Improvements in Mechanical Signal Apparatus for the Protection of Trains Standing at Fixed Points or whilst Passing Through a Given Section.
Year: 1894

page_text: Date of Application, 1st Feb., 1894
Complete Specification Left, 1st Nov., 1894-Accepted, 1st Dec., 1894
PROVISIONAL SPECIFICATION.
Improvements in Mechanical Signal Apparatus for the Protection of
Trains Standing at Fixed Points or whilst Passing Through a
Given Section.
CHARLES BROWN 21 Chesilton Road, Fulham, London, S.W., Engineer, do
hereby declare the nature of this invention to be as follows:-
For this purpose I place in the run of the home signal connection and between
the signal lever and the signal a mechanical device for disconnecting or breaking
the continuity of the said connection this mechanical device is operated by a treadle
which is depressed by the first wheel of the train the before mentioned signal
connection is continued from the above mentioned mechanical device to one or
more protection bars so placed that some of the wheels of the train shall be upon
the bar or bars whenever the said train shall be standing at the station or other
fixed point the signal connection is continued from the protection bar to the home
signal near the home signal and between the home signal wire and the distant
signal wire I introduce a double wheel slot this allows the home & distant signals
to go to danger at the same time but prevents the distant signal being lowered
until after the home signal I also provide special interlocking between the home
and starting. signal levers which will prevent the home signal being lowered a
second time unless the starting signal has been lowered and again put back to
danger.
It will be seen from the foregoing that in the case of a train coming into a
station or other fixed point the home and distant signals are lowered in the usual
manner whilst at the same time the treadle of the mechanical device for discon-
necting is raised and the train protection bar is also raised when the first wheel of
the train reaches the treadle the disconnector is actuated the protection bar passes
down out of the way and both the home and distant signals go to danger behind
the train thus protecting it independent of any movement of the signal levers by
the signalman should the signalman endeavour to admit a second train he is unable
to do so because in the first place the train protection bar cannot rise on account
of the wheels of the first train being upon it and as the bar forms part of the
signal connection its rise is essential to the lowering of the signal and in the second
place the special interlocking between the starting signal lever and the home signal
lever prevents the home signal lever being pulled over a second time until the
starting signal lever has been pulled over and again put back.
1004

page_text: COMPLETE SPECIFICATION.
Improvements in Mechanical Signal Apparatus for the Protection of
Trains Standing at Fixed Points or whilst Passing Through a
Given Section.
I, CHARLES BROWN, of 21 Chesilton Road, Fulham in the County of Middlesex,
Engineer, do hereby declare the nature of this invention and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement :-
My invention is intended to obtain two results, firstly, that after the home signal
bas been lowered to allow a train into a station or to allow a train into any given
point, as long as that train is standing fouling the line the home signal cannot be
lowered a second time to admit a second train as long as the first is fouling
the line.
Although I have referred to a home signal yet it is obvious that my invention
effecting this result might be applicable to any signal.
The second point consists in automatically putting the signal to " Danger" on
the passage of the train. For this purpose I place in the run of the home or other
signal connections, between the signal lever and the signal, a mechanical disengaging
apparatus, which is operated by a treadle. On the first wheel of a train passing
over the said treadle the disengaging apparatus is operated and the signal or
signals are thrown to "Danger." A distant signal is shown on the drawing
annexed.
Beyond the disengaging apparatus and parallel to the rail, is or are one or more
fouling bars according to the amount of rail required to be protected. The fouling
bars are connected to the disengaging apparatus and from the further end of the
last fouling bar the rod and wire connection is taken back to a draft wheel or
sliding pulley, round a fixed pulley and back to the lever of the home or other
signal
as is desirable. The draft wheel or pulley in the return of the home signal
wire connection is connected to the home signal and a junction in the wire is made
round another draft wheel back to the distant signal lever; a wire fixed to the bed-
plate that carries this draft wheel is carried round a second draft wheel to the
distant signal.
In order that my invention may be better understood and more readily carried
into effect I will proceed to describe the drawings hereunto annexed.
Figure 1 is a plan showing my apparatus; the draft wheels are shown in plan
for the purposes of illustrating it, these wheels are actually fixed in elevation as
will be seen in Figures 6 to 9 inclusive.
Figure 2 is an enlarged side view of the disengaging apparatus in the normal
position, that is to say, before the home signal lever has been operated the treadle
is out of engagement with the wheels of a passing train.
Figure 3 is a plan of Figure 2.
Figure 4 is similar to Figure 2, but shows the position of the apparatus after the
home signal lever has been operated; by this action the treadle is brought into
position ready for engagement with the wheels.
Figure 5 is a view of Figure 4 after the treadle has been depressed by the wheel
and the disengagement has taken place.
Figure 6 is an elevation of the wheels or slots connected to the distant signal
lever in the one case and the distant signal in the other case. In this figure the
wheels are in the normal position.
Figure 7 is a view of Figure 6 after the wheels have been operated by the
levers.
Figure 8 is an elevation of the draft wheel or slot in the return of the home
signal wire with the wheel and chain in the normal position.
Figure 9 is a view of Figure 8 after the home signal lever has been operated.

