IMPROVEMENTS IN THE MODE OP WORKING JUNCTION SIGNALS ON RAILWAYS."
Year: 1860

page_text: LETTERS PATENT to Austin Chambers, of Bow, in the County of
Middlesex, Engineer, for the Invention of "IMPROVEMENTS IN THE MODE
OP WORKING JUNCTION SIGNALS ON RAILWAYS."
PROVISIONAL SPECIFICATION left by the said Austin Chambers at the
Office of the Commissioners of Patents, with his Petition, on the
5th January 1860.
I, AUSTIN CHAMBERS, of Bow, in the County of Middlesex, Engineer, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN THE
MODE OF WORKING JUNCTION SIGNALS ON RAILWAYS," to be as follows:-
The object of this Invention is to prevent the possibility of contradictory
signals being simultaneously given at the points of junction on railways, or a
safety signal being shewn when the "points" are not in corresponding
position.
For this purpose I make use of any suitable arrangement of stops or checks
connected with the levers, whereby the "points" made use of for turning trains
out of the main line into a branch, or vice versa, are moved. These stops are
so arranged that when the points are set for trains running on the main line,
to continue thereon past the point at which another or branch line enters it,

page_text: the signals referring to communication with the branch line will of necessity
stand in the position indicating "danger," and (by reason of the stops) cannot
even commence being moved from that position until the contrary or main line
signals have first been caused to assume the "danger" position, after which
the points may be moved so as to place the branch in communication with the
main line, and the act of moving them (the points) will cause the main line
signals to become locked and to remain immovably fixed, indicating "danger,"
until the contrary signal has been placed again in the danger" position, in
which it will be locked as before by the act of moving the points back to their
original position. The act of moving the points invariably locks the one signal
or set of signals in the "danger" position, and leaves the contrary signals at
liberty either to be placed in the position indicative of safety or to continue in
the "danger" position. Thus it will be understood that when desired (as
required in "shunting ") the whole of the signals may be kept at ". danger."
The same system is applicable also to the distance signals to prevent their
being shewn in the safety position when trains are about to cross over one of
the lines.
It is obvious that the system of stops or checks acting as described to
prevent the use of contradictory or inccorrect safety signals may be carried into
effect by numerous different mechanical arrangements, the construction of
which may be suited to the peculiar requirements of the particular situations
in which they are applied.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Austin Chambers in the Great Seal Patent Office on the
5th July 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, AUSTIN
CHAMBERS, of Bow, in the County of Middlesex, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of January, in the year of our
Lord One thousand eight hundred and sixty, in the twenty-third year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Austin Chambers, Her special licence that I, the said Austin'
Chambers, my executors, administrators, and assigns, or such others as I, the
said Austin Chambers, my exccutors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all times

page_text: 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 MODE OF WORKING JUNCTION SIGNALS ON RAILWAYS," upon
the condition (amongst others) that I, the said Austin Chambers, my
executors or administrators, by an instrument in writing under my, or their,
or one of their hands and seals, 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.
NOW KNOW YE, that I, the said Austin Chambers, do hereby declare tho
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement
.
The object of this Invention is to prevent the possibility of contradictory
signals being simultaneously given at the points of junction on railways,
or a safety signal being shewn when the points aro not in corresponding
position.
For this purpose I make use of any suitable arrangement of stops or checks
connected with the levers, whereby the points made use of for turning trains.
out of the main line into a branch, or vice versa, are moved. These stops are
so arranged that when the points are set for trains running on the main line, to-
continue thereon past the point at which another or branch line enters it. The
signals referring to communication with the branch lino will of necessity stand:
in the position indicating "danger," and (by reason of the stops) cannot even
commence being moved from that position until the contrary or main line
signals have first been caused to assume the "danger" position, after which
the points may be moved; and the act of moving them (the points) will cause
the main line signals to become locked and to remain immovably fixed,
indicating "danger," until the contrary signal has been placed again in the
danger position, in which it will be locked as before by the act of moving the
points back to their original position; the act of moving the points invariably
locking the one signal or set of signals in the "danger" position, and leaving
the other signal or set of signals at liberty either to be placed in the position
indicative of safety, or to continue in the danger position. Thus it will be
understood that when necessary (as in shunting) the whole of the signals may
be kept at danger."

