Improvements in Actuating Points and Signals on Railways and Mechanism for Effecting same.
Year: 1888

page_text: Date of Application, 22nd June, 1888 -
Complete Specification Left, 23rd Apr., 1889-Accepted, 22nd Aug., 1889
PROVISIONAL SPECIFICATION.
Improvements in Actuating Points and Signals on Railways and
Mechanism for Effecting same.
I, CUTHBERT ELLISON CARR, of Dunston Hill, Whickham, in the County of
Durham, Engineer do hereby declare the nature of this invention to be as follows:-
The objects aimed at in this invention are:-
'
1st. To simplify and secure greater efficiency and quickness in opening and closing
the points or switches on railways and fixing them in their proper position when so
opened or closed.
2nd. To cause the signals, whether interlocked or not with the points, to be
actuated so as to make it impossible they shall fail to work.
3rd. To enable the signalman to effect all the requisite movements of the points,
with their locking wedges, the signals, whether interlocked or not, by moving a single
lever into various positions properly defined upon an index plate..
The existing systems of actuating points and signals on railways all involve a
multiplicity of levers requiring considerable strength, especially in bad weather, on.
the part of the signalman who has besides to move rapidly over a considerable
distance from end to end of the series of levers. Thus in the signal box at a
junction of branches with the main lines and with sidings and crossings a great
number of levers are required to effect all the operations upon the points, locking
bars, wedges, and the interlocked, and other signals, whereas my system would
require only about one fourth of the working parts and one main lever handle
actuating, by a succession of movements by the signalman, the mechanism by
which all the requisite movements are effected.
According to my invention these movements are effected by the motive power of
water or other liquid under pressure or by compressed air but as hydraulic
pressure will generally be most readily available I will describe the mechanism as so
actuated.
There will be in the signal cabin one or more sınall accumulators fitted with a
A number of hydraulic
hand pump or other apparatus for obtaining pressure.
cylinders, corresponding to the requirements of the station as to points and signals
and preferably connected in pairs, so that each pair will act to open and close a
set of points or actuate signals. Each cylinder is preferably furnished with a
valve or cock which in one position admits water from the accumulator to
actuate the piston or ram and in another position will allow the water to escape from
the cylinder. These valves or cocks are all connected by a rod to the signalman's
hand lever which moves in a sector guide through about 90° of a circle and by moving
this lever into a sequence of positions from one extreme to the other, assisted by
supplementary valves or cocks actuated automatically by tappets from the rams or
piston rods of the cylinders, all the requisite operations upon the points and signals
are effected by the hydraulic pressure in the cylinder.
As an illustration I take the case of facing points of a single branch junction on one
line of a double line of railway protected by distant and stopping signals, and with
locking bar and wedges attached to the switch mechanism. To effect the necessary
movements in such a case I propose to use 6 single acting hydraulic cylinders in pairs
which I will call A A¹-B B-C C¹ each fitted with a valve which will admit water
under pressure to the cylinder from the accumulator and will allow the water to escape
from the cylinder to waste tank. The pipes connecting the valve with the accumulator
and with the waste tank in the case of the cylinders which act upon the signals, are
fitted with supplementary valves or cocks which are actuated automatically by tappets
on the piston rods or rams. The valves connected with the cylinders are all actuated

page_text: .
by short arms which are connected by a rod attached to the main lever worked by the
signalman which, when the apparatus is out of action stands in its central position.
The cylinder A lowers the main line distant signal; A' lowers the main line stopping
signal; the cylinders B B¹ move the switches and actuate the locking bar and wedges;
the cylinder C lowers the branch line stopping signal and lowers the branch line
distant signal. The cylinder B is called the main line switch cylinder because it is
from it that the power comes to set the switches, locking bar and wedges for the main
line and B' is called tlie branch line switch cylinder because it sets the switches
locking bar and wedges of the branch line.
We will assume that the switches are set for a train to turn off onto the branch
line and that the branch line signals are lowered. Of course the main line signals
will be in their normal position, that is at danger. With the switches and signals in
these positions the condition of the valves of cylinders will be as follows: The pressure
branch of the valves of cylinders A A¹ actuating the main line signals will be closed
and the corresponding escape branch of the valves will be open. The pressure
branch of the valve of the main line switch cylinder will be closed and the escape
branch of the valve will be open. On the other hand the pressure branch of valve of
the branch line signal cylinder will be open and the escape branch of the valve will
be closed; the pressure branches of the valve of the branch line switch cylinder B¹
will be open and the escape branch of the valve will be closed until the switches are
operated, when the reverse is the case.
