Improvements in Railway Signalling Apparatus.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Railway Signalling Apparatus.
I, ELI WILLIAM PERRETT, of 23, Llantwit Street, Cathays, Cardiff, Railway
Signal Superintendent, do hereby declare the nature of this invention to be as
follows:-
This invention relates to railway signalling. It consists in apparatus whereby
a train causes a signal or signals appertaining to the line of rails on which it
runs to be put on, that is, to indicate danger, as such train passes the said signal
or signals. For convenience in description, the invention will be set forth as
applied to a case where there is both a distant signal and a "home" signal.
Opposite, or approximately opposite, the home signal, or as nearly so as may
be convenient, is a treadle arrangement which may vary in construction. Under
one form it consists of a pair of counterweighted levers pivotted to one of the rails
of the track and so arranged that a part of the lever or levers normally projects
above the level of the top of the rail so as to be in position to be acted upon by
one of the leading wheels of a locomotive. On that side of the track at which the
signal connections are situated, is pivotted, in a bracket or other suitable sup-
port, a lever which, on one side of the pivot, carries a counterweight, and the
other a frame in which are carried in bearings two pairs of pulleys for the chains
or wires whereby the signals are operated.
"
When the signals are off," indicating "line clear," the frame carrying the
pulleys is not free to rock, as it is restrained in one direction by a fixed bar
against which it is held by the counterweight carried by the lever, and it is
restrained in the other direction by a diagonal stop fixed on a plate which is
connected to the treadle aforesaid by a rod extending, transversely to the line
of rails. With the apparatus in this position the signals are free to be operated
as ordinarily.
When the treadle is depressed by one of the leading wheels of a locomotive,
the plate above mentioned as having fixed to it a diagonal stop, is moved out-
wards and frees the frame carrying the pulleys. The frame, being outweighed
by the counterweights pivotted on the signal post, is tilted, and thus the strain
is relaxed on the chains or wires, and the signals are both put to danger. The
range of movement of the frame is limited by a further stop to which it swings.
The signals having been thus put on to indicate danger by the passing
train, and the treadle depressed, they remain in this state, and the signal-man
is unable to pull the signals off to give "line clear" until the hand levers have
been so actuated as to restore the pulley-carrying frame and the mechanism per-
taining to the apparatus to the position occupied before the advent of the passed
train. Until this is done the signals remain unaffected by actuation of the hand
levers.
The apparatus, which may be placed on either side of the track, is adapted for
use in connection with all classes of lever signals.

page_text: As will be readily understood, when there is but one signal, the swinging frame
carries one pair of pulleys only.
The apparatus is applicable as controlling apparatus at intermediate sidings
and stations where signals are required to be controlled by ground frames at such
sidings and stations when covered by signals from another signal box. In such
cases, the usual additional wires and controlling plates are dispensed with. The
treadle is not required in such cases, as the pulley-carrying swinging frame is
worked by a connection with the ground frame lever.
NICHOLAS WATTS,
Chartered Patent Agent, Bristol.
Improvements in Railway Signalling Apparatus.
I, ELI WILLIAM PERRETT, of 23, Llantwit Street, Cathays, Cardiff, Railway
Signal Superintendent, 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:-
This invention relates to railway signalling. It consists in apparatus whereby
a train causes a signal or signals appertaining to the line of rails on which it
runs to be put on behind it, that is, to indicate danger and thus block the line in
rear of the said signal or signals. For convenience in description, the invention
will be set forth as applied to a case where there is both a distant signal and a
home signal.
Opposite, or approximately opposite, the home signal, or as nearly so as may
be convenient, or otherwise suitably situated, is a treadle arrangement which
may vary in construction. Under one form it consists of a pair of counter-
weighted arms pivotted to one of the rails of the track and so arranged that a part
of one arm, or both of them, normally projects above the level of the top of the
rail, so as to be in position to be acted upon by one of the leading wheels of a
locomotive. On that side of the track at which the signal connections are
situated, is pivotted, in a bracket or other suitable support, a lever which, on one
side of the pivot, carries a counterweight, and on the other side of the pivot a
frame in which are supported in bearings two pairs of pulleys for the running
chains or wires whereby the signals are operated.
