Improvements in Apparatus for Securing Safety of Traffic on Single Lines of Railway.
Year: 1888

page_text: Date of Application, 2nd Jan., 1888,
Complete Specification Left, 29th Sept., 1888
Complete Specification Accepted, 9th Nov., 1888
Improvements in Apparatus for Securing Safety of Traffic on Single
Lines of Railway.
I, EDWARD TYER of Ashwin Street, Dalston, London, Electrical Engineer do
hereby declare the nature of this invention to be as follows:-
In my Specification No. 1262 of 1878 i described means of securing safety of
traffic on single lines of railway by employing, instead of the staff which in such
cases trains are obliged to carry with them, a metallic or other disc or tablet which is
issued to the train at one station and deposited at the next, the issue of every such
tablet at the one station being determined by apparatus controlled electrically from
the other station. My present invention relates to apparatus for this purpose arranged
in a simplified manner so that it can be worked with more ease and certainty than the
apparatus described in my previous Specification.
Assuming that there are two stations Y and Z separated by a section of the line in
electrical communication by a wire such as is ordinarily used for telegraphic block
signalling, I provide at each of the stations an apparatus which serves as a receiver of
the discs brought to the station by trains arriving and an issuer of discs to trains
departing.
This apparatus has, in the first place, a receptacle for a number of the discs or
tablets in the form of a vertical cylinder having a sliding bottom that can be raised
or lowered by a hand screw. Over this receptacle is fitted a sliding plate having
through it a hole of such size as to hold one of the tablets in a horizontal position.
The operator by means of the screw can raise the tablets in the receptacle until the
uppermost tablet occupies the hole in the sliding plate or he can lower the tablets
so that the hole in the plate is left vacant. On the cover which is fixed over the
sliding plate is a guage which shews through a glass lid whether a tablet is in the
hole of the plate or not. The sliding plate can be drawn out so as to present the hole
in it, either containing a tablet which can be issued to a train, or empty for the
reception of a tablet brought by a train.
The movements of the sliding plate are governed by certain pawl catches, one
which prevents the slide from being drawn out without a tablet. another which prevents
it from being drawn out empty, or pushed in with or without a tablet. Each of these
catches can be released by the movement of the armature of an electromagnet excited
by a current from a local battery. The one magnet is brought into action by the
transmission of a positive electrical current from the distant station, the other by the

page_text: transmission of a negative current, the transmitted current in either case acting on
a polarised relay by which the local circuit of the one or the other electromagnet is
closed. The movements of the sliding plate also make or break contacts and lock or
unlock a commutator handle which can be turned into one or other of two positions.
When it is in the one position the operator can, by means of a spring plunger sliding
through the commutator handle, transmit only positive currents to the distant station,
when it is in the other position he can transmit only negative currents. To the
commutator handle is attached a screen which shews through a glass in the one position
the word "out" and in the other position the word "in."
