US3636546A - Alarm system transmitter - Google Patents

Abstract

An alarm system having a security circuit loop which passes through an area to be protected and an alarm circuit loop for transmitting alarm signals to a monitoring center, including means for generating a plurality of discrete coded signals indicating the operation of an on-off switch located outside the protected area, a discontinuity in the security circuit and any authorized or unauthorized entry into the protected area and distinctively identifying the protected area.

Description

Unite States Patent [451 Jan. 18, 1972 Lomonaco [54] ALARM SYSTEM TRANSMITTER [72] Inventor: John S. Lomonaco, 429 South Victory Blvd, Burbank, Calif. 91502 [22] Filed: July 2, 1968 I [21] Appl. No.: 741,953

[52] 0.5. CI ..340/276, 340/293, 340/409 [51 ..G08b 25/00 [58] Field of Search ..340/215, 309, 276, 274, 213,

[56] References Cited UNITED STATES PATENTS 1,868,884 7/1932 Chase ..340/276 2,492,432 12/1949 Laford... 3,085,235 4/1963 Ward..... 3,484,771 12/1969 Falck, Jr. ..340/215 X SECURITY LOOP 7'0 MO/V/ TOR/N6 CEA/ TER Kissinger et al ..340/309 X Muether ..340/309 Houghton ..340/276 Chase et al. ..340/276 Primary Examiner-Donald J. Yusko Assistant Examiner-Scott F. Partridge Anorney-Rober1t Louis Finkel ABSTRACT secoua MOTOR 8 Claims, 2 Drawing Figures N/GH TT/ME DA YT/ME 3&1 54' ALARM LOOP ALARM SYSTEM TRANSMITTER This invention relates generally to alarm systems and more particularly to alarm systems of the type wherein a security circuit loop which passes through an area to be protected is energized so as to conduct electrical current, and any break in the circuit during such energization period produces an alarm signal. Typically, the alarm signal is transmitted through a conventional alarm circuit loop such as a McCulloh loop to a monitoring center where constant surveillance is carried on by persons and/or apparatus. Visual and auditory alarm signals can also be given at the secured area itself to alert security guards, policemen and the like of the break in the security loop.

The drawbacks and inefficiency of such a system are numerous because of the inability of the person at the monitoring center to discern between authorized entry into the secured area on the one hand by the owner or security guard, and unauthorized entry into the secured area on the other hand by a trespasser or the like, since both types of entry necessarily require the opening of a door or window through which the security loop passes. Even in those systems which provide a way for the owner or security guard to disarm the alarm before entering the secured area, there is still no way for the person at the monitoring center to know of the disarming. Even if the system provides a way to indicate such a disarming, there is still the problem of distinguishing between disarming which is authorized and disarming which is not authorized.

Accordingly, it is a primary object of the present invention to avoid the above-mentioned problems of the prior art and to provide a new and improved alarm transmitter capable of distinguishing between entry into the secured area by authorized personnel and entry by someone other than the owner or security guard. Another primary object is to provide a first alarm signal to identify such an authorized entry and a second alann signal to identify such an unauthorized entry. A related object is to provide first and second alarm signals of the foregoing character which are coded to indicate the location of the particular security circuit involved.

A further object of the present invention is to provide an alarm transmitter of the foregoing character which is inexpensive, simple, and reliable, and which cannot easily be circumvented by tampering with any of the parts.

Another object is to provide a detecting and transmitting device which is adaptable for use with conventional security loop circuits and with conventional alarm circuit loops such as the McCulloh loop, such adaptability achieving advantages already mentioned without requiring the time and expense of installing new security loop circuits or new alarm circuit loops.

Another object is to provide an alarm transmitter of the foregoing character having a daytime and nighttime setting, wherein a break in the security loop circuit during the daytime setting produces no alarm signal, but wherein such a break during the nighttime setting produces an alarm signal. A related object is to provide a key switch which establishes a daytime setting when turned off and a nighttime setting when turned on.

