EP0559554B1 - Control system for device with autonomous blocks of sound alarm - Google Patents

Description

The invention relates to a control system, in particular for the dissemination of information, for an installation provided with autonomous sound alarm units, used to give the alert in the event of a fire.

The alarm in the event of a fire in installations is conventionally provided by sound, it involves means which are for example autonomous sound alarm blocks, as provided for by the French standard NFC 48-150 published by the union. Electricity technique.

These audible alarm blocks are designed to be able to be associated in parallel and possibly placed under the supervision of an alarm center.

In a first embodiment intended for installations without an alarm center, alarm blocks form an assembly connected to a loop comprising triggers, in particular of the glass breakage type, which have contacts opening the loop on which they are mounted. in series, in the event of actuation.

The blocks mounted in parallel include current detectors which control audible alarm means, when a loop opening interrupts the current which circulates continuously in the loop.

In another embodiment intended for alarm center installations, alarm blocks mounted in parallel form an assembly connected to a loop in the same manner as previously, and sound alarm means of the blocks are triggered in the event of '' interruption of the current which circulates permanently in the loop, the opening of the loop in the event of an alert is normally carried out using an opening contact controlled by the alarm center.

Each alarm block which is connected to an external power source which is most often a power distribution network is also connected to the loop wires which allow it to be controlled in the event of an alert.

Owing to their functionality, alarm systems of this type are intended to be permanently operational, even if in fact the actuation of the audible alarm means is normally only exceptional.

It is therefore conceivable to use the means offered by such operations for other uses from the moment when it is possible to give absolute priority to the alarm function, when an alert must be triggered.

In fact, the geographic arrangement of the audible alarm blocks in an installation which is designed to alert all the persons present likely to be concerned is also particularly well suited to the audible communication of synthetic indications which, for example , have a general interest or are intended for people who are mobile in the installation.

The invention therefore provides a control system, in particular for the dissemination of information, for an installation provided with associated sound fire alarm blocks according to a loop organization, in which the blocks of a loop are connected in parallel on both sides. 'other of at least one switching member placed in series in this loop which is supplied with electric current.

Each block includes a loop current detector connected to a management unit responsible for controlling electroacoustic means activated to generate an audible alarm signal, in the event of a loop current interruption of a duration greater than a threshold. According to a characteristic of the invention, the system comprises means associated with a loop switching member for generating pulses, on the loop, in the form of sequences corresponding to predetermined coded commands, each block comprising means, software or other and for example analog, to reconstitute the commands coded at the level of the management unit which it comprises from the variations created by the pulses on the loop as indicated by the associated loop current detector. The invention is defined by claims 1 and 4, its characteristics and advantages are specified in the description which follows in conjunction with the single figure mentioned below.

The single figure shows a block diagram of a control system for an installation fitted with audible alarm blocks.

The diagram shown in Figure 1 relates to an installation with sound alarm blocks referenced 1 grouped around a loop on which is mounted in series at least one switching device 2, of the opening contact type, of a trip device .

The trigger is for example with manual control, of the glass breakage type, as indicated above, it is possibly an electrically controlled trigger, the switching member 2 then being an electromagnetic relay or an electronic device, in each of the case it comprises at least two switching terminals A and B which are electrically connected when the member is in a first normal standby state, here symbolized by a relay contact closed at rest, and which are capable of being electrically isolated l 'of each other if the organ is placed in another state.

This member is placed in series in a loop which is supplied with current by a generator, such as 3, and which closes at a current detector, such as 4, responsible for signaling any interruption of the current flowing through the loop.

A loop can of course comprise several switching members arranged in series along the loop and usually distributed in the installation to allow triggering from then different locations, in the case of an installation with manual alert triggering, any opening of the loop by one of the members ensuring of course the interruption of the loop current.

Several alarm blocks 1 are also capable of being served by the same loop from the moment they are connected in parallel to the two terminals A and B of the same switching device, as shown in the single figure, or to the corresponding end terminals of a set of switching members in series on the same loop, in particular in the case of a multi-trip installation.

Usually each alarm unit 1 comprises a circuit 5 for supplying electrical energy intended to be connected to an external source which is most often an AC distribution network.

For security reasons, an alarm unit also includes an internal energy source 6, usually of the storage battery type, in order to allow autonomous operation of the unit and in particular of the audible alarm means 7, in the event of network supply interruption.

The circuit 5 and the internal source 6 are connected by a diode assembly 8, known, so as to be able to replace one another to supply the alarm block 1 of which they are part and the generator 3 loop current, without, in particular, significant interruption of this current.

A charger 9 allows charging and maintaining the charge of the internal source 6, when this source is of the storage battery type.

