US3858194A

US3858194A - Security system with means for subscriber control

Info

Publication number: US3858194A
Application number: US00403415A
Authority: US
Inventors: L Jedynak; P Bert
Original assignee: Oak Industries Inc
Current assignee: OCI Communcations Inc
Priority date: 1971-03-22
Filing date: 1973-10-04
Publication date: 1974-12-31
Anticipated expiration: 1991-12-31

Abstract

Alarm signals are processed in a security system in which an onsite detector is connected by a communications link to a central station. A time delay circuit is connected at the site being protected, to the detector, with the time delay means being turned on and off by a time clock. The time delay period permits the alarm system to be activated and deactivated by predetermined procedures to prevent the central station from receiving unnecessary alarm signals.

Description

United States Patent 1191 Jedynak et al.

1451 Dec. 31, 1974 SECURITY- SYSTEM WITH MEANS FOR SUBSCRIBER CONTROL Inventors: Leo Jedynak, Madison, Wis.; Paul A. Bert, Crystal Lake, [11.

Assignee:

Filed: Oct. 4, 1973 App]. No.: 403,415

Related U.S. Application Data Continuation-impart of Ser. No; 304,143, Nov. 6, 1972, which is a continuation-in-part of Ser. No. 126,590, March 22, 1971.

U.S. Cl 340/276, 340/274, 340/309.1 Int. Cl. G08b 13/00 Field of Search 340/276, 274, 309.1

References Cited UNITED STATES PATENTS 9/1969 Corbell 340/274 Oak Industries, Inc., Crystal Lake, I 111.

Peterson 340/276 Fogiel 340/274 Primary Examiner-Glen R. Swann, lll Alrorney, Agent, or FirmKinzer, Plyer, Dorn & McEachran 5 7 ABSTRACT Alarm signals are processed in a security system in which an on-site detector is connected by a communications link to a central station. A time delay circuit is connected at the site being protected, to the detector, with the time delay means being turned on and off by a time clock. The time delay period permits the alarm system to be activated and deactivated by predetermined procedures to prevent the central station from receiving unnecessary alarm signals.

5 Claims, 1 Drawing Figure SECURITY SYSTEM WITH MEANS FOR SUBSCRIBER CONTROL CROSS REFERENCES TO RELATED APPLICATIONS This application is a continuation-in-part of copending application Ser. No. 304,143 filed Nov. 6, 1972,

which was a continuation-in-part of copending application Ser. No. 126,590, filed Mar. 22, 1971.

SUMMARY OF THE INVENTION This invention relates to a method of processing alarm signals in a security system and has for a primary purpose a security system in which the alarm signals normally associated with opening and closing are processed at the site being protected rather than at the central station.

Another purpose is a security system using a time clock controlled time delay means between the detection device and the central station connected thereto.

Another purpose is a security system in which one or more of a plurality of detection means located at the premises to be protected is controlled by a time clock and a time delay circuit to process normal opening and closing signals.

Another purpose is a method of on-site processing of alarm signals.

Other purposes will appear in the ensuing specification, drawings and claims.

BRIEF DESCRIPTION OF THE DRAWING The invention is illustrated diagrammatically in the attached illustration of an alarm system.

DESCRIPTION OF THE PREFERRED EMBODIMENT One of the primary problems of burglar alarm or security systems in which an alarm is transmitted to a central station, whether it be a police station or a private alarm station, is a normally high number of alarm signals which result from authorized entry and exit.

Prior art involving security systems treat any alarm signal during the nighttime hours as an actual alarm and react accordingly. During the morning hours, when the installation is being opened by the subscriber, the alarm signals received at the central station are noted for compatibility with the prearranged opening schedules of that particular installation and then recorded in a log book without further action. If the signals received do not agree with the prearranged opening interval or time window, for example an hourand-a-half; say from 6:30 A.M. to 8:00 A.M., then the received signal at the central station is interpreted as an alarm. If the alarm signal (during the opening hours) persists for a long interval, a further check is normally made by the central station to determine whether a real alarm exists or whether the subscriber has merely neglected to deactivate his alarm system. Similarly, the alarm system is normally reactivated prior to the prearranged closing time and if proper closing sequences are followed, the alarm signals received by the central station will be recorded in a log book without further action.

