US915075A

US915075A - Signaling system.

Info

Publication number: US915075A
Application number: US19869504A
Authority: US
Inventors: Nathaniel Banks Cregier
Original assignee: Individual
Current assignee: Individual
Priority date: 1904-03-16
Filing date: 1904-03-16
Publication date: 1909-03-16
Anticipated expiration: 1926-03-16

Description

11,13. GREGIBR. SIGNALING SYSTEM. APPLICATION FILED EAR. 16, 1904.

Patented Mar. 16, 1909;

k 2 SHEBTSSHEET 1.

- N. B. GRBGIER.

' SIGNALING SYSTEM. APPLIOATION FILED MAR.16, 1904.

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Z'e'izzewea;

UNITED STATES PATENT OFFICE.

NATHANIEL BANKS CREGIER, OF CHICAGO, ILLINOIS.

' SIGNALING sxs'rnm.

Specification of Letters Patent.

PatentedMarch 16, 1909.

Application med March 16, 1904. Serial No. 198,695.

To all whom it may concern:

Be it known that I, NATHANIEL BANKS Cnncrnma citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Signaling Systems, of which the following is a specifics:-

tion.

This invention relates to an electrical signaling system and particularly to a police signal system used for transmitting signals between police patrolboxes and headquarters or acentr station; and it has for its object, generally, to provide a central energy police telep one signal system designed to render the operation of signaling more speedy and perfect of control and to avoid certain objections and disadvantages in the systems heretofore employed.

I'Vith' the systems generally employed, it is in such systems are in series with each other,

and that no adequate means have been pro.- vided' for detecting errorsin false reporting to which such systems are open. -To avoid this false reporting and compel every patrolman to re ort only from the box in his ownv place the signalingapparatus ofterritory, each patrol ox in an individual circuit, and in such circuit at the central station I rovide a signaling device of a suitable c aracter which will indicate to the operator, either by reference to the number of the box or other means, the location of such box.

The 0 erator having been given the name of" the o 1081' reporting, is thereby enabled to determine immediately, of the trolled proper territory. y 7

A further and important object of'the invention is toprovide means independent of I from his knowledge patrolmans name and the beat a the talking apparatus and over the same line for indicating to the operator at the central station that the fatrol-wagon is desired, and the exact 1008171011 of the box to which the patrol to be sent. Broadly,

such means may comprise suitable signaling him, whether he is on duty in is devices located at the central station and capable of being actuated only from the patrol box on the same circuit, and having:

associated therewith indicia for informing the operator of the-location of the box sending in the call and to which the patrol wagon is to be directed.

Another object of the invention is to provide a novel circuit arrangement particularly adapted to pohce telephone slgnal- .mg-systems and capable of accomplishing certain new results in the transmission'of signals between the patrol box substation included in such circuit and the central station.

' Another object of the invention is to dispense with the usual drops and plugs and manually operated switches ordinarily employed with police telephone signaling sys-' tems and to render the action of t devices at the central station automatic in all particulars.

Other features of the invention and further objects and advantages thereof, other than those already mentioned, will be hereinafter pointed; out in the accomie signaling practically panymg' description. The invention consists of the combination of parts and circuit arrangement now to be described, particularly designated in the e'lalms and-illustrated in the accompanying drawings, in which.

Figure '1 is a diagrammatic view of the circuit, illustrating the apparatus at the central station and a patrol box and the connections therefor; Fig. 2 is a front elevation ofa central station switchboard fitted up with the signahappar'atus and details employed with my invention, and showing.

m connection therewith twopatrol box substations, one. of which has the outer door open to disclose the arrangement of the telephone outfit, while the other box is shown with the outer door closed; and

Fig. 3 is ,a detail of the switch at the patrol box and which is desi ned to be controlled by the outer door of the box to alternately I connect and disconnect the call bell and answer back signal to and from the line.