Let us now suppose that it is desired to move the switches and signals so as to set
them right for a train passing along the main line. One object of the invention being
speed in working, the apparatus is designed to perform all the necessary motions
when set in movement by one single pull at the main lever. But for the sake of
describing the action of the valves it will be best to state in succession the effect in
proper sequence of each of several parts of the motion communicated to them by the
one pull at the handle.
The 1st part of the motion closes the pressure branch valve and opens the escape
branch of valve of cylinder C₁ thus allowing the branch distant signal to rise to
danger by the action of the balance weight. The second part of the motion closes
the pressure branch and opens the escape branch of the valve of cylinder C thus
allowing the branch stopping signal to rise.
The 3rd part of the motion closes the pressure and opens the escape branch of the
valve of the cylinder B¹ thus removing all pressure from the branch line switch
cylinder but communicating no motion to the switches, wedges or locking bar and the
last part of the backward motion of the piston of cylinder C would close the supple-
mentary cock or valve in the pressure pipe of cylinder C¹.
The handle is now in its central or normal position. All pressure branches of main
valves would be closed and all escape branches of main valves would be open. This
is the position in which the apparatus would usually be except when it had been put
in motion to allow the passage of a train. The 4th part of the motion of the valves
would close the escape branch and open the pressure branch of valve of cylinder B.
This would cause the switches to be moved over into the position suitable for a train
passing along the main line.
This 5th motion of the valves would put pressure on the main line stopping signal
cylinder A and lower the main line stopping signal. But owing to the supplementary
cock or valve on the pressure pipe which is opened automatically by the piston of the
main line switch cylinder B at the very end of its stroke no pressure is exerted on the
signal nor on any of its apparatus until, as will subsequently be shown, the switches
have completed their motion. The last part of the forward motion of the piston of
cylinder B would correspond with the last part of the backward motion of the piston,
of cylinder B¹ and during this the piston of cylinder B¹ would close the supple-
mentary cock or valve in the pressure pipe of cylinder C. The last part of the
motion of the piston of cylinder B would open the supplementary valve or cock in
the pressure pipe of cylinder A' thus allowing the main line stopping signal to be
lowered.

page_text: The last part of the motion of the piston of cylinder A' would in the same way
open the supplementary cock or valve in the pressure pipe of cylinder A and allow
the main line distant signal to be lowered at the right moment.
The 6th and last part of the motion of the valves would open the pressure branch
of valve of cylinder thus causing the main line distant signal to fall and thus the
operation of changing the switches and signals is completed.
It will be seen from the above description and what is to follow that the signalman
can by one pull at the main lever handle almost simultaneously close all the branch
line pressure valves, open all the branch line escape valves, close all the main line
escape valves, and open all the main line pressure valves in such a way as
instantaneusly to set in motion forces which will immediately perform in their proper
sequence the following actions viz.: 1st raise the branch distant signal, 2nd raise
the branch stopping signal, 3rd move the locking bar and withdraw the wedges, 4th
shift the points and replace the locking bar, 5th lower the main line stopping signal
and replace the wedges and finally lower the main line distant signal thus completing
with one action of the signalman what would now require from five to seven motions
and from five to six levers to perform.
But it is not always that it is desired to perform the whole of this series of actions
at once and those of them that it can ever be necessary to perform singly or in any
other combination can be so performed by the proposed appliances just as readily as
by any of the existing systems and generally more readily..
that a
Thus if we suppose the switches and signals set for the branch and suppose
train for the branch comes along. As soon as it has passed the distant signal it will
be necessary to raise it to danger without moving the stopping signal or switches.
This is done by merely moving the handle through a 6th part of its whole travel and
letting it rest there.
When the train has passed the stopping signal it will be necessary to raise it also
and it might not be desirable to shift the switches. This can be effected by simply
moving the handle another 6th part of its total travel. A backward movement of
the lever will put one or both signals down again. A further movement of the
handle through ths of its travel would shift switches without moving any of signals
and a backward motion through the latter ths of the travel of lever would move the
switches back again. When handle is in central position all pressure valves are
closed and all escape valves open.
Having now described the origin of the power and the manner in which it operates
upon the mechanism in the signal cabin I proceed to describe the mechanism by
which the various movements will be generally transmitted to the points or switches,
locking bars and wedges and to the signals, when interlocked, at the various branches,
sidings and crossings connected with a junction.
Signals will generally be worked by wires as in existing systems.
