EP4146357B1 - Improved extinguishing lance for electrical applications - Google Patents

Description

The invention relates to an extinguishing lance for fighting fires in electrically charged objects, such as vehicles equipped with electric motors, wherein the extinguishing lance has a holding section with a handle for an operator, an extinguishing agent supply with a coupling device for connecting a pressure hose for liquid extinguishing agent, and a tubular extinguishing section connected to the holding section and optionally the coupling device, from the free end of which extinguishing agent can be introduced into a burning object under pressure, wherein the handle of the holding section has a voltage-insulating coating which is also designed to be electrically insulating for electrical voltages U between 500V and 1000V, wherein the tubular extinguishing section is made of a material which has such a high tensile strength R _m that it withstands a mechanical stress σ ≥ 500 N/mm ² and which has a melting temperature ts ≥ 650°C, wherein the tubular extinguishing section is geometrically tapered at its free end and has a narrowed clear flow cross-section for the extinguishing agent passed through under pressure, wherein the tubular extinguishing section and also the tapered free end of the tubular extinguishing section are made of stainless steel, and wherein the tapered free end of the tubular extinguishing section is additionally hardened.

Such an electric fire extinguishing lance is known from the DE 20 2017 104 411 U1 as well as from the WO 2019/020507 A1 .

Conventional extinguishing lances, which are not suitable for extinguishing objects that are under high electrical voltage, are described in the company catalog of Murer Feuerschutz GmbH from 05/2016, in particular the "Fog extinguishing system NLS" shown there.

Background of the invention

For reasons of environmental and climate protection as well as sustainability, there are currently intensive international efforts to use more electrical energy instead of fossil fuels. In recent years, photovoltaic systems have increasingly been installed, for example on building roofs. In addition, individual mobility will increasingly be made possible by electric drive systems, for example by electric vehicles.

However, little attention has been paid to the fact that such an increased use of electrical energy also entails considerable potential dangers.

These potential dangers are already becoming increasingly apparent in view of the numerous fire incidents occurring worldwide due to non-functioning or poorly functioning batteries, for example in smartphones or notebooks.

A particularly high risk is seen in fires in the vicinity of electric vehicles, for example in hybrid or fully electric vehicles (see, for example, "E-Mobil-Brand in den USA"; https://www.welt.de/motor/news/articlel20704501/E-Mobil-Brand-in-den-USA.html (accessed on 09.11.2016)).

What is particularly problematic when an electric vehicle catches fire is that not only are there significant risks associated with the fire itself and possible self-igniting elements such as lithium-ion batteries, but there are also risks associated with spreading high voltages and high currents due to the high-performance electrics and batteries installed in the vehicle. It is therefore important to prevent these effectively.

In the US-A 4,802,535 A fire extinguishing lance is described in which hardened steel pipe is proposed as the material for the tubular extinguishing section. However, electrical insulation of any kind for the known extinguishing lance is not provided.

The US 2003/0159837 A1 shows a "multi-purpose water hammer" with a tapered nozzle that is intended to penetrate an object to be extinguished when used. The extinguishing head is placed at an angle of 90° on the tubular extinguishing section. For a hammer-like use of this device on an electric vehicle, the impact on the outer shell of the vehicle would have to be very close to the battery to be extinguished in order to achieve any effective effect. In addition, there is no electrical insulation of the extinguishing lance or In 2002 and 2003, people probably didn't think about electric vehicles like they do today.

In the US 2002/019307 A1 Although insulation against electrical voltage when in contact with wires in a building wall is indicated, there is no insulation against high voltage, such as that found in batteries in electric vehicles. In addition, the extinguishing agent is fed in via the end of the known extinguishing lance, so that it is not possible to drive the lance into the outer shell of a vehicle with an impact tool. Such a conventional extinguishing lance is suitable for extinguishing buildings and possibly also burning conventionally powered vehicles, but by no means for extinguishing burning electric vehicles, mainly because of the high electrical voltages U >> 200V that are to be expected there - in contrast to normal buildings (apart from power stations) and normal vehicles.

This is demonstrated, among other things, by the journal article " MOBILE LIFE-WHAT IF THERE'S A FIRE?" from the magazine "stern" dated 19.06.2019 , p.80. It is popularly presented in this article that electric vehicles with high-voltage batteries - which, as is well known, are to replace conventional vehicles powered by combustion engines as completely as possible in the very near future for environmental reasons - pose a very considerable risk to the life and limb of the firefighters who are supposed to extinguish such burning electric vehicles.

It is quite obvious that such an extinguishing operation cannot be carried out with the necessary safety using a conventional fire lance of the type described above.

Instead, EN 10 2016 211 854 B3 or. EP 3 263 402 B1 A special container was proposed which contains extinguishing water into which a burning electric vehicle is to be completely immersed - a truly desperate idea:
Imagine this: an electric vehicle catches fire on a busy street. But instead of putting out the burning vehicle on the spot, as is usual, the fire brigade must first bring a huge special container, fill it with a huge amount of extinguishing water on site and then - somehow, however - dip the electric vehicle, which is still burning but will probably have completely burned out by then, into this large container. How this is supposed to be done with a larger vehicle such as an electric bus or truck remains completely unclear.

