DE102021113620A1 - Airbag with an adaptive ventilation device - Google Patents

Abstract

An airbag with a ventilation device is described. This airbag has an outer skin with a first opening, an additional layer with a second opening which at least partially overlaps the first opening, and a bib which is at least partially located between the outer skin and the additional layer. Furthermore, a holding element is provided with a first end area which is attached at least in sections to the bib, a second end area and a middle area which connects the first end area and the second end area. In order to improve the properties of the ventilation device, at least part of the central area of the holding element is guided in a tunnel which extends along a section of the outer skin (Fig. 5).

Description

The invention relates to an airbag with an adaptive ventilation device according to the preamble of claim 1 and an airbag module with such an airbag according to claim 14.

Airbags with an adaptive vent are well known in the automotive art. Such an adaptive ventilation device usually consists of a hole in the outer skin of the airbag and a bib. This bib (and thus the ventilation device) has at least a first state and a second state such that the coverage of the hole in the second state differs from the coverage in the first state. It is also known to control this bib with the help of a holding element.

From the generic WO 2020 011 634 A1 it is known to place the bib between a portion of the skin of the airbag and an additional layer, both the skin of the airbag and the additional layer having an opening. When the airbag is inflated and the tether is in tension, the bib at least partially covers at least one of the openings such that the vent means is in a closed or restricted first condition, and when the airbag is inflated and the tether is not in tension, the bib covers this opening less than in the first state, so that the ventilation device is in a second state. The bib is generally in the shape of a triangle and the tether extends from an apex of this triangle. The retention member has a first end portion attached to the bib, a second end portion, and a middle portion connecting the first end portion and the second end portion. This type of adaptive venting device and in particular the triangular shape of the bib has been found to work very well.

Proceeding from this state of the art, it is the object of the invention to further improve a generic venting device.

This problem is solved by an airbag with the features of claim 1. An airbag module having such an airbag is defined in claim 14.

According to the invention, at least part of the central area of the holding element is guided in a tunnel which extends along a section of the outer skin. This tunnel clearly defines the position of the retaining element in all states of the airbag, ie in the folded state, during deployment and in the inflated state. This has several advantages: First of all, the defined position of the holding element can lead to improved gas tightness in the first state of the adaptive venting device. In addition, the retaining element is reliably prevented from being caught on another element of the airbag module when the airbag is deployed.

In one embodiment, the tunnel is formed by the portion of the skin along which the tunnel extends and a tunnel member that is attached to the skin of the airbag by first and second attachment joints such that a minimum of additional material is required.

In another embodiment, the tunnel is formed by a tubular tunnel element that is attached to the outer skin. In this embodiment, the tunnel can be displaced by a small amount relative to the outer skin. For some geometries this can be an advantage.

In the embodiment just mentioned, the tunnel element is usually connected by a locking connection, e.g. B. a closure seam closed. This locking connection can also connect the hose to the outer skin so that only one connection needs to be made. Alternatively, the hose can also be connected to the outer skin via a further connection that is not the sealing connection. In some cases, this can facilitate production, since the assembly of the holding element and the hose can be prefabricated.

In order to reduce friction within the tunnel, it is preferred that at least the central portion of the retaining element consists of at least one strand with a substantially circular or oval cross-section so that it has a small surface area.

In order to ensure a uniform transmission of force between the holding element and the bib - particularly in the aforementioned case of a substantially circular or oval cross-section - it is also preferred that the first end region comprises a first end section and a second end section, both end sections being connected to the bib are connected, and wherein the end portions preferably define a first angle greater than 0°, more preferably greater than 30° and even more preferably between 45° and 90°. In this case, the central region preferably consists of two parallel sections, each of these sections being in one piece with an end section. Even more preferably, the holding element comprises a common strand, the Endab the end portions of the common strand are cut so that the second end portion is looped and easily attachable to a fastener.

A particularly preferred application of the invention is an airbag module with a fastening means to which the second end area is detachably fastened, so that the venting device can be actively controlled.

