AIRBAG MODULE, VEHICLE SEAT HAVING AN AIRBAG MODULE, AND VEHICLE

Abstract

The invention relates to an airbag module (12) comprising a restraint airbag (30) which is inflated in a situation of restraint and, in an inflated state, has a restraining effect on an occupant (16), and at least one backup member (36, 36a, 36b) which, in a restraining state, is at least in portions in contact with the inflated restraint airbag (30) and is configured so that it backs the restraint airbag (30) and in particular absorbs a force (F) applied to the restraint airbag (30) by contacting a vehicle occupant (16), wherein, in the inflated state, the restraint airbag (30) is interposed between the backup member (36, 36a, 36b) and the vehicle occupant (16), wherein the backup member (36, 36a, 36b) is arranged, in an initial state, on or in the airbag module. The invention also relates to a vehicle seat and a vehicle comprising an airbag module according to the invention.

Claims

1-21. (canceled)

22. An airbag module (12) comprising a restraint airbag (30) which is inflated in a situation of restraint and, in an inflated state, has a restraining effect on an occupant (16), and at least one backup member (36, 36a, 36b) which, in a restraining state, is at least in portions in contact with the inflated restraint airbag (30) and is configured to back the restraint airbag (30) and particularly absorb a force (F) applied to the restraint airbag (30) by contacting a vehicle occupant (16), wherein the restraint airbag (30) in the inflated state is interposed between the backup member (36, 36a, 36b) and the vehicle occupant (16), the backup member (36, 36a, 36b) being arranged on or in the airbag module in an initial state.

23. The airbag module (12) according to claim 22, wherein the backup member is accommodated inside the airbag module (12), in particular in a module housing (28).

24. The airbag module (12) according to claim 22, wherein the backup member is in the form of an element separate from the airbag module.

25. The airbag module (12) according to claim 22, wherein in the restraining state the backup member (36, 36a, 36b) is arranged in the area of an exit opening (42) of the restraint airbag (30) out of the airbag module (12).

26. The airbag module (12) according to claim 22, wherein in an initial state the at least one backup member (36, 36a, 36b) is arranged in a holder (38), wherein a transfer mechanism (40) is provided for moving, in a situation of restraint, the at least one backup member (36, 36a, 36b) out of the holder (38) into the restraining state.

27. The airbag module (12) according to claim 26, wherein the transfer mechanism (40) is formed so that the backup member (36, 36a, 36b) is firmly fixed to an outer wall (45) of the restraint airbag (30), or in that the transfer mechanism (40) comprises a gas generator (32; 46) or a mechanical drive.

28. The airbag module (12) according to claim 22, wherein at least one backup member (36) is provided that is a dimensionally stable backup member (36a) in the form of a component which is rigid at least in portions in the restraining state.

29. The airbag module (12) according to claim 28, wherein at least portions of the dimensionally stable backup member (36a) are made of an auxetic material.

30. The airbag module (12) according to claim 28, wherein the dimensionally stable backup member (36a) is arranged so that it is linearly displaced, swiveled or rotated for being transferred from the initial state to the restraining state.

31. The airbag module (12) according to claim 28, wherein the dimensionally stable backup member (36a) comprises a flexible portion (56, 60) which, in the initial state, is folded and arranged in the holder (38) and which unfolds when it is transferred to the restraining state.

32. The airbag module (12) according to claim 22, wherein at least one backup member (36) is provided which is an inflatable backup airbag (36b).

33. The airbag module (12) according to claim 11, wherein the backup airbag (36b) is filled at a higher internal pressure than the restraint airbag (30).

34. The airbag module according to claim 32, wherein there are provided plural backup airbags (36b) which mutually back each other.

35. The airbag module (12) according to claim 22, wherein at least one backup member (36) is configured as a backup chamber (36c) which forms an inflatable portion of the restraint airbag (30), wherein the backup chamber (36c) is filled at a higher internal pressure than a restraint chamber (30′) of the restraint airbag (30).

