US2491987A - Burglar alarm - Google Patents

Description

Dec. 20, 1949 M. s. LEP- COURT 2,491,937

BURGLAR ALARM Filed OCT.. 5, 1948 2 ShetS-Shet 1 Dec. 20, 1949 M s, LEFQQURT 2,491,987

BURGLAR ALARM Filed Oct. 5, 1 948 2 Sheets-Shea?l 2 WILT 24,

Z! ma 2/ o 75a INVENTOR.

zz/f/wgj.' lynn/if! atented Dec. 20, 1949 UNITED STATES PATENT OFFICE Claims.

This invention relates to burglar alarms and has for its object to lprovide a self-contained transportable unit, which may be readily connected with an electrical supply circuit and with a door, window, etc.

The improved device when in safe state, gives off a steady glow of light which may be readily seen so that the user may be assured that the circuit is in operative condition, and all contacts are secure. It also gives an intermittent light signal and `a sound alarm when danger exists, that is, when the window, door, or Venetian blind is being tampered 'with and contacts are broken. The underlying concept is the use of a two way bulb as a power consumer, either to constantly glow, or operate a buzzer with flickering of the light.

The invention consists of :a self-contained unit having a base, `and la two -way pilot bulb and buzzer, electrically connected, with la connection to the source `of supply and another to the door or window, the lamp giving a constant glow yof light under safety conditions and a sound and intermittent light in danger conditions. Prefer- :ably a transformer connected with the house circuit is used.

The invention will be more fully described hereinafter, embodiments thereof shown in the drawings, and the invention will be finally :pointed out in the claims.

In the :accompanying drawings:

Fig. 1 is a perspective view of my improved unit;

Fig. 2 is a side view of the same;

Fig. 3 is a view taken vfrom the line S--s of Fig. 2 in the direction of the arrows;

Fig. d is an end view;

Fig. 5 is a side view of a modified form; and

Fig. 6 is a wiring diagram.

Similar characters of reference indicate corresponding parts throughout the various views.

Referring te the drawings la base ID, has two upright supports II and I2, in which a. transformer I5 is held in elevated position to provide a space between it, and the base IIJ.

Disposed between the supports II and I2, and supported by the transformer cover I4, is a buzzer coil I, and clapper with points I3, and a lamp socket I1 with a lamp I'Ia. Connecting conductors and binding posts Iare provided, to provide the circuit diagrammatic-ally shown in Fig. 6. Here, the source of electrical supply is connected to conductors 2B and 22. One conductor 20 is connected with the transformer coil 2I, to which a conductor 22 is connected. The other transformer coil 23, has one conductor 24 connected with one member of a breakable control 25, and the other member 26 of the breakable control 25 is connected with a conductor 2l, which passes =a two way pilot lamp I'I'a, and then by a conductor 23 connects with the other end of the transformer coll 23. 'Ihus the owner can see by the steady light that everything is safe, and by the intermittent light that danger exists, in addition to the alarm sound. The transformer I5 has the usual iron core I5a.

Shunted across the conductor '24 and the lamp I'Ia are conductors 29 and 29a, both conduc tors 25 `and 29a being connected with the buzzer SI. Thus, when the improved device is in circuit, the current causes the lamp I'Ia to provide a steady glow, and the buzzer is quiet. If, however, the breakable control 25, is disconnected, the main circuit is broken and the shunt current activates the buzzer 3 I, and the constantly interrupted current causes the lamp lla to flicker. Instead of a buzzer, la bell or other noise producer may be used.

In Figs. 2 and 5 the supports II and I2 are fused to the transformer case, and suitable insul-ation is provided for other parts where necessary.

In the practical embodiments given las examples, one has the buzzer .and lamp socket attached to the transformer cover, and the other, has these parts substantially integral with the transformer cover. A Bakelite or the like enclosing hood 40 preferably translucent encloses all the parts.

In the practical embodiment, shown in Figs. 1 to 4, the transformer has two terminal connections 35 and 35a projecting out of its transformer case, and the base I0 has two terminal connections 36 and 36a. The bottom of the transformer I5 has the connectors 37 and 31a. A lamp base 38 is supported by the bottom of the transformer :by a spring clip 39, secured by a screw 39a to the bottom of the transformer I5.

A plug 4I for the supply wires 2l) and 22, is provided for convenient connection with a house circuit. A similar 'plug 42 m-ay be used in Fig. 5, to conveniently connect the selfcontained unit to the -breakable connection 25.

