A System of Sending and Receiving. Fire or other Special Signals .Over Telephone Lines.
Year: 1892

page_text: Date of Application, 29th Feb., 1892
Complete Specification Left, 22nd Nov., 1892-Accepted, 29th Mar., 1893
PROVISIONAL SPECIFÍCATION.
A System of Sending and Receiving. Fire or other Special Signals
.Over Telephone Lines.
-
FRANCIS ELLIOTT STUART Fire Brigade Electrician & Expert, Volthurst.
Twickenham, do hereby declare the nature of this invention to be as follows:
In an ordinary telephone circuit between fire stations, with electric call bells,..I:
place a second contact-maker at each end, and also a polarized relay, and local bell
and indicator circuit; when the ordinary push is used, it calls attention to the
telephone at the other end of the circuit, but when the second contact maker of:
push is used, it reverses the relative positions of the poles of the battery on the
line, and return wires or on the line & earth wires, and the current operates the
polarized. relay in the reverse direction, at the other end of the circuit' which
polarized relay being reversed, connects a second and local circuit, which rings:
a different bell, and if necessary drops an indicator, thus indicating a fire or
special call.
1
I specially propose to use this system where several outlying fire stations are
connected to a central station by telephone.
: 1
The central station being provided with an annunciator, to shew from which
outlying station the call has been received, and being provided with a row of contact
makers, corresponding to the outlying stations. Upon any of these being pressed,
the big fire bell will ring at the outlying station, and thus indicate they are to turn
out for a fire.
Dated this. Twenty-seventh day of February 1892
COMPLETE SPECIFICATION.
1°
A System of Sending and Receiving Fire or other Special Signals
Over Telephone Lines:
FRANCIS ELLIOTT STUART, Fire Brigade Electrician & Expert. Volthurst
Twickenham 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 :-
According to my invention: I am able to send special signals for fire purposes,
over existing telephone lines; either of metallic circuit, or single wire and earth
return independently of the ordinary electric bells used for calling attention at
either end, and which special signals consist of the ringing of a separate bell from.
a separate contact-maker, at either end of the line; which separate contact maker
rings the corresponding signal bell at the other end.
In practice specially propose to use this system between outlying fire stations
and their district station; and for this purpose, where several stations are connected
to a district station by telephone I propose to use at the central, or district station
an indicator, to shew which outlying station has signalled, and an electric bell to
call attention, and for the sake of convenience, I combine with this indicator, an
ordinary telephone annunciator, with the usual plugs, and plug holes, and also
contact makers, or morse-keys, for sending the fire signal to the various outlying
stations.
The whole apparatus is so arranged, so that any number of fire stations can be
turned out in the least possible time, from the call arriving at the. first station,

page_text: and without in any way interfering with the telephone speaking an
arrangements.
And for this purpose. I provide at each of the outlying fire stations,
or part of the following apparatus, in addition to the ordinary telephone
battery:
A double contact polarized relay.
A special signalling key.
A specially constructed electric bell.
As sometimes telephones are connected together with double wires,
are more commonly called "metallic circuits ; and as at other times
wire is used, the earth forming the return, I utilize in the case of metalli
one of the line wires and an earth return, for my signalling, and in th
there being only one wire and an earth return, I use a polarized relay.
In order that my apparatus may be properly understood, I will now p
describe the same with reference to the accompanying sheets of drawings
I may add that the same letter denotes the same parts in all the fig
for the sake of convenience, I have drawn in detail the interior connec
Gower bell telephone, so that the connections of the system can be mo
traced..
.
In Sheet No. 1. I shew a complete telephone and fire signalling set of.ins
connected together for use with a polarized relay.
Fig. 1 shews the internal connections of a Gower-bell telephone.
Fig. 2 is the ordinary telephone bell.
Fig. 3 is the microphone.
Fig. 4 is the fire signal bell.
Fig. 5 is the polarized relay.
Fig. 7 is the triple signal key.
Fig. 8 is the battery.
!
The numbers are the numbers of the terminals of each separate figure.
In Fig. 4.
a, a, are the coils of the signal,bell.
b, is the spring on armature.
c, is the adjustable contact pillar.
d, is the upper contact arm..
e, is the upper contact stud.
f, is the lower contact arm.
9, is the lower contact stud.
h, is the lever pivotted at h¹.
i, is a cord to reset lever with..
j, is the armature.
In Figure 5.
s, and s², are the contacts on each side of the polarized relay.
t, is the armature with contact at.t..
In Figure 7.
j, is the main arm.
k, is the "off" contact of the main arm.
1, and m, are the side arms.
n, and o, are the back contacts of the side arms.
r, and g, are the front contacts of the side arms.
p, is the middle back contact stud.
In. Figure 1.
A, is the induction coil.
B, is the push.
C, is the lever.of back contact push.
E, is the telephone receiver.
F, and G, are the hook switch-arms..
The working of the apparatus,may be thus briefly described.