page_text: DESCRIPTION OF THE DRAWINUD.
Fig. 1 of the accompanying Sheet of Drawings represents a back elevation
of an arrangement of my Invention applied to a main line, consisting of an up
and a down line of road or way, with a branch line of two similar roads or ways
entering it (as represented by the Diagram Fig. 4); Fig. 2 is an end elevation;
and Fig. 3, a plan, partly in section, of the same.
a represents the framing of the apparatus, having bearings at 6, carrying the
two shafts c and d, upon which are keyed the point levers e and f. The ends
of these levers are prolonged beneath their respective shafts, that of e being
connected by a joint at g to the upper stopping plate h, formed with projecting
parts working through mortices in the base of the frame a, and that off being
similarly connected by a joint at i to the lower stopping plate j, situated partly
beneath the former, and having projecting parts working through the frame in
a similar manner. In order more clearly to distinguish between the two plates
they are ruled with lines, those of the upper plate running at right angles to
those of the lower. Upon the shafts c, d, are also keyed the levers k and 1,
the former of which, like the lever e, is jointed at a corresponding distance
below the centre of the shaft c to the upper stopping plate h, the lever / being
in like manner (and at a distance beneath the shaft d corresponding with that
of the joint i of the lever f) jointed to the lower plate j. The rods m, n,
jointed to the lower extremities of the point levers e, f, are connected at their
opposite ends to the respective points, whereby the direction of trains at the
junction is regulated. o, p, q, r, are stirrups, each formed with an upper and
lower stalk or guide rod passing through corresponding guide holes formed in
the framing a. To the upper stalk or guide rod of each stirrup is attached a
chain s passing over a guide pulley t, from whence it is led in any required
direction, and connected at its opposite end with the signal arm. u represents
a pin projecting from the side of each stirrup, and travelling in a guide groove
formed in the framing a. This groove has a return or notch at v, into which
by a slight twist of the foot when the stirrup has been drawn down, the pin
can be caused to enter, and thereby.to prevent the ascent of the stirrup until
the foot has again released the pin from the notch.
In explaining the action of the apparatus, I will suppose that the stirrup o is
connected to the signal having reference to the line marked No. 1 on Fig. 4;

page_text: the stirrup p to the signal referring to line No. 2, the stirrup q to that of line
No. 3, and the stirrup r to that of No. 4. Now, on reference to Fig. 4, it will
be seen that in order to avoid the chance of collision from incorrect signals it
will be necessary that the following conditions be adhered to, viz. :-When the
line No. 1 is open and signalled safe accordingly, the line No. 3 must be sig-
nalled as closed, or in other words, trains running thereon must be stopped ero
passing the junction, by the danger signal. When line No. 2 is open, Nos. 3
and 4 must be signalled "danger." When No. 3 is open, the signals must
shew Nos. 1 and 2 closed; and when No. 4 is open they must in like manner
indicate that No. 2 is closed. In the position of the apparatus represented in
Figs. 1, 2, and 3, the lines Nos. 1 and 4 of the Diagram (Fig. 4) are supposed
to be open, and Nos. 2 and 3 consequently closed and requiring the danger
signal. Premising that the act of pressing down a stirrup into the position of
o or r has the effect of placing its corresponding signal at the "safety" or
"all right" position, and that when the stirrups are up, as in the cases of p
and 9,
the corresponding signals indicate danger, it will be easy to understand
the action of the apparatus, and the manner in which the stopping plates h and
jeffectually prevent a safety signal being shewn at an improper time. It will
be seen that in the position represented, the stopping plate h has, by the act of
setting the points for No. 1 line, been drawn back from beneath the lower
guide of the stirrup o, thus allowing that stirrup to be pressed down and the
corresponding signal to be thereby placed in the safety position; the act of
setting the points for No. 4 line having in like manner brought a hole through
the plate directly under the lower guide of the stirrup r, thereby allowing it
to be pressed down for the purpose of signalling the No. 4 line open; the
remaining stirrups p and q connected with the signals of Nos. 2 and 3 lines
being respectively kept up in the danger position by projecting portions of the
plates and h. It will also be seen that while the stirrups o and r remain
down, i.c., in the safety position, no movement of the point levers e and ƒ can
take place, inasmuch as the stopping plate h connected with the point lever e
is prevented from being moved forward by the lower guide of the stirrup o,
while the stopping plate j is in like manner prevented from being drawn back
by the lower guide of the stirrup r passing through a hole formed in the plate.
Hence it is necessary to release and allow the stirrups o and r to be drawn up
and to signal danger for the corresponding lines (Nos. 1 and 4) before the
respective points can be moved from their present position. When the points
have been moved, the stopping plates will be in a corresponding position to
allow the drawing down of the correct safety signals, and to keep the remaining

