US2905762A - Fire and burglar alarm system - Google Patents

Description

Sept. 22, 1959 w, E E ETA L 2,905,762

FIRE AND BURGLAR ALARM SYSTEM Filed April 10, 1957 3 Sheets-Sheet 1 Fig- INVENTORS' Se t. 22, 1959 I e. w. RETTIE ETAL 2,905,762

FIRE AND BURGLAR ALARM SYSTEM Filed April 10, 1957 5 Sheets-Sheet 2 Fag-L 5 RELEASE Sept. 22, 1959 Filed April 10, 1957 3 s Sheets-Sheet 3 29 In 35 4;[ J F I [13 1 I/ L lJ f AMPLIFYING I 1 59 I mscammmm I I 22:2 [7 l 66 cmcun' M TELEPHONE LINE T0 HAND SET AND EXTENSWNS AUDIO INPUT FIRE AND BURGLAR ALARM SYSTEM George W. Rettie and Robert D. Hotchkiss, North Miami Beach, Fla.

Application April 10, 1957, Serial No. 651,885

6 Claims. (Cl. 179-5) This invention relates to new and useful improvements in alarm systems.

Generally, it is the object of the present invention to provide an alarm system which is set in operation by the closing of one of a plurality of normally open switches which sends a super-sonic signal to a control panel, centrally located in the building, which transmits, in a novel manner, a recorded language message by means of an endless magnetic tape player, a dialing mechanism and the telephone lines, from the building protected by the system to the ofdce of a patrol service or direct to the police, advising the person receiving the message of the address of the alarm and whether an attempted illegal entry is taking 'place or whether there is a fire in the building.

It is also an object of the present invention to provide an alarm system which transmits super-sonic signals from the protected openings to a control panel centrally located in the building and thereby eliminates wiring between the protected openings and the control panel.

It is also an object of the present invention to provide an alarm system to protect a building from illegal entry by mounting the insect screens covering the doors and windows so that pressure against the screens from the outside, exerted by persons attempting illegal entry, will close one of a plurality of normally open switches that activate a solenoid which transmits a super-sonic signal to a control panel centrally located in the building, thereby setting the burglar alarm sequence of the system in operation.

It is also an object of the present invention to provide an alarm system having normally open, thermostatically controlled switches at strategic locations for fire detection which, upon the occurrence of an excessive temperature rise, will close and activate a solenoid which transmits a super-sonic signal to a control panel centrally located in the building, thereby setting the fire alarm sequence of the system in operation.

It is also an object of the present invention to provide an alarm system having audio-receiving, amplifying and discriminating circuits tuned to close relays in response to super-sonic signals of two specific frequencies, one transmitted when one of a plurality of normally open switches at doors and windows of the building is closed, due to illegal entry, thereby setting the burglar alarm sequence of the system in operation, and the other transmitted when normally open, thermostatically controlled switches, located at strategic points throughout the building, are closed, due to an excessive temperature rise, thereby setting the fire alarm sequence of the system in operation.

It is also an object of the present invention to provide a telephone dialing mechanism which can be set to dial and establish a connection with any desired telephone number and be so connected to the telephone line that it does not interfere with the normal operation of other phones on the line, except when the alarm system is set in operation all other telephones and extensions on the line are disconnected to prevent any interruption of the transmission of the recorded message.

It is also an object of the present invention to provide an endless magnetic tape recording mechanism and amplifying circuit to transmit, by telephone, the appropriate message of two messages recorded on a single tape advising the person receiving the message of the address of the alarm and whether an attempted illegal entry is taking place or whether there is a fire in the building.

It is also an object of the present invention to provide an alarm system, the cost of which will be reasonable because, it uses a conventional telephone line, offers protection from unauthorized entry through door and window openings covered only by insect screening without installing costly steel grills or other additional protection, requires no wiring between the protected openings and the control panel, and can be installed in residencesor commercial buildings by the householder or by a private patrol service organization.

For further comprehension of the invention, and of the objects and advantages thereof, reference will be had to the following description and accompanying drawings, and to the appended claims in which the various novel features of the invention are more particularly set forth.