Above this screen there is arranged in the casing the polarized relay which is acted
on by currents from the distant station, and which operates for making contacts for
the local circuits of the electro magnets and for a local circuit for sounding a bell
or gong:
In this relay there is an electromagnet with its polarised armature which, when a
number of impulses are transmitted from the distant station closes the one local circuit
through an electro magnet fitted with an armature hammer for the purpose of sounding
the bell or gong. This armature at the same time works a striker which makes a
contact for the other local circuit by striking a plate free to vibrate. When the
impulse is only momentary or when there is a succession of momentary impulses, the
vibration of the plate does not give time for this local circuit to be effectively closed,
but when the current from the distant station is maintained for a few seconds so that
the vibrating plate has time to come to rest against its striker, the local circuit is
closed for the one or other of the two electro magnets which work the catches of the
sliding plate. The choice of these two circuits is determined by the attitude of the
polarized armature which is caused by the electro magnet of the relay to take the one
position or the other according as a positive or a negative current is transmitted from
the distant station, and this position is shewn by a screen seen through a glass
presenting the word "out" or "in" as the case may be. There is also a galvano-
meter needle worked by the currents from the distant station, which indicates the
passage of each signal between the two stations, and also the condition of the local
circuits. Such being generally the construction and arrangement of the apparatus, a
complete set of which is provided at each of the two stations Y and Z, the operation
of the signalmen at these stations is conducted in the following manner. Y having a
train ready to enter the section towards Z, calls Z by several preconcerted movements
of his signalling plunger, causing several strokes on the bell or gong as a preparatory
signal; to this Z replies by repetition of the same signal. Y then signals by another
preconcerted number of strokes that he wishes to issue a tablet, and Z acknowledges
by repetition of this signal. Y then holds in his signalling plunger until he sees
galvanometer needle come to zero, this shewing him that Z has fully drawn out his sliding
plate and turned his commutator so that instead of "in" it shows "out." Y then lets
go his plunger and Z holds in his for several seconds which will cause release of Y's
slide as indicated by the word "out" appearing on the upper screen belonging to his
polarised relay. Y then draws out his slide and taking the tablet from
his
gives it to
the departing train, and he thereupon signals to Z the departure of the train. On the
arrival of the train at Z's station, Z receives the tablet, places it in his slide and
signals the arrival of the train to Y who first acknowledges the signal and then holds
his plunger in until his galvanometer needle comes to zero. This permits Z to turn
his commutator to shew in" and to signal "in" to Y who then pushes in his slide
and signals "in" to Z. In a similar manner the issue and reception of tablets is
controlled throughout the several sections of the line, and each apparatus, being
capable of alternative action either for issue or reception, serves for trains in both
directions.
15

page_text: Single Lines of Railway.
I, EDWARD TYER, of Ashwin Street, Dalston, London, Electrical 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:
In my Specification No. 1262 of 1878 I described means of securing safety of
traffic on single lines of railway by employing, instead of the staff which in such cases
trains are obliged to carry with them, a metallic or other disc or tablet which is
issued to the train at one station and deposited at the next, the issue of every such
tablet, at the one station being determined by apparatus controlled electrically from
the other station.
My present invention relates to apparatus for this purpose arranged in a simplified
manner so that it can be worked with more ease and certainty than the apparatus
described in my previous Specification.
Assuming that there are two stations Y and Z separated by a section of the line, in
electrical communication by a wire such as is ordinarily used for telegraphic block
signalling, 1 provide at each of the stations an apparatus which serves as a receiver
of the discs brought to the station by trains arriving and an issuer of discs to
trains departing. This apparatus has, in the first place, a receptacle for a number
of the discs or tablets in the form of a vertical cylinder having a sliding bottom
that can be raised or lowered by a hand scrow. Over this receptacle is fitted :1
sliding plate having through it a hole of such size as to hold one of the tablets
in a horizontal position.
The operator by means of the screw can raise the tablets in the receptacle until the
uppermost tablet occupies the hole in the sliding plate; or he can lower the tablets
so that the hole in the plate is left vacant. On the cover which is fixed over the
sliding plate is a gauge which shews through a glass lid whether a tablet is in the
hole of the plate or not. The sliding plate can be drawn out so as to present the hole
in it, either containing a tablet which can be issued to a train, or empty for the
reception of a tablet brought by a train.
The movements of the sliding piate are governed by certain pawl catches, one
which prevents the slide from being drawn out without a tablet and the other which
permits the slide to be drawn out empty or to be pushed in with or without a
tablet.
Each of these catches can be released by the movement of the armature of an
electro magnet excited by a current from a local battery. One of the magnets is
brought into action by the transmission of a positive electrical current from the distant
station, the other by the transmission of a negative current, the transmitted current
in either case acting on a polarised relay by which the local circuit of the one or the
other electromagnet is closed.

page_text: The movements of the sliding plate also make or break contacts and lock or unlock
a commutator handle which can be turned into one or other of two positions. When
it is in the one position the operator can, by means of a spring plunger sliding through
the commutator handle, transmit only positive currents to the distant station, when it
is in the other position he can transmit only negative currents. To the commutator
handle is attached a screen which shews through a glass in the one position the word
"out" and in the other position the word "in.'
