IMPROVEMENTS IN ELECTRIC BLOCK SIGNALS AND ELECTRIC LOCKING APPARATUS FOR LEVERS WORKING SEMAPHORES AND POINTS ON RAILWAYS, THE LATTER PART OF SUCH IMPROVEMENTS BEING APPLICABLE TO THE SECURE CLOSING OF BUILDINGS, STORE-ROOMS, AND SAFES." PROVISIONAL SPECIFICATION.
Year: 1882

page_text: LETTERS PATENT to James Radcliffe, of Retford, in the County of Nottingham,
Telegraph Engineer, for an Invention of "IMPROVEMENTS IN ELECTRIC BLOCK
SIGNALS AND ELECTRIC LOCKING APPARATUS FOR LEVERS WORKING
SEMAPHORES AND POINTS ON RAILWAYS, THE LATTER PART OF SUCH
IMPROVEMENTS BEING APPLICABLE TO THE SECURE CLOSING OF BUILDINGS,
STORE-ROOMS, AND SAFES."
PROVISIONAL SPECIFICATION. left by the said James Radcliffe at the Office
of the Commissioners of Patents on the 13th January 1882.
JAMES RADCLIFFE of Retford in the County of Nottingham, Telegraph Engineer.
IMPROVEMENTS IN ELECTRIC BLOCK SIGNALS AND ELECTRIC LOCKING APPARATUS
FOR LEVERS WORKING SEMAPHORES AND POINTS ON RAILWAYS, THE LATTER
PART OF SUCH IMPROVEMENTS BEING APPLICABLE TO THE SECURE CLOSING of
BUILDINGS, STOREROOMS, AND SAFES.
My electric locking apparatus for levers is designed with the view to prevent
the signalman of a railway from lowering his signal or shifting his points until he
bas received the signal "line clear" from the station or signal box in advance.
am aware that there are many appliances designed with this view, but in my
improvements I ensure the locking of the signal lever by means of a vertical or
nearly vertical bolt or bar, suspended from its upper end over a projecting tongue
or shoe attached to and forming part of the clip-lock of the lever. A link attached
to the armature of an electro-magnet is connected with the bolt or bar. The
electromagnet is connected by the conducting wire with the block-signalling
telegraph instrument at the station, or signal box in advance and in such a manner
that an electric current is only passed to the electro-magnet when the block-
signalling instrument is at line clear." This electric current may be passed
direct from the station in advance, or, which I find preferable, by means of any
ordinary relay.
.
The effect of the current passing through the electromagnet is to attract its
armature and thus draw the bolt or bar free from the end of the projecting tongue

page_text: or shoe of the clip-lock of the lever. The signalman is then able to move his lever
and lower his semaphore or other signal, or shift his points if the lever is one that
works points. When the line is "blocked" at the advance station, or signal box,
the bolt or bar hangs down in its vertical or nearly vertical position over the end
of the tongue or shoe of the clip-lock of the lever, and by its rigidity prevents the
signal being moved, whatever force may be exercised by the signalman.
"
The receiving portion of the "block" telegraph instrument working from the
station, or signal box in advance is connected and adjusted in such a manner that
only a " line clear current from it will release, the locking apparatus already
described. This "line clear" current is transmitted by means of a small local
battery and a "polarised" relay or other suitable arrangement.
The whole of the "locking" apparatus is enclosed in a strong metal case and
screwed down to the lever frame so that it cannot be tampered with. The signal-
man at the rear station is prevented from unlocking his own signal by a spring and
contact point inserted in the local circuit of the lock and attached to the commu-
tator of the block signalling instrument in such a manner as to become disconnected
by any motion of the latter. There is also a spring contact attached to the back
of the signal lever, which disconnects the battery wire of the block signalling
" cannot
instrument when the lever is pulled off, so that the signal "train on line
be given until the outside semaphore has been put to danger.
The second part of my Invention consists of an arrangement specially applicable to
single line working.-Two light brass levers are pivotted at the centre and carry at
their lower extremities soft iron armatures, which are attracted by two electro magnets
whenever a current passes through the latter. Attached to the upper extremities
of the levers are two contact springs on each. One of the contact-springs on each
is insulated from its respective lever. The soft iron armatures are kept away from
the electro magnets, and the two uninsulated springs kept in contact with two fixed
studs by means of adjustable springs when no current is passing but on either of the
armatures being attracted the uninsulated spring leaves its stud and the insulated
spring comes in contact with a stud connected with the earth. The insulated spring
is permanently connected with the "line" spring of the "down line" instrument.
The earth terminal of the "up line instrument instead of being put direct to earth
is connected to the lever and thence through the uninsulated spring and its stud to
earth when its armature is not attracted. By this arrangement it is impossible
either to give or receive a signal for an "up" train after the signal for a "down
train has been given and acknowledged, the earth wire of the "up" instrument
being disconnected, and any attempt to alter the acknowledged signal without the
permission of the station in advance would result in the battery being short
circuited through the insulated spring and its stud.
"

