IMPROVEMENTS IN INTERLOCKING LEVERS IN RAILWAY POINT AND SIGNAL APPARATUS
Year: 1886

page_text: I, JOHN PATRICK O'DONNELL of 6 Hythe Villas, Limes Road West Croydon,
in the County of Surrey, Signal Engineer do hereby declare the nature of my
invention for IMPROVEMENTS IN INTERLOCKING LEVERS IN RAILWAY POINT AND
SIGNAL APPARATUS to be as follows:-
My invention consists in improvements in the interlocking of Railway points
with their respective signals, and of Railway points with each other; whereby
any pair or more points that are, or may become, facing points for any traffic
movement, after having once been worked over, cannot be replaced to its or their
normal position or positions, or reversed during the performance of a traffic move-
ment; until each and all of the trailing points, which has and have been worked
over for such traffic movement has and have been replaced to its and their normal
position and positions.
According to my invention, I furnish each lever working the facing and trailing
points with a tappet or tappets which tappet or tappets has or have either a rib or
tooth or both on its or their underneath or uppermost or both sides.
These tappets are actuated by the levers to which they are connected, and work
sliding locks, which locks are carried by a bar, thro' which the tappets slide.
The locks engage notches in, and with the teeth and ribs of the said tappets, and
effect the novel mode of interlocking berein described.
The action of my apparatus is as follows-
It is of course necessary, and is usually effected by ordinary interlocking, that
the levers, working the crossing or other points, should release or be worked over,
before the signal for a traffic movement through them can be lowered to the "all
right" position. Now although my apparatus admits of perfect freedom between
facing and trailing point levers themselves when in their normal position that is
that neither one of them unlocks the other, yet when the signal for a traffic move-
ment through them, has been given, each and all of the trailing points as before
described is, and are bound to be replaced to its and their normal position and
positions before the facing points are free to be moved back or reversed.
Although I have herein before described the nature of my apparatus with
reference only to lines of Railway where independent signals are provided, autho-
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page_text: rizing traffic movements through facing and trailing points, yet I wish it to be
distinctly understood that I do not bind myself to that or any other application
of my apparatus, because it will be readily seen, that it may and will become
necessary in certain circumstances to control the movements of levers other than
those working points and signals in the manner effected by my apparatus-
Therefore The essence of my invention consists in ensuring a special rotation of
working levers when in their normal position, with a perfect freedom of replacing
them to that position in any rotation whatever, and of ensuring a perfect freedom
of working levers in any rotation whatever, when in their normal position with
the obligation of replacing them to that position in a given and certain rotation.
Dated this 1st day of March 1886.
COMPLETE SPECIFICATION.
Improvements in Interlocking Levers in Railway Point and
Signal Apparatus.
I, JOHN PATRICK O'DONNELL of 6 Hythe Villas Limes Road, West Croydon
in the County of Surrey Signal Engineer do hereby declare the nature of my
invention for IMPROVEMENTS IN INTERLOCKING LEVERS IN RAILWAY POINT AND
SIGNAL APPARATUS and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:-
My invention consists in improvements in the interlocking of Railway points
with their respective signals, and of Railway points with each other, whereby any
pair or more points, that are, or may become facing points for any traffic movement,
after having once been worked over, cannot be replaced to its or their normal
position or positions, or reversed, during the performance of a traffic movement
until each and all of the trailing points which has and have been worked over for
such movement, has and have been replaced to its and their normal position
and positions. Although this description of the nature of my invention, refers to
facing points that have been, or are required to be moved over or worked, before
authority is given for a traffic movement through them; yet my invention also
relates to facing points that do not require to be moved over or reversed, that is
those points that lie normally right for the particular traffic movement, and in
those cases my invention prevents the facing points from being moved over or
reversed until the trailing points in connection with such traffic movement have
been reversed, or placed to their normal position, or in the event of the trailing
points also lying normally right then the lever or levers working such trailing
points must be moved slightly forward on the segment, or the catch handle raised
before the facing points are free to be moved.

page_text: According to my invention I furnish each lever, working the facing and trailing
points with a tappet or tappets, which tappet or tappets has or have either a rib or
tooth, or both on its or their underneath or uppermost or both sides.
It will be obvious that in carrying out my invention I shall have sometimes to
connect the before mentioned tappet or tappets direct to the body of the lever or
levers and again at other times I shall have to communicate motion to the tappet
or tappets through suitable connections by means of the catch handle, according to
the manufacture of the Locking Apparatus.
In order that my said invention may be most fully understood and readily
carried into effect, I will proceed to describe the Drawings hereunto annexed.
The parts shewn etched in figures 1. 2. 3 and 4 are intended to represent the
sectional plan of the levers in the Locking Apparatus which work the points,
signals &c.
Figure 1 is a plan viewed partly in section of the apparatus shewing one of the
methods by which I carry out my invention.
In this figure 1º is the tappet attached to lever 1 which lever actuates the signal
to the "all right" position in the direction which would make the points actuated
by lever 2, facing points.
2e is the tappet attached to lever 2 which works the said facing points.
4e is the tappet attached to lever 4 which lever actuates points that are trailing
for the direction to which the signal actuated by lever 1 applies.
5° is the tappet attached to lever 5 which lever actuates the signal in the opposite
direction to the signal actuated by lever 1.
The points actuated by lever 4 become facing points in the direction to which
the signal actuated by lever 5 applies.
The locks 1, 2, 4° are connected together by a narrow strip of metal on their
underneath side in the usual manner, and for the purposes of illustration let them
be called bottom locks.
The locks 2, 4, 5 are connected together in a similar manner, but the strip of
metal connecting them is on the uppermost side, therefore let them be called top
locks.
Sometimes I arrange these locks in the same channel but with the connecting
slides on the same level, and at other times I fix them in separate channels as
shewn in figures 2 and 3.
2 and 4° are the ribs, shewn by preference on the underneath side of the tappets
actuated by levers 2 and 4 working the points.
2° and 4° are the release notches in tappets actuated by the levers 2 and 4 working
the points.
It will be observed that the tappets actuated by the levers 1 and 5 working the
signals cannot be moved forward in consequence of the locks 1ª and 5 being
inserted in notches 1b and 5b in the said tappets.
Figure 2 is a plan viewed partly in section, and is simply another method of
effecting my invention by means of teeth Y and Z preferably fixed on the under-
neath side of the tappets worked by the levers actuating the points.
In connection with this figure it must be understood that levers 2 and 3 releasing
both levers 1 and 4 is effected by usual interlocking on any modern system as is
also lever 1 locking lever 4.
Substantially the last remark refers to all the figures.
Figure 3 is also a plan viewed partly in section, on the same principle as figure 1,
but coupled with tappets 2 and 3 in both of which there is cut a long slot, for
the purposes of allowing the signalman to feel by handling the levers 2 and 3
whether a train or engine is travelling over the points actuated by the said levers,
when the points are in the trailing direction.