In the drawings accompanying and forming a part of the specification and in which like reference numerals designate corresponding parts throughout:

Fig. 1 is a diagrammatic view showing thet alarm system of the present invention.

Fig. 2 is a partial enlarged horizontal section view of a switch which can be used with the alarm system, taken on the line 22 of Fig. 1.

Fig. 3 is a partial enlarged horizontal section view of a switch which can be used with the alarm system, taken on the line 33 of Fig. 1.

Fig. 4 is an elevational view of the burglar alarm transmitter with the cover removed.

Fig. 5 is an elevational View of the fire alarm transmitter with the cover partially removed.

Fig. 6 is an elevational view of the control unit.

Fig. 7 is a view of the control unit from the underside with the bottom panel partially removed.

Fig. 8 is a schematic wiring diagram of the alarm system.

Referring to the drawings in detail, and particularly to Fig. 1, there is illustrated a portion of the interior of a building 10 showing a hinge mounted door 11 which has a large opening with pivotally mounted, glass louvers 12 which cover the opening on the outside and can be opened and closed from inside the door by a crank 13. The opening in the door 11 is covered on the inside by a conventional metal framed screen 14 held in place against the metal casing 15 by a plurality of tabs 16 and bolts 17, more fully illustrated in Fig. 2, bolted into the metal casing 15 which is fitted into the opening and fastened to the door. The door 11 is provided with a conventional door knob 18 which contains a lock mechanism for locking the door in a closed position by depressing the plunger 19 in the center of the knob on the inside of the door. With the plunger 19 in the depressed position, the door 11 can only be opened from the outside with a key, but can be opened at any time from the inside by turning the knob 18 which releases the plunger. Since the opening in the door 11 is covered only by pivotally mounted andeasily removable glass louvers 12, illegal entry is easily accomplished by either removing or breaking a panel of glass and forcing or cutting an opening in the screening 20 and turning the knob 18 on the inside of the door which releases the plunger 19. It is evident that this arrangement is very vulnerable to illegal entry. Although the alarm system of the pres ent invention is designed to give protection to all types of doors, this particular. type. ofi=door represents the most difiicult type to protect from illegal entry and is chosen to illustrate a type of switch, generally indicated as 7 (see Fig. 2) which can be used to set the alarm system into operation.

In Fig. 2 is shown, insectionalview, a: conventional rectangular metal frame 14, overwhich. themetal insect screening20 is. stretehed,.held againstthe. metal casing;

14, until'pressure. exerted againstthe screeningg20 from:

the outside further; compresses the rubber grommet 22,- and'is locked'in this. position by the jam-nut 25, thereby creatinga normally openswitch generalyindicated as 7.

Fig.. 3 shows a variation of the mounting; in which the metal'casing 26 is of different structural form than: the metal casing 15 shown-in. Fig. 2 andrequires that a spacer 27"be usedb'etween the rubber grommet 22 and the tab 16 in order that the screen frame28 be held-in.

place against the metalcasing 26 by pressureof the tab onthe rubber grommet. It is apparent that variations of this kind can be made for any type casing in order to provide. that a screen framebe held in. position against,

but insulated from, a metal casing by pressure through a plurality, of rubber grommets-thereby creating a plurality of normally open switches generally indicated as. 8 so that pressure exerted against the outsideofthe screening, such as is required in attemptingto enter the building by forcing or cutting the screen, would resultin. theclosing of one of theplurality of normally open switches. It is also apparentthat any-other door than the.type.illustrated could be protected by switches, already patented which provide a contact of a normally openswitch as a result of an attempted'entry, to. set thealarm system in operation.