The magazine article " ELECTRIFYING OPERATION" from the fire service magazine "BRANDHEISS" in the July-August 2018 issue, p.16 , describes from the point of view of the expert - namely the fire brigade - the new and very dangerous situation for the firefighting experts on site when extinguishing a burning electric car. It literally says here: "Although the burning electric van was of a rather manageable size, the comrades of the Traun fire brigade were certainly challenged." ... "The firefighting operation was particularly precarious in the initial phase, as vehicles with electric drives are to be extinguished and treated completely differently than normal cars. An initial firefighting operation using breathing apparatus quickly had an effect, but the vehicle had to be "water bathed" - as is intended for such fires - because the burned and destroyed batteries still pose an enormous fire risk several hours later. Therefore, the destroyed vehicle was towed on a truck tow truck by two fire brigade vehicles with blue lights directly to a Traun industrial area where it was immersed in a deep water bath protected against leakage." ... "BIG EFFORT FOR A SMALL VEHICLE" ...

This underlines the high urgency of finding a technically much better, safer and also much more economical solution to the problems of extinguishing burning electric vehicles than, for example, EN 10 2016 211 854 B3 or. EP 3 263 402 B1 suggested.

In addition to the actual fire-fighting problems, the extremely negative consequences for the environment must also be considered: After the fire-fighting operation described above, the destroyed vehicle was also placed in a "water bath" and "dunked" with enormous effort. But even before that - and specifically through the actual fire-fighting process - an enormous amount of highly contaminated fire-fighting water had already been released into the environment, which the article does not report on further.

When a vehicle catches fire, the usual and well-known mixture of respiratory poisons is always produced. In addition, there are other, very significant amounts of very dangerous respiratory poisons as a result of the "thermal runaway" of the lithium-ion battery. Lithium hexafluorophosphate (LiPF), hydrofluoric acid (HF), phosphoryl fluoride (POF) and phosphoric acid are released primarily as a result of the decomposition of the conductive salt in the electrolyte. When a burning or still smoldering electric vehicle is transported further, these dangerous substances continue to escape and contaminate the surrounding area. Using the electric fire extinguishing lance according to the invention also reduces this pollution. the environment is significantly reduced and only a small amount of water (20-50 liters) is contaminated by the fire-fighting operation.

To date, firefighters have been only partially prepared, and generally not at all, to deal with such sources of danger. For example, the articles mentioned above report that firefighters fighting a fire in an electric vehicle kept or had to keep a considerable distance from the electric vehicle, which of course significantly limits the effectiveness of the firefighting or reduces the positive effect of the known firefighting measures, if not makes them impossible.

In order to deal with such increased risks, a completely new type of electric fire extinguishing lance is required, which is not only designed for actual fire extinguishing, but can also withstand thermal, mechanical and , in particular, electrical hazards.

For the first time with the electric fire extinguishing lance of the type defined above in accordance with DE 20 2017 104 411 U1 as well as WO 2019/020507 A1 The state of the art has made it possible to protect the extinguishing tool against thermal and/or mechanical hazards and also to provide it with high-voltage protection.

However, this new type of electric fire extinguishing lance does not fully and comprehensively ensure that the - comparatively strict - legal standards for electrician's tools can be complied with. There is still a risk that when extinguishing live electrical objects - especially when the fire extinguishing lance is wet, which is typical for the application - - electrical voltages or currents from the electrically non-insulated tubular extinguishing section can reach the operator to an unacceptably high extent, which could potentially cause serious injury or even death during firefighting operations.

Object of the invention

In contrast, the object of the present invention is to provide an electric fire extinguishing lance of the type defined at the outset using the simplest possible technical means in a simple and cost-effective manner, with which the minimum requirements for protection against thermal hazards as well as for protection against mechanical overloads and for protection against electrical hazards are reliably met.

Brief description of the invention

According to the invention, this task - which in practice is life-saving and life-saving for the operator - is solved in a surprisingly simple and effective manner by an electric extinguishing lance of the type defined at the beginning, which is however suitable for really safe work under electrical voltage, in that the tubular extinguishing section has, at least in the area of the holding section and also outside the handle part, a voltage-insulating coating which is designed to be electrically insulating for electrical voltages U ≥ 500V.

The present invention provides an electric fire extinguishing lance that completely solves the above-mentioned inventive problem. In particular, the electric fire extinguishing lance according to the invention is also specifically designed for extinguishing lithium-ion batteries installed in electric vehicles. This means that fire brigades now have an effective and completely safe fire extinguisher for use in applications involving burning objects with high voltages.

A large-surface impact plate at the operator-side end of the holding section can be provided to establish surface-level physical contact with an operator. A centrally mounted impact plate of this type ensures that the impact is as straight as possible in order to prevent the electric extinguishing lance from bending. In addition, a spacer section to the tubular extinguishing section can also be provided adjacent to the impact plate.

In an emergency, the electric extinguishing lance can be inserted into the battery of a burning electric vehicle, for example. Due to the tip in the front area, material that is in the way, such as a battery wall, can be easily penetrated. Such a high-strength but pointed nozzle prevents or at least minimizes wear and tear, making it easier to penetrate the surface of the object to be extinguished.

Flow-restricted nozzle(s) at the tip of the lance also ensure that sufficient extinguishing success can be achieved quickly and efficiently and, in particular, with a relatively small amount of extinguishing water.

There is currently no alternative way on the market to extinguish an electric vehicle battery directly and at the same time safely for the firefighter. In numerous tests, the factory fire brigades of well-known automobile manufacturers have hardly ever extinguished fires in electric vehicles without the electric extinguishing lance according to the invention, and if they have, then only with the use of extremely high Water and foam, but always without effective protection for the firefighter against high electrical voltages.

The situation is very similar when extinguishing fires caused by transformers or electrical generators, such as those used in photovoltaic systems.

