Improvements in Co-acting Apparatus for Railway Signalling Purposes.
Year: 1894

page_text: COMPLETE SPECIFICATION.
Improvements in Co-acting Apparatus for Railway Signalling
Purposes.
I, ARTHUR GEORGE EVANS, of 116 Palace Chambers, Bridge Street,
Westminster, in the County of Middlesex, Civil 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 :-
My invention relates to certain improvements in the construction and arrange-
ment of signalling apparatus for the purpose of controlling any one or more signals
by any one or more other signals, or of controlling any one or more signals from
any two or more signal cabins or points of concentration. It further relates, and
which is the most common use of co-acting apparatus, to controlling any one signal,
say a distant signal, by any one or more arms and from any one or more signal
cabin or cabins.
My invention can be carried out by adapting the ordinary balance lever
co-acting plate which had been previously used for arms that were not counter-
balanced to work arms discs and spectacles that are weighted or counter-balanced.
Briefly, the object of my invention is to produce an apparatus which will depart
as little as possible from the standard forms of balance plates heretofore fixed upon
signal posts so that while conforming to the regulations of counter-balanced arms,
discs or spectacles, would yet overcome certain defects now common in apparatus
applied for the purposes of slotting or controlling signals. I also gain the
advantage that the last lever which is worked for the purpose of lowering the
controlled signal is not dependent on the wire of the first wire that is worked, that
is to say, it does not tend to undo the operation performed by the first lever worked.
My apparatus also, as is usual with all co-acting apparatus, provides that in the
event of a fracture of any of the connections the controlled signal flies to the
danger" attitude.
66
Also either of the counter-balance levers on being returned to the normal
attitude also replaces the controlled signal to the "danger" attitude.
My apparatus is not dependent on weights or gravity to move the controlled
signal to the "safety" attitude.
In order that my invention may be better understood and more readily carried
into effect I will proceed to describe the drawings hereunto annexed, in which
similar letters refer to like parts in the several figures.
Figure 1 represents a plan of my apparatus.
Figure 2 represents a front view of my apparatus with one of the balance levers
in its worked position.
Figure 3 represents a side view.
Figure 4 is a front view of a signal post showing the arrangement of and the
connections from the apparatus to the arms.
•
Figure 5 is a diagram showing the connections from the cabins X and Z to the
signal arms.
a is the main casting or carriage in which the balance levers themselves are
supported, bis the fulcrum or spindle on which the balance levers work, c is the
balance lever next the signal post operated by the near cabin X, this lever
operates the stop signal to through its upright rod c'; d is the intermediate lever
directly connected by the upright rod d to the distant arm v, e is the outside
balance lever operated from the distant lever in the far cabin Z, f is a friction
roller bolted to the lever c, g is a friction roller bolted to the lever e, h is a clip
bolted to the intermediate lever d with a downward projection h' terminating in a

page_text: The cradle
cotter and nut. The projection forms a support for a cradle or rocking piece j
a nut preventing the said cradle piece j from falling. One side is adjacent
to the roller f and the other side is adjacent to the roller g.
piece is free to move sideways, the cross pieces act as guides for the
cradle, the projection passing between them and maintaining; in its position.
The action of my invention is as follows:-
The intermediate lever d which directly operates the distant arm v can only be
moved to operate the said arm by the joint action of the stop signal w through its
lever c and the distant signalman in the cabin Z operating the lever e.
If the
lever c operating the stop signal is worked first, in its downward action the roller f
comes in contact with the side piece of the cradle j and tilts it sideways moving
the other end piece into direct connection with the roller g attached to the
balance lever e, the roller then travelling down the curved edge of j', by this action
the stop signal w is deflected to the " safety attitude." When now the signalman
in the cabin Z to which the distant signal applies operates the balance lever e,
the
roller f being in direct connection with the side piece moves the cradle j down-
wards thereby also moving the middle or intermediate lever d downwards, also
through acting on the nut attached to the projection of the piece bolted to
the intermediate lever d the action of d moving downwards deflects the distant
signal to the "safety" attitude. If either of the levers e or c are replaced to the
normal position the said action frees the cradle ; and allows the intermediate
lever d also to assume the normal attitude the distant signal arm v thereby being
placed to "Danger," by the movement of either one or other of the outside levers c
or e being replaced normal.
Therefore, no matter what the conditions may be in the order of action of the
two signalmen X or Z my apparatus compels their joint action, as hereinbefore
described, before the distant or controlled signal is given "All clear
"
or moved
to the "safety" attitude. On the other hand either one of the signalmen may
set the distant or controlled signal to the "danger" attitude independent of the
other.
The apparatus as herein before described is a single co-acting apparatus, but I
would have it distinctly understood that I have only described this said single
co-acting apparatus as a simple example as applied to one of its uses, for it is
obvious that a signal may be controiled from any number of signal cabins and
again that any number of signals may jointly control the action of any one or more
other signals; further my invention is applicable to effecting the joint control of
any one or more signals from any two or more signal cabins and effecting the joint
control of any one or more signals by any one or more other signals.
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 :-
In co-acting apparatus for railway signalling purposes, the arrangement of
friction rollers, such as f and g, in the counter-balance levers, in combination with a
cradle or rocking piece such as j suspended from the lever of the controlled signal,
the whole operating substantially in the manner, for the purposes herein described,
and as illustrated in the accompanying drawing.
Dated this 27th den of Amil 1904
JOHN P. O'DONNELL,
70. & 71, Palace Chambers, Bridge Street, Westminster, London, S. W.,
Agent for the said Applicant.