The present invention is an improvement over the prior art by simplifying the routine of the central station and to a large extent eliminating the burden of processing the normal opening and closing alarm signals.

In operation of the system disclosed herein during the normal closed hours of the subscriber, the system is in its normal alarm mode. That is, all signals are transmitted without delay to the central station and are treated as legitimate alarms. During the start of business, a time of day clock sets the alarm system to a normal entry mode of operation. The normal entry mode provides a time window bracketing the normal start of business of approximately one and one-half hours so that the installation may be entered during this time interval and the alarm signal associated with this entry delayed approximately one and one-half minutes or long enough for the subscriber to control or interrupt the alarm signal to the central station. Hence, alarm signals at the central station associated with normal authorized entry of the protected premises are eliminated, thus greatly reducing the alarm signal traffic at the central station during the start of the business day. The subscriber control may be, but should not be, limited to a key switch that interrupts the alarm signal caused by entry through normal entry routes of the installation, and simultaneously sets the system so that normal business may be conducted through these routes without alarm until the normal close of business. If there is no entry during the normal entry period, such as holidays and weekends, the alarm system will revert to the normal alarm mode until the next normal entry period scheduled approximately 24 hours later. After entry and subscriber controlled alarm signal interruption, a time of day clock sets the system to a normal exit mode corresponding to the close of business. At the normal time for close of business, the time of day clock may, if desired, provide a time window of approximately one and one-half hours bracketing the normal close of business or exit period.

The normal exit mode allows authorized personnel of the subscriber to lock up and secure the installation by subscriber control and provide a time delay of the alarm signals for the normal exit routes so that an authorized person may exit without causing an alarm to be reported to the central station during the period of the intentional time delay. After the time delay of approximately one and one-half minutes, or long enough for a person to secure the system and exit the installation using a predetermined sequence of actions, the system reverts to the normal alarm mode. The normal alarm mode communicates to the central station all alarms without any intentional time delay. Failure to follow the predetermined sequence causes an alarm to be sent to the central station. Thus, the normal exit mode eliminates the numerous alarm signals associated with normal exit from the secured premises.

The system automatically reverts to the normal alarm mode if the installation is locked up or secured" by subscriber control before the normal exit period. Further, if the system is not secured during the normal exit time interval, the system reverts to the normal alarm mode and an alarm signal is sent to the central station at the end of the normal exit interval indicating that the installation has not been secured in an authorized manner.

A test mode is included so that the system may be tested at the option of the central station or locally by the subscriber. Further, the time of day clock may beset for accuracy by the central station or locally by the subscriber. Also, a reset signal may be sent by the central station to place the system in the normal alarm mode, if desired.

Turning to the drawing, a door sensor is indicated at with block 12 diagrammatically representing the remaining sensors that may be included in the premises to be protected. The central station is indicated diagrammatically at 14 with the communication system or communications link between the central station and the subscriber being indicated at 16. An output alarm gate 18 is connected through the communication system 16 to the central station 14. The alarm gate 18 may have four inputs, one of which is directly connected by line 20 to the sensors represented by block 12. Thus, normal alarms instituted other than by opening and closing of the exit door, will be transmitted directly to the central station.

The door sensor 10 is connected to a master clock 22 and to the master control unit and sequence monitor 24 by lines 26 and 28 respectively. The door sensor 10 is also directly connected to a normal alarm AND gate 30 by line 32, with gate 30 being connected by a line 34 to the output alarm gate 18.

The master clock 22 includes normally open switches 36 and 38 which are automatically closed by a clock mechanism during the opening window which, as indicated above, may be 1% hours in duration. The master clock also includes a normally open switch 40 controlled by the clock mechanism and connected to a positive source of voltage for providing a momentary signal at the end of the exit period to the master control unit, as described hereinafter.

Master clock switch 38 is connected by a line 42 to an entry delay 44 which may provide a delay of 1% minutes for deactivation of the alarm system. The entry delay 44 is connected through entry alarm gate 46 and line 48 to the output alarm gate 18.

