FI3781270T3

FI3781270T3 - Inspection system for maintenance free fire extinguishing devices

Info

Publication number: FI3781270T3
Application number: FIEP19724619.2T
Authority: FI
Inventors: Peter Kammer
Priority date: 2018-04-16
Filing date: 2019-04-15
Publication date: 2023-01-13
Also published as: DK3781270T3; EP3781270B1; CN111954561B; WO2019202457A3; WO2019202457A2; ES2934861T3; CN111954561A; EP3781270A2

Description

1 EP3781270

European application number: EP19724619.2

European Patent number: EP3781270

Title of the invention: Maintenance-free fire extinguisher with an inspection system

HUOLTOVAPAA PALOSAMMUTIN

TARKASTUSJÄRJESTELMÄLLÄ

Patent proprietor: Kammer Peter

Längackerstrasse 6 4532 Feldbrunnen

Switzerland

2 EP3781270

Maintenance-free fire extinguisher with an inspection system

The present invention relates a fire extinguisher according to the preamble of claim 1.

Stationary or portable fire extinguishers are often used to fight fires in buildings and in transportation means. These fire extinguishers contain an extinguishing agent, which is already under pressure or set under pressure in case of fire and which is then to be sprayed with a defined flow rate and velocity in the direction of the burning material. If there is no more pressure in a fire extinguisher or if the pressure cannot be built up, the fire extinguisher will not work anymore. The functionality of the fire extinguisher must therefore be monitored regularly to determine whether pressure is still present or could be built up in case of use. In addition, status checks must be carried out at defined intervals for certain critical fire extinguisher models.

There are two main types of fire extinguishers available on the market today: stored-pressure fire extinguishers and cartridge-operated fire extinguishers. In stored-pressure fire extinguishers, the container and the extinguishing agent in it are permanently under pressure, so that the fire extinguisher is immediately ready for use when triggered by the user. In cartridge-operated fire extinguishers, the necessary gas pressure is stored in a separate pressurized cartridge in the container. This pressurized cartridge is punctured upon triggering by the user, so that the operating pressure is reached in the container and the extinguishing agent is driven out of the fire extinguisher with the pressure from the pressurized cartridge. The container and the extinguishing agent in it are therefore only set under pressure upon use.

In order to check the operational readiness and the internal pressure of stored- pressure fire extinguishers, they are often equipped with a manometer, as described for example in EP 2759823 A2, EP 1311323 B1 and EP 2938410 B1.

3 EP3781270

Manometers are sensitive measuring instruments which can indicate incorrect pressure values over the years. Common manometers consist of movable measuring parts, which deform elastically due to chemical reactions or due to the effect of vapors. These measuring parts are connected to a pointer or to an electronic sensor, which derives a pressure value from this movement or deformation. However, in the case of fire extinguishers, the pointer of the manometer usually remains motionless for years. In the course of time, in addition to chemical reactions, condensation water can form in the manometer and metallic parts may therefore corrode. So, there is a risk that the known manometers solidify and no longer reflect the actual pressure, and thus that a pressure loss of the extinguishing agent is not detected. A further disadvantage of conventional stored- pressure fire extinguishers is the fact that the container is usually made of metal.

Containers made of metal have latent corrosion risks caused by the aggressiveness of the extinguishing agent. Stored-pressure fire extinguishers must therefore be opened regularly to check the inside of the container and to check the function of the manometer. In order to reduce the risk of corrosion, fire extinguishers with fiber-reinforced plastic containers are used. In EP 2473770 A1, for example, two layers of fibers are wound around the container in different directions. However, even fire extinguishers with containers made of corrosion- resistant material must still be serviced regularly to check the function of the manometers.

Cartridge-operated fire extinguishers were developed to make it easier to check the inside of the metallic container, as it is not under permanent pressure (see e.g.

EP0867205A1). Cartridge-operated fire extinguishers are still opened annually or every 2-3 years, depending on the applicable regulations, in order to check the condition of the container and of the metallic pressurized cartridge. The disadvantage of this practice is that extensive maintenance work has to be carried out just to determine whether the internal coating of the containers is still in order and whether the pressure bottle still has sufficient pressure and is not damaged by corrosion. Another disadvantage is that if the pressure bottle does not function

4 EP3781270 between two maintenance intervals, this is not visible from the outside. The fire extinguisher therefore remains sealed, even if the pressure cartridge is no longer functional. This situation is deceptive for the user, who assumes that a sealed fire extinguisher works properly.

In summary, it can be said that today's fire extinguishers must be regularly serviced and even opened to determine whether the container and, in the case of rechargeable fire extinguishers, also the internal pressurized cartridge, are corroded or still operational. This work has to be carried out by a specialized expert and causes high costs and a considerable logistic effort.

