Improvements in or relating to Railway Signalling and Switching Apparatus.
Year: 1899

page_text: Date of Application, 14th Feb., 1899-Accepted, 14th Apr., 1900
Improvements in or relating to Railway Signalling and Switching
Apparatus.
.A communication from THE CONTINENTAL HALL SIGNAL COMPANY, of Brussels,
in the Kingdom of Belgium.
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
This invention relates to an improved apparatus for controlling the movements
of signals and switches on a railway; and an object is to construct an inter-
locking or controlling apparatus having means for preventing a lever changing
its position in either direction before the track-switch has made its complete
movement.
A railway signalling and switching apparatus embodying this invention will
be described. Reference being had to the accompanying drawings, forming
a part of this specification, in which similar reference characters indicate corre-
sponding parts in all the views.
Figure 1 is a side elevation of one of the chain sheaves employed. Figure 2
is a perspective view of a portion of the switch-controlling mechanism.
Figure 3 is an end elevation of a portion thereof. Figure 3a is a detail view
thereof. Figure 4 is a perspective view of a portion of the signal-controlling
mechanism. Figure 5 is an end elevation of the same. Figure 5 is a detail
view thereof. Figure 6 is a perspective view of the two-armed signal.
Figure 7 is a sectional view showing a clutch mechanism employed for operating
the signal-arms. Figure 8 a side elevation of the track-circuit relay. Figure 9
is a perspective view of the polarized pole-changing relay. Figure 10 is a
diagram of the tracks, switches, and signals, and of the electric circuits.
Figure 11 is a diagrammatic view drawn on a scale to clearly show the operating-
circuits.
In the interlocking apparatus, which is placed in the signal-tower, in the
switch-operating mechanisin a series of locking-bars 1 is employed (Figs. 2 & 3).
These bars are mounted upon a series of switch-lever bars 2, (Fig. 2) and
there is designed to be a relative movement between said bars 2 and 1. The
several bars are mounted in a frame 3, and the bars 2 have connection with
switch-levers, 4. These switch-levers 4 have link connections 5 with lugs 6
on the inner ends of the bars 2. From the lugs 6 rods 7 pass loosely through
openings in blocks 8, mounted on the bars 1. The portion movable within the
opening in the block 8 of each rod 7 is made somewhat larger than the remain-
ing portion. The spring 9 bears at one end against a nut on the inner end of
the rod 7 and at the other end against a collar loose on the rod, and the spring 10
engages around the other end of the rod and abuts against the lug 6 and at the
other end against a collar loose on the rod 7 (Figs. 2 & 3). These springs 9
and 10 have a tendency to hold the bars 1 centrally over the bars 2.

page_text: Double-shouldered lugs 11 and 12 are secured to the upper sides of the bars 1
and are designed to be engaged by swinging latches 13 and 14, operating, re-
spectively, by electro-magnets, 15 and 16. These latches 13 and 14 are pro-
vided with armatures coacting with the cores of the magnets, and they are
pivotally connected to the uprights supporting the electro-magnets. It will be
here seen that the adjacent pivoted ends of the latches 13 and 14 are extended
in an upward direction, and between the upper ends of these upwardly-disposed
portions is placed an adjusting-screw 17, designed to destroy the effect of
residual magnetism. These latches and lugs are so placed that they engage
and momentarily hold the bar 1 when it has made one-half of its movement in
either direction. The remaining part of the movement of the bar 2 com-
presses the spring 9 or 10, as the case may be.
Figure 3 shows the bar 2 to have been changed from the reversed to a normal
position and now in the normal position. Its movement from reversed to normal
tended through the spring connection to carry the bar 1 also from the reversed
to normal position; but the latch 14 engaged the lug 12 when the bar 1 moved
halfway from the reversed to the normal and stopped the movement of the bar 1.