A more specific object is to provide alarm transmitter of the foregoing character which includes a first circuit means for generating a first alarm signal whenever the key switch is turned on and also whenever the key switch is turned off, the signal being one cycle of a code which identifies the location of the particular security circuit involved. A related object is to provide a second circuit means for generating a second alarm signal whenever a break in the security circuit occurs while the key switch is turned on, the second signal being a plurality of cycles of the code which identifies the location of the particular security circuit involved.

Another object is to provide an alarm transmitter of the foregoing character which can be easily reactivated whenever there is an unauthorized entry which breaks the security circuit loop. A related object is to provide for reactivation in that instance by turning the key switch to off, closing the door or window through which entry occurred in order to close the security circuit loop, and then turning the key switch back to Still another object is to provide an alarm transmitter of the foregoing character which detects and identifies intermittent security loop breaks caused by power failures, electric eye interruptions, and the like, and which also distinguishes alarm signals resulting from improper closing of the security loop circuit.

A further object is to provide a method for protecting a secured area which includes generating and transmitting different coded alarm signals identifying and distinguishing between operation of the on-off key switch, an unauthorized entry which breaks the security loop, improper closing, and intermittent security loop breaks such as power failure or electric eye interruption.

The invention also comprises novel details of construction and novel combinations and arrangements of parts, which will more fully appear in the course of the following description. The drawing merely shows and the description merely describes a preferred embodiment of the present invention which is given by way of illustration or example.

In the drawing:

FIG. 1 is a top plan view of an alarm transmitter incorporating a preferred embodiment of the invention, the parts being shown as they are when the key switch is in the off or daytime position, the electrical interconnections not being shown; and

FIG. 2 is a diagram of the electrical circuitry of the embodiment shown in FIG. 1, the switches being shown as they are when the key switch is in the off or daytime position.

Referring to FIGS. 1 and 2, a plate 10 is provided on which are mounted a first cogwheel or code wheel 12, a first spur gear 14 proportionally coupled thereto through a pinion 16 attached to the first cogwheel, and a first motor 18 with an output shaft 19 for turning the first code wheel and the first spur gear, the motor being mounted on the underside of the plate 10. A plurality of teeth is arranged in a predetermined pattern around the circumference of the first code wheel 12 for periodically engaging operating arms 20, 20a of an alarm signal switch S6 mounted on the plate 10. A pin 22 is located near the circumference of the first spur gear 14 to periodically engage operating arms 24, 26 of switches S5 and S3, S4, respectively, the three switches also being mounted on the plate 10 and normally being closed, closed, and open, respectively. When the first motor 18 is energized, the rotation of the first code wheel 12 and the first spur gear 14 therefore periodically actuates switches S3-S6 at a predetermined rate and sequence, as will be described in detail hereinafter.

On another portion of the plate 10 is mounted a similar arrangement of elements including a second cogwheel or code wheel 28 having the same pattern of circumferential teeth as the first code wheel 12, a second spur gear 30 proportionally coupled thereto through a pinion 32, and a second motor 34 with an output shaft 35 for turning the second code wheel and the second spur gear, the motor being mounted on the underside of the plate 107 However, in this instance the teeth of the second code wheel 28 periodically engage operating arms 36, 36a of an alarm signal switch S7 mounted on the plate I0. A pin 40 on the second spur gear 30 periodically engages operating arms 42, 44 of switches S1 and 52, respectively, which are normally connected to lines 46 and 48, respectively. When the second motor 34 is energized, the rotation of the second cogwheel 28 and the second spur gear 30 periodically actuates switches S1, S2, and S7 at a predetermined rate and sequence, as will be described in detail hereinafter.

