IMPROVEMENTS IN APPARATUS FOR INTERLOCKING RAILWAY POINTS to be as follows:
Year: 1884

page_text: I, JOHN STEVEN of Glasgow in the County of Lanark, Signal Superintendent, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN APPARATUS
FOR INTERLOCKING RAILWAY POINTS to be as follows:-
"
This Invention relates to improvements in apparatus for interlocking railway
points between stations on the train tablet system.
The apparatus constituting the Invention consists of a box or case wherein is
centred a lever one end of which is formed with an eye or hole the said end being
situated between the jaws of a bracket or crank made on a shaft or bar placed at
right-angles to the length of the lever. From the sides of the said jaws pins
project in the direction of the eye. The other end of the lever is acted on by a
spring and has a pin or arm projecting at right angles from it, which pin when the
train tablet is in the apparatus enters a recess made to receive it in the periphery
The tablet is enclosed in an inner case provided with a lid which can be prevented
from being raised by a lock consisting of a lever or bar connected at one end to a
crank on the transverse shaft before referred to. On the said shaft another crank
is made and connected to a vertical bar the edge of which has two notches or
recesses with a curved portion between them or is formed in an equivalent manner
to receive the point of a tumbler or bar which is so acted on by a spring as to be
forced into one or other of the said notches or recesses and so hold the bar in a
raised or lowered position. The lower end of the said vertical lock bar enters a
slot made in the bar connecting the apparatus to the points.
The action of the apparatus is as follows:-When the train tablet is inserted in
the case the notch in its periphery acting on the arm or pin connected to the lever
forces the lever (against the action of the spring) into such a position that the eye
on its forward end is intermediate between the two pins carried on the transverse
shaft which shaft can then be moved through an arc so as to raise the locking bar
free of the slot in the bar connecting to the points, the said motion at the same
time locking down the cover or lid of the case containing the tablet and so
preventing the removal of the tablet until the points are again closed or set for the
main line by turning the transverse shaft in the opposite direction. When the
tablet is not in the case the spring acting on the rear end of the lever forces
the eye on its forward end on to one of the pins carried by the transverse shaft,
whereby the said shaft is locked immovable until the tablet is again inserted.

page_text: I, JOHN STEVEN of Glasgow in the County of Lanark, Signal Superintendent,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
APPARATUS FOR INTERLOCKING RAILWAY POINTS" and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement:-
This invention relates to improvements in apparatus for interlocking railway
points between stations by means of what is known as a "train tablet."
On the sheet of drawings hereunto annexed figure 1, is a side elevation and
figure 2, a plan of the improved apparatus figure 3, being a vertical section on the
line a, b, figure 4, which is a horizontal section on the line c, d, figure 3.
As seen by these figures the improved apparatus consists of a box or case A, in
which, on a stool or support B, a lever C, is centred. One end of the lever C, has
an eye or hole made in it, the said end being situated in the space between two
cranks or arms D, made on a shaft or bar E, placed at right-angles to the length of
the lever C, and supported in bearings F, carried or formed on the sole of the
case A. From the inner sides of the cranks or arms D, pins e, el project towards
the eye in the lever C, as seen more particularly in plan at figure 2.
The other end of the said lever which is acted on by a spring f, has an arm or
bar g, so connected to it by a pin as to project at right angles to the lever as is also
seen at figure 2; and this bar when the train tablet h, is in the apparatus enters a
recess made in the periphery of the tablet to receive it.
The tablet h, is enclosed in an inner case i, formed on or secured to the stool B,
and provided with a lid or cover j, hinged at the back and at the front made with
a downwardly curved part working through an opening in the side of the case A,
as seen at G, figure 1. The said curved part which is provided with a lifting tag
or finger piece k, completely covers or encloses (when in its lowered position) the
entrance to the tablet case i.
To prevent the lid or cover j, from being raised except at the desired times a
lock is employed consisting of a bar l, connected at one end to a crank m, on the
transverse shaft E, On the said shaft another crank n, is made or secured and
connected by a pin o, to a vertical bar H, passing through a guide bracket I, and
through a slot in the bottom of the casing A, On one side or face of the bar H,
two notches or recesses with a convex portion between them are made as seen at x,
figure 3, to receive the point or end of a bolt or bar p, carried in a bracket 2, and
acted on by a spiral or other spring so as to force it into one or other of the said
recesses and so hold the bar H, in a raised or lowered position.
The lower end of the said vertical lock bar H, passes through a guide I¹, and
through a slot made in a bar J, connecting the apparatus to the point rod J¹, and
acts to lock the said rod J¹, and through it the points themselves.

