US2474757A

US2474757A - Burglary or fire alarm system

Info

Publication number: US2474757A
Application number: US597473A
Authority: US
Inventors: Parilla Daniel
Original assignee: Individual
Current assignee: SEBASTIANO D'AMICO
Priority date: 1945-06-04
Filing date: 1945-06-04
Publication date: 1949-06-28
Anticipated expiration: 1966-06-28

Description

June 1949. D. PARILLA 2,474,77

BURGLARY OR FIRE ALARM SYSTEM Filed June 4, 1945 2 Sheets-Sheet l Inventor Jaw/z Parz'ZZa/ 8,, @Mm m WM June 28, 1949. D. PARILLA 2,474,757

' BURGLARY OR FIRE ALARM SYSTEM Filed June 4, 1945 2 Sheets-Sheet 2 AN b TIM/775M nc 00 AC SUPPLY NOGRAPHIC AFMRA 70$ Inventor :H a

.1702; Z Era/[w Patented June 28, 1949 BURGLARY OR FIRE ALARM SYSTEM Daniel Parilla, Brooklyn, N. Y., assignor of fifty per cent to Sebastiano DAmico, Brooklyn, N

ApplicationJune 4, 1945, Serial No. 597,473

1 Claim.

This invention relates to automatic burglary and fire alarm systems of the type in which the alarm signal is given by radio transmission without the use of line conductors linking up the premises to be guarded with a central alarm receiving station. The invention has for one of its principal objects to provide a simple and effective alarm circuit arrangement which is inexpensive to manufacture and which will operate safely with all types of current and remain in good order even if not under permanent supervision. It is also one of the principal objects to provide radio signals which give the necessary information as to the nature of the alarm, as tothe location of the premises, and as to other useful or helpful data in such a way that this information may be understood by local stations or even by patrol cars on patrol t listening in so that speedyreaction of the authorities may be expected.

Radio alarm apparatus have already been preproposed in connection with burglary and fire alarm systems. However, as abroadcast message cannot be identified in the same way in which a message delivered over lines can be identified, the signals'used had to be of a special character permitting identification. This character of the signals entailed the use of a central receiving station for suchsignals equipped with means for the identification of the signals and the neoessity of using such central stations had the consequence that the transmitter of the alarm apparatus had to cover a relatively large range or distance. This proved to be of disadvantage as alarm signals were thus received by central statlonsin other districts and increased the activities in the central station beyond those needed for thedistrict itself.

It is, therefore, an object of the invention to provide a simple and inexpensive arrangement operating with signals given by spoken words, identifying the district and the premises from which the call originates and giving such additional information, for instance as regards rapid accessibility of a key or the like which may be required or helpful. i

It is a further object of the invention to provide an arrangement of this type which may not be cut in and out by third persons, by means of the switch provided for the owner of the premises in order to prevent an alarm when he enters the premises himself. Such a switch, even if arranged in a recess provided with a locked door, is always located on the outside of the premises to beguarded and it provides for an initiated m 2 person an easy way of access by making the alarm system inoperative.

Still further objects will be apparent from the following detailed description of two embodiments of the invention.

It is, however, to be understood that the fact that only two embodiments of the invention are described is not to be considered as limitative; said embodiments are intended to be illustrative and to foreshadow other ways of carrying the invention into effect. Such other methods, therefore, do not constitute a change of essential features or a departure from the spirit or essence of the invention.

The invention is illustrated in the accompanying drawings in which Figure 1 is a diagram illustrating one modification of the invention Figure 2 is a diagram illustrating a second modification.

Figure 3 is a further diagram illustrating the use of a contact lock.

Figure 4 illustrates lock contacts such as used in connection with the lock box.

In the modification shown in Figure 1, 5 indicates a protective circuit of the usual closed type with a series of normally closed contacts 5 associated with the doors, windows and other protected points.

The circuit 5 is connected with the mains by means of a transformer in whose primary in the modification illustrated is connected with a power supply and control circuit 1, 8 ending in a wall plug 9.

i The circuit 5 moreover contains the winding of an alarm relay II and the spring biased contact I! of a master relay l2.

