A New or Improved System of Communicating Visible Signals and Establishing Electrical and Telephonic Connection between Central, Town, and District Stations, and Mechanism and Appliances connected therewith.
Year: 1891

page_text: Date of Application, 19th Nov., 1891
Complete Specification Left, 19th Aug., 1892-Accepted, 1st Oct., 1891
PROVISIONAL SPECIFICATION.
A New or Improved System of Communicating Visible Signals and
Establishing Electrical and Telephonic Connection between
Central, Town, and District Stations, and Mechanism and
Appliances connected therewith.
1. CHARLES EGGAR, of 46 College Street, Glasgow, Lanarkshire, Engineer, do
hereby declare the nature of my invention to be as follows:-
This invention has reference to a new or improved general system of communicating
visible signals, and establishing electrical and telephonic connection between central
or police stations in towns and distant local or suburban district stations or cabins,
and mechanism and appliances connected therewith.
By these improvements electrical connection will or can be established between
a central or police main station or stations in a town, and any of a series of local or
suburban cabins or district stations within the municipal boundary, to actuate and
show a shaded or coloured light, semaphore, or other signal to attract the attention
of the constable or policeman on or near that "beat or local district, to let him
know that he is to receive instructions by telephone in this cabin from the central
station, and also enable any constable to communicate with the central station when
he desires. The constable after entering this district cabin by opening the door
with a special key, hereinafter termed the constable's key, will automatically
make electrical connection with the central station through the telephone, and will
first lower the shade or light signal, and then communicate with ordinary trans-
mitting and receiving telephonic instruments fitted within the cabin, with the central
station in electrical connection therewith, and receive his instructions from same
If the constable should require the assistance of an additional man, he can, while in
the cabin, raise the shade or light signal to draw the attention of the nearest
constable in the district. The improvements also comprise the use of an additional
and separate special key, which would be supplied to citizens, householders, or
separate officers in the district, and hereinafter termed the "citizen's key," and
which would or may have the users name or number on it, whereby by inserting
this in the same lock they may open the cabin doors, but cannot re-lock the door
or withdraw their keys again until released by the inserting of the separate key of
a constable in the inside or opposite key-hole of the lock. The opening of the
cabin door by the citizen's key will also by a mechanical connection from the lock
automatically raise the signal shade or light to attract the attention of a district
constable to the cabin, and the citizen after having opened the door. can com-
municate by the telephonic instruments and electrical connections inside, with the
central station to request police assistance, call up fire brigade, or give or receive.
other instructions.
:-
These improvements would be carried into practice under one arrangement all
as follows The signal cabins would consist of round, hexagonal, or other shaped
boxes or buildings, preferably built of metal plates, with overlapping layers of
glass above, and with a gas lamp overhead outside supported on brackets from the
cabin, or on a post or standard, while an opening and closing door for entrance to
the cabin would be fitted at one side. The gas would be supplied from duplex
vertical pipes, and a transverse horizontal connecting pipe and a pipe leading from
it to the lamp burner and having a tap on one gas pipe for being raised or lowered
in pressure or light by the police or ordinary street lamp attendants and having
the other as a byepass valve to be automatically operated by the raising of the
shade signal as hereinafter described. Electric line wires would be carried from
the central station, either on poles and insulated supports overhead or in channels

page_text: underground much in the usual manner in which telephone wires are carried, and
electrical circuit connection made with each cabin. The main line wire would be
connected to a terminal on a plate at the top of the door of each cabin, where other
two terminals would also be placed, one on each side, and parallel insulated wires
would be led from each of these terminals round channels or spaces formed on the
inside surface of the cabin door and each connected to separate switches, preferably
spring blades or plates, near the door lock. Two contact plates would be fitted on
the inner end of the sliding bolt of the lock preferably of an shape, and one of
the side spring switches would be in contact with each plate respectively while the
centre or current line spring switch can be placed in electrical contact with either
plate acccording as the bolt is locked or unlocked. The two, side wires leading
from the spring switches to the terminals at top of door, would further lead
from these terminals respectively to supply electric currents to operate an electro
magnet actuating the lamp shade lever, and to supply current to establisli cléctric
connection with the telephonic instruments placed within the cabin as hereinafter
described. The lamp coloured shade which is preferably of an annular shape to
surround the light is attached to vertical guide rods, and automatically pulled up
into and held in the raised exposed position by weights attached to cords or chains
passing round guide pulleys, as soon as released from the catch on the short vertical
arm of a bell crank lever preferably fulcrumed on the transverse gas pipe. The
longer horizontal arm of this lever has a spring catch armature lever connected
with it which is disengaged by the electro-magnet when a current is sent.
through it, to release the catch arm of lever and permit signal shade of lamp
to rise.
