US2088002A - Automatic fire alarm system - Google Patents

Description

July 27, 1937. H. D. SCOTT.

' AUTOMATIC" FIRE ALARM SYSTEM Filed Oct. 5, 1954.

5 Sheets-Sheet l LOCd Z fnsfal'fafion SEarEin Point? GMM Q July 27, 1937. H. D. scorr 2,088,002

AUTOMATIC FIRE ALARM SYSTEM Filed Oct. 5, 1934 5 Sheets-Sheet 2 July 27, 1937. H: D. SCOTT,

AUTOMATIC FIRE ALARM SYSTEM Filed Oct. 5, 1934 5 Sheets-Sheets July 27, 1937. H. D. scoTT AUTOMATIC FIRE ALARM SYSTEM Filed Oct. 5, 1934 5 Sheets-Sheet 4 mm mm mm 8. m2

41. am wzmm @n a Q .3 S 3 E k E 3 a 0 Patented. July 27, 1937 PATENT OFFICE AUTOMATIC FIRE ALARM SYSTEM Hiram D. Scott, Bartlesville, kla., assignor of one-half to Frank M. Small, Bartlcsville, Okla.

Application October 5,

9 Claims.

This invention relates to improvements in fire alarm systems of the automatic type and the object thereof is to provide an arrangement to utilize the conventional equipment of panel dial systems to cause the automatic sending of a signal from a residence, factory or other point at which a fire originates to the fire station. 1

A further object of the invention is to provide an arrangement utilizing the wires of theconventional telephone system for indicating at the fire station the exact location of the point'o origin of the fire.

Another object of the invention is the provision of a system including a thermostatically controlled signalling device, which, at the initiation of a fire, is set in operation and through automatic dialing operations, first establishes a con-1 nection through the'telephone exchange into the. fire station and, after such connection has been. established, performs further signalling opera-i tions transmitted to the fire station at which point the incoming signal operates a related sig-, nal device to notify the fire station attendants of the location of the fire.

A still further object of the inventionis the provision of an automatic fire alarm system utilizing the wires of the conventional telephone sys-.

tem, but which does not interfere in the leasti with the normal operation of the telephone in, the residence, factory or other place where the system is installed.

With the foregoing objects outlined and other objects in view which will appear as the description proceeds, the inventionconsists in the novel features hereinafter described in detail, illustrated in the accompanying drawings,-and

more particularly pointed out in the appended electrical circuit at the local installation.

Fig. '3 is a front elevation partly broken away and in section of the signalling wheel device at the local installation.

Fig. 4 is an end view of Fig. 3. Fig. 5 is a partial plan view of a signalling device.

Fig. 6 is a longitudinal sectional view of the signalling wheel.

Fig. 7 is a vertical section on the line of Fig. 3.

1934, Serial No. 747,102

signalling wheel. Fig. 10 is a diagram of the electrical circuit at the fire station. I Fig. .11 is a front elevation of a modification of the signalling device.

Fig. 12 is an 'end view of the arrangement lO shown in Fig. 11. .7

Fig. '13 is an enlarged vertical section taken transversely through the feed screwand showingthe carriage. and relatedpart's in elevation.

Fig; 14 is ,a further enlargement in section through the feed screw and carriage-showing the adjustable feed member.

. Referring to the drawings in detail, and in particular .to the diagrammatic representation of the entire system illustrated in Fig. 1, A indicates the part of the device located at the residence, factory, plant or other structure in which thesystem is installed.- For convenience in fu-. ture reference; this part of the system will here-' inafterbe referred to as the .local installation.

B indicates diagrammatically the automatic exchange 'of a panel dial telephone system and C illustrates" the part of the system located at the firestation.

.The part of theapparatus constituting the local installation: is connected by branch conductors. l0 and II with the usual line wires 1 l2 and I3 leading from the exchange B to the local telephone set.l4. The conductor I0 is connected with the coil of a release magnet IS. The opposite 5" end of the coil of which latter is connected with one terminal of a thermostat l6 overa wire l1 and the opposite terminal of the thermostat is connected over a conductor l8 to one of the'ter-j 20. Normally the two contact members constituting the device 20 are in engagement with each other and the other terminal of the contact device 20 is connected with the branch conductor H.