page_text: The same numbers refer to the same parts in the several figures of the
drawing:
1 is the home signal lever in plan, 2, 2, the rod connections to the disengaging
apparatus, 3 is the disengaging apparatus, 4 is an arm attached to the rocking
shaft 5, 6 is the treadle, 7 the rod connections from the disengaging apparatus to a
rocking shaft 8, in lieu of a rocking shaft au ordinary horizontal crank can be used,.
9 is the rod attachment from the rocking shaft to the fouling bar 10, 11 is the rod
attachment from the said bar, 12 the return wire connection from the bar to the
draft wheel or slot 13 14 is a fixed wheel, 15 is a fixed wheel near the lever,.
16 is the point of junction of the wires from the slot of the draft wheel 13 the one
wire 17 going to the home signal and the other wire 18 going to the distant signal
lever. 19 is the distant signal lever, 20 the first wheel from the distant signal
lever, 21 is the first draft wheel operated by the wire from the junction 16 to the
distant signal lever 19. 22 is the draft wheel around which the wire 23 operates,
one end of the latter is fastened to the base plate as shown in Fig. 6-the other
end goes to the distant signal 24. 25 is the home signal, 26 is the upper blade of
the disengaging apparatus, 27 is the back portion of the said blade, 28 is the pawl
on the said blade, 29 is the lower blade of the disengaging apparatus, 30 is the
bent portion corresponding to 27 in the upper blade, 31 is the projection on the
lower blade for engagement with the pawl 28 of the upper blade. 32, 33, 34, 35 are
guides for the disengaging apparatus.
The action of my invention is as follows:-
When the signal lever 1 is operated the rods 2 and the upper blade 26 of the
disengaging apparatus is operated the pawl 28 of the said blade engages with the
projection 31 of the lower blade 29 of the disengaging apparatus moving the said
lower blade towards the lever. The arm 4 attached to the rocking shaft 5 to which
the treadle 6 is connected is lowered by the action of the upper and lower blades
when the lever 1 is operated, this actuates the rocking shaft 5 and raises the
treadle 6 above rail level ready for engagement by the first wheel of the next train
over it. The bar 10 and the connections 11 and 12 are also moved as is also the
draft wheel 13. The end of the wire connection 12 terminating with the lever
cannot be moved from that direction therefore the draft wheel 13 is moved
operating the wires 17 and 18, the latter being joined at 16 thus deflects the stop
signal and operating the draft wheel or slot 21 which is connected to the draft
wheel 22 takes up the slack wire to the distant signal 24. When the distant signal
lever 19 is operated the distant signal 24 would be deflected. Upon the passage
of a train over the treadle, shown in elevation Fig. 4, the said treadle is depressed,
the arm 4 operating on the top blade 26 of the disengaging apparatus raises the
pawl 28 out of engagement with the projection 31 on the lower blade 29, immediately
this is effected the balance weights and arms on the home signal 25 and distant
signal 24 are sufficient to force the arm to "Danger" and pull the lower blade into
position as shown in Fig. 5. The train now proceeding stops on the bar and the
home signal lever on being returned to the normal position the rods 2 force the
top blade 26 of the disengaging apparatus so that by gravity the pawl falls into
the position shown in Fig. 1 ready for engagement on the next operation of the
lever similar to that described in Fig. 4. If the signalman wishes to lower the stop
signal a second time while the train is standing on the bar 10 he cannot do so
because the bar 10 has to move as it forms a part of the connection to the home
and distant signals and if it cannot be moved the signals cannot be deflected.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I wish it to be understood
that I am aware that disengaging apparatus has been used before and that draft
wheels and slots of that nature have been used before, I, therefore, do not
separately claim any of these, but what I do claim is :-
1. In railway signalling, a disengaging apparatus and treadle operatively con-
nected so that the first wheel of a passing train replaces to the "Danger" attitude

page_text: any desired signal or signals, substantially as described and as illustrated in the
accompanying drawing.
2. In railway signalling apparatus, the combination of the treadle and dis-
engaging apparatus such as described and claimed in Claim 1 with the protection
bar, the whole operating that once the signal is replaced to the "Danger" attitude
it cannot be operated again as long as any obstruction is standing on the said bar,
all substantially as herein set forth and as illustrated in the accompanying
drawing.
3. In railway signalling, the combination of apparatus substantially as described
and illustrated and for the purposes herein set forth.
Dated this 1st day of November 1894.
JOHN P. O'DONNELL,
70 and 71, Palace Chambers, Bridge Street, Westminster, S.W.,
Agent for the said Applicant.