Improvements in Electrical Apparatus for Operating Railway Points and Signals.
Year: 1898

page_text: Date claimed for Patent under Sect. 103 of Act,
being date of first Foreign Application (in 24th Feb., 1898
France),.
Date of Application (in the United Kingdom), 23rd Sept., 1898
Complete Specification Left, 23rd Sept., 1898-Accepted, 3rd Dec., 1898
COMPLETE SPECIFICATION.
Improvements in Electrical Apparatus for Operating Railway
Points and Signals.
I, THEOPHILE Ducousso, of No. 3, Rue St. Beuve, Paris, France, 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 relates to electrical apparatus for operating railway points and
signals, this apparatus being such that all the points and signals of a station can be
worked from a single centre.
In order to render the description clear I shall first briefly describe the receiving
apparatus, the line and the working gear, these three parts being afterwards
described in their. different phases of operation in such combinations as ensure
safety.
Usually the points and signals are arranged to move alternately, and often they
should be furnished with systems of locking to prevent accidental change of position.
The points also are sometimes provided with safety bars preventing their movement
while a carriage is over the bar. Such chiefly are the usual conditions which have to
be kept in view in the course of the following description.
The receiving apparatus comprises an electric motor capable of revolving alternately
in opposite directions, for instance a dynamo having two fields wound in opposite
directions each communicating by a line wire with the working station, and an
armature connected at one end to the junction of the two fields and at the other
end to a return wire or earth. If at the working station one of the line wires
is connected to the one pole of a dynamo or battery, the other pole of which is
connected to the return wire or earth, the motor will revolve in the one direction,
whereas the rotation will be reversed if the connections are made to the other
wire.
Figure 1 shews the arrangement for transmitting notion from the motor M
to the point or safety rod A. The inotor shaft has on it a sleeve J which has a finger
driving a sleeve K fixed on the shaft of a worm V which gears with a wheel R loose
on the axis 0, and having a crank pin and roller F, which works in a slot E e of a
lever D fixed on a rocking shaft C which has an arm B jointed to the rod A of the
point or signal. The slot has a straight part e, and a part E having for its sides

page_text: circular arcs each concentric with the wheel R when the lever D is in its extreme
positions corresponding to the symmetric arcs H H¹ which are separated by an arc I
of about 180°. The sum of the three ares H, I and H¹ is the extent through which
the wheel R revolves for a complete stroke of the point or signal rod A.
The arc I
corresponds to the actual movement of the rod, the arcs H H¹ to the unlocking and
locking actions. If the parts are in the positions shewn in full lines in Figure 1 a
current is sent causing the motor and worm to turn the wheel R in the direction of
the arrow G the crank F does not inove the lever D while it traverses the arc H,
because the side of the slot is concentric with its rotation; but throughout the are I
the crank F acting in the straight part e of the slot moves over the lever D to the
left moving B from its position 1 to position 2, moving the rod A the distance a
required for working the point or signal. While the crank continues its movement
along the arc H¹ it acts on the concentric part of the slot E holding the lever D in the
dotted position. The current is automatically cut off from the motor a little before
the crank F reaches the end of the slot E as will be hereafter explained.
On looking at Figure 1 it is obvious that the two extreme positions of the lever D
as shewn respectively in full and dotted lines are symmetrical. Consequently if
the current be sent by the other wire causing the motor to revolve in the opposite
direction, the end of the rod A will be moved from position 2 to position 1 in the
manner described for the opposite movement. The locking of the point or signal is
effected by the position of the crank F in the slot E only when the movement of A
has been completed in either direction. For applying the mechanism to a point
having a safety bar, I fix on the wheel R, a cam L Figure 2 having two opposite
parts of its periphery-concentric-but of different radius. Against. this cam bears a
roller N of a lever P fixed on a rocking shaft Q the arm S of which is jointed to the
rod T of the safety bar. In a state of rest, the apparatus being in the one or the other
of its two normal positions, the roller N bears against the hollow of the cam L. The are
occupied by the part where the radius changes corresponds with H in Figure 1 so
that while the wheel R is caused by the motor to traverse the are H, the rolier N is
moved away by the cam moving the arms P and S to the dotted position and the
joint of the rod T from 1 to 2 raising the safety bar in the usual way if there be no
carriage over it. But if there be a carriage over the bar, it cannot rise, the
arms P and S cannot move from their original position and the roller N prevents the
cam L from rotating and thereby prevents the wheel R and the motor from
revolving. The motor is so constructed that it can sustain the current even when it
is persistently locked. The cam L is so set that the point or signal rod does not
begin to move until the safety bar is quite raised, and the bars held raised during
the movement of the point, not descending until this movement is completed when
the roller N reaches the opposite hollow of the cam.