36. The airbag module (12) according to claim 28, wherein at least one backup member (36) configured as a dimensionally stable backup member (36a) as well as at least one backup member (36) in the form of a backup airbag (36b) and/or a backup chamber (36c) are provided, wherein the backup airbag (36b) and/or the backup chamber (36c) is/are arranged, in the restraining state, between the restraint airbag (30) or between the restraint chamber (30′) of the restraint airbag (30) and the dimensionally stable backup member (36a).

37. The airbag module (12) according to claim 22, wherein at least one backup member (36) is provided that includes at least two leg elements (78) which are arranged at least in portions substantially V-shaped relative to each other and between which at least one cross strut (80) connecting the leg elements (78) is arranged.

38. The airbag module (12) according to claim 37, wherein plural cross struts (80) are interposed between the leg elements (78), wherein, in the cross-section of the backup member (36), the cross struts (80) are arranged especially in a rung-like manner between the leg elements (78) and the length of the cross struts (78) is reduced toward the joint tip (86).

39. The airbag module (12) according to claim 37, wherein the leg elements (78) are configured as inflatable elements and/or as resiliently flexible elements and the cross struts (80) are configured as inflatable elements and/or as dimensionally stable elements.

40. A vehicle seat (10), comprising at least one airbag module (12) according to claim 22, wherein the restraint airbag (30) is inflated in a situation of restraint and, in an inflated state, has a restraining effect on the occupant (16) on a contact area (14) of the vehicle seat (10), wherein the at least one backup member (36, 36a, 36b) in a restraining state is in contact, at least in portions, with the inflated restraint airbag (30) and can exert a force (F) directed toward the contact area (14) on the restraint airbag (30), wherein the restraint airbag (30) is located between the contact area (14) and the backup member (36, 36a, 36b).

41. The vehicle seat according to claim 40, wherein there are provided at least two airbag modules (12) which are arranged on each side of the contact area (14) and which are arranged on the seat base (18), on the backrest (22) or on the headrest (26).

42. A vehicle comprising at least one airbag module (12) according to claim 22.

43. A vehicle comprising a vehicle seat according to claim 40.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0088] In the following, the invention will be described in detail by means of plural embodiments with reference to the attached drawings, wherein:

[0089] FIG. 1 shows a vehicle seat according to the invention as set forth in a first embodiment;

[0090] FIG. 2 shows an airbag module according to the invention as set forth in a first embodiment, with the backup member being illustrated in the initial state;

[0091] FIG. 3 shows the airbag module of FIG. 2, with the backup member being illustrated in the restraining state;

[0092] FIGS. 4 to 6 show an airbag module according to the invention as set forth in a second embodiment in different states before and during activation thereof;

[0093] FIGS. 7 to 12 shows vehicle seats according to the invention as set forth in further embodiments in each of a normal operating situation and a situation of restraint;

[0094] FIGS. 13 to 48 show vehicle seats according to the invention as set forth in further embodiments comprising different dimensionally stable backup members in different representations;

[0095] FIGS. 49 to 52 show vehicle seats according to the invention as set forth in further embodiments comprising different backup airbags, in different representations;

[0096] FIG. 52a shows an airbag module according to the invention as set forth in a further embodiment comprising a backup member in the form of a backup airbag;

[0097] FIG. 53 shows a vehicle seat according to the invention as set forth in a further embodiment comprising plural backup airbags;

[0098] FIGS. 54 to 67 show vehicle seats according to the invention as set forth in further embodiments comprising different combinations of dimensionally stable backup members and backup airbags in different representations;

[0099] FIG. 68 shows an airbag module according to the invention as set forth in a further embodiment comprising a backup member in the form of a backup chamber;

[0100] FIGS. 69 to 71 show an airbag module according to the invention as set forth in a further embodiment, wherein different stages of a further backup member between an initial state and a restraining state are illustrated; and

[0101] FIGS. 72 and 73 show vehicle seats according to the invention as set forth in further embodiments, wherein the interaction of two opposite restraint airbags is illustrated.