A burglar alarm transmitter 29' is. mounted onthe door (see Fig. 1) and is shown without the. cover in Fig. 4. The transmitter 29 contains a solenoid 30. onwhichis bolted a plate 31 which has been lancedto. provide a tongue 32 having a hole through which a bar. 33 is free to slide. On one end of the bar 33 is mounted, by means.

of a spring blade 34, a small hammer 35 and the other endjis bent at-a right angle so as to be. engaged with a notch 36:: in the trigger arm 36 which is pivotally connected by the pin 37to the armature 38. The. bar 33- also passes through and is free to slide in.a hole. in the center of a plate 39, which is riveted to the end. of plate 31, and through which there is a hole of greater diameter thanthe diameter of the tuning rod 40. A similar hole in the end of plate 31 is matched with the hole in plate 39 andtwo spring steel pins'41 are locked 'in grooves in the faces of plate 31 and plate 39'when theplates are rivetedfitogether. The tuning rod 40 is held in. a resilient manner and 'is free to vibrate between the spring steel pins 411in a groove in the tuning. rod 40, the. bottom diameter of which is less than the space between the pins. The tuning rod 40 is of aluminum. and of such diameter andlength as to transmit a super-sonic signal of specific frequency when struck by the hammer 35. with a-forcedeterrniued by the spring 42 and. the distancethe bar 33 is caused to travel when triggered'by the action of the solenoid30. A series circuit, created by the lead 43 between the screen frame 14(see Fig. 1)and the positive of'th'e battery 44, a common strip- 45. between the negative ofbattery 44 and the positive of battery 46; a lead casing -,lis..closed.by theclosing of any of the switches.

generally indicated'as'Tand 8 and causes the armature 38 of the solenoid 30 to pull in. When the armature 38 is pulled in by the solenoid 30, the trigger arm 36 is forced down against the spring 49, by contact of the inclined notch 36b in the trigger arm 36 with the top of the slot in plate 39, so that the bar 33 is released from contact with the notch 36a in the trigger arm 36 and is free to re-coil until the stop-pimSlt in bar 33 contacts the plate 39. When the bar 33, impelledby the spring 42, is stoppedby'the pin'StY, th'emomentumoftlrehammer 35 flexes the. spring'blade- 34' and permits the hammer 35 to strike the tuning; rod 40; but the stop pin 50 is set so the hammer. 35 cannot remain in contact with the tuning=rod 4t)"a11d after"beingstruck by the'hammer 35, the rod 40 is free to vibrate-. When the circuit is opened by the opening of all the switches 7 and 8, the spring 51 on the armature 38 forces the armature 38 to travel in a lengthwise direction until the inclined end 360- ofthe trig-ger'arm36 contacts the bentendof bar 33 which forces the trigger arm 36 down against the spring 49until thebent end-ofbar 33 :re-enters the notch 36aand the trigger arm' 36'is'forced by. the spring, 49 intocontactwith the plate 39"at the inclined notch-36b. and is thus-cocked-for the next cycle. The specific frequency and length of time of vibration of the tuning rod 40, when struck inthe manner described, isrequired to assure that-only the signal emitted-by atuning rod40. in a burglar alarm transmitter 29 will set'the burglar alarm sequence-of the system'in operation, as: willbe more ful-lyexpl-ained in=describing the audio circuits.

The portionof a. building, was showni'n Fig. lis also provided with awindow 52 having; pivotally' mounted awning type glass panels 53 which cover the outside; and can be opened andclosed-from the inside by turning the crank 54 The window'52 is covered on' the inside byv a conventional metal framed screen 28' held in placeagainst the metal casing 26 by a plurality of tabs 16 and boltsSS; more fully illustrated itrFig. 3, bolted into the metal casing 26-which isv fitted intothe opening and fastened to the building. Mounted overthe window 52 is one of the burglar alarm transmitters: 29,1already'describedin Fig; 4, connected in-series by a lead -56--connected. to the screen frame. 28' and by -a lead 57 to the metal casing 26"- so that theclosing-of-any; oneoftheplurality of switches generally- -indicated at 8 see Fig. 3) as a result of pressure exerted againstthescreen SS frOnL-the outside, such as: would be requiredto. cut;- or force an opening 'in 'the' screening 58, would result in the transmission,. bythe tuningrod 40= -in th'e:transmitter 29; ofra super-sonic signal as already described. It is -apparent that any other.

window than" the type illustratedrcould be: protected by: switches, already: patented which provide a contact ofa normallyopen switch as .a; result of an attempted entry, to set the alarm systemin operation. Although the'alarm system of the present-invention is designed to give pro tection to all types of windows, this-particular type of window is;illustrated as itrepresents; the most diflicult type to protect, particularly: since'itis oftenopen when" protection against entry'is desirable.