Preferred embodiments of the invention

A particularly advantageous class of embodiments of the electric extinguishing lance according to the invention is characterized in that the voltage-insulating coating of the tubular extinguishing section has a layer thickness d ≥ 2mm, in particular between 2mm and 5mm, at least in the area of the holding section with handle part, and that the voltage-insulating coating of the handle part of the holding section and also of the extinguishing section is designed to be electrically insulating for electrical voltages U up to 1000V and above. The handle part itself can therefore now ensure sufficient protection of the operator against electrical voltages in the area of the holding section in conjunction with the tubular extinguishing section. Particularly preferred are developments of this class of embodiments which are characterized in that the voltage-insulating coating of the handle part and also of the extinguishing section is also designed for electrical voltages U ≥ 1000V.

In this context, it is advantageous if the voltage-insulating coating of the handle part as well as the extinguishing section already meets at least the minimum requirements of the European Standards 60903 and/or 659 for insulating protective gloves for working under electrical voltage are sufficient. It is also advantageous if the voltage-insulating coating of the handle part and the extinguishing section is made of heat-insulating, flame-resistant material - for example using aramid and/or para-aramid - and also meets the minimum requirements of European Standard 407 for protective gloves against thermal risks.

It is particularly advantageous if the voltage-insulating coating of the handle and the extinguishing section is made of polyvinyl chloride. This ensures a longer service life for the coating. Signs of aging are minimized.

Further particular advantages arise in designs in which the holding section under the stress-insulating coating of the handle part, and preferably also the tubular extinguishing section and its tip, are made of metal, preferably of VA steel, in particular of austenitic, acid-resistant 18/10 Cr-Ni steel. The tip of the tubular extinguishing section should be hardened. These materials are mechanically more resistant and chemically particularly resistant to battery acid, for example in an electric vehicle that is to be extinguished. This, as well as the above-mentioned preferred processing variant of the tip, contribute to increased mechanical and chemical resistance and thus to longer durability.

In a further class of advantageous embodiments of the electric fire extinguishing lance according to the invention, the handle part of the holding section has at least one bow handle with hand protection. This enables safe operation and good localization of the battery. Furthermore, the bow handle serves as protection against unwanted deformation of the lance when it is struck into the object to be extinguished.

The embodiments of this class can be further improved by further developments in which the handle part of the holding section has two handles for two-handed operation of the electric fire extinguishing lance. This ensures safe operation and localization in the object to be extinguished, into which the fire is to be penetrated. Further advantageous embodiments are characterized by the fact that an actuating valve is provided on the extinguishing agent supply for letting in or stopping the flow of extinguishing agent into the tubular extinguishing section and a trigger device for manually controlling the actuating valve is provided on the holding section, preferably on the handle part.

In the electric extinguishing lance according to the invention, the free end of the tubular extinguishing section is tapered. This enables a particularly straight and easy impact into the object to be extinguished.

According to the invention, the tip of the tubular extinguishing section has a maximum outer diameter that is between 1/3 and 3/4, preferably between 1/2 and 2/3, of the outer diameter of the tubular extinguishing section. In various electric vehicle models, the battery is installed almost on the entire base plate, but only about 4-5cm thick. The electric extinguishing lance is inserted into the battery through the base plate for extinguishing. With the previously known lance tip, however, there is a risk (and according to information from the factory fire departments of well-known vehicle manufacturers, this has already happened) that the lance tip will penetrate the battery. and the extinguishing agent is then not distributed in the burning battery in the correct way. The depth of impact is now limited by the new design of the tip proposed here in such a way that a clean penetration of the battery box is not possible or only possible with a great deal of additional force. Due to the now larger maximum external diameter of the tubular extinguishing section adjacent to the tip compared to the blunt conical end of the tip, there is noticeable and considerable mechanical resistance when the electric extinguishing lance is struck as soon as the tip has penetrated the battery.

According to the invention, a transition section is arranged between the conical, tapered free end and the adjoining tubular extinguishing section, which transition section is geometrically designed in such a way that it transfers the maximum outer diameter of the conical free end with a cone angle between 55° and 85°, preferably about 70°, to the full outer diameter of the tubular extinguishing section. This transition section ensures a noticeable increase in mechanical resistance when the extinguishing lance is struck into the object to be extinguished.

In practice, designs of these variants have proven to be effective in which a cylindrical intermediate section with an axial length L _ZA between 30mm and 80mm, preferably about 50mm, is arranged between the maximum outer diameter of the conical free end and the transition section, the diameter of which corresponds to the maximum outer diameter of the conical free end and which transfers the conical free end to the beginning of the transition section at its minimum outer diameter. The cylindrical intermediate section initially ensures a constant mechanical resistance when the fire extinguishing lance hits the object to be extinguished, before the transition section described above slows down the further advance of the fire extinguishing lance tip.

Designs in which the conically tapered free end of the tubular extinguishing section is manufactured in one piece with the transition section, if necessary also in one piece with the cylindrical intermediate section and the cylindrical connecting section, have also proven to be particularly inexpensive and easy to manufacture.

A class of embodiments in which the tapered free end of the tubular extinguishing section, and possibly also the transition section, the cylindrical intermediate section and the cylindrical connecting section, is designed as an exchangeable tip relative to the tubular extinguishing section is particularly preferred. This means that the electric extinguishing lance can also be used for other extinguishing agent variants. Furthermore, the tip can be quickly and easily replaced with another one if it becomes worn. Since a fire in a lithium-ion battery in an electric vehicle, for example, can cause temperatures of up to 1000°C, the increased wear on the tip may make it necessary to replace it.

Advantageous developments of this class of embodiments are characterized by the fact that various exchangeable tips, preferably with different geometries, diameters and in particular different materials, are available and can be kept in stock for a wide variety of purposes. This means that the electric fire extinguishing lance according to the invention can be quickly made ready for use again if it becomes worn. The tip can also be quickly replaced directly on site during use.

