US1808491A - Burglar alarm and lock therefor - Google Patents

Description

June 2, 1931.

-E. BELLMAN BURGLAR ALARM AND LOCK THEREFOR Fi-led NOV. 26, 1928 EDWARD BELLMAN, OF ROOIFOBD, ILLINOIS BURGIAR ALARM AND LOCK THEBEFOR V.Application led November 28, 1928. Serial No. 821,930..

This invention relates to a burglar alarm and lock therefor.

Objects of this invention are to provide a novel form of burglar alarm in which a lock I 5 is employed, controlled by a removable key for throwing into or out of operation, the entire alarm system,so that the owner of the house or building in which it is installed may readily throw into or out of o eration, the entire system, with no more e ort than is required to lock a door.

' Further objects are to provide a device which is so constructed that it will present no screws or other members which could 5 he removed, but instead, which presents a 'plate 'tree from any such fastening means and which is so made that if it is attempted to pry the plate loose 'from the rest of the apparatus in order to pick the lock., that this 9 operation itself will start the alarm; the alarni system being so constructedthat the alarm continuously sounds after it is once started. Entrance must be made to the inside at a designated placey to stop the alarm. g5 The lrey to the lock will turn the alarm on, but not ed, after the hell has started.

Further objects are to provide a device which is easy to construct and isvery easy to install, and which is so made that no 3@ thought is required on the part of the user other than merely inserting a key and operating the lock.

An embodiment of the invention is shown in the accompanying drawings, in which:

v Figure l is a rear View oil the loclrwith parts broken away and in section, such view showing a portion of the systeni..

Figure 2 is a longitudinal sectional view through the lock. 4G Figure 3 is a transverse sectional view on the line 3 3 of Figure l.

Referrin to the drawings, it will be seen that the loo comprises an outer metal plate l. This metal plate is provided with a plu- 45 rality of threaded pins 2, which are perinanently set in the plate on its inner side and secured in an permanent manner, as by soldering, wel ing or in act, i n any other way. These pins serve to position an insu- 50 lating sheet 3, which is positioned to the inner face of the plate l. This insulating sheet has positioned thereon a metal plate 4, which is provided with a centrally bulged portion, an with rounded ends, as indicated in vFigure l. The metal plate 4 is provided `5l-5 with apertures which are counter-sunk to receive the tapered heads of rearwardly projecting bolts 5, by means of which the lock may be secured in place. This metal plate is held in place by means of an insulating' plate 6, (see Figures l, 2 and 3). The insulatingplate is held in place by the threaded ring-nut 7 of the tumbler carryin portion or barrel 8 of the lock. 4rlhis loc may be of standard construction and may be provided with a hey-hole in the usual way, adapted to receive an operating key.

l' llie rotatable portion at the rear of the loclr carries a cam member 9 (see lili res l and 2), which is equipped with a heyehole into'which the lrey enters when inserted in the lock, so that when the lrey is operated, the cani'portion 9 operates and controls contacts, hereinafter to be described.

A relatively short spring contact l0 is secured 'by means of bolts ll to the insulating plate 6. A relatively longer sprin Contact l2 is also secured by means of bo ts 13 to the insulating plate. The longer4 contact member l2 is movable and normally engages the contact l0; however, when the lock is unlocked, the ca'in member 9 or the lock member moves the spring contact member l2 outwardly away from the spring contact ld, and the system is now rendered inoperative. @5 -When it is desired to throw the system into operation, the user merely inserts his key and operates the loclr as it he was lochng it. This rotates the cam member 9 in a clock@ wise direction, as viewed in Figure l, and @il allows the contact l2 to engage the contact 10. The contact l2 is connected to a' small metal clip le, which is in turn con? nected to the inner metal casing l5 oit the loclr. rlhis inner metal casing is also connected to a paiir of inwardly projecting metal lingers 16, or stationary Contact members 2 (see Figures l and 2), which overhan the metal plate d. l

T e bolts 2, or threaded pins, pass through the inner Han s of 'the rear casing 15 and flexible cable, having a pair of conductors Vsus 17 and 18 and having the metal sheath 19. This metal sheath may be merel a wrapped wire surrounding the insulated conductors 17 and 18. It is connected to the plate 4,

-so that the metal sheath itself forms one portion of a circuit, hereinafter to be described. One of ythe conductors, 18, is connected to the sprin contact'member or movable member 12 an thus to the clips orjcontact members 16 of the front plate. The other conductors, 17, of the ca le, is connected to the contact member 10. l

' It is obvious that a three-wire cable could be employed, but it is found cheaper to use the sheath of the armored cable as one of the conductors, thus cutting down the expense and also serving an additional purpose, which will hereinafter appear.'

The conductor 17 is connected by means of the wire 20 to a plurality of movable contact members,.as lndicated at 21 and` 22,v

of a lurality of alarm units. These contact mem ers are covered, the cover being remov-.

able only in formin a contact so that when the s stem is turne on the alarm must respon if covers are removed. The stationary contacts 23 and 24 for such 'units are connected b means of a conductor 25 to the metal sheat 19.

Further, the wire 25 is connected to one side of a battery 26 and also to one side of an `electrical bell or other alarm member 27.

