Improvements in Railway Signalling Apparatus.
Year: 1891

page_text: Date of Application, 11th Nov.. 1891
Complete Specification Left, 15th Feb., 1892-Accepted, 16th Apr., 1892
PROVISIONAL SPECIFICATION.
Improvements in Railway Signalling Apparatus.
I, WILLIAM GEORGE SCOTT of the Central Station, Ranelagh Street, Liverpool,
in the County of Lancaster, Engineer, do hereby declare the nature of this inven-
tion to be as follows:-
This invention has for its object the prevention of accidents in such cases as the
late one near Norton Fitzwarren Junction, Taunton, where a train was shunted
from the down line onto the up line to allow an express to pass along the down line,
and then the up line was signalled clear, the signal-man forgetting that he had
left an obstruction on the said line.
I carry out my invention without in any way adding to the signal-man's duties,
the apparatus working exactly as before so long as the signal-man does his duty,
but if, through any chance, he commits a similar mistake to that of the Taunton
signal-man, he is instantly reminded of it by his apparatus becoming unworkable
until he removes the obstruction, or pulls the lever entirely over on purpose to
remedy the defect. In order to illustrate it we will take an actual example, a box
of 12 levers. Of these levers--
No. 2 is the down home signal;
No. 3 the down starting signal;
No. 4 the cross over road signal up to down line;
No. 6 the cross over points.
No. 9 the cross over road signal, down to up line;
No. 10 the up starting signal, and
No. 11 the up home signal.
The other levers are for purposes which do not refer to the invention in question,
and therefore it is needless to describe them.
I employ a case for the lock connecting rods similar to those ordinarily in use.
In the grooves of this case, the connecting rods slide.
In the signal box I am describing, the tappets of Nos. 2 and 11 are parallel ones
with square notches for the locks. The tappets of Nos. 3, 4, 9 and 10 are very long
tapering wedges requiring a lever to be entirely pulled over before they move their
square end locks sufficiently to unlock levers 2 or 11 respectively. The lever 6 has
two triangular notches having equal slopes on both sides corresponding to the nosed
locks also equally sloped on each side. The connecting rod in one groove of the
case has square sided locks on one side of tappets 2, 3 and 9, and a pointed or double
sloped nosed lock on the other side of tappet 6. In a similar way, the other con-
necting rod has square nosed locks on one side of tappets 4, 10 and 11, and a double
slope nosed lock on the other side of tappet 6, the two locks of tappet 6 being on
opposite sides of the tappet fitting their respective notches. Tappet 6 is also
provided with a peculiar cam arrangement, whereby, after the tappet has been
pushed over so far as to push back the nosed cams, it shall rise up above the level
of the pointed nose, but not above the higher squared body of the lock, whereby
the lock can be brought into the position to be operated on by the tappet even
before the lever 6 has been pulled back into normal position.
The mode of action I will illustrate by a definite case;
A train is to be shunted from the up line on to the down line in order to allow
an express to pass on the up line, the signal-man pulls over cross over road points 6,
this at once presses back the noses of both its locks, and by this means presses the
square nosed locks into the square notches of the home signals 2 and 11, and also
places the two locks against the starting signals 3 and 10 and the two locks against

