GB2233136A - Method for operating a fire extinguisher system - Google Patents

Abstract

Triggering of the operation of the extinguishing system is effected after a delay, in response to detection, eg by a microphone 16, 17, of a detectable alarm signal emitted by an alarm emitter 14, 15. A control unit 10, 11 is operative to cause energization of the alarm emitter in response to operation of fire alarms 8. The control unit is also responsive to a signal from the microphone to send a signal to cause delayed triggering of the extinguishing system. <IMAGE>

Description

KETHOD FOR OPERATING A FIRE EXTINGUISHER SYSTEM This invention relates to

a method for operating a control system for fire extinguishers protected against electromagnetic disturbing influence (e.g. strokes of lightning), in which, in the case of fire, high-speed opening devices of one or more extinguishing agent containers are controlled, after expiration of an early warning time, by an extinguishing control device and the extinguishing agent (for example C02, Halon or the 10 like) stored in the extinguishing agent containers is released. Such fire extinguishers are used in particular for the protection of rooms and objects e.g. for EDPunits, computing centres, connecting and control central 15 points and the like. These fire extinguishers consist substantially of a fire alarm system with a fire alarm control system, a battery of bottle cells formed by several high-pressure bottles for carrying the gaseous extinguishing agent, the tube system with nozzles for 20 delivering the extinguishing agent, a collecting pipe connecting each individual high-pressure bottle of the battery of bottle cells to the extinguishing line and a high-speed opening valve associated with each bottle for releasing the extinguishing agent. 25 With gas extinguishers which, because of the nature of the extinguishing agent, present a danger for life and limb for people who are present in the room which is to be protected, legislation demands that before flooding the room an evacuation alarm is given 30 in order to draw attention to the in-flowing extinguishing agent and to direct people to leave the room. There is a requirement that an extinguishing gas may not under any circumstances be administered without a preceding evacuation alarm. In order to achieve almost absolute safety the electric time control circuits used hitherto would have to be replaced by expensive mechanical delay devices. At least one warning signal is generated pneumatically or mechanically with such extinguishing control systems and also the release of the extinguishing agent is achieved pneumatically after expiration of the delay time.

In particular with electrical control of a highspeed opening valve on the extinguisher there is the danger that, for example, with a stroke of lightning the high-speed opening valve is opened without an alarm being triggered before.

The purpose of the present invention is to create a control system for an extinguisher, which with electrical control is protected against electromagnetic disturbing influence e.g. strokes of lightning - and fully monitored at the same time.

Thus according to the present invention, there is provided a method for operating a control for fire extinguishers protected against an electromagnetic disturbing influence, in which, in the event of fire, high-speed opening devices of one or more extinguishing agent containers are controlled, after expiration of a early warning time, by an extinguishing control device and the extinguishing agent is released, wherein a signal is emitted by the extinguishing control device to an alarm emitter to trigger emission of a detectable alarm by the alarm emitter and wherein an associated sensor detects the detectable alarm and discharges a release signal to the extinguishing control device, only with ordered operation of the alarm emitter, and the release signal enables the sequence of a time control circuit and the time control circuit controls a control unit for an electric-motor driven release device firstly after expiration of a set early warning time, wherein operation of the control unit is also possible only with application of the release signal and the release device effects, after expiration of a mechanically produced safety time, the release of the extinguishing agent. 5 The detectable alarm may be an acoustic alarm or an optical alarm, or both. There may be more than one alarm emitter and more than one sensor. With this method, even with a stroke of lightning to a fire extinguisher, triggering of the extinguisher without previous release of an alarm is prevented with certainty. A direct influence of the motor of the extinguisher release device by a current flow induced by lightning can only occur over the duration of the lighting strike. This time duration is, however, smaller than the safety time provided according to the invention. If because of a stroke of lightning, or for other reasons, no alarm can occur, then no release signal from the sensor is generated so that neither the time control circuit nor, before expiration of the warning time, the control of the motor-driven release device. can be controlled.

According to another aspect of the present invention, there is provided a control device for a fire extinguishing system operable in response to an alarm signal, said control system comprising:

(a) an alarm emitter capable of emitting a detectable alarm; (b) a means for receiving an alarm signal and, in response to said alarm signal, causing the alarm emitter to emit the detectable alarm; (c) a sensor means for detecting the detectable alarm and capable of generating a signal in response to emission of the alarm; and (d) a control means linked to said sensor means and capable of receiving said signal generated by the sensor means and triggering a delayed operation of the extinguishing system to release an extinguishing material.

For a better understanding of the present invention, reference will now be made, by way of example. to the accompanying drawings in which:

Figure 1 is a fire extinguishing system in accordance with the present invention; and Figure 2 is a detailed view of one part of the system shown in Figure 1.