Further developments are also preferred in which the replaceable tip(s) is/are provided with a screw thread or a bayonet lock for detachable attachment to the tubular extinguishing section, with two holding points for wrenches for easy disassembly being provided. This means that the lance can be quickly made ready for use again if it becomes worn and the tip can also be quickly replaced in the event of an emergency.

Particularly practical are variants in which the cylindrical connection section and, if applicable, also the transition section have a chamfer as an attachment surface for a wrench for easy assembly and disassembly of the replaceable tip.

In a further class of advantageous embodiments of the electric fire extinguishing lance according to the invention, at least one nozzle for the discharge of pressurized liquid fire extinguishing agent is integrated into the tapered free end of the tubular fire extinguishing section, wherein the nozzle is preferably shaped in such a way that it optimally injects fire extinguishing agent into the burning object and/or distributes it over its surface. In this way, only comparatively small amounts of fire extinguishing agent are required.

In practice, further developments of this class of embodiments have proven successful, in which the nozzle has a clear diameter of between 30 mm and 40 mm, preferably about 33.7 mm, a length of between 25 mm and 50 mm, preferably about 30 mm, and a width of between 15 mm and 25 mm, preferably 21.3 mm. These special dimensions also have advantages in terms of production technology.

Finally, other advantageous developments of this class of embodiments are characterized by the fact that three nozzles are provided that are evenly distributed around the longitudinal axis of the tubular extinguishing section. This ensures that the extinguishing agent penetrates the object to be extinguished in a targeted and even manner during use.

In practice, a class of embodiments of the extinguishing lance according to the invention has proven particularly useful in which the holding section at the end facing the operator has an impact section in extension of the tubular extinguishing section, the end surface of which is designed as a large-area impact plate and has a larger outer diameter than the tubular extinguishing section, preferably between 1.5 times and 2.5 times the outer diameter of the tubular extinguishing section, in particular an outer diameter that is at least twice as large. The impact section is preferably made of solid material, in particular of metal, and is particularly preferably replaceable, in particular in the form of a striking mandrel that can be plugged or screwed onto the handle part in extension of the longitudinal axis of the tubular extinguishing section. This provides a sufficiently large area for introducing mechanical force in the direction of the longitudinal axis of the extinguishing lance, so that the lance can be driven quickly and precisely into the object to be extinguished.

Advantageous further developments of this class of embodiments are characterized in that the striking plate has a cylindrical shape with at least one, preferably two parallel, opposite bevel surfaces. With a striking head that is completely round in its circumference, the sledgehammer does not always hit in the middle, which Penetration of the electric extinguishing lance into the object to be extinguished is made more difficult. In extreme cases, the screw thread of an exchangeable impact head can be bent by the impact. In order to distribute the impact more evenly, it is therefore recommended to enlarge the thread slightly and remove the rounded areas from the impact head in the front and rear areas. This means that the operator always hits the impact head in the middle.

In order to ensure personal protection when extinguishing burning electric vehicles, the electric fire extinguishing lance according to the invention is designed with the electrical insulation described above in the handle area. In the highly unlikely event that the positive pole of the vehicle battery is electrically connected to the negative pole in the event of an accident, a conductive connection to earth potential should be established.

In addition or as an alternative, in further developments, a first earthing device for establishing an electrically conductive connection with the voltage potential of the earth can be provided on the impact section, preferably on the part of the impact section following the large-area impact plate in the axial direction of the tubular extinguishing section, which first earthing device comprises in particular an earthing screw and an earthing cable.

For these reasons, embodiments of the invention are also particularly preferred in which the coupling device for connecting a pressure hose for liquid extinguishing agent has a second earthing device for establishing an electrically conductive connection with the voltage potential of the earth, which in particular comprises an earthing nut and a second earthing cable.

Intensive fire tests have shown that, depending on the location and type of vehicle, faster extinguishing results can be achieved with electric fire extinguishing lances of varying lengths. There are very different scenarios, especially in the case of vehicle accidents. Sometimes there is very little space, in which case a short version makes sense. Sometimes the lance has to be inserted through a side window and through the vehicle floor, in which case the rescue workers need the extension.

Therefore, embodiments in which the extinguishing lance, in particular the impact section, is designed to be divisible are particularly advantageous. This means that the extinguishing lance according to the invention can be used particularly flexibly, for example when a vehicle catches fire in your own garage or in a parking garage. In this context, cases of spontaneous combustion of lithium-ion batteries have been reported, which have led to fires in buildings and considerable damage.

In favorable further developments, the extinguishing lance is designed to be extendable along its longitudinal axis, with the impact plate of the impact section at the end facing the operator being arranged at a variable distance from the tubular extinguishing section. This design makes the extinguishing lance particularly suitable for use with trucks and other large vehicles.

Preferably, the tubular extinguishing section is also designed to be extendable, in particular by means of one or more tubular extension pieces which have the same outer diameter as the tubular extinguishing section. This also achieves greater flexibility in use.

Further features and advantages of the invention emerge from the following detailed description of an embodiment of the invention based on the figure of the drawing, which shows details essential to the invention, and from the claims. The individual features can be implemented individually or in groups in any combination in variants of the invention. The embodiments shown and described are not to be understood as an exhaustive list, but rather are exemplary in nature for the description of the invention.

