Improvements in Controlling and Working Railway Signals and Points.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Controlling and Working Railway Signals and
Points.
I, ILLIUS AUGUSTUS TIMMIS, of 2, Great George Street, Westminster, S.W., Civil
Engineer, do hereby declare the nature of this invention to be as follows:-
The objects of my invention are to increase the safety of electrically worked
signals, ground discs, & points used in railway traffic.
With these objects in mind I refer to my Patent No. 5718/83 which has for
its main object the reducing of the main or lowering current, in operating signals
and ground discs, to a reduced or holding current, automatically.
Also I refer to my Patent 21496/93 which describes the working of points and
signals electrically and also I refer to my Patent 7827/91 which describes the work-
ing of signals electrically and automatically.
When I use the word magnet I mean an electro magnet. When I use the word
lever I mean a lever or switch or an equivalent. And a circuit means an electric
circuit.
By this invention I introduce a track circuit as hereinafter described, and certain
improved details in the operation of points locking bolts and locking bars.
to the holding current in several
I may arrange the alteration of the "lowering
ways. But I use a track circuit for both safety and economy and I annex several
drawings to illustrate my invention more clearly.
Fig. 1 is a diagram of the working of a signal. S is the signal arm, M the signal
maguet, C the main battery circuit, B the battery, and L the lever, which are all
used to operate the signal arm.
C¹ is the auxiliary or local track circuit, part of which consists of the track rails
In this circuit is the small battery b. Sup-
in the insulated part or block K, K¹.
pose no train or vehicle is in the block K, K1, the magnet m is energised and the
pivoted lever (which in its normal position is kept away from m by a spring or
By this means the con-
by gravity) forms an armature for and is attracted to m.
tacts are closed and thus the circuit C is completed. If then the signalman pulls
over the signal lever L, he closes the contacts t¹ and the lever is held over by the
magnet M which is in the circuit C, and at the same time the magnet M lowers the
signal S from "danger" to "line clear." This is effected and the lowering current
is reduced to a holding current as described in my Patents mentioned above.
In my Patent 5718/83 1 especially show in the sheet of drawings a means of reduc-
ing the main signal lowering current to a smaller holding current by using a lamp
or resistance wire in the signal cabin and in page 5 of the Blue Book this is de-
scribed at some length. I prefer where possible to do this. In automatic signalling
there are no signal cabins and I prefer to effect this as on the Liverpool Overhead
Railway on the signal post. And I have fitted the same arrangement in non-
automatic signalling. I prefer in working points as well as signals to fit all the
switches and electric contacts, where it is practicable, in the signal cabin.
If now a train or a vehicle comes on the track block K, K' the battery b is short

page_text: circuited, the magnet m ceases to be energised and the contacts t are broken and
so is the circuit Č. Then the signal goes automatically to "danger" and the signal
lever L goes back to its normal position. Where possible I prefer to use mercury
contacts. The repeater circuit is not shown, as it is well understood, and not
necessary.
.
Instead of the track circuit battery being used to operate lever l, m may be
used to switch in a third circuit to operate l.
Fig. 2 shows another variation of Fig. 1 but with a difference.
M is the signal magnet and C is the main lowering circuit coming from the
battery and the signal cabin lever. C¹ shows part of the track circuit (see Fig. 1).
But in this latter circuit there are two magnets m and m¹. The working is as
follows: Track empty and C¹ circuit closed m and m² are energised. Lever l' is
attracted to m¹ and contacts t are made but the weighted lever cannot fall
against m as the nose of lever is against rod r, which is against wheel w so
contacts t² are closed. Suppose signalman pulls over his lever and closes his
contacts completing circuit C magnets M and M1 are energised and, as in Fig. 1,
signal is lowered. But the rod is raised by M and the nose of engages below r
and is now held by m, but as falls to m it breaks circuits Cat contacts t².
The signal arm is however held at line clear by land m as already explained.
The signalman knows by his lever falling back that the main circuit is broken and
by his repeater that the signal is held at line clear by the track or other auxiliary
circuit.
If any vehicle comes on to the track circuit rails the small battery is short circuited
and the magnets m and m³ cease to be energised and the signal arm goes to
'Danger." This arrangement does not allow the signalman to control the signal
after it is lowered and therefore is not to be recommended except for automatic
signalling.
Fig. 3 is another variation with two special objects. First to utilize the track
circuit (or of course in this and other cases a third circuit may be switched in by
the track circuit) to hold the signal to line clear. Secondly to give the signalman
control over his signal at all times.
Suppose the track block partly shown (see Fig. 1) to be clear and circuit C¹
complete, magnet m is energised and lever is drawn to it, as shown in Figs. 3
& 4, and the contacts t are closed. It will be noticed also that the contacts (2 at
the top of magnet M are closed and the signal lever L is pulled over and
contacts are closed the circuit C is complete. Magnet M is energised from
battery B and M' is energised from battery (not shewn) in the circuit C¹.
the signal to line clear while M¹ holds the lever over.
