Improvements in Railway Signalling Apparatus.
Year: 1891

page_text: Date of Application, 22nd Apr., 1891
Complete Specification Left, 21st Jan., 1892-Accepted, 9th Apr., 1892
PROVISIONAL SPECIFICATION.
Improvements in Railway Signalling Apparatus.
I, SAMUEL TELFORD DUTTON of Marl Bank in the City and County of
Worcester, Civil Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention has reference to improvements in interlocking apparatus and in the
interlocking of points and signals upon railways, for the purpose of reducing
the liability of accidents through signalmen forgetting that trains are in their
sections and so lower their stop or other signals allowing trains from the sections
in the rear to approach and thereby causing collisions.
At the present time a signalman after having lowered his stop signal at any
section and the train got within the home signal, can either leave the train
between the home and the starting signal, forget it and take on another train
from the section in the rear, lower the stop signal a second time and create an
accident, or what is more usual he may lower his stop signal a first time, shunt
through a cross-over road to, say the up line, there forget it, possibly performing
an intervening movement on the down line which takes his attention for the
time, and if a train is suddenly rung on to him from the rear on the up line
he may thoughtlessly lower his up stop signal and allow a collision to take
place with the shunted train which is on the up line thus causing an accident
similar to that which occurred at Taunton on the Great Western Railway on
Nov. 11th 1890.
With my invention I arrange incidental levers between the working levers of
the interlocking apparatus, one which I will call a referring to the up side and
another which I will call d referring to the down side.
These levers when pulled over work nearer to the floor than the ordinary
levers and when in their worked position are at an angle to show a label which
is fixed on the back side of the lever with any superscription such as "train on
line,"
""line blocked" or "train waiting."
frame.
Instead of allocating ordinary levers for the purpose of working the disc
Signals appertaining to the cross-over road, that is to say a disc working from
the down to the up line and another from the up to the down, I arrange
incidental levers similar in construction to those previously referred to but which
are for working the disc signals. The one referring to a shunt back movement
from the down to the up line I will call band from the up to the down c.
Usually a cross-over road is normally free when all the levers are back in the
With my invention I arrange that the cross-over road lever say 5,
operating the cross-over road, is normally locked and can only be unlocked by
the movement of both the incidental levers a and d. Suppose a movement now
to take place from the down to the up, before the cross-over road lever 5 can
be operated to allow the crossing to be moved the two incidental interlocking
levers a and d have to be moved over thereby blocking the up and the down
lines by locking the stop signals at danger on the respective lines. Suppose now
that the train should stop in that position and not shunt through the cross-
over road, although the crossing may be replaced yet the fact of pulling over
levers a and d although they may be replaced again does not release the stop
signals for even then they cannot be lowered until the proper movement has
been gone through of working over the incidental lever band working the disc
for the shunt movement from the down to the up line or as the case may be
the incidental lever c working the disc signal from the up to the down. The

page_text: discs cannot be worked until the points are right for the movement and conse-
quently the crossing has to be worked over and the disc lowered and put to
danger again before the stop signals can be operated.
In order however that even when the train has performed a movement and, say
got on to the up line, and things are placed normal again, yet to prevent it being
forgotten, the up stop signal cannot be lowered even then until the starting
signal has been given for the train to depart, or failing that if a shunting movement
has simply taken place for the purpose of clearing the down line, then the shunt
back disc worked by the incidental lever c must be given to shunt the train back
again, when the said train even now arrives on the down line the stop signal for the
down line is not free until the starting signal has been given and replaced.
It is obvious that where extended points are concerned, that is to say where a
siding is provided either on the up or down line, the same arrangement takes place
with reference to the incidental levers, practically one to each pair of points leading
off the main line, and until such incidental lever has been replaced to danger and
the proper disc given so that the movement is clear of the main line and not till
then can the fouling stop signal be given.
My invention is therefore capable of enlargement to any series of sidings or
crossings in connection with stations or other block sections, the benefit derived
being that the train or vehicles must be shunted clear of either line before the stop
signal for the road fouled can be given after once the safety of the line has been
suspended by the movement of conflicting points.
Although in the hereinbefore described invention I have referred to incidental
levers as being separately provided for the purposes of the said invention yet it is
obvious that ordinary levers may be used for this purpose, their action and object
being identical with that of the previously referred to incidental levers.
JOHN P. O'DONNELL,
2, Great George Street, Westminster, London, S.W.,
Agent for the said Applicant.
COMPLETE SPECIFICATION.
Improvements in Railway Signalling Apparatus.
I, SAMUEL TELFORD. DUTTON of Marl Bank in the City and County of
Worcester, Civil Engineer, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement :-
My invention has reference to improvements in interlocking apparatus and in the
interlocking of points and signals upon railways, for the purpose of reducing the
liability of accidents through signalmen forgetting that trains are in their sections
and so lower their stop or other signals allowing trains from the sections in the rear
to approach and thereby causing collisions.
At the present time a signalman after having lowered his stop signal at any
section and when the train has arrived under the protection of the home signal, can
either leave the train between the home and the starting signal, forget it and take
on another train from the section in the rear, lower the stop signal a second time
and create an accident, or what is more usual he may lower his stop signal a first
time, shunt through a cross-over road to, say the up line, there forget it, possibly
performing an intervening movement on the down line which takes his attention for
the time, and if a train is suddenly rung on to him from the rear on the up line he
may thoughtlessly lower his up stop signal and allow a collision to take place with
the shunted train which is on the up line thus causing an accident similar to that
which occurred at Taunton on the Great Western Railway on November 11th
1890.
With my invention I arrange incidental levers between the working levers of the

