Improvements in and connected with Electrical Signalling for Railways.
Year: 1891

page_text: Date of Application, 17th Mar., 1891
Complete Specification Left, 17th Dec., 1891-Accepted, 5th Mar., 1892
PROVISIONAL SPECIFICATION.
Improvements in and connected with Electrical Signalling for
Railways.
I, GEORGE FREDERICK ATTREE of 8 Hanover Crescent, Brighton, Sussex,
Auctioneer do hereby declare the nature of this invention to be as follows:-
The object of this invention is, firstly, to enable engine drivers to either
electrically or telephonically communicate with the signalman in his box, when a
certain distance is between them, and the signalman to communicate with the
driver; secondly, to enable the signalman to operate a danger signal placed on the
engine; thirdly, to cause the train to advise the signalman of its approach.
According to this invention a secondary battery or other source of electricity is
arranged preferably under the signalman's box, this is in connection with an
uncovered electrical lead or conductor placed between the lines, each lead is
preferred to be laid in duplicate, and is carried into the signalman's box and
connected to a lamp, and to a switch and convertor. The engine is fitted with red
and green lamps or a lamp with movable red and green shades.
The front of the engine is fitted with contact makers, consisting of disc wheels
arranged to bear upon the leads between the lines when the engine meets them,
these contact makers being electrically connected with the lamps or other alarm
apparatus on the engine. The signalman operates the current by the switch or
convertor to show either, the red or green lamp on the engine, and to ring a bell or
blow the whistle when the engine meets the lead, then the signalman is electrically
warned of the same. To prevent bad contact by frost or snow the leads are laid
upon the top of a tubular support through which hot water can be circulated.
Dated March 17th 1891.
FREDERIC PRINCE,
Agent for Applicant.
COMPLETE SPECIFICATION.
Improvements in and connected with Electrical Signalling for
Railways.
I, GEORGE FREDERICK ATTREE of Hanover Crescent, Brighton Sussex,
Auctioneer 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 certain improvements connected with electrical
means for enabling a signalman in his box to communicate a danger or other
signal to the engine driver of an approaching train, and is proposed to be
auxiliary to the existing signals and put into operation by being connected to
the present signal levers in such a manner that the placing of the present
signals at danger or otherwise will give a corresponding signal to the engine
driver on the engine. The other parts of this invention referred to in the
Provisional Specification is not proposed to be proceeded with in this applica-
tion. To enable my invention to be properly understood I will proceed to fully
describe the same with aid of the accompanying drawings.
Figure 1 sectional elevation of permanent way showing part of my invention.
Figure 2 plan of same.
Figure 3 partial sectional view of locomotive and permanent way.
Figure 4 end view of preceding ficara

page_text: Figure 6 cross section on line a, b, Figure 7.
Figure 7 longitudinal elevation of preceding figure.
Figure 8 plan of central part shown in preceding figures at signal box end.
Figure 9 a plan of other end of line beyond signal box where appliance on engine
first makes contact with electrical means of communication.
Figure 10 an enlarged cross section of part shown in Figure 6.
Down the centre of the rails for a certain distance is laid a contact rail A
electrically connected in signal box B. The rail A is supported upon wooden
bearings D resting on support D₁ attached to insulator D' fixed to wooden
frame Dsunk in ground.
Dependent from the engine is an arm C fitted with a shoe E at end to bear
upon the top of rail A to make electrical contact with same. This arm is
pivotted at E to enable it to be lifted off the rail A. when desired by the
screwing down of the rod F which acts upon the top end of C., Arranged
within the cab of the locomotive is one or more glow lamps I which are
electrically connected with the shoe E that they may be lighted by the current
obtained from A when the current is flowing through it by the completion of
the circuit which is done by the signalman putting the signals at danger, the
switch for this purpose being connected to the signal levers in a suitable way
for such purpose; the different arrangements for such purpose will be apparent
to any electrical engineer without further description or illustration.
G represents the wire from signal box to A, and G' the wire from end of rail A
back to signal cabin, to battery; the latter wire is proposed to be carried along
the telegraph poles H.
.
a¹
To ensure that the shoe E shall make good contact with the rail A in
frosty weather this rail is made of the shape clearest shown at Figure 10 being
embedded in a wooden or other suitable support D, within which are one ..or
more metal tubes K, of any suitable shape but preferably round; these tubes
where they bear against each side of the web of rail A are insulated, and it is
proposed that hot water or steam shall be passed through them to give a slight
degree of warmth in the chamber space L inside the wooden lagging D so that
the warmth from the tubes K may be distributed over a larger portion of the
rail A, for which purpose an opening L' is left in the lagging D to enable the
warmth to rise up to the underside of double head of A and so prevent ice
forming on the contact surface. The boiler for supplying the hot water or
steam to the tubes K is proposed to be placed under the signal box at M;
N pipes leading from the boiler to the tubes K. The glow lamps I in cab of
engine have one of their terminals connected to the wire from shoe E and the
other terminal to the metal frame of engine.
The action of this arrangement is as follows on the signalman putting the
signal at danger closes the switch which completes the circuit and lights up a
glow lamp in his cabin by being connected to one of the terminals of his lamp,
the other terminal being connected to earth through engine and rail.
The lighting of his lamp shows the signalman that the contact rail A is in
good electrical condition, and upon the locomotive bringing the shoe E to bear
upon, the top of A, the lamp or lamps I upon the locomotive are at once
lighted, thus giving the required signal to the driver.
It is preferred that the rail A shall be laid in duplicate so that two lamps
on the engine may be lighted, one showing a green light and the other red.
If only one lamp is used it should show a green light, the extinction of the light
being considered as the danger signal. The electric current necessary to work
these signals is best generated at a high potential and a transformer used to
reduce the current to required potential, by this means one source of electricity
would serve the signal cabins over a distance of several miles. To give due
effect to this system the contact rail A should extend from the signal cabin to
such distance beyond the distance signal as the signal is visible. The contact

page_text: rail A has been described and illustrated as being placed between the rails
which is considered the most convenient but it may be located in any other
position if found more suitable.
Having now particularly described and ascertained the nature of the inven
tion and in what manner the same is to be performed, I declare that what I
claim is.
1. In electrical signalling on railways, the combination with a contact arm C
electrically connected with a lamp or other signal on the engine, of a rail A to
convey the current laid in the manner herewith described and illustrated by the
accompanying drawings.
2. In electrical signalling a contact rail A laid so as to be warmed when required
to prevent the formation of ice on top, substantially as hereiubefore described and
illustrated by the accompanying drawings.
3. The combination of parts constructed and operating as hereinbefore described
and illustrated for enabling a signalman to communicate a signal to an approaching
train.
1001
FREDERIC PRINCE,
1, Quality Court, Chancery Lane, London, Agent for Applicant.