DESCRIPTION

[0102] FIG. 1 shows a vehicle seat 10 comprising one or more airbag module(s) 12 integrated in the vehicle seat 10 as set forth in a first embodiment. In the interior of a vehicle (not shown) several vehicle seats 10 may be arranged.

[0103] The airbag module 12 may be mounted at different points on the vehicle seat 10 as will be also discussed in the following with reference to FIGS. 7 to 12.

[0104] The vehicle seat 10 has a contact area 14 which a vehicle occupant 16 contacts when he/she is seated in the vehicle seat 10. The contact area 14 is composed of a seat base 18, the area 20 of a backrest 22 and the area 24 of a headrest 26 (see also FIG. 7).

[0105] The airbag module(s) 12 is/are arranged on the side of the contact area 14 and is/are positioned in the area of the seat base 18, the backrest 22 or the headrest 26.

[0106] In FIGS. 2 and 3, the airbag module 12 according to a first embodiment is shown. The airbag module 12 in this case is arranged in the vehicle seat 12 in a holder not shown in detail, but it could also be provided, independently of a vehicle seat, at any other suitable position in the vehicle. This applies to all variants described in this application (see especially also FIG. 52a).

[0107] The airbag module 12 comprises a module housing 28 in which a folded restraint airbag 30 and a gas generator 32 are accommodated, the gas generator 32 supplying filling gas for inflating the restraint airbag 30.

[0108] The restraint airbag 30 serves for cushioning the occupant 16 in a situation of restraint, and to this end has an inner face 34 directed to the occupant 16 (see e.g., FIG. 3) that comes directly into contact with the occupant 16.

[0109] The airbag module 12 further comprises at least one backup member 36.

[0110] In a normal operating condition, the backup member 36 may be disposed in an initial state in a holder 38 inside the module housing 28 so that it is not visible from an outside of the vehicle seat 10.

[0111] A transfer mechanism 40 realized in this case by a gas supply via the gas generator 32 helps move the backup member 36 out of the holder 38 so that it extends out of the module housing 28 through an exit opening 42 for the restraint airbag 30.

[0112] The transfer mechanism 40 could also be realized by a mechanical drive, e.g., using spring force or an electric motor.

[0113] FIGS. 1 and 3 illustrate the vehicle seat 10 and the airbag module 12 in a situation of restraint, while FIG. 2 shows the airbag module 12 in the initial state during normal driving before the restraint airbag 30 is inflated.

[0114] During normal driving, the backup member 36 is in its initial state inside the module housing 28, whereas in the situation of restraint it adopts a restraining state in which it has exited the module housing 28.

[0115] In the restraining state, the inflated restraint airbag 30 rests with its rear side 45 on an inner face 47 of the backup member 36 facing the contact area 14. Thus, the backup member 36 backs the restraint airbag 30 against an outward movement away from the contact area 14. In this example, the loads produced by the engagement of the occupant 16 are transferred to the vehicle seat 10, more exactly to a rigid seat frame. In so doing, the backup member 36 exerts a force F acting toward the contact area 14 upon the restraint airbag 30, said force F being formed as a counterforce to the load caused by the occupant 16.

[0116] The side of the backup member 36 remote from the vehicle occupant 16 is usually located freely in the vehicle interior and, thus, does not bear against a component affixed to the vehicle.

[0117] In general, the restraint airbag 30 in the restraining state is always located between the occupant 16 and the backup member 36 so that the backup member 36 is not in direct contact with the occupant 16.

[0118] When the airbag module 12 is disposed, as shown, on a vehicle seat 10, the backup member 36 extends primarily in the area of the exit opening 42 from the vehicle seat 10 along the rear side 45 of the restraint airbag 30. The backup member 36 is both narrower and shorter than the restraint airbag 30, as is also evident from FIGS. 7 to 12.