page_text: interlocking apparatus, one which I will call a (Figure 2) referring to the up side
and another which I will call d referring to the down side.
These levers when pulled over work nearer to the floor than the ordinary levers
and when in their worked position are at an angle to show a label which is fixed on
the back side of the lever with any superscription such as "train on line," "line
blocked," or "train waiting."
Instead of allocating ordinary levers for the purpose of working the disc signals
appertaining to the cross-over road, that is to say a disc working from the down to
the up line and another from the up to the down, I arrange incidental levers similar
in construction to those previously referred to but which are for working the disc
signals. The one referring to a shunt back movement from the down to the up
line will call band from the up to the down c. Usually a cross-over road is
normally free when all the levers are back in the frame. With my invention I
arrange that the cross-over road lever say 5, operating the cross-over road, is
normally locked and can only be unlocked by the movement of both the incidental
levers a and d.
Suppose a movement now to take place from the down to the up (Figure 1)
before the cross-over road lever 5 can be operated to allow the crossing to be moved
the two incidental interlocking levers a and d have to be moved over thereby
blocking the up and the down lines by locking the stop signals at danger
on the respective lines. Suppose now that the train should stop in that
position and not shunt through the cross-over road, although the crossing may
be replaced yet the fact of pulling over levers a and d although they may be
replaced again does not release the stop signals for even then they cannot be
lowered until the proper movement has been gone through of working over the
incidental lever band working the disc for the shunt movement from the down to
the up line or as the case may be the incidental lever c working the disc signal from
the up to the down. The discs cannot be worked until the points are right for the
movement and consequently the crossing has to be worked over and the disc
lowered and put to danger again before the stop signals can be operated.
In order however that even when the train has performed a movement and, say
got on to the up line, and things are placed normal again, yet to prevent it being
forgotten, the up stop signal cannot be lowered even then until the starting signal
has been given for the train to depart, or failing that if a shunting movement has
simply taken place for the purpose of clearing the down line, then the shunt back
disc worked by the incidental lever c must be given to shunt the train back again,
when the said train even now arrives on the down line the stop signal for the down
line is not free until the starting signal has been given and replaced.
C
It is obvious that where extended points are concerned, that is to say where
siding is provided either on the up or down line, the same arrangement takes place
with reference to the incidental levers, practically one to each pair of points leading
off the main line, and until such incidental lever has been replaced to danger and the
proper disc given so that the movement is clear of the main line and not till then
can the fouling stop signal be given.
My invention is therefore capable of enlargement to any series of sidings or
crossings in connection with stations or other block sections, the benefit derived
being that the train or vehicles must be shunted clear of either line before the stop
signal for the road fouled can be lowered after once the safety of the line has been
suspended by the movement of conflicting points.
Although in the hereinbefore described invention I have referred to incidental
levers as being separately provided for the purposes of the said invention yet it is
obvious that ordinary levers may be used for this purpose, their action and object
being identical with that of the previously referred to incidental levers.
In order that my said invention may be better understood and more readily
carried into effect I will describe the drawings hereunto annexed, in which the same
letters refer to the same parts or substitutes therefor in the several figures.
Figure 1 is a plan of an ordinary station with a cross-over road. In this firrure

