Improvements in connection with the Manipulation of Railway- signals.
Year: 1896

page_text: COMPLETE SPECIFICATION.
Improvements in connection with the Manipulation of Railway-
signals.
I, JOHN THOMAS, of 10 Canon Street, Barry, near Cardiff, in the County of
Glamorgan, Fitter, 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:-
As at present arranged, the manipulation of the semaphore signals of railways
is usually effected by the operation of levers in the cabin of the signalman, such
levers being so arranged that when deflected from a vertical position a pull is exerted
upon a wire running over or under or both suitable sheaves or wheels, and leading
to a lever or levers in connection with the distant signal, and in a general way such
pull places the signal at "clear," and which returns to "danger" by the action of
a weighted lever when the pull upon the said wire is released by the signalman
returning the lever in the cabin to a vertical position, and in many cases the said
signal is situated a long distance from the cabin, which necessitates the use of a
corresponding length of wire, and the greater the length of said wire, the greater is
the degree of expansion and contraction of the same by change of temperature, and
as such expansion and contraction materially affects the movement or the extent
of the movement of the semaphore and the power needed to operate the lever in
the cabin, my invention has for its object to provide a means, and an apparatus for
carrying such means into effect, whereby a counteracting influence is caused to
automatically operate to negative the said effects of such expansion and contraction
of the line wire, and permit the cabin lever to be operated more easily, and with
less variation of power than hitherto.
In order that the apparatus constituting my invention, and the manner in which
I purpose constructing and manipulating the same may be more clearly understood
I have hereunto appended a sheet of drawings, of which
Fig. 1 is a front elevation, while Fig. 2 is a back elevation of my said invention,
substantially as I prefer to construct it, while Fig. 3 is a plan or top view of the
same.
In carrying my invention into effect I fix in any suitable position between the signal
cabin and the semaphore or other like signal to be operated upon, a metallic or
other plate A, which may conveniently be mounted upon vertical posts such as B
and B set firmly into the ground as shewn, or fixed upon brackets or the like
connected to a wall or other vertical surface, or by any other suitable means.
At a point centrally of the length of A or thereabouts, I provide a metallic or
other arm or lever C, of any suitable length, pivotted at its lower end upon a
fixed bracket such as D, and to the upper end of C is connected one end of a wire,
chain, or rod E, the opposite end of which may be connected to a lever in the signal
box or cabin, (not shewn). The arm or lever C has a slot F through which is
passed a bolt or pin G, which passes through and forms a fulcrum for a pair of
metallic or other levers or arms H and H', and to the upper ends of these is pivotally
connected by like bolts or pins J, a pair of like but shorter arms or links K and K
respectively the lower ends of H, Hi being in like manner connected by bolts or
pins L to a pair of like arms or links M and M' respectively, while the links K
and M are connected in like manner by a bolt or pin N, which passes through a
hole in the plate A and is there fixed by a nut or the like as shewn in Fig. 2. The
links K' and M¹ are connected in like manner by a similar but longer bolt or pin O,

page_text: which passes freely through a slot P in the plate A, which said slot may be of any
length suitable for the purposes it is intended to fulfil. The length of the
links K, K, M and M' are preferably such, that when the arm or lever C is
perfectly vertical as at Figs. 1 and 2, the bolts or pins J, L, N and O mark out
equal divisions of an approximately complete circle.
Referring to Figs. 2 and 3, the bolt or pin O, at the back of the plate A, passes
through one end of a slotted plate or frame R, in the slot of which is placed, ani
mounted loosely upon O, a grooved wheel or pulley S, the opposite end of R being
arranged to form a pair of jaws T, which collectively carry a wheel or sheave
having two diameters, the centre and larger of which a passes partly or wholly
through, and engages freely with, the slot P, while the peripheries of the two euds
of the smaller & rests against the plate A above and below the slot P.
Around the wheel or pulley S is passed a suitable wire or wire rope c, and thereon
retained by the frame R, one end of which said wire is connected to the signal arm
of the distant semaphore in the usual way, while its opposite end is fastened to a
suitable but preferably spiral spring d, attached to an eye bolt e, adjustably
connected by a nut f, to an angle plate g fixed to the plate A.
The manner of operation is as follows:-
A pull exerted upon the wire E from the signal cabin would deflect the arm or
lever C, and it is assumed for clearness of illustration that the extent of such
deflection of C is that shewn by a dotted line at Fig. 1, and by reason of the point N
being a fixture, such movement of C would operate the arms and links to which it
is connected, placing these in the positions shewn by the dotted lines in Fig. 1, from
which it will be seen, that the extent of the travel of the bolt or pin O, along
the slot P, is twice or thereabouts that of the distance travelled by the point G
of the lever C, or equal or thereabouts to that of the distance through which the
upper end of C has been moved, thus effecting a saving of power at the cabin lever
equal to the leverage afforded by the arm C. The distance thus traversed by the bolt
or pin O, would be the distance also traversed by the wheel S, which would exert a
pull upon the wire or wire rope c sufficient to operate the arm of the distant
semaphore or other signal, the tension of the spring d being such as to permit
this without expansion, but should the wire e by change of temperature become
shortened, the said pull thereon would be greater, when the spring d would
expand to compensate this, or contract to keep the said wire taut should this become
elongated from a like cause, and the necessary tension of the said spring d may be
always adjusted by the nut, or if necessary, by moving the plate g so as to engage
with other holes à provided in the plate A as shewn in Fig. 2.
The release of the pull upon the wire E, would permit the lever C, and the links
and arms to which it is connected, to return to their normal position, partly by
the tension of d, and partly by the usual weighted lever in connection with the
signal arm, and in order to maintain the position of the carrier R. T during its said.
movements, and to prevent possible friction between this and the plate A, is the
object and purpose of the wheel a b.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, 1 declare that what
1 claim is:
1st. In an improved method of, and means for manipulating railway signals,
the construction, use, and application of the herein described device or apparatus,
and the several parts constituting the same, fixed in any suitable position between
the signal cabin, and the signal to be operated upon, the whole connected, combined
and operating substantially as and for the purposes herein described and shewn.
2nd. For manipulating railway signals, the combination of an arm ar lever such
as C, pivotally connected at its lower end to a point D, and at its upper end by a
wire E to a lever in the signal cabin, the said arm or lever C having a slot,F,
carrying a bolt or pin G, engaging with a pair of arms H and H', pivotally connected
to links K and M, and K' and M³, the former connected to a bolt or pin N, fixed

page_text: upon a plate such as A, the latter connected by a bolt or pin O, passing through a
slot P in A, and engaging with a frame such as R T carrying at one end a wheel a b
engaging with the slot P, and at its opposite end a grooved wheel or pulley S, round
which is passed a wire rope c, connected at one end to the signal, in the usual way,
its opposite end being connected to a spring such as d, connected to an eye bolt e,
adjustably connected to a plate 9, fixed upon the plate A, the whole connected
combined and operating substantially as and for the purposes herein described and.
shewn by the appended drawings.
Dated this 26th day of September 1896.
GEO. THOS. HYDE,
1 Broad Street Buildings, London, E.C., Agent for the Applicant.