The central station is provided with an operators telephone set T, ringing generator N, pilot light m alarm F, and battery 3 which: are common to all-the circuits, the

pilot light and alarm being actuated when ever a signal is sent in from any patrol box of 119 the system,and-while in Fig.1, in order to conduce to cle'arness, I have shown the system with-circuits and connections complate for only one patrol-box station, it is to e understood that the number may be increased indefinitely and that the- Wiring and connections of all circuits are the same. Each patrol box P is provided with a telephone set, which may be of the usual or any suitable character, but which. preferably comprises the apparatus and circuit arrangement shown in Fig. 1. The line B leading from the central station terminates at a binding post 1, from which leads a wire 3 connecting with line 14 leading to transmitter 16, and from the latter a connection .17 leads to the primary winding .of the induction coil 15. From the latter a con- .-nection 18 passes to the contact 13 of the with or disconnect them from the line,

' leads a wire 1') 0'0 which means may consist of the usual ringing and listening keys. Such keys, designated k, are mounted on the table or ledge of the switchboard B in the usual manner, as

.shown in Fig. 2, and which, as they are of ordinary character, it has not been deemed necessary to show in Fig. 1. The lines A and B are normally in'circuit with a relay designed, when energized, to close a local circuit to actuate a signal to notify the operator of the location. of the box from which the signal emanates. In making connections from the substation to the central station the line A is connected to the spring a of the ringing and listening key associated with the circuit and from the spring a a connection 0 leads from a 0011-. tact a." with which the'spring a is normally,

in engagement. From a wires at and a lead to relay D. From the winding of this relay a line (1 connects with one side ofthe battery Y. The line B is in electrical'connection. with the other spring I) of the ringing side of the listening key which is normally in engagement with a contact If, from which. ected to wire I) leading to the otherside of the battery.

The operator's telephone set T which is j common to all of the circuits in the system,

comprises the usual receiver t, transmitter t", connected by wires t t,,with the batte Y, and connections i ft, provided wit contact points t with which the s rings i t, at the listening side of the key li engage when'the o erators key is thrown to the position to ridge in his telephone set with the line.

The circuit being normally open at the substation, when the receiver 11 is removed from the hook the hook-switch 12 moves against the contact 13 thereby closing thecircuit. This allows current from the bat tery Y for talking b wire 5 contact wire 18, contact 13, wire 19, to terminal 2,

urposes to flow over lineline B, terminal 1, wire 3, Wire 14, through the transmitter 16, wire: 17, primary windlng of the induction coil 15,

and by line A ,to contact a ,"wires a a;*, a g and through relay D to line (1, thence to the opposite s1de of the battery Y. 'The closing a visual signal so located and arrange asto indicate to the operator at a glance the location of the box from which the receiver is removed from the hook 'In carrying out this feature of my invention provide at some convenient position, as at S, on the front face of the receiving board so as to be readily seen by the operator adiagram, plat or other suitable medium whereby or map the operator may be informed when the receiver of any its hook, of t e exact location of such box and know when he learns the name of the officer reporting whether or not such oflicer is reportin from the proper box. S ecifically of the circuit energizes relay D which closes a' local circuit at the central station to o crate. p

patrol box set is removed from such me ium comprises a map or p an of the locality served by the system, andsuch map, which is arranged in the order ofthe streets of the territory covered thereby, may be provided with the names of the streets, and'at each point corresponding with the location'of.

a patrol box is placed a signaling device which when actuated will indicate to the o erator at a glance the location of the box associated therewith. Such signal in the pres.- ent instance takes the form of an incandescent lamp m, the front of the-board being:

provided with anopening to show the illumination of the lamp. When now the relay'D is energized by closing the circuit at the patrol box, the armature d of the relay D is attracted, closing the local circuit in whichthe lamp m is included and the current from one side of the battery passes through theline 11,

line (i tapped from the line 11, armature-d? which is moved against the anvil d. of'line (1 line d connected to .the armature (1 to the lamp m,'then by wire (1? to-thefother side of the battery, thereby illuminating the 'lamp m. When the patrolmans receiver is hung up the relay D isof course deener ize'd and the local circuit being opened the ampm is extinguished.

