US1868884A - Alarm system - Google Patents

Description

Julyv 26, 1932. H CHASE 1,868,884

ALARM SYSTEMS Filed June '7, 1922 Le/and hase Patented July 26, 1932 UNITED STATES PATENT OFFICE LEILAND H. CHASE, OF NORTHAMPTON, MASSACHUSETTS, ASSIGNOR TO HOLMES ELEC- TRIC PROTECTIVE COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK ALARM SYSTEM Application filed June 7,

i circuits being associated through the initiatmg circuit with the protection circuit at all times. In the invention herein shown and described, the protection circuit is of the wellknown type in whicha change in resistance therein deiiects a galvanometer relay needle for the purpose of closing the initiating circuit and causing closure of an alarm circuit. The primary alarm circuit includes a loud sounding gong located outside the protected premises and is adapted to be associated with the protection circuit during night time. The secondary alarm circuit includes a buzzer located conveniently within the building, this circuit being associated with the protection circuit during the day time. The buzzer circuit serves several purposes, as will hereinafter appear, but its main function is to act as a quiet alarm so that if a burglar tampers with the protection circuit during' the day preparatory to a night raid, the buzzer will notify the proprietor without attracting undue attention.

Another feature of the invention relates to the means provided whereby an authorized person may substitute the buzzer circuit for the gong circuit prior to' entering a building protected by the invention, but an unauthorized person can enter only by sounding the gong Other features and advantages of the in vention will appear from a consideration of the following description taken in conjunction with the accompanying drawing which shows a diagrammatic view of a circuit embodying the invention.

1922. Serial N0. 566,528.

Referring to the drawing, theprotection circuit includes a galvanometer relay 1, a battery 2, a four-pole doublefthrow switch 3, a plurality of alarm traps, and the permanent protective wiring commonly employed on the doors, windows, etc. on the premises. The network 4, for example, may be the common type of conducting toil strung as a border on the show window of the store, while the network 5 may be strung in the walls of a safe or vault inside the store. The traps 6 and 7, some normally opened and others normally closed, represent switches adapted to be operated by the opening of doors or windows disposed at various parts of the building.v Two other alarm traps 8 and 9, respectively, areA also provided for purposes hereinafter described. The protection circuit may be traced from' one side of battery 2, galvanometer relay 1, network 4, closed alarm traps 6, conductor 10, resistance 11, switch 3, conductor 12, alarm traps 7, conductor 13, switch 3, conductor 14;, network 5 traps 8 and 9 and conductor 15 to the other side of any change in theresistance of the protection circuit, caused by a 4break or short circuit therein, or due to any other cause, will cause a deflection in the needle of the galvanometer relay 1, causing the needle to engage with one oi" a pair of contacts disposed at either side thereof.

The initiating circuit associated with 'the galvanometer relay contacts is in reality a duplex circuit having primary and secondary branches comprising primaryfand secondary alarm circuits respectively which are adapted to be connected singly and selectively with the protection circuit. This initiating circuit with its associated primary and secondary alarm circuit-s includes a source of current 16, a double wound relay 17 a lock switch 18, gong keyq7 19, gong 20 and buzzer 21. The lock switc 18 is provided for the purpose of connecting either the gong or buzzer into the initiating circuit. This lock switch consists of an ordinary break switch adapted to a lock, thus providing means for the operation of this switch by a key. Such a switch is preferably located outside of the building but has no connection with the ordinary locks on the doors. As shown in the drawing, the contact arm of lock switch 18 is in engagement with contact 22 and the gong 2O is connected iii the initiating circuit. One leg of this initiating circuit is completed through battery 16, conductor 23, galvanometer relay contact, galvanoiiieter relay pointer, conductor 24, left-hand winding of relay 17, conductor 25, contact 22, lock switch 18 to the other side of battery 16. When this circuit is established, armature 26 of relay 17 will be attracted, closing contact 27. The primary alarm circuit including the gong 20 is traceable from battery 16, lock switch 18, lock contact 22, conductor 25, armature 26 of relay 17, contact 27, conductor 28, gong 20, conductor 29. key 19, and conductor 31 to the other side vof battery 16.

The right-hand winding of the relay 17 is bridged across the gong circuit and is energized while the gong is ringing. This wind ing is for the purpose of locking the contact closed once, the relay 17 is energized by the closing of the galvanometer relay contacts. Once the contact 27 is closed by an open or short circuit in the protection circuit, it can only be opened by moving the movable arm of lock switch 18from contact 22 -or by opening the key 19.

The trap 8, referred to above, is mechaiiically associated with the lock switch 18, while the traps 9 are fixed' to the cover of the boX containing the gong. Since one leg of the protection circuit passes through these traps, it is impossible to disconnect the gong er the lock switch without sounding an alarm.l

Y The buzzer 21 is connected in circuit through the double-throw switch 3 and also through a contact 32 on the lock switch 18. As previously stated, this buzzer is adapted to be connected in the circuit during the day in order to summon the proprietor if the attachments are tampered with While the store is occupied. Another object of the buzzer is to give warning as to how the switch 3 is set. and also as to the position of the lock switch 18. The buzzer also provides a means for testing the gong batteries without actually operating the gong. For example. with the switch 3 in the position shown in the drawing, in order to test the battery 16. the contact arm of lock switch 18 is moved into engagement with the contact 32. The buzzer circuit may then be traced from battery 16. lock switch 18 and contact 32 thereof, buzzer 21, conductor 33, switch 3, conductors 34 and 31 to the other side of battery 16.

