Improvements in Working, Controlling, and Detecting Railway Signal Apparatus.
Year: 1888

page_text: Improvements in Working, Controlling, and Detecting Railway
Signal Apparatus.
We JOHN PATRICK O'DONNELL, of Penrith Road New Malden in the County of
Surrey, Civil Engineer and Patent Agent, and LEICESTER BRADNEY STEVENS of
Darlington Works, Southwark Bridge Road, in the said County of Surrey, Engineer
do hereby declare the nature of this invention to be as follows:-
Our invention has reference to improvements in working, controlling and detecting
safety apparatus in connection with the Facing Points of railways principally, but it
also has reference to signalling apparatus generally.
:
The first portion of our invention consists in improvements in the working and
detecting the actions of all bars, used in connection with signals, except those that
work in conjunction with the plungers at Facing Points of railways.
:
It is a frequent practice to provide bars beyond the switches at the fouling of two
or more lines of railway, to ensure that the tail of the train has cleared the conflicting
line, before a signal, through that conflicting line, can be given "all clear.". It is
also customary on certain lines of railway, to provide rear bars, (instead of duplicating
signals) where Facing Points are beyond the safe limit of distance, to ensure that
when the signal is replaced to "danger," the Facing Points cannot be reversed, until
the train has passed over them.
Again among other applications of bars, there is that 'application where they are
used to prevent points (cross-over roads, sidings fet.) which may be a considerable
distance from their respective. fouling signals from being opened or reversed, until
the train has passed over them.
In all applications therefore (with the exception of that above referred to) where
bars are used in connection with railway signals, it is highly essential that they should
have worked correctly before any correlated signal is given "all clear."
The object of this portion of the invention then, is to prevent the respective signals
from being lowered, indicating the line safe and clear, if any of the connections 'to
the said bars have given way, or if the bars have not gone correctly home, in both
positione
·

page_text: We effect this, in the following manner-Where it is allowable to work the bar
and the signal with one lever, we run the usual connection to the bar, and a separate
connection (rod or wire) from the bar to the signal.
Where however it is desirable to work the bar by one lever, and the signal by
another independent lever, we run the usual connections to the bar, and arrange a
separate connection from the bar, crossing the signal connections by means of suit-
ably notched blades, the whole operating, that normally the signals are locked at
danger, and that the signals are only released by the correct working of the bar,
through its separate detecting connection.
It may be found desirable, and preferred by some, to add an additional detecting
blade or like substitute from some part of the usual connections to the bar and arrange
it likewise to cross the signal connections, and operate in a similar manner to the
before referred to separate connection from the bar.
The bar will be counterbalanced to ensure its return to its normal position in the
event of fracture to any of its connections.
It may be found suitable to effect our invention by means of forming the detecting
blades into tappets and interlocking them on the tappet system of interlocking with
the signal connections.
It may also be found suitable to effect our invention by means of cranks of the
escapement kind, acting in such a manner that the correct working of both connections
of the bar are necessary before a single connection crossing the signal connections, is
operated to free the signals.
It is obvious that while expressing preference for the first described methods, we
yet include the other described methods as practically effecting our invention.
The second portion of our invention has for its object certain improvements in
detecting the actions of the switch points and of the facing point locks or plungers
at the facing points of railways. In consequence of the inconvenience arising out of
the present system of detecting points and plungers, through causing the wires from
the correlated signals to pass across or through blades from the said points and
plungers (as in Hancox's specification No. 5582 of 1884) or again through causing
the wires from the correlated signals to cross the lines of way at right angles to the
plunger and parallel to the stretcher bar (as in Kirby's specification No. 762
1886); we have so arranged our apparatus that the wires or rods from the signal
levers in the signal cabin, to the signal arms themselves, need not have any
connections or communications with the respective facing points or plungers, but
may as is usual with an ordinary sectional signal, run direct from the 'signal cabin
to the semaphore arm.
All existing systems of mechanically detecting the action of points and plungers,
where there are a series of facing points, are exceedingly inconvenient, as is well
known to any one well versed in the art, and to those responsible for traffic
working.
