DE102024116496A1 - Device for reducing thermal stress and regulating the microclimate in a protective helmet and protective helmet equipped with the device - Google Patents

Abstract

The invention relates to a device for reducing thermal stress and regulating the microclimate in a protective helmet (H), wherein at least one capsule arrangement (3, 4) with phase change material (PCM) is integrated into a helmet shell (1) of the protective helmet (H) and/or a pressurized gas line (5) leads to the helmet shell (1), with which expansion cooling by means of a cooling gas inside the protective helmet (H) can be achieved. The invention further relates to a protective helmet equipped with the device.

Description

The invention relates to a device for reducing thermal stresses and regulating the microclimate in a protective helmet and a protective helmet equipped with the device, according to the preamble of the first and eleventh claims.

It is well known that high ambient temperatures and/or high humidity, combined with physical exertion, quickly reduce a person's comfort level and performance. In such situations, perspiration and its evaporation are meant to lead to the body's natural thermoregulation, maintaining a core body temperature of approximately 37°C. If the body is unable to regulate its temperature with the necessary intensity, fatigue can quickly set in, potentially leading to life-threatening changes in vital signs.

Several methods are already known from the prior art to counteract thermal loads on the body and ensure more comfortable temperatures. These solutions target both protective helmets and outerwear, as described in the publication. EP 1 653 818 A4 described, as well as according to DE 10 2010 020 262 B4 This is geared towards medical applications. The solution predominantly used is encapsulated phase change materials (PCMs). The heat generated causes the PCM to melt at a nearly constant temperature, instead of increasing the ambient temperature near the body.

The printed publication continues with further information. DE 10 2016 201 912 B4 It has been proposed to equip the PCM in a helmet with an additional heat pipe that actively transfers the body heat absorbed by the PCM to the outer, heat-emitting side of the helmet in the described application. This active heat dissipation is expected to result in a prolonged cooling effect of the PCM.

In the case of one in the printed text WO2016/135529 A1 In the presented protective helmet with temperature regulation device, the PCM is used as a heat-absorbing cushion in conjunction with forced ventilation of the helmet. The aim is to extract heat from the warm ambient air drawn in by the PCM, thus generating a cooling circulation around the head.

Instead of PCM, the printed text uses... DE 197 56 470 A1 The use of Peltier elements for cooling bicycle helmets is an application, whereby the power supply is to be ensured via batteries or solar cells.

However, the known solutions in the prior art have disadvantages. For example, the use of PCM is limited, particularly in the area of head protection, due to the additional weight that must be applied. In helmets or similar devices, even a few hundred grams of additional weight can significantly impair comfort and performance. Furthermore, the cooling of warm ambient air by PCM for a cooling circulation, as described in the publication, is not feasible. EP 3 261 473 A4 This is only possible for moderate ambient temperatures below 50 °C, as only a limited amount of heat can be extracted from the air during airflow due to the laws of heat transfer (heat transfer coefficient, driving temperature difference, heat transfer surface area). Furthermore, it is essential to ensure that the ambient air flowing into the helmet is free of pollutants, which cannot generally be assumed.

Such solutions are therefore particularly unsuitable for protective helmets for rescue workers due to the hot and toxic gases produced during firefighting. The proposed technologies of the heat pipe and the Peltier element, including the power supply, are also considered unsuitable due to the additional weight.

The printed matter EP 2 249 672 B1 This describes a brain cooling device that utilizes an endothermic reaction for cooling. The device is particularly suitable for use in motorcycle helmets. It features an inner and outer layer located inside the helmet, separated by a membrane. An impact, or an impending impact, breaches this membrane and triggers the reaction. For example, water can be placed in the outer layer, which, upon impact, flows into the inner layer and initiates the reaction.

Furthermore, state-of-the-art solutions are purely measures to reduce the temperature near the body through the latent storage or dissipation of the generated heat. However, for optimal comfort and to maintain the body's natural thermoregulation, a dry microclimate near the body is essential. A particular problem in this regard is that air can hold less moisture as temperatures decrease. Consequently, a humid microclimate arises. rather something that inhibits natural thermoregulation and reduces wearing comfort.

From the printed text WO 2011/098761 A1 An expansion cooling system is known for use in a protective helmet, particularly a motorcycle helmet, wherein the helmet has a gas cartridge and porous channels or a porous membrane running inside the helmet. The gas is released by means of a switch or thermostatically.

