US2353452A - Burglar alarm control box - Google Patents

Description

July 11, 1944. Q w H I I 2,353,452

BURGLAR ALARM CONTROL BOX Filed April 15, 1943 2 Sheets-Sheet l Z WPER CONDU/T PROTECTIVE DEV/(E5 W400. PANEL Patented July 11, 1944 UNITED STAT-ES PATENT OFFICE 8 Claims.

The present invention relates to a burglar alarm system and more specifically to certain imrovements in the equipment therein.

One of the main objects of the present invention relates to the incorporation of a visual means into an alarm control box that will at all times indicate whether or not such protective system is on or oil or analogously whether the same is in operation or not. Furthermore, such visual means is connected in series with and comprises one of the electrical devices of the system. The indicator is in series with all of the protective devices remotely controlled by the alarm control box, and said permanent indicating means is associated with such box.

Another object-of the present invention relates to the novel switching arrangement in combination with the control box and said visual means thereof. This combination also includes a control relay connected to open or close the bell circuit as the case may be under operating conditions of the entire system and depending upon whether or not the system is active or inactive.

The visual means is tamper-proof and is secured to an inner panel in the box with securing means hidden and protected by the control box cover. Various instruments or other devices can be used to provide visual indicators, but in the present case a milliammeter is utilized for that purpose.

The present alarm control box of the present invention also utilizes and incorporates a voltmeter of the push button type which is optionally connectable at will for expediting and locating trouble. Th voltmeter is mounted on the inner panel of the box and is covered by the box door, therefore only being accessible to someone having a key for said box. The meter is connected across the line of the protective circuit and whenever trouble should occur in the alarm system, the voltmeter will show whether such trouble is in the line and the protective system or in the control box itself.

Another feature of the control box resides in the use of a cam of insulating material forming a part of the key operated control switch for actuating the switch contacts when opening the alarm system circuit. In this connection it should be noted that the switch points are so arranged as to automatically fall into their normal operative alarm circuit relationship when the lock cam is turned to on position.

The same switch and cam lock arrangement cooperate to test the bell circuit and to set the alarm whenever the lock is turned by key, thereby rotating said cam for setting the system into operation. Furthermore, the control box cover is provided with suitable apertures for exposing the aforementioned visual means, and also, to provide access to the lock for the control switch without opening the door. The door has a companion lock thereon set to be matched with said control switch lock for the reception of the same key.

Other objects and advantages relating to the present burglar alarm system shall hereinafter appear in the following detailed description thereof having reference to the accompanying drawings.

In the drawings:

Fig. 1 is a general front view of the burglar alarm control box of the present construction embodying the various features and improvements relating to the present invention;

Fig. 2 is a cross-sectional view taken substantially along the line 2- 2 in Fig, 1, illustrating the upper portion of the alarm box in detail;

Fig. 3 is a general diagrammatic lay-out of a burglar alarm system embodying the control box of the present invention;

Fig. 4 is a rear view of the panel that mounts the instruments of the control box and the terminal block, the circuits and certain devices therein being diagrammatically illustrated in the present View;

Fig. 5 is a view of the relay of Fig. 4 but illustrating the same de-energized and in the bell ringin Position;

Fig. 6 illustrates the control switchand the lock of the alarm system when the same are in off position in contrast to the same being shown in on position in Fig. 4;

Fig. 7 diagrammatically illustrates another form of bell box from that shown in Fig. 3, as used in connection with the control box of the present invention; and

Fig. 8 is a detail sectional View of a pry-eff tamper connected with the control box and as viewed substantially along the line '8-8 in Fig. 1.

The control 'box as best illustrated in Figs. 1, 2 and 4 comprises a box -I having a cover 2 suitably hinged as at 3 to one side of the box I, with a convenient steel latch lock of a pick proof type as illustrated at 4 providing the means for looking the box in the normal fashion. A panel '5 is suitably secured by means of screws 8 to ears I provided on the box for that purpose; while a battery 8 is housed in the lower portion of the control box. The latch 9 of the box look when turned to open position is made to pass through an opening It provided in the panel when opening and closing the cover 2, and the lock ear II is of a reinforced type adapted for receiving the latch 9 to the rear thereof and behind panel 5 when the lock t is turned into locked position.

