Intercommunication between Passengers and the Officials in Charge of Railway Trains.
Year: 1897

page_text: This Print is in accordance with the Original Specification as it stands after
Amendment (under Section 11 of the Patents, &c. Act, 1883) as required by
the decision of the Comptroller General of the 11th day of October, 1898.
Intercommunication between Passengers and the Officials in
Charge of Railway Trains.
I, WILLIAM EDWARD LANGDON, Electrical Engineer, Midland Railway, Derby,
do hereby declare the nature of this invention to be as follows:-
In an improved form of communication. between passengers and guards or other
officers in charge of railway trains.
To this end I provide within each compartment of each passenger vehicle and
passing along the length of the vehicle a communication cord or chain in such a
position that it shall be at certain points or if necessary throughout its length
accessible to the occupant of any such compartment and I so arrange this cord
that on its being pulled or its tension being increased it shall operate a switch
fixed in connection with one end thereof [or with either end] the opposite end of
the cord being made fast to the frame of the carriage.
The switch to which the cord is so attached is rigidly fixed to the framework of
the vehicle and is so arranged that on the cord operating it by causing a lever to
move an electric circuit is completed causing the bells in circuit therewith to be
set in motion and to continue to ring until the lever has been restored to its
position of rest.
In connection with the switch I also arrange an indicator so that on the switch
being operated the indicator may be discharged and thus indicate to the guard the
vehicle from which the alarm has been raised and so that the indicator shall also
on being discharged if necessary complete the electric circuit. The indicator once
discharged remains locked in that position until reinstated in its normal position
by the guard.

page_text: Intercommunication between Passengers and the Officials in
Charge of Railway Trains.
I, WILLIAM EDWARD LANGDON, Electrical Engineer, Midland Railway, Derby,
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 provide an improved form of communication
between passengers and guards or other officers in charge of railway trains.
To this end provide within each compartment, and passing along the length
of the vehicle, a communication cord, chain, or rod, preferably of wire, in such a
position that it shall, as shewn at A in Fig. 1, be readily accessible to passengers
occupying the compartment or vehicle. I connect this cord to the lever of an
indicator and electric commutator, Figs. II, III, IV, at any convenient point in
the route, or at the termination, of the cord so that, on a sufficient degree of tension
being exercised upon the cord, it shall cause the lever to move and release an
indicating disc, which, has for its purpose the indication of the position or vehicle
whence the communication is brought into use and which also I employ to
complete an electrical circuit and thereby cause the bells in the guard's vans or
other vehicles to ring and continue ringing until the disc is replaced. This disc
when once discharged, I maintain locked in the discharged position until it is
unlocked and restored by the guard. The form of coupling to connect. the
electrical arrangement of the one carriage to that of the adjoining vehicle is shewn
in Figs. V, VI and VII, and the circuit, or electrical disposition of the wires, in
Fig. VIII.
The
The disposition of the circuits is a well known one, but, in order to make the
action of other parts clear, I will explain shortly its action. A and B are two
wires passing throughout the train. Between these wires are arranged the bells
and batteries in the guards vans as shewn, the positive pole of each battery being
connected to B, and the negative, by way of the bell to A. or vice versa.
batteries are thus in contention, and, so long as they are sufficiently balanced, no
current will flow to operate the bells. Immediately, however, A and B are con-
nected, either by depressing the key o in the guard's van, or by connecting the
wires by the commutator at d, which may be regarded as a carriage operating the
communication, the balance will be disturbed and every battery so connected in
the train will complete its circuit by means of the connection so formed.
The operation then is this:-A passenger pulls the cord. The lever to which
it is attached is operated. The indicating disc is disclosed [thereby indicating the
vehicle or compartment in which the alarm is raised] and the connection d Fig. 8
formed, and the bells set ringing. The keys c may be operated for the purpose of
signalling between the officials of the train without regard to intermediate vehicles,
and, if required, the bell may be supplemented by a telephone.
Figs. II, III and IV illustrate the action of the commutator fixed within the
carriage, or compartment of a carriage. C, Fig. IV, is the lever to which the cord
is attached. This lever is centered at e and is provided with a slot m¹ to admit
of the presence of the pin . The pin e¹ is fixed in the rod A actuated and held
in the position shewn by the helical spring d and the socket pieces A¹ A". The
upper end of A is also slotted to receive one end of the lever Ġ which is centered
at g, Fig. II, and which carries a hook at its opposite end. This hook engages
with a corresponding hook gl fixed to the indicator disc M which is centered at o.
Also fixed upon, or forming part of, M, is an inclined spherical plane i, and

