front of an extension thereof so
that the double switch a cannot then be reversed.
The rod e is moved towards the switch, either by the armature when this is
completely attracted by the poles of the electromagnet b, the beak of the armature
being made to carry the rod along with it, or by the armature c' which butts against
the rod when it is removed from the electromagnet c by a spring.
The double switch a can therefore not be moved, on the one hand, when no
current is passing through electromagnet c and on the other hand when current is
passing through electromagnet b.
The apparatus B is divided into the known apparatus n actuated by a wire pull
for reversing and locking the points, and an electromotor o. The disc n carries in
place of the ordinary chain groove, a loose toothed ring n' connected by a
shearable pin & with the disc n. The disc n contains a cam groove with which
engages the one end of a lever u which is connected to the reversing device of the
electromotor. On the axis of the latter is a bevil wheel (not shewn on the
drawing) gearing with a bevil wheel on a shaft whose other end has a worm l
engaging with the toothed ring n¹ of the disc n, so that the rotation of the motor
axis will effect the rotation of the disc n.
T
The armature axis of the motor carries a loose T shaped levert on which lever
are studs or rollers 2¹2 23 of which, in the normal action of the apparatus
and raise the contact brushes v¹ and v² from the commutator, leaving the
brushes in contact, or and * are raised off thereby and are left in
contact.
The lever t is connected to the lever u by means of a suitably strong tumbling
spring connection in such manner that the lever u on moving, has the tendency
to carry levert with it, and that after the complete reversal of the lever u the
lever t will be made to spring to the one side or the other, coming in contact with
the stops or i, or if the armature has been attracted by the poles p p of the
field magnets, with the stops on such armature.

page_text: If the electro motor, which requires a suitably strong current (such as 4 ampères)
to drive it, has a considerably weaker current passing through it (such as 0.1 ampère)
not only will the armature of the motor remain stationary but the armature h will
not be attracted by the poles p p. If now after shearing the pins (the toothed
ring n¹ being stationary) the disc n be rotated by the motion of the points, causing
a movement of the lever u, the lever t will be moved until it strikes against i³ or i.
But before it reaches the top the stud will have raised the brush or v², that is
to say, it will raise off a third brush, in addition to the two which had been
previously raised. All the conductors of the circuit are in that case without
current.
If on the other hand the full working current be passed through the conductors
to the electromotor, the armature h will at once be attracted by the poles p p, and
the lever t will immediately after the commencement of the movement of the disc
and lever u, be arrested by the stop or, whereby the stud will be prevented
from lifting off the brushes or 2 and thus the before mentioned interruption of
the current will be prevented.
By the farther rotation of the armature of the motor the lever u will be moved
out of its middle position, and the levert will be thrown over by its spring connection
therewith, so as to effect the before described lifting off and bringing in contact
respectively of the two sets of brushes.
The action of the above described apparatus for working the points is as
follows:-
During the position of rest of the points for a certain direction of traffic, a
current will pass through the circuits indicated at Fig. 1.
The current passes from the supply lead through the windings of the electro-
magnet whose attracted armature will bring the contact switch d upon the
contacts 4 and 5; the current will further flow through the double contact switch a
and contact 2 through the windings of the electromotor and back to the source of
electricity.
The resistance of the windings of the electromagnet c is so great that the
electromotor cannot be actuated. If during such position of rest of the railway
switch, a vehicle be situated in front of its points, or approaches these within a
certain distance, the arrangement is such that the switchman at the central station
is no longer able to reverse the said switch; this is effected as follows:-
From the leads of the two insulated commutator brushes and there are
branched off two leads which are connected with the two lengths of rail w in
front of the switch, and which leads are provided with suitable resistances as
shewn.
These rails are insulated from the rest of the line and must not be connected to
cach other by a conducting connection. If now they are put in conducting con-
nections by means of a vehicle standing upon them, a current will circulate through
the conductors as indicated by the arrows in Fig. 2 and the armature will be
attracted by its electro magnet. The stopping bar e will thus be pushed forward
and will consequently prevent the movement of the double contact switch a as long
as the vehicle is situated in front of the points.
At the same time the indicator disc connected to the armature will indicate
such stoppage. It will be seen from the connections that if the vehicle touches the
insulated rails at the moment when the railway switch is being reversed, the latter
will not be stopped half way, there being nothing to prevent it from completing its
motion.
a
The insulated rails have connected to them two other conductors which lead to
an order signalling apparatus D situated near the railway switch. When this order
signalling apparatus is reversed, no matter from which side, there occurs
momentary short circuit of the conductors connected to the electromagnet. The
armature is attracted, but in consequence of its inertia the momentary current
is not sufficient to bring it up to the poles of the electromagnet b, and, as above
described, the stud f engages with the notch of the catch after the current has

