Improvements in Electric Signalling Apparatus.
Year: 1894

page_text: Date of Application, 17th July, 1894-Accepted, 13th Oct., 1894
COMPLETE SPECIFICATION,
[Communicated from abroad by THE STANDARD ELECTRIC SIGNAL COMPANY,
of Rochester, New York, United States of America.]
Improvements in Electric Signalling Apparatus.
I, CHARLES ARTHUR ALLISON, of 52 Chancery Lane, Loudon, in the County
of Middlesex, 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
ascertained in and by the following statement :-
This improvement relates to electric signalling apparatus, and consists in the
combination and arrangement of parts hereinafter described,-
In the drawings-
Fig. 1 is a plan showing the general system;
Fig. 2 is an enlarged face view of the differentiating apparatus with a portion of
its top broken away i
Fig. 3 is a plan of the relay ;
Fig. 4 is a perspective view of the electrical stop ;
Fig. 5 is a plan of one of the street boxes with a portion of its top removed;
Fig. 6 is a similar view of one of the sub-station or auxiliary boxes;
Fig. 7 is a cross section of one edge of the box shown in Fig. 5;
Fig. 8 is a horizontal section of the stop arrangement of the box shown in
Fig. 6;
In this system a central station or office is used in which are located the working
parts.
A indicates the relay, B the differentiating apparatus, C an engine house or fire.
department station, E a police or other station, and F an electro magnet for
operating a register at the central station, whereon is recorded the number of the
box from which the signal is sent. The relay A consists of two pairs of electro
magnets a, a, and a', a', two sets of uprights e, e, and e', e¹, two sets of swinging
armatures c, c', c³, and e³, c, c, located at opposite ends of the magnets, and two
upright contact posts b and b'. The armatures play between the magnets and the
posts.
The differentiating apparatus B, consists of a box provided with a conducting
base plate and an exterior face d, of insulating material. g is a time movement
or clockwork, and h an escapement connected therewith. i is an arm, forming a
circuit breaker attached to a shaft of the time movement extending out through
the insulated face, the arm resting across the face, but not in contact therewith.
The time movement gives motion to the arm and causes it to traverse over the face
of the apparatus, k, k, l, 1, and m are contact blocks forming electrodes set into
the insulated face, and n, n', are spring tongues forming conductors attached to the
arm and connected together, said tongues being insulated from the arm by a rubber
block o.
As the arm rotates the tongues come in successive contact with the
several conducting blocks and change the currents.
P, P, is an electro magnet, and 9 is a pivoted crank forming an armature which
operates in connection therewith. On the outer end of this crank is a pin q' which
passes through a slot of the top of the box and intercepts a pin r, on the under
side of the arm i, thereby holding said arm against rotation. When the
magnet p, p, is charged the armature is drawn back removing pin g' from the path
of pin and allowing the arm to rotate.
3, 3, is another electro magnet and t an armature pivoted at t' and provided with
an inclined lug t. The armature t is pressed forward by a spring u tightened by

page_text: a screw v. When the magnet is charged it overcomes the spring and draws the
armature back. w is an arm turning on a pivot w connected with the base, the
free end of the arm engaging with the inclined lug 2 of the armature. When in
this position the arm to rests in contact with a flat spring attached to an insulating
block y.
When the armature is drawn back by the magnet the arm w frees from
the spring and opens the circuit, and remains out of contact till arm w is struck by
a pin z on the shaft of the arm i which restores it to place by pressing it under
the lug t. The arm w is drawn from contact with spring x by a coiled spring j.
This arrangement is for communication with the fire department only.
The same arrangement is duplicated on the opposite sile of the apparatus,
consisting of magnets s¹, s', armature provided with inclined lug t, spring u¹,
screw, pivoted arm w³, contact spring attached to insulating block y', and
coiled spring, the whole operating to establish communication with the police or
other department.