[0119] In this embodiment, the backup member 36 is in the form of a dimensionally stable backup member and, therefore, will be denoted hereinafter with the reference symbol 36a. The dimensionally stable backup member 36a is at least in portions a rigid component.

[0120] A stop 44 on the module-side end of the backup member 36a and on the exit opening-side end of the module housing 28 prevents the backup member 36a from being displaced beyond the restraining state.

[0121] When the dimensionally stable backup member 36a is transferred from its initial state to its restraining state, in the example it is slid, in its entirety, linearly along the holder 38 out of the exit opening 42 by the gas pressure. The walls of the holder 38 act as a guide and predefine an exit direction.

[0122] In FIGS. 4 to 6, a variant of the just described embodiment is shown. In this case, an additional gas generator 46 used to move the backup member 36 is provided in the airbag module 12. In this event, the gas generator 32 serves exclusively for inflating the restraint airbag 30. Instead of a second gas generator 46, also a two-stage gas generator in which one stage is associated with the restraint airbag 30 and the other stage is associated with the backup member 36 (not shown) can be used.

[0123] FIG. 4 illustrates the airbag module 12 in the initial state during normal driving. FIG. 5 illustrates the airbag module 12 during activation, while FIG. 6 shows the airbag module 12 after activation, both of the restraint airbag 30 and the backup member 36 being in the restraining state.

[0124] The additional gas generator 46 can be triggered simultaneously with the gas generator 32, but also time-shifted and few milliseconds before or after the gas generator 32 is activated.

[0125] FIGS. 7 to 12 show different options of arranging plural airbag modules 12 on a vehicle seat 10. FIGS. 7, 9 and 11 show each of the airbag modules 12 before activation, wherein the respective restraint airbags 30 and backup members 36 are in their initial states, while FIGS. 8, 10 and 12 illustrate the airbag modules 12 in the activated state, wherein the respective restraint airbags 30 and backup members 36 are in the restraining state.

[0126] In the variant shown in FIGS. 7 and 8, on each of both sides of the seat 10, more precisely the contact area 14, an airbag module 12 is disposed. One of the airbag modules 12 is located at the backrest 22, while the second airbag module 12 is provided on the opposite side at the headrest 26.

[0127] Hence, the two restraint airbags 30 wrap around the vehicle occupant 16 from opposite sides. In this example, each of the two restraint airbags 30 is shaped transversely to the contact area 14 so that it extends in a curve substantially to the opposite side of the contact area 14 (see FIG. 8).

[0128] The two backup members 36, on the other hand, are significantly shorter and do not reach to an imaginary centerline of the contact area 14 or the seat 10.

[0129] In the variant shown in FIGS. 9 and 10, a total of four airbag modules 12 are arranged on the vehicle seat 10 each of which is provided on both sides of the headrest 26 and of the backrest 22.

[0130] As FIG. 10 illustrates, here the restraint airbags 30 are selected to be shorter transversely to the contact area 14 and only reach to about the center of the contact area 14. The individual restraint airbags 30 are substantially mirror-symmetrical to the centerline of the seat 10 so that the occupant 16 is encompassed from both sides by the restraint airbags 30.

[0131] FIGS. 11 and 12 show a variant in which, as in the latter example, a total of four airbag modules 12 are provided which are disposed on both sides of the headrest 26 and on both sides of the seat base 18.

[0132] In the two latter examples, the restraint airbags 30 of the airbag modules 12 are configured on the seat base 18 or the backrest 22 along the vertical direction of the vehicle seat 10 to have such a length that they offer protection to both the upper legs and the torso of the vehicle occupant 16.

[0133] In FIGS. 13 to 16, a possible variant of a dimensionally stable backup member 36a is shown.

[0134] The dimensionally stable backup member 36a is made from a plastic material or stable foam, for example, and has plural incisions 48 along its inner face 47 so that the entire dimensionally stable backup member 36a can be formed into an arc so that the inner face 47 takes a concavely curved shape.

