Airbag fabric

Abstract

An airbag fabric (20) for an airbag has a main woven portion (28), which forms at least 50% of the airbag fabric (20), and at least one special woven portion (31, 32), which is integrally connected to the main woven portion (28). The main woven portion (28) and the special woven portion (31, 32) have different bindings. The special woven portion (31, 32) here is a loading portion which is arranged outside a tab-shaped fastening region (22) for fastening the airbag.

Description

[0001] Gasbag fabric

[0002] The invention relates to a gas bag fabric for a gas bag.

[0003] Gasbag fabrics for gasbags are well known.

[0004] Furthermore, it is known to design such airbag fabrics with fastening areas by means of which a corresponding airbag is attached, for example, to a steering wheel or to a roof frame in the case of a head-side airbag, and is held in place during inflation. When the airbag is deployed in this way, the fastening areas are subjected to significant stress in a defined direction and must therefore be designed to be particularly tear-resistant. To ensure particularly high tear resistance in this area, these fastening areas are often reinforced with additional fabric layers or metal fittings.

[0005] Even outside these attachment areas, there are airbag sections that must meet particularly stringent requirements, especially those with high loads. Current technology typically involves additional layers of fabric sewn on to reinforce these areas, which, however, increases the volume and manufacturing complexity of the airbag.

[0006] The object of the invention is to provide a gas bag fabric for a gas bag which meets particularly high requirements and is of simple design.

[0007] The object is achieved by a gas bag fabric for a gas bag, comprising a base woven section that forms at least 50% of the gas bag fabric, and at least one special woven section that is integrally connected to the base woven section. The base woven section and the special woven section have different weaves. Furthermore, the special woven section is a load-bearing section that is arranged outside a tab-shaped fastening area for fastening the gas bag.

[0008] The invention has recognized that by deliberately selecting a weave that differs from the basic weave from which the majority of the airbag fabric is made, specific areas of the airbag can be specially designed. Using these special weave sections, the airbag fabric can thus be designed with minimal effort so that the airbag made from this airbag fabric meets even the most stringent requirements.

[0009] In particular, within the meaning of the invention, a load section is a section which, in the case of restraint, ie when a vehicle occupant is triggered and subsequently restrained during an accident, is exposed to a load which is at least 150%, optionally at least 200% of the lowest load in the basic weave section, in particular which is at least 150%, optionally at least 200% of the average load in the basic weave section in the case of restraint.

[0010] In one embodiment, the special woven section has a coating and / or a lamination. The weave of the special woven section can be designed to ensure better adhesion of coatings and laminations compared to the base woven section, for example, by the special woven section having a surface with a higher roughness than the base woven section due to its weave.

[0011] In a further embodiment, the weave of the special weave section has a first knot density and the basic weave section has a weave with a second knot density. The first knot density is lower than the second knot density. The knot density defines the number of knots per area of ​​the fabric. For the purposes of the application, knots are points where warp threads and weft threads cross. In particular, a point where two or more parallel warp and / or weft threads cross, as is the case with a Panama weave, for example, is regarded as a single knot, regardless of the number of threads that cross at that point. Due to the reduced number of knots, the weave of the load-bearing section has a lower displacement resistance than the weave of the transition section.In the prior art, load-bearing sections are formed with weaves that exhibit particularly high displacement resistance and thus retain their structure even under high loads. It has been recognized that by a defined reduction in the displacement resistance in the special woven section, a fastening area can be created with increased breaking strength. This is the result of a fiber bead that forms when the fabric threads shift relative to one another. Thus, at this point, a load does not act on each fiber individually, which would potentially cause them to tear one after the other, but rather the load acts on all fibers of the fiber bead together, so that it can absorb a greater load before it tears or breaks.In other words, by shifting the fabric threads to form a fiber bead, a larger number of fabric threads counteract the load at the same time and thus represent a greater resistance that must be overcome to break through the fabric than would be the case if the fabric had the same weave as the basic weave section.