In order to indicate to the operator at a glance the particular ringing and listening kely associated with. any circuit avisual or ot e r suitable signaling device is" provided and located in such position as to. denote the ringing and listening key to be mani ula'ted to throw the .operators set. on to t e line when a patrolman calls u To this end each ringing and listening ey, as shown in Fig. 2, has associated therewith a lamp m which isso positioned as to show by its illumination the he of the circuit controlling the lamp. This lamp 111 may be arranged in multiple with the lamp m and also cont-rolled by the energization of the relay D to illuminate the said lamp m For this urpose connection is made by a wire (1 in e ectrical extension of the armature d and including the lamp m such wire connecting at its other end with the wire (1 It will be understOodirom this that when the relay is energized'in the manner heretofore described, current is thrown through both the lamp mand the lamp m ofthat particular circuit, the former lam indicating from its location on the map the ocation of the box calling up the operator, and the latter the articular listening key associated with su'c 1' line. I may also provide an audible alarm to attract the attention of the-operator, and this alarm, which may consist of the bell F, is loeated at some convenient position on the receiving board, as shown in Fig. 2, and'is actuated by an electromagnet fin aloeal circuit controlled by a relay R common to all the circuits of the system. This relay R is in series with the lamps m, connection in the present instance being made in the line d eading from the said lamps to the battery. When the relay R is energized the armature thereof is attracted against the contact 7, and current then flows by wire 7 connected to the wire d, from one side of the battery through armature r, wire j, through the electromagnetf", and by wire f to the other side of the battery. This energizes the magnet f and attracting its armature j, which 18 provided with a cla per fl, gives the bell F a single tap. The iot lamp m maybe included in the l-inej in series with the electromagnet f, and provides a visual signal, and 45 this pilot light 13 preferably located on the receiving-board in such position as to be under the eyes of the operator and serves to attract his attention to the map lam s m, for this pilot light being. common to al the cir- 50 cuits it remains lighted so long as any of the map lamps m continue to burn. This prevents the operator from overlooking any call from a patrol box.

The lamp m indicates to the operator the key to bemanipulated to cutin his telephone set in order to communicate with the officer calling up, and he then throws his key to talking positionbr so as to move the springs t and-fagainst the anvils t This operation does not affect the line to the lamps owing to the permanent connections of the wires (1 b past the sprin s z ,t", and'such lamps con tiuue to burn. he operator is of course assumed to know the names of the patrolmen and the territory patrolled by them, and as soon as he receives the name of the oificer reporting he has only to referv to the lamp m corresponding with the box from which the report is received to inform himself whether or not the patrolman is at his proper station.

By means of the intercommunicating telephone sets the operator and patrolman are enabled to report or send necessary instruc-' tions to and from headquarters. When the patrolman hangs up his receiver on its hook the relay D is denergized, its armature dro ping back and thereby opening the local circuit and extinguishing the lamps m, m Relay R is also denergized to open the local circuits controlled thereby an thus decriergizes the magnet f so that it releases its armature to reset the bell mechanisms and also extinguishe's the pilot lamp m T he patrol substation'boxes may be of any suitable character or construction, but they preferably comprise a rectangular box 25 provided with two doors hinged at opposite sides of the box so as to open in opposite directions. T he chamber closed by the inner door 26 is designed to contain most of the apparatus located at the substation, only such parts as are necessary in the ordinary use of the system being placed in front of the door 26, such for instance as the receiver 11, which is supported by the book 12 and is located in a recess or depression 27 on the front of the door '26, the mouth piece of the transmitter 16, and certain other parts to be hereinafter mentioned.