The switches will be generally connected with the mechanism in signal cabin by
rods which on arriving opposite to the switches to be moved will be attached to a
plate working on guides, so as to move parallel to the rails. This sliding plate is
attached by a link to a pivotted arm, at the same point being attached a rod passing
under the rails and attached to the transverse tie bar connecting the switches. The
form of this attachment is such that during the first portion of the motion of the
sliding plate practically no motion is conveyed to the switches the moving of the
switches being effected by the next portion of the movement of the sliding plate and
during the last portion of its movement after one switch is closed against the main
rail the further movement of the sliding plate does not act upon the switches. Thus
the operation of closing or opening the switches is effected smoothly and without jar
or shock. The same functions may be effected by a cam shaped lever operated by a
slot in a sliding plate by means of which differential motion may be communicated
to the switches.
The locking bar is actuated through a suitable link and lever by the same sliding
plate which moves the switches the first motion of the locking bar being given
before the switches begin to move, the middle part of the motion of the sliding bar

page_text: scarcely affecting the locking bar, and the last portion of the motion, after the
switches have come to rest, bringing the locking bar into its open or normal position.
The wedges or point detectors are each attached to a transverse rocking bar
passing under the rails, the wedges being actuated each by its own transverse bar in
such a manner that the wedge next the closed switch is thrust forward and holds it
fast whilst the wedge next the open switch is drawn back. The withdrawal of the
wedges is effected by the first portion of the motion of the locking bar, through
suitable links and levers and they are pushed home by the action of the stopping
signal rod or wire as the signal is lowered but in being raised to danger the signal
mechanism is in no way dependent upon or affected by the wedge mechanism.
An important feature of the insertion of the wedges is that the insertion of one
wedge proves both switches to be in position for the reason that the power to move
the switch is applied in every case to the switch which is to be opened and by it to
the switch which is to be closed by the operation of tie bars so arranged that the
closing switch cannot fully close unless the opening switch is fully open and there-
fore if the wedge next closed switch can be forced home it indicates that both closed
and open switchs are in position.
Although I have described the operating cylinders with their valves and mechanism
as situated in the signal cabin and thence transmitted to the points or switches,
locking bars, wedges and to the signals, I may in some cases place the cylinders and
their mechanism opposite the points to be actuated or at any point between them and
the cabin.
Having fully described the action of my invention as applied to the supposed case
of facing points of a single branch junction on one line of a double of railway
protected by distant and stopping signals it will be readily understood that the
requirements of other cases as to branches, crossings, sidings and signals can be
provided for by modifications of the number and arrangement of the cylinders with
their actuating valves and gear and the mechanism transmitting the power from
the signal cabin to the switches, locking bar signals and wedges.
Dated this 22nd day of June 1888.
**
COMPLETE SPECIFICATION.
Improvements in Actuating Points and Signals on Railways and
Mechanism for Effecting same.
I, CUTHBERT ELLISON CARR, of Dunston Hill, Whickham, in the County of Durham,
Engineer, do hereby declare the nature of said invention and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement :-
The objects aimed at in this invention are :—
"
1st. To simplify and secure greater efficiency and quickness in opening and closing
the points or switches on railways and fixing them in their proper position, when
so opened or closed.
2nd. To cause the signals, whether interlocked or not with the points, to be actuated
so as to make it impossible they shall fail to work.
3rd. To enable the signalman to effect all the requisite movements of the points,
with their locking bars and wedges and the signals, whether interlocked or not, by
moving a single lever into various positions properly defined upon an index plate.
The existing systems of actuating points and signals on railways all involve a
multiplicity of levers requiring considerable strength, especially in bad weather,
on the part of the signalman who has besides to move rapidly over a considerable
distance from end to end of the series of levers. Thus in the signal box at a junction
of branches with the main lines and with sidings and crossings a great number of
levers are required to effect all the operations upon the points, locking bars, wedges,

page_text: and the interlocked, and other signals, whereas my system would require only about
one fourth of the working parts and one main lever handle, actuating one pair of
switches with their locking bar, wedges and signals by a succession of movements
by the signalman of the mechanism, by which all the requisite movements are
effected.
According to my invention these movements are effected by the motive power of
water or other liquid under pressure, or by compressed air, but as hydraulic pressure
will generally be most readily available I will describe the mechanism as
actuated.
SO
There will generally be in the signal cabin one or more small accumulators, fitted
with a hand pump, or other apparatus for obtaining pressure. Although in some
cases there may be sufficient natural pressure of gravitation or the pressure of the
atmosphere may be made available against a vacuum. A number of hydraulic
cylinders, corresponding to the requirements of the station as to points and signals,
and preferably connected in pairs so that each pair will act to open and close a set of
points or actuate signals will be arranged in a convenient position. Each cylinder
will be preferably furnished with a valve or cock which in one position admits water
or fluid under pressure to actuate the piston or ram and in another position will allow
the water or other fluid to escape from the cylinder. These valves or cocks will be all
connected by a rod to the signalmans hand lever, which moves in a sector guide
through about 90° of a circle, and by moving this lever into a sequence of positions,
from one extreme to the other, assisted by supplementary valves or cocks actuated
automatically by tappets from the rams or piston rods of the cylinders, all
the requisite operations upon the points and signals are effected by the hydraulic
pressure in the cylinder.