The master control unit 24 includes a main power switch 50 connected to a source of voltage and in parallel with contacts 52 of a relay coil which is indicated at 54. A monostable flip-flop of conventional design, indicated at 56, is connected to one side of switch 50, with the flip-flop 56 in turn being connected to a two-bit shift register 58. A shift pulse generator 60 receives its triggering pulse via line 28 from the door sensor 10. The output from the shift register 58 is connected to an exit OR gate 62, which has a second input indicated at 64 which represents other exit sequence requirements. For example, there may be certain requirements such as the insertion of a magnetic address card, a pair of keys rather than a single key, all of which functions must be satisfied, in sequence, in order to provide an appropriate exit from the premises.

OR gate 62 is connected through an inverter amplifier 66 to a normal entry control AND gate 68. The output from gate 68 is connected by a line 70 to AND gate 30. The other input signal for AND gate 68 is passed via line 72 from the closure of switch 36 of the master clock 22.

OR gate 62, in addition to being connected to inverter amplifier 66, is connected to exit AND gate 74 which is connected by line 76 to exit alarm gate 78. Exit AND gate 74 is also connected to switch 50 and relay contacts 52.

An exit delay 80, which is connected to AND gate 78, is also connected by line 82 to switch 50. Switch closure or the operation of relay 54 provides a signal to be supplied to the" exit delay as described hereinafter.

A signal from closure of switch 50 is also supplied to entry sequence OR gate 84, which has a second input, designated 86, representing other entry sequence requirements. Such requirements, as described above, may be the insertion of a magnetic address card, the use of a plurality of keys in a certain pattern, or other similar entry sequence requirements. The output from OR gate 84 is connected by line 88 to the entry alarm AND gate 46.

A failure-to-exit AND gate is indicated at 90 and has one input connected through inverter amplifier 91 to switch 50 and a second input connected via line 92 to switch 40 in the master clock 22. The output of the failure-to-exit AND gate 90 is connected by line 93 and a monostable flip-flop 94 to relay coil 54 and to normally open contacts 96 controlled by relay 54. Normally closed reset contacts 98 are connected to a positive source of voltage and to contacts 96.

As described above, the system has an opening or entry sequence, a normal exit sequence and an operating sequence that takes place if the normal exit sequence is not followed at the appropriate time. During the time that the premises are closed, the system permits all alarm signals from the alarm sensors to be transmitted without delay to the central station. An alarm signal from the entry doorway sensor 10 is transmitted by line 32 to gate 30, subsequently through line 34 to gate 18, where the signal is placed on the communication line to the central station. Alarm signals from the fire sensor or other protection sensors will be transmitted on line 20 to gate 18 and subsequently to the central station.

At a prescribed time in the morning, the master clock initiates the normal opening window. Switches 36 and 38 move to a closed position. The closure of switch 36 is signaled to the master controller via line 72 which signal, through gate 68 and line 70, inhibits gate 30. Thus, any door sensor alarm signal will not be transmitted directly to gate 18. After closure of switch 38, a door opening alarm signal from sensor 10 causes a signal to pass through line 42, to the entry delay 44. The delay period provided is sufficient for the alarm to be deactivated. The opening of main power switch 50 removes the voltage signal applied to gate 46 through OR gate 84, placing an inhibit signal on gate 46, to prevent the transmission of the alarm signal to the central station. Thus, during the entry delay period the subscriber must go to the master control unit and open switch 50 and perform prescribed additional shutdown procedures in order to place an inhibit signal on AND gate 46. If it is a holiday, and no entry is to take place, then at the end of the opening window, the master clock returns to the position shown, with switches 36 and 38 in their normally open position. Thus, any door alarm signals will be transmitted directly through gate 30 and gate 18 to the central station.

