A NEW SELF-ADJUSTING APPARATUS FOR RAILWAY SIGNALS, APPLICABLE ALSO TO OTHER PURPOSES
Year: 1865

page_text: PROVISIONAL SPECIFICATION left by George Mussell at the Office of the
Commissioners of Patents, with his Petition, on the 20th October 1865.
I, GEORGE MUSSELL, of Linslade, in the County of Bucks, do hereby declare
the nature of the said Invention for "A NEW SELF-ADJUSTING APPARATUS FOR
RAILWAY SIGNALS, APPLICABLE ALSO TO OTHER PURPOSES," to be as follows:-
This Invention relates to mechanical means or apparatus to be employed
in connection with railway signal apparatus for compensating the elongations
and contractions which occur in the wire usually employed for transmitting
the motion of the hand lever or other form of apparatus operated or set in
motion by the signal man for the purpose of moving or changing the position
of a semaphore arm, disc, or other form of signal placed at a distance from
the signal man, and usually distinguished by the name of a "distant signal,"
and there are occasionally several of such "distant signals" coupled or
connected together. The use or employment of wire (generally galvanized
iron wire) involves the necessity for providing against the effects of contraction
and expansion from changes of atmospheric temperature, as also from strain-
ing and other causes, and inasmuch as upon the position of the semaphore
arm or other signal and the certainty of its assuming the position desired by
the signal man in accordance with a code of rules employed in connection
with the working of the line, depends the usefulness of such "distant signals"

page_text: "
and the safe conduct of the traffic, the more especially as the "distant signals'
are most frequently out of the signal man's view, a self-acting and constantly
ready means of adjusting the apparatus in compensation of change of condition
of the wire and connections is of the first importance in efficient railway
management. By the present Invention I effect a perfectly self-acting
system of adjustment of "distant signal" apparatus through or by means of
the combination of a chain or chains, pulleys, weights, and nipping studs or
angular stop pins which may be attached to the "distant signal" post, and
connected with and interposed between the signal wire near the ground and
the semaphore arm, disc, or other signal. In applying my Invention to
semaphore arm "distant signals "I prefer to fit upon the axis or pivot of the
arm a double lever or spanner, to the one end of which is usually connected
the vertical rod employed for moving the arm. This rod I prefer to employ
for overbalancing the semaphore arm through the application of weights
at its lower end which if the apparatus were otherwise free to act would
keep the semaphore arm on to "danger." Then I connect to the other
end of the double lever or spanner a carriage or frame, having a pulley
mounted therein, over which à chain is made to pass in a 'bight on its way
from the junction with the signal wire (near the bottom of the post) to the
bottom of the post; again where the other end of the chain is made to carry
a sufficient load or number of weights requisite to strain the chain and produce
the required tightening or holding and releasing or slipping actions (as the
condition of the connecting wire may require) the chain referred to as first
going up, then over the top pulley, and then down, is connected at one end
with the signal wire at a sufficient distance from the signal post; it is then
carried under a pulley and up the side of the post over the pulley mounted
in the carriage that is connected with the lever arm or spanner fixed on the
axis of the semaphore, from thence the chain passes down the post either into
a pit or boxing (in which the weights connected with the end of the chain are
free to move up or down), or the requisite weight or strain may be obtained
by connection with a loaded frame or a loaded lever arm. But between the
pulley at the head of the post and the weights at the lower end of the chain
it is made. to pass over three or more studs, one of which is placed out of
the line of the other two, and forming in relation to each other a triangle,
so that the chain is made to pass through between them, and when loaded or
strained by being held tightly above or at its upper end and loaded or weighted
below or at its lower end, the chain becomes gripped and held fast therein.
Below the studs. a pulley may be introduced, around which a turn of the
chain may be taken on its way downward to render its
action more free or

page_text: to change its direction. Thus when the semaphore arm is dependent and
concealed within the signal post, indicative of the line being "clear," the
top carriage and pulley over which the chain passes at the top of the post is
pulled downward to its lowest position, and the signal wire and the chain is
kept strained so as to retain the semaphore firmly in its position as the weight
or overbalancing load suspended on the vertical rod (connected with the
double lever or spanner) is ready, upon the wire and chain being released
by the signal man, to bring the semaphore arm from the dependent vertical
position to the horizontal extended position indicative of "danger," and
employed generally as a "stop" signal. When the long length of signal
wire has become extended so that by the movement of the signal man's lever
the semaphore arm is not brought to its proper position, there would be an
amount of slack left in the chain between the top pulley and the lower
ends of the chain. Besides the use and application of apparatus according
to my Invention for "distant signals as described, it may be applied to the
working of a compound system of signals and "repeaters," and for working
level crossing gates and for other similar purposes in connection with railways
and wherever such adjustments as those herein described are useful or
necessary in connection with the transmission of motion between distant
points or from one place to another at a distance therefrom.