Located at each patrol box is a generator 20, the handle 28 for operating which extends in front of the door 26, so as to be inanipulated when the outer door 29 is open. This generator 20 may be of the alternating type, and is designed to be cut into and out of the main line of the circuit by means of a switch mounted on the box and operated by the outer door 29. This switch comprises a pair of contacts C, C, tied together and connected by a wire 22 with one side of the generator 20, and with which a air of switch springs G, C, are designed to e moved into engagement when theouter door 29 of the box is open. The springs C, C, are also tied together and a wire 4 leads from-them to the main circuit, being shown connected to the wire 3. From the opposite side of the generator 20 a wire 21 leads through a ringer 23, and a line 24 extends from the latter to a condenser 8 which is connected by wire 9 to the wire 19 terminating at the terminal 2. The switehoperated by the door of the box is also provided with a pair of contacts C C, also connected together and from the same a wire 5 leads to a-reeall bell 6, a connection 7 from the latter leading to line 24 connected, to the condenser. T he hell 6 is designed to i be mounted inan exposed position, and preferably upon the top of the patrol box, a ood 30 being provided to protect the same.

The switch at the patrol box, shown on a larger scale in Fig. 3, comprises a bracket h fixed to-the inner side of the door 26 by a nut 72. threaded upon an apertured lug gojecting from'the bracket and extending t ough an opening in the door 26. Passingthrough an 9 aperture in the lug is a plunger 72. having a the generator 20 an actuate-d when the generator is manipulated. Located at convenient positions on the board beveled portion k which is adapted to engage the ends of the switch springs C, C, and move them out of contact with the contacts C, C, and into contact with the contacts C C The contacts and switch springs are mountedon an'insulating block 72.", secured on the bracket 71., and reacting between the block and shoulder k on the plunger is a coiled sprin it". When the door is opened the lunger 1s thrust outwardly by the s ring it re easing the switch sprin s C, C, an per= mitting them by their own elasticity to move against the contacts C, C, thereby disconnecting the branch circuit including the recall bell 6 from the line and connecting the branch circuit containing the generator-20 and the ringer 23 with the main circuit. When the door 29 is closed the plunger 71. is forced inwardly separating the switch springs C, C, and moving them a ainst the contacts C, 0 thereby opening t e circuit through closing the circuit through the ringer 6. This is the normal condition of the circuit.

The generator 20, located in each box 25,

: attention to communicating his wants to the central oflice while he is able to operate the magneto without trouble. A special signal is provided at the central oflice which is are ringers G, one being associated with each patrol box circuit, and. such ringer is designed to' control means for actuating a visual signal to notify theo erator that'the atrol we on is .desired at t e point to 'whic it is to e sent. This ringer may be 'of any character capable of actuation upon the manipulation o the generator 20, ut is prefera ly of the polarized type, and in the present embodiment of the invention is inserted in the wire I)". The ringer G controls a local circuit in which is included a lam g before which is placed a transparency g earing any suitable matter indicating the location of'the is included I rovide a pivoted finger g which is norma y supported in inoperative osition-by the tapper g of the ringer or a or projecting t erefrom. When the patrolman operates his generator current passes over line21, through the bell 23, wire 24, to one side of the condenser 8, over wire 9, wire 19, line A, connection a, line a, line a relay D,

line (1, battery Y, line b through the polarized ringer G, connection 12 line B, line 3, line.

4, contacts 0 C, and C, 0, wire 22 to the return side of the generator, thereby actuatingthe ringer G.- \Vith the firstmovement of the tapper g the finger g is kicked off and, through the medium of ajcontact g closes the circuit throughan anvil g; Thecurrent from one side 'of the batterythen flows throughline g, contact g ,'line g lam 9,

line g, thence to the other side'of the attery, as by a connection with the line d. This action-lights the lamp 9 and displays the transparency of the particular circuit operated to inform the operator to what box nicates with the ofiicer by connecting in with the line his generator N to ring the bell 23 to notify the otficer that the wagon will be sent or that it is not in. It will be understood 7 that at this time the outer door 29 is open and that therefore the ringer 23 is connected to the main line. The lamp 9 remains lighted until the operator, after the bell G has ceased ringing, moves the fingerg back against the clapper 9 this action breaking the contact at g and extinguishing the lamp. The finger 9 may "have a lug 9 to enable the op erator to readily restore the finger and a stop g is preferably providedfor limiting the movement of the finger when thrown off by the tapper g.

