Improvements in Electrical Signalling Apparatus for Railways.
Year: 1898

page_text: Date of Application, 23rd Sept., 1898-Accepted, 23rd Sept., 1899
COMPLETE SPECIFICATION.
Improvements in Electrical Signalling Apparatus for Railways.
I, FRIEDRICH PEGELOW, of 17, Holdutcza, Budapest, in the Kingdom of Hun-
gary, 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 object of this invention is to prevent collisions between two vehicles
approaching each other upon rails, by means of electrical sound, light or other
signals or alarms which are adapted to be arranged directly upon the platform
or stand of the driver of the vehicle in order to give warning when his vehicle
has approached within any pre-determined distance of another vehicle (upon the
same rails) so that he may be caused to take the necessary precautions for avoid-
ing an accident.
The characteristic features of the invention are the simplicity with which it may
be carried into effect and the certainty of its action both by day and night. The
invention is illustrated in the accompanying drawing in which:-
Fig. 1 shows the source of electricity a arranged upon the vehicle, the alarm
signal b and a switch board A together with the current conducting parts or
rolling contacts DE E¹, of which two (either D E or D E¹ according to the
position of the vehicle) complete the electrical circuit; the positive and negative
conductors H-H₁ F G respectively connecting the approaching vehicles one with
the other are also shown.
Fig. 2 shows the arrangement of the positive and negative conductors which is
such that one of the conductors is provided by the track (ie. rails) H H¹ itself,
one side of which, either H or H¹, consists of conducting rails connected one with
the other, whilst the other conductor is formed by two rails F G of any desired
cross-section which run parallel with and are insulated from each other. The
single lengths of such latter rails are equal to or more than the permissible nearness
of approach of two vehicles one to the other, and are so arranged that the ends
of any two rails lying end to end are situated at the middle point of the length
of the opposite rail that is to say at the separating interval above referred to.
This serves to fix the interval of approach and also to warn the driver of the
presence of danger at twice the minimum distance in many cases.
Fig. 3 shows the switch board A with its two indicators J and J¹ the terminals
KZ B C B and contacts 1 to 5 and 7 to 10. 6 is a hole for the plug d.
Fig. 4 illustrates a direction indicator with its two insulated contact. plugs.
Fig. 5 shows the path of the closed electrical circuit of two approaching vehicles,
that is to say, of M towards N, and L towards M. The operation of the apparatus
is produced owing to the fact that the two poles of the source of electricity.a
are connected with the signal 6 inserted between them by means of the ter-
minals Z and K, and the conducting rails F G H H¹ by means of suitable con-
tacts DE E¹, and binding screws BC B¹ with the switch board; according to the
position of the vehicle either the contact E or E¹ rests upon the conductor F G
and by means of the indicator J which is pivotally mounted at f and provided
with two insulated plugs c d contact is also made through the terminals 7 and 8

page_text: or 9 and 10. If the vehicle is travelling either backwards or forwards the
plugs cd of the second indicator J¹ which is pivoted at e are brought into contact
with either the contacts 1 and 2 or 3 and 4 according to the direction of travel
thereby closing the circuit. If two trains L and M for example, travelling in
opposite directions are thus arranged and resting their rolling contacts E or E¹
upon the same length of the common conducting rails F G the current will be
constantly closed (as shown in Fig. 5) and both alarm signals will act so that
--the-respective-drivers may-if desired-communicate-one-with-the-other-by-means
of the telephone or telegraph.
"
If the vehicle is not in motion the indicator J¹ is placed upon the "stop
division 5-6. In this case contact from H to E or E is formed through the
contact 5, and a second vehicle approaching from either direction will receive a
warning of the presence of danger.
When the vehicle M moves towards the vehicle L the indicator J¹ on M, (if,
as before described, adjusted according to the direction of motion,) closes the
contacts 1 and 2; the indicator J is moved towards the side on which the rails
FG, are arranged, and making contact at 7 and 8, connects the negative pole Z,
through roller E and the rails F G, and the positive pole K is connected with
the wheels D and rails H H¹.
On the vehicle L the indicators Ji and J are adjusted under similar conditions
as on M, that is to say, the indicator J¹ closes the contacts 1 and 2, whereas the
indicator J closes the circuit at 9 and 10, thus connecting the negative pole Z
with the wheels 1) and the rails H, H¹ and the positive pole K is connected through
the roller E¹ with the rails F G. The contacts D and E, and D and E¹ of the
approaching vehicles are respectively charged with electricity of opposite character.
When now, the rollers E and E come into contact with the same length of rails
FG, a continuous current passes which actuates the signalling apparatus. The
circuit is completed through F G, E, B, 7, 2, Z, a, b, K, 1, 8, C, D, of vehicle M,
to rails H H, thence to D, C, 9, 2, Z, a, b, K, 1, 10, B¹, E', in vehicle L, back
to rail FG, actuating the signal in both vehicles.
Supposing the vehicle M. moves towards N (N moving backwards), the position
of the indicator on M is the same as in the former case; on N, however, the
indicator being placed in the direction of travel, contact must be made at 3
and 4, whereas by means of the indicator J contact is made at 7 and 8, so that
the roller E and rails F G, become positively, and the wheels D and rails H H
negatively electric, and upon the two vehicles approaching near enough the circuit
is completed through F G, E, B, 7, 2, Z, a, b, K, 1, 8, C, D, of vehicle M, to
rails HH, thence to D, C, 8, 3, Z, a, b, K, 4, 7, B, E, in vehicle N back to rail FG,
actuating the signal in both vehicles.
When a vehicle stands still, the indicator J¹ must be placed on 5 and 6 by which
means a circuit is closed at 5. If, now, an approaching vehicle, comes on to the
same length of rails FG, the current from such vehicle passes through the
rollers E or E of the non-moving vehicle and arrives through contact stop 5,
rails D and rails H H at the point from which it started, actuating a signal in
the moving vehicle but on the non-moving vehicle no signal is actuated.
A telegraphic or telephonic communication between the two vehicles can be
effected as soon as the signals have been actuated and the vehicles brought to a
standstill, by switching off the signals and switching on a telegraphic or telephonic
apparatus so that the drivers can communicate with each other, for which purpose
the rails F G and H H¹ can be used as conductors.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is-
1. In electrical alarms for vehicles running upon rails, adapted to be arranged
directly upon the driver's platform, for the purpose of preventing collisions--a
system of conducting rails of any desired cross-section running parallel with and

page_text: insulated from each other the lengths of such rails being equal to or more than
the permissible nearness of approach of two vehicles one to the other the rails
being so arranged that the ends of any two rails lying end to end are situated
at the middle point of the length of the adjoining rail so that vehicles over-stepping
such permissible separating distance receive a warning substantially in the man-
ner and by the means herein before described.
2. In an electrical alarm of the character claimed above-the arrangement
and combination therewith of switches for the purpose of so connecting an alarm
signal and current conductors F G H H¹ by means of rolling contacts E E' D
that by placing one indicator J in a manner corresponding to the side upon which
the conducting rail F G is situated and the other indicator J¹ so as to correspond
to the direction of travel contacts are made whereby vehicles which over-step the
permissible distance of approach may by means of the system of current con-
ductors claimed in Claim 1 receive warning of danger owing to the operation
of the alarm signal substantially in the manner hereinbefore set forth.
3. The improved electric alarm apparatus arranged combined and operating
substantially as and for the purposes herein before described and illustrated in
the drawings hereunto annexed.
TONGUE & BIRKBECK,
Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the 'Applicant.