• 1 alle für die Erfindung relevanten Teile einer ersten Ausführungsform eines Airbags sowie ein Verbindungselement, das für ein Airbagmodul mit dem erfindungsgemäßen Airbag verwendet wird,
• 2 den Latz und ein Halteelement, das aus dem in gezeigten Strang gebildet ist, nach einem ersten Montageschritt,
• 3 die zusätzliche Lage und den Zuschnitt für das Tunnelelement wie in 1 gezeigt, nach einem weiteren Montageschritt,
• 4 die in 2 dargestellte Unterbaugruppe nach einem weiteren Montageschritt, nämlich nach dem Annähen des Latzes an die Außenhaut des Airbags,
• 5 das in 4 Gezeigte, nachdem die Unterbaugruppe aus 3 an die Außenhaut genäht wurde,
• 6: einen Schnitt entlang der Ebene A-A in 5,
• 6a: eine Variante zu dem in 6 Gezeigten,
• 6b: eine weitere Variante zu dem in 6 Gezeigten,
• 6c: eine Variante zu dem in 6b Gezeigten,
• 7: eine schematische Darstellung des vollständigen Airbagmoduls in einem Zustand, in dem der Airbag vollständig aufgeblasen ist und sich seine Entlüftungseinrichtung in ihrem geschlossenen ersten Zustand befindet,
• 8: das in Dargestellte, nachdem die Entlüftungseinrichtung durch Lösen des zweiten Endbereichs des Halteelements vom fixierten Teil des Verbindungselements in ihren offenen zweiten Zustand übergegangen ist,
• 9: einen Zuschnitt für einen Latz einer zweiten Ausführungsform,
• 10 den aus dem Zuschnitt aus 9 gefalteten Latz und das daran befestigte Halteelement,
• 11 eine Alternative zu dem in 9 gezeigten Zuschnitt,
• 12 eine zweite Ausführungsform der zusätzlichen Lage,
• 13: eine dritte Ausführungsform der zusätzlichen Lage, und
• 14: eine vierte Ausführungsform der zusätzlichen Lage.

The invention will now be described using preferred embodiments with a view to the figures. The figures show:

• 1 all parts relevant to the invention of a first embodiment of an airbag and a connecting element that is used for an airbag module with the airbag according to the invention,
• 2 the bib and a retaining element consisting of the in strand shown is formed after a first assembly step,
• 3 the additional layer and the cut for the tunnel element as in 1 shown after a further assembly step,
• 4 in the 2 Subassembly shown after a further assembly step, namely after sewing the bib to the outer skin of the airbag,
• 5 this in 4 Shown after the subassembly is made 3 sewn to the outer skin
• 6 : a section along the plane AA in 5 ,
• 6a : a variant of the in 6 shown,
• 6b : another variant to the in 6 shown,
• 6c : a variant of the in 6b shown,
• 7 : a schematic representation of the complete airbag module in a state in which the airbag is fully inflated and its venting device is in its closed first state,
• 8th : this in Illustrated after the ventilation device has changed over to its open second state by releasing the second end region of the holding element from the fixed part of the connecting element,
• 9 : a blank for a bib of a second embodiment,
• 10 the one from the cutting 9 folded bib and the attachment element attached thereto,
• 11 an alternative to the in 9 shown cut,
• 12 a second embodiment of the additional layer,
• 13 : a third embodiment of the additional layer, and
• 14 : a fourth embodiment of the additional layer.

shows - highly schematically - all relevant elements of a first embodiment of the airbag according to the invention and a connecting element that can be used in an airbag module with this airbag.

The airbag naturally has an outer skin 10 from which 1 only an excerpt is shown. A first opening 12 is provided in this outer skin 10 . This first opening 12 has a circular shape, which is often preferred but not mandatory. An additional layer 14 is also provided; the blank for this additional layer 14 is also in shown. The blank for this additional sheet 14 has a second opening 16 which may be the same size and shape as the first opening 12 . The additional sheet 14 has a substantially triangular portion in which the second opening 16 is provided and a connecting portion extending from this substantially triangular portion. A blank for a bib 20 is also provided. In the first embodiment, this bib and its blank are identical and consist solely of a substantially triangular body 21, so for the first embodiment the terms "blank for bib""bib" and "body of bib" can be used interchangeably. The triangular shape of the bib 20 is similar to the triangular portion of the additional layer 14 but smaller than it. Since the blank/bib 20 is essentially triangular, it naturally has a first edge 21a and a second edge 21b which enclose a first angle α between 30° and 70°. Because the bib 20 is generally triangular, the first edge 21a and the second edge 21b are connected by a third edge 21c. A blank for a tunnel member 25 has the same width as the connecting portion of the additional layer 14. It would also be possible to provide a single blank for the additional layer and tunnel, but for practical reasons it is often preferred to provide two blanks as shown. The skin 10 and the panels 14, 20 and 25 may all be made from the same material, particularly a woven plastics material typically used in the manufacture of Air bag cushion is used. Finally, a strand 30' is provided for a holding element. In the first embodiment, this cord 30' is in the form of a rope with a substantially circular cross-section. Of course, this strand 30' extends from a first end to a second end.