Figures 3, 4 and 5 shew the arrangement of the rapid commutator which I
employ for changing the connection of the motor to the line immediately on the
movements necessary for safety being completed by the motor.
In a plane parallel to that of the wheel R, I arrange a rod V V₁ which can slide in
fixed guides u us and has its middle part V2 larger, on which slides a sleeve X.
Two helical springs u u¹ abut against the guides u² us and urge the sleeve X in
opposite directions by washers xx¹ free to slide ou V V¹ which has its one end jointed
to an arm W of a rocking shaft W₁, which has another arm W2 jointed to a control
rod Ws which is connected to a part moved by the point or signal so that the
rod V V¹ moves with the point or signal,
The sleeve X carries a forked spring y insulated, this spring, as shewn in Figure 4,
serving according to the position of X to connect the contacts 1 and 2 or the
contacts 3 and 4 which are fixed on an insulating base, 1 and 3 connected to the
two wires of the line, and 2 and 4 to the two windings of the field of
the motor.
The sleeve X of the commutator does not move with the rod V V¹ but after it, as
determined by the position of the wheel R which has two studs y¹ y² meeting
the end of a lever y which is pivotted at Y* and has an end Y¹ forming a stop for the

page_text: sleeve X, being held in the position shewn in Figure 5 by a spring y³. The action
is as follows:-
Figure 3 shews the commutator in one of its two normal positions corresponding
The current in this case
to the position of the moving. parts shewn in Figure 1.
comes to the contact 1 passes by the fork y to the contact 2 and thence through the
motor to earth. The wheel R moves in the direction of the arrow G and before the
crank F has completed the arc H the stud y¹ sets free the lever Y, the end Y¹ of
which locks the sleeve X. While the crank F traverses, the arc I, moving the point
or signal as above described, the rod Ws transmits the motion of the point or signal
to the rod V V1 until the crank F has completed the arc I, at this time the spring u¹
is compressed by the washer x¹ but cannot act on the the sleeve X which is urged by the
spring but is locked. When the crank F has traversed about half of the arc H¹,
the study moves the lever Y which releases the sleeve X allowing it to be moved
suddenly by the spring u inoving the forked commutator y from the contacts 1 and 2
which become insulated to the contacts 3 and 4, thus, preparing the connections for
the opposite movements and also transmitting the control of the movements made
to the operating station. After the opening of the circuit, the motor may slow down.
The end Y!
continuing, the motion of the wheel R and crank F through the arc H¹.
of the lever Y is kept away from the sleeve, X, until by the movement opposite to
that described, the stud y turning with the wheel R sets the arm Y free, which occurs
at the beginning of the subsequent operation. This inverse operation is substantially.
the same as that described, but it is the stud y¹ which then releases the commutator.
When the apparatus is in one of its normal positions, as in Figure 3, if the point
or signal worked by it should be accidentally displaced, as for instance by a forcing
of the points, there is fracture of some of the connections as for instance the rod A
(Figure 1) but the rod W3 (Figure 3) nevertheless communicates to the rod V V¹ the
movement corresponding with that of the point or signal to its new position, and in;
this case the sleeve X, not being locked by Y¹ also moves, shifting y from the
contacts 1, 2 to the contacts 3, 4, which, as will be hereafter described informs the
operator at the transmitting station of the accident.