Detailed description of the invention and drawing

Fig. 1a

eine schematische Seitenansicht einer ersten Ausführungsform der erfindungsgemäßen E-Löschlanze mit spannungsisolierender Beschichtung des rohrförmigen Löschabschnitts im Bereich des Haltegriffs;

Fig. 1b

die Ausführungsform von Fig. 1a in einer teilweise transparenten Ansicht von oben in Richtung der Achse des rohrförmigen Löschabschnitts;

Fig. 2a

Detailansicht einer weiteren Ausführungsform der erfindungsgemäßen E-Löschlanze im Bereich des Haltegriffs mit zum rohrförmigen Löschabschnitt verlaufenden Bügeln sowie mit Flügelmutter an der Ankoppelvorrichtung für Löschwasser;

Fig. 2b

die Ausführungsform von Fig. 2a in einer vertikalen Längsschnittansicht von der Seite;

Fig. 2c

Detail Z aus Fig. 2b mit einer Aufnahme für eine Einschweißbuchse am rohrförmigen Löschabschnitt;

Fig. 3a

eine schematische räumliche Darstellung eines Schlagdorns mit rückseitiger Schlagplatte, Fasenfläche und Erdungsschraube zum Aufbringen auf das Griffteil in Verlängerung der Längsachse des rohrförmigen Löschabschnitts;

Fig. 3b

eine Seitenansicht auf die Ausführungsform von Fig. 3a mit Blick auf die Fasenfläche;

Fig. 3c

die Seitenansicht von Fig. 3b um 90° um die Längsachse gedreht mit Blick auf die Erdungsschraube;

Fig. 4a

eine schematische räumliche Darstellung einer austauschbaren Spitze des rohrförmigen Löschabschnitts;

Fig. 4b

eine schematische Seitenansicht der Spitze nach Fig. 4a mit Blick auf eine der beiden gegenüberliegenden Fasenflächen;

Fig. 4c

die Ausführungsform von Fig. 4b um 90° um die Längsachse der Spitze gedreht mit Blick jeweils von der Seite auf beide einander gegenüberliegenden Fasenflächen;

Fig. 4d

die Ausführungsform der Spitze von Fig. 4c in einem vertikalen Längsschnitt;

Fig. 4e

die Düsenverteilung der Spitze von Fig. 4c im vergrößerten Detail mit Blickrichtung parallel zur Längsachse der Spitze;

Fig. 5a

ein Verlängerungsstück zur Verlängerung der axialen Länge des rohrförmigen Löschabschnitts in einem vertikalen Längsschnitt;

Fig. 5b

eine Seitenansicht des Verlängerungsstücks aus Fig. 5a in Blickrichtung senkrecht zur Längsachse mit jeweils einer Einschweißbuchse an beiden Enden zum Einbau des Verlängerungsstücks in den rohrförmigen Löschabschnitt;

Fig. 5c

eine vergrößerte Seitenansicht der linken Einschweißbuchse des Verlängerungsstücks aus Fig. 5b;

Fig. 5d

die Einschweißbuchse aus Fig. 5c in einem vertikalen Längsschnitt;

Fig. 5e

eine vergrößerte Seitenansicht der rechten Einschweißbuchse des Verlängerungsstücks aus Fig. 5b in einem vertikalen Längsschnitt; und

Fig. 5f

die Einschweißbuchse aus Fig. 5e mit Blickrichtung parallel zur Längsachse der rechten Einschweißbuchse.

The invention is illustrated in the - essentially rather schematic - figures of the drawing and is explained in more detail using an exemplary embodiment. They show:

Fig. 1a

a schematic side view of a first embodiment of the electric extinguishing lance according to the invention with a voltage-insulating coating of the tubular extinguishing section in the region of the handle;

Fig. 1b

the embodiment of Fig. 1a in a partially transparent view from above in the direction of the axis of the tubular extinguishing section;

Fig. 2a

Detailed view of a further embodiment of the electric fire extinguishing lance according to the invention in the area of the handle with brackets running to the tubular fire extinguishing section and with wing nut on the coupling device for fire extinguishing water;

Fig. 2b

the embodiment of Fig. 2a in a vertical longitudinal sectional view from the side;

Fig. 2c

Detail Z from Fig. 2b with a holder for a weld-in bushing on the tubular extinguishing section;

Fig. 3a

a schematic spatial representation of a striking mandrel with rear striking plate, bevelled surface and grounding screw for attachment to the handle part in extension of the longitudinal axis of the tubular extinguishing section;

Fig. 3b

a side view of the embodiment of Fig. 3a with a view of the chamfer surface;

Fig. 3c

the side view of Fig. 3b rotated by 90° around the longitudinal axis with a view towards the earthing screw;

Fig. 4a

a schematic spatial representation of a replaceable tip of the tubular extinguishing section;

Fig. 4b

a schematic side view of the tip after Fig. 4a looking at one of the two opposite bevel surfaces;

Fig. 4c

the embodiment of Fig. 4b rotated by 90° around the longitudinal axis of the tip, viewed from the side onto both opposite bevel surfaces;

Fig. 4d

the design of the tip of Fig. 4c in a vertical longitudinal section;

Fig. 4e

the nozzle distribution of the tip of Fig. 4c in enlarged detail with view parallel to the longitudinal axis of the tip;

Fig. 5a

an extension piece for extending the axial length of the tubular extinguishing section in a vertical longitudinal section;

Fig. 5b

a side view of the extension piece Fig. 5a in the direction of view perpendicular to the longitudinal axis with a welded bushing at each end for installation of the extension piece in the tubular extinguishing section;

Fig. 5c

an enlarged side view of the left weld-in bushing of the extension piece from Fig. 5b ;

Fig. 5d

the weld-in bushing Fig. 5c in a vertical longitudinal section;

Fig. 5e

an enlarged side view of the right weld-in bushing of the extension piece from Fig. 5b in a vertical longitudinal section; and

Fig. 5f

the weld-in bushing Fig. 5e with a view parallel to the longitudinal axis of the right weld-in bushing.