Above this screen there is arranged in the casing the polarised relay which is acted
on by currents from the distant station, and which operates for closing the local
circuits of the electromagnets and also a local circuit, for sounding a bell or gong.
In this relay there is an electromagnet with its polarised armature which, when a
number of impulses are transmitted from the distant station, closes the one local
circuit through an electric magnet having an armature hammer to sound the bell or
gong. This armature at the same time works a striker which makes a contact for the
other local circuit by striking a plate free to vibrate. When the impulse is only
momentary or when there is a succession of momentary impulses the vibration of the
plate does not give time for this local circuit to be effectively closed, but when the
current from the distant station is maintained for a few seconds so that the vibrating
plate has time to come to rest against its striker, the local circuit is closed for the
one or the other of the two electro magnets which work the catches of the sliding
plate.
The choice of these two circuits is determined by the attitude of the polarised
armature which is caused by the electro magnet of the relay to take the one position
or the other according as a positive or a negative current is transmitted from the
distant station, and this position is shown by a screen seen through the glass presenting
the word "out" or "in" as the case may be. There is also a galvanometer needle,
worked by the currents from the distant station, which indicates the passage of each
signal between the two stations, and also the condition of the local circuits. Such
being generally the construction and arrangement of the apparatus, a complete set
of which is provided at each of the two stations Y and Z, the operation of the
signalmen at these stations is conducted in the following manner. Y having
a train
ready to enter the section towards Z, calls Z by several preconcerted movements of
his signalling plunger, causing several strokes on the bell or gong as a preparatory
signal; to this Z replies by repetition of the same signal. Y then signals by another
preconcerted number of strokes that he wishes to issue a tablet, and Z acknowledges
by repetition of this signal. Y then holds in his signalling plunger until he sees his
galvanometer needle come to zero, this shewing him that Z has fully drawn out his
sliding plate and turned his commutator so that, instead of "in," it shews "out."
Y then lets go his plunger and Z holds in his for several seconds which will cause
release of Y's slide as indicated by the word "out" appearing on the upper screen
belonging to his polarised relay. Y then draws out his slide, and taking the tablet
from it, gives it to the departing train, and he thereupon signals to Z the departure of
the train. On the arrival of the train at Z's station, Z receives the tablet, places it in
his slide and signals the arrival of the train to Y who first acknowledges the signal
and then holds his plunger in until his galvanometer needle comes to zero.
permits Z to turn his commutator to shew "in" and to signal "in" to Y who then
pushes in his slide and signals "in" to Z. In a similar manner the issue and
reception of tablets is controlled throughout the several sections of the line; and each
apparatus, being capable of alternative action either for issue or reception, serves for
trains in both directions.
This
Such being the nature of my invention and the mode of operating with it, I will
now describe more particularly the construction and arrangement of the apparatus
which employ, referring to the accompanying drawings.
As shewn in the perspective view Fig. 1, the apparatus consists of a base portion A
containing the mechanism for introduction and removal of the discs, and an upright
back part B containing the signalling mechanism, above which, but it may be separate
from it, as shewn, is an electric bell or gong C. Of the base portion A Fig. 2 is a

page_text: side view and Figs. 3 and 4 are plans, Fig. 3 shewing the sliding plate in, and
Fig. 4 shewing it pulled out to receive a disc such as is shewn by Fig. 5. The back
or signalling portion B of the apparatus is shewn in Figs. 6 to 10 inclusive, Fig. 6
being a front view of its hinder side, Fig. S a side view, Fig. 9 a plan and Fig. 10 a
sectional plan on X X of Fig. 8. The general arrangement of the electrical contacts
and connections is shewn diagrammatically by Fig. 11.
Referring first to Figs. 2, 3.4, and 5, a number of the discs D are piled upon one
another in a cylindrical case E resting on the top of a bracket e which passes through
a vertical slot in the back of the case E and can be raised or lowered by turning a
screw e by a hand wheel e².
A sliding plate F has through it a hole to receive one of the discs D when the
plate is pushed in so as to bring the hole immediately over the case E.