The arrangement of the control commutator as described acted on by a rod Ws
connected to the point or signal is the most effectual for safety; but in many cases,
for example, for points in sidings it is thought sufficient to control only the motor
part of the apparatus. The end of the rod V V¹ may in that case be connected
to an eccentric pin on an extension of the lever D, the rod W and lever W W
being dispensed with, as shewn in the general plan Figure 6 and in the section
Figure 7 on Z Z1, Z2 Z3. As the same reference letters are used to indicate like,
parts in all the Figures 1 to 7 inclusive, it is unnecessary to, farther explain
Figures 6 and 7.
;
The line consists of two conducting wires and a return which may be a third wire
insulated or not, or the rails, which serves for all the apparatus of the same installa-.
tion. The line may be underground and so protected from accidents such as:
confusions or fractures to which exposed wires are liable; but the line may neverthe-
less be exposed, and I shall hereafter state the necessary arrangements to be
employed, so that safety may not be compromised whatever be the condition of the
line.
The transmitting apparatus is shewn in side view Figure 8 and transverse section
Figure 9.
A frame 1 has fixed on it an axis 2 around which can turn the operating
lever 3, 4, 5; mounted behind the frame; a cam 6, termed a drawing cam is also
pivotted on the axis 2 in front of the frame'; a commutator 7 for three contacts 8,
9, 10, and a reversing switch having two arms 11 and 12 for three contacts 13, 14
and 15 are mounted on a plate of marble or other insulating material 16 fixed on
the frame 1. There is also fixed on the frame a control electro magnet 17, having.
its armature always on one of the cores, on which it pivots when the magnet is
excited.
To the armature is fixed a lever 18 having its end jointed to a rectangular metal

page_text: bolt 19 which is notched at 20 and slides vertically in a hole of the frame, its weight
keeps the arinature away from the magnet except when it is excited; the upper end
of the bolt does not project beyond the circular edge of the frame, but the notch 20
is under the circular path of a stud 21-projecting from the lever 3, and prevents the
lever from being moved.
When the magnet 17 is excited, the lever 18 raises the bolt which then projects
beyond the edge of the frame, but its notch 20 allows the stud 21 to pass and the
lèver 3 to be inoved forwards.
On the lever 3 moreover is pivotted at 22 a double pawl 23, 24 right and left
handed; Figure 10 is a sectional plan on the axis 22 shewing the shape of the pawls
and the free space between them. The edge of the frame forms an arc on which the
pawls bear by their weight and it has two notches 25 and 26; also the cam 6 has two
shoulders 27 and 28 projecting beyond the circular edge and in the paths of the
respective pawls, and has two notches 29 and 30 like 25 and 26 in shape but not so
far apart. The cam 6 has a crank pin 31 connected to the reversing switch by the
rod 32 which ensures the joint movement of the two parts, and which is insulated
from the switch. The arm 5 of the lever is connected to the commutator by an
insulated rod 33 having a slotted hole which allows a little play in transmitting the
movement of the lever to the commutator. The arm 4 of the lever is connected by
the rod 34 to the locking bar 35 which may effect locking according to any known
system. The frame 1 is fixed on beams 36 to which are attached the other operating
mechanisms belonging to the station.
The operation of the mechanism is shewn in different phases in Figures 8, 11 and
12, the two latter figures shewing also diagrammatically the electrical connections
with the motor consisting of the armature 37 and the two field coils 38 and 39, their
commutator being indicated simply by a pair of blades 40 and 41 and two contacts 42
and 43..
In Figures 11 and 12 like reference numerals are used for like parts in Figures 8,
9 and 10.
The armature 37 is connected to earth or the common return and the two field
coils 38, 39 are connected to the line wires by the commutator 40, 41, these wires
meeting the blades 11, 12 of the reversing switch. The middle contact 14 of the
switch connects to the electro-magnet 17 and by it to the positive terminal of a
battery or dynamo, the other terininal of which connects to earth or the common
return wire. The positive terminal of the battery or dynamo has also a connection
to the contact 9 of the commutator the arın 7 of which is connected to the contacts 13
and 15.