In the Figures 1a and 1b The drawing shows an embodiment of the electrically insulating E-extinguishing lance 10 according to the invention for extinguishing burning objects under electrical voltage. As already shown in the patent application filed by the applicant itself, Like the extinguishing lance known from the prior art, the electric extinguishing lance 10 according to the invention also has a holding section with a handle 11 for an operator, an extinguishing agent supply with a coupling device 12 for connecting a pressure hose for liquid extinguishing agent, and a tubular extinguishing section 13 connected to the holding section and optionally the coupling device 12 , from the free end of which extinguishing agent can be introduced into a burning object under pressure. The handle 11 of the holding section has a voltage-insulating coating 11a , which is designed to be electrically insulating even for electrical voltages U ≥ 500V, the tubular extinguishing section 13 being geometrically tapered at its free end and having a narrowed clear flow cross-section for the extinguishing agent passed through under pressure.

Compared to such an above-mentioned known, older extinguishing lance of the applicant, the electric extinguishing lance 10 according to the invention is characterized in that the tubular extinguishing section 13 now also has, at least in the region of the holding section with handle part 11, a voltage-insulating coating 13a which is designed to be electrically insulating for electrical voltages U ≥ 500V.

In particular, this voltage-insulating coating 13a of the tubular extinguishing section 13 can have a layer thickness d ≥ 2mm, in particular between 2mm and 5mm, at least in the region of the holding section with handle part 11, and the voltage-insulating coating 11a of the handle part 11 of the holding section as well as the coating 13a of the extinguishing section 13 can even be electrically insulating for electrical voltages U up to 1000V and above.

Furthermore, the tubular extinguishing section 13 can be made of VA steel, in particular of austenitic, acid-resistant 18/10 Cr-Ni steel, and the stress-insulating coating 13a of the tubular extinguishing section 13 can be made of polyvinyl chloride.

In the Figures 1a and 1b In the embodiment shown, the handle part 11 of the holding section has two handles 11', 11" for two-handed operation of the electric fire extinguishing lance 10.

The electric extinguishing lance 10 according to the invention can have an actuating valve (not shown) on the extinguishing agent supply for admitting or stopping an extinguishing agent flow into the tubular extinguishing section 13 and a trigger device on the holding section, preferably on the handle part 11, for manually controlling this actuating valve.

Furthermore, the Fig. 1a The embodiment of the electric extinguishing lance 10 according to the invention shown has a preferably replaceable impact section 14 at the end facing the operator, adjacent to the holding section, in extension to the tubular extinguishing section 13, which serves to introduce impact force in the direction of the longitudinal axis of the electric extinguishing lance 10 in order to drive it into an object to be extinguished. On the side remote from the operator, the free end of the electric extinguishing lance 10 is designed as a preferably also replaceable and specially hardened tip 15 .

The Figures 2a to 2c show in enlarged detail the area around the holding section with handle part 11, extinguishing agent supply with the coupling device 12 for connecting a pressure hose for liquid extinguishing agent, as well as the tubular extinguishing section 13 adjoining the holding section and the coupling device 12.

The coupling device 12 has a grounding device for establishing an electrically conductive connection with the electrical potential of the earth, which in the embodiment shown comprises a grounding nut 12‴ and a grounding cable (not specifically shown in the drawing).

In addition, a welded bushing 13' is provided in the axial connection to the tubular extinguishing section 13, which enables an extension of the electric extinguishing lance 10 according to the invention, as shown below with reference to the Figures 5a-f explained in more detail.

The Figures 3a to 3c show in enlarged detail a mandrel 16 that can be attached or screwed onto the holding section of the electric extinguishing lance 10, more precisely onto the handle part 11 in the extension of the longitudinal axis of the tubular extinguishing section 13, which here forms the striking section 14. Its end surface on the operator side is designed as a large-area striking plate 14' and has a larger outer diameter than the tubular extinguishing section 13, preferably between 1.5 times and 2.5 times the outer diameter of the tubular extinguishing section 13. The mandrel 16 is preferably made of solid material, in particular of metal.

In this embodiment, the striking plate 14' has a cylindrical end with a large striking surface on the operator side. In addition, two parallel, opposite beveled surfaces 14" are provided here, which can serve as attachment surfaces for tools for easier assembly and disassembly of the striking mandrel 16 on the handle part 11. Furthermore, a grounding device for establishing an electrically conductive connection with the voltage potential of the earth is provided, which here comprises a grounding screw 14‴ and a grounding cable (not specifically shown in the drawing).

The striking pin 16 can be attached to the handle part 11, for example, by screwing it on or by plugging it on, for example by means of a bayonet lock.

The Figures 4a to 4e show in enlarged detail the tapered free end of the electric extinguishing lance 10 according to the invention, which in this embodiment is designed as an exchangeable, conically tapered tip 15, wherein different exchangeable tips 15, preferably with different geometries, diameters and in particular made of different materials with different material properties, can be provided for different purposes.

Particularly preferably, the conically tapered free end of the electric extinguishing lance 10 according to the invention has a maximum outer diameter which is between 1/3 and 3/4, preferably between 1/2 and 2/3, of the outer diameter of the tubular extinguishing section 13.