page_text: ceased, as shewn at Fig. 3. This middle position of the indicator disc of
armature b' serves as a signal to the switchman at the central station from the
shunters to reverse the railway switch. On this being done, the armature is first
completely attracted and is then withdrawn, whereby the locking action of the
catch & ceases, and the disc moves to the end position.
On setting the railway switch in the opposite position to that shewn at Fig. 1 the
following operations take place.
The double contact switch a is first brought into the position in which it lies on
the contacts 2 and 3, as shewn at Fig. 4; the lead to the electromagnet c is thus
interrupted and the armature c¹ is drawn away therefrom by its spring, and its
indicator disc is correspondingly moved from the position it occupied. The
armature c¹ also moves the contact switch d from the contacts 4 and 5 on to 6 and 7
thereby breaking the semaphore signal circuit E connected to 4. As shewn by
the arrows in Fig. 4, the full working current now passes through the windings of
the electro motor field magnets so as to set this in motion. At the same moment
that this current takes place, the armature his attracted by the poles p p.
The cam groove on the revolving disc n brings the lever u, shortly before the
termination of the unlocking phase, into the middle position in which it remains
until the switch is reversed. The lever t which will have come in contact with
stop i, will remain in position while the disc continues to revolve. .
No alteration of the position of the brushes consequently takes place on the
movement of the lever u into the middle position.
When the disc u has moved gradually into the relocking position, the lever u will
be moved by its cam groove beyond the middle position. In consequence hereof
the strained tumbling spring will throw the levert over, whereby the studs Z Z³
will raise the brushes and off the commutator and will allow the brushes v¹
and to come in contact therewith as shewn at Fig. 5.
In the circuit of the applied brush there is now included the comparatively
large resistance of the windings of the electro magnet c, so that the electro motor
will again remain at rest, while the circuit through which the working current
formerly flowed is broken by the raising of the brush v. The electromagnet c.
being now excited by the current, it attracts the armature c' with its indicator disc;
the contact switch d is thereby brought on the contacts 4 and 5 again, thus
re-establishing the interrupted signal circuit E.
On the switch being again reversed, that is to say, when the double contact
switch a is brought on contacts 1 and 2, the same operations as above described
take place; the working current then passes through the brushes v' and ' so that
the motor armature is made to revolve in the contrary direction.
If the points are forced open by a vehicle, for example in the position shewn at
Fig. 4, then by the forcible rotation of the disc n the pins will be sheared
(n being stationary) and the lever u will be moved into the middle position,
beyond which it cannot pass, as according to the direction of rotation of the
disc n, the stop y' or y² on the disc in coming in contact with the projection
of the stationary toothed ring n', will prevent the further motion of the disc,
as shewn at Fig. 6. As in this case the armature with its stops is not
attracted, the stud ³ of lever will at the commencement of the motion of
lever u, raise the brush out of contact, as the lever t will only be stopped
in its tumbling action by the stop 3. By such raising of a third brush, the
indicating current passing through the windings of electromagnet c will be
interrupted, the armature c¹ with its indicator disc will be drawn off by its spring
and the circuit E leading to a semaphore or other signal will be broken.
From the foregoing description it will be seen that by means of the armature c¹
and its disc an indication will always be given at the central station of the proper
locking of a switch in position, whether a circuit is broken, and whether the
electromotor is in proper order; and that the armature and its disc will also
indicate whether vehicles are in front of the points, and whether an order for
reversal has been given.

page_text: a² are windows in the screen behind which the indicator discs work, so as to
show their different positions.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:-
1. In apparatus for working railway switches by means of electrical energy
wherein the putting in and out of action and reversal of the motion of the electro-
motor is effected by the inclusion and exclusion of resistances in combination with
three conductors, providing the electromotor with two pairs of commutator brushes
so arranged that the stopping of the motor is effected by throwing the one pair of
brushes out of contact and the second pair into contact, while at the same time such
a resistance is included in the circuit as will prevent the current then passing, from
actuating the motor and will also cause an indicator to be actuated substantially as
described.
2. In apparatus for working railway switches such as is referred to in the
preceding claim, a reversing device for the electromotor wherein a lever u, actuated
by the disc n that works the railway switch is made to effect the reversal of the
commutator brushes for stopping the motor by means of a lever t, which, when the
apparatus works in the normal condition, is limited in its motion by stops on an
armature h attracted by the field magnets of the motor, the movement of the levert
being effected by a tumbling device only after the switch has been locked in
position, while when the switch is forced open by a passing train, the motor being
at rest, the lever t is moved beyond the said limits by the lever u and is thereby
made to throw one of the brushes, that are in action for the time being, out of
contact, so as to interrupt the current flowing through the motor and thereby to
cause an indicator to be actuated at the central station, substantially as described.
3. In combination with the apparatus for working railway switches referred to
in the preceding claims, the use in front of the points of insulated lengths of rail
which are so connected by branch conductors with the circuits leading from the
apparatus at the central station to the electromotor that when a vehicle is situated
on the said insulated rails, it completes the said branch circuit and thereby causes
a current to actuate a locking device and indicator at the central station so as to
prevent the operator from moving the switches of the actuating apparatus until the
vehicle or train has passed away, substantially as described.
4. In combination with the insulated rails and branch circuit referred to in the
third claim, the use of a second branch circuit connected through the insulated
rails to the first named branch circuit and to a contact switch such as D situated at
the points whereby a momentary current sent through the electromagnet 6 of the
indicator apparatus at the central station will put a locking device fk in action
that will cause the armature and the indicator semaphore connected therewith to
be held in an intermediate position for the purpose of signalling from the points to
the central station substantially as described.
5. In combination with the electromagnet c and armature c¹ of the apparatus at
the central station the use of a switch d which when the armature c¹ is attracted by
its electromagnet is moved thereby so as to close the circuit of a semaphore or
other signal on the line but which is moved so as to break that circuit when the
electromagnet c has no current passing through it, substantially as described.
6. Apparatus for working railway switches by means of electrical energy,
combined and operating as herein described with reference to the accompanying
drawings.
Dated this 21st day of August 1801
ABEL & IMRAY,
Agents for Applicants.