Improved Apparatus for Working Railway Switches by Means of Electrical Energy.
Year: 1893

page_text: 1893
Date of Application, 7th Mar.,
Complete Specification Left, 25th Nov., 1893-Accepted, 30th Dec.,
1893
PROVISIONAL SPECIFICATION.
[Communicated from abroad by Messrs. SIEMENS AND HALSKE, Electrical
Engineers, of No. 94, Markgrafenstrasse, Berlin, in the Empire of Germany.]
Improved Apparatus for Working Railway Switches by Means of
Electrical Energy.
We, SIEMENS BROTHERS & Co., LIMITED, Electrical Engineers, of
No. 12 Queen Anne's Gate, Westminster, in the County of Middlesex, 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 electro motor,
and in which a control apparatus is made to indicate to the pointsman the proper
closing of the points as also the forcing open of the points by a train, and any
irregular working of the apparatus such as interruption of the electric circuit.
According to this invention the electro motor coupled with the switch apparatus
is connected with the apparatus at the central station and a current generator by
means of contacts and three conductors, of which one serves for conveying the
current for rotating the motor in the one direction, a second one for conveying the
current for rotating the motor in the contrary direction, while the third conductor
always serves for the return current, the supply conductor which is, for the
time being, unoccupied, being utilised for actuating the control or indicating
apparatus.
The indicating apparatus has three functions to fulfil, namely, first, any
disturbance in the conductor or other parts of the apparatus is made known by the
interruption of a static current, and consequent actuation of a signal; secondly,
on opening the points of the switch a signalling circuit is interrupted, and thirdly
the correct closing of the points is indicated by the sounding of a third signal.
The said apparatus is shewn diagrammatically on the accompanying drawings.
Figs. 1 to 4 shew the positions of the several contact levers and armatures
during the reversing of a switch from one position to another....
For the above named purposes the apparatus for working the switches consists
of three parts A, B, and C. The part marked, A. constitutes the switch-setting
apparatus at the central station. It has reversing contacts a by means of which
the railway switch can be reversed from the central station; also two pairs of
electro magnets be and de, with thin wire windings, two and two being connected
diagonally, so that an armature that can oscillate between them, and carries a
signal disc, is thereby brought into opposite angular positions according as the
current is made to pass through b c or de. On the cessation of the current the
armature and disc assumes by gravity a middle position.
The apparatus A also coutains an electro magnet g having thick wire windings
the armature of which in combination with a reversing switch connects the
contacts K2 and K³ when no current is passing.
B is the apparatus which has to effect the movement of the switch; it consists
of a motor engine A' coupled with a screw spindle, a reversing switch G¹ and a
circuit breaker B¹, as also an apparatus D' for setting and locking the points, of
known construction.
C is the source of current.
The course of the current with the normal locked position of the points will be
readily understood from the arrows in Figs. 1 and 4.
In consequence of the great resistance of the coils of be and de, only a com-
paratively small current passes into the circuit when connected up as shewn.