Another known cooling device involves gas expansion, in which the gas is released from a pressure vessel. With the disclosed device, cooling is only possible in the event of a fall and not during activities aimed at regulating the microclimate. The device serves to cool injuries caused by impact and to reduce swelling in the head area.

The object of the invention is to provide a device for reducing thermal stress and regulating the microclimate in a protective helmet for rescue workers and a protective helmet equipped therewith, which has a simple structural design and prevents or reduces increased temperatures and humidity inside the protective equipment as a result of the thermal loads occurring, thus ensuring a more comfortable microclimate with the aim of ensuring a comfortable microclimate inside the protective helmet, at least for an extended period of time, which increases wearing comfort and enables natural thermoregulation, thereby delaying the decline in conductivity, maintaining core body temperature, extending the operating time and reducing the regeneration times, especially of rescue workers.

In this context, it is essential to reduce the external heat input into the interior of the protective equipment during heat exposure (e.g., in case of fire). Furthermore, the body's own heat loss and the moisture generated by the wearer's perspiration must be dissipated from the interior of the protective equipment to maintain natural thermoregulation and thus extend the wearer's performance and operational time, particularly for rescue workers.

This problem is solved by the features of the first and eleventh patent claims.

Advantageous embodiments result from the dependent claims.

According to the invention, the device for reducing thermal stresses and regulating the microclimate in a protective helmet comprises at least one capsule arrangement with phase change material (PCM) and/or at least one pressurized gas line leading to or into the helmet shell, with which expansion cooling by means of a cooling gas inside the protective helmet (H) can be realized.

This makes it possible, especially at high temperatures such as in the event of a fire, to lower the temperature inside the helmet and create a microclimate within the helmet which allows for a longer wearing time and thus a longer operating time even at high temperatures, better protecting the emergency personnel and/or reducing the thermal load while maintaining the same operating time in order to enable a shorter regeneration time after the operation.

Well-known protective helmets feature a so-called helmet liner and a helmet spider, which protect the wearer against external mechanical stresses.

According to the invention, at least one first capsule arrangement with PCM material is arranged in the helmet insert of the protective helmet.

This first capsule arrangement can be designed in one or more parts and already causes a temperature reduction inside the protective helmet, e.g. in case of fire.

Alternatively or additionally, at least one second capsule assembly can be arranged or attached to the head spider of the protective helmet. This second capsule assembly can also be designed as a single unit or in multiple parts.

The first capsule arrangement, preferably integrated into the helmet insert in the upper area of the protective helmet, particularly reduces the external heat input into the helmet interior.

The second capsule arrangement, located on the interior in the form of the head spider and situated directly in the area or circumference of the head, advantageously absorbs the body heat emitted via the head.

• - wenigstens eine perforierte Druckgasleitung und/oder
• - wenigstens ein Düsenkopf und/oder
• - wenigstens eine Luftdüse

anschließen, über welche das über die Druckgasleitung zugeführte Kühlgas in den Helm strömt und in dem Helm verteilt wird.Furthermore, it is possible that the pressurized gas line, which leads to or into the helmet shell of the protective helmet,

• - at least one perforated pressurized gas line and/or
• - at least one nozzle head and/or
• - at least one air nozzle

connect, through which the cooling gas supplied via the pressurized gas line flows into the helmet and is distributed within the helmet.

For example, it is possible to arrange the perforated compressed gas line and/or the nozzle head and/or the air nozzle on the head spider or to combine them with the first or second capsule arrangement.

The nozzle head is preferably attached to the inside of the helmet shell or to the head spider.

Advantageously, the first and/or second capsule arrangement serves as a heat storage medium.

The first capsule assembly and/or the second capsule assembly can consist of individual parts.

The first and/or second capsule assembly, or its individual components, each have a filling opening for the phase change material (PCM) and a venting opening. The phase change material is filled into the hollow capsule assemblies or components through the filling opening, while the air can escape through the venting opening.

After the capsule assemblies are filled with PCM material, the filling opening and the venting opening are tightly sealed.