In the tapered free end of the tubular extinguishing section 13, as a rule at least one, preferably three evenly spaced distributed around the longitudinal axis of the tubular extinguishing section 13 (see in particular Fig. 4e ) arranged nozzles 17 for the discharge of pressurized liquid extinguishing agent can be integrated, wherein the nozzles are preferably shaped such that they optimally inject extinguishing agent into the burning object and/or distribute it over its surface.

Between the conically tapered free end and the adjoining tubular extinguishing section 13, a transition section 18 is arranged, which is geometrically designed such that it transfers the maximum outer diameter of the conical free end with a cone angle between 55° and 85°, in the embodiment shown approximately 70°, to the full outer diameter of the tubular extinguishing section 13.

Between the maximum outer diameter of the conical free end and the transition section 18 there is arranged a cylindrical intermediate section 19 with an axial length L _ZA between 30 mm and 80 mm, preferably about 50 mm, whose diameter corresponds to the maximum outer diameter of the conical free end and which transfers the conical free end to the beginning of the transition section 18 at its minimum outer diameter.

When the electric fire extinguishing lance 10 according to the invention is struck with the tip 15 into a solid object to be extinguished, often an electric battery, the tip initially penetrates quickly into the object up to the operator-side end of the cylindrical intermediate section 19. However, the transition section 18 then ensures increasing mechanical resistance. As a result, the operating firefighter notices that the tip 15 now extends over a little more than the length of the conical end piece and the cylindrical intermediate section 19 has penetrated the object. At this moment, it will therefore quickly stop the power supply to the impact section 14 in order not to completely penetrate the object and then land with the extinguishing tip and nozzles 17 outside the object, which would make effective extinguishing significantly more difficult or even impossible.

In the embodiment shown, a cylindrical connecting section 20 with an axial length L _AA of between 10 mm and 30 mm, preferably approximately 20 mm, is arranged between the maximum outer diameter of the transition section 18 and the beginning of the tubular extinguishing section 13, the diameter of which corresponds to the outer diameter of the tubular extinguishing section 13 and which transfers the transition section 18 to the beginning of the tubular extinguishing section 13.

The cylindrical connection section 20 and possibly also a small part of the transition section 18 has two opposite bevels 21 , which can serve as starting surfaces for a wrench to facilitate assembly and disassembly of the replaceable tip 15.

The replaceable tip 15 can be provided with a screw thread (not shown in the drawing) or a bayonet lock for releasable attachment to the tubular extinguishing section 13.

The Figures 5a to 5f show, partly in enlarged detail, auxiliary devices for the axial extension of the electric extinguishing lance 10 according to the invention with respect to its longitudinal axis.

For this purpose, the tubular extinguishing section 13 can itself be designed to be extendible, in particular by means of one or more tubular extension pieces 22, as shown in the Figures 5a and 5b and which have the same outer diameter as the operator-side first part of the tubular extinguishing section 13.

In order to mount an extension piece 22 in the tubular extinguishing section 13, connection means are provided at one or both axial ends of the extension piece 22 in the embodiments shown.

In the Figures 5e and 5f A first weld-in bushing 13' is shown in detail, which is also already in the Figures 1a , 2a and 2b can be seen. In the Fig. 5b In the extension piece 22 shown, this first weld-in bushing 13' is arranged at the right end of the extension piece 22.

Another weld-in bushing 22' at the left end of the Fig. 5b The extension piece 22 shown is shown in greater detail in the Figures 5c and 5d shown.

Additionally or alternatively, the large-surface impact plate 14' of the impact section 14 can be arranged at the operator-side end of the holding section at a variable distance from the tubular extinguishing section 13.

List of reference symbols

10

Fire extinguishing lance

11

Handle part

11', 11"

Handlebar grips

11a

Voltage-insulating coating on the handle

12

Coupling device

12‴

Grounding nut

13

tubular extinguishing section

13a

Voltage-insulating coating of the tubular extinguishing section

13'

first welded bushing in the tubular extinguishing section

14

Impact section

14'

Strike plate

14"

Chamfered surfaces

14‴

Ground screw

15

Tip of the tubular extinguishing section

16

Punch

17

Nozzles

18

Transition section

19

Intermediate section

20

Connection section

21

chamfer

22

Extension piece

22'

additional welded bushing in the extension piece

Claims (15)

1. Extinguishing lance (10) for extinguishing electric devices that are burning, such as vehicles equipped with an electric motor, the extinguishing lance (10) comprising a holding portion having a handle part (11) for an operator, an extinguishing agent feed having a coupling device (12) for connecting a pressure hose for liquid extinguishing agent, and a tubular extinguishing portion (13) adjoining the holding portion and, optionally, the coupling device (12), from the free end of which extinguishing portion extinguishing agent can be introduced under pressure into a burning object, the handle part (11) of the holding portion having a voltage-insulating coating (11a) which is designed so as to be electrically insulating even for electric voltages U ≥ 500 V, the tubular extinguishing portion (13) being made of a material which has such a high tensile strength R_m that it withstands a mechanical stress σ ≥ 500 N/mm², and which has a melting temperature t_s ≥ 650°C, the tubular extinguishing portion (13) being designed so as to taper geometrically at its free end and having a constricted, hollow flow cross-section for the extinguishing agent conducted through under pressure, the tubular extinguishing portion (13) and also the tapering free end of the tubular extinguishing portion (13) being made of stainless steel, and the tapering free end of the tubular extinguishing portion (13) additionally being hardened,
   characterized in that

   the tubular extinguishing portion (13) also has, at least in the region of the holding portion, a voltage-insulating coating (13a) outside the grip part (11), which coating is designed to be electrically insulating for electrical voltages U ≥ 500 V, in that the free end of the tubular extinguishing portion (13) is designed to taper conically and has a maximum outer diameter which is between 1/3 and 3/4 of the outer diameter of the tubular extinguishing portion (13),