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said James Radcliffe in the Great Seal Patent Office on the 13th
July 1882.
JAMES RADCLIFFE of Retford in the County of Nottingham Telegraph Engineer
IMPROVEMENTS IN ELECTRIC BLOCK SIGNALS AND ELECTRIC LOCKING APPARATUS
FOR LEVERS WORKING SEMAPHORES AND POINTS ON RAILWAYS, THE LATTER
PART OF SUCH IMPROVEMENTS BEING APPLICABLE TO THE SECURE CLOSING Of
BUILDINGS, STOREROOMS, AND SAFES.
The first part of my Invention is designed with the view to prevent the signal-
man of a railway from lowering his signal or shifting his points, until he has
received the signal " line clear" from the station or signal box in advance. I am
aware that there are many appliances designed with this view; but, in my
improvements I ensure the locking of the signal lever by means of a vertical or
nearly vertical bolt or bar, suspended from its upper end over a projecting tongue
or shoe, attached to and forming part of the clip-lock of the lever. A link
attached to the armature of an electro-magnet is connected with the bolt or bar.
The electro-magnet is connected by the conducting wire with the block-signalling
telegraph instrument at the station or signal box in advance, and in such a manner
that an electric current is only passed to the electro-magnet when the block-
signalling instrument is at "line clear." The electric current may be passed direct
from the station in advance, or, which I find preferable, by means of any ordinary
relay. The effect of the current passing through the electro-magnet is to attract its
armature and thus draw the bolt or bar free from the end of the projecting tongue
or shoe of the clip-lock of the lever. The signalman is then able to move his
lever and lower his semaphore or other signal, or shift his points if the lever is one
that works points. When the line is "blocked " at the advance station or signal
box, the bolt or bar hangs down in its vertical or nearly vertical position over the
end of the tongue or shoe of the cliplock of the lever, and by its rigidity prevents
the signal being moved, whatever force may be exercised by the signalman.
Fig. 1. shows the signal locking apparatus, which consists of a steel bolt or
bar A, suspended nearly vertically over a projection from the back of the clip-
lock D of the signal lever. B is the armature of the electro-magnet E, and is
jointed by means of a short connecting rod C to the upper part of A, so that a very
small motion at B is sufficient to move A clear of D and enable the latter to be
raised by means of the clip F, and the lever to be pulled off.-The whole is enclosed
in a strong metal case and screwed down to the signal frame so that it cannot be
tampered with.
"
The lock is actuated by means of a local battery of two or three cells, the circuit
of which is completed by a polarised relay inserted in the receiving portion of the
block instrument, working from the station in advance and connected and adjusted
in such a manner that only a "line clear current from the station in advance
will release the lock. Fig. 2 shows the signal locking apparatus with a diagram
of the electrical connections. The signalman at the rear station is prevented from
unlocking his own signal by the spring X and contact point Y inserted in the local
circuit of the lock, and attached to the commutator of the block signalling instru-
ment in such a way as to become disconnected by any motion of the latter. There
is also a spring contact Q attached to the back of the signal lever (as shown in
both Figures) which disconnects the battery wire of the block signalling instru-
ment when the lever is pulled off, so that the signal "train on line " cannot be
given until the outside semaphore has been put to danger. Fig. 2 also shows the

page_text: second part of my Invention, which is an arrangement specially designed for single
line working. G'is a light brass lever pivotted in the centre, and carrying at its
upper extremity, a soft iron armature H which is attracted by the electro-magnet I
whenever a current passes through the latter. Attached to the lower part of G
are contact springs K and L, of which L is insulated from G. H is kept away
from I, and K kept in contact with the fixed point M by means of an adjustable
spring when no current is passing; but when a current is passed then H is
attracted, K leaves M and L comes in contact with the fixed point N. The
connexions are arranged as follows:-The apparatus being attached to the "down
line "instrument at
station; the earth terminal of the " up line " instrument,
instead of being put direct to earth, is connected to G and thence through M to
earth.. L and Ñ are connected with the line and earth springs respectively of the
"down line" instrument. It is thus impossible either to give or receive a signal
for an "
up train
after the signal for a "down train " has been given and
acknowledged, the earth wire of the " up line" instrument being disconnected; and
any attempt to alter the acknowledged signal without the permission of the station
in advance would result in the battery being short circuited through L and N, and
would therefore prove futile.
Having thus described the nature of my said Invention, and the best means I
am acquainted with for carrying the same into effect, I wish it to be understood
that what I claim is ;-
.
1st. The electric signal locking apparatus.
2nd. The block signalling apparatus.
3rd. The block signalling apparatus as specially adapted to single line
working.
4th. The combination of the electric signal locking apparatus with the block-
signalling instruments. All substantially as described.
In witness whereof, I, the said James Radcliffe, have hereto set my hand
and seal this Twelfth day of July, in the year of our Lord One
thousand, eight hundred and eighty two.
JAMES RADCLIFFE (10)
JAMES RADCLIFFE
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