IMPROVEMENTS IN APPARATUS FOR WORKING RAILWAY SIGNALS
Year: 1877

page_text: LETTERS PATENT to William Henry Watson, of 4, Wilton Terrace, Camberwell
Grove, in the County of Surrey, for. the Invention of "IMPROVEMENTS IN
APPARATUS FOR WORKING RAILWAY SIGNALS."
Sealed the 29th January 1878, and dated the 28th August 1877.
PROVISIONAL SPECIFICATION left by the said William Henry Watson at the
Office of the Commissioners of Patents on the 28th August 1877.
WILLIAM HENRY WATSON, of 4, Wilton Terrace, Camberwell Grove, in the
County of Surrey. " IMPROVEMENTS IN APPARATUS FOR WORKING RAILWAY
SIGNALS."
This Invention has for its object improvements in apparatus for working railway
signals.
The distance signals of railways are at present usually worked by means of wires..
Considerable difficulty is found in maintaining the wires at a suitable tension, and
when they become slack the movement of the lever by the signalman does not
produce a corresponding movement of the signal arm.
According to iny Invention I overcome this difficulty, and obtain an automatic
adjustment where the distance is long, by placing midway between the signal box
and the signal an apparatus consisting of a bed or guide, along which a slide
provided with ratchet teeth is able to traverse. This slide is at one end connected
with the wire leading to the signal lever, whilst at the other it has attached to it a
chain passing over a pulley, and having a weight suspended at its free end, so that
the weight keeps the wire from the lever from becoming slack.
Through the end of the bed or guide already mentioned, a draw bar is able to
slide, and it has attached to it the wire leading to the signal post, which serves to
give motion to the signal arm; and also attached to this draw bar there is a chain,
which passes over a pulley and suspends a weight as already described in connection
with the slide, and the weight prevents the wire leading to the signal from becoming
Price 6d 1

page_text: slack. There is also jointed to the draw bar a loop or claw, which takes into the
ratchet teeth of the slide and couples the two parts, so that motion received by the
first from the signal lever is imparted to the second. If the wires should stretch in
use, compensation is effected by the loop or claw passing from one tooth of the ratchet
to another.
Where the distance from the signal box to the signal is not long, I place a similar
apparatus at the foot of the signal post, and in this case I dispense with the weight
in connection with the draw bar, the ordinary counterpoise of the signal arm being
sufficient, where there is not a long length of wire between the signal and the
compensating apparatus.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Henry Watson in the Great Seal Patent Office on the 28th
February 1878.
WILLIAM HENRY WATSON, of 4, Wilton Terrace, Camberwell Grove, in the
County of Surrey. "IMPROVEMENTS IN APPARATUS FOR WORKING RAILWAY
SIGNALS."
This Invention has for its object improvements in apparatus for working railway
signals.
The distance signals of railways are at present usually worked by means of wires.
Considerable difficulty is found in maintaining the wires at a suitable tension, and
when they become slack the movement of the lever by the signalman does not
produce a corresponding movement of the signal arm.
According to my Invention I overcome this difficulty, and obtain an automatic
adjustment where the distance is long, by placing between the signal box and the
signal an apparatus, consisting of a bed or guide, along which a slide provided with
ratchet teeth is able to traverse. This slide is at one end connected with the wire
leading to the signal lever, whilst at the other it has attached to it a chain passing
over a pulley, and having a weight suspended at its free end, so that the weight keeps
the wire from the lever from becoming slack.
Through the end of the bed or guide already mentioned a draw bar is able to slide,
and it has attached to it the wire leading to the signal post, which serves to give
motion to the signal arm; and also attached to this draw bar there is a chain, which
passes over a pulley, and suspends a weight as already described, in connection with
the slide, and the weight prevents the wire leading to the signal from becoming
slack. There is also jointed to or carried by the draw bar a loop or claw which takes
into the ratchet teeth of the slide, and couples the two parts, so that motion
received by the first from the signal lever is imparted to the second. If the wires
should stretch in use, compensation is effected by the loop or claw passing from one
tooth of the ratchet to another.
The Drawings hereunto annexed shew the manner in which I carry out my
Invention.
Figure 1 shews an elevation; Figure 2, a plan view; and Figure 3, a cross section
taken on the line A, A.
In these Figures A. is the signal post; B, the wire passing from the ordinary
weighted lever on this post; C, the bar to which the wire is attached; D, the weight

page_text: and chain for keeping the wire B in tension; E is the bed, through the ends of
which the bar C is free to slide; G is a slide formed with ratchet teeth, which is
also able to slide to and fro along the bed E; H is a wire passing from this slide to
the signal lever; and I, a chain attached to the opposite end of the slide, and after
being passed over a pulley carrying a weight, which serves to draw the slide into
the position shewn in the Drawing, whenever it is free to do so.
The slide G has
pins passed through it which enter slots K, K, in the sides of the bed E. The slots
at one end incline downwards, as shewn, in order that when the slide G is brought
to that end of its to-and-fro traverse, the ratchet teeth on its upper surface shall be
free from the claw L which is carried by the bar C, but when the wire H is drawn
back by the signalman moving the signal lever, the slide G at once rises, and one or
other of the teeth on the slide G engage with the claw L, and cause the bar C
and signal wire connected to it to be drawn back, so as to lower the signal.
When the signal lever is again moved to its original position, the slide G is drawn
back by the weighted chain connected to it, and at the end of its backward move-
ment it descends and frees itself from the claw L. The bed E is secured in as near
a position as conveniently may be to the signal box, in order that the proper action
of the apparatus may not be interefered with by any contraction or expansion of the
wire which connects the signal lever with the slide G; and further, to ensure that the
slide G shall always be drawn back by the weight connected to it to the full extent
of its traverse when the signal is set at danger, the wire between the slide G and
signal lever is then allowed to become slightly slack; any slight contraction of the
wire will thus have no effect upon the proper working of the apparatus, but the
slide G will always be free from the claw L on the bar C when the signal is at
danger.
Instead of the claw L being fixed to the bar C, and the slide G being lifted and
lowered to engage with or disengage itself from the claw, the claw might be jointed
to the bar C, and the slide G simply move to and fro in a straight line; I however
prefer the arrangement shewn, as by that arrangement it is immaterial whether the
wire leading to the signal contracts or expands as it is always set free when the
signal is at danger. Whereas if the claw were always engaging with one or other
of the teeth of the rack there would be no provision for contraction of the wires,
and additional apparatus must then be added to provide for any contraction of the
wire.
Having thus described the nature of my Invention and the manner of performing
the same, I would have it understood that I. claim the combined arrangement of
apparatus, substantially as herein described, for working railway signals.
In witness whereof, I, the said William Henry Watson, have hereunto set
my hand and seal, this Twenty-eighth day of February, in the year of our
Lord One thousand eight hundred and seventy-eight.
TAA