The mode of operation is as follows:-When communication is desired to be
established between the officers at the central station and one of the signal cabins
they turn in the ordinary manner the telephone crank handle in connection with
that cabin, and by so doing send a current through main line wire and its spring
switch on cabin door on to terminal contact plate of signal wire switch (with which
when the cabin door is locked it is always in contact) and the current is thus sent
through the signal wire to the coils of the electro-magnet, which attracts the
armature and frees the catch on the end of the long horizontal arm of bell crank
lever and releases the catch on the other or vertical arm of this lever to free the
contact with signal shade, so that the weights will raise it. to cover the light, and
at same time in passing the byepass valve on gas pipe will turn it round to admit
full pressure of gas in lamp, and thus signal to the nearest constable that his
services are required in the cabin. When the constable opens the cabin door by
inserting and turning his key in the lock, this action slides the locking bolt along
and shifts the line wire switch from the electric contact plate of signal wire to the
corresponding plate of telephone wire, which enable telephonic communication to
be established between this cabin and the central station. The constable first
however after entering the cabin would draw down a hand cord attached to lamp
shade to bring down the latter to its lowest position, where it would be auto-
matically held by the catch connection on the bellcrank lever, and by this means
avoid another constable in the district being taken off his duty to attend to the
signal. The constable can now receive instructions from the central station by
the receiving and transmitting telephonic instruments in the ordinary manner. Or
if he entered the cabin without receiving a signal he can transmit requests or
instructions to the central station in this manner, without showing the shade or
visible signal. If the constable should desire to signal for an additional constable
in the district, while he is speaking at telephone, he can raise the lamp shade to do
so by pulling a cord attached to the arm of a mechanical switch lever mounted
above the cabin door, which switch lever is connected by another cord wire or
connecting rod to the catch or armature lever fo free the long arm of the shade
bellerank lever, and by this means the other catch arm of this latter lever is
released and shade will automatically travel up to its signalling position round
lamp. When the constable is finished and leaves the.cabin, the movement of the

page_text: sliding bolt in locking the door will automatically shift the switch of main line wire
from the telephonic line contact switch plate on to the signal line switch plate ready
to receive the next signal.
When a party possessed of a citizen's key desires to enter signal cabin, the
action of inserting and turning this key in lock shifts the line wire switch on to
contact plate of telephone wire which enables the citizen or person to com-
municate by telephone inside cabin with central station, and the same action of
turning citizen key in lock raises a vertical rod sliding in guides on the inside
surface of the door with contacts at its upper end which operates the before
mentioned mechanical switch lever above door to release the long arm of shade
lever and release the catch to free the lamp shade which will automatically rise to
its signalling position to communicate to the nearest constable that his presence is
also required at signal cabin to take instructions. And the same action of turning
the citizen's key to "shoot" or slide locking bolt in opening cabin door, further
locks said key within the lock, and prevents the door being re-locked or the key
being withdrawn until it is released by a constable's key being inserted in a special
key hole of lock inside door, to allow citizen's key to shift or adjust the sliding
bolt. The improvements in the lock to enable the two keys to actuate it as
described, consists in having two tumbler levers, both working and taking on to
one lateral catch on the bolt to fix the bolt in its outward locked or inward
unlocked position. The constable's key is made to lift both tumbler locking
levers and unlock or lock the bolt substantially in an ordinary manner; but
the V part of the bolt is formed with a projection on its inner side half the depth
or thickness of bolt, which the constable's key passes and throws the bolt fully open
so as to pass and be removable. But the citizen's key is made with a projection
at this projecting part of the bolt so as to throw and lock the bolt after raising the
locking or tumbler levers, and be itself locked in the inner position of the bolt, by
one of the tumbler levers which it allows to drop by one of its notches, while
holding up the other tumbler lever which raises and keeps up the vertical switch
operating rod. The key will remain in this locked position until released by a
constable's key inserted in a hole on the inside of the lock fitted with a special ward
plate exactly fitting the constable's key, which by a special projection on the said
locking tumbler raises it, and so allows the citizen's key to be turned and withdrawn,
at the same time lowering the vertical switch rod, while a citizens key cannot pass
the ward plate on the inside of door lock.