The solution according to the invention thus consists, for the first time, of a device for rinsing the helmet interior with an expanding gas (expansion cooling) and/or encapsulated phase-change materials attached to the inner helmet shell, whereby both devices can be applied and used alone or in combination. For rinsing the helmet interior, a compressed gas is expanded from a pressure vessel, guided into the helmet interior via a hose system, and distributed in a targeted manner via perforated hoses. The incoming gas displaces the warm and humid air from the helmet interior into the ambient atmosphere. Since gases are known to have low humidity and are also supercooled after expansion, this ensures the desired microclimate inside the helmet. Consequently, the evaporation of sweat necessary for natural thermoregulation can occur, as the dry gas absorbs and carries away the moisture via diffusion and/or convection processes. For appropriate metering of the gas purge, the expansion cooling can be controlled and regulated (manually or automatically) via throttle and shut-off valves.

To minimize external heat input and internal heat load (body heat), particularly in extreme heat exposure, such as during fires, the invention utilizes a phase change material (PCM) on the inside of the helmet shell. The PCM is capable of storing heat at a nearly constant temperature during the phase change (typically from solid to liquid). As a result, the ambient temperature (in this case, the inside of the helmet) of the PCM only increases after the entire PCM has melted. Depending on the application, melting temperatures between 35 and 65 °C are suitable for use in protective helmets. To ensure that the PCM remains locally bound even in the liquid phase, it must be encapsulated. According to the invention, this can be achieved using 3D-printed hollow plastic bodies, deep-drawn and bonded plastic sheets, welded aluminum composite foils, or similar materials. In addition to heat storage, the poor thermal conductivity of paraffin-containing PCMs, in particular, dampens the heat introduced into the helmet interior from the outside, thus reducing the external heat load.

Compared to the prior art, the presented solution offers the advantage of enabling natural thermoregulation by generating and maintaining a cool, dry microclimate inside the helmet, thus allowing for longer operating times and improved performance for the helmet wearer. Accordingly, the invention allows not only the temperature but also the humidity inside the helmet to be regulated. This is made possible in particular by a combination of expansion cooling and PCM, resulting in the following specific advantages over the prior art.

During expansion cooling, supercooled and very dry expanding gas is introduced into the helmet, displacing the warm, humid air inside. This also prevents potentially toxic, warm, and humid ambient air from entering the helmet interior by actively introducing the expanded gas. The amount of expanding gas can be precisely regulated by adjusting the dosage via throttle and shut-off valves. Simultaneously with expansion cooling, the PCM capsule(s) located within the helmet dampen external heat loads (e.g., during firefighting operations) due to their low thermal conductivity and heat storage capacity (during phase changes), which are preferably positioned close to the helmet shell.

Due to the high heat storage capacity of the PCM capsule(s) placed directly on the head of the helmet wearer during the phase change The absorption of internal heat loads (body heat) ensures that almost constant temperatures inside the helmet can be maintained even at very high ambient temperatures.

Besides breathing air, technical gases such as _N₂ , _CO₂ , He, Ne, Ar, Kr, and Xe can be used to purge the helmet. Generally, all non-toxic, non-flammable, and inert gases can be used.

When flowing into the helmet, the expanding gas should have a temperature between 5-40 °C, especially between the head and the space of the protective helmet surrounding the head.

The relative humidity of the expanding gas as it flows into the helmet should preferably be between 5-25% relative humidity.

Preferably, the gas is supplied from a pressurized gas cylinder via a hose and released into the interior of the helmet through perforations in the hose. Alternatively, the gas can also be directed into the helmet, preferably into the upper region of the helmet, via a flat nozzle with a plurality of outlet openings.

Another option is the arrangement of a largely surface-shaped air distribution system with multiple outlet openings, located in the upper area of the protective helmet and connected to the pressurized gas cylinder via a hose. Such an air distribution system can also be integrated into a PCM capsule.

The PCM capsules are preferably made of plastic, for example TPU (thermoplastic polyurethane), PC (polycarbonate), PA (polyamide), PP (polypropylene), PE (polyethylene), PVC (polyvinyl chloride).

In particular, all printable, moldable, and blow-moldable plastics can be used for the PCM capsules, but also capsules made of aluminum composite foil.

The PCM capsules can, for example, be designed as a shell-shaped hollow body made of two deep-drawn polycarbonate shells, which are connected to each other at the edges and into whose cavity the PCM material has been introduced.

It is preferred that protective helmets be manufactured in series using the device according to the invention.

However, it is also possible to retrofit a commercially available protective helmet with the device according to the invention.