The ways in which we effect our invention are as follows. Where points are
locked by duplex plungers or simplex machines, we return a rod from each of the
plungers to the signal box, and make each such rod work a tappet or other inter-
locking connection so as to release all signal levers that apply for trains moving
over the said facing points in the particular plunged position, and to lock all conflicting
signal levers.
Simplex machines are point detectors, for as known in the art, neither plunger
can be worked, unless the switch points are properly home in the desired position.
It is obvious that with this class of point plunger or lock; detecting independently
the action of the switch points, is simply superfluous.
However wliere points are 'plunged with the ordinary single plunger or lock, then
we return one rod connection from the switch points and another rod connection
from the plunger (and if desirable one from the safety bar) to the signal cabin.
Both connections work tappets or other interlocking connections, the plunger
connection releases all signal levers that apply for trains moving over the said points;
and the switch point connection locks all signal levers that apply for trains moving

page_text: over the said points when normal, and releases all signal levers that apply for trains
moving over the said points when worked. The details would be varied to suit single
line or special working of traffic; and sometimes only one return rod would be
necessary in both of the herein before described methods.
It may be found convenient at times, instead of running the before mentioned rod
connections (both methods) to the signal cabin, to make them cross the return
connections of the facing points or plungers in the rear, at right angles so that the
rear facing points could only be worked and plunged accordingly as to whether the
facing points in advance have been correctly worked and plunged.
By this method instead of making the correlated signal connections detect for and
with all their respective facing points and plungers, each facing point and plunger
or plungers, would be detected by the facing point and plunger or plungers in
advance, so that the return connections from the last facing point and plunger or
plungers could be either run direct to the signal cabin and work interlocking con--
nections, as and for the purpose described; or the signal connection from the signal
lever to the semaphore arm, could cross at right angles the last return point and
plunger, or plungers connections and not as now travel through and detect all the
remaining points and plungers.
It may be found desirable and in many cases be much cheaper to arrange a
controlling or slotting apparatus (the mechanism of which is well known in the trade)
at or adjacent to the facing points, and fix a separate short connection from the
points, from the plunger or plungers and from the safety bar, to the controlling
apparatus, and one (or two if necessary) return rod, to the signal cabin.
Unless the safety har, plunger or plungers, and points, had worked correctly, the
return rod would not be actuated; and consequently the signals would stand locked,
through their levers.
The controlling apparatus would be a double or treble one and the return rods
(one or two) according to the circumstances of each case.
It is obvious that this method of return connections as hereinbefore described
would excellently effect the object of the first portion of my invention viz., detecting
the action of ground bars, it is also clear that the best method of carrying this into
effect is by running the usual working connection to the bar; and a separate detecting
connection from the bar to the signal cabin.
It should be understood that the return rod connections hereinbefore mentioned
are in addition to, and are quite distinct from, the usual connections which work the
said points and plungers.
We are aware of the probability that a return rod from switch points to a signal
cabin may have been used before, therefore we lay no claim to the use of such a rod
by itself.
Where one set of return rods crosses another set of such rods (as in my method
where one set of facing points and plunger or plungers detect for another such set)
we provide each set with suitable notches or the like, for the purposes of interlocking
with each other, and we make the return detecting rods work through a box or case
for greater convenience.
Canto 1988
JOHN PATRICK O'DONNELL,
Agent for the said Applicants."

page_text: COMPLETE SPECIFICATION.
Improvements in Working, Controlling, and Detecting Railway
Signal Apparatus.
We, JOHN PATRICK O'DONNELL of Shoebury Villa, Penrith Road, New Malden in
the County of Surrey Civil Engineer and Patent Agent, and LEICESTER BRADNEY
STEVENS of Darlington Works, Southwark Bridge Road, aforesaid 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:-
Our invention has reference to improvements in working, controlling and detecting
safety apparatus in connection with the facing points of railways principally, but it
also has reference to signalling apparatus generally.
The first portion of our invention consists in improvements in the working and
detecting the actions of all bars, used in connection with signals, except those that
work in conjunction with the plungers at facing points of railways.
It is a frequent practice to provide bars beyond the switches at the fouling of two
or more lines of railway, to ensure that the tail of the train has cleared the conflicting
line, before a signal through that conflicting line can be given "All Clear." It is
also customary on certain lines of railway to provide rear bars, (instead of duplicating
signals) where facing points are beyond the safe limit of distance to ensure that when
the signal is replaced to "Danger," the facing points cannot be reversed until the
train has passed over them.