I now proceed to describe my invention in a detailed manner and to illustrate by
the accompanying drawings the manner in which it may be carried into practical
application, to one pair of facing points or "switches" of a branch junction on a
double line of railway protected by distant and stopping siguals and with locking bar
and wedges I wish it however to be understood that the hydraulic cylinders and their
operating mechanism, also the mechanism by which the power is transmitted to the
switches and to the signals, and the mechanism by which the switches locking bar and
wedges are operated may each be modified in arrangement and details of
construction without departing from the principle of my invention and still securing
the objects aimed at.
On the accompanying 3 sheets of drawings:
Sheet 1. shews a general arrangement of the hydraulic cylinders and their
mechanism in the signalmans cabin Fig. 1. being a side elevation Fig. 2 an end
elevation and Fig. 3 a plan.
Sheet 2 shews to an enlarged scale the hydraulic cylinders and their connections
required to work one pair of switches between a main line and a branch, or siding,
with 2 distant and 2 stopping signals connected with each, Fig. 4 being a side elevation,
in section and Fig. 5 an end elevation.
Sheets 3 and 34 shew different arrangements of the mechanism at the switches
which I propose to use in connection with the other portion of my invention but both
of which are capable of being used in connection with other means of actuating
switches. On sheet 3 Fig. 6 is a side elevation and Fig. 7 a plan of the mechanism
necessary for one pair of switches and on sheet 3^ Figs. 8. 9 and 10 shew the mechanism
in plan in 3 positions of an alternative arrangement.
Sheet 4, shews an outline diagram of the method I propose to adopt for working
the switches, with their safety locking bars and wedges, and the signals connected
with them, when the hydraulic cylinders are situated at the switches, or near to them,
by means of mechanism operated from lever handles in the signal cabin, which in
certain cases will be desirable.
The same letters refer to corresponding or analogous parts on all the figures on
sheets 1, 2 and 3 where such parts occur.
On sheet 1 Figs. 1. 2 and 3 shew the cylinders, which are horizontal, arranged in

page_text: 4
groups of 5 each disposed vertically and standing upon the floor of the signal cabin,
each group operating one pair of switches by the handles marked 1, 2, 3 & 4, with
their locking bars and wedges, and a distant and stopping signal for the main line
and the branch respectively and on sheet 2 Figs. 4 and 5 shew details (Fig. being
in section) to an enlarged scale, of the hydraulic cylinders with their valves and
connections. Referring to both these sheets A is the cylinder which actuates the
main line distant signal and A¹ the cylinder which actuates the main line stopping
signal, is the cylinder which actuates the branch stopping signal and C₁ that
which actuates the branch distant signal. All these cylinders are single acting the
wires or cords to the signals forming loops round the sheaves on the outer ends of the
rams so that they have twice the travel of the rains.
The cylinder which operates the switches and their safety mechanism marked B B²,
is shewn double acting as giving greater facility for working the valves than with
separate single acting cylinders.
The signalman's hand lever standing in its central position in sector as shewn on
Fig. 1. all the signals are at danger closing both the main line and the branch, all the
valves being closed against pressure and open to escape.
When the hand lever is in the extreme position to the right marked 1, Fig. 1,
sheet 1. the switches are set for the main line, the stopping and distant signals of which
are lowered whilst the stopping and distant signals of the branch are at danger. If
it is now desired to change the switches and set them for the branch, the hand lever
is moved toward the left hand. The 1st part of the motion by the downward move-
ment of the slotted bar E acting through the inner slot closes the valve of cylinder A
to the pressure and opens it to the escape thus allowing the main line distant signal to
rise to danger.
The 2nd part of the motion into the position marked 2 Fig. 1, sheet 1 closes the
valve of cylinder A to pressure and opens it to the escape thus allowing the main line
stopping signal to rise to danger.
The 3rd part of the motion into the position marked 3 Fig. 1, sheet 1 by the
operation of the outer slot in the bar E closes the valve on outer end of the switch
cylinder B B at B to pressure and opens it to the escape thus removing all pressure
from the main line switch but communicating no motion to the switches wedges or
locking bar.
In the meantime the last part of the backward motion of the ram of
cylinder A¹ has closed the supplementary cock or valve marked S VA Figs. 4 & 5
sheet 2 in the pressure pipe of cylinder A by means of the rod & acting in the spindle S
of the cock.