The alarm relay II by means of its contacts I5, l6 which are closed when the relay is de-energized controls the A. C. power supply and control circuit l3, M which is connected with the mains by the wall plug and which supplies current to the alarm signal producing and transmitting arrangement.

The relay I2 is a master relay whose contact I1 is closed when the relay is de-energized. When the master relay I2 is energized contact I l is opened and breaks the protective circuit permanently even if the alarm contacts are closed again after having once been opened.

The power supply and control circuit l3, ll comprises a time switch 18, a toggle switch I9 of the usual type and the primary winding 20 of a transformer 2| which is provided with secondary windings supplying current to the transmitter to be described below and to the master relay l2.

Thetoggle switch I9 is a hand-operated control means, which switches in or disconnects the signal circuits, so that they are setfor operation in the event that the circuit is opened. This switch is, therefore, operated by the tenant of the premises whenever the place is entered and left to avoid the sending of alarms caused by the tenant himself. It is, of course, located in a place which is not easily accessible to intruders, but is easily accessible to the tenant or his representatives himself. In connection with this switch, the time switch I 8 is used and set for a time which will permit the leaving of the premises without causing an alarm. The provision of the time switch permits to arrange the switch within the guarded premises and thus allows to dispense with the usual arrangement using a master switch outside of the premises to be guarded which may be used also by persons who have the necessary inside information.

A

branch circuit

22, 23 branching oil! from the A. C. power supply and control extension I3, It includes the armature and field coil 24, 25 of a motor driving the turn table 26 of a phonographic apparatus indicated generally by the reference 30. The latter also comprises a pick-up 28 connected with the radiotransmitter indicated'generally by 3|. The phonographic apparatus 30 is of the usual type and its record bears the message to be transmitted in open words, which is preferably repeated several times, so that it is sent continuously during a certain number of minutes. It may be sent out permanently by using an endless strip or ribbon with a closed sound track returning in itself instead of a disk shown in the diagram. However, as a rule alarm messages of a, limited duration are preferred as they are less likely to be the cause of trouble,

The message states in a simple spoken words the nature of the alarm, the location of the premises, if necessary the district to which the premises belong, and any further information considered as helpful such as the location of a key to the premises or the like.

The pick-up 28 is connected with a transmitter 3| of a conventional construction and design which is indicated diagrammatically by the amplifier tube 32, the modulator tube 33, the oscillator tube 34 and the antenna 35. All these tubes and their auxiliary equipment are supplied with a D. C. current furnished by means of rectifiers and impulse flattening chains indicated diagrammatically at 36 and 31, respectively, which are furnished by the primary of the transformer 2 forming part of the circuit l3, l4.

The details of this current supply and of the transmitter itself are not part of the invention and are, therefore, only indicated diagrammatically or are not shown at all.

In order to reduce or eliminate the possibility of tampering with the equipment, the entire equipment shown with the exception of the protective circuit 5, and the antenna may be enclosed in a wall box which is inaccessible from without and closed by a door which is itself guarded by the contacts of the protective circuit. The cable carrying the mains to the box into which the wall plug 9 is inserted and the cable leading to the antenna and the latter may be arranged in such a fashion that they are inaccessible from the outside. Any person wanting to cut off the current or to make parts of the alarm system inoperative has first to Pa s alarm contacts which are operating the alarm. In this way tampering tective circuit when, after setting switch l3, he has to'pass and to open several alarm contacts in the process of leaving the premises. When enterlng the premises the'tubes of the transmitter which are indirectly heated provide a time lag of about 30 seconds which in most cases is sufllcient to permit operation of the switch I! after opening an alarm.

Once the alarm circuit is completely set by means of switch I! and time switch l8 any transitory opening of the contact 6 will cause the energizing of the master relay l2 and a permanent breaking of the circuit 5 at contact ll, thereby keeping relay ll deenergized, and contacts I5 and I 6 closed.

Closure of these contacts completes the circuit l3, I4 and

branch circuit

22, 23. As the branch circuit contains the windings 24, of the motor of the phonographic machine 30, the latter will be set into motion and the pick-up is actuated.

The currents induced in the pick up, after having been amplified, are modulating the carrier frequency which is radiated by the antenna 35.