Referring now more particularly to Fig. 4, the panel 5 is provided with an ammeter I2, voltmeter I3, relay I4 having an L shaped pivotally supported armature I5 for controlling the bell circuit switch I5, and a main or master switch I! which is controlled by a pick proof lock I8 which in this case is identical with the lock 4 of the cover of the control box. Lock I8 however, does not have a steel latch a lock 4 but carries a cam member made of suitable insulating material such as Bakelite or phenoli'te for the purpose hereinafter explained. All of the foregoing instruments and switches are suitably mounted and carried upon the panel 5 together with a terminal block I9 which is insulated from the panel and which has a plurality of binding posts adapted for and conveniently arranged to receive the system wires.

Referring now to Fig. 2, it is to be noted that the panel 5 is so mounted and carried within the control box I as to have the ammeter I2 positioned with the face thereof visible through the opening in cover '2. Another opening 2! is also provided in the cover to permit access to the master or main control switch lock of the alarm system generally indicated at I3. In this manner it is possible to turn the system on and off without opening or closing the alarm box door, and furthermore, the ammeter I2 which in this case is a milliammeter for measuring the flow of current in the protective system, as viewed through the cover or door is a visible means for showing whether or not the alarm system is on or off. 1

The ammeter I2 is supported by suitable screws such as 22 upon the panel 5 and the heads of such screws are completely hidden and protected from tampering by means of the cover 2 which hides the same as best illustrated in Figs. 1 and 2. To further avoid tampering with the instruments in the control box, under conditions where entry may have been gained through the ammeter or its opening, a baflie member 23 is mounted upon the panel 5 to shield the rela -and the switches I6 and I? and, therefore, to guard against manual tampering with such devices. The baflle 23 is also used, as shown in Figs. 2 and 4, as an intermediate means for supporting relay M with its switch It and switch I7. Referring now to Fig. 3, the control box I is shown as connected with a plurality of protective devices that are diagrammatically illustrated and which represent some of the better known and more common safeguarding installations; all such devices and the control box being connected with the bell box diagrammaticall illustrated at 24. In Fig. 3, therefore, we find the leads or wires 25 and 26 connected in series with the protective devices and connected with the battery 21 which furnishes the current source for the protective portion of the circuit. Obviously, the leads 25 and 26 could be connected directly with the bell box 24, but in order to prevent the use of a separate conduit extending between the protective devices and the bell box, such leads are connected through suitable terminals on the terminal block IQ of the control box and then extend tothe-bell box 24 along with the other wires between said boxes.

The wire 25 is therefore connected to the bell Q the following manner.

box as shown in Fig. 3 and passes through several switches such as illustrated in Fig. 8, one Of which is known as a Pry-01f tamper diagrammatically illustrated at 28 and one or more tamper protective means 29 for the bell box door, and wire 25 is then grounded to the inner wall 30 of the bell box which is insulated from the outer wall 3| thereof. The wire 26 is also connected to the bell box 24 as shown in Fig. 3 and is grounded to the outer wall 3! thereof. The current passing through the wire 25 and the inner box wall 3!] of the bell box 24 is then conducted back to the control box I through the wire 32 which passes through the ammeter I2 and then on through the control box tamper switch 33 and pry-off tamper switch 34 and on to one side of the coil of the relay Id. The circuit is then completed by means of the connection 35 through the relay switch I6 when in the position shown in Fig. 4, and then along connection 36 to the master switch Il. When switch I! is in on position the current from 36 passes through the switch, and along conductor 37 to the terminal block of the control box and then passes back to the bell box 26 to be grounded to the outer wall or casing of the box. Obviously, the current then flows back through wire 25 and back through the protective devices to the negative side of the battery 21.

The modified form of bell box 33 illustrated in Fig. 7 may be similarly connected with the control box in the same manner as illustrated in Fig. 3 with the connections from the terminal block I9 being substantially as shown in Fig. 3. This modified form of bell box merel has been added by Way of example to illustrate that the control box I may be used in connection with either type of bell box with equal efficiency and convenience and that the function of such control box is the same in either installation. Other forms of bell boxes or alarm equipment may also be connected with the control box.

By way of illustration, the pry-off tempers and the tampers per se referred to in Fig. 3 are all substantially of the type illustrated in Fig. 8 wherein the same comprises a switch 39 mounted upon a bracket 4t secured to the box i, with a spring pressed switch operating member 42 held in closed or operative current position by abutting engagement with the wall or other means upon which the control box I is mounted. This same general arrangement applies to the tampers which are used in contact with the doors or covers of the various units such as the control box or the bell boxes illustrated. Such electrical alarm system controls are conventional and may be of any known type.