Although not part of the airbag as such, it is in 1 a connecting element 50 shown schematically. This connector 50 may be part of an airbag module comprising the airbag of the items described above for releasably attaching a second end of a tether made from the strand 30' to a housing. This connecting element 50 can, for example, from that in FIG DE 10 2011 014 869 B4 be of the type described. This connecting element 50 consists of a fixed part 52 and a breakable part 54 (including a pyrotechnic igniter), as in the just mentioned DE 10 2011 014 869 B4 is described in detail.

To form the holding element 30, the first end section 32 of the strand 30' is sewn to the bib 20 along the first edge 21a of the bib 20 by means of a seam 42 and the second end section 33 of the strand along the second edge 21b of the bib 20 by means of a seam 43 to the bib 20 , so that the first end section 32 and the second end section 33 also have the first angle α ( 2 ) lock in. This fastening process creates a first end region 31 of the holding element 30. This first end region 31 is Y-shaped and includes a connecting region 31a consisting of the two end sections 32 and 33 which, as already mentioned, are sewn to the bib 20. This shape of the first end area 31 and in particular of its connecting area 31a leads to an even distribution of force when the holding element is under tension and thus to a flat and well-closing bib. In addition, breakage of a seam, the holding element or the bib is prevented.

A central region 34 of the holding element 30 extends from this first end region 31, in which two sections of the strand 30' run parallel to one another. The second end region 36 of the holding element, which adjoins the middle region 34, is loop-shaped and is formed by the middle section of the strand. In the embodiment shown, tether connections 38 are provided between the first end region 31 and the central region 34 and between the central region 34 and the second end region 36 .

As in As can be seen, the tunnel element 25 is sewn to the additional layer 14 by means of a seam 44 .

In the next step, the bib 20 is sewn to the outer skin 10 by means of a seam 45 that extends along the third edge 21c of the bib 20 ( ).

Finally, the sub-assembly consisting of the additional layer 14 and the tunnel element 25 is sewn to the outer skin 10. In this embodiment, this is accomplished by a single seam 46. This subassembly covers the bib 20 and at least a portion of the central region 34 of the tether 30. The result is shown in FIGS 5 and 6 shown.

Although it is preferred to use a rope of substantially circular cross-section as the strand for the support member (see Fig 6 ), it would also be possible to use a band-shaped element to form the holding element ( 6a) , so that a double-layered main section is formed. In this case, the two layers could be joined together by a seam.

How from the 6 and 6a As can easily be seen, the tunnel, in which at least part of the central region 34 of the retaining element is guided, can be formed between the tunnel element 25 and the outer skin 10 of the airbag, which are connected to one another by a first section 46a and a second section 46b of the seam 46 are connected. These two sections form a first and a second fastening connection. In a further embodiment, which is 6b As shown, the tunnel could be formed solely by tunnel member 25 defining a tube. In this case the tunnel element forms a closed loop, which is closed by a seam 47 forming a locking connection. The hose can be connected to the outer skin 10 by an additional seam 46 which forms a further connection. In a further alternative embodiment, in which a tube also forms the tunnel, the seam 47 forming the sealing connection also connects the tube to the outer skin ( 6c ).

shows the airbag 5 just described as part of an airbag module. The airbag module also includes a housing 60, an inflator 62 and the connecting element 50, with which the loop-shaped second end region 36 of the holding element 30 is connected to the housing 60. This connecting element serves as a fastener. In the embodiment shown, the additional layer 14 is arranged on the inside of the skin 10, but it would also be possible to arrange the additional layer 14 on the outside of the skin 10. As is known from the prior art, the bib 20 is located between the Outer skin 10 and the additional layer 14 and blocks the flow of gas through the first opening 12 and the second opening 16 as long as it is held in position by the holding element 30. The retaining element 30 is largely guided in the tunnel, which runs through the tunnel element 25 and a section of the outer skin 10 (or in the variant of the 6b is formed by the tunnel element alone), so that the position of the holding element is clearly defined. The loop-shaped end portion 36 of the holding element is held by the breakable part 54 of the connecting element 50, as is the case, for example, in FIG DE 10 2011 014 869 B4 is known. In this condition, the tether 30 is under tension when the skin of the airbag is fully deployed.

If the loop-shaped second end region 36 is now released, the holding element loses its tension and the bib 20 is pushed out of the first opening 12 and gas can flow out of the interior of the airbag 5, as is known from the prior art.