The purpose of the alarm switch S6 is to open and/or close one or more electrical circuits to provide an electrical signal at a remote location. Various electrical switches are suitable for this use and a preferred switch, typically known as a McCulloh brush, is illustrated herein. The McCulloh brush switch S6 has two sets of contacts, one set being normally closed and one set being normally open. The arm 20 and switch member form the normally closed set. The arm 20a and switch member 81 form the normally open set. In the embodiment illustrated in FIG. rotation of the code wheel 12 will first open the normally closed set by engaging the arm 20, and then close the nonnally open set by engaging the arm 20a. The alarm switch S7 may be identical to the alarm switch S6, with arm 36 and switch member 82 forming the normally closed contact set and with arm 36a and switch member 83 forming the normally open contact set. Referring to FIG. 2, switch member 80 is connected to terminal No. 6 of a terminal board 21, arms 20 and 200 are connected to switch member 82 by line 21a, switch members 81 and 83 are connected to circuit ground, and anns 36 and 360 are connected to terminal No. 7. Terminal No. 8 is connected to circuit ground. Various arrangements can be utilized for connecting the alarm transmitter to the remote monitoring center. The transmitter as illustrated is particularly adapted for the McCulloh loop which incorporates ,a leased telephone line in the alarm loop, with telephone line conductors connected at terminals No. 6 and No. 7, and with the telephone line ground connected to terminal No.8.

Referring to the electrical circuitry in FIG. 2, an on-ofi' key switch 49 is provided for turning the alarm system to an off or daytime position and to an on or nighttime position, the fonner connecting terminals 50 and 52 to terminals 54 and 56, respectively, and the latter connecting terminals 50 and 52 to terminals 58 and 60, respectively. The first motor 18 can be energized by a power source such, as a battery 62 acting through a loop passing through board terminal No. l to a line 63 through switch S1 to the positive lead of the first motor 18 and then either through closed switch S3 and terminals 58, S (nighttime), or through closed switch 85, board terminal No. 3 and terminals 54, 50 (daytime), and then in both instances back to the battery through board tenninal No. 4. A diode 63a is provided between board terminal No. l and switch S1 to prevent reverse motor operation in the event a battery is connected backward.

The path by which the second motor 34 can be energized is determined by the position of a relay switch 61 which is actu-' ated by a relay 64. Under normal daytime or nighttime positioning of the key switch 49, the relay 64 remains energized the daytime positioning providing current from the battery 62 through board terminal No. 1, terminals 52, 56, and through board terminal No. 2 to the relay, and the nighttime positioning providing current from a power source such as a battery 66 through a security loop circuit 68 through board terminal No. 2 to the relay. A diode 69 is provided between board terminal No. 2 and the relay 64 for the same purpose as diode 63a. in both daytime and nighttime settings, the negative lead of the relay is connected back to the negative terminals of the batteries 62, 66 through board terminal No. 4.

The security loop circuit 68 is typically connected in series and passes through various door and window junctions and the like, the opening and/or breaking of such doors or windows causing a break in the security loop circuit. It is to be noted that when the key switch 49 is on the nighttime setting, any break in the security loop circuit 68 will deenergize the relay 64, while during the daytime setting such a break would have no effect upon the relay. The alarm system is therefore deactivated throughout the daytime setting and activated throughout the nighttime setting. During the daytime setting, relay 64 is energized by battery 62, and during the nighttime setting, relay 64 is energized by battery 66. The two batteries normally have the same rating, typically 6 volts.

When the relay 64 is energized and the moving arm of relay switch 61 is connected to a line 70, the second motor 34 can be energized by the battery 62 acting through a loop passing through board terminal No. l to the positive lead of the second motor through switch S], a line 46, line 70, and the relay switch 61. When the relay 64 is not energized and the moving arm of relay switch 61 is connected to a line 74, the second motor 34 can again be energized by the battery 62, but the loop passes through switch S2, line 48, closed switch S4, and the relay switch 61 before connecting to the positive lead of the second motor. The negative lead of the second motor 34 hasthe same connective path back to the negative battery terminal as does the negative lead to the relay 64.