[0012] It can be provided that the weave of the basic weave section is a (1 / 1) plain weave, in which one warp thread and one weft thread cross in a knot and which is therefore also referred to as a (1 / 1) weave.

[0013] Additionally or alternatively, the weave of the special woven section can be a Panama weave, especially a (2 / 2) Panama weave. Due to their systematic nature, Panama weaves have a particularly low knot density and differ significantly in their properties from a simple (1 / 1) plain weave, particularly in terms of tensile strength and surface roughness.

[0014] According to one embodiment, the special woven section is multi-layered, particularly two- or three-layered. The threads of the layers merge seamlessly into the weave of adjacent sections of the airbag fabric. The multi-layered design of the special woven section allows a fiber bulge to form in each layer, allowing the special woven section to absorb greater loads. According to another embodiment, the special woven section is arranged adjacent to or borders an inflation opening of the airbag. In this way, the area surrounding the inflation opening, which is subject to significant stress in the event of restraint, can be designed to be particularly resilient.

[0015] Additionally or alternatively, the special woven section can be arranged adjacent to or adjacent to a fastening area for fastening the gas bag in order to reinforce this area, which is exposed to particularly high loads in the case of restraint.

[0016] Furthermore, the special woven section can be part of a gas bag chamber section that forms a wall of an inflatable chamber. In this case, the wall is also partially formed by the base woven section. As an integral part of the gas bag chamber section, the special woven section directly enhances its properties.

[0017] In one embodiment, the airbag fabric is a one-piece woven (OPW) fabric, in which the threads of opposite walls of an inflatable chamber merge into a common weave at the edges. This means that the entire airbag fabric is formed in one piece, thus making it particularly simple to design.

[0018] In a further embodiment, the fabric of the special weave section has a tear propagation resistance which is at least 150%, in particular at least 200%, of the tear propagation resistance of the fabric of the basic weave section, so that an effective fiber bead is reliably formed under load, which counteracts further tearing of the gas bag fabric.

[0019] In particular, the special weaving section has an area of ​​at least 200 mm 2 . As a result, the special weave section has a size by means of which the weave of the special weave section has a particularly significant effect on the properties of the gas bag fabric.

[0020] Further advantages and features will become apparent from the following description and the accompanying drawings, in which: - Figure 1 shows a schematic sectional view of part of a gas bag with a gas bag fabric according to the invention, and

[0021] - Figure 2 shows a schematic sectional view of a section of the

[0022] Gas bag fabric from Figure 1.

[0023] The following detailed description, taken in conjunction with the accompanying drawings, in which like numerals refer to like elements, is intended to describe various embodiments of the disclosed subject matter and is not intended to be the only embodiments. Each embodiment described in this disclosure is merely exemplary or illustrative and should not be construed as preferred or advantageous over other embodiments.

[0024] All features disclosed below with respect to the embodiments and / or the accompanying figures may be combined alone or in any sub-combination with features of the aspects of the present disclosure, including features of preferred embodiments, provided that the resulting combination of features is meaningful to a person skilled in the art.

[0025] Figure 1 shows a gas bag 10 which is formed from a gas bag fabric 20.

[0026] The gas bag 10 has an inflatable chamber 12 which is delimited by opposing walls 14, 16, and an edge 18 with several fastening areas 22 (see Figure 2).

[0027] In principle, the gas bag 10 can have any number of fastening areas 22.

[0028] In the illustrated embodiment, the airbag 10 is a one-piece woven (OPW) airbag. This means that the airbag fabric 20 is a piece of OPW fabric manufactured using a weaving process, also referred to as the OPW process.

[0029] The two walls 14, 16 form two parallel woven layers, the threads of which are combined in the edge 18 to form a common weave, i.e., they run into each other. The edge 18 thus comprises twice the number of threads, while the walls 14, 16 each have a single number of threads. The tab-shaped fastening areas 22 have a fastening opening 24 and are provided for fastening the gas bag 10 by means of fastening means (not shown) that extend through the fastening openings 24 in the assembled state.