page_text: The armature f with its signal disc is in this case attracted by the electro
magnets bc or de, while the motor A' remains at rest.
The weak current continuously circulating in the circuit has for its object to
serve as a control or indicating current. If for example one of the commutator
brushes of the motor did not make contact, &c., the circuit being broken thereby,
the armature would cease to be attracted and the pointsman would be thereby
duly advised of the circumstance.
If the points are to be moved from the position shewn in Fig. 1 into that shewn
in Fig. 4, the following takes place. The pointsman brings the current reverser a
into the position shewn at Figs. 2, 3 and 4.
As the current now passes through the electro magnet g, its armature is attracted
and the circuit 3 leading to the coils of bc and de is interrupted, so that the
armature with signal disc will assume the middle position. The motor engine
at B being set in motion by the above connections of the circuit, the points will be
moved over by the rotation of the screw spindle. Shortly before the unlocking of
the points is effected by the movement of the nut, the circuit breaker B₁ will be
moved into the position shewn at Fig. 2 by the projection on the end of the bar
which is fixed to and travels with the nut on the screw spindle.
The reversing switch G¹ whose reversing spring will have become more compressed,
by such motion of the bar t, still remains in its original position.
On the points now moving over into the position at Fig. 3, which also shews the
commencement of the locking, the circuit breaker B will have returned to its
original middle position and the reversing switch G will, on a slight further motion
of the bar t, be reversed by the action of the compressed reversing spring. This
position is shewn at Fig. 4. The circuit 2 in which no resistance is included will
have been broken by the reversal of the points, and the circuit 1 which is subject
to the resistance of the coils of de will have been closed. At the same time the
electro-magnet 9 loses its current, and its armature will consequently, be moved
back into the middle position by its spring, while the armature with its signal disc
is attracted by the electromagnet de. The points are now locked in the opposite
position to that of Fig. 1.
The same steps take place when the points are to be again reversed, only in this
case, as shewn by the connections of the circuits, the motor A' will be made to
revolve in the contrary direction.
From the above described regular action of the apparatus in setting the points in
one position or the other, it will be seen that the circuit breaker BI exercises no
specific function, being simply actuated without effecting any result. If on the
other hand a locked switch be forced open by a passing train, the connecting rod of
the points, together with the bar t will be forcibly separated from the nut on the
screw spindle by the fracture of the connecting pin, as shewn at Fig. 5, whereupon
the bar t, in its motion, will move over the circuit breaker B' in the one direction
or the other (according to the direction in which the points are forced over) until
it makes a contact. In this case the points do not become locked, the motion of
the rod t being smaller than in the regular reversal of the points, and consequently
reversing switch G' will remain in its former position, its reversing spring being
only partially compressed. A current can now pass through electro magnet g
causing the armature to be attracted and the contact piece connected therewith
will consequently break the circuit 3 leading to the electro magnets be and de; as
by this means the control current is intercepted, the armature and its signal disc
will assume the middle position. In like manner the circuit of the field magnets of
the motor will be broken.
From the position assumed by the signal disc, the pointsman will now be apprised
of the fact that the switch is out of order.
Dated this 6th day of March 1893.
ABEL & IMRAY,
Agents for the Applicants.

page_text: COMPLETE SPECIFICATION.
Improved Apparatus for Working Railway Switches by Means of
Electrical Energy.
We, SIEMENS BROTHERS & Co., LIMITED, Electrical Engineers, of No. 12,
Queen Anne's Gate, Westminster in the County of Middlesex, 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 :-
This invention relates to apparatus for working switches on railways wherein the
setting and locking of the switches is effected by means of an electro motor and in
which a control apparatus is made to indicate to the pointsman the proper closing
of the points as also the forcing open of the points by a train, and any irregular
working of the apparatus such as interruption of the electric circuit.
According to this invention the electro motor coupled with the switch apparatus
is connected with the apparatus at the central station and a current generator by
means of contacts and three conductors, of which one serves for conveying the
current for rotating the motor in the one direction, a second one for conveying the
current for rotating the motor in the contrary direction, while the third conductor
always serves for the return current, the supply conductor which is, for the
time being unoccupied, being utilised for actuating the control or indicating
apparatus.
The indicating apparatus has three functions to fulfil, namely, first, any
disturbance in the conductor or other parts of the apparatus is made known by the
interruption of a closed circuit current, and consequent actuation of a signal;
secondly, on opening the points of the switch, a signalling circuit is interrupted, and
thirdly the correct closing of the points is indicated by the sounding of a third
signal. The said apparatus is shewn diagrammatically on the drawings accom-
panying our Provisional Specification. Figs 1 to 4 shew the positions of the
several contact levers and armatures during the reversing of a switch from one
position to another..
For the above named purposes the apparatus for working the switches consists
of three parts A B and C.. The part marked A constitutes the switch setting
apparatus at the central station. It has reversing contacts a by means of which
the railway switch can be reversed from the central station; also two pairs of
electro magnets be and de, with thin wire windings, two and two being connected
diagonally, so that an armature f that can oscillate between them and carries a
signal disc is thereby brought into opposite angular positions according as the
current is made to pass through b c or de.
On the cessation of the current the
armature and disc assumes by gravity a middle position.
The apparatus A also contains an electro magnet y having thick wire windings
the armature of which in combination with a reversing switch connects the
contacts K and K³ when no current is passing.
B is the apparatus which has to effect the movement of the switch; it consists of
an electric motor A coupled with a screw spindle, a reversing switch G¹ and a
circuit breaker B' as also an apparatus S for setting and locking the points, of
known construction.
C is the source of current.
The course of the current with the normal locked position of the points will
be readily understood from the arrows in Figs. 1 and 4.
In consequence of the great resistance of the coils of b c and d e, only a
comparatively small current passes into the circuit when the connections are such
as shewn.
:
The armature with its signal disc is in this case attracted by the electro
magnets bc or d e, while the motor A' remains at rest.
The weak current continuously circulating in the circuit has for its object to