page_text: Figure 4 is also a plan viewed partly in section, but which combines both the
rib and the tooth methods, and effects the same result as figures 1. 2 and 3 effect,
but under different conditions.
I will now describe the action of my apparatus as effected by figure 1.
To enable the lever 1 which actuates the signal to be moved over or worked,
lever 2 working the facing points in the direction to which the signal applies, must
be worked right over, and lever 4 working the trailing for the same traffic move-
ment must also be worked over, the result of their united action being that the
rib 2b on the underneath side of the tappet worked by lever 2 bas moved clear of
the lock 2, and the release notch 4 of the tappet worked by lever 4 has moved
sufficiently forward to be in the same straight line as the lock 4°.
Now lever 1 is free to be moved and let it be assumed that it is so moved.
The action of the tappet worked by this lever is such, that it forces the square
lock 2, behind the rib 2b on the underneath side of the tappet worked by lever 2,
and also forces the lock 4 into the release notch 4 on the tappet 4° worked by
lever 4.
"
As is both usual and right in conducting traffic movements, the signal lever 1
is moved back to its normal position, thereby throwing the signal arm to the
Danger" position.
It will now be seen that lever 2 working the facing points cannot be replaced to
its normal position or reversed during the performance of a traffic movement until
lever 4 (working the trailing points) has been first moved back or reversed, because
the lock is behind the rib 2b and there being no bevel on the rib the tappet
cannot communicate motion to the lock.
Lever 4 must therefore be reversed or placed at normal again, the result of this
action being that the release notch 4 of the tappet 40 worked by lever 4, forces
back to their normal positions the locks 1, 2 and 4 thereby freeing the backward
movement of the facing points lever 2 as the lock 2ª has moved clear of the rib 2b.
The action of my apparatus as represented by levers and tappets 2, 2, 4, 4c
and 5, 5° in the same figure 1 when the points worked by lever 4 are facing points
is simply a repitition of the above description.
The action of my apparatus as shewn in figure 2 is similar to the action of
figure 1 with teeth substituted for ribs.
Ths action of my apparatus as shewn in figure 3 is also similar to figure 1 except
that the signal lever or levers is or are free, before the respective trailing point
lever or levers, has or have completed its or their movement or movements on the
segment or segments.
The action of my apparatus as represented in figure 4 is a combination of the
rib and tooth methods, that is a rib on one point lever and a tooth on the other.
In this case it is simply necessary that one point lever should be worked over
before the signal for a traffic movement is free, as it will be readily understood,
that although it is sometimes necessary to work over the facing points, yet the
trailing points may lie normally right and therefore should not be moved for such
traffic movement.
In such cases I prevent the facing points from being reversed until the lever
working the trailing points has been moved slightly forward, that action freeing
the backward or reversing motion of the lever working the facing points.
This figure 4 also shews the action of my apparatus when the facing points
themselves lie normally right, and when the trailing points only are moved over,
and my invention also provides against the reversing of facing points when both
the facing and trailing points lie normally right, that is when neither of them
require to be worked for the performance of a traffic movement.
ベー
Although I have hereinbefore described the action of my apparatus with reference
only to Lines of Railway where independent signals are provided authorizing
traffic movements, through facing and trailing points, yet I wish it to be distinctly
understood, that I do not bind myself to that or any other application of my
apparatus because it will be readily seen, that it may and will become necessary in

page_text: certain circumstances, to control the movements of levers, other than those working
points and signals, in the manner effected by my apparatus, and in order that my
novel mode of interlocking (herein before referred to as my invention) may be most
clearly defined I will proceed to describe it in and by the following statement.-
The essential features of novelty in my invention consist on the one hand in
enforcing a special rotation of working levers when in their normal position, and
of allowing them perfect freedom to be replaced to that position in any rotation
whatever, and again on the other hand of allowing perfect freedom between lever
and lever when in their normal position, and of enforcing them to be replaced to
that position, in a special and given rotation.
On the accompanying Drawings I have shewn some examples of the way in
which I effect my invention.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I wish it to be
distinctly understood that I do not claim the system generally known as the
tappet system of interlocking, but what I do claim is-
The use of tappets for effecting the novel mode of interlocking substantially as
described.