IMPROVEMENTS IN THE MEANS OF EFFECTING INSTANT COMMUNICATION BETWEEN DISTANT POINTS
Year: 1854

page_text: LETTERS PATENT to Thomas Thurlby, of Guildford Street East, Spa Fields,
in the County of Middlesex, for the Invention of "IMPROVEMENTS IN THE
MEANS OF EFFECTING INSTANT COMMUNICATION BETWEEN DISTANT POINTS OF
Sealed the 22nd March 1854, and dated the 27th January 1854.
PROVISIONAL SPECIFICATION left by the said Thomas Thurlby at the
Office of the Commissioners of Patents, with his Petition, on the 27th
January 1854.
I, THOMAS THURLBY, of Guildford Street East, Spa Fields, in the County of
Middlesex, do hereby declare the nature of the said Invention for "IMPROVE-
THE MEANS OF EFPECTING INSTANT COMMUNICATION BETWEEN DISTANT
POINTS OF RAILWAY TRAINS" to be as follows:-
My Invention consists in transmitting signals of communication from the
guard to the engine driver of a railway train by means of compressed air
conveyed from one point to the other. To effect this communication, I fit the
several carriages of a train with suitable pipes, placed under the frames or in
other convenient part. These pipes are fitted at either end with couplings,
and connected by flexible or other pipes, which are united when a train is
made up. I place a whistle or other instrument whereby sound is produced
at the point to which the signal is to be conveyed, and in connection with the
tube before mentioned.

page_text: At the other end of the train or intermediate I place the apparatus by which
the signal is produced. For this purpose I employ an air pump, whereby I
condense air in a chamber or reservoir. I connect this reservoir with the tube
of communication, which is fitted with suitable stop-cocks to permit or suspend
the emission of air at pleasure. The air chamber is always kept charged with
condensed air in readiness for use; it is therefore simply necessary that the
guard or other person in charge should open the communication between the
reservoir and the main tube, when an instantaneous audible signal will be
produced by the whistle at the opposite end. A code of conventional signals
may be arranged by making the sounds of more or less duration, or combination
of shorter with longer durations of sound.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed by
the said Thomas Thurlby in the Great Seal Patent Office on the 27th July
1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
THURLBY, of Guildford Street East, Spa Fields, in the County of Middlesex,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of January, in the year of our Lord
One thousand eight hundred and fifty-four, in the seventeenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Thomas Thurlby, Her special licence that I, the said Thomas Thurlby, my
executors, administrators, and assigns, or such others as I, the said Thomas
Thurlby, my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE MEANS OF
EFFECTING INSTANT COMMUNICATION BETWEEN DISTANT POINTS OF RAILWAY TRAINS,"
upon the condition (amongst others) that I, the said Thomas Thurlby, by an
instrument in writing under my hand and seal, should particularly describe
and ascertain the nature of the said Invention, and in what manner the same
was to be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date of the
said Letters Patent.

page_text: NOW KNOW YE, that I, the said Thomas Thurlby, do hereby declare the
nature of my said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement,
reference being had to the two Sheets of Drawings hereunto annexed, and to
the letters and figures marked thereon (that is to say):
-
My Invention consists in transmitting signals of communication from the
guard to the engine driver of a railway train by means of compressed air
conveyed from one point to the other. To effect this communication I fit the
several carriages of a train with suitable pipes placed under the frames or in
other convenient part. These pipes are fitted at either end with couplings,
and connected by flexible or other pipes, which are united when a train is
made up. I place a whistle or other instrument whereby sound is produced
at the point to which the signal is to be conveyed, and in connection with the
tube before mentioned. At the other end of the train I place the apparatus
whereby the signal is produced, or it may occupy an intermediate position in
the train. For this purpose I employ an air pump whereby I condense air in a
chamber or reservoir. I connect this reservoir with the tube of communication,
which is fitted with suitable stop-cocks to permit or suspend the emission of
air at pleasure. The air chamber is always kept charged with condensed air
in readiness for use; it is therefore simply necessary that the guard or other
person in charge should open the communication between the reservoir and
the main tube, when an instantaneous audible signal will be produced by the
whistle at the opposite end. A code of conventional signals may be arranged
by making the sounds of more or less duration, or by the combination of long
or short durations of sound.
Fig. 1, Sheet A, represents a train of carriages fitted with my improved
apparatus of communication between the break or guards van A, and the
engine driver. Fig. 2, a longitudinal vertical section of the guards van, in
which the receiver for containing the compressed air is placed, as also appa-
ratus for compressing and maintaining the pressure of the air in the receiver
during the action of the apparatus. Fig. 3 represents a transverse vertical
section of the break van and compressed air apparatus. B is a strong receiver
of boiler plate or other suitable material of any convenient shape.
It is repre-
sented here as a high flat vessel for the convenience of fitting the other parts
thereto, and for occupying little room, in which form it must be properly stayed
to render it capable of sustaining great internal pressure.
C is an air pump
fixed on the receiver B, which pump receives motion from the axle D of the
carriage through intermediate geering, and forces air into the air chamber B
during the continuance of its motion. For the purpose of actuating the