• 1 Prinzipskizze einer Ausstattung eines Schutzhelms z.B. für Feuerwehreinsatzkräfte,
• 2 Seitenansicht einer ersten PCM-Kapsel für einen Schutzhelm
• 3 Längsschnitt A-A gemäß 2,
• 4 Einzelheit B gemäß 3,
• 5 Darstellung einer von vier einzelnen ersten Kapseln 3.1, in zwei unterschiedlichen Ansichten,
• 6 Ansicht eines Helmeinlegers 2 aus Richtung seiner offenen Seite mit vier ersten Kapseln 3.1,
• 7 Schnitt C-C gemäß 6,
• 8 Darstellung einer Helmspinne 7 mit vier daran befestigten zweiten Kapseln 4.1,
• 9 Darstellung einer zweiten Kapsel 4.1 aus Richtung der Innenseite des Helms (Vorderansicht),
• 10 Vorderansicht einer zweiten Kapsel 4.1,
• 11 beispielhafte schematische Darstellung einer perforierten Druckgasleitung 4 für die Zuführung von Kühlgas,
• 12 dreidimensionale Darstellung einer ersten Ausführung eines Düsenkopfes für einen Schutzhelm,
• 13 Längsschnitt durch einen Düsenkopf 4.2 gem. 12,
• 14 Ausschnitt einer Kopfspinne 6 mit einem daran befestigten Düsenkopf 4.2 in einer weiteren Ausführung.

The invention is explained in more detail below with reference to an exemplary embodiment and the accompanying drawings. These show:

• 1 Schematic diagram of the equipment of a protective helmet, e.g. for firefighters,
• 2 Side view of a first PCM capsule for a protective helmet
• 3 Longitudinal section AA according to 2 ,
• 4 Detail B according to 3 ,
• 5 Representation of one of four individual first capsules 3.1, in two different views,
• 6 View of a helmet insert 2 from the direction of its open side with four first capsules 3.1,
• 7 Cut CC according to 6 ,
• 8 Illustration of a helmet spider 7 with four second capsules attached to it 4.1,
• 9 Illustration of a second capsule 4.1 from the direction of the inside of the helmet (front view),
• 10 Front view of a second capsule 4.1,
• 11 Exemplary schematic representation of a perforated pressurized gas line 4 for the supply of cooling gas,
• 12 Three-dimensional representation of a first version of a nozzle head for a protective helmet,
• 13 Longitudinal section through a nozzle head 4.2 acc. 12 ,
• 14 Section of a head spider 6 with a nozzle head 4.2 attached to it in a further version.

1 Figure 1 shows a schematic diagram of protective equipment in a protective helmet H, which, as is known, has a helmet shell 1 with a helmet insert 2 (as a shock absorber). In the helmet insert 2, facing towards the indicated head 8, there is a recess 2.1 in which at least one first capsule assembly 3 is located, filled with PCM material. At least one second capsule assembly 4, also containing PCM material, is positioned (here spaced apart from the first capsule 3) facing towards the head 8.

The second capsule arrangement 4 is surrounded by a perforated pressurized gas line 5.1 as a cooling device for supplying cooling gas into the interior. of the helmet H. A pressure gas line 5, indicated by dashed lines, leads from a pressure vessel (not shown) to the perforated pressure gas line 5.1.

The second capsule arrangement 4 and the perforated pressurized gas line 5.1 are preferably arranged or mounted on a so-called head spider 7 which is attached to fastening points 6.

The head spider 7 is a standard feature of a protective helmet H for special forces and sits on the head 8 when the protective helmet H is worn, enclosing and protecting it laterally and above.

The supply of cooling gas via line 5 and the perforated pressurized gas line 5.1 ensures a cool, dry microclimate inside the helmet through expansion cooling, as the cooling gas displaces the warm and humid air present inside the helmet and thus "flushes it out".

The first and second capsule arrangements 3, 4 serve as heat storage units, wherein the capsule arrangements 3, 4 are filled with phase change material PCM and the outer layer of the capsule arrangements 3, 4 forms a diffusion-tight protective shell.

The first capsule arrangement 3 can be made up of one or more parts, and the second capsule arrangement 4 can also consist of several parts.

The expansion cooling system consists of a pressure accumulator (not shown here) containing compressed gas, throttle/shut-off valves, a pressurized gas line 5 into the helmet interior, and the [unclear text]. 1 The perforated pressurized gas line 5.1 shown with outlet openings 5.2 for distributing the expanding gas inside the helmet.