The thermostat I6 is of the normally open type but upon occurrence of an abnormal temperature rise in the vicinity thereof, it operates to close and thereby connect the conductors l I and I8 and close the circuit over the branch conductors I0 and I I through the coil of the release magnet l5 and the contact device 20 and wheel 2 I.

It will be understood that a suitable type of thermostat will be selected and this is preferably so constructed as to close the circuit when the minals of contact device designated generally at 0 temperature in the room or other place in which it is located rises ten degrees in one minute or fifteen degrees in three minutes.

A manually operated switch 23 is shunted against the conductors l1 and I8 and is adapted for use in tes us the alarm system and for other purposes. 2

The arm ture 24 of the electromagnet i5 is pivotally mounted and cooperates with the signalling device to control the operation of the latteras will be hereinafter more clearly described. The terminal of the armature 24 is provided with a projection 25 cooperating with the contacts 26 and 21 whereby when the armature is attracted the projection 25 closes the contacts 25 and 21. The conductors 28 and 29 forming part of the electric supply system for the residence, factory or other place of installation, are connected, one with a transformer 30 and the other with the contact 26. The other contact 21 is connected with the other terminal of the primary winding of the transformer. The secondary winding of the transformer is connected over conductors 3| and 32 with a bell or other audible local alarm device 33 whichis thus automatically set in operation by the local current supply upon actuation of the armature 24.

The signalling device is preferably located in asuitable protective casing and includes a signailing wheel 35 coacting with the contact members 26 and 21 and controlled by the releasing armature 24 as will be hereinafter more fully described. In the embodiment of the invention herein illustrated the signalling wheel is driven by a spring motor including a supporting shaft 35a, a coil spring 351:, a ratchet wheel 35c and a pawl 35d. The ratchet wheel 35c isrigidiy secured to the shaft 35a but is rotatably mounted in bearings 35c provided internally of the wheel 35. One end of the spring 35b is fastened to the shaft 35a and the opposite end to the wheel 35 whereby when thespring is tensioned the latter acts to revolve the wheel 35. The shaft 35a is rotatably supported in a suitable frame 36 and the end of the wheel 35 opposite the ratchet and pawl device 35c, 35d is provided with a stub shaft 35] which is also rotatably mounted in the frame 38 and supports the wheel 35 for rotation therein. The stub shaft 35! is provided at its end with gear teeth 35!; meshing with a gear wheel 31 which latter is provided with a smaller pinion 33 meshing with the internal gear teeth 39 of a cam ring 40. At one point the rim of the cam i1ng 43 is interrupted as indicated at 40a and when the signalling device is in its normal or inoperative position as shown in Fig. 4, the angular arm 24a of the armature 24 is engaged in a recess40a andis held therein bym. spring-24b. The armature is pivotally mounted on the supporting frame 36 in operative relation to the magnet l5. Intermediate the gear wheel 31 and the pinion 33 a stop 4| is arranged which engages with the angular arm 24a and arrests the rotary movement of the signalling wheel 35 after the latter has made a predetermined number of revolutions as will hereinafter fully appear.

The. contact device 20 includes a relatively stationary contact member 20a and a movable contact member 241) both of which are secured to a supporting lever 42 pivotally secured at 42a to a carriage 42b slidably mounted on guide rods 420 secured in the supporting frame 36. A feed screw 42d is rotatably mounted in the frame 36 and the curved portion 42c of the lever 42 is threaded correspondingly with the screw 42d and is normally maintained in engagement therewith by a spring 421. When the lever 42 is swung downwardly against the tension of the spring 42f, the threaded portion 42c thereof is disengaged from the feed screw 42d and the carriage may be freely moved from end to' end of the guides 420.. The depression of the lever 42 also swings the contact member 201) out of -operative relation with the wheel 35.