M lowers
In every case where the signalman has control over his signals a special switch
may be fitted so that he may break the signal to holding circuit and put it to
danger and his lever to its back position.
But
Fig. 4 shows the position of rod r and swivel joint r¹ after signal is sent to line
clear both and being supported by projection on which is held by m.
as the armature A of magnet M (see Fig. 3) is raised when the signal is sent to
line clear the contacts are broken and C is broken. Thus the signal is held at
line clear by the track circuit current through m. But when a vehicle comes on
the track the circuit C¹ battery is short circuited and m is no longer energised
and the armature A, rods and ¹, and the counter weights press down on the
projection on and force it away as in Fig. 5. In the previous and other figs.
no repeater circuit is shown as electric repeaters are so well known. The track
circuit K, K¹ may be extended to any length that may be desired and it is very
advisable where possible that a track circuit for the Home signal should be
fitted so that it is impossible to lower the Home signal while any vehicle is on
the track between the "home" and the "starter" and "advance starter" or on
the cross over or siding roads that feed the track between these signals.
So far the description of my invention has dealt mainly with the signals worked
from the signal cabin. But in my Patent 7827/91 I describe the working of signals

page_text: In Fig. 6 though a signal must always be at danger in rear of a train and
though no vehicle can be in the rear block when the signal controlling that
block is lowered, still it may be possible for a train to be kept in a block with a
signal at danger behind it and another train, after the signals are lowered, to
draw up to the signal at danger and close to the standing train just in front
of it.
To obviate this, a track circuit as shown in Fig. 6 may be continued from the
beginning of its block to a main circuit "maker" box, which closes the main
circuit.
Fig. 7 describes another method by which there is always one or more blocks
clear in rear of a train as well as a signal at danger. The track between the
two starters say S¹ and S² is divided say into 3 sections or blocks, 1, 2, & 3.
No. 4 is the beginning of the next three sections.
a', a², a³, a, a³, are the respective track section magnets controlling contacts C',
C2, C3, C4, C and operated by circuits 1, 2, 3, 4, 5, from batteries 61, 62, 63, 64, 65.
C¹ and C control 2 circuits each, as shown by the double contacts at C and C+.
Suppose the line is clear and S¹ lowered. A train leaves A and as it enters
section 1 it puts S1 to danger as described in Fig. 6 &c., it closes contacts in w¹
but M¹ is broken by a¹ in contacts C¹. When the train leaves section 1 and gets
into 2, a¹ is again energised and M¹ is completed in C¹ and w¹ and signal or signals
in rear of A are lowered.
Circuit M² remains broken by C². Also by C³ when the train enters
section 3.
The operation is repeated when the train enters section 4. On entering
section 5, S' and H' are lowered through S2 at danger by battery B2 and magnets
in boxes m¹ and m². It is thus clear that if 1, 2, 3, or 4 are occupied S' cannot
be lowered and if 3 or 4 are occupied H¹ cannot be lowered. This arrangement
can be modified. The lowering and holding arrangement have been described.
The main negative in Fig. 7 is indicated by
and arrows.
In wishing to use a track circuit it happens sometimes that the rails are used,
as in the Liverpool Overhead Railway, to convey another current of electricity and
in this case, or if otherwise convenient, I arrange my track as follows. I fix two
small conductors in any convenient position, say two bars of iron or other metal,
directly overhead, so that I can bridge them across by a trolley pressing upwards
or downwards, or sideways. The two bars are in track lengths and the track
circuits are worked exactly as described herein before.
Referring to my Patent 21496/93 I find that it is better to work points as
follows:
If no locking bars are used (see Fig. 1 filed with this Specification). When
the point lever L is actuated it closes a circuit marked a by means of contacts b, b,
to a magnet M which pulls out the locking bolt B. This operation closes a
circuit marked c by means of contacts marked de to another magnet M' which
operates the points. As they complete their travel circuits a is broken by
contacts and g and the bolt B is shot in by means of a spring S, or weight or
both. The bolt being shot in breaks the main point magnet circuit c and closes
the repeater circuit by contact l. The position of the points determines which
point magnet (there is one for operating in each direction, that is magnet M¹ pulls
the points over from the branch line and magnet M² by similar contacts m and n,
o and p, and circuits q and 8, from the main line or straight) shall be operated, and
also controls the signal circuit or circuits, by means of contacts h and i, and j and k
and which are also the repeater contacts. Thus the points must be home and
locked before the repeater can work and also before the controlling signal or
signals can be operated.
If locking bars are used (see Fig. 2 filed with this Specification). The same
description as for Fig. 1 will hold except in so far as the locking bar A is concerned.
The magnet M working the bolt B is not attached direct to B but through a system
of levers and the bar A; on the current passing through magnet M it operates

page_text: "
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so that it is impossible to lower the home signal while any vehicle is on the track
between the " home" and the starter and "advance starter or on the cross
over or siding roads that feed the track between these signals.