Normally as will be explained hereafter, the position of the point or signal is
always in accord with that of the operating-lever. Thus in Figure 8 the lever is to
the right, like the receiving commutator in Figure 11. The movement of the lever
from the position in Figure 8 to that in Figure 12 which are the two extreme or:
normal positions can take place only under certain conditions.
First the locking bar 35 must be free, and if so, the lever can at once be moved to
the position in Figure 11 without doing anything until the pawl 24 drops into the
notch 25, this movement shewing that the lever is free, but at this moment the
play of the rod 33 is done with, and the lever 3 then moves the commutator arm 7
on to the contact 9, in which condition the lever is stopped by the stud 21 against
the bolt 19. The lever cannot be moved back because the pawl 24 is in the notch 25,
and the slight motion allowed is only equivalent to the play in the slot of 33 so that
the commutator 7 is not altered.
In the position Figure 11 the current passes from 9 to 13 and by 11 to line, and
by the commutator 40 and contact 42 to the field coil 38 and the armature 37 of the
motor and thence to earth. The motor then acts as above described moving
the points or the signal, and when it has done so breaking the contact 40, 42, and
making the contact 41, 43. The current then excites the magnet 17 and passes
by 14 and 12 to line, and by 41, 43 to earth through the field coil 39 and armature 37;

page_text: but this current owing to the resistance of the control magnet coil 17 is too weak to
work the motor in the opposite direction, but it helps to stop it. The lever 18 of the
magnet lifts the bolt 19 allowing the lever 3 to be moved over to the end of its stroke
as shewn in Figure 12. In the last part of its movement it moves the commutator arm 7
on to the contact 10 and the pawl 23 having met the shoulder 28 of the cam moves
it, advancing the rod 32 and thus changing the reversing switch 11, 12, thus
preparing the electric connections for the succeeding operation in the opposite
direction, the line 11, 40 which has just transmitted current being ready for controlling
the next operation and the line 12, 41 which has just served for control being ready
for transmitting current for the next operation.
The movement of the cam 6 from the position in Figures 8 and 11 to that in
Figure 12 serves also to bring a full part to the notch 25 and a hollow part to 26,
thus preparing the pawls 23 and 24 for the succeeding reverse movement.
Thus during the last part of its movement the lever 3, 4, 5, symmetrical with its first.
part, moves the locking bar 35 as required for its new position. It will be seen from
Figures 8 and 12 that for the two extreme positions of the operating lever all the
movable parts occupy two symmetrical positions, so that the same phases as those
described occur in their reverse movement. Assuming the apparatus to be for
actuating points, and that the normal condition shewn in Figure 12, has been put
wrong by forcing the point, still as above described, the commutator operates so
that the contacts 41, 43 are broken and 40, 42 are closed, then the current passes'
through the coil of the magnet 17, the contact 14, the line 11,40 and through the
motor to earth. The magnet 17 raises the bolt 19 which prevents the lever 3 from
being moved as the pawl 21 meets the bolt, consequently the points must be rectified
before the lever can be worked. For such a case it may be useful to have an audible-
signal such as an electric bell arranged in shunt with the magnet 17 and sounding'
whenever the inagnet is excited, that is to say, during each operation from the time'
when the control current is established until it is interrupted by the completion, of
the movement of the operating lever. Thus the electric bell would continue to sound
when the corresponding points are forced. A like result would be obtained by
inserting a bell in the common wire leading from the battery to all the electro
magnets 17 of the station, with a galvanescope in shunt to each, so that there
would be an audible signal for all the levers and a visible one for each.
Owing to the mode of operating described it results that whenever the lever 3
is moved to transmit it cannot be moved back to its initial normal position, without
first moving it quite over to the normal position corresponding to that of the
receiving apparatus, which moreover is possible only after reception of the control.
current sent by the receiving apparatus itself, after it is has taken the required position.'