In a normal exit sequence, when the subscriber is ready to leave, he first closes the main power switch 50, applying a turnon voltage to all sensors. Such a switch closure also applies a signal to the monostable flip-flop 56 which presets the shift register 58 to an all ones condition. When the subscriber leaves the premises, the opening and closing of the exit door causes an alarm signal from sensor 10, triggering pulse generator 60 to change the condition of shift register 58 and pass a logical zero signal through the shift register to OR gate 62. This signal, along with any other sequence requirements which may be placed on the subscriber, generates a signal for gate 74, which in turn inhibits gate 78, to prevent the delayed exit alarm generated by the initial closure of the power switch 50 from being transmitted to the central station. Such a power switch closure would normally send an alarm signal to the central station via exit delay 80 and gate 78 if gate 78 were not inhibited, as described above.

Simultaneously with inhibiting the transmission of the delayed exit alarm, the signal from OR gate 62 is used, via gate 68, to immediately enable the normal door alarm gate 30 of the system so that any subsequent opening of the entrance door will result in an immediate transmission of an alarm signal to the central station.

Thus, the closure of the main power switch 50 by the subscriber will first cause a signal to be transmitted to the exit delay 80. An alarm signal from sensor caused by opening of the exit door within the exit delay period will provide a signal through OR gate 62 and AND gate 74 to AND gate 78 to inhibit the transmission of the delayed exit signal. Such an alarm signal will also activate the alarm system by removing the inhibit on gate 30.

In addition to the normal exit sequence procedures, means are provided to accommodate a failure on the part of the subscriber to activate the alarm system at the appropriate time. If the subscriber fails to exit by the specified deadline, as determined by the setting of the master clock, switch 40 of the master clock will close and provide a signal via line 92 to gate 90. If the system has not previously been turned on by closure of switch 50, which closure would be signaled via the inverter amplifier 91 to inhibit gate 90, a signal will be generated on line 93 via monostable flip-flop 94 to operate the failure to exit relay 54. When relay 54 operates, normally open contacts 96 will close, locking the relay in the on" condition until the subscriber or central station personnel operate the reset switch represented by normally closed contacts 98. Upon operation of relay 54, contacts 52 close and power is immediately supplied to the alarmsensors. Such an application of power initiates an exit alarm on line 82 to the exit delay 80 and through the exit delay 80 to gate 78. Since there will be no signal from the door sensor 10, indicating that the subscriber has passed through the door, the shift pulse generator 60 will not provide a signal to the shift register 58 and thus OR gate 62, through AND gate 74, will not prevent the transmission of the delayed exit signal to the central station. The central station is accordingly advised that the normal exit procedures have not been followed. However, the alarm system will have been activated.

In summary, procedures are provided whereby the subscriber may enter the premises during the normal opening window and deactivate the alarm system. The subscriber has a predetermined delay period during the opening window as controlled by the master clock to effect system shutdown. When the subscriber desires to leave the premises, he must execute a certain exit sequence and this must be done at a prescribed time period. When the subscriber leaves after system turn-on, he has a predetermined delay period, determined by the exit delay 80, to exit the premises. Thus, any opening and closing of the door during that period will not cause an alarm to be sent to the central station. If, however, the subscriber either does not exit during the delay period or fails to turn on the alarm system at the prescribed time, an alarm will be transmitted to the central station, indicating that the normal exit procedures have not been followed.

Whereas the preferred form of the invention has been shown and described herein, it should be realized that there may be many modifications, substitutions and alterations thereto.

We claim:

1. A security alarm system including detection means located at an installation to be protected, a central station, a communications link between said detection means and central station, a plurality of time delay means at the installation to be protected connected in circuit between said detection means and central station, each of said time delay means being arranged for use during a different period of the day, said time delay means preventing transmission of an alarm signal from said detection means to said central station for a predetermined period after initiation thereof, and a time clock, at the installation to be protected, for controlling operation of said time delay means.

2. The alarm system of claim 1 further characterized by and including a plurality of detection means located at the installation, with said time delay means being connected between at least one of the detection means and the central station.

3. The alarm system of claim 1 further characterized in that said time clock provides for operation of said time delay means at two predetermined time intervals during the normal business day.

4. The alarm system of claim 1 further characterized by and including on-off switch means connected between said detection means and said transmission circuit.

5. The alarm system of claim 1 further characterized by and including a bypass connected between said detection means and said time clock, bypassing said time delay means.