Referring now again to Fig. 4, it is to be noted that the master switch I? which controls the alarm circuit is provided with three spring contacts 45, 46 and 47 respectively, while the relay switch I6 is also provided with three spring contacts 48, 49 and 50 respectively. The bell circuit is completed through the switches I5 and S7 in Current from the bell battery 8 flows through the wire 52 to the switch I1, then passes through the contacts 46 and 45, and along the wire 36 to the center contact 49 of the relay switch I6. From here the current passes back through contact 48, and by reason of the fact that the spring contact 48, as in Fig. 4 is connected with-the open and free contact spring 41 of the switch II, no current will flow at this time through to the bell circuit. How-.

ever, should the coil of relay I4 be deenergized active position illustrated.

and the armature I tripped in the manner illustrated in Fig. 5, the current from the center spring contact 49 of switch I6 will then pass through the points of the contacts and through spring contact 5!], through the connections 53 and 54 and on to the bell 55 shown in Fig. 3. The

circuit is completed through the bell 55 back through wire 55 to the terminal block l9 and from there on through the connection 51 back to the negative side of the battery 8.

From the foregoing explanation, and by comparing Figs. 4 and 5, it will be seen that as long as the coil of relay I4 is energized the armature f5 will be drawn up and the alarm bell circuit will "be open. Whenever the coil of the relay becomes die-energized through an interruption in the protective circuit armature I5 will drop away from thebottom pole of the relay to permit closing of the points of the spring contacts 49 and 50 respectively, thereby completing the bell circuit and causing the alarm bell to ring. All of the switching units will function in the manner stated so long as the control switch I! is in the particular position illustrated in Fig. 4 wherein the insulated cam 89 of the lock I8 is in the open or in- Whenever the key controlled lock I8 is rotated with its cam 60 into the position illustrated in Fig. 6, the entire system will be shut off or rendered inactive in view of the fact that both the protective circuit and the bell circuit depend upon the contact points of the spring contacts and 46 of switch H for a continuous flow of operating current. As shown in Fig. 6, the cam 60 of the key lock I8 when rotated will cause contact 47 to abut an insulating peg BI whereby the contact points of the springs 45 and 45 are moved into separated positions rendering the system inactive.

Another feature of the present invention resides in the use of the particular control switch illustrated wherein the same is so arranged as to function as a means for testing the bell circuit and also for restoring the relay armature to the position illustrated in Fig. 4, whenever the key controlled lock I8 is rotated from the position shown in Fig. '6 to the open or circuit on position in Fig. 4. As the cam 60 rotates in the direction of the arrow in Fig. 6, the points of the contacts 45 and 46 will first engage under the action of the spring contact 45, completing the circuit to the bell by means of the closed circuit position of the relay switch I6 namely in the position illustrated in Fig. 5. This testing position may be maintained for a few seconds, and then the switch may be further rotated in the direction of the arrow in Fig. 6 whereupon the wiping contacts 63 and 64 are momentarily engaged. These contacts 63 and 64 are connected with the spring contacts 45 and 41 respectively, and act to momentarily complete the circuit from the protective system to energize the coil of the relay I4 for drawing up the armature I5 which places the relay switch into the position illustrated in Fig. 4 whereupon the system will then again be restored to its normal active position. When the wiping contacts 63 and 64 are momentarily engaged the current flow of the protective system will then be through wire 32, through the coil of the relay I4, through wire 35, into the connecting lead 65 which joins with the spring contact 41, and from the latter it will pass through the contact ends 64 and G3 and then through the spring contact points of the spring contacts 45 and 4'6 and back through wire 31 following the negative side of the protective system to battery 21. Once, that the armature I5 is restored as shown in Fig. 4, the additional movement of the member 60 of the lock I8 in the direction of the arrow in Fig. 6 will merely allow theswitch ll to resume the normal on position illustrated in Fig. 4. It should also be noted that the control switch I! has been so arranged and devised that the controlling contacts thereof will always automatically fall into their normal active on positions as shown in Fig. 4, entirely independent of the control lock position.

The voltmeter I3 has been incorporated into the system as a means for expediting the location of trouble in the event that such shall occur in the alarm system. The voltmeter however is not exposed through any openings in the cover of the box I and is of the push button type that is normally not connected in series with the circuit of the protective system. However, anyone who is given access to the box such as a repair man or other inspector can push the button on the voltmeter I3 which will indicate whether or not a maximum amount of current is flowing through the protective circuit. If the voltmeter indicates the voltage required in the protective circuit then the repair man knows that the trouble does not lie in the outside protective portion of the circuit but that the trouble exists within the control box mechanisms. As best shown in Fig. 4, the voltmeter is connected as at 68 and 69 to the positive side 32 of the circuit and the negative side 31 thereof respectively.

