Improvements in Railway Signalling Apparatus.
Year: 1894

page_text: Date of Application, 23rd June, 1894-Accepted, 28th July, 1894
Improvements in Railway Signalling Apparatus.
I, WILLIAM SAUNDERS of 34, Park Grove Battersea Park Road, London,
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:-
ก
My invention velates to apparatus for operating railway signals and has for its
object improvements in the apparatus described with reference to my former
Specification for Letters Patent No. 13884 of 1893, in which I provide a pulley
mounted upon the signal-post and formed with a projection or cam for operating
locking-arm and at the same time permitting of the pulley rotating sufficiently to
allow of the full expansion or contraction of the signal wire without unlocking the
said arin, the latter being formed with a notch for receiving the outer end of n
small arm pivoted to the post whereby the signal is locked in its lowest or
"all-right" position.
Now according to my present invention, instead of the aforesaid pulley I mount
loosely upon the signal post a lever of the first order formed of a double frame in
which are mounted three small pulleys around which the operating chain passes,
provided at one end with a weight.
Upon the axis of this lever is fixed a small arm whose outer end enters a notch
formed in a locking-lever, pivoted to the post, when the parts are in their locked
position in a similar manner to that described in my former Specification above
referred to. The locking-lever is also formed with a second notch for locking
the small arm in the "danger" position of the signal. The aforesaid chain-carrying
lever is also provided with a link passing around the small arm and of a length
sufficient to permit of the movement of the said lever, due to the expansion or
contraction of the wire, without operating the small arm and consequently the
signal attached thereto, and bearing against the locking lever so as to disengage
the lower notch from the small arm when putting the signal to "danger." The
locking lever is also provided with a pivoted catch which, when the signal lever is
pulled over to its "safety" position, engages with the aforesaid link so as to
unlock the signal from its "danger" position to permit of its being locked in its
'safety or lower position.
6
"
My invention also consists in means for obtaining extra draught or haulage on
the chain for operating the signal where one pull of the signal-box lever would not
be sufficient to work the signal in consequence of allowing for expansion and
contraction of the wire by means of my improved compensating devices described
in my former Specification of Letters Patent No. 8586 of 1893. For this purpose
the operating pulley, over which the chain passes, is carried in brackets beneath
the quadrant or hand signal lever, and to each side of the pulley is attached a plate
with a portion cut away forming a circumferential path or opening and formed
with two or more similar shaped notches leading from said path. To the outer
side of each of these plates is secured, by means of pins, a curved plate capable
of sliding upon the first-named plates, radial slots formed therein permitting of the
passage of the connecting pins. These outer plates are also each formed with a
radial path or opening similar to and coinciding with that of the inner plates,
and with two or more notches similar to those in the inner plates leading from
the said circumferential path. The lower end of the quadrant lever, at its point
of oscillation, is formed with a horizontal arm or lever, to one end of which are
pivoted two rods the lower ends of which are connected together by a pin passing
through the circumferential paths or openings of the two plates and from whence
it is free to pass into the aforesaid notches whereby the pulley is turned a certain