When by
turning the screw el the uppermost of the discs D is raised so as to occupy the hole f
a bent arm e³ which rests on the disc raises an index et within a casing e, and the
operator, by seeing the index raised to the level of the top of its case e, knows that
a disc is in the hole in proper position for the slide F to be drawn out bringing
the disc with it. The bent arm e projects from a rocking spindle e which has other
arms that control a pair of pawl levers f¹ and as shewn in the separate views Figs. 2*
and 2. Thus an arm on the spindle has a pin which when the arm e³ finds no
dise D under it holds up the lever preventing it from dropping into a slot of the
slide F. When however the arme has a disc D under it at the proper height,
another arm of the spindle bearing on the tail of the pawl lever prevents it
from dropping into a slot of the slide F. Under the frame are fixed the electro-
magnets G², only one of which G2 is seen in Fig. 2. When either of these is
excited by a current of electricity its armature is attracted, and the upper end of the,
armature lever acting on a pin of the pawl lever for f raises it out of the slot of
the slide F.
Thus when the magnet G¹ is excited the sloped end g' of its armature lover moving
under a pin off raises f"; and in like manner, when G2 is excited, the sloped end g
of its armature lever raises/. While the pawl levers are engaged in the slots
of the slide F, the slide is held, and can only be moved to and fro when its slots are
released from the pawl levers or from that one of them which for the time is
holding the slide.
The electromagnets G1 G2, as already described, are excited by currents from a local
battery which are brought into circuit with the one or the other of the magnets
according as a positive or a negative electrical impulse is transmitted from a distant
station; consequently the movements of the slide F are thus controlled from the
distant station.
A bar H having fixed on it inclines is jointed to a slide h which projects
down into a slot of the slide F and is itself slotted for the passage of the screw el
through it. At each end of the stroke of the slide F, the slide is moved a little,
altering the position of the inclines relatively to the indicating apparatus, on
which they operate as will hereafter be described. To the slide is also jointed an
arm having its under face e shaped as an obtuse wodge which lies in the hole of the
uppermost disc D but rises to allow the disc to be moved with the slide F. On the
upper face of the arm is a catch e which can engage with a catch on the arm e³ in
case that arm should drop too low down owing to the absence of a disc below it, and
the engagement of those catches in that case prevents the slide h from being moved
quite back and the slide F from being pushed quite in.
Besides the pawl levers worked by the electromagnets G G as above
described, there is a third paw! lever which, as shewn in Fig. 2 is usually held
up by a catch on the armature lever gl and by a block fixed on the slide F.
But, when the head g of the armature lever is moved to the left raising and
releasing the pin on then if the slide be moved to the left withdrawing the
block, the lever is left free and finally drops into a slot of the slide F and
so prevents the slide from being drawn fully out. This however happens only when
the slide is released by the raising of the pawl lever f' that is to say when there is

page_text: a disc in the hole of the slide F, the presence of the disc acting on e³ eª ƒ¨³ and ƒª
so as to make the active pawl and f the inert pawl.
When however there is no disc in the pawl is inert, and it is by the lifting
of that the slide F is released. In this case, as the release is not effected by the
movement of the armature lever g¹ the pawl f remains beld up and the slide F is not
stopped by it before the end of its stroke.
The effect therefore of the arrangement of pawls described is that when there is a
disc under e³, on the excitement of G' raising f¹ the slide F can be drawn out with
the disc, not to its full extent but sufficiently far to allow the disc to be taken out,
that on the excitement of G2 raising the slide F can be pushed in. Again on the
excitement of G³ the slide F can be fully drawn out to receive a disc with which it
can be pushed in. If in this case it has no disc it cannot be pushed in to its full
extent, the catches ese coming then into operation; and finally that when there is no
disc in the slide, the excitement of G2 raising allows the slide to be fully drawn out
to receive a disc. Referring now to Figs. 6 to 11 inclusive representing the indicating
portion B of the apparatus, there is in front of the case a commutator handle K
with a spring contact plunger passing through it, on pushing in which plunger
contacts are made at these contacts depending on whether the handle K is
turned a little round in the one direction or the other. The turning of this handle is
controlled by the inclines h² on the bar H according as the slide F is pushed in or
drawn out. When the slide is pushed in, the incline on H coming under an arm ³
(Fig. 7) lifts it and thereby releases from a catch a pin which is on an arm extending
down from the commutator handle K, and this handle can then be turned until the
pin becomes engaged with a catch on another arm which catch holds it and
prevents the commutator handle K from being turned backwards.