The 4th part of the motion into the position marked 4 Fig. 1, sheet closes the
escape valve of the switch cylinder B B' from the outer end at B¹ and opens it to
admit pressure to that end moving the switches by the intervention of the lever F
and rods G into position for a train passing along the branch the last part of the
motion of the piston of the switch cylinder having already by the slotted rod r
actuated by the bell crank be and rod r from the lever F automatically opened the
supplementary cock marked S V° on the pressure pipe of the cylinder C working the
branch stopping signal, all the intermediate actions of raising the locking or safety
bar withdrawing and replacing the wedges having been performed in their proper
sequence by the mechanism at the switches.
The 5th part of the motion into the position marked 5 Fig. 1 sheet 1 opens the
valve of cylinder C to pressure and closes the escape and the ram, moving
outward, pulls down the branch stopping signal, opening at the same time the
supplementary cock or valve marked S Ve in the pressure pipe of cylinder C¹ actuated
by the rod to a lever on spindle s of the cock. The last part of the motion into the
position marked 6 Fig. 1 sheet 1 opens the valve of cylinder C¹ to pressure and closes
the escape and the ram, moving outward, pulls down the branch distant signal.
It is to be noted that the signal cylinder C cannot operate to lower the branch
stopping signal until the switches are fully moved and set, owing to the supplementary
pressure valve being only then opened and in the same way the signal cylinder C¹
cannot lower the branch distant signal until the lowering of the stopping signal by

page_text: cylinder Chas opened the supplementary valve of C. The branch line is now open
and the main line closed with the signals at danger the valves of the signal cylinders A
and A¹ being closed to pressure but open to escape.
Let us now suppose that it is desired to move the switches and signals so as to set
them right for a train passing along the main line. One object of the invention
being speed in working, the apparatus is designed to perform all the necessary
motions when set in movement by one single pull at the main lever. But for the
sake of describing the action of the valves it will be best to state in succession the
effect in proper sequence of each of several parts of the motion communicated to
them by the one pull at the handle.
The 1st part of the motion from its extreme position on the left hand toward the
position marked 5 Fig. 1 sheet 1 closes the valve of cylinder C¹ to pressure and opens
it to escape thus allowing the branch distant signal to rise to danger by the action
of the balance weight. The 2nd part of the motion into the position marked 5 Fig. 1
sheet 1 closes the valve of cylinder C to pressure and opens it to escape thus allowing
the branch stopping signal to rise. The 3rd part of the motion into the position
marked 4 Fig. 1 sheet 1 closes the pressure and opens the escape branch of the valve
of the switch cylinder B, B₁ at the outer end B₁ thus removing all pressure from
the branch line switch cylinder but communicating no motion to the switches, wedges
or locking bar and the last part of the backward motion of the ram of cylinder C
would close the supplementary cock or valve in the pressure pipe of cylinder C.
The 4th motion into the position marked 3 Fig. 1 sheet 1 of the hand lever moves
the valve of the switch cylinder so as to admit pressure to the front end of the
cylinder at B¹ thus causing the piston to travel back and to set the switches for a
train passing along the main line. The 5th motion of the hand lever into the position
marked 2 Fig. 1 sheet 1 would put pressure on the main line stopping signal
cylinder A and lower the main line stopping signal. But owing to the supplementary
cock or valve S VAI in the pressure pipe which is opened automatically by the piston
of the main line switch cylinder B, B₁ at the very end of its stroke by the slotted
rod sr actuated through the bell crank be by the lever F no pressure is exerted on
the signal nor on any of its apparatus until, as will subsequently be shewn, the
switches have completed their motion. The last part of the forward motion of the
piston of the switch cylinder B, B' would correspond with the last part of the backward
motion of the piston of that cylinder and during this the piston of the switch
cylinder B B would close the supplementary cock or valve in the pressure pipe of
cylinder C. The last part of the motion of the piston of cylinder B B₁ would open
the supplementary valve or cock S VAI on the pressure pipe of cylinder A¹ by the
rod to a lever on the spindles of the cock thus allowing the main line stopping
signal to be lowered when the handle reaches the position marked 2 Fig. 1
sheet 1.
The last part of the motion of the piston of cylinder A¹ would in the same way
open the supplementary cock or valve in the pressure pipe of cylinder A by the
action of the lever E and allow the main line distant signal to be lowered when the
handle reaches the position marked 1 Fig. 1 sheet 1.
The 6th and last part of the motion of the handle into the position marked 1, Fig. 1
sheet 1 would open the pressure branch of cylinder A thus causing the main line
distant signal to fall and thus the operation of changing the switches and signals is
completed.
