IMPROVE. MENTS IN BLOCK SIGNALLING ON RAILWAYS, AND IN APPARATUS CONNECTED PROVISIONAL
Year: 1881

page_text: LETTERS PATENT to John William Fletcher, of 93, Chatham Street, Stockport;
in the County of Chester, Telegraph Engineer, for an Invention of "IMPROVE.
MENTS IN BLOCK SIGNALLING ON RAILWAYS, AND IN APPARATUS CONNECTED
PROVISIONAL SPECIFICATION left by the said John William Fletcher at
the Office of the Commissioners of Patents on the 26th April 1881.
JOHN WILLIAM FLETCHER, of 93, Chatham Street, Stockport, in the County of
"IMPROVEMENTS IN
Chester, Telegraph Engineer.
BLOCK SIGNALLING ON
RAILWAYS, AND IN APPARATUS CONNECTED THEREWITH."
My said Invention relates to working signals in connection with shunting
stations or sidings situated in advance of an ordinary or block signal box, and has
reference more particularly to shunting stations or sidings at such a distance from
the signal box as to be out of sight of the signal man, and too far away for the
points to be operated by a lever in the said signal box.
.
Hitherto it has been customary to lock the shunting points and leave the key in
charge of the signalman in the box next behind the shunting station or siding,
the said key being used to lock the signal at danger before unlocking the points,
and being returned to the signal man after the completion of the shunting operations
and the locking of the points. The above practice entails great loss of time owing
to the guard or other attendant having to travel back to the signal box after the
shunting is completed and then return to the train before it may proceed.
Now the main objects of my Invention are to enable shunting to be effected
with safety and without risk to advancing trains, and to permit the shunting train
to depart from the siding without the necessity of an attendant travelling to
the signal box and back again, thus reducing the time required for shunting, and
allowing of a greater number of trains passing the said signal box.
My system of signalling consists in so combining the signal and the shunting
points when worked by separate levers at distances apart that the signal shall be
in the position indicating danger when the points are open or in position to allow
of the siding being used, and shall not be capable of alteration without the consent

page_text: of the attendant at the shunting station or siding, and further that the points at
the shunting station or siding shall be locked so that they cannot be moved without
the consent of the signalman.
In carrying my Invention into practice the lever in the signal box which works.
the signal, and the lever at the shunting station or siding which actuates the
points, are each fitted with locking apparatus of any desired kind capable of being
operated by an electric current. The said locking appliances are so arranged that
when the signal lever is free to be moved the points lever is locked in closed
position, and that when the points are free to be moved the signal lever is locked
in position to maintain the signal at danger. The said locking appliances are put
into operation by means of keys, studs, or push pieces in the signal box and at the
shunting station or sliding.
The action of the apparatus is as follows:-
When a train arrives at the signal box and it is desired to use the siding, notice
is given to the signal man, who places the signal at danger and then presses the
stud or push piece; an electric circuit is thereby completed, the signal is locked at
danger, and the points are freed. After the shunting has taken place and the
train is ready to proceed the points at the shunting station are closed, and
the key, stud, or push piece pressed. The electric circuit is now broken, the points
locked in closed position, and the signal freed so as to be under the control of the
signal man.
It will be evident that the closing of the points at the shunting siding may
operate the key, stud, or push piece above mentioned, or that the points themselves
may serve as contact makers and breakers to complete and break the circuit-for
the electric current controlling the position of the locking appliances.
Fluid pressure may be used as the operating agent for the locking appliances or
devices.
When there are two or more sets of shunting points they are each interlocked
with the signal, substantially as above set forth.