Alternatively, the cooling gas can also be directed into the protective helmet H via one or more nozzle heads 12 or one or more air nozzles 13 connected to the pressurized gas line 5 (see also 12-14 ).

The first capsule arrangement 3, preferably integrated into the damping helmet insert 2 in the upper area of the protective helmet H, serves in particular to reduce the external heat input into the interior of the helmet.

The second capsule arrangement 4, located on the internal components (head spider 7), is situated directly on the head 7 and primarily serves to absorb the body heat emitted via the head 7.

Preferably, both the first and second capsule arrangements 3, 4 and the expansion cooling (perforated compressed gas line 5.1 with outlet openings 5.2 or one or more nozzle heads 12 or one or more air nozzles 13) are integrated into a helmet H, as this achieves the best results.

However, it is also possible to arrange the aforementioned components individually or in any combination within helmet H.

Furthermore, it is possible to integrate the compressed air supply into one or both capsules or capsule arrangements.

In 2 The side view of an example of a first capsule arrangement 3 for a protective helmet H is shown.

This is shaped like a shell and can be positioned in a corresponding recess/recess 2.1 of a helmet insert 2, as shown in 1 hinted at.

The longitudinal section of the 2 is in 3 This shows that the first capsule arrangement 3 consists of two shells 3a and 3b, between which the phase change material PCM is located.

Shells 3a and 3b, for example, consist of deep-drawn polycarbonate shells that are bonded together around their circumference and in which the phase change material PCM is enclosed.

4 shows the edge detail B according to 3 from which it can be seen that the two shells 3a, 3b are connected to each other in the edge region 3R of the first capsule arrangement 3. The connection is designed to be gas- and liquid-tight, so that no phase change material (PCM) can escape.

The first capsule arrangement 3 has at least one filling opening for filling the phase change material PCM and a venting opening (in the 2 to 4 (not shown).

It is advantageous to form the capsule arrangements 3, 4 from several parts, for example from four individual parts 3.1 in the first capsule arrangement 3, as in the 5 to 7 as indicated.

5 Figure 3 shows the representation of part 3.1 of four parts of a multi-part/four-part first capsule arrangement 3 in a front view (Figure a) and in a longitudinal section (Figure b).

It can be seen here that a filling opening 9 for the phase change material PCM and a venting opening 10 are provided. Part 3.1 of the first capsule arrangement 3 has an outer shell 3a and an inner shell 3b, which are connected to each other at their edges and between which there is a space for receiving the phase change material PCM (see figure b).

6 shows a view of the insert 2 of a protective helmet from the direction of its open side with a first capsule arrangement 3 of four parts 3.1 and 7 the AA cut according to 6 ,

The four parts 3.1 preferably border each other and are received in a recess 2.1 of the home insert 2.

From the 5 , representation b and 7 It can be seen that the parts 3.1 of the first capsule arrangement 3 have an outer shell 3a and an inner shell 3b, which are connected to each other at their edges. The phase change material PCM is located between these.

For example, parts 3.1 of the capsule assembly 3 can be manufactured from plastic using 3D printing.

8 Figure 4 shows a second capsule arrangement 4 consisting of four parts 4.1, each with a filling opening 9 and a venting opening 10 in each part 4.1, leading to a cavity formed in the part 4.1 for the phase change material.

Four parts 4.1 each are recorded on a metal band 7.1 of a head spider 7.

The individual presentation of part 4.1 is in 9 in the front view and in 10 shown in side view. Parts 4.1 have an unlabeled curvature adapted to a head shape. These are in the 9 and 10 The filling opening 9 and the venting opening 10 are also visible. Furthermore, each part 4.1 has at least one clamping element 11 for preferably detachable attachment to the metal band 7.1 of the head spider 7 (see also 8 ).

The capsule arrangements 3, 4, or their parts 3.1, 4.1, can consist of two shell-shaped individual shells connected at their edges, or, for example, can be manufactured as a single piece by blow molding or 3D printing. It is important that they have a cavity for the phase change material PCM.

Materials suitable for the capsule arrangements 3, 4 or their parts 3.1, 4.1 include in particular any printable, formable, blow-moldable plastics, preferably TPU (thermoplastic polyurethane), PC (polycarbonate), PA (polyamide), PP (polypropylene), PE (polyethylene), PVC (polyvinyl chloride).

However, other types of plastic capsules or capsules made of welded aluminum composite foil can also be used.

The exemplary schematic representation of a perforated pressurized gas line 5.1 for the supply of cooling gas is shown in 11 The outlet openings are not visible.

One pipe section runs around the head (not shown), and a second pipe section runs over the head. The pipe sections branch via connector 5.3. A pressurized gas line 5 also leads to a connector 5.3 from a pressurized gas reservoir, e.g., from a pressurized gas cylinder.

The arrows are intended to indicate how the cooling gas escapes from the perforated pressurized gas line 5.1 in the direction of the head not shown.

The perforated pressurized gas line 5.1 is preferably attached to the helmet spider.

Another option for supplying the cooling gas is the design of a nozzle head 12 (approximately shaped like a shower head) which has a connection 12.1 for a pressurized gas line 5 (indicated by dashed lines) and air guides 12.2. 12 shows a three-dimensional representation and 13 a longitudinal section of this nozzle head 12.

This is, for example, glued airtight into the helmet shell 2 and has a flattened section 12.3. Between the flattened section 12.3 and the inside of the helmet shell 2 (in 13 (Indicated by dashed lines) an air reservoir 12.5 is formed. A channel 12.4 leads from the connection 12.1 to the air reservoir 12.5 above the area 12.3. The cooling gas flows from the connection 12.1 through the channel 12.4 to the air reservoir 12.5 and from there via air ducts 12.2 towards the head.

Alternatively, this nozzle head 12 can also be attached to the helmet spider, in which case the channel 12.4 and the area above the flattened section 12.3 are closed at the top. Naturally, this expansion cooling option can also be combined with a first and/or second capsule arrangement containing PCM material.

14 shows a section of a head spider 7 with an attached air nozzle 13 for Supply of cooling gas into the helmet interior. The air nozzle 13 is preferably attached in the neck area and has a connection 13.1 for a pressurized gas line 5, which leads to a pressurized gas cylinder (not shown).

Any gas that is not toxic to the human body and does not accelerate fire can be used as a cooling gas, provided that the gases can be stored in pressure vessels.

The pressurized containers used as gas supplies should be designed so that they can be carried separately, e.g., on the back and/or helmet and/or otherwise. Alternatively, supply via a breathing apparatus may be possible.

The expansion cooling should be controlled and regulated according to demand, based on the parameters measured in the helmet.

Furthermore, it is advantageous to implement sound attenuation to reduce flow noise when the expanding gas enters the helmet interior (e.g., through silencers, outlet nozzles, suitable opening geometries on the pressurized gas line inside the helmet).

Phase change materials (PCMs) preferably consist of paraffins or salt hydrates, which, among other things, have melting temperatures between 25 and 80 °C, are compatible with health, and are non-flammable (up to at least 100 °C).

Furthermore, modified phase change materials (PCMs) can be used, for example, to improve thermal conductivity. This can be achieved, for instance, by adding highly thermally conductive additives to the phase change material.

An optimal mixture/composition can be determined, for example, through simulation calculations or experiments.

PCM is liquid when poured and then solidifies again at temperatures below its solidification temperature.

Advantageously, a system for measuring and evaluating vital parameters and condition variables should be provided inside the helmet. This system also advantageously measures the charge level of the PCM material and thus determines how much heat can still be stored.

This measurement is preferably performed using one or more temperature sensors in or on the first and/or second capsule assembly containing PCM material. Other measurement principles are also possible.

The vital parameters of the emergency personnel are recorded, for example, via pulse oximetry or infrared thermometry.

It is possible to send out visual, audible, and/or haptic warning signals to alert the helmet wearer, accompanying persons, and/or the incident command. The signals can be displayed on/in the helmet or on clothing or equipment. However, the signals can also be transmitted wirelessly (e.g., via radio) to an operations center, which can then respond accordingly.

• - mit Phasenwechselmaterial eine ca. 15°C geringere Temperatur
• - mit Expansionskühlung mit Kühlgas (hier Luft - zugeführt mit ca. 20 °C) eine bis zu 24 °C geringere Temperatur und
• - mit Phasenwechselmaterial und Expansionskühlung in Kombination eine bis zu 27 °C geringere Temperatur erzielt werden.

In laboratory-scale tests, 85°C was measured in the helmet space without the inventive equipment and when the inventive solution was used.