Dated the 18th November 1891.
W. K. M. THOMSON & CO.,
96, Buchanan Street, Glasgow, Agents.
COMPLETE SPECIFICATION.
A New or Improved System of Communicating Visible Signals and
Establishing Electrical and Telephonic Connection between
Central, Town, and District Stations, and Mechanism and
Appliances connected therewith.
I, CHARLES EGGAR, of 46 College Street, Glasgow, Lanarkshire, Engineer,
do hereby declare the nature of my invention, and in what manner the same is to
be performed to be particularly described and ascertained in and by the following
statement in writing, that is to say :-
:--
This invention has reference to a new or improved general system of com-
municating visible signals, and establishing electrical and telephonical connection
between central or police stations in towns and distant local or suburban district
stations or cabins, and mechanism and appliances connected therewith.
By these improvements electrical connection will or can be established between
a central or main police station or stations in a town, and any of a series of local
or suburban cabins or district stations within the municipal boundary, to asturie

page_text: and show a shaded or coloured light, semaphore, or other signal to attract the
attention of the constable or policeman on or near that "beat or local district, to
let him know that he is to receive instructions by telephone in this cabin from the
central station, and also enable any constable to communicate with the central
station when he desires. The constable after entering this district cabin by
opening the door with a special key, hereinafter termed the "constable's key,"
will automatically make electrical connection with the central station through the
telephone, and will first lower the shade or light signal, and then communicate
with ordinary transmitting and receiving telephonic instruments fitted within the
cabin, with the central station in electrical connection therewith, and receive his
instructions from same. If the constable should require the assistance of an
additional man, he can, while in the cabin, raise the shade or light signal to draw
the attention of the nearest constable in the district. The improvements also
comprise the use of an additional and separate special key, which would be
supplied to citizens, householders, or separate officers in the district, and hereinafter
termed the citizens key," and which would or may have the users name or
number on it, whereby by inserting this into the same lock they may open the
cabin door, but cannot re-lock the door or withdraw their key again until released
by the inserting of the separate key of a constable in the inside or opposite key-
hole of the lock. The opening of the cabin door by the citizen's key will also by a
mechanical connection from the lock automatically raise the signal shade or light
to attract the attention of a district constable to the cabin, and the citizen after
having opened the door can communicate by the telephonic instruments and
electrical connections inside, with the central station to request police assistance,
call up fire brigade, or give or receive other instructions.
And in order that my said invention and the manner of performing or carrying
the same into, effect or practice may be properly understood, I have hereunto
appended two explanatory sheets of drawings, in which the same reference letters
are used to indicate corresponding parts in all the figures where shown.
Figure 1 on Sheet 1 is a sectional elevation showing the interior of a police
signal box or cabin with part of the electrical, telephonic, and gas connections and
fittings as arranged in accordance with my improvements.
Figures 2 and 3 are detached elevations, to an enlarged scale, broken away and
at right angles to each other of the gas supply and controlling mechanism, the
shade or signal globe being shown in Figure 2 in its lowest fixed position with only
the gas pilot light burning as in Figure 1 while in Figure 3 the shade is shown
in its highest signalling position with the main gas light burning, the pilot light
being in this figure shown in front of the gas pipe to distinguish same more
clearly.
Figure 4 on Sheet 2 is a sectional elevation of the police signal box shown in
Figure 1, showing the door and some of the electrical and operating connecting
fittings more clearly.
Figures 5 and 6 are detached sectional elevations broken away, at right angles
to each other, showing the electrical connections at the operating contact bolt of
the lock, and the mechanical connections through which the signal shade is actuated
by the citizen's key..