page_text: ones up at danger. By extending the stopping plates of the station signal
apparatus backward, as shewn in red lines, they may be made at the same
time to prevent the drawing down of the distance signals at improper times.
Thus for the junction shewn (Fig. 4), three distance signals would be required,
one of which, No. 5, might, under ordinary circumstances, always shew the
road open, but the other two, Nos. 6 and 7, must never be in the safety position
together. The levers w and a (shewn in red lines), whereby those signals are
worked, are consequently provided with segmental arms y and z, the end of one
of which resting upon one or other of the stopping plates according to their
position, prevents either of the signals from being shewn in the safety or "all
right position at an improper time. When it is safe or proper for either of
the distant signals to be at "all right," the plates will be in such a position as
to allow one or other of the segmental arms y, z, to pass through or beyond
.them.
Fig. 5 shews an end view of an arrangement, in which the signals, instead
of being worked by stirrups, as in the foregoing modification, are drawn down
by a hand lever o having its fulcrum at p, and carrying a pin 9, which acts
with the stopping plate (jointed to the point lever e) in the same manner as
the lower guides of the stirrups act with the stopping plates in the preceding
modification.
.
Fig. 6 represents an end view of another modification of my Invention, in
which the signals are worked by a hand lever o, having its fulcrum at p. The
drawing down of this lever is regulated by a pin or projection q, which rests
upon the edge or stopping can h attached to the point lever e, and which
either keeps the lever o up in its present position or allows it to be pulled down,
according as the position of the points for the time being requires.
In the foregoing description I have fully described and ascertained the
nature of my said Invention, and explained several of the methods whereby
the same may be advantageously carried into effect. It is nevertheless evi-
dently susceptible of various other modifications to meet the requirements of
particular cases, and which will readily suggest themselves to the practical
engineer. Without confining myself therefore to the precise details or arrange-
ments represented, I claim,-
Firstly, the use or employment of stops, moved, as required, by the levers
employed for setting the points for the purpose of preventing the shewing of
contradictory signals or of safety signals when the points are not in cor-
responding position.
Secondly, causing the placing of a signal in the "safety" or "all right"

page_text: position to lock the points, to which it has reference in the corresponding
position, and to keep them so locked until the signal has been moved again to.
the "danger" position.
Thirdly, the use of stopping plates or equivalents for the purposes described.
Fourthly, the use of cams attached to or connected with the point levers for
the purposes described.
Fifthly, the combination generally of the parts constituting the signal regu-
lating apparatus before described.
In witness whereof, I, the said Austin Chambers, have hereto set
my hand and seal, this Fifth day of July, in the year of our Lord
One thousand eight hundred and sixty.
AUSTIN (L.B.) CHAMBERS.
Witness,
FRANCIS WISE, Patent Agent,
Chandos Chambers,
Buckingham S., Adelphi, W.C.