• Die 9 und 10 zeigen eine zweite Ausführungsform eines Latzes 20. Im Gegensatz zur ersten Ausführungsform sind dieser Latz 20 und sein Zuschnitt 20' nicht identisch, denn ein Teil des Latzes ist mehrlagig, nämlich dreilagig. Der Zuschnitt 20' des Latzes 20 hat also vier Abschnitte, nämlich einen Abschnitt 20a' für den Hauptteil 21 und drei Abschnitte 20b' bis 20d' für einen vorstehenden Teil. In einem ersten Schritt werden die Abschnitte 20c' und 20d' auf einen mittleren Abschnitt 20b' des vorstehenden Teils gefaltet, so dass der Latz 20 die in 10 gezeigte Form erhält, in der sie einen im Wesentlichen dreieckigen Hauptteil 21 und einen ebenfalls im Wesentlichen dreieckigen vorstehenden Teil 22 aufweist. Dieser vorstehende Teil 22 ist - wie bereits erwähnt - mehrlagig. Der Hauptteil 21 hat die gleiche Funktion wie der Latz 20 der ersten Ausführungsform, nämlich die Abdeckung der Öffnungen 12, 16 in der Außenhaut 10 und in der zusätzlichen Lage 14. Seine Form ist also im Wesentlichen die gleiche wie bei der ersten Ausführungsform, und der erste Endabschnitt 32 des Halteelements 30 ist entlang der ersten Kante 21a und der zweite Endabschnitt 33 des Halteelements 30 entlang der zweiten Kante 21b vernäht. Der vorstehende Teil 22 dient auch zum Vernähen des Halteelements mit dem Latz 20. Das Halteelement 30 umfasst also einen ersten zusätzlichen Verbindungsabschnitt 32a, der sich von dem ersten Endabschnitt 32 erstreckt, und einen zweiten zusätzlichen Verbindungsabschnitt 33a, der sich von dem zweiten Endabschnitt 33 erstreckt. Diese zusätzlichen Verbindungsabschnitte 32a, 33a erstrecken sich entlang der vierten und fünften Kante 22a, 22b des vorstehenden Teils 22 und schließen somit einen zweiten Winkel β ein, der kleiner ist als der erste Winkel α. Durch diese Geometrie und die Tatsache, dass der vorstehende Teil mehrlagig ist, kann die mangelnde Elastizität des seilartigen Strangs kompensiert und ein Bruch eines der beteiligten Elemente verhindert werden.

As already mentioned, a cable-like strand is often preferred for the tether, mainly because it causes much less friction in the tunnel. A disadvantage of such a rope-like strand is that it is generally less extensible than a ribbon-like strand. When the airbag deploys, the stress peaks are therefore higher than in the case of a ribbon-shaped strand. Depending on the overall geometry, additional measures must be taken to reliably avoid breakage. The second embodiment of the bib now described is particularly suitable for an airbag in which a belt element made of a rope-like strand with low elasticity is used:

• the 9 and 10 show a second embodiment of a bib 20. In contrast to the first embodiment, this bib 20 and its blank 20' are not identical because part of the bib is multi-layered, namely three-layered. The blank 20' of the bib 20 thus has four sections, namely a section 20a' for the main part 21 and three sections 20b' to 20d' for a protruding part. In a first step, the portions 20c' and 20d' are folded onto a central portion 20b' of the protrusion so that the bib 20 has the in 10 shown shape, in which it has a substantially triangular main part 21 and a also substantially triangular protruding part 22. This protruding part 22 is - as already mentioned - multi-layered. The main part 21 has the same function as the bib 20 of the first embodiment, namely to cover the openings 12, 16 in the outer skin 10 and in the additional layer 14. Its shape is therefore essentially the same as in the first embodiment, and the the first end portion 32 of the holding element 30 is sewn along the first edge 21a and the second end portion 33 of the holding element 30 is sewn along the second edge 21b. The protruding part 22 also serves to sew the holding element to the bib 20. The holding element 30 thus comprises a first additional connection section 32a which extends from the first end section 32 and a second additional connection section 33a which extends from the second end section 33 . These additional connecting sections 32a, 33a extend along the fourth and fifth edges 22a, 22b of the protruding part 22 and thus enclose a second angle β which is smaller than the first angle α. Due to this geometry and the fact that the protruding part is multi-layered, the lack of elasticity of the rope-like strand can be compensated and a breakage of one of the elements involved can be prevented.

shows a variant of the in shown blank 20 '. The bib resulting from this cut 20' is only double-layered in the protruding part, ie the cut 20' has only two sections 20b', 20c' for this protruding part.

In some cases it may not be necessary to provide a multi-layer protruding portion: the shape of the bib 20 alone, providing an elongate portion for attachment of the tether, may be useful.

In addition, the protruding part, in particular a double-layered one, as in shown, replace a separate retaining element. In this case, the protruding part forms the holding element.