It will be seen from the above description and what is to follow that the signalman
can by one pull at the main lever handle almost simultaneously close all the branch
line pressure valves, open all the branch line escape valves, close all the main line
escape valves, and open all the main line pressure valves in such a way as instantaneously
to set in motion forces which will immediately perform in their proper sequence the
following actions riz.: 1st raise the branch distant signal, 2nd raise the branch
stopping signal, 3rd move the locking bar and withdraw the wedges, 4th shift the
points and replace the locking bar, and wedges, 5th lower the main line stopping
signal and finally lower the main line distant signal thus completing with one action

page_text: of the signalman what would now require several motions and several levers to
perform. But it is not always that it is desired to perform the whole of this series
of actions at once and those of them that it can ever be necessary to perform singly
or in any other combination can be so performed by the proposed appliances just as
readily as by any of the existing systems, and generally more readily.
Thus if we suppose the switches and signals set for the branch and suppose that a
train for the branch comes along. As soon as it has passed the distant signal it will be
necessary to raise it to danger without moving the stopping signal or switches. This
is done by merely moving the handle through a th part of its whole travel and letting
it rest there.
When the train has passed the stopping signal it will be necessary to raise it also
and it might not be desirable to shift the switches. This can be effected by simply
A backward movement of the
moving the handle another th part of its total travel.
lever will put one or both signals down again. A further movement of the handle
through th of its travel would shift the switches without moving any of the signals
and a backward motion through the latter th of the travel of lever would move the
switches back again. When the handle is in central position all pressure valves are
closed and all escape valves open.
Having now described the mechanism by which the power of the water or fluid
under pressure from the accumulator is caused to operate in the switch and signal
cylinders I proceed to describe the mechanism by which the various movements may
be transmitted to the switches with their locking bar and wedges and to the signals
when interlocked.
In Fig. 1 (sheet 1) the movements of the piston of the switch cylinder are com-
municated through the lever F to the switch rods G which pass along the line in the
ordinary manner to the switches to which they are connected by suitable mechanism.
But with iny system I propose in some cases to use water or other fluid (as a substitute
for the switch rods) conveyed in pipes between the signal cabin and the switches and
this alternative method is shown on Fig. 4 (sheet 2) and on Fig. 7 (sheet 3). It
consists of a cylinder D, D¹, without valves, the packed plunger of which is connected
with the piston rod of the switch cylinder B, B. From the opposite ends of this
cylinder, pipes F. P convey columns of fluid, answering to rigid rods, to a double
acting cylinder G G', without valves, (see sheet 3 Fig. 7) placed at the switches and
connected to their operating mechanisın.
Referring now to sheet 3 of the drawings Figs. 6 and 7, a bell crank H shewn only
on Fig. 7 is so arranged that one of its arms is connected with the switch rods from
signal cabin or with the piston rod of the cylinder G, G¹ just referred to the other
arm being attached by the rod J to the sliding bar K working in guides L L.
Provision is made in the cylinder G G¹ for arresting the flow of the water as the
piston arrives nearly at the end of its stroke so that the switches come to rest without
shock and a similar provision will be made in the case of the switches worked by rods
previously described. From this sliding bar K are derived all the movements required
to raise the safety locking bar M withdraw the wedges 0, 0¹ from the switches move
the switches N, N₁ replace the wedges and lower the locking bar in the following
sequence viz. :—
The first movement of the sliding bar K by the bell crank Q and connections to
weigh bar P raises the locking bar M, so that the switches cannot be moved if a
train is standing upon or passing over the line, the same action, by means of the
weigh bar R across the line worked by the rocking bar arms, withdrawing the
wedge O of closed switch, the wedge Of of open switch having now scarcely any
motion. The further movement of the sliding bar K causes the arm S which has
its fulcrum on a fixed pin T, on which it slides by the slot U, to move upon its
fulcrum until the stud V, fixed in it, enters the slot V1 in the switch bar W and the
stud, travelling in the slot with the continued travel of the sliding plate, commences
to open the closed switch and to close the open switch with a very slow movement
which is greatly increased as the switches come over by the stud operating in the
slot V¹ so as to give a more rapid movement until it reaches a position in its travel

page_text: when very little motion is given to the switch bar W when the switches are brought
slowly to rest in their changed positions. The object of the two horns on the switch
bar is to ensure the switches remaining in their changed positions just previous to
the insertion of the wedges, the end of the arm S, in contact with the horn preventing
any backward movement.
As will be seen by Fig. 6 (sheet 3) the wedges O, O' are so connected with the
raising or lowering of the locking bar M, that as the locking bar begins to rise it
withdraws the wedge O from the closed switch but scarcely moves the wedge O' of
the open switch and as it falls it forces home the wedge of the newly closed switch.
I have not shewn any connection between the signals and the wedges as I consider
every condition of safety is secured by my system without such connection.