Figure 7 is a detached sectional elevation of the lock in the reverse position
to that shown in Figure 5, and showing the citizen's key as having operated
same.
and
Figure 8 shows side and end views of the inner tumbler lever of the lock, and
Figure 9 corresponding views of the front or outer tumbler lever; while
Figure 10 shows similar views of the locking or operating bolt and switch plates,
Figures 11 and 12 show views of the constable's or policeman's and citizen's keys
respectively.
Referring to these drawings:-The improvements would be carried into practice
under, this arrangement all as follows:-The signal cabins would consist of

page_text: hexagonal, or other shaped boxes or buildings A, preferably built of metal plates,
with overlapping layers of glass A' above, and with a gas lamp A' overhead outside
supported on brackets A", from the cabin, or it might be on a post or standard,
while an opening and closing door A³ for entrance to the cabin A would be fitted
at one side, as shown in Figure 4. The gas would be supplied from the ordinary
street gas main pipes to duplex vertical pipes B, B, and from these to a transverse
horizontal connecting pipe B', and a pipe 132, leading from it to the lamp burner B³
and having a tap B on one gas pipe B for being raised or lowered in pressure or
light by the police or ordinary street lamp attendants, and having a byepass
valve to be automatically operated by the raising of the shade signal C, as
hereinafter described. While à branch connection B, would be taken from the
tap B of the gas pipe B to supply with gas a burner B³, to always keep
burning and act as a small pilot light for igniting the gas issuing from the
burner B when its supply valve ↳ is open. An ordinary bracket gas pipe B
with burner and tap would preferably be fitted to one of the pipes B, for lighting
the interior of the cabin A. Electric line wires would be carried from the central
station, either on poles and insulated supports overhead or in channels underground
much in the usual manner in which telephone wires are carried, and electrical
circuit connection made with each cabin A. A main line wire D would be .con-
nected to a terminal D', on a plate at one side of the door, and a connection made
from this through a flexible cord D₁ to a terminal d on a plate at the top of the
door A of cach cabin A, where other two terminals d², d³, would also be placed,
one on each side, as shown in Figure 4 with wire connections through the cord D+,
from the terminals D², D, and parallel insulated wires d', d, would be led
from each of these terminals d, d², d³, round channels or spaces formed on the inside
surface of the cabin door A³, and each connected to separate switches, preferably
spring blades or plates e, ell, el, near the door lock F, as shown in Figure 5.
Two contact plates e, e², would be fitted on the inner end of the sliding bolt j, of
the lock I, preferably of an shape, and one of the side spring switches e", or e
would be in contact with each plate el or e² respectively while the centre or current
line spring switch e can be placed in electric contact with either plate e or e",
according as the bolt, is locked or unlocked. The two side wires d,, leading
from the spring switches e", e, to the terminals,, at the top of door A³, and
from these to the terminals D², D, would further lead from these latter
terminals D2, D", respectively by the wires D³, D, the one D³, to supply electric
current to operate an electro-magnet E, actuating the lamp shade lever from
whence it passes by a wire D4 to the switch plate C8, and by a connection D' to the
gas pipe B2 leading to earth, and the other wire D₁ supplies current to establish
electric connection with the telephonic instruments T, placed within the cabin A,
the circuit being made to earth through the wire D, and gas pipe B. The red
coloured glass shade C, which is preferably of an annular shape to surround the
light is held in a lower basement frame C, by vertical guide bars C and adjust-
able screws at top, and is attached to vertical guide rods C, C, and automatically
pulled up into and held in the raised exposed position by weights W, attached to
cords or chains W₁, passing round guide pulleys W³, secured by a transverse
bracket to the fixed gas pipe B2, as soon as released from the catch c¹ on the short
vertical arm of a bellcrank lever c, c', preferably fulcrumed at on the traus-
verse gas pipe B'. The longer horizontal arm c¹ of this lever c, c', has a spring
catch armature lever fulcrumed at c³, connected with it by a spring catch at
and which is disengaged by the electro-maguet E when a current is sent through it
to release a catch arm from the lever, and which action disengages the catch *,
and the arm c, will then spring up by the action of its weighted end e* to free the
catch on the arm c, and permit signal shade C to be raised by the weights W,
and the end of this lever c' is guided in a longitudinal slot in the frame E of the
electro-magnet. When the signal shade C is elevated the pins at C, on the guide
rods C, automatically raise the spring switch C³, to break the clectrical connection
with the electro-magnet E, while the shade is up, but when the shade C, is pulled

page_text: down by hand through the chain 6111 and connecting rod, the upper set of
pins C, on the rods C, pulls down the sleeve C, and springs C5, and re-establishes
through the switch plate Cs, electrical connection with the electro-magnet E, the
plate C, being secured to an insulated ring fixed on the gas pipe B, which leads
to earth.