A battery of bottle cells 1, consisting of high- pressure bottles 2, 2a each containing an extinguishing agent and each, having a high-speed opening valve 3, 3a etc connected by way of connecting lines 5 to a main collecting pipe 4. This communicates with an extinguisher line 6, in which extinguisher nozzles 7 are located. Fire alarms 8 are connected by way of a control line 9 to a fire alarm control system 10. Furthermore a line 24 with manual release 23 is provided. Alarm lines 12 and 13, with alarm transmitters 14 and 15, e.g. acoustic horns or the like, extend from the fire alarm control system 10, associated with which are sensors, such as microphones 16 and 17. Emanating from these sensors are control lines 18 and 19 which lead to an extinguishing control device 11 in the fire alarm control system 10. The extinguishing control device 11 consists of a time control circuit 25 and a contttrol unit 26, which are connected to each other by way of a line 27. The control signals are supplied by means of the lines 18, 19 to an "And/or-gatell 28, from which the signals are supplied, by means of lines 29 and 30. to the time control circuit 25 or the control unit 26. A control line 22 leads from here to a motor 20, through which the activation device 21 of the high-speed opening valve 3 is controlled.

The device 21 corresponds to an electro- W mechanical delay device for activating the high-speed opening valve 3 and is described in detail in DE-OS 38 26 300. With this device 21 the high costs of the pneumatic delay are avoided with which a release can be prevented before expiration of the warning time. As a result of the direct-current motor in the older device there is a very low risk which can occur with a possible stroke of lightning. This can, however. can be eliminated with the use of an alternating-current motor.

In connection with the idea of the acoustic monitoring of the alarm horns 14, 15, the use of the device according to the invention leads to the result that the electromechanical delay device 21 cannot, under any circumstances. run without an acoustic warning. Therefore any type of other necessary expensive control bottles and signal apparatus can be omitted in contrast to the equipment hitherto used.

The microphones 16, 17 can be integrated in the vicinity of the horns 14 and 15 or mounted in the horns integrated as air- sound transducers or structure-sound transducers. This transducer, in connection with an amplifier circuit, only emits a signal if the horn 14 or 15 is functioning orderly. The release signal is supplied to the extinguishing control device 11 in the fire alarm control system 10 and provides that the time control circuit can only run as long as the release signal is present. As a result of the measure according to the invention an absolute guided motion between warning signal and delayed release of the extinguisher gas is achieved without complicated pneumatic or mechanical energy storage, signal devices and release devices being required.

In the nature of the invention, instead of providing the microphone 16, 17, an optical signal transmitter may be provided together with an associated optical sensor which, on sensing an optical signal emits a release signal.

Claims (11)

1. A method for operating a control for fire extinguishers protected against an electromagnetic disturbing influence, in which, in the event of fire, high-speed opening devices of one or more extinguishing agent containers are controlled, after expiration of a early warning time, by an extinguishing control device and the extinguishing agent is released, wherein a signal is emitted by the extinguishing control device to an alarm emitter to trigger emission of a detectable alarm by the alarm emitter and wherein an associated sensor detects the detectable alarm and discharges a release signal to the extinguishing control device, only with ordered operation of the alarm emitter, and the release signal enables the sequence of a time control circuit and the time control circuit controls a control unit for an electric-motor driven release device firstly after expiration of a set early warning time, wherein operation of the control unit is also possible only with application of the release signal and the release device effects, after expiration of a mechanically produced safety time, the release of the extinguishing agent.

2. A method according to claim 1, wherein the extinguishing agent is stored in high-pressure bottles combined in a battery or an extinguishing agent tank.

3. A method according to claim 1 or 2, wherein the extinguishing control device is a component part of a fire alarm control system. 30

4. A method according to claim 1, 2 or 3, wherein the extinguishing agent is delivered by means of highspeed opening valves as high-speed opening devices.

5. A method according to claim 1, 2 3 or 4, wherein the signals for emitting alarms are transmitted by means of electric lines.

6. A method according to any one of claims 1 to -B- 5. wherein the release signals are emitted by way of transducers, which function as air-sound transducers or structure-sound transducers.

7. A method according to any one of claims 1 to 6, wherein the alarm emitter emits an optical signal which is detected by an optical sensor which, in turn, emits the release signal.

8. A method according to any preceding claim, wherein the alarm device is powered by means of a battery and the second alarm device by way of an alternating current network.

9. A method according to any preceding claim, wherein the electric-motor driven release device is activated by means of a direct current motor or an alternating current motor or a stepping switch motor.

10. A method for operating a control for a fire extinguisher system substantially as hereinbefore define, with reference to the accompanying drawings.

11. A control device for a fire extinguishing system operable in response to an alarm signal, said control system comprising:

(a) an alarm emitter capable of emitting a detectable alarm; (b) a means for receiving an alarm signal and, in response to said alarm signal, causing the alarm emitter to emit the detectable alarm; (c) a sensor means for detecting the detectable alarm and capable of generating a signal in response to emission of the alarm; and (d) a control means linked to said sensor means and capable of receiving said signal generated by the sensor means and triggering a delayed operation of the extinguishing system to release an extinguishing material.

Published 1990 at The Patent Office. State House.66 71 High Holborri, London WC1R4TP. Further copies maybe obtained from The PatentOfrice. Sales Branch. St Mary Cray. Orpington. Kent BR5 3BD. Printed by Multiplex techniques ltd, St Mary Cray. Kent. Con. 1187