IMPROVED MEANS AND APPARATUS FOR SECURING SAFETY OF TRAFFIC ON SINGLE LINES OF RAILWAY
Year: 1878

page_text: LETTERS PATENT to Edward Tyer, of No. 4, Old Street, Finsbury, in the
County of Middlesex, for the Invention of "IMPROVED MEANS AND APPARATUS
FOR SECURING SAFETY OF TRAFFIC ON SINGLE LINES OF RAILWAY."
Sealed the 24th May 1878, and dated the 30th March 1878.
PROVISIONAL SPECIFICATION left by the said Edward Tyer at the Office of
the Commissioners of Patents on the 30th March 1878.
EDWARD TYER, of No. 4, Old Street, Finsbury, in the County of Middlesex.
"IMPROVED MEANS AND APPARATUS FOR SECURING SAFETY OF TRAFFIC ON SINGLE
LINES OF RAILWAY."
On single lines of railway it is usual to work the traffic on what is known as the
"staff system," that is to say, for the purpose of preventing collisions no train is
allowed to travel over a section of the line without carrying with it a staff, and as
there is only one staff belonging to the section there can only be one train at a time
on the section. Strict adherence to this system of working often occasions serious
interference with traffic; for instance, a train possessing the staff may be delayed at
a station, and there being no means of conveying the staff to the next station,
the section remains blocked, although traffic might be conducted safely through it.
The object of my Invention is to provide against such impediments to the traffic
of a line, and at the same time to secure the safety obtained by the staff system of
working, and I effect this by a combination of arrangements for the use of the staff,
or an equivalent for the staff, with means of electrically controlling its use, as I will
now describe.
I will suppose that there are two stations, A and B, separated by a section of a
single line of railway, but in electrical communication with one another by a wire,
which may be the wire ordinarily used for block signalling from station to station,
or for controlling from the one station the signals of the other. At each of these
stations I provide two sets of apparatus, one set for up traffic and one set for down
traffic, each set comprising two instruments, one which I may call the receiver, and

page_text: the other the issuer. I provide also a number of portable pieces of metal or other
material, each of which is employed as the equivalent for the staff, that is to say, no
train is allowed to travel over the section without having one of those pieces in its
possession. A convenient form for these pieces is that of a disc with a hole through
it, by which it can be suspended on the locomotive, and it may be marked by a
number or other distinguishing mark for purposes of registration; also, the discs
used for the up traffic are different from or in any convenient manner distinguished
from those used for the down traffic, so that they cannot be employed indis-
criminately.
The receiver, say at station B, consists of a locked receptacle having a double lid,
the upper lid opening upwards and the lower lid opening downwards, and the
hinges of those lids have on them cams engaging with each other in such a manner
that neither lid can be opened except when the other is quite closed. The lower lid
is connected to a catch on an electrical commutator in such a manner that a single
movement thereof disengages the catch, and allows the commutator to be moved
once, and no more, for the purpose of sending a signal to A, the catch re-engaging
when the commutator has been moved to its former position, and remaining co
engaged until the lid is again moved. The movement of the commutator brings
electric contacts into such a position that on a key being depressed at B, clectric
communication is effected with the issuer at A.
The issuer consists of a receptacle which, when discs are employed, is simply an
upright cylinder having a locked lid and a sliding or revolving bottom recessed to
receive one of the discs, and provided with ratchets which are engaged by pawls
connected to the polarised armature of an electro-magnet. The coil of this magnet
is connected to the wire, with which contact is made by the before-mentioned key
at B, and the conductors to the coil are so arranged that the circuit is broken
when the sliding or revolving bottom of the issuer is moved for withdrawal of
a disc.
The receptacle of the issuer at A being charged with a number of the discs, one
above the other, and being locked up, the lowest of the discs lies in the recess of the
moveable bottom, but this bottom being held by the ratchet and pawl cannot be
moved.
