US2783462A - Electrical protective burglar alarm system - Google Patents

Description

Feb. 26, 1957 L.. H. CHASE `r:r AL 2,783,462

ELECTRICAL PROTECTIVE BURGLAR ALAmsYsTEM Filed Jan. 27, 1954 2 Sheets-Sheet 1 F 1. PREM|sEs A PRI-:MISES B I 7 f1* I f." ,1

CENTRA L PREMISES C OFFICE PREMISES E FREMISES D LeRoy C. SpemarcL BY @MAQ A ORNEY Suk) Feb. 26, 1957 H. CHASE Erm. v 2,733,452

ELECTRICAL .PROTECTIVE BURGLAR ALARM SYSTEM Filed Jan. 27, 1954 2 Sheets-Sheet 2 I. INVENTORS |l|||'l' Leland H. Chase LeRoq C. Spenard United States Patent ELECTRICAL PROTECTIVE BURGLAR ALARM SYSTEM Leland H. Chase and Le Roy C. spenard, Pon washing ton, N. Y., assguors to Holmes Electric Protective Company, New York, N. Y., a corporation of New York Application January 27, 1954, Serial No. 406,541

Claims. (Cl. 340-276) The present invention relates to an alarm system and more particularly to a system which transmits signals to a central oice upon the entrance of an intruder or occurrence of re, in addition to sounding a local alarm and still more particularly to such a system in which a going out code is sent to the central otice when the subscriber leaves the premises.

In the prior -art systems of this type the subscriber sets up the system from the inside of the premises before leaving. A front door Contact or protective switch, which is in the alarm circuit for the premises, is shunted by a key-controlled switch on the outside of the premises.V

Thus the subscriber may open the front door to leave without disrupting the system. Once outside the keycontrolled switch is opened thereby putting the front door contact or protective switch back into the circuit. At the same time that the key-controlled switch is opened, a going-out code signal is sent to the central oce thereby indicating that the subscriber has left. One diiculty with this arrangement is that quite often, statistics show about of the time, the subscriber forgets to operate the key-controlled switch. This oversight will be detected in time in the central olice because of the absence of the i However, it is still necessary for g are ditierent from any other system on that particular central oice circuit. l f

Still another object of the present invention is to provide a burglar alarm system for use in a series connected central oili'ce circuit in which confusion arising from the garbling of signals resulting from two subscribers closing and leaving their respective premises at thesame time may be reduced greatly.

A still further object of the present invention is, to provide an improved protective system wherein when'the premises are about to be vacated, the subscriber can readily determine whether the local circuit is vin fac; in operating condition and wherein the subscriber cannot transmit the call-to-close signal until such operating condition is achieved.

Another object of the present invention is to provide lan improved protective system wherein in addition to automatic occurrence of a signal upon reentry of the premises, as in the Imorning, a manually yactuated signal is given by the subscriber after he reenters the premises. An advantage of this arrangement is that the chances of garbling two or more signalsbeing sent to the central oce are reduced, thereby facilitating identication of Furthermore the second manually actuated signal assures the central'oice personnel the signalling premises.

that the entrance is authorized and that thereis not a disturbance taking place which just happens to coincide Fig. 3 is a straight line diagram of several motor drivenv cams showing their lrelation to each other.

Referring to Figs. 1 and 2, signals from the local system,

as for example premi-ses A, are sentfto the central ofce over lines 10 and 12. The lines 10 and 12 are connected in a series circuit which includes the central office and from the inside and then operate the key-controlled switch on the outside.

Another di'culty with prior art arrangements is that it is impractical to have more than one final exit door by which the protective system is set up.

'It is, therefore, an object of the present invention to l provide a burglar alarm system in which the going-out signal is given automatically when the subscriber closes the exit door of the premises.

Another object of the present invention is to provide l a burglar alarm system in which the going-out signal is given automatically when the subscriber closes any exit door of the premises.

a burglar alarm system in which :a goingfoutsigna1 l which is peculiar to the particular premises is given when the subscriber closes.