The polarity of the ringers G issuch that 1 by the current generated by the generator 20- in the patrol box.

' The recall bell'6 located in each box is designed to attract the attention of the patrolman in'the territory in which the box is located, should it be necessary to communicate with him for anypurpose between the. hours of reporting,for example, to instruct him to report at aparticular place, as in case of a riot or confiagration or for other reason. This bell is operated .by the ge erator N, having the usual ringing indicato n,-in the same manner as. in operating the' ringer 23. When the operator desires to actuate this bell to attract the attention of an oflicer within audible distance of the box, aringing current is thrown on the line by the operator at central, this ringing current coming over line B, line 3, line 4, switch springs O, C,

contacts 0, C, which are closed when the provided with bells of such size as to be readily audible for a considerable distance.

' When an officer responds to such call he pens the outer door of the box, which allows p unger h to be forced outwardly, permitting the switch s rings C, C, to close against contacts'C, and when the receiver is removed fromthe switch hook 12 he is enabled to talk with central over the circuit heretofore described. l v

' A jack 9' may be inserted in each circuit at the central station so that by the use of theusual cord circuits and plugs a patrolman ma any of'his superior oflicers or with the public system terminating atjacks on the board; Such jack 7' may be of any suitable character and is looped in series with the lines a, a, as shown in Fig. 1. v

While I have described with particularit the connections and wiring of the system wish'it understood that the details in this respect are not essential and that various modifications may be made'without departing from the spirit of my invention; The

switch controlled by the door at the substation is shown and described with a pair each of the contacts'and springs, each pair being tied together. This arrangement provides a stronger and more reliable construction, but it will be understood that instead of a' pair only one of each of the contacts and springs is .essential and that with this change the operations and results would be just the same. i, s

Having described my invention, what I clairnas new and desireto secure by Letters Patent is I l 1. In combination, a telephone system including a central station and a pluralityof.

substations with individual circuit connect1ons,.'a diagram at the central station of the territory in which the substations are located, and a visual signal for each substation on the diagram in the corresponding location of-each substation, and means at each substation to actuate such si nal,

In a signa ing system, a central station and a plurality of substations, a diagram at the central station of the territory surrounding the substations, visual signals at the central station for each substation, one of said signals being associated on the diagram with the location of the respective substation for indicating on the diagram theexact location from which a signal is sent, and meansat each substation to actuate its associated sig nals at the central station.

,3. In a signaling system, a central station be put in direct communication with.

switch-board, a

switch-board, a.plu'rality of telephonesubstations, a map on the switch-board of the territory surrounding the. substations, a

visual signal on the map at a point correspending with the location of each substation, a second signal at the central station associated with each substation, a normally open circuit between each substation and its asso ciated signals, said signals" being automatically actuated when calls are made atthe substation. V 4. Ina signalin system,.a.central station switch-board, a Iurality of patrol substa-'.

tions, a map on the switchboard of the terri+ tory surrounding the substations, individual telephonic circuits between the substations andthe central station, a lamp on the map at ply current to said lamps upon the removal of the telephone receiver at the ass oclated substation, and an operators key-indicatin signal on the switchboard for each lamp an actuated simultaneously with the latter.

5. In a signalin system, a central station Iuralit of' patrol substations, an indivi ual te ephone circuit between the central office and each substation and normally openat the latter, .a rela in each circuit, a ma on the switchboard o the territory surroun ing the substations, lam s on the map at points corresponding with t e locations of the substations, a normally open local circuit in which each lamp is included and which is closed by the relay when the telephone receiver at an. substation is removed from its hook, an a second normally open local circuit at the switchboard containing 6. In a signalin system, a central station switch-boar a p urality of telephone substations on individual circuits, a relay in each circuit, a substation indicating signal, a series of operators keys associated with the circuits, an indicating signal for each key controlled by the relay of its associated circuit, a relay common to all the circuits, and a signal controlled by the latter relay. 7. In a signaling system, a plurality of telephonic lines extending from substations to a central'switchboard, signals at the switchboard associated with the lines, a series of ringing and listening keys on the switchs board, each key being in an associated line, a signal at each key, and connections to operate a key-signal when its line transmits a call-signal.