When the premises are open the lock switch contact 32 will be closed and double-throw switch 3 will be thrown to the right. closing all right-hand contacts and openingvall lefthand contacts. The secondary or buzzer alarm circuit will then be operatively connected with the protective circuit. When the protective circuit is ruptured or otherwise disturbed during the day, the galvanometer relay will function and the alarm circuit will be established from battery 16, ai'm and contact 32 of lock switch 18, buzzer 21, conductor 33, switch 3, conductors 35 and 24, galvanometer relay needle, galvanoineter relay contact, conductor 23 to the other side of battery 16. When the right-hand contacts of switch 3 are closed the yprotective circuit is very similar to that prevailing when the left-hand contacts are closed, and may be traced from battery 2, galvanometer relay 1, network 4, conductor 36, switch 3, conductor 38, resistance 1,1, third pole of switch 3, fourth pole of switch 3, conductor 14, network 5, traps 8 and 9 and conductor 15 to the other side of battery 2. It will be n oted that traps 6 and 7 are not included in this circuit, but if these attachments are tampered with while the buzzer is in circuit, this fact will become known when the gong circuit is substituted at closing time.

If the premises are closed and the gong circuit is set for the night, as shown in the drawing, and it is desired to open up, the

lprocedure is as follows: a key is inserted in the lock switch 18, turning the switch and disconnecting the gong circuit at contact 22 and closing the buzzer circuit at contact 32, as previously traced. The proprietor may now enter the premises without sounding the gong, but nevertheless the buzzersounds until the switch 3 is thrown to the right. lVhen this is done the protection circuit .is completed and is set for an alarm. Thus, in opening the premises an authorized person is enabled to cut out the loud-soundiiig gong on the outside of the building and substitute therefor the buzzer inside the premises. This feature is to prevent needless 'ringing ofthe gong should the protection circuit be upset while an authorized person is on the premises. At closing time the procedure is reversed. The switch 3 is irst thrown to the left-liand position. This switches the protective attachments into circuit and closes the buzzer circuit, thus giving warning that the gong circuit is not yet cut in. The buzzer continues to sound until the lock switch is turned to open contact 32 and close contact 22, thus breaking the buzzer circuit and cutting in the gong circuit. If the protection circuit is now opened or short-circuited, the

gong will sound through the proper functioning of the galvanometer relay. Once the gong circuit is complete it can only be opened by turning the lock 18 to move the movable element off contact 22 or by a person gaining entrance to the building and opening key 19. By the position of the pointer of the galvanometer relay it is possible to see whether the attachments have been properly set.

Certain changes in the details of construction herein shown and described will be obvious to those skilled in the art and accordingly it is not intended to limit the invention except as deiined in the appended claims.

The invention claimed is:

l. An alarm system comprising a closed protective circuit, a galvanometer relay in said circuit and o-perated by a change in the resistance of said circuit, a buzzer circuit for day operation, a gong circuit for night operation, said circuits being controlled at a normally open contact of said relay, a two position key controlled switch in one position closing a break in said buzzer circuit and the other position closing a break in said gong circuit, alarm traps, a two position switch controlling said closed protective circuit and in one position including said traps in said network and in the other position excluding them while maintaining said protective circuit closed, a second circuit for said buzzer, including the contact of said key switch connected to the buzzer, the buzzer and the contacts of the two position switch which are closed when said switch is in its position including said traps. y

2. A burglar alarm system comprising a closed protective circuit, an electro-responsive device in said circuit, a manual switch having a night position and a day position, a primary alarm circuit including a signal device for night operation and a secondary alarm circuit including a signal device for day operation, each of said circuits connected to a separate terminal of said switch, said switch placing either of said alarm circuits in operative relation to said electro-responsive device, trap switches, a multi-polar switch having a night position and aI day position, connections between said protective circuit and contacts of said multi-polar switch for including said trap switches in said closed protective circuit when the multi-polar switch is in the night position and for eX- cluding said trap switches while maintaining said protective circuit closed when said multipolar switch is in the day position, circuit connections between said multi-polar switch and said last-mentioned signaling device for causing its operation when said multi-polar switch is in its night position and said manual switch is in its day position.

3. A burglar alarm system comprising a closed protective circuit associated with the area to be protected, a galvanometer relay in said circuit, a key controlled switch having a night position and a day position, a primary alarm circuit including a gong for night operation, said gong being located outside of the protected area, and a secondary alarm circuit including a buzzer for day operation, said buzzer being located inside the protected area, each of said circuits connected to a separate terminal of the key controlled switch, said switch placing either of said alarm circuits in operative relation to said galavanometer relay trap switches, a multipolar switch having a night position and a day position, connections between said protective circuit and contacts of said multipolar switch for including said trap switches in said closed protective circuit when the multi-polar switch is in its night position and for excluding said trap switches while maintaining said protective circuit closed when the multi-polar switch is in its day position, connections between said secondary alarm circuit and said multi-polar switch for causing operation of said buzzer when said multipolar switch is in its night position and said key controlled switch is in its day position. In witness whereof I hereunto subscribe my name this 3rd day of June, A. D. 1922.

LELAND H. CHASE.

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