The attendant at B is informed from A by ordinary electrical communication that
it is desired to pass a train from A to B. If the section is clear, and if he has his
commutator in proper position, he depresses his key, and the electro-magnet at A
thereupon causes a pawl to be released, so that the attendant at A can move the
bottom of the issuer, drawing it forwards or moving it round so as to bring out the
lowest of the discs sunk in its recess; he gives this disc to the driver of the waiting
train, who proceeds with it to B, and delivers it to the attendant there, receiving
another disc for the next section. The attendant at B raises the upper lid of his
receiver and inserts the disc which he has just received, and closes the lid down
again. When it is quite closed, the lower lid, being released, is borne down by the
weight of the disc lying on it, and opens, allowing the disc to drop into the recep-
tacle below, being closed again by a spring or counterweight. The disc in passing
to the receptacle releases the latch of the commutator, and B can then acknowledge
to A receipt of the disc, thus intimating line clear between A and B; in like manner
the receiver at A acts reciprocally on the issuer at B, and thus the issue of a disc at
each station is completely under the control of the attendant at the next station,
who in his turn is controlled as to the issue of discs, and as two discs cannot be
issued for the same section, no two trains can travel on the same section at the same
time in opposite directions.
To prevent discs for up traffic from being used for down traffic, and conversely, 1
make those for the one with a notch, broad and shallow, and those for the other with
a notch, narrow and deep, and provide in the opening to each instrument a stud or
projection which will fit the one notch but not the other. Thus, supposing the line
to be down from A to B, the attendant at B can only receive down discs from A,
and can only issue up discs when A releases his issuer. At stated periods, as, for

page_text: example, daily, all the down discs received by B are taken back to A's issuer, and
all the up discs received by A are taken back to B's issuer.
It is convenient to apply to each instrument an indicator showing the operator
whether the instrument is in condition to be worked or not.
The electrical circuits of the apparatus may be connected to interlocking gear of
the out-door signals, so that no disc can be issued to allow a train to proceed unless
the signals shew that it may safely do so, and that when a disc has been issued the
signals are locked to the attitude consistent with the dismissal of the train which
has received the disc, and forbidding the advance of a train in the opposite
direction.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edward Tyer in the Great Seal Patent Office on the 23rd September
1878.
EDWARD TYER, of No. 4, Old Street, Finsbury, in the County of Middlesex.
"IMPROVED MEANS AND APPARATUS FOR SECURING SAFETY OF TRAFFIC ON SINGLE
LINES OF RAILWAY."
On single lines of railway it is usual to work the traffic on what is known as the
"staff system," that is to say, for the purpose of preventing collisions no train is
allowed to travel over a section of the line without carrying with it a staff, and as
there is only one staff belonging to the section, there can only be one train at a time
on the section. Strict adherence to this system of working often occasions serious
interference with traffic. For instance, a train possessing the staff may be delayed
at a station, and there being no means of conveying the staff to the next station,
the section remains blocked, although traffic might be conducted safely through it.
The object of my Invention is to provide against such impediments to the traffic
of a line, and at the same time to secure the safety obtained by the staff system of
working, and I effect this by a combination of arrangements for the use of the
staff, or an equivalent for the staff, with means of electrically controlling its use, as
I will now describe.
I will suppose that there are two stations, A and B, separated by a section of a
single line of railway, but in electrical communication with one another by a wire,
which may be the wire ordinarily used for block signalling from station to station,
or for controlling from the one station the signals of the other. At each of these
stations I provide two sets of apparatus, one set for up traffic, and one set for down
traffic, each set comprising two instruments, one which I may call the receiver, and
the other the issuer. I provide also a number of portable pieces of metal, or other
material, each of which is employed as the equivalent for the staff, that is to say, no
train is allowed to travel over the section without having one of these pieces in its
possession. A convenient form for these pieces is that of a disc with a hole through

page_text: it, by which it can be suspended on the locomotive, and it may be marked by a
number or other distinguishing mark for purposes of registration.
The receiver, say, at station B, consists of a locked receptacle having a double
lid, the upper lid opening upwards, and the lower lid opening downwards, and the
hinges of those lids have on them cams engaging with each other in such a manner
that neither lid can be opened except when the other is quite closed. The lower lid
is connected to a catch on an electrical commutator in such a manner that a single
movement thereof disengages the catch, and allows the commutator to be moved
once and no more, for the purpose of sending a signal to A, the catch re-engaging
when the commutator has been moved to its former position, and remaining so
engaged until the lid is again moved. The movement of the commutator brings
electric contacts into such a position that on a key being depressed at B electric
communication is effected with the issuer at A.
The issuer consists of a receptacle, which when discs are employed is simply an
upright cylinder, having a locked lid and a sliding or revolving bottom recessed to
receive one of the discs, and provided with ratchets, which are engaged by pawls
connected to the polarised armature of an electro-magnet. The coil of this magnet
is connected to the wire with which contact is made by the before-mentioned key
at B, and the conductors to the coil are so arranged that the circuit is broken
when the sliding or revolving bottom of the issuer is moved for withdrawal of a
disc.