Also in Fig. 1, there 'is mounted onthe wall over the; door 11, one of a plurality of fire alarm transmitters 59, which are placed at strategic locations for the detection throughout the building, containing batteries:60 and 61? (see Fig. 5 and a solenoid=62 whicharewired-in series through -abi-metal-strip 63'whichcloses the contacts 64* and65 and energizes the solenoid 62 whenever an=-excessive rise in temperatureoccurs such as-dueto a fire: The-action of the solenoid 62; is identical with that which was described when the solenoid 30 is activated inthe burglar alarm transmitter 29. However, .the tuned-lrod 66 in the fire alarm transmitter 59 is of different length than the tuned rod 40in theburglarm alarm transmitter 29- andtransmits. a super-sonic signal of different fre q y han thesignal transmitted by-the tuned rod-40 in the bnrglar'alarrn transmitter. The specific frequency and length of time of vibration is required to assure that only the signal emitted by the tuned rod 66 in the fire alarm transmitter 59 will set the fire alarm sequence of the system in operation as will be more fully explained in describing the audio circuits.

In Fig. 1 the control panel 70 is mounted in a box 71 which is placed in some convenient central location in the building such as a closet. The microphones 72 which are used are designed for response at super-sonic frequencies and are so located in the building as to receive the supersonic signals from the transmitters 29 and 59. The cable 73 carries these signals to the amplifying and discriminating circuits in the control box 70. These circuits are tuned and balanced so that only the signal emitted by the tuned rods 40 in the burglar alarm transmitters 29 will close the burglar alarm circuit and only the signal emitted by the tuned rods 66 in the fire alarm transmitters 59 will close the fire alarm circuit. It is not intended to include the amplifying and discriminating circuitry in the patent and no detailed description will be given. However, the tuned amplifier, amplitude limiter, balanced discriminator and integrator network, assure that only the signal emitted by the fire alarm transmitters 59 will initiate the fire alarm sequence and only the sig nal emitted by the burglar alarm transmitters 29 will initiate the burglar alarm sequence. The possibility of a false alarm is practically eliminated because of the frequency rate characteristics of extraneous noise.

On the back of the control panel 70 as shown in Fig. 7, is mounted a dial motor 80 which has a gear train to reduce the speed to approximately one revolution per minute of an output shaft 81, which protrudes from the front of the control panel 70 (see Fig. 6), and on which is mounted a dial plate 82. Near the outer periphery of the dial plate 82 are 120 holes 83 at 3 degrees into which metal pegs 84 can be pressed which protrude from the underside of the dial plate to act as teeth to contact the gears 85 on a dialing mechanism 86 which is the standard telephone mechanism installed in a telephone hand set. The normal dialing disc which has finger holes at 30 degrees has been replaced by the gear 85 which has a spacing between teeth of 30 degrees so that each tooth on the gear represents one of the finger holes of the original dialing disc. The dialing mechanism 86 is mounted on the front of the panel 70 with the center of the gear 85 as such a distance with relation to the center of the dial plate 82 as to provide perfect mesh of the 12 tooth gear 85 with the pegs 84 which protrude from the underside of the dial plate v82. On the face of the dial plate 82 is a hole marked for the first peg 87. Starting at this hole 87, the reason for which will be explained later, any number of pegs upto ten can be installed in sequence in a counter clockwise direction to provide that clockwise rotation of the dial plate 82, when the dial motor 80 is energized, will cause the gear 85 to be rotated the number of degrees required so as to transmit the same number of impulses as would have occurred if the dialing mechanism 86 had been equipped with a conventional dialing disc and had been rotated manually by inserting a finger in the hole for the number desired. Each sequence of pegs represents a digit of the telephone exchange and number of the telephone subscriber with whom it is desired to establish a connection. In order to permit time for the dial mechanism 86 to recoil and transmit the impulses, holes 83 must be left open between each sequence of pegs 84. The number of holes which must be left open depend upon the number of pegs in the previous sequence, thusly, following a sequence of pegs, 6 holes must be left open, following a sequence of 6 pegs, 5 holes must be left open, following a sequence of 3 pegs,4 holes must be left open, and following a sequence of 2 pegs, 3 holes must be left open. The reason for the variation of the number of holes left Without pegs is to assure as rapid completion of the dialing of a given number as possible. The dial plate in the illustration has pegs positioned to dial YUkon 9-0639.