As in shown, it may be preferable to subdivide the hole 16 by means of a ridge 18 extending substantially perpendicularly to the direction of the retaining element, in order to limit deformations. If the additional layer 16 is on the inside of the skin of the airbag, this web would be an integral part of or attached to the additional layer 16; if the additional layer was on the outside of the skin, this web would fill the hole in the Pass through the outer skin of the airbag and thus be part of or attached to the outer skin. The outer hole should be free of such a bridge to allow the bib to pass through.

the and show other ways how the inner hole can be stabilized: As in shown, can do that Hole not be circular, and as in As shown, a seam 19 may run around the hole. All of these stabilization measures can be used individually or in any combination and can also be used in ventilation devices without a tunnel and/or without a holding element of the type described.

In the embodiments shown, all connections are seams, which is often preferred, but it must be mentioned that other types of connections such as gluing or welding could also be used for at least some of the connections.

Reference List

5

air bag

10

outer skin

12

first opening (opening in the outer skin)

14

additional layer / blank for additional layer

16

second opening (opening in additional layer)

18

Bridge

19

seam around the opening

20

Cut for the bib / bib

20'

Cut for the bib

20a'

section of the main body

20b'-d'

Sections of the preceding part

21

bib / main part of the bib

21a

first edge

21b

second edge

21c

third edge

22

protruding part

22a

third edge

22b

fourth edge

25

Tunnel element / cutout for tunnel element

30

holding element

30'

strand of the holding element

31

first end area

31a

connection area

32

first end section

32a

first additional connection section

33

second end section

33a

second additional connection section

34

midrange

36

loop-shaped second end area

38

Inter-Retainer Connection

42-48

connections (seams)

50

fastener

52

fixed part

54

breakable part with pyrotechnic detonator

60

Housing

62

inflator

64

retaining ring

a

first angle

β

second angle

QUOTES INCLUDED IN DESCRIPTION

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

Patent Literature Cited

• WO 2020011634 A1 [0003]
• DE 102011014869 B4 [0016, 0024]

Claims (14)

An airbag (5) having a venting device, the airbag comprising: an outer skin (10) of the airbag, the outer skin (10) having a first opening (12), and an additional layer (14) having a second opening (16) that at least partially overlaps the first opening (12), a bib (20) that is located at least in sections between the outer skin (10) and the additional layer (14), a holding element (30) with a first end area (31), which is attached to the bib (20) at least in sections, a second end area (36) and a middle area (34) which connects the first end area (31) and the second end area (36), characterized in that at least part of the middle area ( 34) of the holding element (30) is guided in a tunnel which extends along a section of the outer skin (10). airbag after claim 1 , characterized in that the tunnel consists of the section of the outer skin (10) along which the tunnel extends and a tunnel element (25) which is fastened to the outer skin (10) of the airbag by means of a first fastening connection and a second fastening connection, is formed. airbag after claim 1 , characterized in that the tunnel is formed by a tube-forming tunnel element (25) which is attached to the outer skin. airbag after claim 3 , characterized in that the tunnel element (25) is closed by means of a locking connection. airbag after claim 4 , characterized in that the locking connection also connects the hose to the outer skin. airbag after claim 4 , characterized in that the hose is connected to the skin by an additional connection which is not the locking connection. Airbag according to one of the preceding claims, characterized in that at least the central region of the retaining element is made of at least one cord with a substantially circular or oval cross-section. Airbag after one of Claims 1 until 7 , characterized in that the first end region (31) comprises a first end section (32) and a second end section (33), both end sections (32, 33) being connected to the bib (20), the end sections (32, 33 ) preferably define a first angle greater than 0°, particularly preferably greater than 30°. airbag after claim 8 , characterized in that the bib (20) comprises a triangular body (21) having a first edge (21a) and a second edge (21b), the first end portion (32) extending along the first edge (21a) and the second End portion (33) extends along the second edge (21b). airbag after claim 8 or claim 9 , characterized in that the central area (34) consists of two parallel sections. airbag after claim 10 , characterized in that the holding element (30) comprises a common strand (30'), wherein the end sections (32, 33) are the end sections of the common strand (30) and the central part (34) consists of two parallel sections of the common strand ( 30') exists. Airbag after one of Claims 11 , characterized in that the second end region (36) is loop-shaped. Airbag after one of Claims 1 until 12 , characterized in that a stabilizing means is provided for the interior of the first and second holes, respectively, the stabilizing means comprising at least one of the following elements: a bridge crossing the opening, a seam surrounding the opening, and a non-circular cross-section the opening. Airbag module with the airbag according to one of Claims 1 until 13 and a fastener to which the second end portion is removably attached.

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