The
The mode of operation is as follows:- When communication is desired to be
established between the officers at the central station and one of the signal
cabins A. they turn in the ordinary manner the telephone crank handle in con-
nection with that cabin, and by so doing send a current through the main line
wire D, and its spring switch on cabin door A³, on to terminal contact plate
of signal wire switch e", (with which when the cabin door is locked it is always
in contact) and the current is thus sent through the signal wire d to the coils
of the electro-magnet E, which attracts the armature and frees the catch e,
from the lever c, and this releases the horizontal arm of bellerank lever from
the spring catch e, and which action releases the catch e, on the vertical arm c
of this lever, c', from catch c¹, on the sliding sleeve W to free the contact
with signal globe shade C, so that the weights W, will raise it to surround the
light. The raising of the shade signal C, carries with it the guide rods C', and
sliding sleeve W, attached to same on which the catch is fitted.
pins C on the rod Craise the sleeve C, and springs C to break the electrical
connection with the earth switch C, and so break the circuit, and the ringing
of the call signal alarm bell in the central station will then cease and the
operator will know that the shade signal C has been raised. A stud or pro-
jection w, is formed on the sleeve W, and has connected to it the end of the
rod, and the operating lever of the byepass valve h, is connected at 1, to
this rod so that when the signal C is raised, as shown in Figure 3 the
byepass valve is opened to admit full pressure of gas in lamp, and thus signal
to the nearest constable that his services are required in the cabin A. When
the constable opens the cabin door A³, as shown in Figure 5, by inserting and
turning his key, shown in Figure 11, in the lock F, this action slides the
locking bolt along and shifts the line wire switch e, from the electric contact
plate e, of signal wire to the corresponding plate e of telephone wire D
which enables telephonic communication to be established between this cabin A,
and the central station. The constable first however after entering the cabin A
would draw down the hand cord or chain attached to lamp shade C, to bring
down the latter to its lowest position, where it would be automatically held by
the catch connection c¹¹ on the bellcrank lever c, c', as shown in Figure 2, and
by this means avoid another constable in the district being taken off his duty
to attend to the signal. The pulling down of the shade C, brings down the
lever of the byepass valve b and shuts off the gas supply from the main
burner 13, and the strain of the pulling down action is relieved from the valve
and valve lever b,, by the spring and slot *. The constable can How
receive instructions from the central station by the receiving and transmitting
telephonic instruments T', T', in the ordinary manner. Or if he entered the
cabin A without receiving a signal he can transmit requests or instructions to
the central station in this manner, without showing the shade or visible signal C.
When the constable is finished and leaves the cabin A, the movement of the
sliding bolt in locking the door A³, will automatically shift the switch e of
main line wire from the telephonic line contact switch plate e² on to the signal
line switch plate e, ready to receive the next signal.