22
When however the slide F is drawn out, the other incline on the bar H coming
under * raises it and releases the pin h. To the handle K is attached a screen ¹
which presents through a glass either the word "in or the word " out" according as
the handle K is turned to the one attitude or the other as determined by the position
of the inclines ¹² on the bar H. On the arm which carries the pin 5 there is fixed
a block of insulating material which when the commutator is turned so as to
present the word "out"
on its screen pushes into contact two springs k³, these
springs being out of contact when the commutator screen shews the word "in."
Again there is fixed on the slide F a raised path on which run insulated rollers h
(Fig. 8) or off from which they run as the slide F is moved to and fro.
On the slide F is pivotted a horizontal lever which when its tail meets the pawl
lever fon pulling out the slide F is prevented from turning on its pivot so that its
bent end being held over the path 6, as shewn in Fig. 3, the roller is raised as the
end of passes under it, and a contact is made at which closes the line circuit that
had been opened by the partial raising of the roller as the lower portion of the
path passed under it.
When the slide F is pushed in, the lever f meets a stop (shewn in dotted lines
at Fig. 10) which turns it on its pivot away from the part of the raised path 76 where
it would raise the roller . These rollers as they are raised by travelling on the
raised path 76 or as they are lowered when the raised path passes from under them,
make or break contacts by pressing springs 8 h together or releasing them.
At L there is an electromagnet which performs two functions; it moves a polarised
armature carrying a screen, to right or left according as the magnet is excited by
a current of the one or the other direction, and it also moves the polarised armature of
a relay 2 causing it to make contacts on the one side or the other as determined by
12
the direction of the current which excites the magnet L. The screen presents
through a glass in the front of the case the word "in" or "out" according as it is
moved to the one side or the other. The relay serves to close the circuit for the one
or the other of the electromagnets G G with a local battery M. A galvanometer N
presents itself at the front of the case in its upper part, and above the case is the
electric bell or gong apparatus C the construction of which is shewn more fully at Cin
Fig. 11. To its vibrating armature c is jointed a rod c¹ which oscillating with the

page_text: armature strikes one arm of a double armed swinging piece c² the lower arm of which
is heavier than the upper arm. Should the rod c give only a momentary blow to the
arm of cor a rapid succession of such blows, there is not sufficient duration of contact
between c¹ and c³ for passage of a current; but should the rod c¹ dwell for a little
time in contact with the arm of c², a current is transmitted. The diagram Fig. 11
shews the electrical connections of the various parts described with the local battery M
and with the line and earth wires by which the operator makes communication
with the distant stations, either when he pushes in the plunger of his commutator K
thereby acting on the contacts at k or when he moves his slide F thereby acting on
the contacts at ; and by which the operator receives communications from the distant
stations by the excitement of the electro magnet L moving the screen and acting on
the relay thereby bringing the bell apparatus C, the galvanometer N, and the one
or other of the electromagnets G G2 into circuit with the local battery M.
Having now particularly described and ascertained the nature of this invention and
in what manner the same is to be performed, I declare that what I claim in respect
of apparatus for securing safety of traffic on single lines of railway is :-
1. The combination of the case E holding discs D, the slide F, the electro-
magnets GG, and the pawl levers operated by them, substantially as described.
2. The combination of the slides F and h, the bar H having inclines ¹², the
arms and the commutator K with its pin and screen arranged so that the
position of the commutator is controlled by that of the slide F, substantially, as
described.
Dated this 29th day of September 1888.
ABEL & IMRAY,
Agents for the Applicant.