page_text: "
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John William Fletcher in the Great Seal Patent Office on the
25th October 1881.
JOHN WILLIAM FLETCHER, of Stockport, in the County of Chester, Engineer.
IMPROVEMENTS IN BLOCK SIGNALLING ON RAILWAYS, AND IN APPARATUS
CONNECTED THEREWITH."
My said Invention relates to working signals in connection with shunting
stations or sidings situated in advance of an ordinary or block signal box, and has
reference more particularly to shunting stations or sidings at such a distance from
the signal box as to be out of sight of the signal man, and too far away for the
points to be operated by a lever in the said signal box.
Hitherto it has been customary to lock the shunting points and leave the key
in charge of the signal man in the box next behind the shunting station or siding,
the said key being used to lock the signal at danger before unlocking the points,
and being returned to the signal man after the completion of the shunting
operations and the locking of the points. The above practice entails great loss of
time owing to the guard or other attendant having to travel back to the signal
box after the shunting is completed and then return to the train before it may
proceed.
Now the main objects of my Invention are to enable shunting to be effected with
safety and without risk to advancing trains, and to permit the shunting train to
depart from the siding without the necessity of an attendant travelling to the
signal box and back again, thus reducing the time required for shunting, and
allowing of a greater number of trains passing the said signal box.
My system of signalling consists in so combining the signal and the shunting
points when worked by separate levers at distances apart that the signal shall be
in the position indicating danger when the points are open or in position to allow
of the siding being used, and shall not be capable of alteration without the consent
of the attendant at the shunting station or siding, and further that the points at
the shunting station or siding shall be locked so that they cannot be moved without
the consent of the signalman.
In carrying my Invention into practice the lever in the signal box which works
the signal, and the lever at the shunting station or siding which actuates the points,
are each fitted with locking apparatus of any desired kind capable of being operated
by an electric current. The said locking appliances are so arranged that when the
signal lever at the station is free to be moved the points lever at the siding is
locked in closed position, and that when the points are free to be moved the signal
lever is locked in position to maintain the signal at danger. The said locking
appliances are put into operation by means of keys, studs, or push pieces in the
signal box and at the shunting station or siding.
The action of the apparatus is as follows:-
When a train arrives at the signal box and it is desired to use the siding, notice
is given to the signal man who places the signal at danger and then presses or
moves key, stud, or push piece, an electric circuit is thereby completed or broken,
the signal is locked at danger, and the points are freed. After the shunting has
taken place and the train is ready to proceed the points at the shunting station are
closed, and the key, stud, or push piece used. The electric circuit is now broken or
completed, the points locked in closed position, and the signal freed so as to be.
under the control of the signal man.
It will be evident that the closing of the points at the shunting siding may

page_text: operate the key, stud, or push piece above mentioned, or that the points themselves
may serve as contact makers and breakers to complete and break the circuit for the
electric current controlling the position of the locking appliances.
Fluid pressure may be used as the operating agent for the locking appliances or
devices.
When there are two or more sets of shunting points they are each interlocked
with the signal, substantially as. above set forth..
DESCRIPTION OF THE DRAWINGS.
Figs. 1 and 2 are views illustrative of my method of and apparatus for block
signalling in connection with shunting stations or sidings. Fig. 1 represents the
main line signal lever, and Fig. 2 the siding or points levor and accessories. The
lever a, which may be of any usual or desired construction, is connected to
and is used to raise and lower the semaphore of the signal guarding the line
on which the siding or shunting station is situated. The said lever a is provided
with the usual or any suitable locking device b; c, electro magnet attached
to a frame carried by the lever a; d, armature pivotted at e and formed at
one end with the hook or catch f; the other end g of the armature is connected
to the spiral spring ; any other suitable spring may be used secured to the stud i;
j, bell crank lever pivotted at %; l, stud on the rod m of the locking device b.
The lower arm of the lever j rests on the stud l; m, wire from battery B to electro
magnet c; wire from electro magnet c on signal box lever to electro magnet o on
siding or shunting station lever p; q, wire from electro magnet o to earth E, the
battery at signal station end being also connected to carth E. The points lever pat
the siding or shunting station is provided with locking mechanism ; s, armature;
t, hook or catch; u, pivot; v, spiral spring; w, bell crank lever provided with
hook or catch; y, stud on the rod of the locking mechanism ?.
On examination of Fig. 1 it will be seen that the armature d is in its normal
condition when an electric current is not passing, raised from the electro magnet c
by the action of the spiral spring m; bell crank lever j is free, and the locking
device is movable at pleasure. Under the above conditions the lever a may be
moved backwards or forwards, and the main line signal semaphore raised or lowered
as required.
On reference to Fig. 2 it will be seen that the armature s is also raised from the
electro magnet when no current is passing, but that, unlike Fig. 1, the armature
when in the normal or raised position locks the bell crank lever w, and prevents
the locking mechanism being moved on account of the lower arm of the said
lever wresting on the study. The points at the shunting station therefore
cannot be moved.
The action of the above apparatus in carrying into effect my method of signalling
is as follows: When it is desired to use the points, the signal man moves his lever
so as to raise the main line semaphore. With the lever in the above position, the
key stud or push piece 1 is uncovered and is pressed by the signal man to complete
an electric circuit through the magnets c and o. The armatures d and s are thereby
drawn and held down to the poles of the said magnets, so as to lock the lever j
and leave the lever w free. The key stud or push piece 1 may conveniently be
made to act directly on the armature d, as shown, the electric current being
completed when the armature d' and lever ware in contact. When the shunting
operations are finished, the man at the shunting station moves the lever P into
position to open the main line and close the siding. The key stud or push piece 2
disclosed by the motion of the lever is pressed by the pointsman, and the electric
circuit is broken. As soon as the circuit is broken, the armature s is raised by the
spring n and the bell crank lever is locked, the armature d is also raised and
the bell crank lever j freed. The rising of the armature & permanently breaks
the circuit until the stud 1 is again depressed; 3 is a guard plate to prevent the