page_text: pump C, a strap pulley E is fixed on the axle D, or to the side of the wheel,
whose rotatory motion is transmitted by a strap or band F to the strap rigger
G, which is mounted on a stud axle a. In order that the vibratory motion or
difference of level in the carriage body may not interrupt the action of the
strap F, I form it of a greater length than is required to encircle the riggers;
and for the purpose of producing the driving contact I cause it to be deflected
from the straight line by a tightening pulley b, which is kept up against it by
means of a helical spring c. The pulley, is mounted on the lower end of a
lever H, which lever moves on a fixed fulcrum at d, and the spring c being
attached at the one end to this lever, and the other to a stud e, fixed in the
receiver, the spring applies a constant force to keep the lever H in the position
shown, and thereby maintains a constant tension on strap F. This tightening
lever and pulley enables the guard to suspend the operation of the machine.
This is effected by drawing over the upper end of lever H to the position
shown dotted, when it falls into a notch f, cut in a guard piece g. The face
of the guard piece causes the lever to spring off as it is pulled over, so that
when it springs back into notch f, it remains in the dotted position until
released by hand. The effect of this motion of lever H allows the strap F to
hang loose round the lower pulley, and so suspend the motion of the air
apparatus. h is a broad flange to prevent the strap getting off the pulley E
when it is slackened by the pulley b. On the boss of wheel G a pinion i is
fixed, which pinion geers into the toothed wheel I, also mounted on a stud
axle j, passing through chamber B, which together with a form stays in that
chamber. The rapid motion of the axle D is thus reduced by the geering, and
communicates a motion of about thirty revolutions per minute to wheel I. In
the arm of wheel I a stud is fixed, which is connected with the slings of the
pump, and forms a crank by which a reciprocating motion is transmitted to
the piston of the pump. The pump C, which is shown in section, is similar
to an ordinary air pump inverted, being open at the lower part where it draws
in the air; passages are made through the piston through which the air passes
in the downward stroke, but prevented returning by oiled silk or other valves
placed on the upper surface of piston, which close these passages during the up
stroke. Similar passages and valves exist in the top plate 7, which permits
the air to pass into the dome top m, but prevents its return. It is conveyed
thence by pipe n into the receiver, and retained there under pressure. Lis
a safety valve, which is loaded according to the pressure required to work,
say, fifty pounds on the square inch. Thus, although the pump continues to
work, the excess of air beyond the proper pressure is allowed to pass off by the
safety valve; it will, however, be useless to keep the apparatus in action when

