Vault alarm system and method

Claim 2

In an alarm system for protecting an enclosed space such as a bank vault against disturbances such as burglary and fire, sensing means for detecting a disturbance and producing a pulsating disturbance signal in response thereto, first counting means connected for receiving the signal from said sensing means and counting the number of pulses in said signal, means responsive to the disturbance signal for resetting said counting means in the event that the disturbance is longer than a predetermined minimum duration, additional counting means for counting the number of times the number of pulses exceeds a predetermined number in a predetermined time and means for actuating said alarm means when said number of times exceeds a predetermined number.

Claim 3

An alarm system as in claim 1 wherein all of said system except said sensing means is mounted in a tamper-proof box and wherein said sensing means is connected to the remainder of said system by means of a tamper-proof cable.

Claim 4

An alarm system as in claim 1 together with power supply means for supplying operating power to said system from a conventional alternating current source and battery means for supplying the operating power upon interruption of the power from said supply means.

Claim 5

An alarm system as in claim 1 together with ion detector means for sensing smoke and fire and means connecting said ion detecting means intermediate said additional counting means and said alarm means for energizing said alarm means in response to smoke and fire.

Claim 6

An alarm system as in claim 4 wherein said ion detector means includes an ion detector, a power supply adapted for supplying an operating voltage at one level to said ion detector during normal conditions and for supplying an operating voltage at a different level when smoke and fire are sensed, and level detector means connected to said ion detector for detecting the level of the voltage supplied to said ion detector.

Claim 7

In a vault alarm system, an input terminal adapted for connection to a sensing device for receiving a pulsating signal caused by a disturbance detected by the sensing device, first pulse counting means connected for receiving the signal from said input terminal and producing a first step ramp signal having a magnitude corresponding to the number of pulses in the received signal, first level detector means connected to the output of said first pulse counting means and adapted for firing when the magnitude of said first step ramp signal reaches a predetermined level, means responsive to the signal produced by a disturbance for resetting the first pulse counting means and level detector means in the eveNt that the disturbance is longer than a predetermined minimum duration, second pulse counting means responsive to the output of said first level detector means for producing a second step ramp signal having a magnitude corresponding to the number of times said first level detector means fires in a predetermined period of time, second level detector means connected to the output of said second pulse counting means and adapted for firing when the magnitude of said second step ramp signal reaches a predetermined level, and means connected to said second level detector means for actuating an alarm in response to the firing of said detector means.

Claim 8

In a vault alarm system, an input terminal adapted for connection to a sensing device for receiving a pulsating signal caused by a disturbance detected by the sensing device, first pulse counting means connected for receiving the signal from said input terminal and producing a first step ramp signal having a magnitude corresponding to the number of pulses in the received signal, first level detector means connected to the output of said first pulse counting means and adapted for firing when the magnitude of said first step ramp signal reaches a predetermined level, means responsive to the signal produced by a disturbance for resetting the first pulse counting means and level detector means in the eveNt that the disturbance is longer than a predetermined minimum duration, second pulse counting means responsive to the output of said first level detector means for producing a second step ramp signal having a magnitude corresponding to the number of times said first level detector means fires in a predetermined period of time, second level detector means connected to the output of said second pulse counting means and adapted for firing when the magnitude of said second step ramp signal reaches a predetermined level, and means connected to said second level detector means for actuating an alarm in response to the firing of said detector means.

Claim 9

An alarm system as in claim 6 together with a one-shot multivibrator connected intermediate the output of said first level detector means and the input of said second pulse counting means, said multivibrator being triggered by the firing of said first level detector means and producing a pulse of predetermined magnitude and duration in response thereto.

Claim 10

An alarm system as in claim 7 wherein said second pulse counting means includes a capacitor across which said second step ramp signal is produced and means for selectively connecting a resistive element across said capacitor to discharge the same at a desired rate to determine the period of time in which successive firings of said first level detector means and said multivibrator must occur to produce a signal of sufficient magnitude to cause firing of said second level detector means and actuation of the alarm.

Claim 11

In a method for protecting an enclosed space such as in alarm against disturbances such as intruders the steps of receiving a pulsating signal indicative of a disturbance, counting the number of pulses in the received signal to distinguish signals due to intruders and fires from signals due to other disturbances, restarting the counting of pulses in the received signal in the event that the disturbance is longer than a predetermined minimum duration, counting the number of times the number of pulses reaches a predetermined count, and actuating an alarm when the number of times counted reaches a predetermined number.

Claim 12

In a method for protecting an enclosed space such as in alarm against disturbances such as intruders the steps of receiving a pulsating signal indicative of a disturbance, counting the number of pulses in the received signal to distinguish signals due to intruders and fires from signals due to other disturbances, restarting the counting of pulses in the received signal in the event that the disturbance is longer than a predetermined minimum duration, counting the number of times the number of pulses reaches a predetermined count, and actuating an alarm when the number of times counted reaches a predetermined number.