An important feature of the insertion of the wedges is that the insertion of one
wedge may be made to prove both switches to be in position for the reason that the
power to move the switch may be applied to the switch which is to be opened and by
it to the switch which is to be closed by the operation of tie bars so arranged that
the closing switch cannot fully close unless the opening switch is fully open and
therefore if the wedge next closed switch can be forced home it indicates that both
closed and open switches are in position.
In my Provisional Specification I described, as well as that which 1 have just
described and illustrated, an arrangement of mechanism for actuating the switches
and which is very suitable for simple switches without locking bar or wedges
is shewn on sheet 34 on which Figs. 8. 9 and 10 shew the mechanism in
three positions. Fig. 8 shews one switch closed the other full open Fig: 9 the
two switches having moved half over and Fig. 10 having come fully over
and changed from one line to the other. The bar K sliding in guides L L. The
switch rod G takes hold of a lever H, having its fixed fulcrum at F, the slotted end
of which works on a stud in the bar K from which a bridle link M connects the
lever H with the end of an arm N working on a fixed fulcrum at O and to this arm
is connected the switch bar P which takes hold of the transverse tie bar T between
the two switches. It will be seen that the arm H in the position shewn on Fig 8,
moving in the direction of the arrow, gives a very slow and gradual movement to the
arm N and the switches are set in motion very slowly and as they approach the
position shewn on Fig. 9 they move much more rapidly until they are coming into
the position shewn on Fig. 10 when they come to rest very slowly.
Although I have described the operating cylinders with their valves and mechanism
as situated in the signal cabin and the power thence transmitted to the points or
switches, locking bars wedges and to the signals, I may in some cases as at large and
complicated junctions place the cylinders and their mechanism opposite the points
and signals to be actuated or at any point between them and the cabin.
I will now describe a case in which the cylinders are so placed, with reference to
sheet 4 of the accompanying drawings. The letters of reference on this sheet are
independent of those on sheets 1. 2. and 3.
For illustration I take the case of a branch junction with the main line, the signal
cabin A being situated at a considerable distance from the switches, and another
branch or a siding, may be supposed to be worked at a distance from the signal cabin
in the other direction. Thus there will be in the signal cabin 4 handles, viz.:
2, actuating the switches of the junction with the up and down lines respectively and
the distant and stopping signals, controlling the main line and the branches, shewn
on the drawing, 2, actuating the switches of the junction or siding, in the opposite
direction from the signal cabin, (not shewn on the drawing) with their distant and
stopping signals, controlling the main line and the branches.
From the signal cabin A, in which the accumulator is placed, a pressure pipe B
(indicated by a thick line) and an escape pipe C (indicated by a thin line are laid
in each direction, along the side of the main line, to any required distance, and
from these two main pipes, branch pipes, forming loops, are taken off at the points
required to lead to and from the cylinders, by which the switches are moved and
B

page_text: the signals lowered. The pressure pipe of each loop is indicated by a thick line
and the escape pipe by a thin line.
The switch cylinders D and D¹ are each double acting and are attached to the
switches direct or by any convenient connection, D actuating the switches of the
down line and its branch and D₁ those of the up line and its branch. From each
end of each of these cylinders a pipe, which is alternately pressure and escape leads
to the loops F F¹ and G, G₁ the legs of which join the main pressure and escape
pipes. Taking the cylinder D, for example, actuating the switches of the down line
junction. In each leg of the loop F and F¹ is a pressure and escape cock or valve
indicated by the letters P, P¹ and E, E¹. P being opened and P¹ closed, by the rod
from the signal cabin, admits pressure to one end of the cylinder, the fluid already in
the cylinder escaping through the cock or valve E¹ opened by the valve rod which has
simultaneously closed E and thus the switches with the locking or safety bar and
wedges are changed.
The signal cylinders, all single acting, are as follows viz.:
Up-line main distant and branch distant signals lowered by the cylinders H
and H¹.
Up line main stopping and branch stopping signals lowered by the cylinders J
and: J¹.
Down line main distant signal lowered by the cylinder K.
Down line branch distant signal lowered by the cylinder L.
Down line main stopping and branch stopping signals lowered by the cylinders M.
and M¹.
The two dotted lines marked VR and VRD indicate respectively the slotted rods,
answering to the slotted rod E of sheets 1 and 2, by which the cocks or valves in the
loop pipes of the switches and signals cylinders are opened or closed from the
handles in the signal cabin, VR working those connected with the up line branch
switches and signals and V RD those connected with the down line branch and
signals. The slotted rods VR and V RD may be only at the points where the cocks
or valves occur and connected over the intervening distances by wires or cords so
arranged as to act in tension in both directions and provided with means of adjust-
ment. The position of the signals shewn indicate that the switches are set for the
main up line and for the branch onto the main down line. In this arrangement
the supplementary valves on the pressure pipes of the signal cylinders will be
actuated by mechanism connected with the piston rods of the switch cylinders.