tery common to a the circuit connections,

a bell and adapted to be closed by the closing of the line circuits.

a point corresponding with the location of a relay in each circuit which is actuated by the closing of the circuit at the substation, a diagram at the central station of the territory surrounding the substations, signal devices on the diagram'at points corresponding with the locations of the substations, a local circuit connected with the .battery in which each signal device is included and which is closed upon the energization of the relay, an operators connecting apparatus at the central station associated with each circuit, and a lamp indicating the location of such apparatus and which .is illuminated upon the actuation of the relay.

9. In a signaling system, the combination with a central station and a plurality of patrol substations, of individual metallic circuit connections between the central ofiice and each substation and normally open at the latter, a battery common to all the cir; cuit connections, a relay in each circuit and which is actuated when such circuit is closed at the substation, a map at the central station of the territory surrounding the substations, incandescent lamps on the ma at the points corresponding with the locations of the substations, a local circuit connected with the battery and in which each lamp is included and which is closed upon the energization of the relay, an operators ringing and listenin key associated with each circuit, and a amp indicating the location of such key, such amp deriving current from the common battery and being illuminated upon the actuation of the relay.

10. In a signaling system, the combination with a central stationand a plurality of patrol substations, of ,individual metallic -circuit connections between the central ofiice and the substations and normally open at the latter, a source of current common to all the circuit connections, a relay in each circuit and which is actuated when such circuit is closed at the substation, amap at the central station of the territo surrounding the substations, incandescent amps on the map at the points corresponding with the loca tion of the substations, a local circuit connated upon the actuation of the relay, a sec- 0nd relay controlled by the first relay, and a norm'allyopen local circuit including an alarm and a pilot light closed upon the actuation of the second relay.

11. In a signaling system, the combination with a central station and a plurality of patrol boxes provided with telephone sets, ofnietallic circuits connecting the telephone sets'with the central station, a source of energy common to all the circuits, a door to each box, a call bell normally connected with the circuit, a ringer normally disconnected from the circuit, a contact in the line of the call bell circuit, a contact in the cir-, cuitof the ringer, a switch spring, a lunger pressing the switch s ring against t e con-v tact in the call bell ne when the door is closed, and a spring for withdrawing theplunger to'permit the switch spring to en-' gage the contact of the ringer circuit when the door is opened, and means at the central I station for actuating the ringer and bell.

12. In a signaling system,the 'conibination with a central station and a plurality of patrol boxsubst ations, of metallic circuits connecting the central station and the substations and provided -ith telephone sets at the substations and normally open at the snitch-hook, a source of energy common to all the circuits, a normally closed branch circuit at each substation, a bell in such circuit, a second branch circuit provided with a ringer, a switch spring for opening andcloslng the branch circuits 1n alternation, a

plunger mounted on the box and engaged bv the ,door when closed to close the call bell branchcircuit, and a spring for thrusting the plunger outwardly to break the call bell branch circuit and close the ringer branch circuitr. hen the door is opened.

13. In combination a ith a central energy telephone system comprising a central station and a plurality of substations v. ith in-' dividual circuit connections, a current gen-- erator at each substation, a signal at'central for each line and operated by the removal of the associated receiver, and a signal at central in a 'normallyopen local c1rcu1t deriving current from the central source of energy "and closed upon the actuation of ,the associated substation generator.

14. In a telephone signaling system, the

signal is included and deriving current from,

the said common source, and means at the central station actuated hen a substation alternatin current generator is operated to close the local circuit to operate the visual signal of such substation.

15. In a signalin system, in combination, a central energy tdlephone system comprismg a central statlon and a plurality of substations with individual circuit connections and a current generator common to all the circuits, a polarized ringer in each circuit closer actuated by the polarized ringer for closing the local circuit.

