Gasbag module with gas distribution element

Abstract

Gas bag module comprising a gas bag (12), a gas generator (14), and a gas distribution element (16) for distributing the gas flowing from the gas generator (14) in different flow directions, wherein the gas distribution element (16) is designed such that it is deformed by the pressure exerted by the outflowing gas in such a way as to influence the distribution of the gas to the different flow directions, wherein the gas distribution element (16) directs the gas in two opposite flow directions, characterized in that the gas distribution element (16) is slotted and the gas distribution element (16) is a sleeve with a first gas outlet surface (26) and an opposite second gas outlet surface (28), wherein the sleeve is deformable into a cone by the gas pressure, further characterized by an auxiliary element (30) which ensures a conical shape of the gas bag wall in the area of ​​the gas distribution element (16).on which the gas distribution element (16) can be supported, or that an auxiliary element (30) is arranged in the area of ​​the gas distribution element (16), which consists of at least one layer of fabric (32) on which the gas distribution element (16), deformed into a cone, can be supported, wherein the auxiliary element (30) is inclined relative to the longitudinal axis of the gas generator (14) or the gas distribution element (16).

Description

[0001] The invention relates to a gas bag module comprising a gas bag, a gas generator and a gas distribution element for distributing the gas flowing out of the gas generator in different flow directions.

[0002] A gas distribution element associated with a gas generator serves to control the gas flow from the gas generator into the gas bag. In particular, the gas supplied by the gas generator can thus be distributed selectively to different inflatable chambers of the gas bag. In addition, a gas distribution element can prevent the direct contact of hot gas with the wall or seams of the gas bag.

[0003] From WO 2005 / 028264 A1, a gas bag module with a gas distribution element is known that enables the gas flow to be divided into two opposite directions in order to simultaneously fill two chambers of a side gas bag. The hollow cylindrical gas distribution element is mounted on a tubular gas generator and has two bridge-like radial protrusions. An opening is formed at each axial end of the protrusions. Due to the different sizes of the openings, a larger quantity of gas flows into one chamber than into the other.

[0004] DE 10 2007 028 682 A1 discloses a generic gas bag module comprising a tubular gas generator and a rigid sleeve-like gas distribution element made of plastic, which has a mounting section for attaching the gas distribution element to the gas bag. In a gas-conducting section of the gas distribution element that completely surrounds the gas generator in the circumferential direction and is closed, several internal gas channels are formed that guide the gas supplied by the gas generator in axially opposite directions. The gas channels can be formed, in particular, by incorporating ribs into the gas-conducting section.

[0005] DE 10 2004 038 459 B4 discloses a gas bag module in which a deformable band wound around the gas generator unfolds when the gas generator is activated and opens under the pressure of the gas until it rests against the inner walls of an inner gas bag arranged inside an outer gas bag. The band serves, in particular, to protect the outer gas bag and the vehicle occupants from excessive heat exposure.

[0006] The object of the invention is to create a cost-effective, compact and flexible solution for gas distribution in a gas bag module.

[0007] This is achieved by a gas bag module of the type mentioned above, in which the gas distribution element is designed such that it is deformed by the pressure exerted by the outflowing gas, thereby influencing the distribution of the gas to the different flow directions. With the invention, the distribution of the gas flow of a standard gas generator can be individually adjusted, which until now has only been possible to a very limited extent. The invention is based on the finding that the pressure of the gas flowing out of the gas generator can be used to selectively deform the gas distribution element in order to influence the gas distribution as desired. The invention also has the advantage that, due to the deformation (expansion) of the gas distribution element, its stress is significantly reduced.

[0008] The invention is preferably applicable to a side gasbag module with a side gasbag comprising a pelvic chamber and a thoracic chamber, or a thoracic chamber and a head chamber, which are inflated to different degrees of rigidity. For such gasbags, tubular gas generators are generally used, the gas supplied by which is divided between the two chambers by means of the gas distribution element. A fundamentally simple design of the gas distribution element is possible with a corresponding design of the gasbag (arrangement of the chamber inflation openings) in that the gas distribution element directs the gas in two opposite flow directions.

[0009] According to the preferred embodiment of the invention, the gas distribution element is a sleeve with a first gas outlet surface and an opposing second gas outlet surface, wherein the sleeve is deformable into a cone by the gas pressure. The conical shape of the gas distribution element allows the gas outlet surface for one of the gas chambers to be enlarged more, so that more gas can be directed into this chamber than when using a rigid sleeve as the gas distribution element.

[0010] The conical shape of the gas distribution element can be achieved, for example, by a slotted gas distribution element. Such a gas distribution element can be expanded radially, whereby the expansion at an axial end of the The gas distribution element can be more restricted than at the other axial end.

[0011] For this purpose, a special auxiliary element can be provided which ensures a conical shape of the gas bag wall in the area of ​​the gas distribution element, against which the gas distribution element can support the ment.