page_text: the cross over road signals 4 and 9. He now pulls the signal 4, and shunts the
engine or train on to the down line. Pulling the signal 4 however brings over its
connecting rod, and releases the home signal 11, thus signalling the up line clear.
The down line however is still locked. If now the signal-man attempts to signal
the down line as clear, he cannot do it as the signal 2 is locked, and he can only
release signal 2 by either specially working the down starting signal 3, or shunting
back the train by means of the lever 9. Either of these, if pulled fully over,
releases home signal 2, and in practice one of these would in any case be pulled
over in the ordinary safe working of the line. Points 6, when brought back
into position, are ready again to lock both lines when the signal-man signals for a
train to cross over. Besides the system of arranging the locks, (so that the mere
use of the cross over points shall lock both lines, and shall continue to lock one line
after the train has been brought back, or the starting signal has been moved
to indicate that the line is clear) there are several other points which I at present
believe to be novel in this invention, among which I would mention the square nosed
locks and square nosed notches for the purposes described, the double sloped nosed
locks with a raised square body, and the arrangement of cams or their equivalent
mechanism, whereby, when the cross over points have moved sufficiently far to press
back the pointed noses to the locking position they shall rise up so high as to allow
the nose to pass beneath them, but not sufficiently to free the body of the lock, and
lastly the tapered tappets so arranged that it is only by drawing the lever fully
over that the unlocking can be effected, and thus a signal cannot be unlocked by a
mere slight movement of the lever insufficient to work its own legitimate duty, but
only by the full working of that lever doing its proper duty.
Dated this 10th day of November 1891.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Railway Signalling Apparatus.
I, WILLIAM GEORGE SCOTT of the Central Station, Ranelagh Street, Liver-
pool, in the County of Lancaster, 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 :-
My invention for improvements in lock signalling consists of additions to the
interlocking of levers working points and signals ordinarily in use on railways.
These additions to the interlocking, which I have named automatic check
locking, are for the purpose of preventing a signalman forgetting that he has
shunted a train from one main line to another (as was the case, and which caused
the accident at Norton Fitzwarren near Taunton on the 11th November, 1890) or
from a goods line or siding to a main line.
My invention attains something more than this; for providing that, after a
train has arrived inside a home signal, a cross-over-road from the main line upon
which the train is standing to another main line, or to a goods line or siding be
used; the train will be protected by the fixed signals until it is allowed to
depart into the section in advance, or until it has been shunted clear of the main
lines.
That my invention may be understood, I proceed to describe the drawings here-
unto attached, such description enabling anyone to carry out the same principle
in all cases differing from that illustrated, such as at junctions, places where
there are more than two main lines, or where there are goods lines or sidings,
or both.
Figure 1 is a diagram of an ordinary block signalling station where there is a
cross-over-road from one main line to the other.

page_text: 5 spare.
"
"
"
"
6 cross-over-road points.
"
"
"
"
دو
"
"
32
"
""
7 facing-point-lock on No. 6 points.
8 spare.
9 down to up line signal.
10
up starting signal.
11 up home signal.
12 up distant signal.
My invention only affects levers 2, 3, 4, 6, 9, 10 and 11, and it must be under-
stood that the usual interlocking between these levers, namely, 2 and 11 inter-
locking with 6, 3 and 10 locking and back locking 6, 6 preceding 4 and 9, and 4
and 9 interlocking, is to be carried out by any of the ordinary systems at present
in use.
Figure 2 is a plan, and Figure 3 a section, of an ordinary locking case (the plan
shown with the cover removed) for locking gear well known as "tappet" locking,
and the parts numbered according to the levers to which they are attached 2, 3,
4, 6, 9, 10 and 11 are tappets; 2, 6 and 11 being similar to tappets ordinarily in
use but having pieces a a¹ a² on their under sides, being an elevation of these
pieces. Tappets 3 and 10 are tapered and have pieces c, c', on their under sides;
d being
an elevation of these pieces; and tappets 4 and 9 are tapered only-
e and are locks known as tee-locks and are similar to those ordinarily in use,
excepting that the nose part is thinner than the body of the lock as shown in the
section, Figure 5.
The object of the inclined blocks a a¹ and a², fixed to the tappets, is to provide
fulcrums or turning points for these tappets, when the tappets 2, 6 or 11 have been
sufficiently moved, their respective inclined blocks will come to rest on the
frame, so that the tappets will then be able to rise on the blocks and allow the
respective locks abutting on the tappets to slide under such tappets. Further,
the object of the blocks c and c' on tappets 3 and 10 is, when the levers of these
tappets have been sufficiently drawn over, to engage the sloping faces of the
blocks and push these blocks (1) back again. The tappets may be tapered
as usual and as shown in the drawings, so that, when they have been moved
sufficiently far, they will jam in the openings of the frame, thereby controlling the
amount of their movement.
These tee-locks fit into notches cut in the sides of tappet 6. Some of the locks
are thick and some thin, for purposes hereinafter described; f and fare thick,
and 2 and 3 indifferently thick or thin square locks connected together by a thin
understrip of metal in the ordinary way; and 92 and g³ are thick, and g and gl
indifferently thick or thin square locks connected together by a thin overstrip of
metal in the ordinary way, Figure 6. In the drawings, the tappets are shown in the
normal position, with the levers back in the frame, and it is evident that, when
the cross-over-road lever 6 is pulled over, the tappet of the same number will cause
the tee-locks e and e¹ to spread, and these, in their turn, will force the locks,, f
and f3 to the left, and the locks g, g', y² and g³ to the right. This will lock
levers 2 and 11 working the home signals, and these can only be released: 2 by
the pulling over of lever 3 or 9, which will draw the lock out of the notch in
tappet 2; and 11 by the pulling over of lever 4 or 10 which will draw the lock 93
out of the notch in tappet 11, it being possible to do this while the cross-over-
road lever 6 is still over as the piece a¹ on the underside of tappet 6 has, at the
end of the stroke of that tappet, caused it to be lifted sufficiently to allow the thin