A management unit 10 is also incorporated in each block, it is for example organized, in a known manner, around a microcontroller 10M equipped with read only and / or random access memories not shown, as well as a time base 10B in order to '' control the audible alarm means 7 and auxiliary means 12, such as signaling means capable of providing information, in particular on the state of the block and of the loop to which this block is connected, for example using indicators or a screen display.

The auxiliary means 12 are often arranged to allow the control of one or more simple actuators, not shown, via the management unit 10.

The latter is therefore connected by its input-output ports to the current detector 4 which provides it with information on the state of the loop to which the block is connected, to the internal source 6 and here to the charger 9 which respectively provide indications on the respective supply possibilities of the block by this source and by the network.

It is also connected at least by control outputs to the auxiliary means 12 mentioned above and to the sound alarm means which preferably include an electro-acoustic transducer 7 usually attacked via an electronic assembly 13.

The time base 10B of the management unit makes it possible in particular to fix a certain number of time delays, for example of alert stop after triggering.

According to the invention, the time base 10B of a block is also used in connection with the microcontroller 10M and with the loop current detector 4 of this block to decode commands produced in impulse form for example at or one of the switching members 2 in series with a loop.

The memories of the microprocessor 10M then contain software modules making it possible to reconstruct the coded commands from the indications received from the associated detector and to trigger the corresponding actions.

A device 14 generating coded commands is then associated with the switching member 2 chosen, for example a generator of command pulses
which is clocked by a time base not shown and which acts on the switching member so that it produce variations in the loop current chosen to be detectable by the current detectors of the blocks served by a loop, without risking being taken into account as a loop break involving an alarm triggering.

In a simple embodiment, the device 14 is programmed to act on a switching member 2 of a loop so as to trigger loop openings of which the limited duration is sufficient for these openings to be taken into account by the detectors 4 connected to the loop, the microcontroller 10M associated with a detector in a block being programmed, in a manner known per se, to recognize with the assistance of the time base 10B of this block, if a loop opening is of a duration greater than an alert triggering threshold or if shorter it is likely to correspond to an element of a message corresponding to a predetermined coded command.

It is then possible to transmit different coded commands from a device 14 associated with a switching member 2 to the blocks connected to the loop in which this switching member is inserted, each command being for example coded by a given number of breaks. successive loops of the same fixed duration in a determined period of time.

The control unit of each of the blocks receiving a message corresponding to one or one of the coded commands provided, by means of a loop, then counts the number of openings which are signaled to it by the detector 4 associated with it and interprets this count so as to trigger a corresponding, predetermined action.

This action is likely to be a warning bell at the start or end of the course in the case of an installation carried out in a school establishment, many other actions can be initiated in the same way, such as the emission a predetermined message intended for all or part of the people located within sound range of an electroacoustic transducer 7, the message being for example recorded in digital form in a memory provided in the management unit 10, the latter then being provided with a digital decoder - analog inserted in or upstream of the electronic assembly 13

A self-test function can also be triggered at the level of each block in order to facilitate the supervision and consequently the maintenance of the installation which comprises such blocks.

According to an alternative embodiment, the device 14 is a circuit capable of significantly and for a determined time modifying the value of the current passing through the switching member 2 with which it is associated so as to produce variations, for example clocked in a predetermined manner, loop current without interrupting it.

The blocks 1 served by the loop, on which this device 14 and the associated switching member act, then comprise detectors 4 arranged in a manner known per se, to take into account on the one hand the loop current interruptions, d 'on the other hand the variations of loop current of predetermined value (s), the choice of actions between triggering of alert and one or the other of the specified actions being carried out by the microcontroller 10M of the unit of management of each block as a function of its programming and in connection with the associated time base 10B, the command and triggering of the alert being given priority.

Claims (4)

1. A control system for an installation provided with fire sound alarm units (1) associated together by means of a loop organization, the units in any one loop being connected together in parallel on either side of at least one switching member (2) placed in series in the loop, provision being made to feed the loop with electrical current, each unit including a loop current detector (4) connected to a controller (10) assigned to controlling electroacoustic means (7) activated to generate a sound alarm signal in the event that the loop current is interrupted for a duration greater than a predetermined threshold, said control system being characterized in that it includes means (14) associated with a loop switching member for generating pulses, on the loop, in the form of sequences corresponding to predetermined encoded commands, each unit including means in the controller (10) thereof for reconstituting the encoded commands on the basis of the variations created by the pulses on the loop as indicated by the associated loop current detector.
2. A control system according to claim 1, characterized in that the means (14) for generating pulses on a loop trigger short breaks in the loop by means of the switching member (2) with which they are associated.
3. A control system according to claim 1, characterized in that the means (14) for generating pulses on a loop cause variations in the loop current.
4. A sound alarm unit for a control system according to claim 1, characterized in that it includes means for firstly reconstituting encoded commands at the controller (10) included in it on the basis of the variations created by the pulses on the loop as indicated by the loop current detector incorporated in it, and secondly triggering the corresponding action.

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