The main circuit consists of two wires 1 and 2. said wires being provided,
respectively, with batteries G, H, or other sources of electricity. The terminals
of wire connect with the two electrodes k, k', on 'the face of the differentiating
apparatus B, and the terminals of wire 2 with the two sets of magnets a, a', of the
relay A. The main line is provided with suitable street boxes P, and auxiliary
boxes L, the latter connected with circuits extending through buildings and
provided with thermostats and manuals. By means of these boxes signals are sent
to the various destinations over the same main line.
Under normal conditions the main line circuit is closed, the magnets of the
relay A are charged, and the armatures of the relay are drawn toward the magnets.
But any opening of the main circuit releases the armatures, which are then drawn
toward the posts b., and the circuits at the central station are then ready to come
into operation. The circuits are as follows:-
A circuit extends from battery J, through wire 3 to armature c³, thence, (when
the main circuit has been broken and said armature is in contact with post b),
through post b, wire 4, the register magnet F, causing it to operate the registering
apparatus, wire 5, magnet p, p, wire 6, (touching the conducting block m), back to
battery J. The energizing of magnets p, p, draws back armature 9, removes
pin q from the path of pin r and releases the arm i and allows it to rotate.
Prior
to this time the tongues n, n', have remained in contact with the blocks k, k¹. They
now leave said blocks and pass to blocks and m.
7"
Another circuit extends from battery K to the fire department. This circuit is
from battery K through wire 7, upright e, armature c', wire 8, the magnet at the
fire station, and wire 9 back to battery K.
Auxiliary to circuit K is another circuit from battery K through wire 7, wire 10,
spring, arm, the pivot w' of said arm, through the metallic base of the
differentiating apparatus B, wire 11, wire 8, the magnet at the fire department, and
wire 9 back to battery K.
Another circuit extends from the central station to the police department, from
battery I through wire 12, upright e', armature e, wire 13, the magnet at the police
station, wire 14, back to battery I.
. Auxiliary to this last circuit is a circuit from battery I through wire 14, the
magnet at the police station, wires 13 and 15, spring a¹, arm w³, the pivot w, of
said arm, the base of the apparatus, wire 16, and wire 12 back to battery I.
The circuit K and its auxiliary just described are duplicates of the circuit I and
its auxiliary before described, one circuit connecting with the police department
and the other with the fire department.
The first action in opening and then closing the main circuit through wire 2 is
to temporarily close the local circuit J, and thus release the time mechanism of the
differentiating apparatus and allow the arm i to rotate. The movement of arm i
brings tongues n, n', in contact with the blocks l, m, thereby forming a new circuit,
from battery J through wire 3, ai mature c¹ (then in contact with the upright of the
relay magnet), wires 17 and 18, magnets 8, 8, wire 19, electrode 1, tongues n, n',

page_text: contact block m, wire 6 back to battery J. The charging of magnets 8, 8, draws
back armature t and releases arm to allowing it to separate from the spring, thus
breaking the circuit that previously existed by the contact of the arm with the
spring and extending through the base of the apparatus to wire 11.
The further progress of arm i causes tongue n to leave block 1, breaking the
circuit just described, and brings tongues n, n', in contact with blocks l, m, and forms
wires 17
a new circuit, from battery J through wire 3, armature c', upright e,
and 20, magnet s', s¹, wire 21, contact block 1, tongues n, n', block m, and wire 6
back to battery J. The energizing of magnet s', ', draws back armature t
releases the pivoted arm w² from spring thereby breaking the circuit that
previously existed leading from battery I through the base of the apparatus to
wire 16. This circuit, with its companion on the opposite side, are not re-established
until arms and to² are forced into contact with the armatures t and t², by the
pin z near the end of rotation of the arm i.
Under such conditions, with both circuits open, the circuit through the fire
department is from battery K through wire 7, upright e, armature c, c', (then drawn
back by the magnets a, a, and subject to any action of the relay), wire 8, the
magnet at the fire station, and wire 9 back to battery K. At the same time the
circuit through the police station is from battery I through wire 12, upright e',
armature, wire 13, the magnet at the police station, and wire 14 back to
battery I.