The sequence of consecutive movements of the hand lever by the signalman are
precisely similar to those already described, where the cylinders were in the cabin,
and all the operations upon the switches and signals take place in the same order.
Although I have not referred to cases in which extra signals to be operated—such
as. an intermediate signal, upon a curve a starting signal or a "recall" signal to
warn the driver, after having started that he is to stop and return, these cases can
be provided for under my invention by very simple adaptations of the mechanism.
in connection with additional cylinders in the signal cabin or at the signals.
In some cases, especially in winter, the water may be mixed with some substance
which will prevent it freezing or instead of water some other fluid such as paraffin
or other oil, which will not freeze at low temperatures, may be used as the fluid is.
used over and over without any sensible waste. As however the pipes will be laid
below the surface as well as the cylinders in the arrangement, shewn on sheet 4, and
as in the other arrangement the cylinders are in the cabin I do not apprehend any
trouble from frost.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
:-
First. Actuating the switches and signals on railways by fluid, air or gas under
direct. pressure, or the pressure of the atmosphere acting against a vacuum, admitted

page_text: to and released from cylinders, fitted with pistons or rams, by cocks or valves,
operated by mechanism connected with the signalman's hand lever in such a manner
that a succession of movements of the hand lever from one extremity of its travel to
the other extremity will cause the pistons or rams by suitable connections to the
switches and signals to perform the following operations, on one pair of switches with
their protecting signals, in their proper sequence viz.: 1st release a distant signal
2nd release a stopping signal allowing them both to rise to danger; 3rd remove all
pressure from the switches as then set; 4th raise the locking or safety bar and with-
draw the wedges, move the switches over, lower the locking or safety bar and replace
the wedges; 5th lower a stopping signal 6th lower a distant signal and, by backward
movements of the hand lever from certain positions, allow a signal, previously
lowered, to rise to danger when necessary and again lower it without interference
with the other signals or with the switches and to perform all other operations
required in connection with starting, recall or intermediate signals.
Second. In apparatus for actuating the switches and signals on railways by fluid or
gas under direct pressure, or the pressure of the atmosphere acting against a vacuum,
operating as above described, the application of supplementary cocks or valves opened
or closed automatically in such a manner as to prevent a signal being lowered until
the switches have moved completely over and are wedged in position, substantially as
described and illustrated.
Third. For the purpose of actuating the switches and signals on railways by water
or other fluid under pressure in the sequence described in claim 1, the apparatus con-
sisting, for each pair of switches and their signals, of one double acting cylinder for
moving the switches, fitted with a piston and valves; and four single acting cylinders
for the signals, fitted with rams and pullies for the cords or wires which lower the
signals; a signalmans hand lever working in a sector, with index plate attached; a
valve rod or rods, operated by the hand lever, so slotted as to open or close the
valves of the switch and signal cylinders at the proper times; supplementary valves
on the signal cylinders operated by a slotted rod, through connections to the piston
rod of the switch cylinder, and by connections to the adjoining signal cylinder, so as
to control automatically the lowering of the signals, and levers with rods and con-
nections to the switches, or the alternative connection in which a cylinder in the
signal cabin is caused, through pressure conveyed in pipes to and from the switches,
to move a piston in a cylinder at the switches in either direction, and so, by con-
nections from the piston rod to the switch rod, to actuate the switches, with their
locking or safety bar and wedges the whole constructed and operating substantially as
described and illustrated by the drawings hereunto annexed.
Fourth. For the purpose of actuating the switches and signals on railways, by
water or other fluid, under pressure, the application of cylinders, placed near the
switches and signals, connected by loop pipes fitted with cocks or valves in communi-
cation with main pressure and escape pipes, laid along the side of railway; the cocks or
valves in said loops being operated by slotted rods worked by hand levers in the signal
cabin and supplementary valves or cocks in the pressure pipes of the signal cylinders
operated automatically by the action of the switch cylinders, so as to actuate the
switches and signals substantially as described and in part shewn.
Fifth. For the purpose of actuating the switches on railways, with or without
locking bars and wedges, by hydraulic or other pressure, or by ordinary manual
power, from the signal cabin the mechanism, consisting of the various parts com-
bined, constructed and operating substantially as described and shewn on sheet 3
and in the alternative form on sheet 3ª.
T. J. DANSON, F.I.P.A.,
2, St. Nicholas' Buildings, Newcastle upon Tyne, Agent for Applicant.