The effect of this control, is that the operating lever must always be in accord 'with
the receiver. When an operating lever works several points or signals, the
corresponding receiving dynamos are connected parallel on the transmitting line, so
that they work simultaneously. But the passive resistances of these different
apparatus may vary and cause a sensible difference in the times occupied in completing
their movements, consequently the control current should not reach the operating.
station to disengage the bolt there until all the apparatus have attained the required
position.
For operating several sets of apparatus I adopt the arrangement shewn in Figure 13
in which three sets Z1 Z2 Z3, have their commutators field coils and armatures denoted
by the same ininerals as in Figures 11 and 12. Each apparatus has a second or
control commutator like that shown in Figure 4 acted on by the same sleeve and
having its contacts on the same insulating plate.
For simplicity of description have shewn these commutators in Figure 13 in the
same form as the primary commutators, 44 and 45 being the springs and 46 and 47
he contacts.
In the most distant apparatus Z³ the springs 44 and 45 are connected together and
o earth and the contacts 46 and 47 are connected by insulated wires to the

page_text: corresponding springs of Z2, the contacts of which are similarly connected to the
springs of 7, the two lines 11 and 12 thus taking the double control currents for all
the apparatus. The main lines 11 and 12 starting from the blades of the reversing
switch 11, 12 of Figure 12, go to two armatures 50 and 54 of two electric magnets 51
and 48. The wire 11 thus connects to the contact 49 and thence to the magnet 48,
and the springs 41 of all the apparatus. Similarly the wire 12 passes by 54 to
contact 53, magnet 51 and the springs 41 of all the apparatus. In fact the circuit of
each wire has its contact determined by a relay worked from the other wire, and
thence with the coil of a relay the contact worked, by which controls the other wire,
and thence to the motors. The armature 50 of the relay 51 has an angle arin strained
by a spring and having its end arranged to become locked, when the relay 51 is
excited, by the armature 57 of a magnet 59 so that it cannot be unlocked and the
armature 50 cannot leave the magnet pole 51 except on two conditions aiz―the
armature 57 must be attracted by its magnet and 50 must be no longer attracted
by 51.
In like manner the armature 54 of the relay 48 has an angle arm and spring
arranged to be locked by the armature 56 of the magnet 58. The contact stop 55 for
the angle arm of 48 is connected by the spring to the armature 56 also to one end of
the coil of 58, the other end of which is connected to the control contact 47 of the
first apparatus Z. In like manner the contact stop 52 of the angle lever 51 is
connected by the spring to the armature 57 and to the coil of 59 the other end of
which is connected to the control contact 46 of the first apparatus. The coil of 58
cannot communicate with earth unless the contact 44-46 is established in all the
apparatus. The operation of this arrangement is as follows:-
Assuming the operator to send current by wire 12 as described with reference to
Figures 8, 11, 12, this current will pass by 54, 53, through relay 51 which it will.
excite, then to spring 41 and contact 43 of the field coil 39, and the armature 37 of
the three apparatus, working the motors, but the armature 50 of the relay 51 being
attracted the contact 50--49 is broken, while contact is established of 50 with 52,
and thus the line wire 11 which should serve for control is cut off from the con-
tacts 40, and put in communication through the coil of 59 with the control
contacts 44, 46 of all the apparatus. When the movement of one apparatus is com-
pleted, the contact 41-43 is broken, cutting off current from the motor, and the
contact 40-42 is made. When this takes place in all the apparatus, the relay 51
becomes inactive, having current no longer. But simultaneously, as this is worked
from the same sleeve, the control commutator acts, breaking the contacts 45-47
and making the contacts 44-46. As soon as this occurs in all the apparatus the
circuit for the control current is closed, and this current causes the armature 57 to
be attracted setting free the arm of 50 which is caused by the spring to again
make contact with 49. At the operating station this control current produces also
by the wire 11 the effect described above, that is to say, the ascent of the bolt 19
allowing the lever 3 to complete its stroke to a position corresponding with that of
the apparatus.
