Improvements in or relating to Electrical Signal Apparatus for Indicating the Position of Railway Switches or Points.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Improvements in or relating to Electrical Signal Apparatus for
Indicating the Position of Railway Switches or Points.
A communication by PAUL SCHWENKE, of Zerbst, in the Empire of Germany.
I, WILLIAM PHILLIPS THOMPSON F.C.S., M.I.M.E., of the Agency for
Foreign Patent Solicitors, 6 Lord Street, Liverpool and 6 Bank Street,
Manchester, both in the County of Lancaster and 323 High Holborn in the
County of Middlesex, Civil 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 invention relates to apparatus for indicating exactly the position of railway
switches or points, and is composed of the following parts, to wit, the electric
apparatus for indicating or registering the position of facing points (Figures 1 to 14
inclusive of the accompanying drawings) and the apparatus for producing the
contact at the switch.
1) Figures 1, 4 and 7 show the principal apparatus in its different positions.
The armature a (Figure 4), pivotted on its axis d, is attracted by the electro-
magnets when the electric current flows through them. At the same time,
the projection of armature a¹ prevents the armature a of the magnet 6 from
falling back (Figure 4).
As soon, however, as the current flows through the magnets b', the armature a¹
is attracted and a falls down, drawn by a spring g, and its nosef engages the
armature a¹ and prevents it from returning to its former position (Figure 1).
On the axis d is fixed a small toothed wheel i, which engages a pinion on
the axis upon which is fixed the pointer (Figures 10, 11, 12). The motion
of the armatures is thus transferred to the pointer which indicates, on a dial, if
the switch is set for the through road or for the branch.
CC (Sheets 1 and 3) are the switch tongues, and B B¹ the electric batteries.
For setting the principal apparatus, Figure 1, in communication with the switch,
two relays (Figures 3 and 3^) are placed above it.
These relays, which have a common battery, are in direct communication with
the switch. The relay (Figure 3) is in communication with the magnets
(Figure 1), and the relay (Figure 3^) is in communication with the magnets bb
(Figure 1).
As soon as the contact C¹ on the switch is made (Sheet 1) the current passes
through the bobbins 65 65 (Figure 3). The armature a³ is attracted, and, by
means of contact screws and wires, the circuit of the battery B is closed
(Figure 1). The current from B flows through the screw 9 which has a
metallic communication with armature a'.
At o, the current is transferred to the interrupting spring n, whence it goes
into the bobbins 6b which are in communication with the terminal s'. From s¹,
the current passes through armature a into the metallic frame of the relay, and
from thence by wire t to the frame of the other relay, and from q' to the battery B.
Thus the armature a is attracted by bobbins bb (Figure 4).
If the other contact C (Figures 4-6) Sheet 2, is made, the relay, Figure 6,
comes into operation and the circuit is closed in the same manner for the
bobbins 6 65. Armature a is attracted by the electro-magnets and also
armature a¹ by bb. Thus the armature a takes the position indicated by
Figure 1 by means of the spiral spring 9. When the armature a is in the
positions shown in Figures 1 and 4, the pointer, Figures 10 and 11, indicated
on a dial the position of the switch if it is set for the through road or for the
branch, as above described.

page_text: Now it may happen that, by some accident, the contact is made at neither C
nor C¹, as represented on Sheet 3, and the current does not pass through
either of the relays. In this case, a special apparatus (Figures 2, 5 and 8) is
arranged.
This apparatus, represented by Figures 13 and 14, in perspective, is placed
directly above the principal apparatus and below the relays. It has also two
pairs of magnets 6 and 6 with their armatures a³ and a³. The armature a³,
which takes ordinarily the position indicated by Figures 2 and 5, swings round
a fulcrum d' on which is fixed a toothed wheel gearing with a second wheel h',
to which is attached an arm bearing a warning inscription.
•
The operation of this apparatus is as follows:-
If no contact at C or C¹ take place, the two armatures a¹ aª are raised by
the springs 9 (Figures 9 and 9*) and are pressed against the contact
screws u u. Now the intermediate apparatus, Figure 8, is placed with its
magnets in a closed circuit. The current coming from the battery B passes
at g' through the frame of the intermediate apparatus and through the
magnets By means of the screw u', the current passes to the armature a
of the relay, and is conducted by along wire_t to screw u and into the
second relay, and returns by 9' to the battery B. Thus the armature a² of
the intermediate apparatus is attracted (Figure 8) and swings to the right. The
toothed wheel on the axis d' rotates also to the right, and the pinion h¹
rotates in the opposite direction and brings the sign with the warning into the
position shown in Figures 12 and 14, thus covering the pointer of the dial.
When the armature a² is attracted, the armature a³ becomes free and, by
means of a spring_el (Figure 14), is raised and holds the armature a² in the
position shown in Figure 8 and closes the circuit through the bobbins b'.
If now the contact at C or C¹ is made, one of the armatures a² or a³ of the relays
will be attracted, and the current conducted through the bobbins b'. Armature a¹
is now attracted, and armature a, becoming free, falls down, by means of its
spring g, and the sign is lifted again, as shown by the Figures 10, 11 and 13.
For economising the electric current and the material of the batteries, the
armatures are furnished with interrupting springs n and n', by which the current
is interrupted as soon as the different armatures are attracted and fastened in
their positions by the means above described.
2) The apparatus for producing the contact at the switch is as follows:-
A small glass tube, Figure 15, closed hermetically at both ends and com-
pletely void of air, contains a little mercury . Two wires c and c' of platinum
are fixed in the glass. These wires are the continuation of the above mentioned
conductors. The glass tube is placed in an oblique position in a wooden box d³
(Figure 16); the end containing the wires being placed higher than the other
end containing the mercury. A box h of iron or other metal is furnished with
a movable bottom turning on its axis. Upon this bottom the box d is placed,
Figure 16, showing its ordinary position. The axis f¹ has, on the other side, a
nose i
This apparatus is placed on the sleeper, the nose being placed opposite to
the switch tongue. A piece of flat iron m¹ is fixed on the switch tongue sliding
under the rail 1. As soon
as the tongue is drawn near the rail 1, an
adjustable screw n³ presses against the edge of and causes bottom, with the
box d², to be tilted (Figure 18). By this motion, the tube a' is also tilted, and
the mercury rolls to the other end and touches the two wires c c. Thus the
electric circuit is closed and the above described signal may be operated.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, as communicated to
me by my foreign correspondent, I declare that what I claim is :-
1. The use, in combination with an electric apparatus for indicating the position
of railway facing points or switches, of devices substantially as described for

page_text: making or breaking electrical contact at the switch and closing or opening the
circuit, whereby an indication of the portion of the points (whether for the
through road or for the branch) can be obtained.
2. In combination with the device set forth in Claim 1 of an appliance for
indicating the position of the switch, consisting of the armature a, swinging on
an axis d, the electro-magnets 66¹ for attracting said armature, and a dial and
pointer, the whole arranged in such a manner that the swinging motion of the
armature is transferred to the pointer on the dial, substantially as described.
3. The use, in combination with apparatus for indicating the position of facing
points or switches of relays placed above the indicating apparatus, and through
which the current must pass before it reaches the said indicator, substantially
as described.
4. The application of interrupting springs on the electro-magnets for economising
the electric current and the material of the batteries, substantially as described.
5. The general combined arrangement or construction of parts substantially as
described.
Dated this 11th day of February 1892.
WM. P. THOMPSON & Co.,
Agents for the Applicant.
WM. P. THOMPSON & Co.,
Agents for the Applicant.