The terminal connections 36 and 35a are preferabiy exterior to the case to enable the conductors which lead to the breakable parts, as a window screen door, Venetian blind, etc. to be electrically united to the selfcontained unit.

In the embodiment in Fig. 5, the buzzer and lamp socket are made integrally a part of the bottom cap I4 by welding the parts of the buzzer and the support for the standard lamp socket directly to the bottom plate of the transformer. Preferably a joined pair of terminals in a casing 24a takes the place of the two terminals 36 and 36a of Fig. 1, which may be attachably engaged by a female connector 42 to embrace the two terminals in the casing 24a. Such an electrical connection is well known, as used in electrical household appliances, as bread toasters, irons, heaters, etc.

Suitable screws 45 fasten the uprights I l and l2 to the base l0, which may be bolted or screwed into the base. Some of these hold down the cover 4D.

It will be particularly noted that in Fig. 3, the current after it leaves the coils I6 passes to a vertical abutment i3d, which is intermittently vpressed by the spring lb, which conducts the current to its support l3c, which is connected with the conductor 24 at the post 31.

It is noted that the essential feature o f the invention is the circuit with the breakable mem.- ber, supplied by any .Source .of electricity whether a transformer connected by the house circuit, er, a battery, and a circuit for the buzzer across the main circuit, but connected with the third contact of a two way bulb, the bulb under normal condition, that is when the .Constant glow takes place acts as a consumer o f the power, and then when that circuit is broken, the current jlows through the bulb (the third Contact) and is consurned `in the buzzer during the action f the buzzer.

It is seen that a self-contained appliance has been provided, which may be readily connected with a source or electrical energy, and with detachable control member applied to a window, or a door, etc., of a house, a cellar, a garage, a barn, ete. by any unskilled persen, and es readily detached, and does not act as a fixture to the premises, but 4may be teken ,along when the owner of the unit moves from place to place. Its use adds an element of security te users of .the unit- When used it takes `se little space that it is not readily seenJ .but .the slow ,of liebt er its flickering is at all times visible.

.wish it to be .understood that I .de nel? desire te be limited to the .exact details ef eenstruetien shown and described, .for obvious modifications will occur to a person skilled in the art,

I claim:

1. ,In a burglar alarm, .self-eentairled ,unit including the combination of a base, `a transformer spaced .from and supported .by seid base. a .lame bolder supported by Said transformer and between the transfcrmer and `tbe bese .adapted t0 ,support a three way lamp bulb in said holder, a noise producing device supported by saidtrans fermer and between -the transformer and the base, electrical conductors connected with a source of supply and with said transformer, with said lamp and with said noise producer, and a member for breaking the closed circuit connected with said conductors and said member, said conductors being arranged to provide a closed circuit when said circuit member is closed with a constant glow of the lamp, and on the breaking of said circuit member, provide a flickering light @19d ns@ Fl'odlitonz 2. The structure of claim 1, in which the lamp ,support and noise producer are substantially integral with a bottom cap of the transformer.

3 The structure of claim 1, in which the main circuit includes the transformer coils, main coil of the lamp, and closed circuit member, and a shunt ,circuit includes the coil of the noise producer and the other coil of the lamp.

4i: The structure of claim 1, with a translucent hood enclosing all parts save the terminals for the circuit member, and connections with the source of supply, the unit being transportable to any door or' window or the like.

5. In a burglar alarm, the combination of elecf trical conductors having spaced terminals conneet-ed with a source of electrical Supply, a trans'- former having its primary connectedwith said conductors, and its secondary connected with a second pair of conductors, said second pair of conductors formingj a closed circuit, a member for breaking said closed circuit vforming a'iirst and a second part, a two way, three contact lamp having two oi its contacts connected in series with the first part of said circuit, between vsaid member and the secondary, a current interrupting noise producing device having one terminal connected with the'third contact of the two way lamp and its other terminal connected with the second part of said circuit between'sai'd member and the secondary, whereby, when said circuit is unbroken, said closed circuit energizes only the said two contacts of the llamp to a constant glow without visibly energizing the third'contact Aand operating the incise producer, `and when said circuit is broken, the said third contact of the lamp in circuit Ywith said noise producing device is energized Without .visibly energizing ,the seid twe contacts, and a flickering of the lamp and a noise producing takes place,

MURRAY vs- LEFQOURT- REFERENCES CITED) The following reierences are of record in the nie of this patent:

UNITED ySTATES PATENTS Number Name Date 1,305,190 Bobo TTv v May 27, 1919 2,259,696 Hulst V T Oct'. 21, 1941

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