The sequence of operation of the alarm system when there is no break-in is as follows: when the owner prepares to leave the premises such as in the evening or for the weekend, he activates the security loop circuit 68 by operating the key switch 49 to the on or nighttime position. The first motor 18 is energized and begins rotating the first code wheel 12 and the first spur gear 14. In the illustrated form of the invention, the teeth on the pinion l6 and the first spur gear 14 are selected to provide two revolutions of the first code wheel 12 for every one revolution of the first spurgear. The first motor 18 is deenergized when the pin 22 engages the operating arm 26 of switch S3 and opens it, such engagement occuring after the first spur gear has rotated 180 and the first code wheel has rotated 360. During such rotation, the ten teeth on the circumference of the first code wheel 12 each successively engage the operating arms of switch S6 thereby generating an alarm signal which is transmitted to the alarm circuit loop. The number and spacing of the teeth are only exemplary, as is the number of cycles of the alarm signal, so long as the number and spacing of the teeth are codified to identify the particular secured area involved and the number of cycles of the coded alarm signal generated and transmitted identifies the operation of the key switch 49.

When the owner returns to the protected premises, such as in the morning, he operates the key switch 49 to the off or daytime position and thereby deactivates the alarm system. Such operation energizes the first motor 18, the first code wheel 12 and the first spur gear 14 being rotated another 360 and 180, respectively, at which point the pin 22 engages the operating arm 24 of switch S5 and opens it to break the circuit. It will therefore be appreciated that whenever one cycle of the coded alarm signal is generated and transmitted, the monitoring center knows that the key switch 49 has been operated by personnel using the authorized key in the key switch.

The sequence of operation of the alarm system when there is a break-in during the on or nighttime setting is as follows: the unauthorized entry breaks the security loop circuit 68 and deenergizes the relay 64, thereby causing the relay switch 6] to change positions and connect the positive lead of the second motor 34 to line 74. The second motor 34 thus becomes energized and begins rotating the second code wheel 28 and the second spur gear 30. In the illustrated form of the invention, the teeth on the pinion 32 and the second spur gear 30 are selected to provide four revolutions of the second code wheel 28 for every one revolution of the second spur gear. The second motor 34 is deenergized when the pin 40 engages the operating arm 44 of switch S2 and disconnects it from line 48 to break the circuit, such engagement occurring after the second spur gear has rotated 270 and the second code wheel has rotated l,080 (three revolutions). During such rotation, the ten teeth on the circumference of the second code wheel 28 each successively engage the operating arms of alarm signal switch S7 thereby generating an alarm signal which is transmitted to the alarm circuit loop.

it is important that the alarm signal generated and transmitted as a result of a break-in be codified to indicate location, and that it be distinguishable from the alann signal used to identify operation of the key switch 49. The preferred embodiment provides for the same codified signal in each instance, i.e., the number and spacing of the teeth on the first and second code wheels 12, 28 are identical, but as indicated above, a break-in produces three cycles of the alarm signal.

After there is a break-in, the key switch 49 is changed to the daytime setting by the owner or a security guard, thereby energizing the relay 64, connecting the moving arm of relay switch 61 to the line 70, and energizing the second motor 34. The energized second motor 34 rotates the second code wheel 28 through 360 and second spur gear 30 through until the pin 40 engages the operating arm 42 of switch S1 to disconnect it from line 46 and break the circuit. Immediately following the one-cycle alarm signal is another signal, the second being generated by the first code wheel 12 and first spur gear 14 as they are rotated by the first motor 18, the motor being energized through switch S] which was reconnected to the battery 62 when switch S1 was disconnected from line 46. Therefore, when the monitoring center receives a two-cycle alarm signal following a break-in, the person at the center is on notice that the key switch 49 has been changed to the daytime setting. The gap in the security loop circuit 68 is then closed or remedied by the owner or security guard, after which the alarm system is reactivated by operating the key switch 49 from off to on, notice of such key switch operation being provided by generation and transmission of a single cycle of the coded alarm signal in the same manner as previously described.

The alarm system provides an indication of an intermittent break which may occur when during a nighttime setting, as when an electric eye beam or the like is interrupted, or when there is a weak or poor connection in the system, or when there is a power failure, or when a door is opened and then closed. Under these circumstances, the second code wheel 28 will turn l,440 (four revolutions) and the second spur gear 30 will turn 360 (one revolution). The first three revolutions of the second code wheel 28 occur because of the break or opening of the security loop circuit 68 and the fourth revolution occurs because the reclosing of the security loop circuit energizes the relay 64 and thereby energizes the second motor 34. The second motor 34 is deenergized when the operating arm 42 for switch S1 is engaged by the pin 40 and disconnects switch 81 from line 46, the result being an automatic resetting of the alarm system to the nighttime condition.

