EP1332773B1 - Method for controlling a stationary extinguishing installation - Google Patents

Abstract

The control method uses a fire detection device (2) with one or more fire detectors (4) having different sensors for detecting fire parameters, compared with preset alarm thresholds for providing an alarm indication, used for triggering the fire extinguishing devices (1). Selected sensors are switched to an increased sensitivity after triggering the fire extinguishing devices, the selected sensors matched to the progression of the fire.

Description

The present invention relates to a method for controlling stationary extinguishing systems, in particular for controlling extinguishing devices, which are operated with liquid or gaseous extinguishing agents.

Essential components of stationary extinguishing systems are, in addition to the extinguishing devices for liquid or gaseous extinguishing agents, the fire detection devices in the center of the invention for controlling extinguishing equipment.

Fire extinguishers have an extinguishing agent reservoir with liquid or gaseous extinguishing agents, which is connected via a more or less branched piping system with the surveillance area (building, warehouse, etc.) of the extinguishing system.

In case of fire, the release of the extinguishing agent is carried out by means of extinguishing nozzles, the design of which is specially designed for the extinguishing task.

Depending on the type of fire hazard and the areas to be protected come widespread sprinkler or Feinsprühanlagen which produce a highly effective water mist or gas extinguishing equipment with an inert gas such as carbon dioxide as extinguishing agent used.

For effective fire fighting, the timing of triggering the various extinguishing equipment plays a special role.

This task is performed by fire alarm systems, which are usually equipped with detectors for the early detection of different fire characteristics.

One or more detectors are housed in fire detectors, which are often connected via signal lines (reporting lines) with a fire alarm panel. Fire alarm systems are usually constructed from a variety of robust fire detectors. The detectors react to the generation or change of measurable fire parameters such as temperature, radiation, aerosols or a fire characterizing gases.

In the fire alarm panel, the incoming measuring signals of the fire detectors are processed from the monitoring area of the extinguishing system and, in the event of an alarm, corresponding control commands are transmitted to the extinguishing device.

The term fire parameters is intended to summarize all physical or chemical changes of state parameters that are essentially caused by a fire and that can be detected by sensor elements or detectors in the monitoring area of a fire alarm device.

For example, fire parameters are such parameters as ambient temperature, gas composition (smoldering or combustion gases), the density of optically detectable smoke or soot particles (aerosols) and emanating from fires electromagnetic radiation in different wavelengths.

Stationary extinguishing systems are successfully used in many areas of fire protection of buildings, facilities or in the storage of goods for automatic fire fighting.

As is known, the triggering of the deletion process and the release of the extinguishing agent by automatically operating fire detection devices.

In order to be able to detect the formation of a fire at an early stage, the fire detectors should be located on the one hand as close as possible to a possible place of origin of fires, on the other hand, however, the local conditions must also be considered.

In addition to the early detection of fires, the focus of the further development of fire alarm systems is the prevention of false alarms.

False alarms are often triggered by uncritical or process-related sources of smoke aerosols or gases. Even a temperature increase in the environment of a heat detector, which can not be attributed to an incipient fire, can lead to a false alarm.

In many conventional extinguishing equipment, the fire extinguishing agent supply is often consumed without interruption after a fire alarm has been triggered and the extinguishing process has been activated.

For smaller localized fires, however, such extensive extinguishing measures are usually not necessary.

Even greater damage is caused by false alarms.

Not only the extinguished extinguishing agent supplies (CO ₂ gas) that are used up and limited in certain extinguishing systems then have to be replaced costly and time-consuming, the extinguishing agents released unnecessarily can cause damage to persons and facilities or paralyze entire production areas.

To solve these known problems in the operation of stationary extinguishing systems numerous proposals have been made.

Out DE 100 12 705 A1 is a method and an apparatus for early detection and

Fighting of fires in the interior and exterior, in particular living area of houses and buildings with an extinguishing device and a fire detection device comprising one or more fire detectors with at least one detector out, the detectors detect the same or different fire characteristics and exceeding one or more presettable Alarm thresholds of the detected fire parameters trigger an alarm message that activates the extinguishing device.

Out DE 41 42 419 A1 For example, there are known a method and a device for detecting fire in a monitored space with the possibility of increasing the sensitivity of the detector system, wherein no specific number of detectors are switched with respect to their sensitivity and the number of detectors to be switched is adapted to the further course of the fire.

Out DE 2344908 C2 discloses a method for the automatic notification and extinguishing of fires, in which the fire extinguisher is first activated and operated after a flame message is present, which must have been preceded by two smoke messages or a heat message.