Again among other applications of bars, there is that application where they are
used to prevent points (cross-over-roads, sidings fct.) which may be a considerable
distance from their respective fouling signals, from being opened or reversed, until the
train has passed over them.
In all applications therefore (with the exception of that before referred to) where
bars are used in connection with railway signals, it is highly essential that they should
have worked correctly before any correlated signal is given "All Clear."
The object of this portion of the invention then, is to prevent the respective signals
from being lowered, indicating the line safe and clear if any of the connections to the
said bars have given way, or if the bars have not gone correctly home in both
positions.
We attain this object by mechanism illustrated in the accompanying drawings.
Figure is a sketch plan of the facing points of a junction. A, represents the
Main Line, a one rail and a² the other. B represents the Branch Line, whereof b¹ is
one rail and the other. 1, is the Signal Cabin, 2. 3. 4. 5. 6. 7. are the usual rod and
crank connections working a fouling or safety bar 8,-9, 10, 11 are the return
connections working (the different applications of which form the subject of the first
part of our invention) the Junction Signal 12, and 13 is the Junction Signal for B.
Figure Il. is a sketch plan of a junction, D is the Branch Line, E the Main Line;
14 is the usual Safety Bar fixed at every junction working in conjunction with the

page_text: plunger, 15 is the Signal Cabin, 16. 17. 18 19. 20. 21 are the usual rod and crank
connections working a Rear Bar 22.-23. 24 25 are the return connections working
or slotting both the Junction Signals 26. 27.
Figure III. is a sketch plan of a line of railway, 28 is the Signal Cabin, 29. 30. 31.
32 33 are the usual connections working a Safety or Rear Bar 34. 35. 36. 37 are
return connections, 38 is a notch in the blade 37, 39 is a notch in the blade 31,-
40 is the box or case through which the blades pass and have their support, 41 is the
wire connection from the Signal Cabin working the Signal 43, and 42 is a blade
in that connection, 42" is a notch in the blade 42.
Figure IV. is a sketch plan of a line of railway, 44 is the Signal Cabin, 45. 46. 47.
48. 49 are the usual rod and crank connections working a Safety or Rear Bar 50.-
51. 52. 53. are the return connections, 54 is a notch in the blade 53,-55 is the box
or case through which the blades pass and find their support, 56 is the usual
connection from the Signal Cabin working the Signal 58, and 57 is a blade in that
connection; 57ª is a notch in the blade 57.
Figure V. is a sketch plan of a line of railway, 59 is the Signal Box, 60. 61. 62.
64. 65 are the usual rod and crank connections working a Safety or Rear Bar 66,-
63 is a notch in the tappet or blade 62,-67. 68. 69 are the return connections, 70 is a
notch in the tappet or blade 69,--71 is the wire connection from the Signal Cabin to
the Signal 76, 72 is a blade or tappet in that connection, 73. 74 are locks which
slide in the lock box or case 75.
Figure VI. is a sketch plan of a line of railway; 77 is the Signal Cabin, 78. 79.
80. 81. 82 are the usual rod and crank connections working a Safety or Rear Bar 83,-
81. 85 are the return connections, 86 is a notch in the blade 85,-87 is the box or
case through which the blades pass and have their support; 85 is the wire connection-
from the Signal Cabin working the signal 90, and 89 is a blade in that connection,
89 is a notch in the blade 89.
Figure VII. is a part section of one of the usual methods of weighting the Bar
back to its normal position in the event of a fracture in its connections, and 91 is a
part view of the wheel of any vehicle, the flange being upon the Bar 92,-93 is the
rocking shaft through which the bar is actuated; 94 is a section of the rail, 95 is the
counterbalance weight, 96 is the arm keyed to the shaft 93 to which the actuating
rod connection is attached.
Figure VIII. is a side view of Figure VII. 97 being the usual clip to support the
rocker for working the Bar. We do not bind ourselves to this or any other method
of counterbalancing the Bar, neither do we lay any claim to counterbalancing Bars
generally.