page_text: serve as a control or indicating current. If for example one of the commutator
brushes of the motor did not make contact &c., the circuit being broken thereby,
the armature would cease to be attracted and the pointsman would be thereby
duly advised of the circumstance.
If the points are to be moved from the position shewn in Fig. 1 into that shewn
in Fig. 4 the following takes place. The pointsman brings the current reverser a
into the position shewn at Figs. 2, 3 and 4.
As the current now passes through the electro magnet g its armature is attracted
and the circuit 3 leading to the coils of c and d e is interrupted, so that the
armature with signal disc will assume the middle position. The motor at B being
set in motion by the above connections of the circuit, the points will be moved over
by the rotation of the screw spindle. Shortly before the unlocking of the points is
effected by the movement of the nut, the circuit breaker B₁ will be moved into the
position shewn at Fig. 2 by the projection on the end of the bar t which is fixed to
and travels with the nut on the screw spindle.
The reversing switch G' whose reversing spring will have become more
compressed by such motion of the bar still remains in its original position.
On the points, now moving over into the position at Fig. 3. which also shews the
commencement of the locking, the circuit breaker B will have returned to its
original middle position, and the reversing switch G' will, on a slight further
motion of the bar t, be reversed by the action of the compressed reversing spring.
This position is shewn at Fig. 4. The circuit 2 in which no resistance is included
will have been broken by the reversal of the points, and the circuit 1 which is
At the same
subject to the resistance of the coils of de will have been closed.
time the electro magnet y loses its current, and its armature will consequently be
moved back into the middle position by its spring, while the armature with its
signal disc is attracted by the electro magnet de. The points are now locked in
the opposite position to that of Fig. 1.
The same steps take place when the points are to be again reversed, only in this
case, as shewn by the connections of the circuits, the motor A¹ will be made to
revolve in the contrary direction.
From the above described regular action of the apparatus in setting the points
in one position or the other, it will be seen that the circuit breaker B₁ exercises no
specific function, being simply actuated without effecting any result. If on the
other hand a locked switch be forced open by a passing train, the connecting rod of
the points, together with the bart will be forcibly separated from the nut on the
screw spindle by the fracture of the connecting pin, as shewn at Fig. 5, whereupon
the bar t, in its motion, will move over the circuit breaker B' in the one direction
or the other (according to the direction in which the points are forced over) until
it makes a contact. In this case the points do not become locked, the motion of
the rod t being smaller than in the regular reversal of the points, and consequently
reversing switch G will remain in its former position, its reversing spring being
only partially compressed. A current can now pass through electro maguet g
causing the armature to be attracted and the contact piece connected therewith
will consequently break the circuit 3 leading to the electro magnets b c and de; as
by this means the control current is intercepted, the armature fand its signal disc
will assume the middle position. In like manner the circuit of the field magnets of
the motor will be broken.
From the position assumed by the signal disc, the pointsman will now be apprised
of the fact that the switch is out of order.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. Apparatus for working railway switches by electrical energy in which the
putting in and out of motion as also the change of direction of motion of the
actuating electro motor is effected by the inclusion and exclusion of a resistance

page_text: into and from the electrical circuit by the aid of three conductors, of which one
serves as the return conductor, the action being such that on operating at the
central station for the reversal of the switch, the resistance is cut out and the
electromotor is started, while on the completion of the reversal and locking of
the railway switch the motor is made to effect the reversal of a contact switch
whereby the main current is switched on to the conductor that before was idle,
under simultaneous re-introduction of the resistance, substantially as described.
2. The combination with the switch operating apparatus referred to in the
preceding claim, of an automatic control signalling apparatus at the central station,
arranged and operating substantially as herein described for indicating the condition
for the time being of the railway switch.
3. In combination with the switch operating apparatus referred to in the first
claim, the combination with the electromotor of a circuit breaker such as B¹
arranged between the two supply conductors and operating in such manner for
indicating the forcible opening of the railway switch, that the current reverser is
made to assume a middle position when the railway switch is locked in either of
the normal positions, but under other circunstances, makes contact with either of
the supply conductors, and thereby to break the connection between the field
magnet windings of the electromotor and the control signal apparatus referred to
in the second claim, substantially as described.
Dated this 25th day of November 1893.
ABEL & IMRAY,
Agents for the Applicants.