The other side of thebattery 26 is connected through the coils of an electro-magnet 28 to p a wire 29 leading to the conductor 18 of the cable. It is, of course, to be understood that the cable itself constitutes the major portion of the conductors 20 25 and 29, and may be run through the buildin as a single means, havin these three con ucting portions, as descri ed. One side of the bel 27 is connected to a drop lever or trip 30, held in place by the armature 31 of the electro-magnet 28. When this electro-magnet is energized, the l'ever or catch drops and connects with a wire 32 leading to one side of the battery. The other side of thel battery is connected to the bell, as indicated in Fi re 1, and consequently, a local circuit, inclu ing the bell, or other sounding device, and batterly, is established. Y

t is apparent that the member 21 may be controlled by a wire or thread, as indicated I at 33, so that when this thread is touched or broken by the unauthorized entry of a person, or by burning, that the member 21 engages the contact 23 and consequently sounds the alarm.

Further," it is apparent that the member 22 4 may bear against a window sash or door, in-

dicated by the reference charactery 34 in Figure 1, and when said window sash, or other movable member is moved, that the -member 22 engages `the contact 24e, thus sounding the alarm.l I

Further than this', if a burglar attempts to render the alarm system useless by cuttm through the wire lwound Vor 'metal sheat cable, he will Yestablish a connection between the conductor 17 or 18 and the metal sheath,

'which is connected through the conductor 25 to the battery. Thus, the alarm is sounded whenever the cable is cut. l

Further, it is to be noted that if an attempt is made to pry the front metal plate off, that this will cause the contact-member 16, rigidly secured thereto, to engage the metal plate 4 and consequently sound the alarm.

It is, of course, obvious that there are timeswhen it is desired to render this alarm slyl'stem inoperative, as, for linstance, when t e house is in normal use and when people are entering or leavingY the house, or operatlng the windows protected by this system. This is readily accomplished by unlocking the lock or master c ontrol member. However, whenever the occupant desires to throw the alarm into active condition, it is merel necessary for him to lock the lock; hence, 1t is a sim le matter to throw the alarm into orout o use. J

It will be seen further, that a very sim le and highly effective alarm has been provi ed by this invention, and it will be seen that a novel form of master control member or lock has been provided, which4 can not be tamperedl with without setting olf the alarm.

Nothing can stop the alarmafter it has started except entrance to building to the .provided place, such as the magnetic drop Although the invention has been described' in considerable detail, such descri tion is intended as illustrative rather than limiting as the invention may be variously embodied and as the scope of such invention is to be determined as claimed.

I claim 1.'In an alarm system having three conductors,.a lockcomprising an outer plate,

,' a pair of contact members connected to two of said conductors, one of said two conductors being connected to said metal plate, a cam member controlled by said lock for operating said contact members, and means lll . 55 tact with each other lconnected to the third conductor andl adapted to contact with a portion o the lock connected to one of said two conductors, when the lock is pried loose.

2. In an alarm system having a metal sheathed, two-conductor cable, the combination of a lock'having an outer plate, an inner metal plate insulated therefrom, said inner metal plate being connected to themetal sheath of said cable, the outer metal plate having contact brackets normally out of contact with and over-hanging the inner metal plate, said outer metal plate bein connected to one of the two conductors o said cable, a sprin contact member connected to such conuctor, a second spring Contact member adapted to engage said first mentioned contact member and connected to the other conductor of said cable,'and means operated by said lock for operating the Contact members. 3. In an alarm system having a metal sheathed, two-conductor cable, the combination of a lock havin an outer plate, an inner metal plate insu ated therefrom, said f inner metal plate being connected to the metal sheath of said cable, the outer metal plate having contact brackets normally out of contact with and over-hanging the inner metal plate, said outer metal plate bein connected to one of the two conductors o said cable, a, sprin contact member connected to such con uctor, a second spring contact member adapted to engage sai first mentioned contact member and con nected to theother conductor of said cable, and means operated by said lock for operating the contact members, said means comprisin a cam member carried by the barrel of sai lock and adapted for actuation by. a key.

4. A lock for an alarm system comprisin an outer metal plate, threaded ins secure thereto and projecting inward y from the inner face of said metal plate a metal cover metal plate and said contact members and out of contact with both said outer plate and said contact members, an insulating vplate mounted inside of said inner metal plate, spring contact members urged toward contact with each other, and cam means controlled byl said lock for spring contact members, sai inner metal plate being held in osition with reference :go said outer metal p ate by insulating memers, inner metal plate and adapted to'securesaid lock in place.

In testimony that I claim the fore oing I have hereunto set my hand at Rockiord, in the county of Winnebago and State of Illinois. v

EDWARD BELLMAN.

carried by said pins, a pair o contact mem- A i bers carried by said pinsA and spaced inwardly from said outer plate, an inner metal plate positioned between said outer metal plate and said contact members and out of contact with both said outer plate and said contact members an insulating plate mounted inside of said inner metal plate, spring contact members urged toward conand cam means controlled by said loclr for operating said spring contact members.

5. lock for an' alarm system comprisin an outer metal plate, threaded pins secured thereto and projecting inwardly from the Ainner face of said metal plate, a metal cover .carried by said pins, a pair o-contact members carried by said pins and spaced inv and attaching screws carried by said operating said eov

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