Adjustably mounted on the dial plate 82 by means of slotted holes and bolts 88 is an arm 89 having on its extreme end, at right angles to the surface of the dial plate, a roller 90 which, when the dial plate is rotated, contacts the leaf 91 of the switch 92 and the leaf 93 of the switch 94- so that it will open and close the circuits which these switches control. Also mounted on the back of the control panel 70 is a tape player motor 95 having a gear train, the output shaft 96 of which protrudes above the face of the panel 70 and which turns at a speed which gives the shaft 96 a periphery rate of 1% inches per second which is considered a minimum speed desirable for driving a magnetic tape. Also mounted on the face of the control panel 70 is a pinch arm 97 rotatably mounted on bolt 98 on which is mounted a rubber roller 99 which rotates on bolt 100. Connected to the arm 97 through a spring 101 is a solenoid 102 which when energized pulls on the spring 101 to cause the rubber roller 99 to contact the output shaft 96 of the tape player motor 95. Spooled between the shaft 96 and the rubber roller 99 and around the mountings 103 and passing between the faces of tape head 104 and tape head 105 is an endless belt of magnetic tape 106. When the solenoid 102 is energized and the tape player motor 95 is energized, rotation of the shaft 96 causes the magnetic tape to be driven and to rub on the faces of the tape head 104 and the tape head 105. The tape head 104 is adjusted so that its contact point is aligned with one half the width of the magnetic tape, while tape head 105 is adjusted so that its contact point is aligned with the other half of the width of the tape. The length of tape 106, which can be varied by the positioning of the mounting posts 103, has been set in this version of the invention at a length which is adequate to provide only the recording of the desired message, and no more, so that repetition will occur with as little delay as possible.

Mounted on the face of the panel 70 is a release momentary switch 107, which is Wired in its normally closed position in series with one side of the input power supply 108, and which, when pressed, releases all of the relays and clears the panel.

Also mounted on the face of the panel 70 is a set momentary normally open switch 109, wired in series with the dial motor 80 which, when pressed, provides a direct circuit from the input current through the dial motor so that the dial plate 82 can be re-set to a starting position where the arm '89 on the dial plate has passed switch 92 to assure that when the alarm system is set in operation, the closing of relays and dialing will occur in the proper sequence.

Also on the control panel 70 is a ratchet gear rotatably mounted on bolt 111 so that roller 90 on arm 89 on the dial plate 82 will contact one of the teeth of ratchet gear 110 during each cycle of dialing. Mounted on the post 112 is a flat steel blade 113 having a spring 114 exerting pressure so that the blade 113 presses against the teeth of the ratchet gear 110 holding it in a static position between cycles of rotation caused by the roller 90 on the arm 89. The tooth 115 has an elongation, which contacts the leaf 116 on the switch 117 which is wired in series with the input current to the panel, so that, when the ratchet gear 110 has been rotated by sufficient cycles of the dial plate, the tooth 115, on ratchet gear 110, contacts the leaf 116 of the switch 117 and the circuit of the input current is broken, clearing the panel by releasing the relays. This method of limiting the recycling of the dialing mechanism to a given number of cycles, as determined by the number of teeth on the ratch et gear 110, is to overcome objection of the telephone company to any use of the telephone lines which keeps. the telephone equipment in use beyond a reasonable periodv of time. The gear 110, having six teeth, would, if tooth 1'15 were set at the position shown when the alarm sys- To assist in proper setting'o-fthe' dial plate 82', a pilotv light 118 is mounted through the control panel'with its bulb under the dial plate 82 ata pointwhere'a hole 119' in the dial plate makes the light visible only when the arm 89 is set in theproper-positioni This pilot light 118, which is wired in'parallel with the input currentsupply, in addition to assisting in re-setting the dial plate 82 to the proper starting point, also indicates, when it is lit, that current isreaching the panel.