<
When the signals are off," indicating "line clear," the frame carrying the
pulleys is not free to move, as it is restrained in one direction by a fixed bar
against which it is held by the counterweight carried by the lever, and it is
restrained in the other direction by a diagonal stop fixed on a plate which is
connected to the treadle arrangement aforesaid by a rod extending transversely
to the line of rails. With the apparatus in this position, the signals are free to
be operated as ordinarily.
When the treadle is operated by one of the leading wheels of a locomotive,
the plate above mentioned as having fixed to it a diagonal stop, is moved out-
wards and frees the frame carrying the pulleys. The frame, being outweighed by
the usual counterweights pivotted on the signal post, is tilted, and thus the strain
is relaxed on the chains or wires, and the signals are both put to danger. The
range of movement of the frame is limited by another stop to which it may swing.
The signals, having been thus put on to indicate danger, by the passing train,
they remain in this position and the signalman is unable to pull the signals off
to give "line clear" until the hand levers by which the signals are operated have

page_text: the hand levers.
been so actuated as to restore the pulley-carrying frame and the mechanism per-
taining to the apparatus to the position occupied before the advent of the now
passed train.
Until this is done, the signals remain unaffected by actuation of
Referring to the accompanying drawings, Fig. 1 represents in side elevation
a part of my improved railway signalling apparatus applied to a case where
there is both a distant signal and a home signal. Only the home signal is shown in
the drawing. The distant signal is similar to the home signal, and each is fitted in
the usual way with a counterweight and a semaphore arm and connections
arranged as ordinarily. At Fig. 1 of the drawings the rail and treadle are, for
the purpose of avoiding complication, not shown. Fig. 2 is a view of the left-
hand end of Fig. 1. Fig. 3 is a plan, but without either signal. Only one rail
is shown, namely, that to which the treadle mechanism is applied. The other
rail of the track is, as is obvious, understood to be on the other side of the gauge.
For the sake of greater clearness, the signal chains and wires A and B (shown in
Figs. 1. 2 and 3) are diagrammatically indicated by lines of dots and dashes
except, in certain places, where they would, in practice, be hidden from view.
In such certain places they are indicated by dotted lines. Fig. 4 is an elevation
of the treadle mechanism as seen from between the rail and the signal-controlling
apparatus.
On that side of the track at which the signal connections are situated is fixed
a frame such as a which may be conveniently secured by being bolted to sleepers
extended outwards from the rails. The frame a is situated at any suitable and
convenient point between the home signal and a signal cabin or place of opera-
tion of the hand levers by which the signals are put on and off. Adapted to
swing on the spindle 6 is a lever c to which is rigidly secured a cradle & which
carries two pairs of pulleys e and f free to turn on spindles el and f¹. The
lever c carries a counterweight c¹ which is adjustable, and is secured at the place
of adjustment by the binding screw c². The counterweight c¹ tends always to
keep the lever c and cradle d in the position shown at Figs. 1, 2 and 3 of the
drawings. In this position of the cradle the signals are free to be operated in
the usual way from the signal cabin or other place of actuation; the chains A
and B running on the pulleys, and the cradle d remaining stationary and un-
affected. The counterweight c¹ keeps the front of the toe d of the cradle in
contact with the stop 9 extending across the frame a. Behind the toe d' is a
fixed diagonal stop bar carried upon a plate connected by a rod i to a bell-
crank lever connected by links j to a pair of arms k pivotted, as at k², to the
web of the rail and having counterweights at their outer ends. The arms k are
linked together loosely at . At Fig. 5 is shown a detached plan of the plate h,
and at Fig. 6 is shown a side view, partly sectional, of the connection together
of the rod i, bell-crank i¹, links j and arms k. The counterweights keep, in the
absence of a counteracting force, the inner ends of the arms kabove the level of
the rail top.
position of the
The wires and
are tilted back,
The signals having been set to indicate "line clear," the
mechanism and connections is as shown at Figs. 1, 2 and 3.
chains A and B are tight and the semaphore arms of the signals
as is usual. A part of a semaphore arm m appertaining to the home signal is
seen at Fig. 1.