To sum up, commutators for transmission 40, 42, 41, 43 are branched in parallel
on the circuit, whilst the commutators for control 44, 46, 45 and 47 are connected
in series, and the two line wires are commutated by the relays 49, 50, 52 and 53,
54, 55 in the lines for transmitting or for control as required. The commutators
40, 42, and 41, 43 normally commutate the transmitting or motor circuit, and act
also as control commutators when the apparatus is in a wrong condition. The position
shewn in Figure 13 for the receiving apparatus is in accord with that of the lever
shewn in Figure 12. Should one of the apparatus Z2 for instance, be in wrong
condition, then the contacts 45, 47 will be broken and contact of 44, 46 will be
made on the one hand, whilst contacts 41, 43 will be broken and contacts 40, 42 will
be made on the other hand. The contact 40, 42 gives communication from the
control wire 11 through the notor to earth, and this excites the control magnet 17
at the station which prevents the operating lever from being moved, and calls
the attention of the operator in the manner described.

page_text: The relays and electromagnets 51, 59, 48 and 58 may be arranged in the casing
of the first apparatus Z¹ or in a case near it, but it is to be noted that the two
supplementary wires required for control, extend only from the magnets to the last
apparatus 73, that is to say within the limits of the group of apparatus that are
simultaneously worked, whilst the line consists of the two wires 11 and 12 extending
from the operating station to the group, with a common return wire or earth.
I have said that the line wires might be exposed, but in this case they are subject
to confusion, fracture or contact with earth, whether they are for one apparatus or
several. In order that confusion or fracture of wires may not affect safety of traffic,
I employ the arrangement shewn in Figure 14 which constitutes an automatic per-
manent control of the electric condition of the wires and apparatus. It is based on
the use of two sets of differential circuits each controlling one wire of the line.
When the line is in normal condition the two branches of the circuit are in equalibrio.
Any confusion or fracture of the line wire destroys the equilibrium in one of the
branches, which results in the raising of the bolt and consequent stoppage of the
operating lever.
For this purpose the receiving apparatus is provided with two resistances say of
2000 ohms connecting earth to the springs 40 and 41 (Figure 14). Consequently
the total resistance of each circuit from the operating station is the saine, for the
wire 12 has the resistance of the line plus 2000 ohms, and the wire 11 has the resist-
ance of the line plus the reduced resistance of the field coils and the armature in
parallel with 2,000 ohms, it may be somewhat less than 30 ohms. At the operating
station place a relay 60 the coil of which consists of two equal wires wound
oppositely. I also arrange a supplementary commutator 62 having two contacts 63
and 64, this being worked uniformly with by an insulated connecting rod. Also.
the electromagnet 17 is coiled with two equal wires wound oppositely.
The contacts 63 and 64 are connected together and to the battery and the arm 62
is connected to the junction of the two relay coils 60 through a resistance 61 which
reduces the consumption. On the other hand the battery is connected to the junc-
tion of the two coils of the magnet 17 through a resistance 67 which reduces the.
consumption. One of the relay coils 60 is connected to the contacts 8 and 10 and
through them to the line wires; the other coil is connected to earth through a resist-
ance 73, equal to that of the line wire plus the reduced resistance previously des-
cribed. One of the coils of the magnet 17 is connected to the contact 14, and
through it to the line wire, the other is connected to earth through a resistance 68
equal to that of the line plus 2,000 ohins. From this arrangement it results that the
parts being as shewn in Figure 14 a system of continuous currents of equal intensity
is established in the two sets of coils of the relay 60 in opposite directions so that
the armature 65 is not attracted. A systein of continuous currents of equal intensity
and opposite direction is also established in the two coils of the magnet 17, and its
armature is not attracted. Should there be fracture of the wire 12, 41 there would
be no circuit in the corresponding coil, but the other coil of 17 would be traversed
by current, and the armature would be attracted. If instead of fracture of the
wire 12, 41, there were an earth contact, or if there were contact of 41 to 43 result-
ing from derangement of the apparatus, the current in the one coil would be more
intense than that in the other, causing excitement, attraction of the armature and
raising of the bolt.