page_text: distance and the chain thereon operated when the quadrant lever is pulled over,.
the chain being attached to the pulley by means of a bolt and one end being
provided with a weight.
Should one pull over of the quadrant lever not be sufficient to operate the
signal, it is pushed back and pulled over again which operation causes the said
pin to slide out of the first set of notches into the second set, thus causing the
pulley to be turned a further and similar distance to that which it at first travelled.
In order to turn the pulley in a contrary direction the movement of the lever
brings the pin into contact with one end of the outer plates thus causing them
to slide over the inner plates, thereby closing the aforesaid notches and opening
a second series of notches, which notches being formed in a contrary direction
to the first named ones causes the pulley to be turned in a reverse direction
upon pushing the lever over.
In the accompanying sheet of drawings
Fig. 1 is an elevation of an ordinary signal post with my improved apparatus
applied thereto, and Fig. 2 is an elevation at right angles to Fig. 1.
Figs. 3 & 4 are detailed views to a larger scale showing different positions of
my improved apparatus, Fig. 5 being a cross section of the chain carrying lever
and its link.
Fig. 6 is an elevation of my apparatus for obtaining extra draught on the chain,
Fig. 7 being a similar view showing a different position of the parts. Fig. 8 is an
end view thereof, and
Fig. 9 shows a portion of the inner and outer plates attached to the operating
pulley.
Pis an ordinary signal post and A the signal arm. a is the chain carrying lever
formed of two frames a' between which are mounted small pulleys at a³ and a'.
The lever a is mounted loosely on the axis p fixed to the post 1', and over
the pulley a, under the pulley o' and over the pulley a passes the signal
operating chain & whose end is attached to a weight . To the inner frame of
the lever a is fixed a metal loop or link e through which passes au arm d fixed
to the pivoted pin p, the arm d being attached to the rod 'd' for operating the
signal arm in the usual manner. e is the locking lever pivoted to the post Pand
formed with two notches for receiving the end of the arm d and locking the
signal arm in its lowest or highest position respectively. The lever e is also
provided with a catch or projecting piece pivoted thereto so as to be raised by
the link ces the latter is lifted by the motion of the lever a as shown in dotted lines
in Fig. 3, the bottom of the link at the same time bearing against the lever and
disengaging the notch e from the arm d the continued lifting of the link causing
the end of the entch to escape and fall below the top of the link, as shown in
Fig. 4, thus enabling the catch to be acted upon by the link as the latter descends
and causing the levere to be pushed outwards so as to disengage the slot from
the arm d and unlocking the latter and the signal A from its "danger" position.
When the signal box lever is pulled over it draws down the lever a by means of
the chain into the position shown in Fig. 1 the link at the same time bearing
upon the upper edge of the arm d and bringing it and the signal A into their lowest
position, the link c in the meantime acting upon the catches to unlock the arm d
as before described. The latter then enters the notch e whereby it and the signal
are locked in their "safety" position.
The link should be made of sufficient length so as to allow of the oscillating
motion of the lever a due to the expansion or contraction of the signal wires
without affecting the lever e In Figs. 3 and I have shown the lever a curved
instead of straight which enables the chain more easily to clear the pivoted pin p
the said lever being provided with slots a' and holes a for the purpose of adjusting
the positions of the pulleys a², a', and aʻ. By means of my improved apparatus 1
obtain increased leverage and consequently require less weight and power to operate
the signals, at the same time allowing of the full expansion or contraction of the
wires without affecting the working.

page_text: My apparatus for obtaining extra draught or haulage on the chain where one pull
of the signalman's lever is insufficient is illustrated in Figs. 6 to 9 in which
represents the pulley over which the operating chain passes and to which it is
connected by means of a bolt or pin f¹.
and
This pulley is supported in brackets g underneath the hand lever quadrant
upon each side thereof is fixed a plate i having a portion cut away forming a
circumferential path leading into two notches A plate & is attached by means
of pins or studs to the outside of each of the plates i, the said plates being
formed with a radial path or opening coinciding with that of the plates i and also
with notches similar to the notches . The hand-lever is provided with a
horizontal arm or lever at its point of oscillation, to one end of which are
pivoted two rods m connected together at their lower ends by a pin m'. Fig. 6.
represents the lever as having been pulled over to lower the signal but should this
not be sufficient to operate the signal in consequence of allowing for the expansion
and contraction of the wire by means of my improved compensation devices, the
lever is pushed back thus causing the pin m to slide out of the notches up the
inclined portions (Fig. 9) into the path i¹ from whence the pin enters the second
set of notches so that upon the lever being again pulled over it draws the
pulley ƒ round in the direction of the arrow (Fig. 6) the same distance as before.
In order to rotate the pulley in a contrary direction the lever is pushed
back a short distance thus causing the pin m' to engage with the curved ends
the plates and sliding the latter along the plates thereby disclosing the
notches, and closing the notches to the radial path. Upon pushing over
the lever the pin m' enters the first set of notches and the pulley is rotated in
the direction of the arrow (Fig. 7). The plates k are formed with slots through
which the studs pass for permitting of their sliding motion and they are also
formed with a slot (Fig. 9), through which passes the end of a flat spring n
attached to each plate and bearing upon the plates i for preventing the shifting
of the plates & except when operated upon. By means of this apparatus the pulley
is free to allow of expansion and contraction of the signal-wire, to a certain extent,
and by reason of the lever not being rigidly connected to the said pulley there is
less strain on the wire after the lever has been pulled over.
of
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 combination of the compensating lever a
provided with pulleys a, a and a, the link c, arm d, and locking lever e,
substantially as described and for the purposes specified.
2. In railway signalling apparatus the pivoted locking levere formed with
notches e and e² and provided with a pivoted catch e substantially as described
and for the purposes specified.
3. In railway signalling apparatus the combination of the operating pulley f, the
plates and formed with circumferential paths and notches and and
connected together by studs k¹ entering slots k³, slots &ª and springs n substantially
as and for the purposes specified.
4. In combination with the preceding claim, the quadrant-lever, lever l', rods m
and pin m³ substantially as described and for the purposes specified.
5. The improved railway signalling apparatus substantially as described and
shown in Figs. 1 to 5 and 6 to 9 respectively of the accompanying drawings.
Lנים
£1904
F. G. CASSELL,
Of Cassell & Co.,
22, Glasshouse Street, Regent Street, London, W.,
Agent for the Applicant.