[0012] A seam of the gas bag is suitable, for example, as an auxiliary element. According to a first embodiment of the invention, the auxiliary element is part of a separating seam that separates two inflatable chambers of the gas bag from each other. Such a seam is already present in the gas bag and can be designed or supplemented according to the requirements without significant technical effort, in particular without additional components or work steps.

[0013] Alternatively, an auxiliary element can also be formed by additionally inserted layers of fabric, the shape of which is adapted to the desired gas distribution. It is also possible to form the auxiliary element in the form of a belt or a retaining strap.

[0014] Further features and advantages of the invention will become apparent from the following description and from the accompanying drawings, to which reference is made. The drawings show:

[0015] Fig. 1 shows a gasbag module according to the invention with an uninflated, flat-lying gasbag;

[0016] Fig. 2 shows a detailed enlargement from Fig. 1 in the installed state;

[0017] Fig. 3 shows the detailed enlargement according to Fig. 2 in the activated state of the gas generator;

[0018] Fig. 4 shows a second embodiment of the gas bag module according to the invention;

[0019] Fig. 5 shows a detailed view of the auxiliary element according to Fig. 4 and

[0020] Fig. 6 shows a detailed view of the embodiment according to Fig. 4.

[0021] The gas bag module 10 shown in Fig. 1 comprises a gas bag 12, a gas generator 14 and a gas distribution element 16.

[0022] The gas bag 12 consists of two layers of fabric lying flat on top of each other (in the uninflated state), which are joined by seams along their circumference. Only one of the two layers of fabric of the gas bag 12 is shown in Fig. 1. The gas bag 12 is divided into two inflatable chambers 20 and 22 by a dividing seam 18. The dividing seam 18 ends in an inlet area 24 of the gas bag 12, in which the gas generator 14 is housed.

[0023] The two fabric layers of the gas bag can consist of a single piece of fabric, as shown in Fig. 1, which is folded along an axis of symmetry and whose edges are sewn together. The two fabric layers can also be separate pieces that are sewn together along their entire circumference.

[0024] In the case shown, the gas generator 14 is an elongated tube gas generator, which is arranged such that a gas outlet area of ​​the gas generator 14 faces one of the two chambers, here the chamber 20.

[0025] The gas distribution element 16 is fitted over the outlet area of ​​the gas generator 14. The gas distribution element 16 is a sleeve made of metal or plastic, in particular a polymer, which serves to distribute the gas flowing out of the gas generator 14 to the two chambers 20, 22. For this purpose, gas outlet surfaces 26 and 28 are provided at the two axial ends of the gas distribution element 16. In addition, the gas distribution element 16 protects the fabric of the gas bag 12 from the hot gas and the hot particles contained in the gas stream.

[0026] The gas bag module 10 with the gas bag 12 designed according to Fig. 1 and the gas generator 14 can, for example, be used as A side-impact protection device for a vehicle occupant is to be installed in the backrest of a vehicle seat. The lower chamber 20 is in this case a pelvic chamber, the upper chamber 22 a thoracic chamber, whereby the pelvic chamber 20 is to be inflated to a higher pressure than the thoracic chamber 22.

[0027] However, the invention is not limited to the illustrated form of the gas bag 12 and the described purpose. Rather, the invention can be used in any form of gas bag with one or more inflatable chambers, including those with woven or glued connections, as well as in three-dimensional gas bags made from any number of cut parts.

[0028] The gas generator 14 is designed to have a main outflow direction; in the illustrated case, this direction points towards the lower chamber 20. Furthermore, in the installed state of the gas distribution element 16, the gas outlet area 26 facing the lower chamber 20 is larger. To nevertheless provide a control option that allows an increase in the gas flow into the upper chamber 22, the gas distribution element 16 has a special design described below.

[0029] The sleeve-like gas distribution element 16 is, in cross-section, essentially circular; however, it is slotted longitudinally (axially). The gas distribution element 16 thus has the The gas distribution element 16 is shaped like a "band" wound around the gas outlet area of ​​the gas generator 14, which is elastically deformable in the radial direction. This design allows the gas distribution element 16 to expand radially under the pressure of the gas flowing from the gas generator 14, thus increasing the size of the gas outlet areas 26, 28 of the gas distribution element 16. This radial expansion simultaneously reduces the stress on the gas distribution element 16 caused by the hot gas and the entrained particles.

[0030] However, the expansion of the gas distribution element 16 is limited. The shape that the gas distribution element 16 acquires during its expansion is selectively influenced by an auxiliary element 30. As can be seen in Fig. 3, the gas distribution element 16 expands into a cone. In doing so, one of the gas outlet surfaces, here surface 28, is enlarged to a greater extent than the other, here surface 26. The gas can flow out of the gas distribution element 16 through both gas outlet surfaces 26, 28 in the direction of chamber 20 and chamber 22, respectively; however, the amount of gas differs due to the different sizes of the gas outlet surfaces 26, 28.

[0031] In the illustrated embodiment according to Fig. 1, the auxiliary element 30 is the separating seam 18, more precisely the part of the separating seam 18 that ends in the inlet area 24 of the gas bag 12. This part of the separating seam 18 is designed such that it provides a conical shape to the gas bag wall in the area of ​​the gas distribution element 16, against which the gas distribution element 16 is supported. This can be achieved, for example, by seam sections that are inclined relative to the longitudinal axis of the gas generator 14 or the gas distribution element 16.

[0032] In the case of a side gas bag, the gas outlet surface 28 of the gas distribution element 16 facing the lower chamber 22 can thus be specifically enlarged in order to introduce more gas into this lower chamber 22.

[0033] Other auxiliary elements besides the separating seam 18 can also be provided to achieve the desired shape of the gas distribution element 16 when inflating the gas bag 12. In particular, the auxiliary element can be a strap or a retaining strap that is attached to the gas bag 12 in the The area of ​​the gas distribution element 16 has a conical shape against which the gas distribution element 16 can be supported. A retaining strap or an additional belt arranged between the two chambers 20, 22 can also directly hold the gas distribution element 16 in the desired shape.

[0034] Another possible embodiment of the auxiliary element is shown in Figures 4 to 6. Here, the auxiliary element is formed by an additional layer of fabric that loops around the gas distribution element. The additional layer of fabric 32 is mirror-symmetrical and, when flattened, has the shape of an H. The two longitudinal legs 34 and 36 are inclined relative to the longitudinal axis of symmetry 38 by the angle α, which corresponds to the cone angle of the gas distribution element to be set. During assembly or sewing of the airbag, the additional layer of fabric 32 is folded along the axis of symmetry 38. The longitudinal legs 34 and 36, which then lie one above the other, are inserted between the layers of fabric of the airbag that lie one above the other in the area of ​​the generator and sewn to its edge seam. The resulting loop, when the gas bag module is fully assembled, encompasses the generator and the gas distribution element.

[0035] As gas flows out, the gas distribution element 16 expands. The expansion is limited by the additional tissue layer 32, as the wall of the gas distribution element conforms to the additional tissue layer. In this process, the gas distribution element assumes a conical shape, the cone angle of which corresponds to the cone angle of the tissue layer. QUOTES INCLUDED IN THE DESCRIPTION

[0036] This list of documents cited by the applicant was generated automatically and is included solely for the convenience of the reader. The list does not form part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0037] - WO 2005 / 028264 A1

[0003] - DE 102007028682 A1

[0004] - DE 102004038459 B4

[0005]

Claims

[1] Gas bag module with a gas bag (12), a gas generator (14) and a gas distribution element (16) for distributing the gas flowing out of the gas generator (14) in different flow directions, characterized in that the gas distribution element (16) is designed in such a way that it is deformed by the pressure exerted by the outflowing gas in such a way that the distribution of the gas on the different flow directions is influenced. [2] Gas bag module according to claim 1, characterized in that the gas distribution element (16 ) directs the gas in two opposite flow directions. [3] Gas bag module according to claim 1 or 2, characterized in that the gas distribution element (16 ) is a sleeve with a first gas outlet surface (26 ) and an opposite second gas outlet surface (28 ), wherein the sleeve is deformable to a cone by the gas pressure. [4] Gas bag module according to claim 3, characterized in that the gas distribution element (16 ) is slotted. [5] Gas bag module according to claim 3 or 4, characterized by an auxiliary element (30) which provides a conical shape to the gas bag wall in the area of ​​the gas distribution element (16) against which the gas distribution element (16) can be supported. [6] Gas bag module according to claim 5, characterized in that the auxiliary element (30 ) is inclined relative to the longitudinal axis of the gas generator (14 ) or the gas distribution element (16 ). [7] Gasbag module according to claim 5 or 6, characterized in that the auxiliary element (30 ) is a seam (18 ). [8] Gasbag module according to claim 7, characterized in that the auxiliary element (30 ) is part of a separating seam (18 ) that separates two inflatable chambers (20 , 22 ) of the gasbag (12 ) from each other. [9] Gas bag module according to claim 3 or 4, characterized in that an auxiliary element is arranged in the area of ​​the gas distribution element, which consists of at least one layer of fabric (32) on which the gas distribution element, deformed into a cone, can be supported. [10] Gas bag module according to claim 9, characterized in that the additional fabric layer (32 ) is formed in the form of a conically shaped loop and is sewn to the air bag. [11] Gasbag module according to claim 5, characterized in that the auxiliary element is a belt or a safety strap. [12] Gas bag module according to one of the preceding claims, characterized in that the gas distribution element (16 ) is made of metal. [13] Gas bag module according to one of claims 1 to 9, characterized in that the gas distribution element (16 ) is made of plastic, in particular a polymer.

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