[0135] On an outer face 50 opposite to the inner face 47, plural pairs of meshing structures 52 that are formed by specifically shaped incisions along the outer face 50 are provided along the longitudinal extension of the dimensionally stable backup member 36a.

[0136] In the initial state, the respective meshing structures 52 of one pair are still spaced apart from each other (see FIG. 14 and FIG. 15 on the left).

[0137] When the dimensionally stable backup member 36a is shifted from the initial state to its restraining state (see arrow direction P in FIG. 13), it is formed into a curved shape by the guide in the holder 38, for example.

[0138] The individual meshing structures 52 of each pair mesh and interlock with each other so that the dimensionally stable backup member 36a maintains its curved shape in the restraining state (see FIGS. 13 and 15 on the right).

[0139] FIGS. 17 to 20 illustrate another embodiment of an airbag module 12 comprising a dimensionally stable backup member 36a.

[0140] In this example, the dimensionally stable backup member 36a takes the shape of a rigid T-shaped strut, with the beam of the T being located at the free end 54 of the dimensionally stable backup member 36a.

[0141] In the initial state, the dimensionally stable backup member 36a is completely located in the holder 38 and is not visible from outboard of the vehicle seat 10 (see FIG. 19).

[0142] When the backup member 36a is transferred to its restraining state, it is pushed out of the holder 38 through the exit opening 42 by a suitable transfer mechanism 40 (see FIGS. 17, 18 and 20).

[0143] In addition to the T-shaped strut, the dimensionally stable backup member 36a further includes a flexible portion 56 that is made from a netting material, for example, and extends along the beam of the T from the free end 54 to plural fixing points 58 at the module housing 28 or at the vehicle seat 10.

[0144] In this example, another flexible portion 60 is provided that is equally attached to the beam of the T and leads to fixing points 58 which are spaced apart from the fixing points 58 of the first flexible portion 56.

[0145] In the initial state, the flexible portions 56, 60 are folded and located in the holder 38.

[0146] In the restraining state, the rigid T-shaped strut ensures the required stability of the dimensionally stable backup member 36a, while the flexible portions 56, 60 increase the area of the backing surface for the restraint airbag 30.

[0147] FIGS. 21 to 23 illustrate another example for a dimensionally stable backup member 36a having a flexible portion 56.

[0148] A fan-shaped framework of rigid struts 62 which are pivotally connected to each other at one end 64 is provided in this case. A flexible portion 56, e.g., made from a netting material, extends between adjacent struts 62.

[0149] In the initial state, the struts 62 and the flexible portions 56 fixed therebetween are folded and jointly arranged in the holder 38 (FIG. 23). When the rigid struts 62 are transferred to the restraining state, they are fan-like extended and the flexible portions 56 provided therebetween are spanned (see FIGS. 21 and 22). The struts 62 and the flexible portions 56 are located outboard of the holder 38 in the restraining state, whereas a rod portion 66 attached to the ends 64 is retained in the holder 38.

[0150] The spanning can be done, for example, by the outermost flexible portions 56 being fastened to fixing points 58 affixed to the vehicle on the edge of the holder 38 so that a tensile force is automatically produced which spans the rigid struts 62 when the dimensionally stable backup member 36a is pushed out of the holder 38.

[0151] In FIGS. 24 to 43, various possible shapes of a backup member 36 are shown. Where necessary, also in this case, one or more flexible portions 56 (not shown) could be added.

[0152] FIG. 44 illustrates another embodiment of a dimensionally stable backup member 36a. The dimensionally stable backup member 36a is shown in the restraining state. The dimensionally stable backup member 36a is made of plural individual rigid sub-elements 68 that are linearly connected to each other and that are accommodated in the holder 38 when compactly telescoped in the initial state (not shown). While they are transferred to the restraining state, the individual sub-elements 68 are displaced relative to each other, with the total length of the dimensionally stable backup member 36a being increased. In this example, the entire dimensionally stable backup member 36a also takes a shape curved toward the contact area 14.

[0153] The individual sub-elements 68 are disk-shaped in this case and are connected to their respective neighbors at opposite edge portions.