[0030] In principle, the tab-shaped fastening areas 22 can be designed in any desired manner.

[0031] The gas bag 10 also has an inflation mouth 26 (see Figure 2), through which it is inflated in the restraint case, for example by means of a gas generator.

[0032] In this case, the gas bag 10 is held back in a loading direction B (see Figure 1) by the fastening means in the fastening openings 24.

[0033] As shown in Figure 2, the major part of the gas bag fabric 20 is formed by a basic weave section 28.

[0034] The proportion of the basic weave section 28 in the entire gas bag 10 is at least 50%.

[0035] The basic weave section 28 is in particular part of a gas bag chamber section 30, which delimits the chamber 12 and forms the walls 14, 16.

[0036] Furthermore, the gas bag fabric 20 has a first special weaving section 31 and a second special weaving section 32, which are each integrally connected to the basic weaving section 28.

[0037] The first special weaving section 31 is arranged here adjacent to the injection mouth 26.

[0038] In an alternative embodiment, the first special weaving section 31 can be directly adjacent to the injection mouth 26.

[0039] The second special weaving section 32 is arranged here adjacent to one of the fastening areas 22.

[0040] In an alternative embodiment, the second special woven section 32 can be arranged directly adjacent to one of the fastening regions 22. In the present embodiment, the special woven sections 31, 32 are part of the gas bag chamber section 30, but this may also be different.

[0041] In principle, any number of special weaving sections 31, 32 can be provided, each of which is arranged at any location outside the tab-shaped fastening areas 22.

[0042] In the illustrated embodiment, the special weaving sections 31, 32 each have an area of ​​1200 mm 2 on.

[0043] The second special weaving section 32 has the shape of a rectangle with edge lengths of 20 mm and 60 mm.

[0044] Of course, in an alternative embodiment, the special weaving sections 31, 32 can each have any shape with any area, in particular with an area of ​​at least 200 mm 2 .

[0045] In all cases, the one or more special weave sections 31, 32 are load sections of the gas bag 10.

[0046] In this context, the first special weaving section 31 is laminated.

[0047] Additionally or alternatively, the first special weaving section 31 may have a coating.

[0048] In general, the special weaving sections 31, 32 can each have a lamination and / or a coating or can be designed without lamination and without coating.

[0049] The weave of the basic weave section 28 is a (1 / 1) plain weave, which has a high resistance to displacement.

[0050] The special weaving sections 31, 32 each have a weave which has a lower resistance to displacement compared to the weave of the basic weaving section 28.

[0051] In the present exemplary embodiment, the special weave sections 31, 32 are each formed by two superimposed fabric layers with a (2 / 2) Panama weave, i.e., a weave in which two warp threads and two weft threads intersect in a knot, thus forming a checkerboard pattern whose fields each have a width of two warp threads and two weft threads, respectively. Each of these fields forms a knot.

[0052] The threads of the superimposed fabric layers of the special weave sections 31, 32 merge integrally into the single-layer woven base weave section 28 and each have half the thread count of the base weave section 28 in the corresponding area. As a result, the gas bag fabric 20 is formed as an OPW fabric piece and thus has a particularly simple design.

[0053] Due to this design with two layers and a (2 / 2) Panama weave, the knot density of the weave of each fabric layer of the special weaving sections 31, 32 is 1 / 8 of the knot density of the plain weave of the basic weaving section 28, which is formed in one layer.

[0054] In principle, the special weaving sections 31, 32 can each have any weave as long as they have a different weave than the basic weaving section 28.

[0055] Furthermore, the special weaving sections 31, 32 can each have any number of fabric layers, in particular a single fabric layer or three or more fabric layers.

