AIRBAG AND AIRBAG MODULE, METHOD FOR PRODUCING AN AIRBAG WOVEN AS A SINGLE PIECE, AND METHOD FOR PRODUCING AN AIRBAG MODULE

20220388473 · 2022-12-08

    Inventors

    Cpc classification

    International classification

    Abstract

    The invention describes an airbag (10), in particular a head side airbag (10) or a head-thorax side airbag, including at least two opposite fabric layers (12, 14) which form at least one inner wall (13) and one outer wall (15) of the airbag (10), wherein the airbag (10) is manufactured in one piece by a multi-layer weaving process in which the fabric layers (12, 14) are interwoven at least in a peripheral region (16), with a gas generator mount (18) for an external gas generator (20) being disposed in either of the two fabric layers (12, 14). The invention further describes an airbag module (8) comprising an airbag (10) according to the invention as well as a method for manufacturing a one-piece-woven airbag (10) and a method for manufacturing an airbag module (8).

    Claims

    1. An airbag (10), in particular a head side airbag (10) or a head-thorax side airbag, comprising at least two opposite fabric layers (12, 14) which form at least one inner wall (13) and one outer wall (15) of the airbag (10), wherein the airbag (10) is manufactured in one piece by a multi-layer weaving process in which the fabric layers (12, 14) are interwoven at least in a peripheral region (16), characterized in that wherein a gas generator mount (18) for an external gas generator (20) is disposed in one of the two fabric layers (12, 14).

    2. The airbag (10) according to claim 1, wherein the gas generator mount (18) comprises a sealing element (22).

    3. The airbag (10) according to claim 2, wherein the sealing element (22) is adhesively connected, in particular by ultrasonic welding, to the fabric layer (12, 14) comprising the gas generator mount.

    4. The airbag (10) according to claim 1, wherein the sealing element (22) includes a seal membrane (24) and a weld element (26) or a seal membrane (24) and a bonding element (28), the sealing element (22) being specifically a two-component part and the seal membrane (24) and the weld element (26) or the seal membrane (24) and the bonding element (28) consisting of different materials.

    5. The airbag (10) according to claim 4, wherein the seal membrane (24) is made of a silicone.

    6. The airbag (10) according to claim 4, wherein the weld element (26) is made of an airbag fabric or of the same material as the airbag fabric.

    7. The airbag (10) according to claim 1, wherein the airbag (10) comprises, in the peripheral region (16) adjacent to the gas generator mount (18), a mounting hole (30) in which the two opposite fabric layers (12, 14) are not interwoven, wherein the fabric layers (12, 14) are connected to each other and closed by ultrasonic welding or sewing in the area of the mounting hole (30), the mounting hole (30) being preferably disposed in a tubular extension (32) formed by the opposite fabric layers (12, 14).

    8. The airbag (10) according to claim 7, wherein a width (b) of the mounting hole (30) ranges from 40 mm to 100 mm, specifically from 60 mm to 80 mm.

    9. The airbag (10) according to claim 1, comprising at least one gas generator securing element (34, 36), in particular wherein the gas generator securing element (34, 36) is formed integrally with the airbag (10) or is secured, particularly sewn, to at least one of the fabric layers (12, 14) of the airbag (10).

    10. The airbag (10) according to claim 1, wherein the fabric layer (12, 14) forming the inner wall (13) and/or the outer wall (15) is coated at least in portions, preferably by an externally applied film.

    11. An airbag module (8) comprising an airbag (10) according to claim 1 and a gas generator (20) with a diffusor (40), the diffusor (40) being in the form of a T-diffusor (40) having a collecting portion (42) and a discharge portion (44), wherein the gas generator (20) is disposed outboard of the airbag (10), wherein the discharge portion (44) of the diffusor (40) is accommodated in the gas generator mount (18) of the airbag (10) so that discharge openings (46) of the diffusor (40) are disposed in an airbag interior (50) and the gas generator (20) is secured to the airbag (10) and/or to a module holder (48) via gas generator securing elements (34, 36, 38).