page_text: the whistle is not in requisition. I therefore prefer that it be thrown out
of geer, as described, by the hand lever II, after the requisite compression
of air has been obtained. The lever is again released, when the signal is
to be used. p is a pressure guage, to indicate to the guard the pressure of
air contained in the receiver. K, K, is the main pipe of communication
with which each carriage of a train is fitted. It is suspended a little below
the framework of the carriage by pendants 9, 9, and is furnished at either end
with a conical nosce piece, seen separately in Figs. 4, 5, & 6, Sheet B. r, r, are
set nuts for fixing the putting at one or both ends. The conical nose is fitted
with a socket M, and secured thereto by a bayonet joint, and having a handle s
for the ready application or removal of the socket; a swivel piece t is fitted to
the socket, to which piece a strong piece of vulcanized india-rubber or other
flexible air-tight piping X is secured, at the opposite end of which flexible
piping a similar socket is secured, whereby it is also united to the pipe K of the
next carriage, as seen in the carriages of the train, Fig. 1. The slot u of the
socket M, as will be seen in the plan, Fig. 5, is inclined in its direction round
the circumference, so that on turning the socket round for securing it the
effect of its action on the pin v, which is fixed in the nose piece w, is to draw
it further on the cone; it at the same time forces the swivel piece hard up
against the nose of w, and a leather or other washer being interposed between
the two an air-tight joint is ensured. An opposite circumferential motion has
the effect of loosening, and so disengaging the parts. In this way the whole
length of a train may readily have the air pipes K, K, connected.
ม
The india-rubber junction being loose, hangs below the drag links and
chains, and it is quite impossible to get out of order, as it is capable of any
distension to which it would be subject without injury occurring, and is very
slight additional trouble to connect when the trade is made up. N is the pipe
connecting the main pipe K with the air receiver B, which pipe has a stop-
cock x placed in a convenient position to the guard while at his break handle P.
is another stop-cock to a whistle R which the guard sounds if he wishes to
signal any coming train behind, or it may be if the pressure of air in the
receiver is sufficient that he may signal the engine driver of his own train
therewith without the intervention of the communicating pipe K. S is the
signal whistle to be sounded by the air passing through pipe K; this whistle
is placed on the tender, as shown, or in other convenient position where it will
be readily heard by the driver. The pipe K on the tender leads to this
whistle, and is connected to the first carriage of the train in the same way
as the other junctions. Thus when the guard desires to signal the engine
driver of his train, he has simply to open the stop a short time while

page_text: the engine driver may make counter signals with the steam whistle in the
usual way.
In order to close the back end of pipe K, a blind socket T is fitted to each
nozzle w, such as shown at Fig. 7, which effectually closes the back end of
pipe and prevents the escape of air in that direction. These blind sockets are
fitted and remain on blank nose pieces placed at each end of the carriages in
readiness for use in breaking or making up a train. Fig. 6 represents an end
view of a socket placed somewhat in the position they should occupy when
applied, that is, with the weight of the handles having a tendency to bind
them on tighter. z represents dotted a handle, which may be introduced in
a boss provided for the purpose, whereby the wheel G may be driven by
hand to pump air in the event of the strap giving way. Instead of driving
the pump by means of the rotary motion of the wheel of the carriage, an
ordinary hand pump may be fitted and applied for the purpose of compressing
the air.
Figs. 8 and 9 represent another arrangement of apparatus for actuating
the pump and pumping air into the receiver, Fig. 8 representing a front
elevation, and Fig. 9 a side view thereof. It consists of an eccentric 1, placed
on the axle of the carriage which at each revolution acts as a cam on the tail
of the lever 2, which is mounted on a fixed fulcrum at 3; a pall 4 is fitted
to the upper part of lever 2, which takes into the ratchet wheel 5, which
supplies the place of the wheel I. In the last-mentioned apparatus the
receiver B, pump C, and slings, with its crank connection, is the same as before,
together with the valves and necessary gauges; a spring 6 constantly draws
the upper part of the lever to the left, and consequently keeps the lower or
tail end always up against the cam 1. The action of the apparatus is this:-
The cam 1 each time it comes round causes the lever to be oscillated, cach
oscillation moving the pall a distance of two teeth in the one direction; the
pall slips over the teeth in the opposite direction; the pall 4 forces the
ratchet wheel round a distance of two teeth, successive actions causing entire
revolutions of that wheel in the direction of the arrow. The revolutions of the
carriage axle being necessarily very quick, these oscillatory movements will be
repeated very rapidly, and an almost continuous motion of the ratchet wheel,
and consequently of the pump, will ensue. A more continuous action might
be induced by the application of a small fly wheel on the axis of the ratchet
wheel.
When it is desired to suspend the operation of this apparatus, it is simply
necessary to throw back the pall 4, so as to be out of geer with the ratchet
Other methods of working the air pump may be devised, as for
'wheel 5.

page_text: instance, by means of an eccentric on the carriage axle, whose strap has direct
communication with the pump or with a crank similarly fitted; but I believe
that the methods shown will be found the best for the purpose.
In witness whereof, I, the said Thomas Thurlby, have hereunto set my
hand and seal, this Twenty-seventh day of July, in the year of our
Lord One thousand eight hundred and fifty-four.
Witness,
W. CLARK,
Patent Agent,
53, Chancery Lane,
London.
THOMAS THURLBY. (L.S.)