Improvements in Railway Signalling Apparatus.
Year: 1885

page_text: Improvements in Railway Signalling Apparatus.
I, WALTER KING of Houston in the County of Renfrew, Gentleman, do hereby
declare the nature of this invention, to be as follows:-
This invention which relates to Railway Signalling apparatus has for its object
to ensure that the pull, that is to say, the length or lengths of wire, chain or
other connection between the signalman's operating lever and the semaphore or
signal arm, shall be allowed to expand and contract under variations of tempe-
rature without materially affecting the position of the signal arm or permitting it
to vary from its proper position relative to the operating lever.
To effect these objects the semaphore or signal arm is, under this invention,
furnished with a back balance projecting from the opposite side of the fulcrum to
the arm. In conjunction with this balancing portion the usual danger and safety
indicating glasses or "spectacles" are provided, and in addition thereto a second
danger signalling glass is used. In lieu of the usual crank or lever placed on the
fulcrum of the semaphore a pulley is substituted and over this pulley a chain or
band is passed the said chain or 'band being also passed round another pulley
centred on the signal post and having secured to one side of it a lever the ends of
which project beyond the pulley equally from its centre. To prevent slipping the
chain or band is secured at points in the periphery of both pulleys and it con-
stitutes a substitute for the usual rod connection between the signal arm and the
corresponding lever below, the improved arrangement providing a truly balanced
signal arm irrespective of the position in which the said arm is placed.
The signalman's operating lever has a bell crank arm connected by the ordinary
pull to one end of the lever secured to the side of the second before referred to
pulley and another bell crank arm on the said signalman's lever is connected by a
second pull to the other arm of the said pulley lever, the arms of the signalman's
lever and those of the pulley lever being equal in length. The pulls or connecting
wires or chains are strained or stented alike and both are made to pass under
pulleys sustaining one weight at a point, if not equidistant from, then at some
convenient point between the signalman's lever and the semaphore.
With the improved arrangement described the signal arm is maintained at
danger when the signalman's lever is in its normal position and when the said
lever is pulled over the connections between it and the second referred to pulley on

page_text: the signal post cause the said pulley to partially turn round, thereby through the
chain or band passed round it and also round the pulley on the fulcrum of the
signal arm deflecting the said arm to safety. In returning the signalman's lever to
its normal position the signal arm is brought back to danger and maintained there.
In conjunction with the pulley lever a stop plate is provided and in the event of
the additional pull extending between the signalman's lever and the pulley lever
breaking when the signal arm is either at danger or safety the weight of the other
pull and of the weight suspended thereby carries the pulley and lever round until
the semaphore assumes a vertical position at which point further movement is
prevented by the stop plate.
In daylight danger is indicated by the said position of the semaphore and in the
dark. by the position of the extra danger glass or spectacle which by the fall of
the semaphore to the vertical position brought in front of the lamps or light..
In the event of the ordinary pull breaking the weight of the extra pull and of
the suspended weight brings the semaphore to and maintains it at the danger
position.

page_text: COMPLETE SPECIFICATION.
Improvements in Railway Signalling Apparatus.
I, WALTER KING of Houston, in the County of Renfrew, Gentleman, 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:-
This invention which relates to Railway Signalling apparatus has for its object
to ensure that the pull, that is to say, the length or lengths of wire, chain or other
connection between the signalman's operating lever and the semaphore or signal.
arm, shall be allowed to expand and contract under variations of temperature
without materially affecting the position of the signal arm or permitting it to vary
from its proper position relative to the operating lever.
To effect these objects the semaphore or signal arm is, under this invention, and
as shewn by figures 1 and 2, of the accompanying drawings, furnished with a back
balance b projecting from the opposite side of the fulcrum to the arm a.
"
"
In con-
junction with this balancing portion the usual danger and safety indicating glasses
or spectacles c, d, are provided and in addition thereto a further danger
signalling glass e is used. In lieu of the usual crank or lever placed on the fulcrum
of the semaphore a pulley f is substituted and, as seen at figure 1, over this pulley
a chain or band g is passed, the said chain or band being also passed round another
pulley h centred on the signal post i, and having secured to one side of it a lever j
the ends of which project beyond the pulley equally from its centre.
To prevent
slipping the chain or band is secured at points in the periphery of both pulleys f, h,
and it constitutes a substitute for the usual rod connection between the signal arm
and the corresponding lever below, the improved arrangement providing a truly
balanced signal arm irrespective of the position in which the said arm is placed.
The signalman's operating lever k has a bell crank arm / connected by a pull m
to one end of the lever j and another bell crank arm n on the said signalman's
lever is connected by a second puli o to the other arm of the said pulley lever j.
The pulls or connecting wires or chains m, o, are strained or stented alike and both
are made to pass under pulleys p thence over pulleys q, q', and under pulleys r
centred in the upper part of a weight thence over other pulleys q, q¹, and under
pulleys & to the ends of the lever j, the weight being placed at any convenient
point between the signalman's lever and the semaphore.
Figure 3 is a plan and figure 4 an end elevation of the arrangement of the
pulleys q, q' and figure an end elevation of the weight and as shewn by these
figures the pull o at the part where it passes over the pulley q¹ and under the
pulley r, is duplicated the double portion being connected to the main length of the
pull by a shackle t, or the pull m may be so duplicated.
With the improved arrangement described the signal arm a is maintained at
danger when the signalman's lever k is in its normal position and when the said
lever is pulled over the connections between it and the pulley cause the said
pulley to partially turn round, thereby through the chain or band g, passed round
it and also round the pulley f, deflecting the signal arm to safety. In returning

page_text: the signalman's lever to its normal position the signal arm is brought back to
danger and maintained there.
In conjunction with the pulley lever j, a stop plate u is provided and in the
event of the pull o, extending between the signalman's lever and the pulley lever j,
breaking, when the signal arm is either at danger or safety, the weight of the
other pull m, and of the weight suspended thereby carries the pulley h and
lever round until the 'semaphore a assumes the vertical position indicated in
dotted lines, at which point further movement is prevented by the stop plate u.
In daylight danger is indicated by the said position of the semaphore and in the
dark by the position of the extra danger glass or spectacle e which is by the fall of
the semaphore to the vertical position brought in front of the lamp or light.
In the event of the ordinary pull breaking the weight of the extra pull and of
the suspended weight brings the semaphore to and maintains it at the danger
position.
Under the modification indicated by figure 2, the pulley h, and its lever j, is
dispensed with and the pulls m, o, are carried direct from the pulleys 8, to the
pulley f, on the axis of the semaphore a, the ends of the said pulls being secured to
opposite sides of the pulley. In the event of breakage of the pulls with this
arrangement the semaphore is prevented from being drawn upwards beyond the
horizontal danger position by a stop v, formed on or attached to the back balance b
coming in contact with the signal post and it is prevented from being drawn
downwards beyond the vertical position indicated in dotted lines by a stop w on
the semaphore itself coming in contact with the signal post.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
In a railway signal the operating apparatus consisting of a double pull having a
weight or weights at any convenient point between the signalwan's lever and the
signal post substantially as described with reference to the drawings annexed.
Dated this Sixtoonth day of Contomba Teee