    12. A method for manufacturing a one-piece-woven airbag (10), in particular a one-piece-woven head side airbag (10) or a one-piece-woven head-thorax side airbag, comprising at least the following steps of: weaving an OPW airbag (10) by a multi-layer weaving process, the airbag (10) including at least two opposite fabric layers (12, 14) which form an inner wall (13) and an outer wall (15) and are connected to each other at least in a peripheral region (16), wherein the opposite fabric layers (12, 14) are not interwoven in a segment of the peripheral region (16) so that a mounting hole (30) is formed, positioning a sealing element (22) on a gas generator mount (18) disposed in one of the fabric layers (12, 14), establishing an adhesive connection between the sealing element (22) and the fabric layer (12, 14), in particular by ultrasonic welding or adhesive bonding, closing the mounting hole (30), in particular by ultrasonic welding.

    13. The method according to claim 12, wherein an opening (52) for the gas generator mount (18) is introduced in one of the fabric layers (12, 14) in the OPW airbag (10) already in the multi-layer weaving process or after the OPW airbag (10) has been woven, wherein the gas generator mount (18) is preferably introduced to the fabric layer (14) which forms the outer wall (15) of the OPW airbag (10).

    14. The method according to claim 12, wherein at least one gas generator securing element (34, 36) is attached to the OPW airbag (10).

    15. A method for manufacturing an airbag module (8), comprising at least the following steps of: providing a one-piece-woven airbag (10), according to claim 1, connecting a gas generator (20) to the one-piece-woven airbag (10) by introducing a discharge portion (44) of a diffusor (40), of the gas generator (20) into the gas generator mount (18), securing the airbag generator (20) to the airbag (10) and/or to a module holder (48) of the airbag module (8) by at least one gas generator securing element (34, 36, 38).

    16. A method for manufacturing an airbag module (8), comprising at least the following steps of: providing a one-piece-woven airbag (10) manufactured according to the method set forth in claim 12, connecting a gas generator (20) to the one-piece-woven airbag (10) by introducing a discharge portion (44) of a diffusor (40), of the gas generator (20) into the gas generator mount (18), securing the airbag generator (20) to the airbag (10) and/or to a module holder (48) of the airbag module (8) by at least one gas generator securing element (34, 36, 38).

    Description

    BRIEF DESCRIPTION OF THE DRAWINGS

    [0033] Further advantages, features and details of the invention will be apparent from the following description of a non-limiting embodiment as well as by means of the drawings, wherein

    [0034] FIG. 1 a) shows a schematic representation of an embodiment of an airbag according to the invention and b) shows a detail view of the airbag in the area of a gas generator mount,

    [0035] FIG. 2 shows a schematic front view of the area of a gas generator mount of an embodiment of an airbag module according to the invention,

    [0036] FIG. 3 shows a schematic lateral view of the area of the gas generator mount of the airbag module according to FIG. 2,

    [0037] FIG. 4 shows a perspective view of a cutout of an airbag according to the invention in the area of a gas generator mount as well as a gas generator associated with the gas generator mount,

    [0038] FIG. 5 shows an enlarged perspective representation of the gas generator mount of the airbag according to the invention and of the associated gas generator according to FIG. 4,

    [0039] FIG. 6 shows a schematic top view of the gas generator mount of the airbag according to the invention and of the associated gas generator according to FIG. 4,

    [0040] FIG. 7 shows a schematic sectional view across the gas generator mount of the airbag according to the invention and the associated gas generator according to FIG. 6,

    [0041] FIG. 8 shows a schematic sectional view across a T diffusor of the gas generator of FIG. 4,

    [0042] FIG. 9 shows a schematic representation of a gas generator mount when positioning and connecting a sealing element on and, resp., to the gas generator mount of an airbag according to the invention by a mounting aid,

    [0043] FIG. 10 shows a sectional view across the gas generator mount along the line X-X according to FIG. 9,

    [0044] FIG. 11 shows a schematic exploded view of the gas generator mount, the sealing element and the mounting aid according to FIG. 9,

    [0045] FIG. 12 shows a schematic representation of a gas generator mount when positioning and connecting a sealing element on and, resp., to the gas generator mount of an airbag according to the invention by an alternative mounting aid, and

    [0046] FIG. 13 shows a perspective schematic representation of the gas generator mount according to FIG. 12.

