IMPROVEMENTS IN RAILWAY • SIGNAL APPARATUS "
Year: 1882

page_text: LETTERS PATENT to William Robert Sykes of Nunhead in the County of
Surrey Telegraph Engineer for an Invention of "IMPROVEMENTS IN RAILWAY
• SIGNAL APPARATUS
"
PROVISIONAL SPECIFICATION left by the said William Robert Sykes at
the Office of the Commissioners of Patents on the 13th December 1882.
WILLIAM ROBERT SYKES of Nunhead in the County of Surrey Telegraph
Engineer "IMPROVEMENTS IN RAILWAY SIGNAL APPARATUS
"
My Invention consists of improvements in railway signal apparatus.
I employ a strong spring affixed alongside one of the rails of the railway at the
place where it is required to work a signal, the said spring being so placed that
the wheels of a train in passing act upon it and thereby complete the electric
circuit of a line in which are one or more electro magnets or solenoids; the
armatures of these electro magnets or the cores of these solenoids are thus moved
and automatically work the signal arms, lamps or other devices with which they
are connected. Or instead of the spring being made to complete the electric
circuit of a line when acted upon by a passing train it may be made to break
a circuit which was previously complete or to short circuit a line and thereby
render the electro magnets or solenoids inactive.
According to one arrangement I connect the spring at one end and preferably
by a knuckle or other suitable joint to a bracket bolted to the web of the rail and
I connect the other end of the spring, preferably by another similar joint, to a bolt
which passes into a closed iron box and works in guides therein. Upon the end
of this bolt is a brass or other metallic knob adjustable in the bolt by means of a
set nut or otherwise. Opposite the knob are four or other desired number of spring
contacts mounted upon a block of ebonite or other insulating material. These
spring contacts are all in metallic connection with the line wire. As a train passes
over the spring the latter is depressed by the wheel flanges and the end to which
the bolt is fitted is thereby caused to slide towards the box, the result of which is
that the knob comes into contact with the four contacts and thus completes (through
the rail to earth) the electric circuit necessary for working the signal arms, lamps
Daina 37

page_text: or other devices. As the contact between the knob and springs is a rubbing
contact, the parts are kept free from dirt. Should any of the spring contacts
break, the apparatus will still work one contact being sufficient to complete the
circuit. In some cases I connect some of the spring contacts with the line wire
or wires and the others with earth so that when the knob rubs against them
the circuit to earth is through these contacts instead of through the rails as first
described.
According to another arrangement I attach the spring to the rail as before, but
I insulate it therefrom, and I connect the bolt permanently with the line wire.
In this case when the train passes over the spring the wheel makes metallic contact
between the spring and the rail so that the electric circuit to earth is completed
through the wheel and rail. With this arrangement the box described in the first
arrangement is not necessary.
The electro magnets or solenoids which are employed in connection with the
spring and arrangements above described may be used. to lock block-instruments
and thereby prevent a signalman using his signal a second time for another train
to pass until the first train by passing over the spring releases the lock; or they
may be used for putting up signals behind a train; or for various other purposes
in connection with railway Signals.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Robert Sykes in the Great Seal Patent Office on the
13th June 1883.
:
WILLIAM ROBERT SYKES of Nunhead in the County of Surrey, Telegraph
Engineer "IMPROVEMENTS IN RAILWAY SIGNAL APPARATUS
"
My invention consists of improvements in railway signal apparatus.
I employ a strong spring affixed alongside one of the rails of the railway at the
place where it is required to work a signal, the said spring being so placed that
the wheels of a train in passing act upon it and thereby complete the electric
circuit of a line in which there are one or more electro-magnets or solenoids; the
armatures of these electro-magnets or the cores of these solenoids are thus moved
and automatically work the signal arms, lamps or other devices with which they
are connected. Or instead of the spring being made to complete the electric circuit
of a line when acted upon by a passing train it may be made to break a circuit
which was previously complete or to short circuit a line and thereby render the
electro magnets or solenoids inactive.
According to one arrangement which is represented in Figure 1, a being the rail
and 6 the spring, I connect the spring at one end and preferably by a knuckle or
other suitable joint to a bracket c bolted to the web of the rail and I connect the
other end of the spring, preferably by another similar joint, to a bolt d which
passes into a closed iron box e and works in guides therein. Upon the end of this
bolt is a brass or other metallic knob f adjustable in the bolt by means of a set
nut or otherwise. Opposite the knob are four or other desired number of spring
contacts g mounted upon a block of ebonite or other insulating material. These
spring contacts are all in metallic connection with the line wires. As a train
passes over the spring 6 the latter is depressed by the wheel flanges and the end
to which the bolt d is fitted is thereby caused to slide towards the box e, the result
of which is that the knob f comes into contact with the contacts g and thus
completes the electric circuit necessary for working the signal arms, lamps or other
devices. As the contact between the knob f and spring contacts g is a rubbing
contact, the parts are kept free from dirt. Should any of the spring contacts break,
the apparatus will still work, one contact being sufficient to complete the circuit.
In some cases I connect some of the spring contacts with the line wire or wires
and the others with earth so that when the knob rubs against them the circuit
to earth is through these contacts instead of through the rails as first described.
According to another arrangement represented in Figure 2 1 attach the spring b
to the rail a as before but I insulate it therefrom and I connect the bolt d
permanently with the line wire. The insulation of the spring from the rail is
shown as effected by the interposition between the rail and the bracket c and
between the rail and the guide piece e (which takes the place of the box e
Figure 1) of a piece of insulating material as shown by the black lines i; the bolts
which secure the bracket c and the guide piece e to the rail should also pass
through insulating collars. In this arrangement when the train passes over the
spring b the wheel makes metallic contact between the spring and the rail so that
the electric circuit to earth is completed through the wheel and rail. The box e.
shown in Figure 1 is not necessary with this arrangement.
Figure 3 represents an arrangement in which not only is the spring b insulated
from the rail a to which it is attached, but the rail a is itself insulated from the
rails before and behind it and from its supporting chairs. I prefer this arrange-
ment in cases where it is desired that the tread of the wheel and not its flange

page_text: should act upon the spring b; the spring need project above the rail only just
sufficient to ensure the tread of the wheel acting upon it; the electric circuit is
completed between the insulated rail and the spring by the tread of the wheel and
another electric circuit is completed from the spring through the wheel and the
axle of the carriage to the rail forming the other side of the line; either or both
of these circuits can be utilized as will be readily understood. The black lines k k
indicate insulating material to insulate the rail a from the fish plates. which
connect it with the adjoining rails; represent insulating material between the
rail a and the chairs, and m m insulating material between the chairs and the
sleepers to ensure the insulation of the rail a from earth in case the insulation
between the rails and chairs is broken.
.
The electro-magnets or solenoids which are employed in connection with the
spring and arrangements above described may be used to lock block instruments
and thereby prevent a signalman using his signal a second time for another train
pass until the first train by passing over the spring releases the lock; or they
may be used for putting up signals behind a train, or for various other purposes
in connection with railway signals.
to
Having now described the nature of my said invention and in what manner
the same is to be performed I declare that I claim:
The several arrangements substantially as herein before described for working
railway signals by means of a spring affixed to one of the rails of the railway so as
to be acted upon by a passing train and thereby complete the electric circuit, of.
a line in which are one or more electro-magnets or solenoids, or break a circuit
previously complete or short circuit a. line, substantially as and for the purposes
set forth.
In witness whereof I the said William Robert Sykes have hereunto set my
hand and seal this twelfth day of June One thousand eight hundred and