The bar 2 was, however, free to continue its movement as the spring connections
between it and the bar 1 yielded. The bar 7 is rigidly attached to the bar 2,
but slides loosely through the hole in the lug 8. The sleeves 117 and 118 are
also loose on the rod 7, so that the movement of the bar 2 toward normal posi-
tion compresses the spring 9 after the bar 1 is stopped by the latch 14. The
large part 119 of the rod 7 (Fig. 3) is thus partially withdrawn from the lug 8,
and the pressure of the spring 9 is brought to bear on the lug 8 and through it
pushes the bar 1 into normal position as soon as the latch 14 is lifted by the
electro-magnet 16. The bar 1 in Figure 3 is not in the normal position, but
is stopped in the middle position by the latch 14. When both bars 1 and 2
are in either the normal or reversed positions, the large part 119 of the rod 7 is
entirely inclosed by the lug 8.
In moving from normal to reversed positions the operations are the same,
except that the latch 13, lug 11, and spring 10 come into play instead of the
parts 14, 12 and 9.
The reason why a half-movement of the bar 1 is permitted before it is stopped
by the latch 14 is to put the indicator 120 (Figs. 2 & 3) carried by the bar 1
in the neutral position--that is, neither normal or reversed-whenever the
switch-operating lever is changed from one position to the other. The indicator
remains in this position until the track-switch makes its complete movement,
as explained elsewhere.
By means of the set-screw 17, above mentioned, when one of the latches is
raised the other is pushed down. This serves the purpose of destroying the
effect of residual magnetism in the following manner: suppose the magnet 15
to be energized and the latch 13 to be lifted. This releases the bar 1, which
under the influence of the spring 10 carries an elevated portion of the lug 12
under the point of the latch 14, lifting it and, through the set-screw 17, pushing
the latch 13 away from the magnet 15 after the current through the magnets
has ceased. This action is the same in either direction and is illustrated by
the two central bars shown in Figure 2, which are in complete normal and
reverse position, respectively.
If the switch-operating lever 4 be placed in position to effect the movement
of a track-switch and before the track-switch has made its complete movement
it be changed from that position to the opposite position suddenly, the effect on
the releasing-magnets 15 or 16 as the case may be, would be the same as
though the track-switch had made its complete movement in the opposite
direction to that in which it was moving at the time the current was cut off,
and the locking-bar 1 would be released, permitting other movement which
might be conflicting. To prevent this, a pawl 18 is pivoted to a bracket 19,
attached to the frame 3, and this pawl is pressed into engagement with the

page_text: bar 2 by means of a spring 20. A notch is cut in the edge of the bar 2, into
which the pawl is designed to engage before the switch-operating lever 4 has
moved far enough to break the circuit through the switch-operating motor, and
prevents reverse movement. of the lever 4. When the track-switch completes
its movement, the bar 1 is released and slides out past the point of the pawl 18
and the notch in the bar 2 and forces the pawl out of said notch, so that both
bars are free to move. The switch-operating lever 4 can now be put in the
other position. If an operator inadvertently tries to move the lever 4 too soon
and a notch in the bar 2 is made to receive the pawl 18, the pressure on the
pawl will prevent the complete movement of the bar 1, as the pawl will bear
against the wall of the notch, but if the lever 4 be put into proper position
and the pressure on the pawl removed the bar 1 will complete its movement.
The pawls 18 are employed at each end of the bars 2, or rather at each side of
the frame 3, to engage with opposite end portions of the bars.
In this application the switches and signals are worked by separate levers.
The signal-operating levers 21 are connected to bars 22, which carry and are
connected to bars 23 in the same manner that the bars 1 and 2 are connected
to the switch-operating levers. The construction and operation of the bars 22
and 23 are similar to the bars 1 and 2 in all respects, except that the bar 23
is locked by a latch 24 in only one direction and that in moving toward the
normal position corresponding to the "danger" position of the signal. The
latch 24 is lifted at the proper time by the electro-magnet 25, which is
energized by a current generated in the armature of the signal-operating motor,
which is caused to rotate by the turning of a counter-weight which places the
signal in a normal position.