Also mounted on the back ot'thecontrol panel is the pre amp chassis 120. and the relays 3, 4', 5', and'6, which are involved in the circuitry and more fully. described later.

Also mounted'in the box '71 is a chassis 125 containing the amplifying anddiscriminating circuits and on .which are mounted relays 1 and 2 and delay relay 127, andv a chassis 126 on which are mounted the transformer and rectifier unit which supplies power for these circuits.

Referring now specifically to Fig. 8, when one of a plurality of switches 7 'is closed; by an attemptedillegal entry, the solenoid 30 in burglar alarm transmitter 29 is energized, causing the hammer 35 on the armattu'e, 38 of the solenoid to strikethe tuning rod 40 which vibrates andtransmits a super-sonic signal which is received by one of the microphones 72 and fed'to the. amplifying.

and discriminating circuit, causing current to flow through the control tube 74 to the coil of the burglar alarm relay 1, closing the contacts In and 1b and feeding the input current from the power supply line 10'8fto the coil of relay 3, closing contacts 3a and 3b which feeds current directly to the coil of relay 3, so. that.relay S'remains energized after the contacts 1a and 1b open on the burglar alarm relay 1. With the-coil of relay 3'.energized, contacts 30 and 3d are held closed andinputcurrent is, fed to the coil of relay 5, to the normally closed contacts 92a and 92b of the switch 92 and=througha normally closedmomentary switch 109 to: the dial motor 80, to. the normally open contacts ofv the delay relay 127, to the tape player motor 95, to the solenoid 102,

and to the pre amp 120 circuit of the tape-player. With coil-of relay 5 energized, connectionbetween contact 5a and'contact 5b is-broken, disconnecting the telephone line 128. from connection with telephones and extensions in the building and" connection is: made betweencontact 5b and contact 5c thereby closing a circuit between line 128 of the telephoneline and the terminal 86a of the dialing mechanism 86. Energizing the coil on-relay 5 also closes-contacts 5d and 5e, closing a-circuit-between line-129 of the telephone line and the preamp circuit of thetape player, through lead 130 and lead 131, to

the terminal 86b'of thedialing mechanism 86'. Since terminals 86a'and 86b of the dialing mechanism are on anormally closed switch, when the coil of relay 5' is energized and the-circuits completed as described, there is a closed circuitbetween line 128 of the telephone line and line- 129 of the telephone line, while the'circuit of line 128 of the telephone line is broken to all'other' instruments. in the building. However, if a connection was in. existence between another telephone instrumentlished. connection with an. outside. subscriber, the arm.

89' on the. dial plate 82 is: pre-set. to; a, position so that the. roller 90' on the. arm 89, whenthe syst'em'is set in' operation and the. dial plate. 82 begins to rotate, is in.

contact with the,leat"9'3 onswitch 94" opening the contacts and. breaking, the. circuit of line 1280fthe telephone line andTtermina-l 86a of the dialing mechanism.

86 When the dial plate 82' has. rotated-sufiiciently for the arm 89 to clear the. leaf 93 on switch94, the contacts close and the circuit is reestablished between line128.v of the telephone line and the contact8'6iz of the dialingv mechanism. The speed of the dialing: plate 82 is such that the contacts on switch 94 are'held open bythe roller 90 during contact with the leaf93 for a period of time which is sufficient-for any previous connection through the central oflice ofthe=telcphone company to please hang up-this is 1234 Central Avenue.

be broken, and to assure that suflicient. time will elapse after the contacts are closed. on switch. 94 to permit closing of the circuit at the central telephone exchange before the first peg- STb'egins turning the gear of the dialing mechanism 86.-

With circuits completed as described, the dial plate 82 continues to rotate until it has. completed dialing the desired'number anduntil' the roller 90. on arm.39'con contacts of delay. relay 127 are open, the dial motor 80 stops. complete the cycle described is. suflicient for the preamp 120"of the tape player to have warmed up and to be amplifyingthe signal which is being fed to the input. of the pre amp frorn'the burglar alarm tape head 104-' which is in circuit with the pre amp through the normally closed contacts 6a and 6b of relay 6.- When the telephone connection is completed by the. lifting-of the in.-. strument of the telephone. number which has been dialed, the message recorded on one half of the. width of the tape 106- of the tape player is transmitted to the person lifting the instrument.