Therefore, with the above description of the arrangement of the various operating mechanisms of the control box it is seen that a very efficient and compact unit is hereby made available which has a number of features that are deemed to represent an advance in the art over devices of similar types. Also the box of the present construction will provide a means whereby a visual indicator is present to act as a means to clearly show whether or not the alarm system is active or inactive. The same box will also provide a means as explained for allowing the turning off or turning on of the system without opening the cover or door of the control box.

Furthermore, the alarm control box incorporates a switch of novel construction as illustrated in the drawings and described, wherein it is possible to test the bell circuit and the working of the alarm system and also to have a means for restoring the coil of the relay to its normal active alarm-giving position whenever such switch is being turned on.

It is obvious that various immaterial modifications may be made in the general arrangement and setup of the present preferred illustration of control box and the instruments therefor Without departing from the general concept of the original invention. However, such changes and modifications shall be governed by the breadth and scope of the subject matter of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a control box for an alarm system, the combination of a bell circuit and a protective circuit, a relay in said protective circuit having switch contacts for controlling said bell circuit and the protective circuit, a master switch for said system in series with the bell circuit and the portective circuit, and an indicating device in said protective circuit responsive to said master switch and relay to provide visual means to show whether or not said system is active.

2. In a control box for a burglar alarm system,

the combination of a bell circuit and a protective circuit, a relay in said protective circuit having switch contacts'for controlling said bell circuit and the protective circuit, a key operated switch in series with said bell circuit and said protective circuit operating to render the circuits active or inactive, and indicating means in series with one of said circuits and responsive to said switch means and relay to show whether or not Said system is active or inactive.

3. In a control box for a burglar alarm system, the combination of a bell circuit leading to a bell box, a protective circuit leading to one or more protective devices, a bell circuit switch, a. relay in said protective circuit and coacting with said bell circuit switch to control the bell circuit, a master switch in said bell circuit and said protective circuit to render said system active or inactive, and a milliammeter in series with said master switch and said protective circuit to provide visual means to indicate whether or not said burglar alarm system is operatively active or not.

4. In a control box for an alarm system, the combination of a bellcircuit and a protective circuit, relay means in said protective circuit for controlling said bell circuit and adapted to close said bell circuit whenever said protective circuit is opened, a master switch in said bell circuit and said protective circuit for rendering the latter circuit active or inactive, and an indicator in said protective circuit and responsive to the action of said switch to provide visual means to show whether said alarm system is on or off, said master switch including switch contacts for restoring said relay means to operative position whenever said master switch is turned from oil to on position.

5. In an alarm system. control box having a hinged cover, the combination of a panel within and secured to said box and disposed adjacent the cover side thereof, a master switch mounted on said panel and operating to render the alarm circuit of the system active or inactive, and an ammeter secured to said panel and in series with the alarm system circuit to show whether or not said system is active or inactive, said cover having two openings therein, one to permit a view of said ammeter and one to provide access to said master switch to turn the same on or off.

6. In an alarm system control box having a hinged cover, the combination of a panel within and secured to said box and disposed adjacent the cover side thereof, a master switch mounted on the inner side of said panel for turning said system on or off, a key operated switch actuating lock mounted on said panel with the key portion thereof adjacent said box cover, and including an insulated cam on the inner side of the panel to coact with said master switch to operate the same, said cover having an opening therein to expose said switch operating lock for turning the alarm circuit on or off without releasing the cover from said control box.

'7. In an alarm system control box, the combination of a plurality of instruments in said control box, a plurality of protective devices outside of said control box, a protective circuit for said protective devices, an alarm circuit connected with said box instruments, and a push button voltmeter in said box and connected across the protective circuit intermediate the devices and instruments to indicate in case of trouble whether the protective circuit or box instruments are at fault.

8. In a control box for an alarm system, the combination of a bell circuit and a protective circuit, a relay having switch contacts in said protective circuit and in said bell circuit, said relay having also an armature for opening and closing the bell circuit and the protective circuit, and a master switch having switch contacts in said bell circuit and said protective circuit for turning said entire system on or ofi, said master switch having auxiliary switch means connected therewith for automatically testing the bell circuit while turning said system on by means of said master switch and said master switch having a contact for momentarily closing the protective circuit, whereby to energize the relay and restore the armature to its attracted position.

ARTHUR W. FRUH.

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