The object of the present invention is to provide a fire extinguisher with an inspection system which allows to check the operational readiness of the fire extinguisher at any time reliably with a simple visual inspection and without special technical knowledge. Thus, expensive and complex inspection and maintenance work by a specialized expert is to be replaced by simple visual inspections by a layman. A further object of the invention is the signalling of a possible malfunction detected by the inspection system by means of a communication system, so that this malfunction can be automatically reported and immediately remedied after its occurrence.

These objectives are achieved by a fire extinguisher according to claim 1. Further features and embodiments can be found in the dependent claims and their advantages are explained in the following description.

The basis of the invention is a fire extinguisher with an inspection system that measures the internal pressure of a corrosion resistant, heat/cold resistant and vibration resistant pressure vessel. In a stored-pressure fire extinguisher, the pressure vessel directly contains the extinguishing agent, in a cartridge-operated fire extinguisher, the pressure vessel is located inside the extinguishing agent container. The display of the internal pressure allows anyone, even a layperson, to

EP3781270 directly determine whether the pressure vessel is still under sufficient pressure, i.e. whether the fire extinguisher is ready for operation. According to the invention, two main measures improve conventional fire extinguishers, especially those with long maintenance intervals: 5 * the inspection system with improved, more reliable means for controlling the internal pressure; and e the production of the pressure vessel from corrosion-resistant, heat and cold resistant and vibration-resistant material.

These two measures are essential to ensure the required high reliability of pressure measurement and display, costly inspection and maintenance work is thus unnecessary and may be replaced by a simple visual inspection. These measures are a prerequisite to ensure operational readiness at all times, especially for fire extinguishers with long maintenance intervals.

Inspection system

The inspection system comprises at least two pressure measuring devices, e.g. manometers, pressure sensors, etc., which measure the internal pressure of the pressure vessel independently from one another.

In a possible embodiment of the invention, the pressure measuring devices are arranged in isobaric regions of the pressure vessel, so that they should measure the same pressure values. A too large deviation between the pressure values is thus a sign of a malfunction of at least one of the two pressure measuring devices or of another problem, which however does not necessarily affect the operational capability of the fire extinguisher.

The pressure measuring devices can be arranged next to each other at the same location or at two separate locations of the pressure vessel. According to the invention, the inspection system with the pressure measuring devices is provided as a single and compact part. However, to ensure that the pressure measuring

6 EP3781270 devices are as independent of each other as possible and are not exposed to the same damage, they are not in direct contact with each other and are oriented differently, according to the invention. Ideally, they are mounted at different locations and have no common functional parts to prevent a small defect from affecting the functionality of multiple pressure measuring devices simultaneously.

According to the invention, each pressure measuring device has a separate opening to the inside of the pressure vessel to prevent a local problem from affecting several pressure measuring devices simultaneously. To further reduce this risk, it is advantageous if the pressure measuring devices are based on different pressure measuring methods (e.g. analog / digital).

The inspection system is eguipped with a comparison unit which acguires the pressure values and compares them with each other and/or with one or more predefined target values. If the comparison shows that one or more pressure measuring devices give inconsistent measured values or values that do not correspond to the expected target value, an error message is displayed or triggered. Depending on which values do not correspond to the expected target value, it will indicate that there is only a problem or that the fire extinguisher is no longer operational at all.

The inspection system also has an output system to signal the measured values and/or possible error messages. It is especially advantageous if the output system is a display unit that allows a visual inspection so that the operational status can be determined without maintenance. The display unit can, for example, be a dial with a moving pointer, or a digital display. In possible embodiments of the invention, the output system comprises additionally or instead of the display unit, a loudspeaker or buzzer for emitting an acoustic signal, e.g. for error messages. A color display for gradation of the operational status with for example green (full operational readiness), yellow (problem is present) and red (no operational readiness) is also conceivable.

7 EP3781270

Communication system

In another preferred embodiment, the output system is additionally equipped with a communication system, which includes a communication unit and a signalling device, for the transmission of the measured values and/or possible error messages to a remote control unit. The signaling device can output an acoustic signal and/or a light signal. It therefore comprises a loudspeaker and/or a buzzer and/or a light bulb and/or one or more diodes which are triggered and activated by the communication unit when a signal is received. In case of fire or if a repair or inspection is necessary, the fire extinguisher eguipped with the communication system according to the invention can thus be located easily and quickly.

