Improvements in Apparatus for the Electrical Working of Railway Points and Signale.
Year: 1899

page_text: Date of Application, 6th July, 1899-Accepted, 9th Sept., 1899
COMPLETE SPECIFICATION.
Improvements in Apparatus for the Electrical Working of Railway
Points and Signale.
We, SIEMENS BROTHERS & Co. LIMITED, of 12, Queen Anne's Gate, West-
minster, S.W., Electrical Engineers, do hereby declare the nature of this
invention (as communicated to us from abroad by Siemens & Halske Aktien
Gesellschaft, of Markgrafen Strasse No. 94, Berlin, S.W., Electrical Engineers),
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 the electric working of railway points
and signals by means of which, with simple apparatus and use of the minimum
possible number of leads, the two requisites for safe and rapid working of the
moving parts are attained, namely the reliable control of the points and signal
setting mechanism and the limitation as far as possible of useless action of the
motor.
There are two kinds of electrical actuating devices for this purpose namely
that in which a reversal of the movement is possible in every position of the
actuating mechanism, and that in which the motor can be reversed only at the
end of its work in the one direction.
In the latter kind the disconnection of the lead used for the one direction of
rotation of the motor and the connecting up of the other lead take place at the
end of the work of the motor. The switch arrangements for this case are shewn
diagrammatically in Figs. 1 to 3 of the accompanying drawings.
At the setting mechanism there are two switches a and b, coupled together,
one of which is connected with the one pole of a source of electrical energy such
as a battery c and the other with the second pole. By means of this hand switch
the leads and e respectively can be switched on to the one or the other pole
of the battery. The switch f,on the actuating device serves to connect the motor
automatically, as in the manner described in the Specification to Patent 22570/93,
to either of the leads d or e. Lead is the common return wire. In the lead h
is included the electro-magnet i which in the known manner, serves to indicate
to the operator the working condition of the setting device.
In Fig. 1 all the parts are in the position when the motor is at rest; Fig. 2.
shews their position when the motor is in movement. In both cases there are
two closed circuits. In the position of rest the electrical connection is: negative
pole of the battery, switch b, lead d, contact m, motor, lead g, negative pole of the
battery, the motor is short circuited and cannot be set in motion by any
accidental accession of current. At the same time the circuit of the indicator
namely positive pole, switch a, lead e, .contacts and k, lead' h, electromagneti,
negative pole, is closed. The armature of the electromagnet is attracted and
indicates the proper position of the setting mechanism. In this circuit are
included the necessary contacts, for the control of the close setting of the points
and their locking devices, together with the corresponding indicators.
רנס...

page_text: In the same circuit there may also be arranged a contact which when the points
are forced open, interrupts the control current and effects the necessary block
in the setting mechanism. When the switches a and b are moved over from the
position shewn in Fig. 1 two new closed circuits are formed, as shewn in Fig. 2,
namely (1) positive pole, switch a, lead d, motor, lead g, negative pole, and
(2) negative pole, switch b, lead e, contacts k and 1, lead h, electromagnet i,
negative pole. The motor, therefore, receives current and moves the setting
mechanism while the electromagnet is in a short circuit. Current not being
supplied to the magnet in this position of the switches an incorrect indication
cannot occur.
At the end of the work of the motor the latter is automatically cut out by the
switch. In this way the working current is interrupted and the motor short
circuited over leads e and g so that it is brought to rest in a very short time
by the generator brake, which, as is known, is brought into play by this short
circuit. The indicator maguet is now again in a second circuit and indicates
that the setting of the points is finished, as at Fig. 3.
•
By turning back the switches of the setting mechanism the motor is set in
rotation, in the known manner, in a direction the reverso of the former one for
the return motion. The same course as has been described above is then
followed. In each phase of movement there is a working current circuit and a
second circuit connection, short circuited in itself, in which the motor and the
indicator inagnet are alternately included.
In order that the indicator may not receive current otherwise than in the
prescribed manner, during the time that the setting mechanism is in the position
of rest, one battery pole is in this case connected to earth, in the same way as in
the arrangement described in German Patent No. 83851 (English Patent
11025/95 so that the indicator circuit may never be untimely closed by some
fortuitous earth contact. As shown in the drawing, that pole to which the return
iead is attached may be connected to earth. Such an arrangement has the
advantage over that formerly used that a special return lead either may be
entirely done away with, or may be of considerably smaller cross section than those
hitherto used.
For a setting mechanism which may be reversed at any phase of the movement
(as, for example, is described in German Patent No. 95478) the arrangement
described above needs alteration in one point. In this case the connecting up
of the lead for the return movement of the motor takes place at the beginning
of the movement and the disconnection of the other leads shortly before the end
of the movement, so that one lead alone is in circuit with the motor at the end of
the movement (see Fig. 4), while both leads are in the motor circuit during the
movement (see Fig. 5).
For completing this switching device only one contact o (Figs: 4 to 6) is
provided which breaks the connection between switch 6 and the negative pole of
the battery so long as both motor leads are connected at the same time with the
motor. If this contact were not provided there would exist (as shewn in
Fig. 5) in addition to the working current, positive pole, switch a, lead d, motor,
leadh, negative pole, a shunt current; positive pole lead d, contacts m and I,
lead e, negative pole, which under certain conditious may give rise to disturbance.
The influence of this shunt current might however be made harmless by intro-
ducing appropriate resistances.
The contact o, as shewn in Figs. 4 and 5, may be attached directly to the
armature of the indicator electromagnet since this is released when the switch is
turned over and is only attracted again when the setting of the points is com-
pleted. It may, however, be so arranged that it is opened by force, independently
of the electromagnet which then only closes it again.
In Fig. 6 another arrangement of this contact is shewn, wherein it is coupled
with the motor switch f. It breaks the circuit between the switch band the
negative pole before the two leads and are connected by the switch f, and

page_text: only closes it again after the connection between these two leads is broken.
This arrangement does not otherwise differ from that described above.
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
1. Apparatus for the electrical control of railway points and signals in which
the disconnection of the lead for the rotation of the motor in the one direction
and the connecting up of the lead for its rotation in the other direction are
effected simultaneously the motor being short circuited at the end of the move-
ment, such apparatus consisting of switches (a b) at the setting mechanism and
a switch fat the actuating apparatus which switches are connected with the
motor by four leads (de g h) in such manner that there are always two closed
circuits, in one of which a current flows while the other is short circuited; the
motor being in the short circuit and the indicator electromagnet being in the
current carrying circuit when the motor is at rest, while on reversing for working
the motor, this is included in the current carrying circuit and the indicator
electromagnet in the short circuit, substantially as described!
2. In apparatus for the electrical working of railway points and signals such as
is referred to in the first claim the modification wherein the connection of the
contact b, with the negative (earth) pole is closed only at the final position
of the working device but is open during the setting of the points or signals,
the necessary interruption being made by means of a contact o which is actuated
in connection with the indicating device either directly by the working apparatus
or indirectly by the point or signal lever, substantially as described:
Dated this 6th day of July 1899.
ABEL & IMRAY,
Agents for the Applicants.