page_text: part of the tee-locks e and e¹ to slide under the tappet, the thicker part of the
locks preventing their being pushed too far so that they would not re-engage with
tappet 6 when lever 6, to which the tappet is attached, is put back into its normal
position.
Taking a case in illustration :—
Supposing a train to have arrived inside the home signal 2, which signal has
afterwards been put to "danger," and the train shunted from the down to the up
line, the signal 9 having been used for this purpose; the signalman would now be
free to use signal 2 again, but not signal 11 until signal 4 had been used to signal
the train back to the down line, or signal 10 to allow it to depart on the up line.
Providing that a signalman is in the habit, after receiving and giving the telegraphic
signals for a train, of lowering the home signal before the starting signal, the
above described "automatic check locking" fulfils what is required of it, but I
find, from observation, that many signalmen are in the habit of lowering the
starting signal first, and, to compel the signalman to acquire the habit of lowering
the home signal before the starting signal, and to make him lower the home signal
first, excepting when a cross-over-road between the main lines, or between the
main line and a goods line or a siding, has been used, I shorten the tappets 3
and 10, as shown, and rivet pieces, which I call fast-locks, on to the locking
case at the end of the tappets, or I cut square notches in the tappets 3 and 10 and
rivet pieces on to the locking case as shown in dotted lines, so as to prevent
tappets 3 and 10 being moved by the levers to which they are attached until they
(the tappets) have been lifted above these fast-locks. (In case the square notches
are cut in tappets 3 and 10 and the pieces for the fast-locks rivetted on to the
locking case, as shown in dotted lines, locks f' and g² would have to lie partly by
the side of, and partly on, the pieces rivetted to the locking case.) To lift tappet 3,
I employ the locks i, and i, these being connected together by an understrip of
metal in the ordinary way; lock i is a thin lock, lock indifferently a thick or
thin lock, and lock ¹ a wedge-shaped lock as shown in the section, Figure 4. To
lift tappet 10, I employ the locks k, k', and k², k2 being a thin lock, k indifferently
a thick or thin lock and a wedge-shaped lock as in Figure 4 reversed.
Supposing lever 2 or 6 to be worked, the locks i, i¹ and are drawn or forced to
the left, the wedge-shaped lock raising the tappet 3 over its fast lock.
lever 3 is worked, the piece e on the underside of tappet 3 will come in contact
with the lock and force the locks i, and 2 back into their original positions,
the thin lock i passing under tappet 2 if that tappet is pulled over and lifted by
the piece a on its underside, or the thin part of the tee-lock e will pass under tappet 6
if that tappet is pulled over and lifted by the piece a' on its underside. In like
manner tappet 10 will be released by the working of tappet 6 or 11 and the
locks k, k¹ and k².
When
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. The arrangement of tappet interlocking gear substantially as described,
whereby the using of a cross-over-road point lever automatically locks the signals
on the line (say the "down" line) onto which the train has been shunted until a
signal to shunt the train off that line has been pulled over, or the starting signal
of that line has been pulled over to allow the train to enter the block section in
advance.
2. The arrangement of tappet gear whereby the tappets can automatically rise
up and ride over a lock, substantially as and for the purposes described.
3. The arrangement of locks with one part thick and the other part thin, whereby,
when the tappet is at its normal level, the nose of the lock can come in contact
with it, but, when the tappet is automatically raised, only the higher portion of
the lock shall abut on the tappet.

page_text: 4. The arrangement of long wedge-shaped tappets such as 3, 4, 9 and 10,.
whereby, to obtain any result, the handle must be pulled right over instead of.
being merely jogged.
Dated this 8th day of February 189-
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Nottingham, and London, Patent Agents..