To provide for the possibility. that the telephone line used is a party line andis in useby another partyon the line when the. alarm system is setin operation,- in which case aconnection through the centralofiice of the telephone company could not be established until the connection between the other party through thetelephone exchange is broken, the message could read as follows:

Emergency-this isan automatic burglar alarm Emergencythis is an auto.

This message will continue to be transmitted until the heater elementcloses the contacts in the delay relay 127 and the cycle of dialing, already described, begins. When the other party on the line hangs up, the connection with the number dialed by the mechanism 86 will be completed.

The number of repetitions of the message is controlled by the heating. period of the delay relay 127 andin this version of the invention has been set to. provide at least three repetitions between dialing cycles. When the contacts on the delay relay 127"close, current from the contacts 3c and 3d of relay 3 again reach the dial motor 80 which begins to rotate the dial plate 82 and the roller 90 on the arm 89on the dial-plate clears the leaf 91' on swicth 92, re-closing the contacts 92a and- 92b and the current now reaches the dial motor directly through switch 92 and the circuit to the. heater element of the delay relay 1-27 isbroken. Beforere-dialing begins, the roller 90 on the'arm89on the dial plate 82- again contacts leaf 93 on switch- 9.4, which opens the circuit of the telephone line 128'to re-establish a clearline to. the central exchange, toprovide against the possibility previously mentioned of apre-established connection of..

The time required'for the dial plate 82 toanother party on same line or of -an already established a connection at the number being dialed.

The cycle described of dialing, breaking the circuit to the dial motor, repeating the message several times, breaking the telephone connection, re-establishing the connection, and re-dialing will continue until action of the ratchet gear 110 opens the circuit of the 110 volt input current through the switch 117, or until the momentary switch 107has been pressed, disconnecting the 110 volt input current.

In the event that an excessive temperature rise occurs in the building protected by this system, the contact 64 on the bi-metal strip 63 closes with contact 65 in one of the fire alarm transmitters 59, energizing the solenoid 62, causing the tuning rod 66 to vibrate as already described and transmit a super-sonic signal which is received by one of the microphones 72 and fed to the amplifying and discriminating circuit, causing current to flow through the control tube 7 4 to the coil of relay 2, closing the contacts 2a and 2b and feeding the input current from the power supply line to the coil of relay 4. When the coil of relay 4 is energized, contacts 4a and 4]) close and permit input current to flow through lead 132 to the coil of relay 4 so that it remains energized after contacts 2a and 2b open on relay 2. When the coil of relay 4- is energized, it also closes contacts 4c and 4d which sends input current through lead 133 to the coil of relay 3, thus energizing and activating all of the circuits previously described under the burglar alarm sequence of this invention. With the exception that when coil on relay 4 is energized, contacts 4a and 4b are closed and furnish input current to the coil on relay 6, opening the circuit of the burglar alarm tape head 104- which was connected between contacts 6a and 6b of relay 6, and a circuit is established with the fire alarm tape head 105 through contacts 6a and 6c of relay 6. The recorded message on the other half of the width of the magnetic tape is now fed to the fire alarm tape head 105, which is now in circuit with the pre amp 120 of the tape player, and is transmitted over the telephone lines to the person lifting the telephone instrument at the number which has been dialed. As a precaution against the possibilities mentioned in the burglar alarm sequence of this invention, the message could read as follows:

Emergency-this is an automatic fire alarm-please hang upthis is 1234 Central Avenue. Emergencythis is an auto The cycle of the dialing, breaking the circuit to the dial motor, repeating the message several times, breaking the telephone connection, re-establishing the connection, and re-dialing, will continue, as described in the burglar alarm sequence, until action of the ratchet gear 110 opens the circuit to the 110 volt input current, or until the momentary switch 107 has been pressed, disconnecting the 110 volt input current.