Still another object of the present invention is to provide a burglar al-arm system in which the system is set-up on the inside of the premises, at which time, a lirst, callto-close signal is emitted and in which a second, going'f Another object of the present 4invention is to provide a burglar alarm system which is to be connected ina central oiiice circuit in series with several other systems` and in which each such system produces signals which A further object of the present invention is to `provide 5 the systems of the other subscribers connected on this particular line, as shown, including -the premises A, B, C, D and E; While but rive subscribers are shown, it will be understood that the number may be varied. The line 12 is connected to the cont-act lever 14 while the line 10 is connected to one of the contacts 1'6 of the pin lock .y switch 18. When thelkey 20 ofthe pin lock switch is withdrawn, which is the case when the 4system is set-up, the contact 16 fis connected to contact 22 which in turn y is connected over line 24 to the contact lever 2,6. The contact levers 14 and 26 are arranged to be bridged by the teeth on the motor driven code wheel 30. It can be seen` from this that the only connection'between thel local system `and the central office circuit, once the system is set up,Y

is through the actionof the code wheel 310;V When a signal is to be sent to the central otlice yfor any reason, the motor 32, which drives the code wheel-through gears 34 and 35,

isV energized to cause the code wheel to rotate, the gearratio being 6 to l. When this occurs the circuit through the contact levers is successivelymade and broken duet-othe action of the various metallic and insulating teeth iot the code wheel thereby alternately making and breaking the central-ofce circuit. Thisoccurrence is detected in the central office by appropriate detection and recording devices. Since in the system under consideration several,

usually 15, subscribers are connected in. series in a single accomplish this the code wheel is originally cut with nine teeth which will produce nine breaks in the central ofiice circuit during each revolution of the code wheel.

Patented Feb. as, 1951 argano Y breaking pff appropriate teeth each of the fteen subscribers on a single circuit can be assigned a different code signal thereby eliminating any diiculty in distinguishing-signals `from the various subscribers. The c-odevwheel is'described and claimed in'copending applicationv Ser. No. 357,016, tiled May 25, i953,

The local protection circuit is connected to receive power `fromthe battery 36 which has its positive terminal grounded through the local plurnbing. V This circuit is a series circuit consisting ofthe resister 38, variable resister 40, meter 42, contacts 44 and 46 of the pin lock switch 18, line 48, various protection element-s such as door, ywindow and tamper switches and metal foils 50, line 52, vthe coil 54 of the lalarm relay 56, line 58, various 1other protection elements 60 and the ground return lead 62; This circuit is completely independent of the other local circuits but causes actuationof them through the operation of the alarm relay 56.

Also connected to the battery 36 is the line 64 which supplies energy to the `various other local circuits. The armatures `66 and 68 of the alarm relay 56 and the code unit relay 70, respectively, and the contact 72, over line 74, are all connected t-o the line 64. The line 74 is also connected to the contact 76 of the pin lock switch 18. When the pin lock switch key is removed contacts 76 and 78 are connected and the circuit is completed over line 80 to the armature 82 of the bell relay 84. When the bell relay 84 is -energized,armature 82 engages contact 86 and the circuit is grounded through the relay coil 88'.v

As previously pointed out the signal to thecentral otiice is produced by opening the connection between contacts 14 and -26 -as a result of rotation of the code wheel 30. The-motor 32 which drives the code wheel has one end of its amature grounded and the other end connected to theline 90. This line is electrically connected to the insulated cam followers 92, 94, 96, 98 and 100 of the cams 102, 104, 106, 108 and 110 respectively. The camsrare rotated -by the motor 32, cams 104, 106, 108 land 110 being in the motor control circuit and the cam 102 being in the circuit of the alarm bell 112. The alarm bell has one end connected to the battery 114 and the other end connected to the contact 116 of the bell relay 84. The contact 116 `is arranged to be engaged by the armature 118 of the 4bell relay. The cam `followers in the motor control circuit are arranged to be connected to the battery 36 through the action of the cams and various -relays and keys as will be described subsequently.

Assuming `now that the subscriber is vleaving the premisesand desires tovset-up the alarm system, the various doors, ywindows and other sensitive areas which are protected Ibyswitches etc. are lclosed and the pin-lock key 20 is removed 4from the pin lock switch. The removal of this key bridges the contacts 44 and 46 in the local alarm circuit causing the relay 56 to be energized. The current in the circuit is adjusted to -the correct value as indicated in the meter 42 by varying the resister 40. Such an ad justmentmay be necessary about once a month to compensate for battery deterioration. The resister 38 protects the meter fromserious overloading.