Rotary motion of the signalling wheel 35 is transmitted to the feed screw 42d by gear wheels 43 and 43a whereby the carriage 42b is moved axially during rotation of the signalling wheel.

One of the purposes of the signalling wheel 35 is to send a number of impulses over the telephone lines I2 and I3 corresponding with the calling number of the fire station C and for. purposes of illustration, the number 300 has been arbitrarily selected. The impulses are produced by interruptions in the circuit when the contact members 2ila and 201) are separated and for this purpose the wheel 35 which is in the form of a hollow cylinder is formed externally with a plurality of groups of pins or projections arranged about a helical path the pitch of which corresponds with the pitch of the thread of the feed screw 42d. The pins are so arranged that as the signalling wheel revolves and the carriage 42b is moved axially thereof, said pins are successively engaged with the relatively movable contact member 20b and disengage the latter from the stationary contact 20a thereby interrupting the circuit.

A partial development of the helically arranged pins on the signalling wheel 35 are illustrated on the fragmentary lineal development of said wheel illustrated in Fig. 9. According to the selected number 300, three pins 44 are arranged in the first group and ten pins each in the two successive groups 45 and 43. Thus as the signalling wheel revolves and the telephone lines l2 and i3 are connected over the contact members 20a and 20b, first, three circuit breaks will occur as the pins of the group 44 engage the contact member 20b and the panel dialing system of the exchange B will respond by stepping up the selectors and connections three times. Thereafter, the selectors will be stepped across ten times by the pins 45 and again ten times by the third group of pins 46. The operation is the same as a person dialing 300 on an automatic dial telephone and in order to regulate the speed of the signalling wheel in accordance with the timing of the usual dialing operations of conventional systems, a suitable speed governor 41 is connected with the feed screw 42d.

Following the group of contact pins 46, addltional groups 48 and 43 are arranged onthe signalling wheel and the pins of these two last mentioned groups correspond with the identifying number of the residence, factory or other place at which the apparatus is installed It will be noted, however, that between the groups of pins 46 and 43 a relatively wide space 50 is provider. and this is of importance as it is designed to allow ample time for the ringing machine in the exchange to complete its cycle which is generally one ring every second and a half second interval between the rings. Unless the space 50 is of sufficient length the succeeding group of pins 48 and the circuit interruptions caused thereby would cause the selectors of the exchange to complete "300 and stack up.

For purposes of illustration a number 72 has been arbitrarily selected for the identification of at which the fire has originated, as will be here inafter more fully described.

At a point following the last group of pins, 49

a raised surface 5I is provided on the signalling wheel which engages the contact member 26a following the transmission of the two numbers 300 and "72 and opens the telephone circuit for a period sufficient to cause an interruption in the operation of the magnet I5 and during this period the entire telephone equipment restores itself to normal. During this period, all of the equipment at the fire station C is also restored to normal condition with the exception of the signalling device therein identifying the local installation at which the fire has started, as will hereinafter more fully appear. The signalling wheel 35 continues to operate, however, under the driving force of the spring 351) and the cycle of operation above described is repeated. For

this purpose a second series of groups of contact pins 44, 45,46, 48 and 49 and a further raised surface 5I are provided which effect a repetition of the calling and signalling operations. Four series of groups of pins and raised surfaces are preferably provided as this is the number of times which the conventional fire alarm system ordinarily repeats.

It will be understood that rotation of the signalling wheel 35 is initiated by the spring 3522 when the armature 24 is attracted incident to closing the circuit of the magnet I5 across the thermostat l6, the contact members 20a and 20b being initially in engagement with each other as illustrated in Fig. 2. Actuation of the armature 24 disengages the angular extremity of the arm 24a from the recess 40a and the stop 4| thereby permitting the signalling device to operate.