In this case, the persistence of the flames should be checked at certain intervals by a flame detector and the extinguishing agent delivery either maintained or turned off.

How the review should be accurate, however, is not specified.

By means of this known solution false alarms and damage due to unnecessary extinguishing agent influence should be avoided.

A similar extinguishing method with a spatially distributed sensory detection of the fire and an adapted according to the spatial fire development extinguishing agent delivery is in the DE19627353 C1 described.

Also in the DE19952327 A1 discloses a fire sensor and a method of detecting a fire, wherein the smoke signal emitted by the fire sensor is additionally corrected by the correlating current outside temperature and the temperature rise speed.

This is intended to adapt the smoke detection sensitivity of the sensor to the ambient temperature and its rate of change.

According to this method, the likelihood of a false alarm should be reduced and at the same time an early alarm triggering should be achievable.

However, it only relates to the detection of fires until the extinguishing device is activated and contains no indication of the deletion process and the control of the extinguishing device after the alarm was triggered.

GB 2 188 725 describes a detector and a detection system in which the sensitivity of the signal strength dependence is adjusted while being adjusted for smoke or smoke density. It can not be deduced from the document that the detector is to be used in connection with the activation of an extinguishing device and reacts to quantities which are directly related to the extinguishing procedure.

The previously known fire alarm systems have the particular disadvantage that caused by a fire and the onset deletion physical and chemical changes in the environment of fire detectors, such as heavy smoke, soot particles, temperature changes by Löschwassereinfluß or water mist, and in the gas composition, etc., not taken into account become. Without taking into account these changes in the fire area conventional fire alarm systems can not provide a sufficiently accurate picture of the current fire happen and are only limited to control the deletion process.

Based on this method and the known stationary fire extinguishing systems and fire detection systems, it is an object of the present invention to develop a method for controlling stationary extinguishing systems, with which it is possible to installed detectors even after fire detection under changed chemical and physical conditions of the extinguishing process in the fire use.

The method should make it possible to generate well-evaluable and suitable for controlling the extinguishing device in spite of changing fire conditions in changing environmental conditions of the fire detector and to use for effective control of the deletion process.

According to the invention, this object is achieved by a method according to the characterizing features of the first claim. In the subclaims further advantageous embodiments of the invention are given.

The extinguishing method according to the invention is characterized in that the detectors of the fire detectors after the first safe detection of a fire by exceeding one or more preset alarm thresholds are switched to an increased sensitivity level. This makes it possible to continue to effectively detect the fire despite smoke or vapor formation by evaporating extinguishing agent and other disturbing influences.

Furthermore, a fire detection device according to the invention for carrying out the method is given.

The method can be used particularly advantageously using infrared detectors as sensitive flame detectors in the fire detectors.

The heat radiation occurring during fires can still be reliably detected by the inventive increase in the sensitivity of an infrared detector, even when caused by the fire reduction in the permeability of its ambient air. Furthermore, it is envisaged to make a local selection of the detectors to be converted to a higher sensitivity following the progress of the fire.

In areas with less smoke or a short distance from the fire, a lower sensitivity is required than in areas with heavy smoke or a large distance from the fire.

The control takes place via the temporal behavior of the fire parameters.

An advantageous development of the method according to the invention consists in the possibility of setting the switching processes (signal evaluation of the detectors) to increase the sensitivity of the detectors at a selectable time interval after the detection of the beginning of the fire.

By means of this flexible adjustment, can be worn with a well-known in general hazards of the objects to be protected an expected fire development.

The individual switching operations of the detectors to a higher sensitivity level This is done by a control unit located in the fire detectors or by the fire alarm control panel.

For this purpose, the measured data transmitted by the detectors are used for the current local fire development.

In this case, a gradual increase in sensitivity is just as within the scope of the invention as a stepless continuous increase.

The local or spatial selection of the switches to be switched to increased sensitivity takes place after evaluation and taking into account the measured data transmitted to the fire alarm control panel.

In this case, the fire detectors can be arranged at different locations and one of the structure of the expected fire risk potential corresponding orientation, which can be the fire during the deletion process continuously analyzed from several directions.

A further advantageous embodiment of the invention consists in the additional arrangement of a detector element in one or more fire detectors for monitoring the continuous extinguishing agent use.

A fire extinguishing sufficient extinguishing agent use is detected by this additional element and generates a clear stop signal for automatic shutdown of the extinguishing device.

A further advantageous embodiment of the invention is associated with the known method of cyclic extinguishing agent application with controlled extinguishing agent delivery.

Since, in accordance with the invention, the sensitivity of the detectors is tracked in the event of a fire, an accurate image of the current fire progression, which corresponds to the current measured data, is produced.