page_text: the numbers refer to the levers in the locking apparatus set apart to operate the
signals and points to which they refer.
1 is the up distant signal, 2 the up stop signal, 3 the up starting signal, 4 the up
advance starting signal, and 5 is the cross-over road.
bis the incidental lever operating the disc signal for a shunting movement
through the cross-over road 5 from the down main to the up main; e is the incidental
lever operating the disc signal for a shunting movement from the up main through
the cross-over to the down main; d although marked does not operate anything on
the ground but is the incidental lever controlling the operations and providing the
necessary safety locking when it is moved, for movements from the down main to
the up; a in a corresponding and similar manner is the incidental interlocking lever,
hot operating anything on the ground, but provided for protection for shunting
movements from the up main to the down.
6 is a pair of siding points, 7 is the down main starting signal, 8 the down main
home signal and 9 the down main distant signal.
Figure 2 is a side elevation of an interlocking apparatus showing the incidental
lever bin its normal position.
The incidental levers a and d and levers corresponding in their nature and results
to these levers, would be provided with a label f. In the normal position the
superscription on the label could not be read, but when the lever is in its worked
position as shown in the dotted lines the superscription on the label f, such as
"train on line," "line blocked," or "train waiting," could be read.
The incidental lever is provided intermediate between the main levers and is
fixed upon a bracket y attached to the segment plate of the locking frame; & is
the fulcrum of the said incidental lever.
As hereinbefore mentioned the design of the incidental levers b and c operating
the discs referred to in Figure 1, are similar in construction and shape to the
incidental levers a and d as shown in this figure. To the levers b and c a tail ? is
provided as in Figure 2, to which a shackle is attached and the wire run to the
disc it is intended to work.
To provide for the interlocking of these levers a connecting link n of the incidental
locking lever (which for locking purposes has to be provided with a tail) is provided
and attached to a locking tappet m which acts through the usual locking trough and
interlocks in connection with other levers in a similar manner to the main levers
interlocking with each other. o is the locking trough through which the tappet m
operates; p is the main lever.
The incidental levers are held over or held normal in the usual manner by means
of a catch handle and spring catch.
Figure 3 is a front view showing the main levers and the incidental levers and
the connections for interlocking purposes.
Figure 4 is a front view of the block instrument showing the badge in lieu of the
stop piece. This badge obstructs from view the handle of the instrument.
Figure 5 illustrates a front view of two main levers with an intermediate incidental
lever. The handle of the incidental lever is made in the form of a loop for the
protection, if desirable, of the signalman's hand in the event of the main levers
being close together. A balance weight is fixed to this lever to keep it in either
position.
"
Referring to Figure 2, I sometimes connect an upright rod from the tail of
the incidental lever b, so that when the said incidental lever is operated an
upward movement is given to the rod », and at the termination of the rod is a
badge or other means by which upon the completion of the upward movement
the handle of the block instrument is obscured from view or prevented from
being worked the said badge or stop piece coming in front of the said handle
or plunger. This would prevent a signalman from operating his instrument,
unless, in the case of the badge, he took unnecessary pains by putting his hand
at the back.

page_text: On the said badge any similar superscription can be put, as "train waiting,"
"train on line," "line blocked."
is the block instrument and the plunger; is the badge or stop piece
referred to.
The operation briefly consists that when the cross-over road is required to be
operated, according as to whether the train is on the down or up line and it is
required to be shunted from the down to the up or the up to the down, so
either a or d incidental lever is operated. When the operation of either one of
these takes place the connecting link n is moved, the tappet m is in consequence
also moved, and the necessary interlocking is effected by the ordinary means, in
the locking trough o. This releases the respective disc and the cross-over road
lever, and although the crossing may be replaced and the disc replaced also,
still the conflicting train from either direction on either the up or the down
line, could not be allowed beyond the stop signals until the incidental inter-
locking lever had been replaced to its normal position. As previously described
the starting signals must be lowered to allow it to pass out of the section
before the stop signal can be. lowered.
Although I have hereinbefore described my special levers as incidental levers
fixed intermediate between the main levers, yet I may utilize main levers for that
purpose, and in that case the interlocking would be performed in the ordinary way.
It is also obvious that the special attachment of the connecting link to the
tappet m, might be arranged to suit any of the well known interlocking apparati
which use tappet locking.
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 :-
1. In railway signalling apparatus, the provision of interlocking levers (as
distinct from working levers) that release cross-over road or siding points,
operating substantially in the manner and for the purposes herein set forth.
2. In railway signalling apparatus the arrangement of incidental levers placed
intermediate between the main levers for the purpose, on the one hand of
specially interlocking the cross-over road, and on the other hand for the operating
of disc signals, substantially in the manner set forth and as illustrated in the
accompanying drawings.
3. In railway signalling, the combination of apparatus as shown on the accom-
panying drawings, substantially as described and for the purposes specified.
Dated this 21st day of January 1892.
JOHN P. O'DONNELL,
2, Great George Street, Westminster, London, S.W.,
Agent for the said Applicant.