It will be seen that the register F, the magnets at the fire station C and the
police station E, are each, through the armatures at the relay rendered susceptible
to the operation of the relay, and that the circuits are changed to send the signal
to one department or the other through the instrumentality of the differentiating
apparatus. By the use of this differentiating apparatus all signals which come to
the central station are recorded there and despatched to the proper destination,
such as the fire department or the police department, without one interfering with
the other.
as
Connected with the main circuit are auxiliary or sub-station boxes L, (which
form the subject of my present invention) with lateral loops or circuits 23 extending
from the main line through buildings and provided with thermostats and manual
boxes, also street fire and police boxes P for sounding alarms at the various
stations. These boxes have many parts in common with the differentiating
apparatus. They have arms 1, 3, and time movements g¹, g³. Each of the
street boxes P have contact rims and blocks a, a, a, a, set into the insulated
face of the box, the outer rim a having a break just in advance of the
starting point of the arm and the inner blocks a³, a³, having a break
shown in Fig. 5. Each of the auxiliary or sub-station boxes L has also contact
rims and blocks a, a", a¹³, a¹³, a, ais, a¹, a 17, 18, 41, a20, arranged in five
concentric rings on the insulated face of the instrument, with breaks between
them, as shown in the face view Fig. 6. Each of the arms of the strect boxes P
bas two outer spring tongues n³, nº, connected together and insulated from the
arm, and an inner separate spring tongue n³, in electrical contact with the arm.
These three tongues rest in line with the three concentric rims of the contact
blocks so as to sweep over them. In like manner the arm of boxes L has two
pairs of tougues nº, n¹º, and n¹, n¹², the tongues of each pair connected together and
insulated from the arm, and a single intermediate tongue n electrically connected
with the arm.
These several tongues rest over and come in contact with the five
Bets of conducting rims and blocks set into the face of boxes L.
The boxes L and P have respectively electro-magnets p², p², similar to the
magnets p, p, of the differentiating instrument B; also pivoted armatures ƒª,ƒª,
provided with inclined lugs ƒ³, ƒ³, also pivoted crank arms ², *, similar to the
crank arm in the differentiating instrument, and carrying stop pins at their outer
ends for restraining the swinging arms. The energizing of said magnets removes
the stop pins and repasses the arms in the same manner as in the differentiating
instrument. In addition to these features the crank arm h' of box P has an

page_text: intermediate arm which projects inward in such position as to be struck by the
pin', on the shaft of the arin shortly after starting, to re-set the crank arm with
the armature. Each of the boxes L, P, is also provided with a wheel o³ on the shaft
of the arm, against which bears a spring 2 pressed up by a screw ², the object
of which is to apply sufficient friction to the gearing of the time mechanism to
prevent back action. The exterior rims of the boxes also have circuit breaking
notches,, arranged in two series in order to indicate numbers for sounding
alarms over the main line.
In addition to these devices the boxes P are started in operation manually by
pressing the finger on a knob t, Fig. 7, which removes a pin from contact with the
end of the arm and releases the latter. The finger knob stands a little in the
rear of the stop pin on the crank arm * so that when released by pressing the knob
the arm has a small degree of rotary movement and then is stopped by striking the
pin on the crank arm. The boxes L are each provided with two finger knobs t¹³, t¹³,
similar to the knobs on the street boxes, by which means the arm has two stops
before reaching the restraining pin on the crank arm.
It is the design that should a signal be in the act of transmission from a box L
to the central station and should a street box P be operated while said box L is in
operation, the signal given from box L will not be interfered with, but at the end
of the operation of the said box L then the street-box P which has in the meantime
remained in suspension, will complete its operation automatically.
It is also the design that should a street box P be in operation and a manual
box or a thermostat in a building be operated, such operation will not start the
box L but when the street box has completed its operation then an additional
operation of a manual box or thermostat will operate the box L.
It is also the design that should a manual box or a thermostat in the circuit
leading to the buildings protected by box L be operated, no other manual box or
thermostat in the same circuit will effect the operation of the box L started by the
first manual box or thermostat.