It is unnecessary to lock the bar 23 by a latch when moving toward the
reverse position, because the signal is the last thing that is to be reversed,
nothing afterward depending on its making a complete movement in that direc-
tion. Of course the distant signals must not be reversed until after the home
signal is completely reversed; but this is secured by passing the distant-signal
circuit through a circuit-closer operated by the home signal.
The mechanism for operating the double signal, Figures 6 and 7, is similar
to that for operating a single signal, described in my Patent Specification
No. 317699, except that instead of one chain keyed to the shaft there are two
chain-sheaves 26 and 27, placed loosely on the shaft and carrying spring-
pressed pawls 28 and 29, which engage teeth in ratchet-wheels 30 and 31,
respectively. The ratchet-wheels 30 and 31 each have only one tooth, and these
and the pawls are so arranged that the tooth on the wheel 30 engages the pawl 28
when moving in one direction and the tooth on the wheel 31 engages the pawl 29
when running in the opposite direction. The ratchet-wheels 30 and 31 are
keyed to the shaft 32 of the signal-operating mechanism and rotate with it in
one direction or the other, depending upon the rotation of the motor-armature.
The parts are so proportioned that less than one revolution of the ratchet-
wheel 30 is sufficient to effect the reversal of the signal-arm. This is necessary.
because if more than one revolution were required the other ratchet-wheel would
pass its pawl. Then when the first signal returns to its normal position the
other pawl would catch and tend to reverse the other signal.
If it is desired to reverse the signal-arm 33, the signal-operating motor is
run in such direction that the ratchet wheel 30 engages the pawl 28 and causes
the chain-sheave 26 to rotate with it. At the same time the pawl 29 slides
easily over the periphery of the ratchet-wheel 31 and has no effect on the
signal 34. If the motor is run in the opposite direction, the ratchet-wheel 31
engages the pawl 29 and the pawl 28 slides easily over the ratchet-wheel 30
and the signal 34 is reversed. The signals 33 and 31 will be operated by the
winding of the chains 35 and 36 on the sheaves 26 and 27, thus moving the
pivoted levers 37 and 38 and moving the rods 39 and 40, which connect with
the signals.

page_text: The instrument which effects the reversal of the signal-operating motor is
shown in Figure 9. It is similar to the well-known polarized relay, except that
it has two contact-tongues 41 and 42, each of which can make contact with
either of two contact-posts. The tongues 41 and 42 are attached to the arma-
ture-lever 43, but insulated electrically therefrom and from each other. In
one position of the lever 43 the tongue 41 makes contact with a contact-point 44
and the tongue 42 makes contact with the contact-point 45. In the other position
of the lever 43 the tongue 41 makes contact, with a point 46, and the tongue:42
makes contact with the point 47 Of course the armature-lever143 will be swung
laterally to make the abovementioned contacts by means of the electro-magnet 48.."
In the track-circuit relay shown in Figure 8 the armature-lever 50 is re-
tracted by a weight 51. There is no objection to the weight on account of the
slowness of its action, as rapid action of the armature is not required in a relay
used for this purpose, and it has the following great advantage over a spring
when the relay is used for the purpose herein described. A weight when sus-
pended from a horizontal axis and free to mové about that axis will tend to
place itself in such position that its centre of gravity is vertically below the
axis, and the force required to push it out of its position will be zero at the
start, but will increase proportionally to the sine of the angle which a line
passing through the centre of gravity and the axis makes with the vertical,
and the actual force at any point will equal the weight multiplied by the sine
of the angle. Applying the weight to the relay-armature, as shown in the
drawings, the weight will be partially counter-balanced by the armature-lever.