When a party possessed of a citizen's key, shown in Figure 12, desires to
enter signal cabin A, the action of inserting and turning this key in the lock F,
shifts the line wire switch e, on to contact plate e, of telephone wire which
enables the citizen or person to communicate by telephone T inside cabin with
central station. The same action of turning citizen's key in lock Fraises a
vertical rod sliding in guides y" on the inside surface of the door A³, and this
action raises a sliding bolt g!, passing through the top guide g, so. that when

page_text: the door is opened this bolt g', engages with a spring catch g, which pulls the
lever fulcrumed at g to depress the spring piston G working within an air
cylinder G. A tube connection G, is made from this cylinder G', to a corre-
sponding small sized cylinder G with piston G³, mounted on the stand E", of
the electro-magnet E, so that when citizen opens the door and the piston is
depressed the air pressure passes through the tube G, and acts on the piston (³,
in the cylinder G, to raise this piston to act on the catch and release the
lever which in turn releases the lever c', through the spring catch c, to
disengage the catch and permit the shade C to automatically ascend to its
raised position to communicate to the nearest constable that his presence is also
required at signal cabin A, to take instructions. And the same action of turning
the citizen's key to shoot or slide the locking bolt in opening, cabin door A³
further locks said key within the lock, as shown in Figure 7, and prevents the
door being re-locked or the key being withdrawn until it is released by a
constable's key being inserted in a special keyhole of lock inside door, to
allow citizen's key to shift or adjust the sliding bolt. If the constable should
desire to signal for an additional constable in the district while he is speaking
at telephone T, he can raise the lamp shade C, to do so, by pressing the lever g³,
by hand to operate the pneumatic arrangement as before described.
at
The improvements in the lock to enable the two keys to actuate it as described,
consist, as shown in Figures 5 to 12, in having two tumbler levers F, F,
Figures 8 and 9 respectively, fulcrummed on a pin F, and taking on to one
lateral catch on the bolt to fix the bolt in its outward locked position by
the notch F, in the tumbler lever F, or its inward. unlocked position, as shown
in Figure 5, when the constable has opened the door by the notches on the
lever F, and F, on the lever F¹. The constable's key, Figure 11, is made
to lift both tumbler locking levers F¹, F, and unlock or lock the bolt f
substantially in an ordinary manner; but the V part 2 of the bolt is formed
with a projection f³ on its inner side half the depth or thickness of bolt, which
the constable's key passes and throws the bolt fully open so as to pass and be
removable. But the citizen's key, Figure 12 is made with a projection
this projecting part of the bolt so as to throw and unlock the bolt after
raising the locking or tumbler lever F, and be itself locked in the inner position
of the bolt, by the other tumbler lever F, which it allows to drop by one of
its notches F, while holding up by the projection h¹, on the key the other
tumbler lever F, which raises and keeps up the vertical operating rod g. The
key will remain in this locked position until released by a constable's key
inserted in the keyhole ", on the inside of the lock fitted with a special ward
plate exactly fitting the constable's key, which by a special projection F³ on
the said locking tumbler 2 raises it, and so allows the citizen's key to shoot
the bolt and be turned and withdrawn, at the same time lowering the vertical
rod Y: while a citizen's key cannot pass the ward plate on the inside of
door lock F.
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 :-
First. The system of, and arrangement and combination of mechanism and
appliances for, communicating visible signals, and establishing electrical and
telephonic connection between central town and district signalling stations, and in
which means are provided for the doors of the district cabins being opened by
constable's and citizen's keys, substantially as herein described in reference to
and shown in the accompanying drawings.
Second. In a system of communicating visible signals and establishing electrical
and telephonic connection between central town and district signalling stations,
the arrangement and use of lever mechanism for holding the signal shade down
in its lowered position, combined with the electrical connections and mechanical

page_text: appliances for releasing the shade and automatically bringing it to its raised
signalling position, and controlling the gas or light supply, substantially as herein
described in reference to and shown in the accompanying drawings.
Third. In a system of communicating visible signals and establishing electrical
and telephonic connection between central town and district. signalling stations,
the arrangement and use within the district cabins of switch plates on the sliding
bolt of the door lock, with connections. and fittings for electrically actuating the
shade signal, and establishing telephonic communication, substantially as herein
described in reference to and shown in the accompanying drawings.
Fourth. In a system of communicating visible signals and establishing electrical
and telephonic connection between central town and district signalling stations,
the method of operating the lock on the district cabin doors by constable's and
citizen's keys, and establishing communication thereby, substantially as herein
described in reference to and shown in the accompanying drawings.
Fifth. In a system as described in Claim 4, the fitting and use in the district
cabin doors of locks in which the sliding bolt is controlled by two tumbler levers
and operated by two sets of differently formed keys, substantially as and for the
purposes herein described in reference to and shown in the accompanying drawings.
Dated the 18th August 1892.
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents."