Avalanche airbag

Description

[0001] This invention relates to an avalanche airbag for an avalanche airbag system. Furthermore, the invention relates to a method for manufacturing an avalanche airbag and an avalanche airbag system comprising such an avalanche airbag.

[0002] Avalanche airbag systems protect people in the event of being buried by an avalanche. A key component of these systems is an airbag, which inflates rapidly when needed to provide additional buoyancy. The inflated airbag increases the volume of the person caught in the avalanche, who might be wearing a backpack with the deployed avalanche airbag system. This reduces the likelihood of the person being buried by the snow. Therefore, one of the requirements for the airbag in an avalanche airbag system is that it remains sufficiently gas-tight for a certain period of time and under increased pressure, and does not collapse immediately after inflation.

[0003] Furthermore, the avalanche airbag must be designed to withstand high mechanical stresses that can act on it from the outside. During an avalanche, the airbag can come into contact with rocks, trees, and the like, resulting in very high local stresses on the airbag in a short period of time. If the airbag can withstand an internal pressure of 0.3 bar for at least three minutes and the airbag material also meets the prescribed requirements for, for example, tensile strength and tear resistance, then it can be assumed that the airbag will withstand avalanche situations well.

[0004] Avalanche airbags must inflate as quickly as possible after deployment and maintain a volume of at least 150 liters for at least 3 minutes. After deployment, the airbag must contain a volume of at least 150 liters within a maximum of 5 seconds at a slight overpressure. This is typically achieved through the use of sufficiently gas-tight coated airbag materials.

[0005] The packed volume of well-known avalanche airbags is relatively large because it's difficult to pack the airbag very tightly. This becomes particularly challenging at low temperatures, as the airbag materials used become significantly stiffer and less flexible at low temperatures. This means that more energy is required to deploy the avalanche airbag.

[0006] It is very important that the avalanche airbag can be packed in the backpack with as little volume as possible. Following a specific folding pattern in the instructions is often the way to achieve a small pack size. However, even with optimal folding, the pack size is still relatively large. Ideally, the user wouldn't have to fold the avalanche airbag at all, but could simply stuff it back into the backpack.

[0007] EP 0 957 994 B1 discloses an avalanche rescue system with an avalanche airbag comprising a buoyancy body with a two-chamber design, wherein the outer shell is made of uncoated polyamide fabric and the inner balloon of PU-coated polyamide fabric. Allegedly, such an avalanche airbag can be folded or "crumpled" into a significantly smaller size, thereby also reducing its packed dimensions.

[0008] The object of the present invention is to further develop and improve such an avalanche airbag with a two-chamber design, as well as to create a method for manufacturing such an avalanche airbag and an avalanche airbag system comprising such an avalanche airbag.

[0009] This problem is solved by an avalanche airbag, a method for manufacturing such an avalanche airbag, and an avalanche airbag system comprising such an avalanche airbag with the features of the independent claims. Advantageous embodiments and further developments of the invention are specified in the dependent claims and in the following description.

[0010] The avalanche airbag according to the invention comprises an deployable first bag or outer bag, wherein a deployable second bag or inner bag of the avalanche airbag is arranged inside the outer bag. The outer bag can be referred to as the "outer airbag" or "first bag," and the inner bag can be referred to as the "inner airbag" or "second bag." In particular, the terms "first bag" and "outer bag" are used synonymously in the following, as are the terms "second bag" and "inner bag." The outer bag and the inner bag are two separate bags, with only the inner bag being gas-tight. The outer bag and the inner bag are partially connected to each other.

[0011] The outer bag is made of a flexible, gas-permeable material. This flexibility and gas permeability make folding and packing easier, and also allow for a low weight and small pack volume without air pockets.

[0012] In contrast, the inner bag consists of a gas-tight and stretchable material, and is inflatable with gas. Due to the gas-tightness of the inner bag material, little to no gas can escape from the inflated airbag or avalanche airbag through the inner bag material during and after deployment. Furthermore, the inner bag material is stretchable, with an elongation of between 25% and 500%, preferably at least 50%, and particularly preferably about 300%. Elongation refers to the property of a material to change its shape under the influence of force. It indicates how far a material can be stretched without breaking or tearing. When external forces act on the outer bag, these forces can be transferred to the inner bag.In the event of an avalanche, branches or rocks can impact the outer bag, and the forces are transferred from the outer bag to the inner bag. Due to the elasticity of the inner bag's material, the inner bag absorbs the deformations transmitted from the outer bag very well without tearing. The elasticity of the inner bag material, preferably up to 300%, prevents the inner bag from tearing in such extreme situations.

[0013] In the avalanche airbag according to the invention, it is advantageous that the outer bag is connected to the inner bag at several points. This prevents a large crease from forming on the inner bag during packing, which could increase the time required to deploy the avalanche airbag.

[0014] The first bag, made of flexible, gas-permeable material, is preferably only expandable, but not or hardly expandable. In contrast, the gas-tight material of the second bag or inner bag has an extensibility of at least 25%. Consequently, the extensibility of the gas-tight material of which the second bag or inner bag is made is at least 25%, preferably at least 50%, particularly preferably about 300%, greater than the non-existent (or virtually non-existent) extensibility of the flexible, gas-permeable material of which the expandable first bag is made. Thus, even if there is some slight extensibility of the flexible, gas-permeable material of the expandable first bag or outer bag, the extensibility of the gas-tight material of which the second bag is made is considerably greater, namely at least 25% greater.

[0015] If, for example, a branch or similar object impacts the inflated avalanche airbag from the outside, an indentation or similar feature can form in the flexible, gas-permeable material of the outer bag. This inelastic deformation of the outer bag's material can cause an elastic deformation of the stretchable material of the inner bag. The relatively high elasticity of the inner bag's material prevents it from tearing. This is advantageous because it largely prevents air and / or gas from escaping the inflated avalanche airbag, thus ensuring the airbag retains its protective function.

[0016] In particular, because the outer and inner bags are only connected at certain points and not across their entire surface, the formation of indentations or depressions in the outer bag material can lead to stress on the inner bag material, causing it to stretch. Therefore, the inner bag's greater elasticity (at least 25% greater than that of the outer bag) is especially advantageous when the outer bag is subjected to external stresses that could cause it to move relative to the outer bag.

[0017] Furthermore, the elasticity of the gas-tight material of the inner bag makes the avalanche airbag particularly easy to pack when stowed in a backpack of the avalanche airbag system. This is especially true because the second bag, or inner bag, made of gas-tight and elastic material, is only partially connected to the outer bag. This allows for relative movement between the flexible, non-elastic outer bag and the stretchable or elastically stretchable inner bag when packing the avalanche airbag.

[0018] The avalanche airbag allows for rapid deployment after activation across a wide temperature range, as well as a small packing volume and low overall weight of the avalanche airbag.

[0019] The outer bag, when inflated, preferably has a predetermined contour, and the inner bag, due to its elasticity, can adapt to this contour during inflation. After the airbag is deployed, the internal pressure within the inner bag presses the airtight inner bag tightly against the supporting outer bag. The inflation of the inner bag and the resulting elastic stretching of the inner bag thus cause it to conform to the inner surface of the outer bag. Advantageously, the predetermined contour of the outer bag limits further expansion of the inner bag's material. This is because the flexible, gas-permeable material from which the first bag or outer bag is made is at least largely inelastic or virtually non-extensible.

[0020] The greater elasticity of the inner bag, or first bag, compared to the essentially non-elastic outer bag, allows the inner bag to be smaller, and in particular significantly smaller, when the avalanche airbag is deflated. This is because the inner bag, due to its elasticity, can be adapted to the contours of the outer bag during inflation. Such a design is advantageous for particularly easy packing or storage of the avalanche airbag, for example, by folding and / or crumpling it.

[0021] Furthermore, the contour and / or shape of the unfolded outer bag (which has not yet been inflated to its predetermined shape or contour) and the shape and / or contour of the uninflated inner bag (made of the stretchable material) may differ. Accordingly, these shapes and / or contours do not need to be similar. Due to the elasticity of the inner bag's material, the inner bag can adapt to the predetermined contour of the outer bag during inflation and thus fill the outer bag, even if its uninflated contour and / or shape differs from that of the uninflated outer bag. This allows for a great deal of flexibility in the design of each bag. This is also advantageous for easily packing or storing the uninflated or unfilled avalanche airbag.

[0022] While the outer bag or first bag can maintain its predetermined shape or contour in the inflated state of the avalanche airbag simply by unfolding and preferably without stretching the material of the first bag, the inner bag or second bag may be designed to adapt to the contour of the first bag due to its elasticity.

[0023] The inner bag itself also has a predetermined contour, whereby the contours of the outer and inner bags can be designed such that, when the outer and inner bags are laid flat on top of each other, they are almost congruent and thus similar. The contour of the inner bag can therefore be the same size as, or slightly smaller than, the contour of the outer bag. If the contour of the inner bag, when laid flat or uninflated, deviates only slightly from the contour of the flat outer bag, the elasticity of the material of the second bag allows it to be easily adapted to the predetermined contour of the first bag by inflation. This prevents any undesirable stretching of the inner bag during inflation.This means that the material of the inflated inner bag retains a relatively large degree of elasticity, should a branch, tree, rock, or similar object impact the outer bag of the inflated avalanche airbag from the outside. This is advantageous.

[0024] During inflation of the inner bag, the outer bag unfolds along with it. Inflation of the inner bag ends when the outer bag is fully inflated. Although the outer and inner bags are two independent bags at this point, their contours essentially conform to each other.

[0025] Therefore, it is not necessary for the outer bag material to be gas-tight, as the gas that inflates the inner bag cannot escape due to the gas-tightness of the inner bag's material. This allows significantly more freedom in the choice of material for the outer bag; for example, knitted fabrics or meshes with an opening width of up to 10 mm are conceivable.

[0026] According to one embodiment, the outer bag and the inner bag each have a gas inlet opening, with the outer bag's edge areas being connected to each other and enclosing the inlet opening, and the inner bag's edge areas being connected to each other and enclosing the inlet opening. Edge areas refer to the areas along the edges of the material blanks from which the respective bag is manufactured.

[0027] The two inlet openings preferably have a similar appearance, with the inlet opening of the outer bag being slightly larger than the inlet opening of the inner bag. Preferably, the two inlet openings are gas-tightly connected to each other by a retaining ring, which fixes the two inlet openings to a gas supply hose or similar air inlet duct in such a way that gas cannot escape from the inner bag. The two inlet openings may also not be rigidly connected to each other in the area of ​​the inlet openings, particularly as long as it is ensured that the inner bag is supported by the outer bag.

[0028] Preferably, the outer and inner bags are connected to each other at several points, either at specific points or across multiple surfaces. This allows for excellent mobility of the inner bag relative to the outer bag. This is advantageous for quick and easy packing and unpacking of the avalanche airbag when moving it into a stowable position. Furthermore, it allows for optimal utilization of the inflated inner bag's elasticity when the outer bag is subjected to external forces, such as a branch, rock, or similar object.

[0029] The outer bag and the inner bag can be connected to each other, particularly outside the edge areas, for example, at specific points. This means that a side of the outer bag facing the inner bag and a side of the inner bag facing the outer bag are connected to each other at at least one point, which is preferably not located at the edge areas. Preferably, this point connection is made by gluing or welding.

[0030] The outer bag and the inner bag can also be joined together over a surface area, particularly outside the edge regions. This means that a side of the outer bag facing the inner bag and a side of the inner bag facing the outer bag are joined together at least on one surface, which preferably does not include the edge regions, whereby the outer bag and the inner bag are not joined over their entire surface. Preferably, the joining at the respective surface areas is achieved by gluing or welding.

[0031] Spacing the points where the outer bag and the inner bag are connected from the edge areas of the outer bag and the inner bag is particularly advantageous with regard to easy folding and / or collapsing and / or crumpling when stowing the avalanche airbag, i.e. when putting the avalanche airbag into its stowable position.

[0032] Preferably, the outer bag is made of a textile material. This textile material is soft, adaptable, and flexible, produced by creating a network of yarns or threads. This textile material is particularly well-suited to giving the inner bag or outer bag the desired flexibility while simultaneously providing high resistance to mechanical stress.

[0033] It is therefore important that the outer bag has sufficient tensile strength and tear resistance. These values ​​are preferably determined using a standardized tensile test. The tensile strength of the outer bag material is preferably at least 1500 N / 5 cm according to EN-ISO 13934-1 in both warp and weft, and the tear resistance is preferably at least 70 N according to EN-ISO 13937-2 in both warp and weft. Such strengths are particularly suitable for preventing damage to the outer bag, for example, due to external forces from branches and / or rocks. At the same time, these strengths ensure that the unfolded outer bag, once inflated and shaped into its predetermined form and / or contour by means of the inner bag, is highly dimensionally stable.

[0034] The outer bag material can be woven, knitted, or crocheted from a polymer, particularly a polyamide, polyolefin, or polyester, such as polyamide 6.6, UHMWPE (e.g., from Dyneema), or aromatic polyamide (e.g., Kevlar). Due to the strong bond between the yarns and / or threads, such textiles are particularly well-suited to giving the outer bag the desired flexibility and foldability, as well as the desired tensile strength and tear resistance.

[0035] Polyamide 6.6 is a semi-crystalline polyamide characterized by high heat resistance and low water absorption. The textile known as PA 6.6 Nylon Cordura Ripstop 210D, for example, has proven particularly suitable because its ripstop effect provides high tear resistance at a low basis weight. Ultra-high molecular weight polyethylene (UHMWPE) is chemically similar to the familiar thermoplastic polyethylene but has very long molecular chains with a molecular mass of more than 3.5 million g / mol. Furthermore, the outer bag material can also consist of hybrids of the aforementioned materials. The outer bag can also be made of a high-strength polyester film, such as the one sold under the trade name "Mylar."

[0036] Preferably, the yarns and / or threads of the outer bag material have a thread count between 50 dtex and 150 dtex, preferably around 110 dtex. Thread count of yarns is a measure of their thickness, diameter, or strength. The smaller the diameter of such a structure, the finer it is. Such comparatively fine threads or yarns facilitate folding the outer bag when stowing the avalanche airbag and unfolding the outer bag when inflating the avalanche airbag. Furthermore, the use of such fine threads or yarns allows the weight per unit area of ​​the outer bag to be kept comparatively low.

[0037] The basis weight of the outer bag should be between 80 g / m² and 130 g / m², and the combined basis weight of the outer and inner bags should not exceed 140 g / m². Ideally, the total basis weight of both bags should be less than 100 g / m². Manufacturers of the outer bag material include, for example, Hoyu (Taiwan), TomLong (Taiwan), Hwa-sung (Korea), and IBQ (Barcelona, ​​Spain).

[0038] Preferably, the material of the inner bag consists of thermoplastic polyurethane (TPU) or silicone elastomer, or the material of the first bag comprises a thermoplastic polyurethane (TPU) and / or a silicone elastomer. Such polymers make it particularly easy to achieve the desired gas tightness and simultaneously high elasticity of the material of the second bag or inner bag.

[0039] Thermoplastic polyurethane belongs to a class of polyurethane plastics with many properties advantageous for this application, particularly high elasticity and durability. Technically, these are thermoplastic elastomers consisting of linear, segmented block copolymers composed of hard and soft segments. Silicone elastomer most often refers to a silicone-based polymer that has been vulcanized. The inner bag material can also consist of hybrids of the aforementioned materials.

[0040] Preferably, the inner bag material has a thickness of 20 µm to 50 µm. This is advantageous with regard to good elasticity of the inner bag material and its low weight. Furthermore, it is preferred if the inner bag material has a weight of 20 g / m² to 50 g / m². This allows the weight of the avalanche airbag to be kept low. An ether-based TPU, such as Platilon 4201 AU from Covestro, has proven to be a preferred material for the inner bag.

[0041] According to one design variant, the outer bag is formed from at least two layers, which lie on top of each other in the finished outer bag and are connected to each other along their edges. The finished inner bag is also formed from at least two layers, which are gas-tightly connected to each other along their edges, with the at least two layers of the inner bag positioned between the at least two layers of the outer bag. This ensures that, firstly, no air or gas can escape from the inner bag when the avalanche airbag is inflated or is already inflated. At the same time, the inner bag is very well protected by the outer bag, which encloses it. This is advantageous for the high functionality of the avalanche airbag.

[0042] The two layers in the finished bag can each consist of either two separate pieces of material or a single piece of material folded accordingly. A cavity is created between the two layers of the outer bag, containing the inner bag. This inner bag is filled with gas to inflate the avalanche airbag. Preferably, the at least two layers of the outer bag are joined by sewing, gluing, and / or welding. Preferably, the at least two layers of the inner bag are also joined gas-tight by gluing and / or welding.

[0043] When the inflated airbag is used, particularly high stresses occur at the joints and seams. However, when sewing seams to the outer, preferably textile, layer, gas tightness is not a concern, as the inner layer already provides gas tightness. This means that when creating stable seams, there is no need to seal them afterwards.

[0044] The welds and / or adhesive joints created during the gas-tight joining of the at least two layers of the inner bag are preferably positioned such that a material protrusion remains outside the welds and / or adhesive joints, which can be used to connect the outer bag to the inner bag. Providing such a material protrusion and using it to connect the outer bag to the inner bag in the area of ​​the protrusion advantageously ensures good adhesion between the two bags of the avalanche airbag.

[0045] Preferably, the seams created when joining the layers of the outer bag are single or double T-seams or overlap seams. Such seams are characterized by particularly high strength, especially against tensile loads. This is advantageous with regard to the resistance of the first bag to loads acting on it from the outside and / or from within.

[0046] Preferably, an anti-blocking agent is added to the material of the at least two layers of the inner bag to prevent them from sticking or sticking together. If the avalanche airbag is not deployed for a very long time, the layers of the inner bag, which are made of TPU, for example, remain pressed tightly together. If the inner bag is made of TPU film, for example, there is a risk of the layers sticking or sticking together. This can be prevented by treating the layers of the inner bag with the anti-blocking agent.

[0047] The inclusion of an anti-blocking agent therefore supports the proper functioning of the avalanche airbag, particularly with regard to easy and effortless inflation. Specifically, the finished inner bag can be coated with a small amount of talc to reliably prevent it from sticking or clogging.

[0048] It is advantageous if the inner bag has a reinforcing layer between at least two layers of the second bag in the area of ​​the edges where the layers of the inner bag are gas-tightly connected, because a weld seam along the edges reduces the material strength. By providing the reinforcing layer, the material strength in the area of ​​the gas-tight connection between the edges can be increased. This results in increased robustness of the inner bag in the area of ​​the gas-tight connection between the layers of the inner bag.

[0049] This reinforcing layer is preferably placed between the layers of the inner bag to be joined before the gas-tight sealing process. The portion of the reinforcing layer outside the seam or weld is then removed. The reinforcing layer thus essentially exists as a flat band that serves to reinforce the connection regions of the inner bag. Preferably, the reinforcing layer is joined to the two layers of the second bag by gluing and / or welding. The reinforcing layer serves to increase the strength of the connection between the at least two layers of the inner bag.

[0050] A particularly preferred material for the reinforcement layer is an identical, the same, or similar material to that used for the inner bag (e.g., TPU or silicone elastomer). This facilitates the integration of the reinforcement layer when bonding the layers of the second bag's material and results in particularly easy processing of the reinforcement layer together with the layers of the second bag.

[0051] Preferably, the thickness of the reinforcing layer is 25 µm to 50 µm. This makes the reinforcing layer easy to work with, especially when creating a weld seam to create a gas-tight connection between the layers of material in the second bag. Nevertheless, the increase in weight of the inner bag or second bag caused by the reinforcing layer is negligible.

[0052] The finished avalanche airbag is preferably combined with an airbag inflation system and installed in or attached to a backpack. The avalanche airbag system according to the invention therefore comprises a backpack, an avalanche airbag according to the invention or an avalanche airbag manufactured according to the invention arranged in or attached to the backpack, and an airbag inflation system connected to the avalanche airbag.

[0053] The airbag inflation system serves to force air and / or another gas into the avalanche airbag in such a way that the airbag is inflated as quickly as possible. The air used for inflation can be drawn from the environment, and the avalanche airbag can be inflated by means of a blower or similar device, wherein the blower or device is preferably powered or supplied with electrical energy by at least one electrical energy storage device, in particular by a supercapacitor or a plurality of supercapacitors. The gas used for inflation can also come from a pressurized container, e.g., a gas cartridge, and be forced into the avalanche airbag due to the overpressure in the cartridge.Preferably, when using the cartridge for the airbag inflation system, the avalanche airbag is filled with both the gas from the cartridge and ambient air, which is drawn in from the surroundings as the gas escapes from the cartridge. The cartridge is usually stored in the same backpack as the avalanche airbag.

[0054] The avalanche airbag according to the invention has the following technical advantages and effects.

[0055] Because the outer bag, responsible for the mechanical strength of the avalanche airbag, is made of a gas-permeable material, this material can be very flexible, soft, and lightweight. This makes the outer bag very light and allows for a very compact pack size. This material can also be selectively reinforced anisotropically to strengthen areas subject to high stress. A very thin, lightweight, and gas-tight material is used for the inner bag. As a result, the avalanche airbag is lighter overall, has a very small pack volume, and deploys very quickly at low temperatures.

[0056] The inner bag is highly gas-tight, so it's unnecessary to add more air or gas after the avalanche airbag has been deployed. This means that the energy required to inflate the avalanche airbag is lower, especially with electrically powered systems. This is important because the capacity of the airbag inflation system's battery or electrical energy storage unit is limited, and this unit should be lightweight. Furthermore, the lower energy requirement for airbag deployment allows for a smaller power supply, resulting in a reduced weight and volume for the entire avalanche airbag system.

[0057] A method according to the invention for manufacturing an avalanche airbag comprising an inner bag and an outer bag comprises at least the following steps.

[0058] At least two layers of a first material and at least two layers of a second material are cut to size as needed. The two layers of the first material can consist of two corresponding pieces or of one piece folded along a predetermined line and placed on top of each other, so that the two layers are already joined on one side. This also applies to the two layers of the second material. The cut layers of the first material are of any shape and as identical to each other as possible. The shape of the cut layers of the first material is preferably similar to or identical to the shape of the cut layers of the second material. This simplifies the production of the avalanche airbag.

[0059] However, it is also possible that the shape of the cut layers of the second material intended to form the inner bag or second bag may differ from the shape of the cut layers of the first material intended to form the first bag or outer bag. This is because, due to the elasticity of the second material, the shape of the inner bag can adapt to the shape of the outer bag as it unfolds during inflation of the avalanche airbag.

[0060] The at least two layers of the second material are then placed on top of each other and gas-tightly joined to form the inner bag. Preferably, the gas-tight joining is achieved by welding or bonding. The gas-tight joining is preferably carried out along the edge regions of the at least two layers of the inner bag.

[0061] To position the inner bag inside the outer bag, the outer bag can be constructed around the finished inner bag. For this, the at least two layers of the first material are laid on top of each other so that the inner bag is located between the layers of the first material. The inner bag is preferably placed between the layers of the first material in such a way that it is completely enclosed on all sides by the layers of the first material. The layers of the first material are then joined together to form the outer bag. In this way, the avalanche airbag can be manufactured very simply from the respective layers of the first material, which form the first bag, and the layers of the second material, which form the second bag. Nevertheless, it is advantageous that the first bag or outer bag and the second bag or inner bag are designed as two separate, self-contained bags.This is because when providing the outer bag, gas tightness does not need to be taken into account, and when providing the inner bag, lower requirements must be met regarding the resistance of the inner bag material to external stresses than when providing the outer bag.

[0062] In the inventive method for manufacturing the avalanche airbag, a flexible, gas-permeable material is used as the first material from which the deployable first bag is formed, and a gas-tight, stretchable material is used as the second material from which the deployable and gas-inflatable second bag is formed, with the second bag being arranged inside the first bag. Furthermore, the material of the second bag has an elongation of at least 25%. The advantages described in this regard for the avalanche airbag also apply to the method for manufacturing the avalanche airbag. In the inventive method for manufacturing the avalanche airbag, the first bag is connected to the second bag at several points.

[0063] Preferably, the layers of the first material are joined by sewing, welding, or gluing. The joining preferably takes place along the edges of the at least two layers of the first material, so that the inner bag is completely enclosed by the at least two layers of the first material. This ensures that the second bag or inner bag is very well protected by the stable and durable outer bag.

[0064] Furthermore, the avalanche airbag can also be manufactured as follows. The at least two layers of the first material and the at least two layers of the second material are cut to size as needed. The layers of the first material are placed on top of each other and joined together to form the outer bag. Preferably, the joining is done by sewing, welding, or gluing. The joining preferably takes place along the edges of the at least two layers of the first material, but remains interrupted in one area to create an opening in the outer bag through which the outer bag and the inner bag can be pulled through (and turned inside out) as they go.A special opening or entry point for turning the airbag can be omitted if an existing airbag air inlet is dimensioned such that the airbag or avalanche airbag can be turned through it. The at least two layers of the second material are then placed on top of each other, so that the outer bag is sandwiched between the layers. The layers of the second material are then gas-tightly bonded together to form the inner bag. This gas-tight bonding is preferably achieved by welding or gluing. The gas-tight bonding is again preferably carried out along the edges of the two layers of the inner bag and is interrupted to create an opening in the inner bag through which the outer and inner bags can be turned, so that the inner sides are then on the outside.To turn the bag inside out, the outer bag is pulled out of the inner bag through the opening of the inner bag, while simultaneously turning it inside out through the opening of the outer bag. Then, the inner bag is pushed into the outer bag through the opening of the outer bag, while simultaneously turning it inside out through the opening of the inner bag.

[0065] Alternatively, the outer and inner bags can be pulled through their respective entry openings simultaneously and turned inside out together. According to a preferred method, these entry openings can then be used to inflate the inner bag with air and / or gas via the airbag inflation system. The advantage of turning the bag inside out is that the seams of the finished avalanche airbag are on the inside. Consequently, the seams are well protected, and damage to them is largely avoided.

[0066] Cutting the layers of the first and second materials can be done, for example, using a laser cutter. A laser cutter can cut a wide variety of materials, such as TPU, to an accuracy of 0.1 mm based on a digital template. As with a cutting plotter, a prerequisite is preferably the creation of a two-dimensional graphic or drawing, for example, on a computer. This can be implemented using a vector graphics program, such as Inkscape.

[0067] Furthermore, at least one reinforcement element can be provided on the outer bag for securing the avalanche airbag to the backpack and / or its carrying system. Preferably, the reinforcement element is a tear-resistant textile used to attach the avalanche airbag to the backpack or its carrying system. The pull-out strength of the reinforcement element between the avalanche airbag and the backpack is preferably at least 3,000 N. It is advantageous that the reinforcement element on the outer bag can be designed without regard to the airbag's gas tightness, as the outer bag does not need to be gas-tight. This allows for a high degree of freedom in the design of the attachment of such reinforcement elements between the backpack and the avalanche airbag.

[0068] The avalanche airbag system preferably comprises the backpack, the avalanche airbag located in or attached to the backpack, the airbag inflation system connected to the avalanche airbag, and a triggering system. The airbag inflation system serves to fill the avalanche airbag with air and / or another gas. As mentioned, the air or gas can originate from the environment and / or from a cartridge and is preferably forced into the interior of the inner bag through the two inlet openings of the outer and inner bags. The backpack essentially serves to securely stow the avalanche airbag and the airbag inflation system and to keep the avalanche airbag in place on the user after deployment.

[0069] The advantages and preferred embodiments described for the avalanche airbag according to the invention apply analogously to the method according to the invention as well as to the avalanche airbag system according to the invention and vice versa.

[0070] The features and combinations of features mentioned above in the description, as well as those subsequently mentioned in the figure description and / or shown in the figures alone, are not only usable in the combinations specified, but also in other combinations or on their own, without departing from the scope of the invention. Thus, embodiments that are not explicitly shown or explained in the figures, but which can be derived and generated from the explained embodiments by separate combinations of features, are also to be considered as encompassed and disclosed by the invention. Thus, embodiments and combinations of features that do not exhibit all the features of an originally formulated independent claim are also to be considered disclosed.Furthermore, embodiments and combinations of features, in particular those set out above, are to be considered disclosed which go beyond or deviate from the combinations of features set out in the cross-references of the claims.

[0071] Further advantages, features, and details will become apparent from the following description of preferred embodiments and from the drawings. These show: Fig. 1 shows an avalanche airbag system in a perspective view; Fig. 2 shows a reinforcement element of the avalanche airbag in a top view; Fig. 3 schematically represents the avalanche airbag according to a first variant; Fig. 4 schematically represents the avalanche airbag according to a second variant; Fig. 5 schematically represents the avalanche airbag according to a third variant; and Fig. 6 schematically represents the avalanche airbag according to a fourth variant.

[0072] In the figures, identical or functionally equivalent elements are provided with identical reference symbols.

[0073] Fig. 1 Figure 1 schematically shows an avalanche airbag system 1, comprising an avalanche airbag 2, a backpack 3, and an airbag inflation system with an inflation device 4 for filling the avalanche airbag 2. The avalanche airbag 2 in Fig. 1 is completely inflated by air and / or gas, which has been driven into the avalanche airbag 2 through an air inlet channel 5 of the airbag filling system.

[0074] The inflation device 4 is stored in the backpack 3. Preferably, the inflation device 4 comprises a blower, an electric motor for driving the blower, and at least one supercapacitor or similar electrical energy storage device as an energy source for supplying the motor, wherein the blower drives air from the environment through the air inlet channel 5 into the inner bag of the avalanche airbag 2. Alternatively, the inflation device 4 can also comprise a cartridge filled with gas.

[0075] A release handle 8, attached to a carrying system 7 of the backpack 3, is connected to the inflation device 4 via a pull cord 9 or the like. Pulling the release handle 8 activates the inflation device 4, thus inflating the airbag or avalanche airbag 2. Automatic triggering by appropriate algorithms or remote triggering is also preferably possible. The air inlet duct 5 is connected at one end to the inflation device 4 and at the other end to inlet openings 6 of the avalanche airbag 2, the air inlet duct 5 being gas-tightly connected to the inlet openings 6 by a connecting element 10. This gas-tight connection is preferably achieved by gluing, crimping, or welding.

[0076] First, the avalanche airbag 2 is folded up and stowed in the backpack 3. To avoid possible burial by snow, the user pulls the trigger handle 8, so that the air and / or gas from the inflation device 4 flows through the air inlet channel 5 into the avalanche airbag 2.

[0077] Fig. 2 Figure 1 shows the avalanche airbag 2 with a reinforcement element 11 in a top view. The reinforcement element 11 serves to reliably connect the avalanche airbag 2 to the backpack 3. When the avalanche airbag 2 is inflated, it is tear-resistant and connected to the backpack 3 via the reinforcement element 11, thus ensuring that the user wearing the backpack 3 retains the additional buoyancy provided by the avalanche airbag 2 in an avalanche.

[0078] Fig. 3 Figure 1 schematically shows a longitudinal section of the avalanche airbag 2 according to a first example. The avalanche airbag 2 comprises an outer bag 12 and an inner bag 13. The outer bag 12 and the inner bag 13 can each be referred to as the "first bag" and "second bag" or "outer airbag" and "inner airbag". The inner bag 13 is arranged inside the outer bag 12. The inner bag 13 is made of a gas-tight and stretchable material, and the outer bag 12 is made of a flexible and air-permeable material.

[0079] The outer bag 12 consists of two layers 19, 20. The inner bag 13 consists of two layers 21, 22. The two layers 19, 20 of the material of the outer bag 12 can consist of two material cuts, whereby the two layers 19, 20 are completely separate, or of one cut which is folded along a predetermined line and placed on top of each other, so that the two layers 19, 20 of the material of the outer bag 12 are formed.

[0080] This also applies to the two layers 21, 22 of the material of the inner bag 13. The inner bag 13 is connected to the outer bag 12 at certain points, e.g., at specific spots or over a larger area. Preferably, this connection is made by gluing. The points 16 are therefore either specific spots or larger areas. The two layers 21, 22 of the inner bag 13 are welded together along their edges, forming weld seams 15.

[0081] A reinforcing layer 23 lies between the two layers 21, 22 of the inner bag 13 and completely covers the weld seams 15 to reinforce them, the reinforcing layer 23 preferably being a maximum of 100 mm wide. Outside the weld seams 15, there is preferably a material overhang 17 of the two layers 21, 22 of the inner bag 13. The material overhang 17 is located in the variant according to Fig. 1 between the two layers 19, 20 of the outer bag 12 and is sewn to layers 19, 20 of the outer bag 12 in the form of T-seams 14, i.e. seams having a T-shape in cross-section.

[0082] The inlet openings 6 comprise an inlet opening of the inner bag 13 and an inlet opening of the outer bag 12. The respective inlet openings 6 are preferably connected to each other by welding, clamping, or gluing such that the inlet opening of the outer bag 12 surrounds the inlet opening of the inner bag 13, with the inlet opening of the inner bag 13 forming a gas-tight seal around the air inlet channel 5. The air inlet channel 5 is connected to these inlet openings 6, preferably in a gas-tight seal.

[0083] Fig. 4 The diagram schematically shows the avalanche airbag 2 according to a second example. The second example according to Fig. 4 differs from the first example according to Fig. 3 because a possible material protrusion 17 is not connected to the outer bag 12. In this case, the weld seams 15 are located away from the T-seams 14 of the layers 19, 20 of the outer bag 12.

[0084] Fig. 5 The diagram schematically shows the avalanche airbag 2 according to a third example. The third example according to Fig. 5 differs from the first example according to Fig. 3 by the fact that the material protrusion 17 lies between the two layers 19, 20 of the outer bag 12 and is sewn to them in such a way that overlap seams 18 are created or formed.

[0085] Fig. 6 The diagram schematically shows the avalanche airbag 2 according to a fourth example. The fourth example according to Fig. 6 differs from the third example according to Fig. 5by the fact that a possible material protrusion 17 of the inner bag 13 is located away from the overlap seams 18 of the layers 19, 20 of the outer bag 12. In this case, the weld seams 15 of the inner bag 13 are located away from the overlap seams 18 of the layers 19, 20 of the outer bag 12.

Claims

1. An avalanche airbag (2) comprising a deployable first bag (12), which is composed of a flexible, gas-permeable material, and a deployable second bag (13), which is composed of a gastight, stretchable material and is inflatable with gas, wherein the second bag (13) is arranged within the first bag (12), wherein the material of the second bag (13) has a stretchability of at least 25 %, and wherein the first bag (12) is connected to the second bag (13) at multiple locations (16).

2. The avalanche airbag (2) according to claim 1, characterized in that the first bag (12) has a preset contour in an inflated state, wherein the second bag (13) adapts to the contour of the first bag (12) upon inflating due to its stretchability.

3. The avalanche airbag (2) according to claim 1 or 2, characterized in that the first bag (12) and the second bag (13) are connected to each other point by point at the multiple locations (16) and / or in extensive manner at the multiple locations (16).

4. The avalanche airbag (2) according to any one of the preceding claims, characterized in that the material of the first bag (12) is a textile material.

5. The avalanche airbag (2) according to claim 4, characterized in that the material of the first bag (12) has a tensile strength, which is more than 1500 N / 5 cm in warp direction and in weft direction, and a tear propagation resistance, which is more than 70 N in warp direction and in weft direction.

6. The avalanche airbag (2) according to claim 4 or 5, characterized in that the material of the first bag (12) is a tissue, knitted fabric or interlaced fabric, in particular a tissue, knitted fabric or interlaced fabric of polyamide 6.6, UHMWPE or Kevlar.

7. The avalanche airbag (2) according to any one of the preceding claims 4 to 6, characterized in that yarns and / or threads of the material of the first bag (12) have a thread fineness between 50 dtex and 150 dtex.

8. The avalanche airbag (2) according to any one of the preceding claims, characterized in that the material of the second bag (13), in particular having a thickness of 20 µm to 50 µm, includes thermoplastic polyurethane (TPU) and / or silicone elastomer.

9. The avalanche airbag (2) according to any one of the preceding claims, characterized in that the first bag (12) is formed of at least two superimposed plies (19, 20), which are connected to each other along their edge areas, and the second bag (13) is formed of at least two superimposed plies (21, 22), which are connected to each other in gastight manner along their edge areas, wherein the at least two plies (21, 22) of the second bag (13) are arranged between the at least two plies (19, 20) of the first bag (12).

10. The avalanche airbag (2) according to claim 9, characterized in that an anti-blocking agent for preventing sticking or adhering together of the at least two plies (21, 22) of the second bag (13) is added to the material of the at least two plies (21, 22) of the second bag (13).

11. The avalanche airbag (2) according to claim 9 or 10, characterized in that the second bag (13) comprises a reinforcing layer (23) between the at least two plies (21, 22) of the second bag (13) in the edge areas, along which the at least two plies (21, 22) of the second bag (13) are connected to each other in gastight manner.

12. The avalanche airbag (2) according to claim 11, characterized in that the reinforcing layer (23) in particular having a thickness of 25 µm to 50 µm is composed of the same material as the plies (21, 22) of the second bag (13).

13. A method for producing an avalanche airbag (2), which comprises a first (12) and a second bag (13), comprising the following steps: - cutting at least two plies (19, 20) of a first material and at least two plies (21, 22) of a second material to size; - superimposing the at least two plies (21, 22) of the second material and connecting them in gastight manner to form the second bag (13); - superimposing the at least two plies (19, 20) of the first material such that the second bag (13) is situated between the at least two plies (19, 20) of the first material; and - connecting the at least two plies (19, 20) of the first material to form the first bag (12), wherein a flexible, gas-permeable material is used as the first material, of which the deployable first bag (12) is formed, wherein a gastight, stretchable material is used as the second material, of which the deployable second bag (13) inflatable with gas is formed, wherein the second bag (13) is arranged within the first bag (12), wherein the material of the second bag (13) has a stretchability of at least 25 %, and wherein the first bag (12) is connected to the second bag (13) at multiple locations (16).

14. The method according to claim 13, characterized in that upon gastight connection of the at least two plies (21, 22) of the second bag (13), seams (15) arise, which are placed such that a material overhang (17) remains outside of the seams (15), which is used to connect the first bag (12) to the second bag (13).

15. An avalanche airbag system (1) comprising: a backpack (3); an avalanche airbag (2) according to any one of claims 1 to 12 or produced according to claim 13 or 14, arranged in the backpack (3) or at the backpack (3); and an airbag filling system connected to the avalanche airbag (2).