page_text: Supposing that two stations A, & B, have each a complete apparatus as shown
in the accompanying drawing Sheet 1.
On pressing the telephone button B Fig. 1 in station A, the telephone bell Fig. 2
rings in station B; and vice versa.
To obtain this end I will now trace through the connections.
⚫ On pressing telephone push B Fig. 1; the enrrent flows from the zinc pole of
the battery Fig. 8, to Fig. 7 terminal 6, contact arm m, front contact 7, terminal 2,
to Fig. 1, terminal 7, to back contact of push-B, through push arm C to terminal 4,
to line wire, and from the carbon pole of the battery Fig. 8, to Fig. 7, terminal 1,
contact arm 1, front contact r, terminal 4, to Fig. 1, terminal 5, to return wire.
And is received into the distant relay from line wire Fig. 1, terminal 4, to arm C,
to lower contact, to switch arm F, to
"on
contact, to terminal 1, to Fig..7,
terminal 5, to main arm j, to terminal 3, to Fig. 5, terminal 2, through relay to
terminal 4, to Fig. 1, terminal 5, to return wire.
Thus actuating the armature of the polarized relay Fig. 5, to the left, against
the contact studs s², and therefore ringing the local telephone bell Fig. 2.
I will now proceed to trace through the fire signal circuits on the same sheet'
of drawings.
to
On depressing the fire signal key j, Fig. 7, the current flows from the zinc pole
of the battery Fig. 8 to Fig. 7 terminal 6, to arm m, to back contact o, out at
terminal 4, to Fig. 1, terminal 5, to return wire and from the carbon pole of the
battery Fig. 8, to Fig. 7, terminal 1, to arm 1, to back contact n, to front'
contact, to main arm j, to terminal 5 to Fig. 1, terminal 1, to switch arm F,
back contact lever C, to terminal 4 to line wire. And is received into distant relay
Fig. 5, from line and return wires as before shewn, but being a reverse current
it actuates the armature t the reverse way, causing it to make a contact with the
stud s', thus joining up the local circuit of the fire signal bell Fig. 4.
The fire signal bell, Sheet 1, Fig. 4, is an ordinary continuous ringing electric.
bell, with an additional spring and contact, and is actuated in the usual way by
means of the lever h, when set with the cord i, catching against the armature j
and which when released by current in the coils a, a, is pulled back by a spiral
spring, allowing the contact spring d, to make contact with the stud e, (thus
joining up its own continuous action); and also allowing the spring to make
contact with the stud ; which when making contact operates other and various
local circuits, but specially the electric bell circuits to the mens rooms in the fire
station..
The fire signal key, Fig. 7, here consists of a triple Morse key, which when
operated, takes three separate contacts off three contact plates, and allows them
each individually to make contact with three other separate back contact plates.
The two outside arms l, and m, are connected to the poles of the battery, and
indirectly make contact with the two line wires, when operated they reverse the
connections between the battery and the two line wires to which they are normally.
connected.
The centre arm J normally connects one of the line wires to the relay, when
operated it puts said line wire direct to battery.
The telephone in this connection is used in the ordinary way.
I will now describe the electrical connections, and apparatus where metallic
circuits are used for the telephone service, and for this purpose in Sheet 2 of the
drawings, the following letters have been added and altered.
In Fig. 1
D is an ordinary relay, for joining up the local telephone bell circuit.
In Fig. 4
is a contact spring acting as the centre arm of an automatic Morse key.
In Fig. 7,
8, 5, s, are the three contact pieces of an "on" and "off" switch, for use in a
local and independent circuit.
t, t, is a metal cross bar, fixed to but insulated from, the lever arm j.