The receptacle of the issuer at A. being charged with a number of the discs one
above the other, and being locked up, the lowest of the discs lies in the recess of
the moveable bottom, but this bottom being held by the ratchet and pawl cannot be
inoved.
The attendant at B is informed from A by ordinary electrical communication
that it is desired to pass a train from A to B. If the section is clear, and if he has
his commutator in proper position, he depresses his key, and the electro-maguet at
A thereupon causes a pawl to be released so that the attendant at A can move the
bottom of the issuer, drawing it forwards or moving it round, so as to bring out
the lowest of the discs sunk in its reccss. He gives this disc to the driver of the
waiting train, who proceeds with it to B, and delivers it to the attendant there,
receiving another disc for the next section. The attendant at B raises the upper lid
of his receiver and inserts the disc which he has just received, and closes the lid
down again. When it is quite closed the lower lid being released is borne down
by the weight of the disc lying on it and opens, allowing the disc to drop into the
receptacle below, being closed again by a spring or counterweight. The disc in
passing to the receptacle releases the latch of the commutator, and B can then
acknowledge to A receipt of the disc, thus intimating line clear between A and B.
In like manner the receiver at A acts reciprocally on the issuer at B, and thus the
issue of a disc at each station is completely under the control of the attendant at
the next station, who in his turn is controlled as to the issue of discs, and as two
discs cannot be issued for the same section, no two trains can travel on the same
section at the same time in opposite directions.
To prevent discs for one section from being used for another section those for
the one may be inade with a notch broad and shallow, and those for the other with
a notch narrow and deep, a stud or projection being provided in the opening to
each instrument which will fit the one notch but not the other.
It is convenient to apply to each instrument an indicator, shewing the operator
whether the instrument is in condition to be worked or not.
The electrical circuits of the apparatus may be connected to interlocking gear of
the outdoor signals, so that no disc can be issued to allow a train to proceed unless
the signals shew that it may safely do so, and that when a disc has been issued
the signals are locked to the attitude consistent with the dismissal of the train
which has received the disc, and forbidding the advance of a train in the opposite
direction.

page_text: DESCRIPTION OF THE DRAWINGS.
Fig. 1 represents a longitudinal section of what I have above termed the receiver
or apparatus for the reception of the staff discs; Fig. 2 is a plan of the gearing;
and Fig. 3 is a front view of the indicating portion of this apparatus; Fig. 4 is a
front view; and Fig. 5 is a section of one of the discs employed in lieu of the staff,
each of these discs being conveniently made with an undercut recess in its face, in
which is pasted or glued a disc of paper or parchment, with a number and names
to distinguish the section on which it is issued, a hole being provided through it,
by which it can be hung on a hook on the locomotive when in use.
A is the receiving box having an upper lid a', which can be raised by hand for
the introduction of one of the discs D, and having a lower counterweighted lid a²,
which, by the weight of the disc when laid upon it, descends to the dotted
position a³, and allows the disc D₁ to slide off it into a locked receptacle below,
which may be in the form of a bag, as partly shown at B, or which may itself bo
the receptacle of the other apparatus, which will be hereafter described, and which
I have termed the issuer.
The two lids a¹, a², have near their respective pivots can surfaces c³, c², 80
arranged that neither lid can be opened unless the other is closed, and consequently
when a disc D has been placed in A it remains there till the lid al is closed down.
When this is done the lid a² opens downwards, locking the lid a¹ down, and not
until a las discharged its disc into the locked receptacle and has been caused by
its counterweight to close again upwards can the lid a' be again opened.
The lid a² by means of an arm E on its spindle works a rod e connected to a
lever F, the upper end of which forms a catch for either of two studs fl on the
face of a mitre wheel G. This wheel is fixed on a spindle H, which can be turned
in one direction (as indicated by the arrow, Fig. 1) by a knob h, a ratchet and
pawl preventing it from being turned in the opposite direction. On the spindle H
there is also fixed a disc I, having in its edge four equidistant notches, into any
one of which catches a stud on a spring lever i that can be depressed by a plunger
rod . There is also fixed on the spindle H a commutator J, which in the usual
way makes and breaks electrical contacts for the poles of a battery, the line wire
and earth according as it is turned round into one or another attitude. The
wheel G gears with another mitre wheel G', on the axis of which is a disc g in four
divisions, two of which are marked with the word OUT, and two with the word
IN, or with words of equivalent meaning. The one or the other of these words is
seen through a hole g' in the front of the apparatus, according as the disc is turned
round. is a spring stop with wedge piece in the middle to ensure the complete
stroke of the lever F; and f is a lever, one end of which bears on the pin f¹, the
other end catching against the top of the lever F.