Another function of the box L is that immediately after its time movement
begins to operate, it closes a circuit and charges the magnet of the building gong
and causes said gong to ring till its time movement has run down, thus alarming
the inmates of the building. Immediately upon the operation of any one of the
signal boxes the circuit on wire 1 is immediately destroyed and is not restored again
under any circumstances till said signal box has ceased to operate and has
performed its function, at which time the current through wire 1 is restored again
and remains in that condition while the system is normal. The box L being
normal the current is from battery H. through wire 1, wire 22, contact block a
tongues no, no, contact block a¹8, wire 23 forming the circuit through the building,
block a, tongues 12, n¹, block a¹, wire 24 and wire 1. back to battery H. To
complete the circuit the tongues n, n', of the differentiating instrument must be in
contact with the blocks k, k'. If from any reason wire 23 is broken, the current
of wire 1 being shut out of the building will seek another escape and will pass
through a shunt circuit as follows: From battery H to wire 1, wire 25, resistance
coil 26, wire 27, electro-magnet p³, wire 34, contact block a", tongues n", n",
contact block a", wire 24, and wire 1 back to battery.
The current through wire 2 is from battery G to the base of the instrument
at thence through the arm i, tongue n", contact block a", wire 28, and wire 2
back to battery G.
In case wire 23 of the building line is broken the magnet p² is energized, thus
attracting the armature f* withdrawing the stop pin that restrains the arm i¹ and
the arm then commences to traverse the instrument. For a short period after the
commencement of the movement of the arn the currents in both wires 1 and 2
are absolutely broken and remain so until the arm in its progress brings tongue n'
in contact with block a¹6, tongue in contact with block a" and tongue no in
contact with block a¹8. At this point it is to be determined whether the circuit in
he wire 23 has been interrupted by a signal or has been permanently destroyed as

page_text: in the case of a broken wire In case it has been interrupted the current through
wire 2 is as follows:- From battery G through wire 2 to base of the instrument
at z', arm ¹, tongue n", block a¹ with which the tongue is then in contact, wire 29,
wire 23, contact block a18, tongues 10, P, contact block a", wire 31, wire 2, back
to battery. In case wire 23 is broken there is no current until the further progress
of the arm has brought tongues n", n, in contact with the rings alo, and all In
the case of the immediate restoring of wire 23 the further progress of the swinging
arm brings tongue n in contact with block a". The current is then from
battery G, through wire 2 to base of the instrument at 2, arm, tongue n¹³,
block a", wire 30, wire 23, block a¹8, tongues 10 and no, block a" with which no is
then in contact, wire 31, wire 2, back to battery. This current will energize any
electro receptive devices placed in wire 30.
n'
The further progress of the arm brings tongues n", n¹, in contact with the
rings a, a¹. From this time on during the movement of the arm the circuit in
the wire is the same whether the wire 23 in the building has been permanently
broken or simply interrupted by a signal. In either case the sigual will be
transmitted to the central station. But in case the circuit has been interrupted by
a signal the signal will be transmitted to the central station and the fire and police
departments, while if permanently broken it will be transmitted to the central
station only.
The condition now is that the tongues n", n¹, are in contact with the rings alo, a¹¹,
respectively, and progressing around the instrument. The circuit of wire 2 is now
as follows: From battery G through wire 2, branch wire (Fig. 6) 61, ring a",
tongues, n, ring a, wire 32, and wire 2 back to battery. Ring a", is notched
on its face in two series with the numbers indicating the box as shown at v³. As
the arm progresses over the face of the instrument tongue n¹ engages said
notches and alternately opens and closes the circuit thus signalling the number of
the box at the central station over wire 2.
The further progress of the swinging arm brings tongues no, no, in contact with
blocks a0, a18, tongue n¹ in contact with block a; and tongue n¹ in contact with
block a¹³.