   and in that a transition portion (18) is arranged between the conically tapering free end and the adjoining tubular extinguishing portion (13), which transition portion is geometrically designed such that it transfers the maximum outer diameter of the conical free end at a cone angle of between 55° and 85° to the full outer diameter of the tubular extinguishing portion (13).
2. Extinguishing lance according to claim 1, characterized in that the voltage-insulating coating (13a) of the tubular extinguishing portion (13) has a layer thickness d ≥ 2 mm, and in particular between 2 mm and 5 mm, at least in the region of the holding portion with the handle part (11), and in that the voltage-insulating coating (11a) of the handle part (11) of the holding portion and also the coating (13a) of the extinguishing portion (13) are designed to be electrically insulating for electric voltages U up to 1,000 V and above.
3. Extinguishing lance according to either claim 1 or claim 2, characterized in that the tubular extinguishing portion (13) is made of VA steel, and in particular austenitic, acid-resistant 18/10 Cr-Ni steel, and the voltage-insulating coating (13a) of the tubular extinguishing portion (13) is made of polyvinyl chloride.
4. Extinguishing lance according to any of the preceding claims, characterized in that the free end of the tubular extinguishing portion (13) has a maximum outer diameter that is between 1/2 and 2/3 of the outer diameter of the tubular extinguishing portion (13).
5. Extinguishing lance according to claim 4, characterized in that the transition portion (18) is geometrically designed such that it transfers the maximum outer diameter of the conical free end at a cone angle of approximately 70° to the full outer diameter of the tubular extinguishing portion (13).
6. Extinguishing lance according to claim 5, characterized in that, between the maximum outer diameter of the conical free end and the transition portion (18), a cylindrical intermediate portion (19) having an axial length L_ZA of between 30 mm and 80 mm, and preferably approximately 50 mm, is arranged, the diameter of which intermediate portion corresponds to the maximum outer diameter of the conical free end and which intermediate portion transfers the conical free end to the beginning of the transition portion (18) at the minimum outer diameter thereof.
7. Extinguishing lance according to either claim 5 or claim 6, characterized in that a cylindrical connecting portion (20) having the axial length L_AA of between 10 mm and 30 mm, and preferably approximately 20 mm, is arranged between the maximum outer diameter of the transition portion (18) and the beginning of the tubular extinguishing portion (13), the diameter of which connecting portion corresponds to the outer diameter of the tubular extinguishing portion (13) and which connecting portion transfers the transition portion (18) to the beginning of the tubular extinguishing portion (13).
8. Extinguishing lance according to any of claims 5 to 7,
   characterized in that the conically tapering free end of the tubular extinguishing portion (13) is formed in one piece with the transition portion (18), and optionally also in one piece with the cylindrical intermediate portion (19) and the cylindrical connecting portion (20).
9. Extinguishing lance according to any of claims 4 to 8,
   characterized in that the conically tapering free end of the tubular extinguishing portion (13), and optionally also the transition portion (18), the cylindrical intermediate portion (19), and the cylindrical connecting portion (20), is designed as an exchangeable tip (15) with respect to the tubular extinguishing portion (13) and is preferably provided with a screw thread or a bayonet lock for releasable fastening to the tubular extinguishing portion (13).
10. Extinguishing lance according to claims 8 and 9, characterized in that the cylindrical connecting portion (20), and optionally also the transition portion (18), has a chamfer (21) as an attachment surface for a wrench for easy assembly and disassembly of the exchangeable tip (15).
11. Extinguishing lance according to any of the preceding claims, characterized in that the holding portion has, at the operator-side end, a striking portion (14) in extension of the tubular extinguishing portion (13), the operator-side end surface of which striking portion is designed as a striking plate (14') having a large surface area and has a larger outer diameter than the tubular extinguishing portion (13), preferably between 1.5 times and 2.5 times the outer diameter of the tubular extinguishing portion (13), and in particular an outer diameter at least twice as large, and in that the striking portion (14) is made of solid material, in particular of metal, and is preferably designed so as to be exchangeable, in particular in the form of a striking pin (16) which can be plugged or screwed onto the handle part (11) in extension of the longitudinal axis of the tubular extinguishing portion (13).
12. Extinguishing lance according to claim 11, characterized in that the striking plate (14') has a cylindrical shape having at least one, and preferably two, chamfer surfaces (14") located opposite one another in parallel.
13. Extinguishing lance according to either claim 11 or claim 12, characterized in that a first grounding device for establishing an electrically conductive connection to a voltage potential of the ground is present on the striking portion (14), preferably on the part of the striking portion (14) following the large-surface-area striking plate (14') in the axial direction of the tubular extinguishing portion (13), which grounding device in particular comprises a grounding screw (14‴) and a grounding cable.
14. Extinguishing lance according to any of the preceding claims, characterized in that the coupling device (12) for connecting a pressure hose for liquid extinguishing agent has a second grounding device for establishing an electrically conductive connection with the voltage potential of the ground, which grounding device in particular comprises a grounding nut (12‴) and a second grounding cable.
15. Extinguishing lance according to any of the preceding claims, characterized in that the extinguishing lance (10) is designed to be extendable with respect to its longitudinal axis, in particular the large-surface-area striking plate (14') of the striking portion (14) being arranged at the operator-side end of the holding portion at a variable distance from the tubular extinguishing portion (13), and/or the tubular extinguishing portion (13) in turn being designed to be extendable, in particular by means of one or more tubular extension pieces (22) which have the same outer diameter as the tubular extinguishing portion (13).

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