If the analysis of the measurement data of the detectors indicates a continuation of the fire, an expired erase cycle of the extinguishing device is restarted.

If fire is no longer detected despite the higher sensitivity of the fire detector, the generation of the activation signals (triggering) to control the extinguishing device is also aborted and the deletion process is terminated.

To ensure further safety for the complete extinguishment of a fire, after the generation of a clear stop signal by the fire alarm device, a presettable extinguishing cycle is triggered.

The parameter settings for the post-erase cycle, such as erase duration and

The amount of extinguishing agent depends on the degree of endangerment of the objects to be protected.

Fig. 1:

Prinzipieller Aufbau einer stationären Löschanlage mit Brandmeldeeinrichtung und Löscheinrichtung

Fig.2:

Brandmelder mit elektronischer Steuerung und Detektoren

Fig.3:

Zeitliches Ablaufschema des erfindungsgemäßen Löschverfahrens

The invention will now be explained in more detail with reference to an exemplary embodiment. The figures show:

Fig. 1:

Basic structure of a stationary extinguishing system with fire alarm device and extinguishing device

Figure 2:

Fire detector with electronic control and detectors

Figure 3:

Timing diagram of the deletion method according to the invention

Fig. 1 shows the basic structure of a stationary extinguishing system, with an extinguishing device 1 and a fire detection device 2, which in particular includes a plurality of fire detectors 4 and their signal lines 13 and their essential elements are arranged in the monitoring area 3.

The extinguishing device 1 has an extinguishing agent supply, which may consist of several compressed gas cylinders in gas extinguishing equipment, for example, and a more or less branched piping network for transporting the extinguishing agent to the fire in the surveillance area. The trigger mechanism for the deletion process, for example an alarm valve station, is connected via signal lines 13 to a fire alarm device 2. In this case, the fire detection device 2 include one or more fire detectors 4, in turn, one or more detectors 5,6 the same or different types are integrated. The detectors 5, 6 are preferably designed as optical radiation detectors whose radiation sensitivity lies in the infrared or ultraviolet wavelength range.

In the fire detectors are even more electronic components 7 for control and

Signal processing of the detectors 5,6 and the extinguishing device 1 integrated.

For larger stationary extinguishing systems takes over a fire alarm panel 8, the control of the extinguishing device 1 and the evaluation of the detector signals of the individual fire alarm. 4

In this exemplary embodiment, the control unit 7 for the extinguishing device 1 and the detectors 5, 6 are integrated into the fire detector 4. The fire detector 4 is connected via signal lines 13 to the extinguishing device 1 ( Fig. 2 ).

In order to avoid the triggering of false alarms of the extinguishing device by interference variables (eg infrared radiation sources), the amplifier circuits 11, 12 of the detectors 5, 6 are adapted to the ambient conditions of the fire detector.

This adaptation (temperature compensation, resting value tracking) can be realized, for example, with the aid of digital / analog converters, which are controlled by the control unit 7 of the fire detector 4.

If, by means of one or more detectors 5,6, increased radiation values from the monitoring area 3 are measured and a predefined alarm threshold value is exceeded, the fire detector 4 transmits an alarm signal to the extinguishing device 1 and activates the automatic deletion process.

In this case, it may well be appropriate to switch adjustable pre-alarm levels before the activation of the automatic deletion process or to use other fire characteristics for fire detection.

The detectors 5, 6 can expediently be arranged individually or jointly in a fire detector 4 and detect identical or different fire characteristics (type A or type B).

After activation of the extinguishing device 1, the detectors are 5.6 set by means of amplifiers 11,12 to a higher sensitivity.

This makes it possible to detect the further course of fire through the resulting smoke or steam and extinguishing mist.

As long as the detectors of the fire detector detect the fire with an increased sensitivity level 9 ( Fig. 3 ), the extinguishing device 1 is still triggered (triggered) and a preset erasing cycle 15 is restarted ( Fig. 3 ). The erase process can thus consist of a plurality of erase cycles 15 and is continued until the detectors of the fire detectors no longer detect fire.

After detection of the fire end, the fire detectors 4 transmit no further trigger signals to the extinguishing device 1 and the deletion process is deactivated after the expiry of a preset extinguishing time.

The preset post-extinguishing time 15 is activated by means of the clear-stop signal generated by the control unit 7.

Subsequently, the detectors are reset by means of amplifier 11,12 back to normal (default) sensitivity.

The fire alarm device 2, in particular its fire detector 4 may additionally be equipped with another suitable detector element 10 for monitoring the use of extinguishing agent in case of fire.