page_text: key 1 being depressed except when the lever a is in the position shown. The
electro magnets c, o, and locking mechanism connected therewith, are cased or
covered in.
Figs. 3 and 4 are side elevations of so much of signal cabin and siding or
shunting levers as is necessary to illustrate a modification of apparatus under my
Invention, in which an electric current flows continuously through the wire
between the signal cabin and siding or shunting station, except when the siding is
being used. This arrangement of apparatus prevents any accident through failure
of the electric current by breaking of a wire or otherwise, as in such case the main
line signal will be locked at danger, and will so remain until the defect is
repaired.
On reference to the electrical locking mechanism, Figs. 3 and 4, it will be seen
that the arrangements are the reverse of those described under Figs 1 and 2,
namely, that whilst the electric current is passing the lever j of the signal box is
free and the lever w of the shunting or siding station is locked, and that when
the current is broken the lever j of the signal cabin is locked and the lever w of
the shunting station freed. The lever j in this case is arranged to act on locking
mechanism 4 of well known construction. The mechanism 4 is operated by means
of a square key acting in the hole 5. 6 are two contact makers (one only may be
used), to which the wire n from the electro magnet c is attached; the said wire
thence passes, if desired, through needle indicators 7 in the signal cabin, and 8 at
the siding or shunting station; from 8 the wire passes through the electro magnet o,
then through the contact makers 9 to earth, the battery 10 being also connected
to earth. The circuit through the indicator 8 is completed through an electro
magnet and armature, arranged in a manner similar to that described in reference
to c, d, Fig. 1. 1, key or push piece.
The action of the apparatus is as follows:-The signalman puts his main line
signal to danger, he is then able to insert his key in the hole 5 and lock the signal
in the usual manner; in turning the key the contact makers 6 are separated and
the circuit is broken, the breaking of the circuit causes the magnet in 8 to lose its
attractive force, the armature is moved away from the poles of the magnet by a
spring, and the circuit is permanently broken until the stud 1 is turned, and the
armature moved to its original position. When the key in the hole 5 is turned
the required distance or is reversed the contact makers close the circuit at 5, but it
is still broken at 8. As soon as the circuit is broken the armature d rises and
locks the lever j, so that the locking mechanism 4 cannot be moved until the
electric current is again established. The breaking of the current also causes the
armature s to rise, and the lever wis set free, so that the locking mechanism ŕ can
be moved and the lever p actuated. As long as the lever p is not in the position
shown the contact makers 10 are apart, and the electric circuit cannot be completed.
When the shunting operations are finished the lever p is restored to the position
shown, and the contact makers 10 are brought together; the circuit can then bo
completed by turning the key 1. The restored circuit locks the lever w and frees
the lever j. The indicators 7 and 8 are not essential, but it is convenient to have
them. In any case the magnet and key mechanism of 8 is used. The said
mechanism may be placed in the position of the contact makers 9 so as to be
operated by the lever p instead of by hand.
8
It will be obvious that the construction of the locking appliances may be varied
without departing from my Invention.
Having now described and illustrated the nature of the said Invention, in such
manner that others will be enabled to carry my improvements into effect, I
claim,
First. Interlocking main line signals and shunting or siding points, substantially
as herein set forth.
Second. Apparatus constructed to operate and be operated, substantially as
herein set forth,

page_text: Third. Apparatus constructed and combined, substantially as herein set forth
for the purposes specified.
.
In witness whereof, I, the said John William Fletcher, have hereunto set my
hand and seal, this Twenty second day of October, in the year of our Lord
One thousand eight hundred and eighty one.
Witness,
A. S. WORTHINGTON,
93, Chatham St.,
Stockport.
【JNO. W. FLETCHER,,
(L.S.)
☐