40 As will be clear, the arrangement, if properly mounted and located, can be made completely secure against any interference and will furnish an alarm which when broadcast on the wave length used by the police or fire brigade can be picked up by any local station or any police car.

The modification shown in Figure 2 illustrates an embodiment of the invention which operates on D. C. and A. C. and can, therefore, be used as a standard equipmentor as an equipment operating on two sources of current supply provided for normal operation of and for emergency purposes, respectively. It also shows a further means for excluding alarms caused by the tenant of the premises.

The parts, members and arrangements already described and similar to or identical with those used in Figure 1 are designated with the same reference numerals. The connection with the mains is again made by means of a wall plug 9 0 with the contacts of which the protective circuit 5 may be directly connected. This circuit includes alarm switches 6, alarm relay II and master relay l2 as already described.

The circuit l3, H in this case is again controlled by the contacts l5, l6 and it includes the current supply branch lead 38, which may be connected directly with the filament circuit of the

tubes

32, 33, 34.

This circuit l3. It comprises the electric lock box 39 which takes the place of the control switch and time switch shown in Figure 1. This box contains contacts 40, ll which are operated by a key 42. The box is preferably provided with means making it impossible to operate the lock by tools inserted into the key hole and it may time switch provides a lag of time of such duration that the tenant does not operate the probe guarded in the usual manner by contacts forming part of the alarm circuit against attempts to open it by force and against damage due to the use of a tool. The box as indicated in Figure 4 contains contacts which are closed by the key by using the bolt locking the box for this purpose. When the key is turned the contacts 40, 4| are closed by the bolt moved by the key. The circuit [3, I4 is thereby closed and is ready for operation when relay ll deenergizes and thereby closes contacts l5, IS The circuit l3, i4 is connected with the

circuit

22, 23 of the motor 24, 25 of the phonographic apparatus 30 and the phonograph is, therefore, operated as soon as the alarm relay is deenergized. The pick up 28 again influences the grid of an amplifier tube 32 whose output is fed to the modulator tube 33 cooperating with the oscillator tube 34 and the antenna 35.

The winding of master relay I2 is inthis case connected with the circuit l3, M by means of a conductor 43- so that it can be influenced from the lock box. Energization of this relay keeps the closed alarm circuit 5 permanently open and actuates the alarm apparatus.

The operation need not be described as it is practically the same as that already described with reference to Figure 1, the difference being mainly that in this modification the use of the electric lock box brings the circuit l3, l4 into operation. I

It will be seen from the above that the arrangement is vry simple and is adapted to serve under various circumstances. It is to be understood that many details may be changed or modiiied without in any way departing from the essence and spirit of the invention which mainly consists in the combination of parts, members and elements hereinafter mentioned in the claim rather than in the elements, part or members themselves;

I claim:

An alarm circuit comprising a radio transmitter, a rectifier arrangement for supplying the same with rectified current, a phonographic device with a driving motor for modulating the transmitter, a central A. C. power supply and control circuit with three branch circuits, the first branch circuit including the motor of the phonographic device, the second branch circuit including a transformer primary, an electromagnetic contact device and a time operated switching device in said A. C. power supply and control circuit, controlling the two aforementioned branch circuits only, a master relay circuit having a secondary winding coupled with the transformer primary, a normally closed protective circuit containing alarm contacts and an alarm relay, the latter operating the aforesaid electromagnetic contact device, means for providing said protective circuit with current, said means including thethird branch circuit, branching oil from the central A. C. power supply and control circuit and a transformer, a master relay in said master relay circuit, and contacts controlled by said master relay, opening the protective circuit when the master relay is energized.

DANIEL PARILLA.

REFERENCES CITED 7 The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 665,801 Rough Jan. 8, 1901 942,508 Menkin Dec. 7, 1909 1,365,693 Hess Jan. 18, 1921 1,497,194 Norden ct al June 10, 1924 2,022,991 Walter Dec. 3, 1935 2,234,598 Howton Mar. 11, 1941 2,252,710 Foss Aug. 19, 1941 2,346,171 Laford Apr. 11, 1941 FOREIGN PATENTS Number Country Date 14,026 Australia June 23, 1928'