• - with phase change material, a temperature approximately 15°C lower
• - with expansion cooling using cooling gas (here air - supplied at approx. 20 °C) a temperature up to 24 °C lower and
• - a temperature reduction of up to 27 °C can be achieved by combining phase change material and expansion cooling.

In practical tests in a fire container, temperatures of 80-95 °C at 40-50 % relative humidity were measured using a firefighter's protective helmet without the equipment according to the invention.

With phase change material in a first and a second capsule arrangement 3, 4 and a perforated pressurized gas line 5, temperatures of 65 °C were still measured at only 10-15 % relative humidity.

The test subjects who wore the protective helmets in the fire container commented positively on the lower temperature and the improved climate inside the helmet due to the lower humidity.

By flushing the helmet with the cooling gas, cooled by expansion cooling, the high humidity otherwise generated by perspiration could be drastically reduced. The airflow of the cooling gas over the head thus has a very positive effect. The arrangement of the first and second capsules further reduces the temperature inside the helmet.

This can drastically reduce health problems for special forces during fire operations.

Reference symbol list

1

helmet shell

2

Helmet insert 2 (as a damper)

2.1

in-depth

3

first capsule arrangement

3.1

Parts of the first capsule assembly

3a

outer shell

3b

inner shell

3R

Edge area

4

second capsule arrangement

4.1

Parts of the second capsule arrangement

5

Compressed gas line

5.1

perforated pressurized gas line

5.2

Outlet openings

5.3

connector

5.4

Nozzle heads

5.5

Outlet nozzles

6

Mounting points

7

Head spider

8

Head

9

Filling opening

10

vent

11

Clamping element

12

Nozzle head

12.1

Connection

12.2

Air ducts

12.3

Area

12.4

channel

12.5

air reservoir

13

air nozzle

13.1

Connection

H

helmet

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions.

Cited patent literature

• EP 1 653 818 A4 [0003]
• DE 10 2010 020 262 B4 [0003]
• DE 10 2016 201 912 B4 [0004]
• WO 2016/135529 A1 [0005]
• DE 197 56 470 A1 [0006]
• EP 3 261 473 A4 [0007]
• EP 2 249 672 B1 [0009]
• WO 2011/098761 A1 [0011]

Claims (11)

Device for reducing thermal stresses and regulating the microclimate in a protective helmet (H), characterized in that at least one capsule arrangement (3, 4) with phase change material (PCM) is integrated into a helmet shell (1) of the protective helmet (H) and/or that a pressurized gas line (5) leads to the helmet shell (1), with which expansion cooling by means of a cooling gas inside the protective helmet (H) can be realized. Device according to Claim 1 , characterized in that at least one first capsule arrangement (3) is arranged in a helmet insert (2) of the protective helmet (H). Device according to Claim 1 , characterized in that at least a second capsule arrangement (4) is arranged on a head spider (7) of the protective helmet (H). Device according to Claim 1 until 3 , characterized in that - the first capsule arrangement (3) preferably integrated into the helmet insert (2) in the upper area of the protective helmet (H) causes a reduction of the external heat input into the interior of the helmet and/or - the second capsule arrangement (4) arranged on the inner fitting (head spider 7) is located directly in the area of the head (7) and causes the absorption of body heat emitted via the head (7). Device according to Claim 1 , characterized in that at least one perforated compressed gas line (5) and/or at least one nozzle head (12) and/or at least one air nozzle (13) are connected to the compressed gas line (5) in the helmet shell (1), through which the cooling gas is distributed in the helmet (H). Device according to Claim 5 , characterized in that the perforated pressurised gas line (5.1) and/or the nozzle head (12) and/or the air nozzle (13) are arranged on the head spider (7). Device according to Claim 6 , characterized in that the nozzle head is attached to the inside of the helmet shell (1) or to the head spider (7). Device according to one of the preceding claims, characterized in that the first and/or second capsule arrangement (3, 4) serve as heat storage devices. Device according to one of the preceding claims, characterized in that the first capsule arrangement (3) and/or the second capsule arrangement (4) are designed in one or more parts. Device according to one of the preceding claims, characterized in that the first capsule arrangement (3) consists of individual parts (3.1) and/or the second capsule arrangement (4) consists of individual parts (4.1) and that the first and second capsule arrangement (3, 4) or their individual parts (3.1, 4.1) each have a filling opening (9) for the phase change material (PCM) and a venting opening (10). Protective helmet having a device according to one of the Claims 1 until 10 .