If an extinguishing agent use sufficient for firefighting is detected by the detector element 10, the generation of an extinguishing stop signal and the activation of a preset extinguishing time are also effected here.

An extinguishing agent is sufficient if, for example, in a gas extinguishing device, the quenching gas concentration (CO ₂ content) is high enough to stifle the fire.

As a suitable detector element 10 for monitoring the use of extinguishing agents, for example, a CO ₂ sensor can be used in a CO ₂ extinguishing system or an O ₂ sensor in a gas extinguishing system.

Depending on the design of the stationary extinguishing system, the extinguishing stop signal of the detector element 10 is either processed in the control unit 7 of the fire detector 4 or in a fire control panel 8 and transmitted to the extinguishing device 1.

The extinguishing method according to the invention has the particular advantage that the extinguishing agent used is very targeted and adapted to the fire course.

If a fire is successfully combated, the extinguishing agent supply is interrupted and further damage to persons or facilities is avoided.

It is achieved a significant reduction in the amount of extinguishing agent.

The continuous or incremental increase in the sensitivity of detectors of the fire detector after the first alarm triggering allows a differentiated assessment of the real fire occurrence.

LIST OF REFERENCE NUMBERS

1

extinguishing device

2

Fire alarm device

3

monitoring area

4

fire alarm

5

Detectors type A

6

Detectors type B

7

Control unit with memory (integrated in the fire detector)

8th

Fire Panel

9

Signal "Fire detected" by fire alarm

10

Detector element for the clear stop signal

11

Amplifier circuit A

12

Amplifier circuit B

13

signal lines

14

Start of the deletion process

15

Nachlöschzyklus

16

Point at which switching to high sensitivity occurs

17

Normal sensitivity on the timeline

18

Cancel Stop, extinguishing time expired

Claims (8)

1. A method of controlling fixed fire-fighting systems with a fire-fighting device (1) and with a fire alarm device (2) incorporating one or several fire alarms (4) with at least one detector (5, 6), said detectors (5, 6) detecting the same or different fire parameters and issuing an alarm activating said fire-fighting device when one or several of the pre-adjustable alarm thresholds of the detected fire parameters are exceeded, characterized in that, when the pre-adjusted alarm thresholds of one or several of the fire parameters are exceeded and upon activation of said fire-fighting device (1), at least one of the detectors (5, 6) switches to increased sensitivity and that the selection of the detectors (5, 6) to be switched to increased sensitivity is adapted to further fire progression in terms of space and time.
2. The method as set forth in claim 1, characterized in that one or several detectors (5, 6) are switched to increased sensitivity at the same time the fire-fighting device (1) is being activated or within a variably selectable time interval after activation of said fire-fighting device.
3. The method as set forth in claim 1 or 2, characterized in that evaluation of the detector signals and adjustment of the sensitivity of the detectors (5, 6) as well as selection of the detectors to be switched to increased sensitivity for optimal detection of fire progression occur from a control unit (7) disposed in the fire alarm (4) or from a Central Indicating Equipment (8).
4. The method as set forth in any one of the previous claims, characterized in that switching one or several detectors (5, 6) to increased sensitivity occurs gradually or continuously.
5. The method as set forth in claim 4, characterized in that the fire alarms (4) or/and the detectors (5, 6) are disposed at different places in an orientation corresponding to the structure of the fire hazard potential to be expected and that fire progression is permanently analyzed from several directions during fire-fighting and that a stop signal for stopping fire-fighting is delivered once the fire has stopped.
6. The method as set forth in any one of the previous claims, characterized in that a suited detector element (10) for monitoring the permanent use of fire-fighting agents is added in one or several fire alarms (4), said suited detector element generating a stop signal for stopping fire-fighting when enough fire-fighting agents have been used for fighting the fire and transmitting this signal to a control device (7, 8) so that fire-fighting is stopped.
7. The method as set forth in any one of the previous claims, characterized in that, after first activation of the fire-fighting device (1) and after the fire alarm device (2) has been switched to an increased sensitivity stage, and after the first fire-fighting cycle has been performed, when fire hazard is still given, additional activation signals (trigger pulses) are transmitted in variable time intervals by the fire alarm device (2) to the fire-fighting device (1), said activation signals restarting a completed fire-fighting cycle, the thus controlled fire-fighting cycles being repeated until it is detected that the fire has stopped.
8. The method as set forth in claim 7, characterized in that the control device (7, 8) of the fire-fighting device (2) or of the fire alarm (4) delivers to the fire-fighting device (1) a stop signal for stopping fire-fighting once it has been detected that the fire has stopped, this signal enabling a post-fire fighting cycle the scope of which is pre-adjustable.

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