    DESCRIPTION

    [0047] FIGS. 1a and 1b illustrate an airbag 10 according to the invention that is configured as a head side airbag 10 in the shown embodiment.

    [0048] The airbag 10 comprises at least two opposite fabric layers 12 and 14 forming at least one inner wall 13 and one outer wall 15 of the airbag 10. The airbag 10 is formed integrally by a multi-layer weaving process in which the fabric layers 12 and 14 are interwoven at least in a peripheral region 16. The dashed double line in FIG. 1b constitutes the delimitation of the peripheral region 16 from which the fabric layers 12 and 14 are not interwoven so as to form an airbag interior 50.

    [0049] The airbag 10 shown in FIG. 1a further comprises partition portions 54 in which the two fabric layers 12 and 14 are equally interwoven so that the airbag 10 cannot be inflated in this area.

    [0050] The shown airbag 10 moreover comprises plural airbag securing portions 82 provided for securing the airbag 10 and, resp., an airbag module 8 including the airbag 10 in a vehicle.

    [0051] FIG. 1b illustrates that the airbag 10 shown here has a gas generator mount 18 in the outer wall 15 formed by the fabric layer 14. The gas generator mount 18 comprises a sealing element 22 which in this case is adhesively connected, for example by ultrasonic welding or adhesive bonding, to the fabric layer 14 comprising the generator mount 18.

    [0052] For connecting the sealing element 22 to the fabric layer 14, the airbag 10 comprises, in the peripheral region 16 adjacent to the gas generator mount 18, a mounting hole 30 in which the two opposite fabric layers 12 and 14 are not interwoven. The fabric layers 12 and 14 can be connected to each other in the area of the mounting hole 30 by ultrasonic welding or sewing, for example, and the mounting hole 30 can thus be closed. In the airbag 10 shown here, the mounting hole 30 is disposed in a tubular extension 32 formed by the opposite fabric layers 12 and 14. The mounting hole 30 can be used in the airbag 10 especially for introducing a mounting aid 66 (see FIGS. 9 to 13) for securing the sealing element 22 to the gas generator mount 18, when the airbag 10 is manufactured. To this end, the mounting hole may have a width b from 40 mm to 100 mm, in particular from 60 mm to 80 mm.

    [0053] The airbag 10 further comprises gas generator securing elements 34 and 36. The gas generator securing element 36 is formed integrally with the airbag 10 in the shown embodiment. A gas generator securing element 36 of this type formed integrally with the airbag 10 is already manufactured in one piece along with the fabric layers 12 and 14 when the airbag 10 is manufactured in the multi-layer weaving process. The gas generator securing element 36 shown here is configured as a loop adjacent to the peripheral region 16 for receiving a tubular gas generator 20.

    [0054] The further gas generator securing element 34 shown here is secured to the airbag 10 via fixing seams 58. FIG. 1a illustrates the gas generator securing element 36 in a state for securing an external gas generator 20 in which the gas generator securing element 36 is secured to the airbag 10 via fixing seams 58 both in a peripheral region 16 and in a partition portion 54 (see also FIGS. 2 and 3 in which also the gas generator 20 is illustrated).

    [0055] In FIG. 1b, the gas generator securing element 36 (shown in dashed line) is shown in a state before securing the external gas generator 20 and is connected to the airbag 10 only in the peripheral region 16 via fixing seams 58.

    [0056] As an alternative to the securing via the fixing seams 58, the airbag 10 may be provided to include, in the peripheral region 16, airbag fixing element mounts 56 which are introduced to the peripheral region as slot openings, for example. In such embodiment, the gas generator securing element 36 is threaded through the slot-type airbag fixing elements 36, for example, for securing in the peripheral region 16 of the airbag 10. The one end of the gas generator securing element 36 may be connected, e.g., to the gas generator 20 and the other end may be connected to the airbag 10, in particular in the area of a partition portion 54, via a fixing seam 58, for example.

    [0057] The FIGS. 2 and 3 show the securing of the gas generator 20 to the airbag 10 in the area of the gas generator mount 18 in an enlarged representation.