This will cause the weight to hang at some point between the vertical and hori-
zontal, and the force required to. move it will be equal to the weight multiplied
by the sine of the angle which the line passing through its centre of gravity
and the axis makes with the vertical, less the counter-balancing effect of the
armature. The weight may be so adjusted as to size and relative position with
respect to the armature that the separation of the contacts 52 and 53 may be
any amount desired, and still the force required to draw the armature down
will be so small that any ordinary battery used in track-circuit work will exert
sufficient force. A wide separation of the contacts 52 and 53 is useful in work-
ing on high-potential circuits in order to break the arc formed. The armature-
lever has knife-edged bearings 54.
To more clearly illustrate the functions of the mechanism described above,
the operation of one of each of the different kinds will be described using the
diagrams in Figures 10 and 11. The normal position of all derails is open. The
normal position of the transverse switches is set for the main track, and the
normal position of all signals is at "danger." In Figure 10 everything is
shown in normal position. Suppose it is desired to give a clear track to a train
travelling in the direction of the arrow shown in Figure 10. Derails Nos. S
and 9 must first be reversed or closed. I will describe the operation of only
cne, as they are alike. First, the proper lever 4 Fig. 2 is to be reversed.
This pushes its bar 2 forward into reversed position and carries its bar 1 half-
way, where it is stopped by the lug 11, engaging with the latch 13, where it
remains until the track-switch completes its movement. The reversal of the
lever 4 also puts an electric switch-arm 55 (Figs. 2 & 10) in contact with the
contact-fingers 56. This closes the circuit of the generator 57, (Fig. 10) so
that the current flows through the wire 58, contact-fingers 56, switch-arm 55,
wire 60, contact 61, switch-arm 62, armature-motor 63, switch-arm 64, con-
tact 65, field of the motor 63, wire 66, contact 67, bar 68, (which normally
connects the contacts 67 and 69) contact 69, and wire 114 back to the
generator 57. This rotates the armature of the motor 63, closes and locks the
rail-switch, and reverses the pole-changing switch 64-62 as described in my
Patent Specification No. 35979. The reversal of the pole-changing switch breaks
the circuit named above and forms a new one, including the motor 63 and
magnet 15 belonging to this particular derail, so that the current generated in

page_text: the armature of the motor 63 by its rotation due to acquired momentum flows
from the armature of the motor 63 through the switch-arm 62, contact 78, field
of the motor 63, wire 66 contact 67, bar 68, contact 69, wire 114, wire 113,
magnet 15, contact 71, switch-arm 73, wire 74, contact 70, and switch-arm 64
back to the armature of the motor 63. This induced current serves a double
purpose that is, it serves to stop the rotation of the armature of the motor 63
and also serves to energize the magnet 15, (Figs. 2 & 3) which lifts the latch 13
and releases the bar 1, which under the influence of the spring 10 takes the
reverse position. The eighth and ninth bars 2 and the eighth and ninth bars 1
being reversed release the third and fifth of the signalling-levers 21 (Fig. 4),
operating the signals Nos. 3 and 5 (Fig. 10) governing this route. Signal
No. 3 is the one to reverse or clear for a train going in the direction indicated
by the arrow (Fig. 10). To do this, the third lever 21 is reversed. This puts
the third bar 22 and the third bar 23 (Figs. 4 & 5) in the position shown at
the left in Figure 4 and puts the electric switch-arm 75, carried by the lever 21,
in contact with a contact-piece 76. This closes the circuit of the generator 57
(Fig. 10) so that the current flows through the wire 58, contact 76, switch-
arm 753, wire 77, magnet of polarized relay 48, wire 79, switch-arm 75+, con-
tact 10, magnet 25, and wires 113 and 114 back to the generator 57. This
energizes the electromagnets of the polarized relay 48 and throws the arma-
ture 43 against either one of the magnetic poles, depending upon the direction
of the current in the magnet-coil and the polarity of the permanent magnet.
This deflection can be made right if wrong by reversing the connections on the
terminals of the magnet 48. After being once made right they need never after
be changed. The current maintained above will put a tongue 41 in contact
with a contact-point 44 and a tongue 42 in contact with a contact-point 45.