page_text: To prevent this interlocking apparatus being operated to open the points except
when a tablet has been placed in the case i, a bar s, is hinged or jointed at one end
to the cover j, opposite the end of the lock bar l, as seen at figure 2, and in detail
at figure 5. In the bar s, two pins t, are fixed these pins projecting through holes
in the lid or cover j, into the interior of the case i. When the case i, is empty, the
bar 8, is in the position shown in full lines at figure 5, that is to say, it abuts
against the end of the lock bar or bolt l, and prevents it from being shot forward
over the lid or cover j, but when a tablet is inserted in the case i, the said tablet
acting on the pins t, forces the bar 8, upwards into the position shown in dotted
lines figure 5, in which position the end of it is above the end of the bar or bolt 1,
which can then be shot forward over the lid j, so as to lock it down.
When the train tablet h, is inserted in the case i, the notch herein before referred
to in its periphery acting on the arm or bar g, connected to the lever C, forces the
lever (against the action of the spring f) into the position shown at figure 2, that is
to say into a position in which the eye or hole in the end of the lever is intermediate
between the two pins e, e¹, and is free from both. The shaft E, is thereby rendered
capable of being turned through an arc so as to raise the locking bar H, out of the
slot in the bar J, connecting to the point rod J¹, the said motion at the same time
locking down the cover or lid j, of the case i, through the intervention of the bolt 1,
and crank m, as berein before described. The points may then be opened or set for
the branch line the bar l, preventing removal of the tablet h, until the points are
again closed or set for the main line which being done the shaft E, in being turned
in the reverse direction, so as to withdraw the bolt I, and enable the tablet to be
removed, lowers the locking bar H, through the slot in the bar J, whereby the
points are interlocked.
An indicator is or may be provided in conjunction with the shaft E, as at M,
figure 1, to show the position of the points.
When the tablet h, is not in the case i, the spring f, acting on the rear end of the
lever C, forces the eye in its other end on to or over the pin e, thereby rendering
the shaft E, immovable until the tablet is again inserted.
The train tablets are preferably made of different sizes for the different sections
of the line and to prevent the tablet for one section being used in the interlocking
apparatus of another section the pin e¹, is provided and in the event of an attempt
being made to insert a tablet larger in size than the one proper for the apparatus
the notch in the periphery of the said tablet acting on the arm g, of the lever C,
throws the eye in the other end of the lever on to the pin e¹, thereby locking the
shaft E, and preventing the points from being opened.
As a further preventative against improper use of the tablets h, each of them
may as seen at y, figure 6, have a hole made in it into or through which when the
tablet is in the case i, a pin projecting upwards from the bottom of the case i,
passes By varying the position of the said pins and by also varying the position
of the holes in the tablet as indicated in dotted lines at figure 6, no tablet other
than the proper one can be inserted in the apparatus.
Besides the spring f, herein before referred to an additional and spiral spring may
be connected to the lever C, and to the bearing E, or other fixed part of the
apparatus as indicated in dotted lines at f¹, figure 2, for the purpose set forth.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
First The arrangement and combination of parts constituting the improved
apparatus for interlocking railway points as described with reference to the
drawings annexed.
Second-The combination of the tablet h, lever G, and shaft E, with pins e, e', as
described and shown on the appended drawings.
Third The combination of the shaft E, crank m, bars l, and s, as and for the
purpose set forth with reference to the accompanying drawings.

page_text: Fourth-The combination of the shaft E, crank n, and bars H, and J, as and for
the purpose described with reference to the annexed drawings.
Fifth-The use of a train tablet in apparatus for interlocking railway points.