page_text: impinging upon it is a piston or plunger rod h actuated by a helical spring enclosed
in H. Fixed to the frame plate P are insulated standards carrying springs B B,
which, as shewn in Fig. IV, rest upon an insulated part of A. These springs are
connected to the circuit wires A, B, referred to under Fig. VIII. cc are platinized
or other electrical contacts. At m, Figs. III and IV, is shewn a detent or check
piece, the tendency of which, under the influence of the helical spring k, Fig. II,
is to engage with the projecting collar n, Fig. III, and which, when A is thrust
down by the movement of the lever C, engages with the collar non A provided for
that purpose and to hold the helical spring d in position as shewn in Fig. III,
until it is released by the insertion of a guard's key or other suitable device at /,
Fig. II, when the rod K, Fig. II, which carries the catch piece m can be turned
back, when the helical spring d, re-asserting its influence, restores the arrangement
to its normal condition as shewn in Fig. IV, after which the disc can be pressed
home and thus re-engage with G.
The action of this part is thus:-The lever C is moved. The rod A is depressed.
The two circuit wires A & B are brought into circuit as shewn at Fig.. III. The
lever G releases g' and the disc M flies out under the influence of h acting upon i;
thereby indicating to the officials in charge of the train the position from which
the communication has been brought into use. In this position the arrangement
remains locked, the current continuing to flow through the springs B and the
rod A, at c, until re-adjusted by the official in charge of the train.
With the object of preventing the two wires A and B being crossed when
connecting vehicles together I terminate the wires of each vehicle by means of a
connecting piece A, Fig. VI having a projection a and a recessed portion b, the
latter of which is fitted with two springs b¹ so that the projection of the one
part of the couping may engage with the springs of the recessed portion of the
other part of the coupling. This arrangement applies to each wire and to each
half of the coupling. Fig. VI represents a longitudinal section of the coupling
applicable to one wire only, that applicable to the other wire
is similarly shaped but arranged so that the projecting and recessed parts shall be
opposite in position to those in connection with the A wire, and efficiently insulated
therefrom.
Fig. VII is a front view of that end of the half of the coupling which connects
with the other half. The portion marked A is that applicable to, say, the A wire,
and the portion lettered B that applicable to the B wire, the projection a of the A
wire corresponds with that similarly lettered in Fig. VI, and the projection a¹ is
that corresponding with a but applicable to wire B. are the springs applicable
to the A wire, and cell those applicable to the B wire. The two portions or wires
are insulated at D. The springs b₁₁ and cll are as shewn in Fig. VI shaped,
and the projections a, a¹ are notched to correspond, so that, on the two parts of the
coupling being pressed together, the bent portion of the springs may engage with
the notches on the projections a a¹ for the double purpose of securing good contact
and holding the two portions of the coupling together until forcibly drawn apart.
The cover C is provided with a hook e at the bottom, and a horn fat the
opposite side. These are each arranged on one side of a line drawn centrally from
one side to the other of the device, so that, on the two halves of the coupling being fitted
together, the hook of the one being placed within that of the other as shewn in
Fig. V, the horn f will enter the recess g, Fig. VII, and the two parts will be
locked together, the wire A of the one vehicle being connected with the wire A of
the adjoining vehicle, and the wire B of the one with the wire B of the other, dis
an indiarubber washer provided to exclude moisture.
Fig. V is an external view of the coupling thus arranged when joined together.
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:-
:-
First. The employment within a railway vehicle of a cord or other like means

page_text: for mechanically operating an electrical commutator, with or without an indicator,
for the purposes, herein described and set forth.
Secondly. The employment in combination with such an arrangement as is
claimed in Claim 1 of an electrical coupling so arranged that the respective wires
forming the electrical communication may be coupled together practically as
herein described and set forth.
Thirdly. The employment of a combined commutator and indicator as illustrated
and described under Figs. 2, 3 and 4, for use with the cord or other like mechanical
means for raising the alarm and indicating the vehicle or compartment in which
it has been raised practically as herein described and set forth.
Fourthly. The combined arrangement consisting of disposition of circuits,
internal cord means of communication, commutator, and coupling, as herein de-
scribed and set forth.
1011
1
f Wal
1808