Year: 1897

page_text: I, WILLIAM FREDERIC RENTON, of No. 6, Claremont Crescent, Northumberland
Road, Sheffield, in the County of York, Engineer, do hereby declare the nature of
this invention to be as follows:-
In many cases a railway signal has to be placed under the control of two or more*
separate, and, it may be, distant signal-men, so that the semaphore arm cannot be
lowered to "safety" unless both or all the signal-men pull over their levers for that
purpose.
My invention relates to apparatus for working the signal under these conditions.
For this purpose assuming that the signal is to be under the control of two signal-
men the ordinary balance weight employed to raise the semaphore arm is fixed on
one arm of a lever having mounted on its other arm a pulley over which passes a
wire, chain or other pull attached to both the semaphore signal levers. A pin on the
loaded arm of the lever is engaged in a slot or forked gab at the lower end of the
vertical rod which works the semaphore arm, this slot or gab being of such length
that when only one of the two signal levers is pulled over the pin is moved up the
slot or gab without raising the vertical rod, but when both the signal levers are
pulled over, the pin on the loaded lever, being moved through twice the distance,
raises the vertical rod, lowering the semaphore arm. When either signal lever is
moved back to "danger" position, the pin descending the slot or gab allows the
loaded arm of the lever to descend, and the semaphore arm to rise to "danger."
When the signal has to be controlled by more than two signalmen, as for instance by
four, the pull from No. 1 cabin is led over one pulley on the loaded lever then down
under a pulley mounted on pull No. 2, again up and over a second pulley on the lever,
then down under a pulley mounted on pull No. 3 and finally up and over a third
pulley on the lever and thence away as pull No. 4. By this arrangement each of the
four pulls moves the lever only over one fourth of the distance required to make
the pin on the lever raise the signal rod, all 4 must conspire to effect the full
movement.
Dated this 36th day of October 1897

page_text: An Improvement in Railway Signal Apparatus.
I, WILLIAM FREDERIC RENTON, of No. 6, Claremont Crescent, Northumberland
Road, Sheffield, in the County of York, 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 :-
In many cases a railway signal has to be placed under the control of two or more
separate, and it may be, distant signalmen, so that the semaphore arm cannot be
lowered to indicate safety unless both or all the signalmen pull over their levers for
that purpose. My invention relates to apparatus for working the signal under these
conditions as I shall describe referring to the accompanying drawings.
Fig. 1 is a side view and
Fig. 2 is an end view of a signal lever and its connections arranged according to
my invention so that the signal is under the control of two separate signal-men.
Figs. 3 and 4 are corresponding views shewing the arrangement for control of the
signal by three signal-men.
Referring first to Figs. 1 and 2 the ordinary balance weight B, employed to raise
the semaphore arm to indicate danger, is fixed on one arm of a lever A having
mounted on its other arin a pulley F over which passes a wire I J which is led over
suitable guide pulleys G and H and has its ends attached to both the separately
operated, and it may be distant signal levers. A pin E on the loaded arin of the lever
is engaged in a slot or forked gab at the lower end of the vertical rod C which is
connected in the usual way to a lever arm projecting beyond the fulcrum of the
semaphore arm. This slot or gab is of such length that when only one of the two
signal levers, is pulled over drawing I or J the lever A takes the position A¹ and the
pin E is moved up to the end of the slot or gab without raising the vertical rod C,
but when both the signal levers are pulled over, drawing both I and J, the
lever A is raised to the position A2 and the pin C then raises the vertical rod C
lowering the semaphore arm to indicate safety. When either signal lever is moved
back to "danger" position, releasing I or J, the pin E descends in the slot or gab
allowing the loaded arm of the lever to descend, raising the semaphore arm to
indicate "danger."
When the signal has to be controlled by three signal-men, the arrangement shewn
in Figs. 3 and 4 is adopted. The lever A has mounted on its end two pulleys F and L.
and a cord or chain O, which has its end attached to A at K and M, is passed round
these pulleys and three pulleys G, H and I which are mounted in yokes attached to
the three pulls G₁ H₁ and I leading from the three separate signal levers. The
stroke of each of these signal levers is such that when it is pulled over, the lever A is
raised to A¹, when two are pulled over, it is raised to A2, and it is not until the third
is also pulled over, that the lever is raised to A3, the pin E raising the rod C and so
lowering the semaphore arm to indicate safety.
Similar arrangements of pulleys may obviously be employed when a signal has to
be controlled by a greater number of separate operators.
Having now particularly described and ascertained the nature of this invention,
and in what manner the same is to be performed, I declare that what I claim
is :—
1. In combination with the loaded lever and vertical rod employed for operating
a semaphore railway signal, a pulley, mounted on the lever, and a cord or chain
passing over the pulley, and having its ends attached to two separate signal pulls,

page_text: the pin of the lever being engaged in a slot of the vertical rod of such length as to
allow free stroke of the pin due to one of the pulls, substantially as described.
2. In combination with the loaded lever and vertical rod employed for operating
a railway semaphore signal, two or more pulleys mounted on the lever, a cord or
chain having its ends attached to the lever and passed over these pulleys and other
pulleys in number one greater than the pulleys on the lever, each of these latter
pulleys being mounted in a yoke attached to a separate signal pull, substantially as
described.