At the end of the four series of groups of contact pins 45, 46, 48 and 49 and the raised surface 5I an elongated raised surface 52 is provided on the signalling wheel which engages the contact member 20b and opens'th-e circuit for a longer period. The ratio of the gear wheels 35g, 36, 38 and 39 is so selected that when the contact member 20b reaches the terminal raised surface 52, the cam disk 40 has completed one revolution and the angular extremity of the arm 24 entering the recess 40a under the influence of the spring 241) engages the stop 4| which latter arrests the'rotary movement of the signalling wheel 35.

At the fire station the telephone wires 54 and 55 are connected with normally closed contact members 56-51 and 58-59, the current passing through said contacts over conductors 68 and GI to the slow release relay 62. A condenser 63 is interposed in the conductor 60 but, as will be understood, the ringing machine of the telephone system supplies alternating current and this current passes the condenser and operates the relay 62 whereas direct current will not pass said condenser. The alternating current energizes the relay 62 attracting the armature 64 and closing the contact pairs 65-66 and 61-68. The closing of the contact 6566 short-circuits the relay 62 over the conductors 69 while the closing oi. the contact6'I-68 closes-the circuit of a relay 18 connected by conductors 1| and 12 with a local current source 13. The relay 62 is of the retarded type and therefore affords ample time to assure actuation of the relay 10. The armature .14 of the relay 10 actuates a group of contact members designated at D in which the contact members 56 to 59 are included. Upon actuation of the set of contacts D, the contact members 15 and 16 close a circuit from the positive pole of the current source 13 over the restoring button 11 through a conductor 18 to the conductor 18a, contact members 15 and 16 and over a conductor 19 to the conductor 12, relay 1Il, conductor 1I,

thereby locking the relay 18 in energized condition. The contact member 58 cooperates with a contact member and the contact member 56 cooperates with contact member 8| when the group of contacts D is actuated and in this manner a circuit is closed from the conductor 54 over the contact members 56 and 8|, conductor 82, one side of condenser 83, the coil of the relay 84, conductor'85,.other' side of condenser 83, contact members 80 and 58 and the conductor 55. The relay 84 acts as a receiver with condenser 83 in parallel with the winding thereof and it does not operate until the groups of pins 48 and 49 pass the contact member 28b, but when the.

current is interrupted by the passage of the said pins the armature 86 of the relay 84 is actuated, first, seven times as the group of pins 48 passes thereby causing: the selector 81 to step up seven times and, when'the two contacts 49 pass the contact member 29b the selector 81 steps across two times. The impulses are transmitted to the selector 81 in response to those received by the relay 84 over a conductor 88 and a pair of contacts 89 which are actuated at each attraction of the armature 86, a conductor 90, a resistance 9I, a pair of contacts 92 which are closedwhen the group D is operated and a conductor 93 leading back to the selector 81. This operation of he selector establishes the circuit 1-2 in accordance with the number of impulses received over the selector 81 and the connector 94.

The circuit identified as 12 in the fire station is the one which includes the visible signal on the switch board associated therewith. When the conductors 95 and 96 are closed through 'the connector 94, the following circuit from the positi c pole of the local source of current 91 is clos d, conductor 95 including'the'resistance 95a, co nector 94, conductor 96, relay coil 98 and conductor 99 to the negative pole of the current source ,91. The closing of this circuit energizes the relay 98 and the contact members 98a thereof being closed a second circuit from the conductor 99 overthe contact members 98a to the coil I of a second relay and over the conductor IOIa to the negative pole of the current source 91 is completed. The ,relay I80 is energized and the contact members I92 thereof are moved into contact and another circuit leading from the positive pole of the current source over the conductors and 96 through the contact members 9811, relay coil I09, contact members I02 and conductor I03 to the conductor Illla leading to the negative pole of the current source is completed.

The line lamp constituting the fire station indicating device IN is interposed in the conductor IIlIa and is illuminated when the circuit of this conductor is closed, while the pilot lamp I84is interposed in the conductor I03 and .is lighted when the circuit over this conductor is closed.