    [0058] The gas generator 20 is disposed outboards on the airbag 10 of the airbag module 20 so that the discharge portion 44 of the diffusor 40 is accommodated in the gas generator mount 18 of the airbag 10. The discharge openings 46 of the discharge portion 44 are disposed in the airbag interior 50 so that, when the airbag module 8 is activated, the outflowing gas can fill the airbag 8.

    [0059] For securing the gas generator 20 outboards on the airbag 10 according to the invention as set forth in the embodiment of FIGS. 2 and 3, initially the discharge portion 44 of the T diffusor 40 of the gas generator 20 is put through a diffusor mount 84 on the gas generator securing element 34, before the discharge portion 84 is inserted into the dedicated gas generator mount 18 so that the gas generator securing element 34 encompasses the gas generator 20 at the axial end 64 in the area of the diffusor 40, see FIG. 3. Accordingly, the gas generator securing element 34 can be secured to the airbag via the fixing seams 58 in the area of the edge 16 already before inserting the gas generator 20 or after inserting the gas generator 20.

    [0060] In order to safely fix the discharge portion 44 of the gas generator 20 in the gas generator mount 18, the gas generator securing element 34 is tightened once more over the axial end 64 of the gas generator 20 and, in the shown embodiment, is secured to the airbag 10 via a fixing seam 58 in the area of a partition portion 54. Securing of the gas generator securing element 34 can also be performed via the fixing seam 58 in the area of the partition portion already before inserting the gas generator 20 or only after inserting the gas generator 20.

    [0061] In the illustrated embodiment, the gas generator securing element 34 is connected to a module holder 48 of the airbag module 8 via a module holder mount 60 in the area of a gas generator securing element portion 35.

    [0062] For minimizing the load upon the closing seam 86 of the mounting hole 30 which is particularly configured as a weld seam produced by ultrasonic welding, the tubular extension 32 is wrapped, when the gas generator 20 is secured to the airbag 10, around the gas generator 20 such that it is disposed between the gas generator 20 and the module holder 48.

    [0063] FIG. 2 illustrates that, in this case, moreover a gas generator securing element 38 configured as clip or clamp which additionally fixes the gas generator securing element portion 35 and the module holder 48 to the airbag 10 and fixes the tubular extension 32 between the gas generator 20 and the module holder 48 is used to secure the gas generator 20 to the airbag 10.

    [0064] FIGS. 4 to 7 illustrate the area of the gas generator mount 18 of the airbag 10 of an airbag module 8 according to the invention in an enlarged representation. FIG. 4 illustrates the airbag 10 in an exploded view for better illustration.

    [0065] FIG. 4 shows that the gas generator 20 comprises a gas generator securing element 39 configured as a bolt welded to the gas generator. The gas generator can be secured to a module holder 48 (see FIG. 2) of the airbag module 8 via the gas generator securing element 39.

    [0066] The sealing element 22 illustrated in FIGS. 4 to 7 is adhesively connected to the fabric layer 14 constituting the outer wall 15 by ultrasonic welding. The sealing element includes a seal membrane 24 for sealing the connection between the airbag 10 and the discharge portion 44 of the gas generator 20 in the area of the gas generator mount 18. In order to achieve proper sealing, the seal membrane is preferably made of silicone. The sealing element is connected to the fabric layer 14 via a welded portion 26. In order to obtain a stable welded connection, the weld element 26 is preferably made of the same material as the fabric layers 12 and 14 of the airbag 10. The weld portion can consist particularly of a film that is made of the same material as the fabric layers 12 and 14, or can be an airbag fabric.

    [0067] In order to pass, upon activation of the gas generator 20, the gas from the external gas generator 20 into the airbag interior 50, the gas generator 20 includes a diffusor 40 in the form of a T diffusor 40.

    [0068] The diffusor 40 (see also FIG. 8) comprises a collecting portion 42 and a discharge portion 44 that protrudes or projects radially from the collecting portion 42. The diffusor 40 encloses the gas generator 20 at the axial end 64 in which the outflow area 62 including outflow openings is disposed. Accordingly, a longitudinal axis LG of the gas generator 20 coincides with a longitudinal axis LS of the collecting portion 42 of the diffusor 40 (see FIG. 6).