If there is an improper closing, such as a door being left open when the owner locks up for the evening and turns the key switch 49 to the nighttime setting, the usual generation and transmission of the single cycle coded signal are immediately followed by the generation and transmission of the three-cycle coded signal identified with unauthorized entry during the nighttime condition. Therefore, when the monitoring center receives a four-cycle signal, the person monitoring knows that a door or window has not been closed and can take the necessary steps to close it. Such correction involves the same steps as for resetting the system following a break-in as previously discussed.

It will therefore be apparent to those skilled in the art that an alarm system is provided which includes a first circuit means for generating a first coded alarm signal whenever the key switch 49 is operated, and includes a second circuit means for generating a second coded alarm signal clearly distinguishable from the first whenever an unauthorized entry oc curs during the nighttime setting. Furthermore, intermittent breaks in the security loop circuit 68 are detected without having to manually reset the nighttime condition and, in addition, improper closings generate a coded alarm signal which is distinguishable from the key switch operation signal and the break-in signal, thereby adding to the novelty and usefulness of the invention.

Although an exemplary embodiment of the invention has been disclosed and discussed, it will be understood that other applications of the invention are possible and that the embodiment disclosed may be subjected to various changes, modifications and substitutions without necessarily departing from the spirit of the invention.

lclaim:

1. In an alann system having a security circuit loop passing through an enclosed area to be protected, power supply means for supplying current to the security circuit loop, and an alarm circuit loop for transmitting alarm signals to a monitoring center monitoring a plurality of such alarm systems, an improvement comprising:

an on-off circuit loop connected electrically to said power supply means in parallel with said security circuit loop, and containing a selectively operable on-off switch located outside the area to be protected adapted to close and thereby energize said on-off circuit loop when said switch is in its off position;

first circuit means for sensing operation of said on-off switch, and for generating a first alarm signal to indicate such operation and to identify the particular system being monitored in which said operation takes place; second circuit means for sensing a discontinuity in said security circuit loop, said second circuit means being adapted to generate a second alarm signal in response to a discontinuity in said security circuit loop when said on-off switch is in its on position, and thereupon to generate a third alarm signal when said on-off switch is operated to its off position, said second and third alarm signals identifying the particular system being monitored in which said discontinuity exists, and said second alarm signal being distinguishable from said first alarm signal; and

transmitting means for coupling said first, second and third alarm signals to the alarm circuit loop.

2. An apparatus as defined in claim 1 in which said transmitting means includes a first alarm signal switch coupled to the alarm circuit loop, and

in which said first circuit means includes a first code wheel for actuating said first alarm signal switch and a first motor for driving said first code wheel, and

in which said on-ofi switch includes means for energizing said first motor when said on-off switch is operated from on to off,

said first circuit means further including first switch means for deenergizing said first motor when said first alarm signal has been generated and transmitted through said first alarm signal switch to the alarm circuit loop.

3. Apparatus as defined in claim 2 in which said first circuit means further includes first gear means coupled to said first code wheel for actuating said first switch means to deenergize said first motor when said first alarm signal has been generated and transmitted through said first alarm signal switch to the alarm circuit loop.

4. Apparatus as defined in claim 2 in which said on-off circuit loop includes means for energizing said first motor when said on-off switch is operated from off to on, with said first switch means deenergizing said first motor when said first alarm signal has been generated thereby and transmitted through said first alarm signal switch to said alarm circuit loop.

5. Apparatus as defined in claim 4 in which said first switch means include two switches in parallel with said first motor, one of which is closed by said on-off switch being operated from on to off, and the other of which is closed by said on-off switch being operated from off to on.

