FR2778260A1 - Data protection system - Google Patents

Abstract

The system has an integrated circuit having four Mercury switches and two jack plugs mounted in parallel, and offers the possibility to be connected to an existing alarm installed in the area to be protected. If computers or its jack plugs are removed by unauthorized persons, or ripped off, a sound alarm is given to alert security personnel.- DETAILED DESCRIPTION - A feed cable (22,23) is connected to an electrical network, by means of a sector block. An alarm circuit has a movement detector (1-4) in the form of mercury switches and a siren inside the computer. The two jack plugs (5,6) are mounted in parallel with the mercury switches and connected to a siren (16) via. a CMOS inverter (10) and a resistance (11)

Description

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Description

  DEVICE FOR PROTECTING COMPUTER EQUIPMENT AGAINST THEFT

  The invention relates to a device for protecting an electrical appliance against theft, for example a microcomputer or computer terminal and any other peripherals which can be merged on any medium. Ordinary anti-theft devices composed of a chain or a similar mechanical member are of course conceivable but have the disadvantages of being bulky and heavy if desired.

  effective, without providing sufficient security.

  The system is based on an integrated circuit which is associated with four mercury contacts I to 4 and 2 mono female jack plugs with 3.5 mm diameter inverters referenced 5 and 6 mounted in parallel, whose plug fitted with a grommet 17 opens global coverage of the IT environment.

  Figure I shows the electronic diagram.

  The functioning of the assembly installed inside the computer, so that at rest the contacts

1 to 4 are open.

  In this case the slightest movement moves the mercury and closes contacts 1 to 4 which immediately triggers the alarm. The loop 17 fixed on the jack plug 5 offers the possibility of connecting the computer to an alarm already

existing in the establishment.

  If the connection to this loop is broken or torn it will activate the sound signal via the buzzer 16 as well

  the local alarm which will notify the security service or the police station if it is linked to it.

  The start-up thanks to the switch 18, the capacitor 8 is charged with the contacts 1 to 4 mounted

  in parallel with the mono jack plugs with inverters 5 and 6 as well as the resistor 11.

  The movement of the computer (by an unauthorized third party) recorded by the contacts I to 4 or the disconnection of the jacks 5, 6 connected one or more peripherals will cause the emission of the sound signal thanks to the oscillator 14 mounted with a CMOS inverter and resistor 10 which controls

intermittently the buzzer 16.

  Once the alarm has been triggered, resting the computer, or reinserting the plug (s) in their supports 5 and 6 fixed on the bracket 25, means that even if the contacts are opened again the alarm will be

always on.

  It is after the capacitor 8 has emptied via the resistor 7 which prevents rapid discharge of the

  capacitor that the alarm is silent for about 20 s.

  The diode 15 prevents the capacitor 9 from discharging and causes a sudden stop of the oscillator.

  CMOS inverters 12 and 13 act as buffers between the oscillator and the trigger circuit.

  Figure 2 shows the electronic diagram of the power supply.

  The electricity source referenced 22, 23 is connected to the mains via a female chassis base 26 to a 9 volt power supply unit which in turn supplies a 9 volt double inverter relay 21 and a switch 18. The

  capacitor 24 and pin 14 of the integrated circuit which is at +.

  Pin 7 of the integrated circuit is connected to ground 22.

  However, as it is necessary to supply the protection system in the event of a mains failure, a backup battery 19 constituting an auxiliary source is also provided, the terminals are connected to the +

23 of the relay and to ground 22.

  When the coil 20 of the relay is energized, the contacts 21 move to the working position and cut the

battery 19.

  Figure 3 shows the square 25 (slot) to be inserted inside the computer is provided with 2 mono jack plugs with inverters 5, 6, used to connect the peripherals, as well as the possibility of

  resume the loop of an alarm already installed in the establishment.

  The base 26 receives the power plug from the power supply unit.

  FIG. 4 represents the front face comprising free covers o the key switch 18 is fixed.

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Claims (8)

Claims   1. Device for protecting computer equipment against theft provided with a power cable (22, 23) to an electrical network, by means of a power supply unit, comprising an alarm circuit (FIG. L) characterized in that it comprises at least one movement detector (there 4) in the form of contacts with   mercury and a siren (16) inside the computer.   2. Device for protecting computer equipment against theft according to claim 1 characterized in that it comprises 2 jack plugs (5 and 6) mounted in parallel with the mercury contacts (1 to 4) connected to the   + siren via the resistor (11).   3. Device for protecting computer equipment against theft according to claim I, characterized in that it comprises an integrated circuit with six inverting doors of which only three are used, therefore the doors (12 and 13) mounted in series serve as buffers, the diode (15) mounted in series with the door   (14) and the resistor (10) mounted in parallel goes to the - of the siren.   4. Device for protecting computer equipment against theft according to claim I, characterized in that it comprises two polarized capacitors (8 and 9), the two negative pins of which are grounded (22), the + of the capacitor (9) goes to the resistor (10) and to the anode of the diode (15). The resistance (7) has a   connection point at the + of the capacitor (8) and at the entrance of the door (12).   5. Device for protecting computer equipment against theft according to claim 1, characterized in   what it includes a loop (17) allowing the resumption of an existing alarm already in the room,   jack plug (5) 6. Device for protecting computer equipment against theft according to claim 1 characterized in that it comprises an auxiliary electrical supply including a battery (19) and a switching circuit (20, 21) for automatically supplying the card inserted in the computer in case of power grid failure.   7. A device for protecting computer equipment according to claim 1, characterized in that it comprises the power switching circuit consists of a relay (20) including an exciter coil   is connected to the + of the power cable.   8. Device for protecting computer equipment according to claim 1, characterized in that it comprises a switch (18) which goes to the pin (14) of the integrated circuit which is connected to the + via the   capacitor (24) whose output goes to the pin (7) of the integrated circuit which is connected to ground.