Classifications

• • G—PHYSICS
  • G08—SIGNALLING
  • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
  • G08B29/00—Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
  • G08B29/02—Monitoring continuously signalling or alarm systems
  • G08B29/04—Monitoring of the detection circuits
  • G08B29/046—Monitoring of the detection circuits prevention of tampering with detection circuits
• • G—PHYSICS
  • G08—SIGNALLING
  • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
  • G08B13/00—Burglar, theft or intruder alarms
  • G08B13/22—Electrical actuation
• • G—PHYSICS
  • G08—SIGNALLING
  • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
  • G08B29/00—Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
  • G08B29/02—Monitoring continuously signalling or alarm systems
  • G08B29/04—Monitoring of the detection circuits

Definitions

• the present invention relates to an electronic alarm, security, control or surveillance device comprising self-protection and dynamic self-control circuits intended to detect any faults, breakdowns or sabotages liable to render inoperative the device or installation.
• the device according to the invention comprises two parts: a module A (FIG. 1) controlled by the detection and self-protection loops and a module B (FIG. 2) which receives and controls the information coming from the previous one and which activates the various devices intended to signal possible malfunctions and to produce the various actions necessary in the event of an alarm: triggering of sirens, lighting switching on, activation of cameras. . . the output c of module A is connected to the input d of module B, either directly or by any wireless connection method.
• Detection.- Detectors Dr, Dr '... each comprising a resistor in series with contacts are placed in series in a detection loop, constituting with P 2, R 9, R 8 and R 7 a balanced bridge around point a.
• IC 2 and IC 3 mounted as threshold detectors, one positive and the other negative, cause the bridge to become unbalanced with a low voltage state at point b which establishes a positive voltage on output 3 of IC 4 for one duration limited to about one second by the set R 13 - C 11 playing the timer role.
• the alarm will be triggered and locked for two to three minutes using IC 6 (fig.2).
• the detection loop can be formed from I to 10 detectors each comprising a resistance of 3.3 kilohms; the resistor R 9 (of 33 kilohms) can itself be replaced by 1 to 10 detectors of 3.3 kilohms (plus an adjustable resistor).
• a light-emitting diode L 1 makes it possible to control the balance of the bridge by means of P 2 (short-circuited R 13 - C 11 for the duration of the adjustment).
• IC 1 is mounted as a square signal generator with frequency f, for example equal to 15 Hz.
• R 8 3.3 kilohms
• T 2 made conductive through C 2
• R 7 also 3.3 kilohms
• T 1 is added to the total resistance of the bridge due to the momentary blocking of T 1 through C 3-
• IC 2 and IC 3 the appearance at point c of rectangular signals of frequency 2 f, in this case 30 Hz.
• These self-controlled signals are picked up by C 19 on output 3 of IC 6 (point f), that is to say practically at the terminals of the alarm relay REL 1, and applied by means of T 3 to the frequency control circuit formed by IC 7 and IC 8.
• the operating light L 3 goes out and the REL 2 relay activates the audible fault warning.
• REL 1 is timed by C 17 to prevent the self-checking signals from triggering the alarm.
• the self-controlled signals are transmitted directly to IC 7 (from g) and indicate, thanks to L 3 and the buzzer, the maintenance or disappearance of the cause of the alarm, c that is, whether the bridge imbalance persists or not.
• the same self-monitoring system can be used by placing the detectors (with a resistor) in a Wheatstone bridge.
• the same process can be applied in the case of a detection loop whose total resistance is measured and stored in memory by a microprocessor, any variation of a certain importance of the value stored causing a change of state to the output of the circuit.
• the signal generator IC 1 is controlled by a self-protection loop in which are placed (in series) the microswitches (Sw, Sw '...) protecting the various elements of the installation, closed by the capacitor C 1.
• the cut or short-circuit of the self-protection loop causes the 15 Hz oscillations to disappear. These signals are applied by D 3 and C 12, after phase shift by R 17, C 13 and R 16, at the entry (2-6) of IC 4 and are found in the form of short pulses at point c. These pulses at 15 Hz are controlled by IC 9, and their absence causes the ignition of L 4 and the triggering of the fault horn.
• the self-protection loop can usefully double the supply and detection lines and, in general, the conductors connecting the different parts of the installation.
• An on / off contactor (K1-K2-K3) enables the alarm to be put out of standby and to neutralize the self-monitoring system, the self-protection system remaining only active; it can be used to instantly interrupt the alarm siren.
• the self-monitoring and self-protection system is particularly suitable for a wireless link between the various elements of the installation.
• R 1 0.5 megohm
• R 2 10 kilohms
• R 3 47 kilohms
• R 4 0.47 megohm
• R 5 10 kilohms
• R 6 0.47 megohm
• R 7, R 8 3.3 kilohms
• R 9 33 kilohms
• R 12 0.1 megohm
• R 13 1 megohm
• R 14 0.47 megohm
• R 16 1 megohm
• R 17 0.22 megohm
• R 18 10 kilohms
• R 19 560 ohms
• R 23 1 megohm
• R 24 6.8 megohms
• R 25 1.5 megohm
• R 26 560 ohms
• R 27 10
• the present invention is not limited to the single embodiment described above by way of example, but also applies to all the variants and other embodiments implementing the same methods, in particular by using different components or microprocessors.
• the device which is the subject of the invention makes it possible to make the operation of the apparatus and of the alarm, surveillance, security, control, measurement, etc. operations very secure, by warning of breakdowns, faults, incidents, sabotage. , etc., which could render these devices inoperative.
• This device specially designed for the protection of goods and premises against theft and intrusion, can also be used for fire detection and prevention. It can also be adapted to various other uses, in particular in industry, for medical surveillance, etc.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Computer Security & Cryptography (AREA)
• Alarm Systems (AREA)

Priority Applications (2)

Applications Claiming Priority (1)

Publications (1)

Family

ID=9278071

Family Applications (1)

Country Status (4)

Families Citing this family (1)

Citations (4)

• 1982
  • 1982-10-06 FR FR8216842A patent/FR2534396B1/fr not_active Expired
• 1983
  • 1983-09-29 EP EP19830902995 patent/EP0121521B1/de not_active Expired
  • 1983-09-29 DE DE8383902995T patent/DE3376702D1/de not_active Expired
  • 1983-09-29 WO PCT/FR1983/000194 patent/WO1984001456A1/fr active IP Right Grant

Patent Citations (4)

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