When the leading wheel of the locomotive of a passing train runs over the
arms k, the inner ends of the arms become depressed, the counterweights / be-
come tilted up on the pivots and, through the connections i, and j, the
plate his moved outwards, and, the toe d¹ of the cradle d being thus freed from
contact with the end of the diagonal stop bar h', the cradle d swings to the
position shown at Fig. 7, thus giving a certain length of slack chain to both the
home and distant signals which move, accordingly, to "danger" simultaneously,
or approximately so, under the influence of their own counterweights, which pre-
ponderate over the counterweight on the lever c.
The train, in passing,

page_text: 65
In order to restore the cradle to the normal position, the hand-lever by which
the distant signal is operated is first returned or, as it is technically expressed,
put back." This produces slackness of the chain or wire B between the hand
lever and the distant signal. The cradle is still held by the chain of the home
signal in the position shown at Fig. 7. The hand-lever of the home signal is
next put back," and both chains or wires A and B having been in turn thus
made slack between the hand-levers and the signals, the cradle d, no longer
restrained, is returned by its own counterweight c¹ to the position shown, at
Figs. 1, 2 and 3. As the cradle d moves to this position, the counterweights
of the arms & cause the plate h to be drawn towards the rail, and the inner ends
of the arms are raised above the level of the rail top to their normal position
—as seen at Figs. 4 and 6-ready for re-actuation by a wheel of the locomotive of
the next train.
An antifriction roller d is fitted in the cradle, as seen at Fig. 2. It assists to
keep the cradle in position laterally.
Instead of the frame a for carrying the cradle d, other kinds of supports may
be employed, such as a suitable bracket or post. The treadle mechanism may
also vary, it sufficing that it shall be such as to impart a reciprocatory movement
to the plate h as above set forth.
In cases where there is but one signal, the swinging frame carries one pair
of pulleys only.
The apparatus is applicable as signal-controlling apparatus at intermediate
sidings and stations where signals are required to be controlled by ground frames
at such sidings and stations when covered by signals from another signal box.
In such case, the usual additional wires and controlling plates are dispensed with.
The treadle arrangement is not required in such cases, as the pulley-carrying
swinging frame is worked by a connection with the ground frame lever, as shown
at Fig. 8 which illustrates such a case. The rod n is connected to the ground
frame hand-lever and to the toe d' of the cradle d. In lieu of the rod ja wire
or chain may be employed, but where a wire or chain is substituted for the rod
such wire or chain can be fixed from one direction only, whereas a rod can be
fixed from either direction to work direct.
Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. Railway-signal controlling apparatus, consisting of a counterweighted
cradle such as d, pivotally supported in a frame such as a, or in or on other suit-
able support, and carrying pulleys such as e and f over or about which are con-
ducted the wires or chains connecting the signal-operating levers to the signals;
the said cradle being connected by a treadle arrangement so disposed and arranged
with respect to one of the rails of a railway as to be acted upon by a passing
train in such manner as, through the medium of the cradle aforesaid, to put the
signals "on," that is, to danger, substantially as hereinabove described with
reference to the accompanying drawings.
2. In railway-signal controlling apparatus as set forth in the preceding claim,
mechanism for actuating the cradle d, such mechanism consisting of counter-
weighted arms such as , pivotally connected to the web of the rail of the railway
and loosely coupled or hinged at their inner ends, and so set and disposed
as to normally have their inner ends sufficiently elevated as to be acted upon by
a wheel of a passing train so as to cause the said cradle d to be moved to put on
the signals, substantially as described with reference to the accompanying
drawings.

page_text: 3. The plate with diagonal stop-bar h¹ connected to the treadle mechanism
and so arranged as to restrain the cradle from being swung by the counter-
weight cl when the arms of the treadle mechanism are in their normal position,
that is to say, with their inner ends elevated, substantially as hereinabove
described with reference to the accompanying drawings.
4. Means for connecting the plate h to the treadle arms, said means consisting
of a rod such as i, bell-crank lever and links such as j, arranged and operating
as described.
5. The modification hereinabove described with reference to Fig. 8 of the
drawings, that is to say, in which the cradle d is operated through a rod such
as n, or its equivalent. connected to a ground frame hand-lever and to the cradle.
Dated this 9th day of February 1899.
NICHOLAS WATTS,
Chartered Patent Agent, Bristol.