    [0069] In the state disposed on the gas generator 20, the collecting portion 42 encloses with a collecting chamber 43 the outflow openings of the outflow area 62 of the gas generator 20. The gas radially exiting the gas generator 20 is passed into the discharge passage 45 of the discharge portion 44 via the collecting chamber 43. In the discharge portion 44, the radial gas flow direction GR is deflected to an axial gas flow direction GA before it flows out of the discharge openings 46 from the discharge portion 44 into the airbag interior 50.

    [0070] It is further apparent from FIG. 8 that the diffusor 40 may include one or more sealing element mounts 41 for accommodating one or more sealing elements 47. FIG. 8 moreover shows that the diffusor 40 is referred to as T diffusor 40, as the longitudinal axis LA of the discharge portion 44 and the longitudinal axis LS of the collecting portion 42 are aligned with each other in T-shape. As a matter of course, it may also be provided that the longitudinal axis LA of the discharge portion 44 is arranged vis-à-vis the longitudinal axis LS of the collecting portion 42, and thus also the discharge portion 44 vis-à-vis the collecting portion 42, at an angle not equal to 90°. As an alternative to the shown configuration as a separate component, the diffusor and the gas generator housing may be formed in one piece (not shown).

    [0071] FIGS. 9 to 13 schematically illustrate devices for establishing the adhesive connection between either of the fabric layers 12 or 14 and the sealing element 22. A detailed representation of the area of the airbag 10 adjacent to the gas generator mount 18 which may include, inter alia, the mounting hole 30 and/or the tubular extension 32, is dispensed with for reasons of clarity.

    [0072] The sealing element 22 shown in FIGS. 9 to 11 comprises a seal membrane 24 and a bonding element 28. The sealing element 22 can be adhesively connected to either of the fabric layers 12 or 14, in this case the fabric layer 14, via the bonding element 28 by adhesive bonding.

    [0073] For establishing such an adhesive bonded joint, a heat-sealing technique can be utilized, for example.

    [0074] For this purpose, the sealing element 22 is placed in a sealing element positioning mount 72 of a mounting aid 66 which is a positioning tool 68 of a heat-sealing device 74 in this case. After that, the positioning tool 68 is inserted into the airbag interior 50 through the mounting hole 30, and the sealing element 22 is positioned relative to an opening 52 of the gas generator mount 18 so that an axis of rotation of the sealing element 22 is disposed in the center of the opening 52. Then the sealing element 22 is pressed by the positioning tool 68 at said position from inside against the fabric layer 14 so as to connect the sealing element 22 to the fabric layer 14. For establishing the bonded joint, on the outer face, a heating die 70 is pressed against the fabric layer 14 and the positioning tool 68 with the sealing element 22 located in the airbag interior 50. Subsequently, the bonding element 28 can be heated via the heating die 70 so that the bonding element 28 of the sealing element can be adhesively connected to the fabric layer 14.

    [0075] The sealing element 22 shown in FIGS. 12 and 13 includes a seal membrane 24 and a weld element 26. The sealing element 22 can be adhesively connected, via the weld element 28, to either of the fabric layers 12 or 14, in this case the fabric layer 14, by welding, specifically ultrasonic welding.

    [0076] For establishing such an adhesive welded joint, an ultrasonic welding technique can be utilized, for example.

    [0077] For this purpose, the sealing element 22 is placed in a sealing element positioning mount 72 of a mounting aid 66 which is in the form of a converter 76 of an ultrasonic welding device 80 in this case. Subsequently, the converter 76 is inserted into the airbag interior 50 via the mounting hole 30, and the sealing element 22 is positioned relative to an opening 52 of the gas generator mount 18 so that an axis of rotation of the sealing element 22 is disposed in the center of the opening 52. After that, the sealing element 22 is pressed, in this position, from inside against the fabric layer 14 by the converter 76 so as to connect the sealing element 22 to the fabric layer 14. For establishing the ultrasonic welded connection, on the outside a sonotrode 78 of the ultrasonic welding device 80 is pressed against the fabric layer 14 and the converter 76 with the sealing element 22 located in the airbag interior 50. Subsequently, an ultrasonic vibration can be generated via the converter 76 and can be transmitted to the sonotrode 78, thus causing the welded element 26 and the fabric layer 14 to be heated in this area and to be adhesively connected to each other by fusion, for example.