The removal of the key 20-also bridges the contacts 16 and 22 in the central oice circuit and contacts 76 and protective elements are properly set and are in good worka ing order. The goingfout signal indicates inthe central oce that the subscriber has opened and closedhis exit door for the purpose of leaving his premises,l at which timethe premises are oicially considered to'be under theprotection 'of the central office. Another reason for the two signalsis to greatly reduce the possibilityof the Vsign-als being lgarbled as a resultof another subscriber on theline penformingthe operations at the same time.k Toproducer the rst signal the call key 120 is pushed, provisions also being made through indicating circuits associated with this key for giving an indication of the condition of the local protection circuit. Assume for the moment that the local protection circuit is open for some reason or another. The relay 56 will be de-energized and its armature 66 will engage contact 122. `Current will then pass through line 64, armature 66, contact 122, Acontacts 124 and 126, these latter two contacts being bridged due to the fact that the call key 120 has beendepressed, line 128 and the red lamp 138. The red lamp -indicatesthat there is a fault in the local protection circuit.

Now assume that the fault has been corrected and the call key is again pushed. Current will flow from battery 36 over line 64, armature 66, contact 67, contacts 132 and 134 which are bridged by the cali key 120, line 136, contact 138 of the cam 106, cam follower 96, the cams being in the position shown in Fig. 2, line 90, camfollower 94contact 140, line 142, the green lamp 144 and coil 146 of the code unit relay 70. This will cause the green lamp to light, thereby indicating that the Vlocal protection circuit is in operating condition. At the same time the motor 32 starts to rotate, having received energy through contact 138 and cam follower 96, and starts the,

cams vtoward position #2 shown marked on the cams. As pointed` outabove, the coil 146,also receives current and picks up its armature 68.A Therefore, `even ifthe ca ll key is released the green lightl and the motor remainenergized through the armature 68 and contactv148, Bef fore the motor `cornes to rest at positoin #2 the following cam action takes `place: See Fig. 3. Shortly after `the mot-or starts and before cam 106` causes the cam follower 96m disengage` contact 138, the cam 104 causes the cam follower, 94 to engagefcontactf/Z. This causes the motor 32 to .be connected directly tothe battery over lines 64, 74 through contact 72, armature 94 and line 90. When cam .106 opens, its switch it opens the greenlamp 144 as `a Agenerator fora period long enough to prevent the, inertiafofA the armature of thernotor from carrying the.

camsequence pasttheposition #1.

As the'cams turn from position #1, the starting po si-.l

tion shown in Fig. 2, to position #2, the code wheel has revolved.` once,-sending in therst callfto-close signal. v

The callkey 120, codeunit relay. .70, red lampv Aand greenilamp144 haveperformed rtheir functions and do notenterin'toany ofthe subsequent operations of the msequences...

When the cams reach position #2,. see Fig. 3, all of the carnfollowers are in the same position as in position #l except camnfollowers 96 and 98. Cam follower 96 has disengaged contact 138 and. cam follower 98 has en. gaged contact 150 which is connected over line 15,2.to

thecontact 122 ofthe alarm relay 56. Referringto Fig.

3, 'camfollower 941s in a cut and is 15 away from operation. Carnfollower 98 is in a cut and is 10 away fromoperation. Cam follower 100 is 5 awayfrorn operation.

(Referenhinernade tothe. upper graph 106,in1iig43-) This arrangement is .awaiti ng the subscriber toopenthe front door which will, cause, the .alarmrelay S6 tobe de-. energized since thefront door switchf is in the alarrrrrelay.. circuit. The, .arnjia ture -66 is dropped vand engagesco'm,

facts-1.2.2,. thersbyf'enersizias the motor 1.32v ,thrpushsonr fachl and sata -tOllQu/sr 98.4 Whenv thiscurs the .-1 meterrotates and, turns-the camsthrough, an:.ar. =;ef;-1Q?j at which point the cam follower 98 disengages .contact 150 Y as 7.a resultof-fthe action of -thecana ,108.'` Asyet,Y no

code' signal hasbeen transmitted. During this4 10 rotationl to position 2n, however, the cam follower. 100` has engaged contact 154 of cam 110 and is connected over line 156 to the contact 67 of the alarm relay 56. At this point the entrance door is stiil open and the alarm relay is still deenergized. The door can be held open indefinitely as the second, going-out signal will not be sent until the door is closed.