Figures IX. and X. are simply illustrations of alternative methods of detecting the
action of a Safety or Rear Bar other than a Bar working directly with a plunger at
Facing Points. 101 is the Signal Cabin; 101. 102. 103.. 104. 105 are the usual
connections working a Safety or Rear Bar 108,-106. 107 are continuations of the
connections, attached to a double crank 109. 110 (Figure X. 98. 99,) 111 is a single
rod connection, 112 is a counterbalance weight attached to a lever working with the
blade 113; 114 is a notch in blade 113; 115 is the usual wire connection from the
Signal Cabin to the Signal 118, and 116 is a blade in that connection and 116ª is a
notch in that blade, 117 is the box or case through which the blades pass and have
their support.
To the particular method illustrated in this figure we lay no claim although it would
be entirely novel as far as we know to connect to the Signal 118 direct off the
blade 113, without having an independent lever to work it.
The action of this portion of our invention is as follows-The signalman in Cabin 1
(Figure 1.) upon moving over his lever actuates. the Bar 8 through the rod and crank
connections 2. 3. 4. 5. 6. 7 and again through the Bar 8 and the return connections
9. 10. 11 the Signal 12 is actuated.
If therefore the Bar fails to work, the Signal remains at "Danger." The Bar is
made a part of the connections to the Signal.
A similar bar and connections on line A would work Signal 13, so that before

page_text: Signal 13 could be given for trains to proceed to B, vehicles would have to be clear
on Line A, otherwise should they be at the fouling and consequently on the bar the
Signal 13 could not be given as it would work through the Bar. The same explanation
refers to Bar 8 and Signal 12.
The action is similar in Figure II. where our invention is applied to a Rear Bar
upon the Facing Points. As the distance from the Facing Points to the Signals is so
great, a bar is used (suitably interlocked in the Cabin) to prevent the Facing Point
Lock and point levers being reversed immediately the signal arm is replaced to
Danger."
In this Figure the connection from crank 24 would be attached to both Signals
26. 27 and with the levers working those Signals would practically slot or co-act them.
In Figure III. the Bar 34 is worked by an independent lever through rod and
crank connections 29. 30. 31. 32. 33 the blade 42 is normally locked and is only
released by the working of both connections of the bar thereby presenting notches
39. 38 underneath the blade 42. The Signal is then free to be worked.
In Figure IV. and VI. the Bars 50 and 83 respectively are worked by independent
levers and the Bars must have worked and released through return connections 51.
52. 53 and 84. 85 the blades 57 and 89. The notch 54 releases blade 57 and thereby
enables Signal 58 to be lowered. The notch 86 releases the blade 89 and thereby
enables Signal 90 to be lowered. In Figure V. the rods 62. 69 are formed into
tappets. Normally the Signal is locked at "Danger" through the tappet 72. Before
this tappet can be worked the usual connections to the Bar 66 must have worked
bringing notch 63 opposite lock 74 and the return_connections from the Bar must
have worked bringing notch 70 opposite lock 73. The Signal 76 is now free to bo
worked, the tappet 72 in its action places locks 73, 74. into notches 63 and 70, thus
backlocking both connections of the Bar.
In Figure X. all connections (105. 106 and 107) must have been worked before the
connection 113 is worked to free the Signal Blade 116.
In all the preceding Figures the return connection (rod or wire) from the Bars may
run back to the Cabin and there release and lock in the locking apparatus the necessary
levers.
In that portion of our invention before described it is optional whether the Bars aro
counterbalanced, in some cases it may be desirable, whilst in others it would be
superfluous.
The second portion of our invention has for its object certain improvements in
detecting the actions of the switch points and of the facing point locks or plungers at
the facing points of railways.
In consequence of the inconvenience arising out of the present system of detecting
points and plungers through causing the wires from the correlated signals to pass
across or through blades from the said. points and plungers (as in Hancox's Specifica-
tion No. 5582 of 1884) or again through causing the wires from the correlated signals
to cross the lines of way at right angles to the plunger and parallel to the stretcher
bar (as in Kirby's Specification No. 762 of 1886) we have so arranged our apparatus
that the wires or rods from the signal levers in the Signal Cabin, to the signal arms
themselves, need not have any connections or communications with the respective
facing points or plungers, but may, as is usual with an ordinary sectional signal, run
direct from the Signal Cabin to the semaphore arm.
Existing systems of mechanically detecting the action of points and plungers where
there are a series of facing points are more or less inconvenient, as is well known to
any one well versed in the art, and to those responsible for traffic working.
The ways in which we effect our improvements are as follows-Where points are
locked by duplex plungers or Simplex machines, we return a rod from each of the
plungers to the Signal Cabin, and make each such rod, work a tappet or other inter-
locking connection so as to release all signal levers that apply for trains moving over
the said facing points in the particular plunged position, and to lock all conflicting
signal levers.
We attain this object by mechanism illustrated on the accompanying drawings.

page_text: Figure XI is a sketch plan of a right and left hand junction. The extreme junction
0. N. is a facing junction in one direction only, while the near junction P. Q, is facing
in two directions. By the aid of the Simplex Machine (Patent No. 2176 of 1888) only
one set of return connections 156. 157. 158 and 159 is necessary.
Simplex Machines are a kind of double or duplex point detectors, for as known in
the art, neither plunger can be worked, unless the switch points are properly home
in the desired position.
It is obvious that with this class of point plunger, detecting independently the
action of the switch points is simply superfluous.
The dotted lines shew what would be the return connections if the junction of O. N was
facing in both directions. Signal 163 applies for trains from Q to O and Signals 165
from Q to P. It is essential of course that the facing points should be properly home
and bolted in that position before either Signal should be lowered to safety. The
return connections 129 134 of the facing point lock worked by usual connections
120. 121. 122. 123. 126 are held normally locked. Again the levers in the Signal
Cabin working the Signals 163. 165 are held normally locked by these return
connections 129. 134. Upon the usual facing point lock connections 137 138. 139.
150. 153 being worked, the Simplex plunger 155 actuates the return connections
156. 157. 158. 159 to the extent that the notch 160 releases blade 129.
Upon now working over the usual facing point lock connections 120. 121. 122. 123.
126, the Simplex plunger 127 actuates the return connections 128. 129. 130. 131 to
the extent that the levers working signals 163, 164 are released and levers working
signals 165. 166 and 162 locked.
The Distant Signals may be released by the return connection in addition to the
Home Signal release. Upon the switch points of the junction of the line P being
reversed the selector-bar 126 (of the Simplex Machine) is placed out of gear with 127
and into gear with 132, the engaging arms being b²,
Upon the signalman now working over his facing point lock connections 120 fct.
the Simplex plunger 132 actuates the return connections 133. 134. 135. 136 to the
extent that the levers working the signals 165. 166 are released and the levers working
signals 163. 164 and 162 are locked.
In Figure XII is shewn a return rod from the switch points and from the more
usual single facing point plunger to the signal cabin.
The usual connections working the plungers 175 and 185 are not entirely shewn.
They appear broken off at 170 and 182.
The return connection at the junction of R and S, 172. 171. 170. 169, 168 from the
switch points and 177. 178. 178ª. 179. 180.. 181 from the ordinary plunger are
normally locked by the return connections at the junction of V and T 187 from the
ordinary plunger. Again the levers in the signal cabin 167 working the signals
197. 198 are themselves held normally locked by the return connections 194. 195. 196.
The points at the junction of V and T lie normally right for signals 197. and 198.
192 is a slot or ground co-acting apparatus and if the road T were not for opposite
running traffic to 1, the return rod 190 would have sometimes to be worked (as well
as and through the points) and sometimes remain normal. In the present instance
however, the points being right, the return rod 190 does not require to be moved for
the free passage of either of the blades 169. 180.
Again the return connection 190 is arranged in the slot 192 as though one of the
joint movements had been completed leaving it only necessary for the movement of
return rod 187 to actuate the return connections 193 194. 195. 196.
Upon the signalman working over his lever actuating the point lock connections
182 &ct. and inserting the plunger 185, he works the return connections 187 until the
notch 188 has moved forward to release or clear both blades 169. 180 of the return
connection of the plunger 175 and the points it locks. It also actuates the return
connections (through the slot) 193. 194. 195. 196 and actuates releases in the signal
cabin upon levers working 197. 198 signals.
Again the signalman working over his lever actuating the switch points at the
junction of R and S, works the return connections 172 171. 170. 169. 168, locks the

page_text: return connection 190 of the other switch points and releases in the signal cabin
signal 198.
Again in working over the lever actuating the plunger 175, the return
connections 178. 178. 179.. 180. 181 are worked, thereby completing the release upon
the signal 198 and its respective distant signal and locking signals 199. 197 &ct. in
the signal cabin, and also lock the switch points and back-locks the plunger of the
other facing points. Normally the return connections 172. 171 fct. free the signal 197.
Should the facing points at the junction of V and T be moved over, the return
connection 190 would lock both blades 169 and 180 and also lock the return con-
nections 193. 194 fet. through the co-acting apparatus.
It is obvious of course that in all the Figures XI. XII and XIII the working of
the return connections absolutely depend upon the correct working of the switch
points, plungers, and their respective usual working connections.
Figure XIII illustrates the return connections from the duplex plungers of the
Simplex Machines which act similar to those described and illustrated in Figure XI
as fixed at the junction of Q and P.
The usual connections working the points and plungers are omitted in Figure XIII.
Although our description refers to the use of rod for the return detecting con-
nections, we nevertheless do not bind ourselves to its use, but may if desirable use
wire as a substitute.
We are aware that certain styles of arranging a separate connection from the bar to
the plungers or a separate connection actuating with the plungers at facing points
have been used before. We therefore lay no claim to such uses of the said connections.
We are also conscious of the possibility that a return rod or wire from switch points
to a signal cabin may have been used before, therefore we lay no claim to the mere
use of such a rod or wire by itself.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed we declare that what
we claim is
1stly. For working a safety bar and a signal or Signals connecting the actuating rod
or wire to the safety bar, and the safety bar by a separate connection to the signal or
signals substantially as and for the purposes herein set forth.
2ndly. For working a safety bar and a signal or set of signals (by independent
levers) connecting the actuating rod or wire to the safety bar and a separate con-
nection from the bar to cross the signal connection or connections, the whole operating
as a bar and signal ground interlocking apparatus and detector substantially as and
for the purposes herein set forth.
3rdly. For working a safety bar, and a signal or set of signals (by independent
levers) connecting the actuating rod or wire to the safety bar, and a separate con-
nection from the safety bar, the whole operating and arranged, that when the bar is
worked its two connections release or present notches for freeing the working of the
signal (through its detecting blade as at F fct.) substantially as and for the purposes
herein set forth.
4thly. The improved bar and signal interlocking and detecting apparatus, con-
structed, arranged and operating substantially as hereinbefore described with reference
to Figures 1 to VIII inclusive of the drawings annexed.
5thly. In railway signalling apparatus the employment of a return (rod or wire)
connection or connections from the plunger or plungers (or from a safety or any other
bar) to the signal box for the purposes of actuating tappets or other equivalents
thereby interlocking with the necessary levers in the locking apparatus substantially
as and for the purposes herein set forth.
6thly. In railway signalling apparatus the combination of the employment of a
return (rod or wire) connection from the points, and a return (rod or wire) connection
from the facing point plunger to the signal box for the purposes of actuating tappets
or other equivalents in the locking apparatus, and thereby interlocking with the
nécessary levers, substantially as and for the purposes herein set forth.
7thly. In railway signalling apparatus, the employment of a return (rod or wire)

page_text: connection from one pair of points, interlocking on the ground with the actuating or
return connections of another pair of points, substantially as and for the purposes
herein set forth.
8thly. In railway signalling apparatus, the employment of a return (rod or wire)
connection from one facing point lock plunger, interlocking on the ground with the
actuating or return connections of another facing point lock plunger, or the actuating
or return connections of a pair or pairs of switch points, substantially as and for the
purposes herein set forth.
9thly. In railway signalling apparatus the employment of one return connection
(rod or wire) from the switch points a second return connection (rod or wire) from
the facing point plunger (and if desirable a third from the Junction Safety bar)
arranged in connection with a ground co-acting apparatus, and a return rod (to the
signal cabin, signal arm or points or plungers) the whole operating that the correct
action of the last mentioned return rod depends upon the perfect working of the
switches, lock, and safety bar, substantially as herein set forth.
Dated thin 20th dose of November 1888
JOHN P. O'DONNELL, M.I.M.E., &c.,
Agent for the Applicants.