In this manner the line lamp IOI on the indicating board at the fire station related to the signalling wheel 35 which has been set in operation by the release of the associated thermostat I6 as well as the pilot I04 are illuminated. In order to restore the circuit to-normal the restoring button 11 is manually actuated thereby interrupting the circuit of the relay 10 and permitting all of the contact members of the group D to return to initial position,

An audible alarm device I I0 is located at the fire station and is supplied with current from a local source III over conductors IIOa and H01) when the two contacts II2 are engaged as when the armature I4 is attracted.

As stated in the foregoing when the signalling wheel moves to a position where the contact members 20a and 201) are separated by the long raised surface 5|, all equipment in the telephone oillce is restored to normal, but the calling operations are repeated three more times owing to the provision of the multiple series of groups of pins 45, 40, 40, 49 and the raised surfaces 5|. When the contact member 20b reaches the final raised surface 52, the disc willhave completed one revolution and the magnet I5 being de-energized permits the arm 24a to enter the recess 40a and engage and arrest the stop 4|.

r Referring to the modification of the invention illustrated in Figs. 11 to 14, the signalling wheel 35 corresponding in construction to that above described, is supported on a shaft I 2I geared by a-worm and worm wheel I22 with the shaft I23 of a speed governor I24.

The shaft I2I is driven from a spring motor I30 actuating a gear wheel I25 through a train of gears I26, I21 and I23.- The release magnet I5 is the same as that above described in connec tion with Fig. 1, and the contacts 26 and 21 controlling the local alarm 33 are also the same and the detail :description thereof will not, therefore, be repeated. In the modification, however, an armature lever I24a is pivoted at I20 and provided with a recess 'I3I normally coacting with the pin I32 on the gear wheel I26 to lock the drive mechanism for the signalling wheel I20 against operation prior to a fire. In the case of the construction described, the ratio of the gear wheels I26 to I20 is suitably chosen whereby the pin I32 enters a second recess I33 after the complete operation of the signalling device and the drive mechanism is thereby arrested.

The conductors II and I0 (Fig. 2) are connected respectively with spring contact members I34 and I35, which latter in their normal position engage one another and thereby close the circuit across the conductors II and I0. The members I34 and I35 are supported in a holder I36 pivotally mounted on a shaft I31 supported on posts I33 fixed in the carriage I39. The holder I36 is provided with an arm I40 having a knob-like end and also a spring I. a

The carriage I33 isprovided with a bore I42 which is slidably mounted upon the feed screw I43 which latter is extended at one end to form the supporting shaft for the gear wheels I26 and I21. The movement of the carriage I39 is con-- fined by a suitable guide I44 engaging recesses provided in the carriage.

The feed shaft I43 is provided with two sets of screw threads I45 and I46, the first being adapted to eflect the feed movement of the carriage during the operation of the apparatus and the other thread, which is of steeper pitch, being 7 adaptedto eflect the rapid return of the car I iage,

the two threads being oppositely pitched. The carriage I39 is provided with a spring-actuated pin I41 having a handle I48 at the outer end thereof and a thread-e member I43 at the inner end. The medial portion of the threadengaging member I49 is provided with a projection I50. The return thread I46 is of greater depth than the said thread I45 and when the pin I41 is adjusted to engage the thread-engaging member I49 therein, the carriage, due to the pitch of the thread I46 and the direction of rotation of the shaft I43, is-returned to its initial position at the left end of the screw. In the normal position of the apparatus, that is to say, when it is set for operation in response to the outbreak of a fire, the pin I41 is adjusted by means of the handle I48 so that the projection I50 engages in shallow groove of the feed screw I43.

Immediately above the guide I44 2. guide rail I5I is located and at the ends thereof curved guide arms I52 are arranged. In moving from right to left during the return movement of the carriage I 30, the arm I40 slides along the top of the guide rail I5I retaining the pivoted brush holder I36 together with the contact members I34 and I35 in upwardly tilted and inoperative position out of contact with the pins of the wheel 35. However, as the arm I 40 engages under the left hand curved guide member I52 it is depressed thereby and engaged beneath the guide rail I5I which latter during the feed movement of the carriage, tilts the brush holder I36 into operative position, the spring I 4I being retained in compressed condition. When the carriage has completed its movement toward the right, the spring pressing against the top of the guide I44, lifts said arm from under the curved guide rail I5I and thereafter the springs rest on top of the rail I5I for return of the carriage to initial position.