:
The circuit now in wire 1, which is restored is from battery H to wire 1, wire 33,
block a, tongues n", n¹¹, block a¹, wire 24, wire 1 back to battery. The current
through wire 2 which has been inaintained, is from battery G through wire 2, the
base of the instrument at 2, arm i¹, tongue n", block a", wire 28, wire 2 back to
battery. There the swinging arm is stopped by the first finger knob t until the
lineman, having repaired the broken wire 23 puts the same in condition for further
service. The finger knobs for stopping. the swinging arm are simply to enable
testing to be made without sounding an alarm at the central station. After such
testing has been made the swinging arm is released from the knobs and allowed to
move forward to the electrical stop on the end of the cranked arm, when it is ready
to be released by the electrical action as before described.
Referring now to the street boxes P, in the normal condition the swinging arm
is held in a stationary position by the finger knob t. By pressing on this knob
the arm is released and moves forward till it strikes the stop pin on the end of
crank arm and is held there till the magnet 7 is charged drawing back the
armature which holds it. In the normal condition tongue n rests on block a
and tongues, no, on the rings a, a'. The current in wire 1 is from battery H to
the base of the instrument at a, through said base, arm i³, tougue nº, block a³,
wire 34, wire 1, back to battery. The current through wire 2 is from battery G
through ring a, tongues no, no, ring a', and wire 2 back to battery.
The movement of the swinging arm from the finger knob to the electrical
holding pin removes tongue n³ from block as and brings it in contact with block a',
which forms a new circuit in wire 1, from battery H through wire 1, base of the
instrument at , swinging arm i³, tongue no, block a³, wire 36, magnet p', wire 37,
wire 34, and wire 1 back to battery. The current through wire 2 remains the same
as before, since the tongues n', no, have not left the rings a, a'. The charging of
;

page_text: magnet p attracts the armature f*, releases crank arm h, removes the stop pin in
advance of the swinging arm and allows said arm to operate. The further
progress of swinging arm brings tongue no over the break in the outer ring a³,
thereby breaking the circuit in wire 2 leading to the relay at the central station.
This starts the differentiating instrument at the central station. The further
progress of the swinging arm brings tongues no, no, again in contact with
rings a, a, restoring the circuit through wire 2. As the arm progresses the
tongue n passes over a series of notches in the rim, alternately opening and
closing the circuit and signalling the number of the box at the central station, and
through that to the fire department. Now while this particular box is in operation
as described, should some other box on the main line be started by releasing its
finger knob holding the swinging arm, said arm of the second box could advance
no farther than the stop pin controlled by the electro-magnet, and the current
through wire 1 being destroyed said electro-magnet would not be charged and no
action could take place. It would so remain until the first box, having completed
its signal and restored the current in wire 1, energized the magnet in the second
box, when the stop pin in the second box would be withdrawn allowing the second
box to give its signal following the other. This is done automatically.
The police boxes are of the same construction as the fire boxes except that the
break at bis of greater length than in the fire boxes. Fig. 5 shows one of the
police boxes. This break in the police boxes is of such length that the current in
wire 2 having been broken, and the differentiating instrument at the central station
having been started, the current in wire will remain broken until such time as the
swinging arm of the differentiating apparatus shall have passed the point where
the fire department circuit is placed in position to receive signals from wire 2. In
such case the signals given at the police boxes are sent to the central station and
from there to the police station without being sent into the fire department.
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 is :-
1st. In an electric signalling apparatus, the combination, with a main circuit
composed of two wires, and a lateral circuit provided with thermostats and manuals,
either or both, of a box connected with said wires, provided with an insulated face,
a set of conducting blocks connected therewith, a movable arm provided with
contact points resting in line with the conducting blocks and capable of changing
the circuits by moving from une block to another, and suitable electrical
connections connected with said blocks, as shown and described and for the
specified.
purpose
2nd. In an electric signalling apparatus, the combination of a box, a movable
arm resting over the face of the box, two manual stops, one in advance of the
other, for restraining the movable arm, and an electrical stop succeeding the manual
stops for restraining the arm, said electrical stop being controlled by an electro-
magnet, as specified.
3rd. The combination, with the movable arm, of two plungers provided with
outstanding pins forming stops to the arm, one succeeding the other, and springs
for pressing the plunger upward, as described.
Dated this 17th day of July 1801
ALLISON BROS.,
Agents for the Applicant.