So far the description of my invention has dealt mainly with the signals worked
from the signal cabin. But in my Patent 7827/91 I describe the working of
signals electrically and automatically. The Liverpool Overhead Railway signals
are worked by my system and there are many parts of main line railways and many
small railways where the signals could be so worked efficiently and economically
I find that the use of a track circuit as explained above is of great value (in
combination with electro magnets to operate signals and discs) to put signals
And in addition [
to danger by a passing train or vehicle as explained above.
find it advantageous to employ a track circuit to enable a passing train or vehicle to
lower, automatically, the signal or signals in the rear block.
Fig. 6 explains one arrangement for using a track circuit with automatic
signalling, i.e. the signals are put to danger and also lowered to line clear and beld
at line clear by automatically worked electric circuits. The operations being
effected by the trains. If points are worked, they cannot be operated or even
unlocked till all the signals controlling them are put to danger and no signals ..an
be lowered to line clear till the points they control are right and locked. li a
track circuit is not used to put signals to danger or control the putting them to
danger and also to control the lowering of signals in the rear, it is necessary to
use treadles or other mechanical contrivances, with or without the aid of electric
relays, and in this case the last vehicle of a train may be the only one used to
operate the treadle brush or other gearing which is used to close the main lowering
circuit as explained in my Patent 7827/91.
But when the track circuit is used the first or other vehicle is used to do the
work, which closes the main lowering circuit as follows. The first vehicle short
circuits the track battery in the section it enters. And by consequence the track
magnet ceases to be energised. The signal goes to danger. The lowering circait
goes from the main battery through contacts closed by the arm at danger. This
circuit is also closed by contacts. These are broken when the track magnet is
The one
de-energised by the short circuiting of the track battery.
Referring to Fig. 6. A, B, C, are stations. S¹ and S² are starting signals,
and Hand H² are home signals (distant signals are not shown). X, Y, Z, are the
track circuit blocks between S¹ and H2 and their batteries are 61, 62, 63.
main lowering circuit shown is M and its battery B¹. On the signal post
shown boxes m¹, m², m³ which in each case contains the lowering magnets and whe
bearing for switching in the holding current as explained herein before. On tre
arms of S1 and S2 are shown switches w¹ and w². The main circuit M from battery B¹
is closed in contacts w² on S².
Suppose a train to be at station B and S is lowered, the circuit M. is then broken
by switch w² the train leaves block Y and enters block Z. Battery 63 is thus short
circuited and the track circuit magnet in box m³ ceases to be energised and S2 ges
to danger the switch w² completes the main lowering circuit M which goes back to
the lowering magnets in the boxes m¹ and m² on the signal posts S' and H₁ and
(when the train is clear of the block Y and if there are no vehicles in the blocks X
and Y) operates the magnets and puts both signals to line clear. The train
has however the signal S2 at danger behind it. If however there is a vehicle
left behind in X, SI cannot be lowered, or if in Y neither S' or H¹ can
lowered because the track magnets in the boxes m¹ and m² cease to be energised
and thus the circuit M is still incomplete. This arrangement is capable of being
varied in several ways to suit any number of signals.
be
If
It is possible to use a track circuit which only goes through one rail, thus, one
pole of the track battery is well earthed and the other rails are also well earthed
and the lead which leaves the box on the signal post is also well earthed.
then a vehicle enters the block the track battery is short circuited through the
other rail by means of the wheels and axles.

page_text: So
lever C (pivoted at D). This by means of rod E operates the locking bar A.
by rod F, lever G (pivoted at H) the bolt B is drawn out. I prefer to make the
locking bar so that it is on the inside of the rail and is operated slightly ahead of
the bolt as described. The bar A on being operated rises so that if a train is on
the rail above the bar the flange of a wheel of a train prevents anything being
I also
operated and the signalman sees by his repeater that such is the case.
prefer to make the bar so that it rests on a series of rollers R (see Fig. 3), shown
in elevation, which travel on inclined planes P and when it is actuated the rollers R
and bar A travel upwards (but the bar is not thrown over as at present) and when
the bar is up and the bolt is drawn out the points are actuated as described above
for Fig. 1. The points being moved over the circuit to magnet M is broken and
the bar falls down again and the bolt is shot in.
It is obvious that the mechanical details may be arranged in a number of different
ways other than those described. And further it is possible to arrange for the
locking bar to be shot in by a magnet instead of as described. And the locking
bar may be pulled right over and may be in the "four-foot" or otherwise, and it
may be on or attached to rollers or fitted in any convenient way.
It is possible also to fit a large magnet with a cam and gearing which shall
actuate the locking bar and bolt and then pull over the points in one stroke, and
then the bolt and bar be returned to their normal position, and the magnet
circuit broken and the repeater circuit completed.
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 :-
The use of a track circuit in connection with the Patents and improvements
hereinbefore described as and for the purposes hereinbefore described.
. 1000