At the initiation of operation of the modified construction the electromagnet I5 is energized the same as in the construction first described upon the occurrence of a fire and upon actuation of the arm I24a, the pin I32 is released and the drum wheel I20 is set in operation by the spring motor I30. Under these conditions, the contact holder I36 being depressed by engagement of the arm I40 under the guide rail I5I, the finger I51 of the upper contact member I34 is disposed in the path of the pins of the signalling wheel 35 and actuated thereby.

At the end of the travel of the carriage, the thread-engaging member I49 coacting with the return thread I46 returns the carriage to initial position at the left end of the cylinder but in the reversal of movement of the carriage at the right end of travel, the arm I40 passing the end of the rail I5I is raised by the spring I and the contact holder I36 is tilted upwardly to inoperative position. As the carriage comes to its initial position at the left end, the contact holder is drawn downwardly to operative--position by engagement of the arm I 40 with the guide I 52 but the break strip I55 engaging the finger I40 separates the contact members I34 and I35 thereby restoring the circuit I0-I I to open condition.

It will be understood that the governor I24 is so adjusted as to regulate the speed of the signalling wheel 35 that the impulses produced by the actuation of the contact members I34-I35 isin accordance with that of conventional telephone systems a It will also be understood that the ratio of gearing of thegear wheels I25 to I28 is such that the wheel 35 revolves throughout a period corresponding in time to that required by the movement of the carriage I 33 from left to .right and to its return position beneath the guide I52 at which point the pin I32 enters the recess I33 and move- M) ment of the wheel is arrested with the break strip I55 engaging the finger I51 and retaining the circuit Ill-ll in open condition.

A structural point of importance to be noted in connection with both forms of the invention consists in that at the conclusion of the four repetitions of the signal produced by the signalling wheel, the latter comes to rest at a point where the contact members associated with the wheel 35 are separated one from the other, and thus the circuit across the branch conductors l and II is left open and the telephone M at the local installation is in condition for service use. This is accomplished in connection with the form of invention first described by arresting the'movement of the wheel 35 when the raised strip 52 is disposed on the contact member 201).

In the second form of the invention this purpose is served by the relatively long strip I55 at the left end of the wheel which engages and lifts the finger i! when the contact holder is restored to initial position.

From the foregoing it is believed that the construction, operation and advantages of the invention may be readily understood by those skilled in the art, and it is apparent that changes may be made in the details disclosed; without departing from the spirit of' the invention, as expressed in the claims.

What I claim and desire Patent is:

1. In an automatic fire alarm system, a local installation, a fire alarm station, a panel dial telephone system, said telephone system including telephone lines leading to the local installation and to the fire station and an automatic exchange adapted to connect the two lines in response to signal impulses sent thereover, said local instalto secure by Letters laticn including a motor-operated signalling device, thermostatic-ally controlled release means associated with said signalling device, and means actuated by said signalling device to connect the.

lines leading from the local installation with the exchange and to transmit the calling signal of the fire station-whereby to establish 'a'connection over said lines from said local installation through the exchange to the fire station, said signalling device including a rotatable wheel having two series of signalling elements thereon, the first series corresponding to the signal of the fire station and the second series corresponding with the identifying signal of the local installation, and a relatively wide space between the several series of signalling elements adapted to afiord a relatively long tiineinterval between the termination of the sending of the first series of signals and the initiation of the sending of the second series of signals.