The action of this apparatus is as follows:-The operator having raised the lid a¹
inserts in A the disc D which rests on a²; he then closes a¹, and the lid a² there-
upon descends, delivering the disc D into the receptacle below, and by its descent
moving the lever F so that its hooked head is withdrawn from the course of one
of the pins f¹. The attendant can now by pressing down the plunger ¹ release the
disc I, and by means of the knob h he turns the spindle H one quarter round till
the stud on i again catches in a notch of I, the disc g now shewing the word IN
through the front hole, and the commutator J being in position for sending an
electrical signal to the distant station. This signal is sent by the attendant pressing
in the plunger L in the usual way. As the pin fl passes the lever fit raises it,
causing its opposite end to push in the hook of the lever F so as to be ready to catch
the other pin f' when the spindle is again turned. Thus the instrument cannot
again be worked till another disc is introduced into the receptacle. The signal sent
by the pressure of L permits the attendant at the distant station to make the first
movement for the purpose of issuing a disc, as will be presently described. Having
done so be signals to the attendant at the receiver, who then turns the spindle й

page_text: another quarter round, and this on the key L being pressed permits the attendant
at the issuer to issue a disc. The receiver then remains locked till this disc be
received, that is to say, till the section of line is clear of the train to which the said
disc was issued.
Fig. 6 is a longitudinal section of the issuer or apparatus for issuing the discs,
Fig. 7 being a front view of the indicator of ordinary construction, which is con-
nected to it.
M is a cylindrical receptacle containing a number of the discs D lying one abovo
another; N is a slide recessed the depth of one of the discs. On this slide are two
ratchet racks n, side by side, having their teeth directed opposite ways, and engaged
respectively by pawls p, p', which are worked by the polarised armature o of an
electro-magnet O. As shown in the Figure, the pawl p being in gear with its rack
the slide N cannot be pulled out, but if by an electrical current sent from the distant
station the polarity of the magnet O be reversed, then will be raised out of gear
and the slide N with the lowest of the discs in its recess can be drawn out. This
disc can then be removed from the slide and given to the driver of a train. As the
pawl 2 is now in gear with its rack the slide cannot be pushed in again until the
polarity of O is again changed by a current from the distant station, whereupon N
can be pushed in, but p being again in gear it cannot be drawn out to issue another
disc until permission is given, as above described, from the distant station. The
indicator shows the operator, whether the disc he has issued has been received or
not, its indications corresponding with the condition of the pawls 2, p².
Although I have described the slide N as working to and fro rectilineally, it
obviously could be arranged to rotate under the cylinder M either always in one
direction step by step, with several successive recesses for discs, or it might be a
segment of a disc working to and fro on a centre. Also, though I have described
the circular disc as a convenient form of substitute for the staff, it may be readily
understood that pieces of metal, wood, or other suitable material of different forms
might be employed with means, such as I have described, for controlling their use
by rendering their issue at one station dependent on their receipt at another.
Having thus described the nature of the said Invention, and in what manner the
same is to be performed, I claim,—
First. The method, substantially as herein described, of controlling the traffic on
n section of railway by the use of discs or their equivalents, the issue of which to a
train at one station is not permitted except by electrical communication from
another station, the said communication being possibly only when the disc last issued
from the former station has been received at the latter station.
Second. The use for operating, in the manner referred to in the preceding claim,
of apparatus constituting a receiver constructed and working, substantially as herein
described with reference to Figs. 1, 2, and 3 of the accompanying Drawings.
Third. The use for operating in the manner referred to in the first claim, of
apparatus constituting an issuer, constructed and working substantially as hercin
described with reference to Figs. 6 and 7 of the accompanying Drawings.
In witness whereof, I, the said Edward Tyer, have hereunto set_my_hand
and seal, this Second day of September, in the year of our Lord One
thousand eight hundred and seventy-eight.