When the subscriber closes the door the local protection circuit is again completed and the alarm relay is energized. The motor 32 is energized over line 90, through the cam follower 100, contact 154, line 156, contact 67, armature 66 and line 64. Cam follower 94 is again raised by rotation of cam 104 and the motor is connected to the battery through cam follower 94 and contact 72. The motor rotates to position #3, the second, going-out signal now having gone out to the central oice. The circuit is now ready to respond to any alarm condition. The cam follower 98 is resting in a notch on cam 108 and therefore is engaging contact 150. If for any reason the relay 56 is deenergized and the armature 66 is dropped, the motor will be energized. The cuton cam 108 is only long enough to keep current supplied to the motor until the cam follower 94 rises out of the depression at position #3 and takes over the job of keeping the motor going through the remainder of the cycle. As can be seen from Fig. 3, the cam follower. 94 of cam 104 will not reach another depression until position #l is again reached. The cams will rotate 240 degrees and therefore will send in a group of four separate signals. This group of four equally spaced signals, which is readily distinguishable from the two irregularly spaced call-to-close and going-out signals, is indicative of an entry into the building of an intruder or of a tire or other disaster which may produce a fault in the local protection circuit.

During the rotation from position #3 back to position #l the cam follower 92 has fallen into a depression on cam 102. This energizes the local alarm bell 112 as a result of the energization of bell relay 84. When cam follower 92 falls into the depression it engages contact 158 and connects the coil 88 of the bell relay 84 to the line 90. The relay picks up armature 118 and causes it to engage contact 116 thereby completing the circuit through the bell 112. Energization of the relay 84 also causes it to pick up armature 82 thereby completing the holding circuit for the relay. Therefore, the bell will continue to ring on the premises until someone from the central oice shuts it olf. The condenser 160 which is connected in the holding circuit, will hold the relay energized for short intervals should the holding contacts be momentarily opened due to blows struck upon the apparatus by the intruder.

Attention is called at this point to the normally open contacts 166 and 168 of the pin lock switch 18. The function of this portion of the switch is to shunt contacts 76 and 78 of switch 18 if anything other than the regular pin key is inserted into the lock switch. Thus, should an intruder attempt to silence the bell by using a drill rod similar in diameter to the pin key 20, he will be unable to interrupt the holding circuit because contacts 166 and 168 will be bridged before contacts 76 and 78 are opened. In normal operation the contacts 166 and 168 remain open because of the annular groove in the pin key opposite the location of these contacts.

A momentary alarm condition in the protection circuit of approximately one-half second is sucient to cause enough rotation of the motor to operate the cam follower 94 of cam 104 which will then supply continuous power to the motor for the duration of the four signals representing an alarm code. Anything less than half a second will not send the alarm code but the effect of a series of short alarm conditions are cumulative and if enough occur during the protection period an alarm code will be sent to the central ofce. This short delay, which is provided by proper formation of the cam grooves,

presents no hazard to protection eliiciency but does'gi'v a considerable operating advantage by forestalling what would otherwise be an alarm visit caused by a minor circuit disturbance.

When the subscriber opens up .in the morning he has the same effect on the system as would an unauthorized visit. This alarm will be recognized as due to the subscriber since the premises will usually be opened about the same time each day. However, since it may bev necessary for the subscriber to visit the premises other than at the usual hour, additional means are provided yto allow the subscriber to signal the central office independently of the local protection circuit. For this pur pose the contacts 162 and 164 are added to the call key circuit. These contacts are connected in the central oflice circuit in parallel with, the contacts 16 and 22 of the pin lock switch. When the'pin lock key 20 is inserted, this usually taking place when the subscriber enters the premises, the contacts 16 and 22 are opened and the central office circuit can then be opened by pressing the call key 120. Thus, manual signals can be sent in to the central office. The contacts 16 and 22 are included in the pin lock switch 18 so as to prevent undesired opening of the central oice circuit when the subscriber calls in to close in the evening; the contacts 16 and 22 shunting contacts 162 and 164 at this time.

The system has been described thus far as one in which it is necessary for the subscriber to open and close the exit door in order to send in the necessary goingout signal. However, in some installations, the system may be applied to the protection of a vault, only in which casethe second going-out signal will not occur. Thus, means must be provided to allow the going-out signal to be sent as soon as the system is set up and the call key is pushed.