2. In an automatic fire alarm system, a local installation including telephone lines of a panel dial telephone system, a motor driven signalling wheel, a thermostatic device and means actuated in response to operation of the thermostatic device to connect said telephone. lines with said signalling wheel and to release the latter whereby it may be operated by the motor drive, a plurality of series of signalling elements distributed over the circumference of the signalling wheel, a relatively wide space between the several series of signalling elements aiiording a sufficiently long time interval therebetween to permit the standard ringing machine of said telephone system to function in the normal manner and to then restore a local installation, a fire alarm station, a panel dial telephone system, said telephone system including telephone lines leading to the local installation and to the fire station and an automatic exchange adapted to connect the two lines in response to signal impulses sent thereover, said local installation including a motor operated signalling device, thermostatically controlled release means associated with said signalling device, means to connect the lines leading from the local installation with the exchange, said signalling device including a rotatable element having two series of signalling members thereon, the first series corresponding to the signal of the fire station and the second series corresponding with .the identifying signal of the local installation, the several series of signal members being relatively arranged on the rotatable element to afford ,a time interval between the termination of the first .series of signals and the sending or the second series, whereby the ringing equipment of the automatic exchange may restore itself to normal.

4. In an automatic alarm system, a local installation including telephone lines leading through an automatic telephone exchange to an alarm receiving apparatus, said local installation including a signalling element, means for setting said signalling element in operation and for connecting said signalling element to said telephone lines, said signalling element including two series of signalling members, said series being so spaced from each other as to aiford a time interval therebetween suflicient to permit the standard ringing equipment of the automatic exchange to restore itself.

5. In an automatic alarm system, a local installation including telephone lines leadinga connection from said local installation through said exchange to said receiving apparatus, a second series of signalling members adapted to transmit the identifying signal of said local installation directly to said receiving apparatus,

said first and second series of signalling members being so spaced from each other as to afford a time interval therebetween sufiicient to permit the standard ringing equipment of said exchange to restore itself.

6. In an automatic alarm system, a local inthrough an automatic telephone exchange to a receiving apparatus, said local installation including a signalling element, means for setting said signalling element in operation and for connecting said signalling element to said telephone lines, said signalling element including a first series of signalling members adapted to establish a connection from said local installation through said exchange to said receivingapparatus, a second series of signalling members adapted to transmit the identifying signal 'of said local installation directly tosaid receiving apparatus, said first and second series of signalling members being so spaced from each other as to afford a time interval therebetween sufficient to permit the standard ringing equipment of said exchange to restore itself and automatic means cooperating.

with said receiving apparatusresponsive to said stallation including telephone lines leading first series of signalling members whereby said receiving apparatus is put in condition to receive and register said identifying signal transmitted by said second series of signalling members.

'7. In an automatic alarm system, a local alarm mechanism connected by telephone lines to an automatic telephone exchange, a standard'ringing machine cooperating with said exchange, telephone lines leading from said exchange to an alarm receiving apparatus including a relay cooperating with said receiving apparatus and actuated by said ringing machine to complete a circuit over said telephone lines from said local mechanism to said receiving apparatus.

8. In an automatic alarm system, a local alarm mechanism including telephone lines leading through an automatic telephone exchange to an alarm receiving apparatus, a standard ringing machine cooperating with said exchange and said receiving apparatus, said local mechanism including a signalling element, means for setting said signalling element in operation and for connecting it to said telephone lines, said signalling element including successive series of signalling members, said series being so spaced from each other as to aflord a time interval therebetween suflicient for said ringing machine to function in the normal manner and to then restore itself, a relay actuated by said ringing machine to establish a-circuit including said local mechanism and said receiving apparatus.

9. In an automatic alarm system, a local alarm mechanism connected to the telephone lines of an automatic telephone exchange including a standard ringing machine and thence to an alarm receiving apparatus, said alarm mechanism including a first series of signalling members adapted to establish a connection from said alarm mechanism through said exchange to said receiving apparatus, a second series of signalling members adapted to send signals to be registered by said receiving apparatus, a space between said first and second series of signalling members of such length as to permit said ringing machine to function in the normal manner and to restore V itself prior to the transmission of said second series of signals, a relay cooperating with said receiving apparatus and actuated by said ringing machine to establish a circuit over said telephone lines including said alarm mechanism and said receiving apparatus over which said second series of signals may be transmitted to be registered by said receiving apparatus.

HIRAM D. SCO'I'I.

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