[0056] In embodiments with a special woven section 31, 32 with a single fabric layer, the threads of the special woven section 31, 32 preferably merge integrally into the single-layer woven base woven section 28, as in a special woven section 31, 32 with multiple superimposed fabric layers. Thus, the special woven section 31, 32 and the base woven section 28 are each formed as a single layer and each have the same number of threads. The special woven section 31, 32 differs from the base woven section 28 in the type of its weave, which in particular has a lower displacement resistance and / or a lower knot density than the weave of the base woven section 28. In this way, the gas bag fabric 20 can be formed as an OPW fabric piece and can be designed in a particularly simple manner.

[0057] Preferably, the knot density of the weave of the special weave section 31, 32 or of each fabric layer of the special weave section 31, 32 is at most half, in particular at most 1 / 3 of the knot density of the weave of the basic weave section 28.

[0058] Furthermore, it is advantageous if the special weave section 31, 32 has a tear resistance that is at least half greater than the tear resistance of the base weave section 28. Preferably, the tear resistance of the load section is at least twice as great as the tear resistance of the base weave section 28.

[0059] This provides a gas bag fabric 20 that can absorb large loads and is easy to manufacture. Because the special weave sections 31, 32 have a different weave than the basic weave section 28, these areas are specifically designed to withstand even high loads.

[0060] Furthermore, the weave of the special weave sections 31, 32 has the advantage that, due to the higher surface roughness compared to the weave of the basic weave section 28, coatings and laminations form a more stable connection with the gas bag fabric 20, whereby these sections are particularly resistant.

Claims

Patent claims 1. A gas bag fabric (20) for a gas bag (10), comprising a basic weave section (28) which forms at least 50% of the gas bag fabric (20), and at least one special weave section (31, 32) which is integrally connected to the basic weave section (28), wherein the basic weave section (28) and the special weave section (31, 32) have different weaves, and the special weave section (31, 32) is a load-bearing section which is arranged outside a tab-shaped fastening region (22) for fastening the gas bag (10).

2. Gas bag fabric (20) according to claim 1, characterized in that the special woven section (31, 32) has a coating and / or a lamination.

3. Gas bag fabric (20) according to claim 1 or 2, characterized in that the weave of the special weave section (31, 32) has a first knot density and the basic weave section (28) has a weave with a second knot density, wherein the first knot density is lower than the second knot density.

4. Gas bag fabric (20) according to one of the preceding claims, characterized in that the weave of the base weave section (28) is a (1 / 1) plain weave.

5. Gas bag fabric (20) according to one of the preceding claims, characterized in that the weave of the special weave section (31, 32) is a Panama weave, in particular a (2 / 2) Panama weave.

6. Gas bag fabric (20) according to one of the preceding claims, characterized in that the special woven section (31, 32) is multi-layered, in particular two-layered or three-layered.

7. Gas bag fabric (20) according to one of the preceding claims, characterized in that the special weave section (31, 32) is arranged adjacent to or adjacent to an inflation mouth (26) of the gas bag (10).

8. Gas bag fabric (20) according to one of the preceding claims, characterized in that the special weave section (31, 32) is adjacent to a fastening area (22) for fastening the gas bag (10) or is adjacent to it.

9. Gas bag fabric (20) according to one of the preceding claims, characterized in that the special weave section (31, 32) is part of a gas bag chamber section (30) which forms a wall (14, 16) of an inflatable chamber (12), the wall (14, 16) also being formed in sections by the basic weave section (28).

10. Gas bag fabric (20) according to one of the preceding claims, characterized in that the gas bag fabric (20) is a one-piece woven fabric in which the threads of opposite walls (14, 16) of an inflatable chamber (12) merge into a common weave at the edges.

11. Gas bag fabric (20) according to one of the preceding claims, characterized in that the fabric of the special weave section (31, 32) has a tear propagation resistance which is at least 150%, in particular at least 200%, of the tear propagation resistance of the fabric of the basic weave section (28).

12. Gas bag fabric (20) according to one of the preceding claims, characterized in that the special weave section (31, 32) has an area of ​​at least 200 mm 2 has.

Images