This' is accomplished by resetting the cam 110 to the position represented by the bottom dotted graph of Fig. 3 and the dotted cam 110' in Fig. 2. The operation of the circuit is the same up to the pushing of the call key and the rotation from position #l to position #2. However, in this embodiment the cam 110 has been rotated 10 so that its notch is now positioned 5 before the notch at the position #2 of cam 104. Therefore, before the motor is disconnected from the battery as a result of the operation of cam 104 the motor is connected through cam follower and contact 154 to the battery 36. The notch in cam is long enough to keep the battery connected to the motor during the period that cam follower 94 is in the notch at position #2. After the cam follower 94 rises out of that notch, cam follower 100 also rises and the motor continues to rotate until position #3 is reached at which time the motor stops and the system is set-up. Both signals have been sent to the central office and from here on operation of the system is the same as previously described.

As shown by the above, the system requires only one operation by the subscriber to set up the system and the need for performing a second operation after the premises are closed is eliminated. The going-out signal is readily distinguishable from the alarm signal and manual means are provided for signaling the central office when opening up in the morning. Also the system may easily be changed, by adjusting a single cam, from one which sends out the first call-to-close signal when the system is set-up to one in which both the call-to-close and goingout signals are given when the system is set-up on the inside.

As this invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, the present embodiment is therefore illustrative and not restrictive, since the scope of the inven tion is defined by the appended claims rather than by the description preceding them, and all changes that fall within the metes and bounds of the claims or that form 7 theinfunctionalaswell as conjoint-ly-cooperative equivalents,-are therefore intended to be embraced hy those claims.v

What is claimed is:

l. A burglar alarm system comprising a local protection circuit including a local protection circuit switch and a plurality of protection elements located at sensitive areas inthe enclosure to be protected which protection elements are closed when the enclosure is locked up, a source of energy, a circuit connected with a central office and having a switch, means for closing said local protection circuit switch and central oice circuit switch when the system is to be energized, a normally closed switch connected in the circuit to the central oiice and shunting said central oice circuit switch,` means for "opening said normally closed switchfor opening the circuit to the central otlice when said central oliice switch is open, code wheel means actuatable for opening and closing said circuit to the central oice, a motor for driving said code wheel means, means for testing Whether the local protection circuit is completed and for actuating said motor so as to drive said code wheel means through a first preselected angle of rotation to send in a signal to the central oice, means responsive to opening of a protection element for actuating said motor to drive the code wheel means through a second predetermined angle of rotation, means responsive to closing of said protection element for operating said motor to drive said code wheel means through a third preselected angle of rotation to send in another signal to the central ofce to indicate the system is set up to detect the unauthorized opening of any of said protection elements, a local alarm device, means energizing said local alarm device subsequently to the actuation of said motor to drive said code wheel means to send in an alarm to the central office.-

2. A Aburglar alarm system according 4to claim 1 wherein said means for testing whether the local protection circuit is complete comprises a relay in the local protection circuit, a manually actuatable,normally openA switch in series with one of the contacts of said relay,` an

armature against said one contact` when said local pro-v tection circuit is complete and said relay actuated, said armature being connectedwith saidsource of energy, anV indicating lamp connectedvwith said manually actuatable,.-

normally open switch;

3. A burglar, alarm' system according to` claim 2 additionally including another relay contact, said armature being, against the latter contact when said local protection circuit is incomplete .and said relay is de-actuated,. another indicating lamp, a normally open switch actu-k atable in lcommon with said manually actuatable, normally open switch in the circuit to the yfirst recited lamp connecting` said latter contact with said second recited lamp sonas to vcomplete the circuit to the latter lamp whenl the local protection circuit is incomplete.

4. kAr` burglar, alarm system according to claim l y, wherein said means for testing Whether thelocal protec-4 tion circuit is incomplete comprises a relay in the local protection` circuit deenergized lwhenthe local protection circuit is open-an armature and at least one contact for said relay, saidarmature being against one of said con-H tacts when said relay is deenergized, an indicating lamp, a normally open, manually actuatable switch connecting said lamp to. said oneicontact lso as to indicate that the the` motor through. cam-operated levers each of which` vhas a separate cam cooperative therewith, and wherein at least one of saidqcams can be rotated to an angularly displacedv position relativelto the others Iso as to `'vary the operation ofthe `system and omit the signal sent "in-- by the code wheel during rotation through its third predetermined angle.

References Cited. in the file of this ypatent U1 \IAlTl-Elp)p STATES PATENTS 2,346,171: Laford Apr. 11,1944 2,492,432 Lafordl Dec. 27, i949 2,538,968 Houghton .Tan` 23, 1951

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