Similar consequences affect the relay 60, that is to say, if there be fracture,
confusion or earth contact of the wire 11, 40, there would be a change of current in
the corresponding coil and consequent attraction of the armature 65, but in this case.
I apply the movement of this armature to make a contact 65, 66 which immediately
connects to earth one of the coils of the magnet 17 which acts on the bolt. The
cominutator 62 cuts the relay 60 off from the battery and prevents it from acting
during the commutation resulting from the movement of the operating lever. In
other words the differential electro magnet 17 controls the state of the controlling
line wire and translates into bolting of the lever the result of a defect in the control
:

page_text: wire. The differential relay 60 controls the state of the operating line wire causing
a bolting of the lever by the electro magnet 17 when the transmitting wire is
defective. In the two cases of bolting the lever as a direct or indirect conse-
quence of defect in the line, the attention of the operator is called by the
continued sounding of the bell 72, which is in a circuit including a battery, and the
contacts 70, 71, worked by the armature of the magnet 17; this circuit may also
comprise a galvanoscope as mentioned above.
This arrangement renders the working of an apparatus impossible when its line
is defective, and absolutely ensures safety, and further it announces a defect
immediately on its occurrence.
In order to apply the arrangement just described to a group of simultaneously
acting apparatus, I place the 2,000 ohms resistance between earth on the one hand
and the armatures 50 and 54 (Figure 13) on the other hand, that is to say, at the
ends of the line wires.
Obviously in calculating the resistances 66 and 73, new elements occur, namely,
the resistance of the relays 48 and 51 in reckoning the coils 68, and this same
resistance added to the reduced resistance of the motors in re-opening the
coil 73.
My invention lends itself easily to interlocking arrangements depending on electric
contacts. The locking bar 35 (Figure 8) is in that case utilized. to work the contacts,
the arrangement of which may be very various, but it may be understood, for
example, that two contacts adapted to the bar 35, might command the controlling
and operating circuits of another operating lever which could not be moved, unless
the former lever were in a certain position, so that if the first lever is not in the
required position, it opens the operating circuit and closes the controlling circuit of
the second lever and so prevents its movement.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim in respect of apparatus for electrically operating railway points and signals
is:-
1. Transmitting apparatus comprising a frame with notched circular edge, a lever
mounted thereon and provided with a double pawl and a stop stud, a cam with
notches and shoulders for the pawls, a commutator connected with certain play to
the lever, a reversing switch connected to the cam, an electro magnet and its
armature connected to a vertically sliding bolt provided with notch for passage of the
stop stud of the lever, also an electric signal of derangement substantially as
described with reference to Figures 8, 9, 10, 11 and 12 of the drawings.
2. Receiving apparatus comprising a reversible electric motor a wheel geared
thereto and carrying a crank pin with roller engaged in a slot partly curved and
partly straight of a lever connected to a point or signal rod, substantially as described
with reference to Figures 1, 6 and 7.
3. In combination with the receiving apparatus referred to in Claim 2, a cam and
lever connected to a point safety bar, substantially as described with reference
to Figures 2, 6 and 7.
4. In combination with the receiving apparatus the control commutator
constructed and operating substantially as described with reference to Figures 3, 4
and 5.
5. The modification of the control commutator substantially as described with
reference to Figure 6.
6. The combination of the transmitting apparatus, the receiving apparatus, the
control commutator with a source of electricity, a pair of line wires, and a return,
substantially as and for the purpose set forth.
7. For simultaneously operating several points or signals of a group, relays,
electro-magnets and suitable contacts, interposed between the line wires and the
earth or return connections for the several receiving apparatus of the group,
substantially as described with reference to Figure 13.

page_text: 8. For providing against derangement of the line wires the arrangement in
combination with them of the resistances double coils and relay substantially as
described with reference to Figure 14.
1
1000
ABEL & IMRAY,
Agents for the Applicant.