It will be clear that some of the mechanical arrangements described may be replaced by others Without in any way affecting the operation or the result. However, the inclusion of the specific dialing mechanism, which is manufactured for the telephone companies, to provide the pulsing of the telephone circuit, rather than any other switch arrangement, is done advisedly in this embodiment of the invention to offset objection of the telephone company to the attachment to the telephone line of any device other than that designed to their specifications which is to be involved in the operation of their switchboard relays. Morever, it is clear that although this embodiment of the invention illustrates an arrangement using ultra-sonic sound waves for transmission of a signal, the use of audible sound waves, where they would not be objectionable or might even be desirable, does not depart from the general object and intention of this invention.

Having thus described our invention, what we claim as new, and desire to secure by United States Letters Patent is:

1. An alarm system comprising pressure sensitive cir cuit closing emergency detector means which when activated generate sound waves of a specific frequency, means to receive sound wave energy and transmit electrical impulses of the same frequency, means of a frequency selective nature to utilize the electrical energy provided by the said sound Wave receivingmeans only from sound waves of the specific frequency of those generated by the said emergency detector means to effect the energization of a relay, means operative upon the energization of the said sound wave activated relay to hold the alarm system in an operative position and provide a prescribed sequence of cycles of operation, means to provide connection to the telephone lines during the operative period of the alarm system of a dialing mechanism to call a pre-determined telephone station, means to provide during the operative period of the alarm system the transmission over the telephone lines of a recorded spoken language message, and means to terminate the operative period of the alarm system upon completion of the prescribed sequence of cycles of operation.

2. An alarm system as claimed in claim 1 wherein in addition to the emergency detector means of the pressure sensitive type there are also heat sensitive circuit closing detector means which when activated generate sound waves of the same frequency as those generated by the said pressure sensitive emergency detector means.

3. An alarm system comprising pressure sensitive circuit closing detector means which when activated generate sound waves of a specific frequency, heat sensitive circuit closing detector means which when activated generate sound waves of a different frequency from those generated by the said pressure sensitive detector means, means to receive sound wave energy and transmit electrical impulses of the same frequency, means of a frequency selective nature to utilize the electrical energy provided by the said sound wave receiving means only from sound waves of the specific frequencies of those generated either by the said pressure sensitive detector means or the said heat sensitive detector means to effect the energization of a first relay if the frequency of the sound waves is that of the sound waves generated by the pressure sensitive detector means or the energization of a second relay if the frequency of the sound waves is that of the sound waves generated by the said heat sensitive detector means, means operative upon the energization of either of the said sound Wave activated relays to hold the alarm system in an operative position and provide a prescribed sequence of cycles of operation, means to provide connection to the telephone lines during the operative period of the alarm system of a dialing mechanism to call a pre-determined telephone station, means to provide during the operative period of the alarm system in response to activation of the said first sound wave activated relay the transmission over the telephone lines of a first recorded spoken language message which describes the particular emergency which exists, and in response to activation of the said second sound wave activated relay the transmission over the telephone lines of a second recorded spoken language message which describes the particular emergency which exists which would be different from the first message, and means to terminate the operative period of the alarm system upon completion of the prescribed sequence of cycles of operation.

4. An alarm system according to claim 1 in which the pressure sensitive circuit closing emergency detector means are constructed by mounting a metal frame, covered by insect screening, over a metal window casing in a resilient manner and electrically insulated from the said metal window casing and the plurality of mounting members which exert pressure against the said metal frame through a plurality of grommets of rubber or some resilient electrically insulating material, such pressure against said metal frame through said grommets being 2 erable including ,a ratchet gear which is .rotated tone tooth during each dialingtcycle until an ,elongatedtooth of saidlratchet geancontacts a trip switch andcutstofi thetcurrent.

References Cited'in the file of thispatent UNITED STATES PATENTS 2;s45,472 Goldsmith Mar. 28, 1944 2,'498K,613 Talbot Feb. 21, 1950 2,780,671

Thery Feb. 5, 1951

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