16. In a signaling system, in combination, a central station and a plurality of substations, circuits connecting the central station and the substations and provided with alternating current generators at the latter, a source of current common to all the circuits, a visual signal associated with each circuit and included ina local circuit at the central station connected with the common sourceof current, an audible signal in the main circuit and u hich is operated by the alternatin current generator at the substation, and means controlled by the audible signal for closing the local circuit.

17. In a signaling system, in combination, a central station and a plurality of substations, circuits connecting the central station and the substations and each of which is provided with an alternating current generator, a source of current common to all the circuits, a lamp at the central station associated with each circuit and provided with a.

transparency indicating the location of the substation, a local circuit in which such lamp is included, a ringer in the main circuit and responding only upon the actuation of the alternating current generat or at the substation, and a pivoted contact normally supported by the tapper of the ringer and which upon the actuation of the ringer is moved to close the local circuit.

18. In a police telephone signaling system, in combination, a central station and a plu rality of substations, circuits connecting the central station and the substations and normally open at the substations, telephone sets in the circuits at the substations, a normally closed branch circuit at the substation provided with a call bell, a second normally open branch circuit at the substation prov ded with a ringer, means for connecting and disconnecting the branch circuits to and from the main circuit in alternation, a rela in the circuit at the central station and whic is actuated upon the closin of the circuit at the substation, a signal at the central station indicating the location of the substation and included in a normally open local circuit, an

'operators telephone set at the. centralrstation, keys for connecting the telephone set with the circuit, a lamp associated with each key and included in a local circuit which is closed upon the energization of the relay, and a battery common to all the main and local circuits.

19. In a police telephone signaling system, combination, a central station and a plurality of substations, circuits connecting the central station and the substations and normally open at the latter, telephone sets in the circuits at the substations, a branch circuit at each substation, a call bell in such branch 7 circuit, a second branch circuit at each substation, an alternating current generatorv and a ringer in the second branch circuit, a switch at each substation for connecting and disconnecting the branch circuits to and vfrom the main circuit in alternation, a battery at the central station common to all the circuits, amap at the central station of the territory in which the substations are located, a lamp on the map at a point corresponding to the location of each substation, a local circuit in which such lamp is included, a relay in the main circuit for opening and closing the local circuit, an operators tele phone set at the central station, keys for connecting and disconnecting the operator's telephone set with the line circuits, a lamp associated with each line circuit and indicating the key associated with such circuit, a local circuit including an alarm and a pilot light, a second relay controlled by the first relay'for closing the alarm circuit, and'a current generator at the central station for actuating the bell and ringer at the substations.

20.- In a police telephone signaling system, in combination, a central station and a plurality of substations, circuits connecting the central station and the substations and normally open at the latter, telephone sets in the circuits at the substations, a branch circuit at each substation, a call bell in such branch circuit, a second branch circuit at each substation, an alternating current generator and a ringer in the second branch circuit, a switch at each substation-for connecting and disconnecting the branch circuits to and from the main circuit in alternation, a battery at the central station common to all the circuits, a map at the central station of the territory in which the substations are located, a lamp on the map at a point correspondingto the location of each substation, alocal circuit in which such lampis included, a relayin the main circuit for opening and closing the local circuit, an operators telephone Set at the central station, keys for connecting and disconnecting the operators telephone set with the line circuits, a lamp associated with each line circuit and indicating the key associated with such circuit, a local circuit including an alarm and a pilot light, asecond relay controlled by the first relay for closing the alarm circuit, a current generator at the central station for'actuating the bell and ringer at the substations, a trans arency at the central station associated with each line circuit and indicating the location of the substation with which operation of the audible signalfor closing the a such transparency is associated, a lamp for transparency lamp local circuit. V 7 1c illuminating the transparency and included In testimony whereof I afix my signature in a normally 0 en local-circuit, an audible I in presence of two Witnesses.

5 signal at the su stat-ion included in the line i v N. BANKS QREGIER.

circuit and actuated only upon the operation Witnessesi of the current generator at the substation on ARTHUR B. Snmotm.

such circuit and a contact actuated upon the J. MoRoBER'rs.