This closes another circuit of the generator 57, so that the current flows through
the wire 58, contact 763, switch-arm 75%, wire 77, contact 45, tongue 42, armature
of motor 84, tongue 41 contact 44, field of motor 84, brush 85, rotary switch-
arm 86, brush 87, rotary switch-arm 88, wire 66, contact 97, bar 98, contact 99,
wire 66, contact 67, bar 68, contact 69, and wire 114 back to the generator 57.
This energizes the motor, causing the ratchet-wheel 30 (Fig. 7) to rotate, so as
to engage the pawl 28 and rotate the chain-sheave 26. This puts the signal-
arm 33 into reversed or safety position. The circuit is broken by the
separation of the rotary switch-arm 88 and the brush 87 (Fig. 10) and maintained
through the brake-magnet 90, as explained in my Patent Specification
No. 3176 In this position of the signal No. 3 the rotary switch-arm 91 makes
contact with the brush 92, and if now the signal operating lever 21¹ be reversed
the circuit is established, so that the current flows from the generator 57
(Fig. 10) through the wire 58, contact 76', switch-arm 75', wire 93, motor 94,
brush 95, rotary switch-arm 96, wire 66, brush 92, rotary switch-arm 91,
wire 66, contact 97, bar 98, contact 99 wire 66, contact 67, bar 68, contact 69,
and wire 114 back to the generator 57. This reverses signal No. 1. The locking
bars 22 and 23 connected to the first lever 21, are in the position shown at the
left-hand side of Figure 4. This reversed position of the bars
22
and 23 locks the third hars 22 and 23 1:1 a similar manner to
that shown and described in my Patent 35979 with reference to the
bars b, c and a. The reversed position of the third bars 22 and 23 locks
the eighth bars 1 and 2 and also the ninth bars 1 and 2 in the reverse position.
In putting the different parts back into normal position the first thing to be
operated is the distant signal. When the first signal-operating lever 21 (Fig. 4)
is put into normal position, its locking-bar 22 is drawn back to normal position;
but the locking-bar 23 is stopped half-way by the latch 24 catching on the
lug 103, secured to the bar 23. The switch-arm 75 will be separated from the
contact 76 and put into contact with a contact-plate 104 (Fig. 4). This inter-
rupts the current through the brake-magnet 115 (Fig. 10) allowing the
signal to assume a normal position under the influence of its counterweighted
"

page_text: levers, and this closes another circuit, so that the current generated by the
motor-armature 94, driven by the descending counterweight, flows through the
brush 95, rotary switch-arm 96, wire 66, brush 92, switch-arm 91, wire 66,
contact 97, bar 98, contact 99, wire 66, contact 67, bar 68 con-
tact 69, wire 114, wire 113, magnet 251 (Fig. 10), contact 104'
(Fig. 4), switch-arm 751 and wire 93 back to the motor 94. This
current retards the fall of the counterweight and energizes the magnet 251,
causing it to lift the latch 24, releasing the locking-bar 23, which, impelled by
the spring 105, returns to the normal position. This releases the locking-
bars 22 and 233 and the signal-operating lever 21. If now the third signal-
operating lever 21 is put back to normal position, its bar 22 is drawn back to
normal position, but its bar 23 is stopped half-way by the latch 24. This
movement of the lever 21 also separates the electric switch-arm 75 from the
contact 76 and puts said lever 753 into contact with the contact-plate 1043.
This breaks the circuit through the brake-magnet 90, releasing the signal No. 3
and establishing a new circuit, so that the current generated by the motor 84
(Fig. 10) flows through the tongue 41, contact 44, fields of the motor 84,
brush 85, rotary switch 86, brush 87, rotary switch arm 88, wire 66, contact 97
bar 98, contact 99, wire 66, contact 67, bar 68, contact 69, wire 114, wire 113,
magnet 253, contact 1043, switch-arm 75%, wire 77, contact 45, tongue 42, back
to the motor 84. This energizes the third magnet 25 releasing the locking-
bar 23 (Fig. 4) and allowing it to go to its normal position. This releases
the eighth and ninth locking-bars 22 and the switch-operating levers. The
derails Nos. 8 and 9 can now be restored to normal position; but I will describe
the operation of only one, No. 9 as they are alike. Putting the ninth switch-
operating lever 4 (Fig. 2) into normal position draws the bar 2 back to normal
position; but the bar 1 is stopped half-way by the latch 14. It also puts the
electric switch-arm 55 (Figs. 3 & 10) into contact with the contact-fingers 59
instead of the fingers 56 and the switch-arm 73 into contact with its contact-
plate 72. This closes a circuit of the generator 57 (Fig. 10), so that the
current flows through a wire 107, post 108 and lever 109 of the track-relay 110,
a post 111 and lever 112 of the next track-relay, contact 72, switch-arm 73,
wire 74. contact 70, switch 64, armature of motor 63, switch-arm 62, contact 78,
fields of motor 63, wire 60, contact 67, bar 68, contact 69, and wire 114 back to
the generator 57. This current has the effect of opening the rail-switch of
No. 9-that is, putting it in normal position--while at the completion of this
movement the pole changing switch is reversed, breaking contact with other
contact pieces. This interrupts the current from the generator 57 and makes
a new circuit, so that the current generated by the rotation of the armature 63
flows through the switch-arm 64, contact 65, the field of the motor 63, wire 66,
contact 67, bar 6S, contact 69, wire 114, wire 113, magnet 16 contact 59, switch-
arm 55, wire 60, contact 61, and switch-arm 62 back to the motor 63. This
energizes the ninth electromagnet 16 and lifts its latch 14, (Figs. 2 & 3) re-
leasing the locking-bar to return to a normal position, actuated by its spring.
This releases the switch-operating levers controlling switches on opposite
routes.
It will be noticed that the circuit which opens the derail passes through
the contacts of the track-relay 110 and the next one to it (Fig. 10). The
magnets of these relays are energized by currents derived from the track-
batteries 115 and 116 and through the track-rails. When a train is on any
portion of the track between said batteries, the current will be shunted and cut
off from one or both of the relays and their contacts will be separated, opening
the circuit which conveys current for opening the track-switch.
This prevents opening of the track-switch under the train.
Certain of the switch-operating levers 4 are connected mechanically together
in pairs, as shown at the left-hand side of Figure 2. By reversing the fourth
signal lever 21 the electric current is put through the switch-arm 75 and

page_text: through the contact-plate 76, (Fig. 10) closing a cireuit of the generator .57,
so that the current flows through the wire 58, contact 76, switch-arm 75%,
wire 79, magnet 48 of polarized relay, wire 77, switch-arm 75, contact_104",
magnet 253, wire 113, wire 114 back to the generator 57. This current passes
through the magnet 48 in the opposite direction to that sent through it when
the signal operating lever 213 was reversed. The lever 43 (Fig. 9) is thrown
to the other side and the tongues 41 and 42 make contact with the contacts 46
and 47, respectively. This closes another circuit of the generator 57, (Fig. 10),
so that the current flows through the wire 58, contact 76, switch-arm 75*,
wire 79, contact 46, tongue 41, armature of the motor 84, tongue 42, contact 47,
the fields of the motor 84, brush 85, rotary switch 86, brush 87, rotary switch 88,
wire 66, contact 97, bar 98, contact 99, wire 66, contact 67, bar 68, contact 69
and wire 114 back to the generator. This current flows through the armature
of the motor 84 in the opposite direction to that sent through it when the third
signal-operating lever was reversed. This rotates the ratchet-wheels 30 and 31
(Fig. 6) in the opposite direction, causing the ratchet-wheel 31 to engage the
pawl 29, the ratchet-wheel 30 remaining inoperative. This brings signal No. 4
into safety" position. Putting the fourth signal-operating lever back into
normal position releases signal No. 4, which, returning to the normal position,
generates a current that releases the fourth locking-bar 23 in the same manner
as before described for No. 3.
66
The
When the lever 43 (Fig. 9) of the polarized relay is thrown to either side it
remains there on account of the attraction of the permanent magnet until a
current is sent through the electromagnet in the opposite direction.
current which energizes the magnet 48 of the polarized relay when signal No. 3
is to be operated passes also through the fourth magnet 25, and when signal
No. 4 is to be operated it passes through the third magnet 25 (Fig. 10) but this
has no effect as the locking-bar under the magnet that current is passing through
must be necessarily in the normal position.
To more fully describe the operation of the pawl 18 in connection with the
notch in the bar 2 a specific movement of the switch-operating lever 4 will be
described. The lever 4 (see Figure 2) and the bar 2 (Fig. 2) connected thereto
have just been moved from the normal to the reversed positions for the purpose
of closing or reversing the track-switch operated thereby and for locking levers
controlling switches on opposing routes. During the rotation of the motor,
which effects the reversal of the track-switch, the bar 1 is held in the middle
position by the latch 13 (Fig. 3) engaging the lug 11, which stops it when
it has made one-half its movement-in this case from the normal to the reversed
positions in consequence of which the spring 10 is compressed by the con-
tinued movement of the bar 2. The complete movement of the bar 2 will carry
the notch in its edge past the front of the pawl 18. If now while the bar 1
is held in the middle position the operator should attempt to put the lever 4
and the circuit closers and the bar 2, connected to it, into the normal position
again, the movement would be prevented by the pawl 18 engaging the notch
in the bar 2; but when the track-switch is completely reversed the current
generated by the switch-operating motor armature, described elsewhere in the
Specification and also in my Patent Specification No. 3597, circulates in the
coils of the magnet 15, causing it to lift the latch 13, thus releasing the bar 1,
which under the influence of the spring 10 moves to complete reversed position.
In this position of the bar 1 it covers the notch in the bar 2 and holds the
pawl 18 away from engagment with the notch, so that it will not prevent the
movement of the bar 2 back to normal position.
In Figure 2 the bar 2 is shown in its reversed position, and in Figure 3 it
is shown in its normal position, while in both figures the bar 1 is shown in the
middle position. If it were not for the pawl 18, the operator could change the
position of a switch-operating lever while the switch-operating motor was still
running that is, before the track-switch is completely open or closed, as the

page_text: 21
case may be, thereby cutting off the current from the generator to the motor
and closing the independent motor-circuit, thereby releasing magnet 15 or 16. *
The transverse bars (Figs. 2 & 4) are connected to and operated by the
switch-levers.
1..
In Figures 3 and 5ª are shown the several contacts in their true position.
The wires in practice are connected to the metal blocks 56, 59, 71 and 72, which
support the contact springs or fingers, and the metal supports 55 and 73,
which support the bars 55 and 73. In the normal position of the lever 4 the
bar 55 bridges 55° and 59, and 73 bridges 73 and 72 and in the reverseil posi-
tion 55 bridges 55 and 56, and 78 bridges 73ª and 71. In the normal position
of the lever 21 the bar 75 bridges 75ª and 104, and when reversed it bridges 75*
and 76.
The switch 91 engages 92 when the home sigual to which it is attached is in
safety or reversed position, thus permitting the current to reach the 'distant
signal only when the home signal is in safety position. The bar 98 bridges 97
and the corresponding contact when the track-switch is closed or reversed, so
as to permit the current to reach the signals governing the movements on that
track only when the switch is in the proper position.
"
For the purpose of clearness in the claims I will term the locking bar 2 as a
primary" locking-bar and the locking bar 1 as a "secondary" locking bar.
Having now particularly described and ascertained the nature of this inven-
tion, as communicated to me by my foreign correspondents, and in what manner
the same is to be performed, I declare that what I claim is:-
29
1. In a railway signalling and switching apparatus a series of operating-levers,
primary and secondary locking-bars, connections between the primary bars and
levers, yielding connections between the primary and secondary bars, holding
latches for the secondary bars, and electrical means for releasing the latches,
substantially as described.
2. In a railway signalling and switching apparatus, a series of operating
levers, primary and secondary locking bars, arranged in pairs, one upon the other
connections between the primary bars and levers, spring yielding connections
between the pairs of bars, and electrically actuated locking devices for the
secondary bars, substantially as described.
3. In a railway switching apparatus, a series of operating levers, primary
and secondary locking-bars arranged in pairs, one upon the other, link connec-
tions between the primary bars and levers, spring-yielding connections between
the primary and secondary bars, two latches for controlling the opposite move-
ments of each secondary bar, spring-pressed pawls, one at each end of each
primary bar, adapted to engage notches in the primary bars and hold said
primary bars until released by the secondary bars and electromagnetic means for
lifting the latches and releasing the secondary bars substantially as described.
4. A railway switching mechanism, comprising operating-levers, primary and
secondary locking-bars, link connections between the primary bars and levers,
spring-yielding connections between the primary and secondary bars, holding-
latches for the secondary bars, electromagnets for raising the latches, and a
switch-operating motor by means of which the magnets are energized at the
proper time by currents generated by the rotation of the switch-motor momentum
substantially as described.
5. In a railway-switch-operating mechanism, a series of operating levers,
circuit-closers carried by the levers, primary and secondary locking-bars, link
connections between the primary bars, and levers spring yielding connections
between the primary and secondary bars, holding latches for the secondary bars,
spring-pressed pawls for holding the primary bars until the secondary have made
complete movement, electro-magnets for lifting the latches, and electric circuits
comprising the switch-operating motor, an automatic electric reversing-switch

page_text: operated by the motor, the circuit-closers attached to the operating levers, the
electro-magnets and the electrical connections substantially as described.
6. In a railway signalling apparatus, a signal, a motor for reversing the
same, a counterbalanced lever for restoring the signal to normal position and
rotating the motor in the reverse direction, a signal operating lever, a two-
position circuit-closer attached to the lever, a primary locking-bar, a secondary
locking-bar, a link connection between the primary bar and lever, a spring-
yielding connection between the two bars a latch for controlling the movement
of the secondary bar, and an electro-magnet for raising said latch, the said
magnet being in a circuit leading from the motor and energized by a current
generated by the reverse rotation of the motor, substantially as described.
7. In a railway signalling apparatus, two semaphores or signals, a motor,
sheaves loosely mounted on the shaft of the motor, à clutch mechanism between
said shaft and the sheaves, the said clutch mechanism operating to rotate the
sheaves in opposite directions when the motor is reversed and connections
between said sheaves and semaphores or signals, substantially as described.
8. A railway-signal, comprising two swinging signals, a motor for operating
the same, two sheaves loosely mounted on the shaft of the motor, a single-toothed
ratchet-wheel arranged at one side of each sheave, pawls carried by the sheaves
for engaging the said teeth, counterbalanced levers on the support for the
signals, connections between the sheaves and levers, and connections between
the levers and signals, substantially as described.
9. In a railway-signal-operating mechanism, two semaphores or signals, a
reversible electric motor for operating the signals, a clutch mechanism on the
shaft of the motor for selecting either one or the other signal depending on
the direction of rotation of the motor, a polarised pole-changing relay for deter-
mining the direction of current through the motor-armature, a two-position
circuit-closer attached to each of the two signal-operating levers, one for each
signal, said circuit closers acting conjointly to control the circuit through the
polarised relay and severally to control circuits through the motor, a generator
and the electrical connections, substantially as described.
10. The complete railway signalling and switching apparatus substantially
as described or illustrated in the accompanying drawings."
Dated this 14th day of February 1899.
BOULT & WADE,
Agents for the Applicant.