6. Apparatus as defined in claim 2 in which said transmitting means includes a second alarm signal switch coupled to the alarm circuit loop, and

in which said second circuit means includes a second code wheel for actuating said second alarm signal switch, a second motor for driving said second code wheel, and means for energizing said second motor when said on-off switch is on and said discontinuity is sensed, said energizing means including second switch means for deenergizing said second motor when said second alarm signal has been generated and transmitted through said second alarm signal switch to the alarm circuit loop.

7. Apparatus as defined in claim 6 in which said second circuit means further includes second gear means coupled to said second code wheel for actuating said second switch means to deenergize said second motor when said second alarm signal has been generated and transmitted through said second alarm signal switch to the alarm circuit loop.

8. An apparatus as defined in claim 1 in which said second circuit means is adapted to generate a fourth alarm signal in the event the security circuit loop, once having been disrupted, is again closed while the on-off switch is still in its on position.

Claims (8)

1. In an alarm system having a security circuit loop passing through an enclosed area to be protected, power supply means for supplying current to the security circuit loop, and an alarm circuit loop for transmitting alarm signals to a monitoring center monitoring a plurality of such alarm systems, an improvement comprising: an on-off circuit loop connected electrically to said power supply means in parallel with said security circuit loop, and containing a selectively operable on-off switch located outside the area to be protected adapted to close and thereby energize said on-off circuit loop when said switch is in its off position; first circuit means for sensing operation of said on-off switch, and for generating a first alarm signal to indicate such operation and to identify the particular system being monitored in which said operation takes place; second circuit means for sensing a discontinuity in said security circuit loop, said second circuit means being adapted to generate a second alarm signal in response to a discontinuity in said security circuit loop when said on-off switch is in its on position, and thereupon to generate a third alarm signal when said on-off switch is operated to its off position, said second and third alarm signals identifying the particular system being monitored in which said discontinuity exists, and said second alarm signal being distinguishable from said first alarm signal; and transmitting means for coupling said first, second and third alarm signals to the alarm circuit loop.

2. An apparatus as defined in claim 1 in which said transmitting means includes a first alarm signal switch coupled to the alarm circuit loop, and in which said first circuit means includes a first code wheel for actuating said first alarm signal switch and a first motor for driving said first code wheel, and in which said oN-off switch includes means for energizing said first motor when said on-off switch is operated from on to off, said first circuit means further including first switch means for deenergizing said first motor when said first alarm signal has been generated and transmitted through said first alarm signal switch to the alarm circuit loop.

3. Apparatus as defined in claim 2 in which said first circuit means further includes first gear means coupled to said first code wheel for actuating said first switch means to deenergize said first motor when said first alarm signal has been generated and transmitted through said first alarm signal switch to the alarm circuit loop.

4. Apparatus as defined in claim 2 in which said on-off circuit loop includes means for energizing said first motor when said on-off switch is operated from off to on, with said first switch means deenergizing said first motor when said first alarm signal has been generated thereby and transmitted through said first alarm signal switch to said alarm circuit loop.

5. Apparatus as defined in claim 4 in which said first switch means include two switches in parallel with said first motor, one of which is closed by said on-off switch being operated from on to off, and the other of which is closed by said on-off switch being operated from off to on.

6. Apparatus as defined in claim 2 in which said transmitting means includes a second alarm signal switch coupled to the alarm circuit loop, and in which said second circuit means includes a second code wheel for actuating said second alarm signal switch, a second motor for driving said second code wheel, and means for energizing said second motor when said on-off switch is on and said discontinuity is sensed, said energizing means including second switch means for deenergizing said second motor when said second alarm signal has been generated and transmitted through said second alarm signal switch to the alarm circuit loop.

7. Apparatus as defined in claim 6 in which said second circuit means further includes second gear means coupled to said second code wheel for actuating said second switch means to deenergize said second motor when said second alarm signal has been generated and transmitted through said second alarm signal switch to the alarm circuit loop.

8. An apparatus as defined in claim 1 in which said second circuit means is adapted to generate a fourth alarm signal in the event the security circuit loop, once having been disrupted, is again closed while the on-off switch is still in its on position.

Images