An Improved Automatic Compensator for Railway Signal Wires.
Year: 1890

page_text: Date of Application, 5th June, 1890
Complete Specification Left, 4th Mar., 1891-Accepted, 11th Apr.. 1891
PROVISIONAL SPECIFICATION.
An Improved Automatic Compensator for Railway Signal Wires.
1, JAMES PHILIP ANNETT, of "The Elins," Eastleigh, Southampton, in the
County of Hampshire, Superintendent of Signals, do hereby declare the nature of
this invention to be as follows:-
My invention consists in an improved arrangement of mechanism for actuating
signal wires in such a manner as to allow the wire to expand or contract according
to the variation of the temperature.
The essence of my invention is that when the signal is at danger the wire is
free to move according as it is acted upon by the temperature and is not in
absolute connection with the lever until the lever is worked for the purpose of
operating the signal. A downright rod preferably is arranged from the tail
of the lever, and fixed to the said rod at its lower end is a pulley wheel.
About the same level normally of the said wheel and on one of its sides is a
second wheel carried and centred in a frame, there is also centred to the same
frame that carries the last mentioned wheel but above the wheel, a pawl with a
grooved clutch on one side the other side being heavier and across the wire.
On the other side of the downright rod is a second wheel which may either be
on the same level or below as desirable. The chain runs from the signal under-
neath the last mentioned wheel, over the wheel fixed to the downright rod and
over the wheel to which the pawl is fixed and terminating in a weight, and as
the wire expands or contracts so the weight is raised or lowered and keeps the.
wire at one uniform tension.
Upon the signalman wishing to operate the signal he works his lever which
pulls the downright rod and wheel upwards, the wire being also pulled tilts the
pawl so that the grooved clutch on the left hand side grips the chain holding
it and thus forming the fulcrumm (it is of course understood that in certain cases
the groove clutch may be on the right-hand side) upon which the chain and
signal is worked, and as the frame carrying the wheel to which the pawl is
fixed is a fixture, the end nearest the rod being heavier, when the signalman
replaces his signal to danger the pawl falls and so frees the chain and thereby
allows the wire to become free again for the purpose of being accurately com-.
pensated according to the variations in the temperature.
Dated this 5th day of June 1890
JOHN P. O'DONNELL,
Agent for the said Applicant.
COMPLETE SPECIFICATION.
An Improved Automatic Compensator for Railway Signal Wires.
I, JAMES PHILIP ANNETT, of "The Elins," Eastleigh, Southampton, in the
County of Hampshire, Superintendent of Signals, 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 :--
My invention consists of an improved arrangement of mechanism for actuating
signal wires in such a manner as to allow the wire to expand or contract according
to the variation of temperature.
The essence of my invention is that when the signal is at danger the wire is free
to move according as it is acted upon by the temperature and is not in absolute
connection with the lever until the lever is worked for the purpose of operating the

page_text: A. downright rod preferably, is arranged from the tail of the lever, and fixed in
the said rod at its lower end is a pulley wheel. About the same level normally as
the said wheel and on one of its sides, is a second wheel carried and centred in a
frame. There is also centred to the same frame that carries the last mentioned
wheel, but above the wheel a pawl with a grooved clutch on one side, the other side
being heavier and across the wire. On the other side of the downright rod is a
second wheel which is approximately fixed a little higher than the other wheels.
The chain runs from the signal underneath the last mentioned wheel, over the wheel
fixed to the downright rod and over the wheel to which the pawl is fixed and
terminates in a weight. As the wire expands or contracts so that weight is raised
or lowered and keeps the wire at one uniform tension.
Upon the signalman wishing to operate the signal he works his lever which pulls
the downright rod and wheel upwards, the wire being also pulled tilts the pawl so
that the grooved clutch on the left hand side grips the chain holding it, thus forming
the fulcrum upon which the chain and signal is worked, and as the frame carrying
the wheel to which the pawl is attached is a fixture, the end nearest the rod being
heavier, when the signalman replaces his signal to danger the pawl falls and so frees
the chain and thereby allows the wire to become free again for the purpose of being
accurately compensated according to the variation of temperature.
:-
In order that my invention may be more readily understood and carried into
effect will proceed to describe the drawing hereunto annexed. The same letters
refer to the same parts in the several figures of the drawing
Figure 1 is a side view of the lever showing the application of the apparatus.
Figure 2 is an enlarged view of the apparatus itself.
Figure 3 is a section A, B of Figure 2.
Figure 4 is a plan of Figure 2.
A is the actuating lever in the signal box in its normal position; B is the worked
over position of the said lever; C is the downright rod from the tail of the lever;
D is the wheel or pulley fixed in the downright rod; E is the wheel at the right
hand side of the downright rod; F is the wheel at the left hand side of the down-
right rod; G is the light or grooved end of the clutch fixed over the wheel F ;
H is the heavy end of the said clutch; I is the chain, and J the weights to com-
pensate the wire.
It is obvious that the positions of the wheels may be changed or the position of
the clutch changed, that is to say that the signal may be fixed on the other side of
the lever, or any such modification.
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 :-
For compensating for the expansion and contraction of railway signal wires owing
to the variation of temperature, the apparatus substantially described and illustrated
in Figures 1 to 4 of the drawing annexed.
Dated this 4th day of March 1891
JOHN P. O'DONNELL,
2, Great George Street, Westminster, London, S. W.,
Agent for the said Applicant.