page_text: .
are two contact studs.
, is the front contact stud, of the main lever arm j.
Supposing that two stations A & B, have each a complete apparatus, as
shewn in the accompanying drawings Sheet 2.
On pressing the telephone button B, Fig. 1, 'in station A, the telephone bell
Fig. 2 rings in station B, and vice-versa.
On pressing the telephone push B, Fig. 1, the current, flows from the zine
pole of the battery Fig. 8, to Fig. 1, terminal 7, through the top stud, and
ringing button C to terminal 4, to line wire and from the carbon pole of the
battery, Fig. 8, to Fig. 1, terminal 5, to Fig. 7, terminal 3, to front stud a through
arm to terminal 5 to return wire, and is received into the distant station B,
relay D, Fig. 1 from line wire to terminal 4, to push arm C, to lever F, through
relay D, to terminal 1, to terminal 3, to switch. arm G, to terminal 5, to Fig. 7.
terminal 3, to contact stud a, to arm, to terminal 5, to return, wire. Thus
actuating the relay D, Fig. 1, which joins up the local telephone bell circuit.
"I will now, proceed to trace. through the fire signal circuits on the same sheet
of drawings.
On pressing the fire signal key J, Fig. 7, station A, a current is sent over
the line which rings the corresponding bell Fig. 4 in station B, and vice-versa.
On pressing the lever, Fig. 7, a current is sent from the signal battery
Fig. 9, (one pole .of which is connected to earth,) to Fig. 7, terminal 1, to back.
contact, to arm, to terminal 5, to return wire, and is received into the
station B, on the return wire Fig. 7. terminal 5, through arm j, front contact a to
terminal 3, to Fig. 1, terminal 5, to arm G, to terminal 3 to Fig. 7, terminal 2,
studs W, W, and arm t, t, to terminal 4, to Fig. 4, to terminal 4, through
coils a, a, through frame of bell, spring b, contact stud c, to spring 7, to spring d
to terminal 5, to earth, thus completing the fire signal circuit.
The fire signal bell, Sheet 2 Fig. 4, is an ordinary continuous ringing electric
bell, with an automatic Morse key, operated by the attraction of the armature j,
against the coils a, a, allowing the lever h, working on its axis , to fly back:
from its position of rest on the armature j, thereby releasing the spring (or main
arm of the automatic Morse key) r, from the contact spring d, and allowing it to
make contact with the stud e, which action switches the connection of the coils off
the earth contact, and puts it on to the local battery Fig. 8.
The connection of this action is as follows, the lever h, being released, the
current leaves the zinc pole of the battery Fig. 8, to terminal 7 Fig. 1, to
terminal 3 Fig. 4, contact stud e, spring, stud cspring b, framework of hell,
coils a, a, terminal 4, to Fig. 7, terminal 4, studs w, w, and bar t, t, terminal 2,
to Fig. 1, terminal 3, to contact arm G, to terminal 5 to battery, carbon pole,
Fig. 8.
In addition to this automatic Morse key, there is an additional and independent
contact made by the same lever h, pressing the spring, against the stud
9, and
thus closing the local circuits as explained in the description of Sheet 1 of the
drawings.
Both of these two actions are reset by pulling the cord i, attached to lever h.
The special fire signal key, Fig. 7, is an ordinary Morse key, with the main
arm j, at its normal position resting against the contact a, and when operated
against the contact, in addition to this there is added on the arm j, but although
fixed to it, insulated from it, the cross arm t, t, and which at its normal position
rests on the arms or studs w, w, thus allowing a current to pass from terininal 2
to terminal 4 when operated this connection is broken.
The action of the Morse key is as follows, on pressing the lever j, the return
wire of the telephone, (used as the line wire, in the signalling,) is taken off the
telephone and put on to the signalling battery direct, at the same time the local
signal bell Fig. 4 is disconnected by means of the arm t, t, being raised off the
studs, w. The " on and off" switch shewn in Fig. 7 letters, is used for
switching the local house bell circuit on and off the signal bell, for purposes of testing.
39

page_text: When the tubes on the Gower bell telephone are removed for the purpose of
speaking, the earth wire (which if connected would cause induction in the
instruments) attached to terminal 5 Fig. 4; through Fig. 4 and out at terminal 4,
to Fig. 7, in at terminal 4 and out at terminal 2, to Fig. 1, terminal 3 and thence
to the switch arm G, is removed from the speaking circuit, by the telephone
lever arm G breaking with its front contact stud.
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 1
claim is-
1. The combination of an ordinary telephone circuit between fire stations, with
ordinary ringing bells; and a second and distinct bell operated from a separate
contact maker, but working on the existing telephone line wires or wire, or with
an earth return in conjunction with the line wire, or line wires, substantially as
and for the purpose hereinbefore described.
2. The combination of an automatic Morse key action, with or without a second
contact operated by an electric bell, as herein described, 'as and for the purpose
set forth.
3. The means employed for automatically ringing the existing house bells at a
fire station, from another and distant fire station.
4. The means employed for disconnecting the earth contact or connection, from
the speaking circuit.
5. The combination with each other, of the various mechanical parts and
electrical connections, described above and illustrated in the accompanying
drawings.
Dated this Twenty-first day of November 1892.
FRANCIS ELLIOTT STUART.