The communication unit can also have at least one receiver that can receive and process a signal from the environment. In a possible embodiment of the invention, the receiver is a fire sensor and the signal received is the presence of smoke (in the case of a smoke sensor) or an increased temperature (in the case of a temperature sensor). In another possible embodiment of the invention, the receiver receives a signal from a central fire fighting system, from a mobile device, from a fire detector or from another fire extinguisher. The signal can be transmitted wirelessly (via radio, Wifi, Bluetooth, etc.) or electrically via a wire connection. This signal can be an information or status reguest or a fire alarm, which activates the signaling device to generate the signal intended for this case. In the preferred embodiment of the invention, the communication system is provided with at least two receivers, including at least one fire or temperature sensor for activating the signalling device in response to a local fire event and at least one receiver for an electrical or electromagnetic signal for activating the signalling device due to a request from another device.

It is particularly advantageous if the communication unit also includes a transmitter with which fire alarms or other information such as operational status notifications can be transmitted to a central fire fighting system, to a fire control system, to an

8 EP3781270 inspection or control point, to other fire extinguishers or to mobile devices. In a possible embodiment of the communication system, the receiver is a fire sensor which is connected to the transmitter so that a fire can be detected and a fire alarm can be issued. Several fire extinguishers equipped with the localization and communication system according to the invention can thus interact, exchange data such as fire alarms and form a large networked fire fighting system. It is also conceivable to connect several such fire extinguishers to a central control unit to create a coordinated, centralized fire fighting system.

In a possible variant of the invention, the communication system according to the invention serves not only to locate a fire extinguisher in case of fire, but also in other situations, e.g. in case of repair or replacement of the device. This work on the fire extinguisher is usually carried out by external, specialized companies, and the respective persons are often not familiar with the premises and the location of the fire extinguishers. Each fire extinguisher must therefore be searched for. In order to reduce this effort, the receiver can also activate the signalling device based on a received signal which is not a fire alarm. For example, an inspector could pass by the premises with a smartphone or a tablet, trigger the signal, activate the signaling device from a distance and, based on the activated signal, easily and guickly locate fire extinguishers eguipped with the communication system of the invention and determine their operational status, carry out necessary repair work or replace a defective fire extinguisher.

In further possible embodiments of the invention, the fire extinguisher eguipped with the communication system can be located with GPS positioning.

In the normal state, the transmission of data by the communication unit is carried out, for example, dynamically as soon as a malfunction is detected, or periodically at regular intervals, or upon interrogation of the remote control unit/control point, or even automatically as soon as the control unit is located near the communication system. For example, a maintenance technician could simply walk by the fire

9 EP3781270 extinguishers equipped with the inspection and communication system and automatically receive notifications or measurements on his mobile device (the control unit) to record and, if necessary, log the operating status of the fire extinguishers.

Pressure vessel

It is Important that the pressure vessel be made of corrosion resistant, heat/cold resistant and vibration resistant material so that it is not affected by external influences such as humidity, vibration and temperature. Heat and cold resistant materials are materials that can withstand the internal pressure of the vessel over a wide range of temperatures, from negative temperatures to very high temperatures that can occur near a fire. Furthermore, it is important for a stored- pressure vessel that there be no oxygen in the pressure vessel but a noble gas, e.g. nitrogen, in order not to negatively influence the long-term stability of the extinguishing agent.

According to the invention, the material of the container can be printed on directly so that relevant information (instructions, notes, etc.) can be printed directly on its surface without the need for a separate sticker, which may fall off over time.

Suitable materials for the pressure vessel are, for example, plastics or resins, which can also be used in combination with other materials in the form of composites. The use of a composite consisting of a flexible matrix with reinforcing fibers made of a material with high tensile and tear strength is particularly advantageous. For example, PEEK (polyether ether ketone), aramides (especially

Kevlar) or resins (especially epoxy resin) can be used to manufacture the various components of the pressure vessel, either individually or as a matrix of a composite material. Suitable reinforcing fibers for composites are for example aramid fibers (especially Kevlar fibers) PEEK fibers or carbon fibers. In the

EP3781270 preferred embodiment, the pressure vessel is reinforced with one or more Kevlar fibres, which are wound several times around the vessel.

With the measures described herein, a fire extinguisher with pressure vessel and inspection system is provided, which can be reliably checked for operational capability with a simple inspection of the inspection system. Thus, expensive and complex inspection and maintenance work by a specialized expert can be replaced by simple visual inspections by a layperson, e.g. the operator. In addition to checking the operational readiness of the fire extinguisher, the visual inspection can also be used to check at any time and without specialist knowledge whether all the eguipment of the inspection system, such as measuring instruments and comparison unit, are functioning properly or whether they need to be serviced or even replaced.

In addition, it is intended that a possible malfunction of the pressure vessel, of the fire extinguisher and/or of a component of the inspection system is automatically signaled to a remote control unit by the inspection system.