[0154] Also, a telescopic arrangement would be conceivable.

[0155] There could also be provided locking elements which are designed similarly to the meshing structures 52 of FIG. 13, for example, to fix the individual sub-elements 68 in position in the restraining state.

[0156] FIG. 45 illustrates another embodiment. In this case, the dimensionally stable backup member 36a includes a plurality of sub-elements 68 connected to form an area. Analogously to the just described embodiment, the dimensionally stable backup member 36a in the initial state and accommodated in the holder 38 when folded and increases its longitudinal extension, when it is transferred to the restraining state.

[0157] For example, a flat material in a specific folding may be used in this case. It is possible to make use of an auxetic material whose rigidity increases transversely to the direction of extension.

[0158] FIGS. 46 to 48 show another embodiment. In this case, the dimensionally stable backup member 36a is formed by a flexible portion 56 provided with a curable or solidifying material. For this purpose, quickly curing epoxy resins or electro-rheological or magneto-rheological liquids are taken into account (each with appropriate curing devices not shown here).

[0159] A flexible portion 56 provided with an appropriate curable or solidifying material (not shown in detail), such as by impregnating with epoxy resin, is wrapped around the portion of the restraint airbag 30 directly adjacent to the exit opening 42.

[0160] As long as the dimensionally stable backup member 36a is accommodated in its holder 38, the material is liquid and the entire dimensionally stable backup member 36a is therefore flexible. While or shortly after reaching the restraining state, the material cures or solidifies so that the flexible portion 56 is stiffened in the restraining state and exerts a backing effect on the restraint airbag 30.

[0161] FIG. 49 illustrates an embodiment in which the backup member 36 is part of the restraint airbag 30. The backup member 36 forms an inflatable portion of the restraint airbag 30 extending against the general exit direction A (see arrow in FIG. 49) and from the exit opening 42 abuts on the vehicle seat 10 outboard on the backrest 22 or the headrest 26, for example. Due to this shaping, the restraint airbag 30 bears against the vehicle seat 10 when an outwardly directed force F acts upon the same.

[0162] FIGS. 50 to 53 illustrate further embodiments. Here, the backup member 36 is realized by a backup airbag 36b, viz. as an inflatable component having a substantially flexible outer cover.

[0163] It would also be imaginable, of course, to provide a curing or solidifying material as afore-described on the outer cover of the backup airbag 36b. This applies, by the way, to all embodiments described in the following.

[0164] FIG. 50 illustrates the concept. Here, in addition to the restraint airbag 30, one single backup airbag 36b is provided, wherein the restraint airbag 30 is located, in the shown situation of restraint, between the vehicle occupant and, thus, the contact area 14 and the backup airbag 36b. The backup airbag 36b is disposed in the area of the exit opening 42 and is adjacent to the outer face of the vehicle seat 10, in particular to the outer face of the backrest 22 or the headrest 26. In this way, the backup airbag 36b exerts a backing effect on the area of the restraint airbag 30 close to the seat and prevents the latter from being pressed outwards when the occupant 16 engages in the restraint airbag 30.

[0165] The backup airbag 36b is filled at a higher internal pressure than the restraint airbag 30 and has a smaller filling volume than the latter.

[0166] Basically, there is a contact region 70 in which the backup airbag 36b and the restraint airbag 30 are directly adjacent to each other.

[0167] FIG. 52a generally illustrates an airbag module 12 in which the backup member 36 is in the form of a backup airbag 36b. The airbag module 12 is structured analogously to the airbag modules shown in FIGS. 2 to 6. One or more backup airbags 36b are accommodated, in the initial state, in the module housing 28 together with the restraint airbag 30. The filling gas for the backup airbag(s) 36b is either supplied by the gas generator 32 that also fills the restraint airbag 30, or a separate gas generator 46 is provided (indicated by broken lines in FIG. 52a). This airbag module 12, too, can be installed at positions in the vehicle other than a vehicle seat.

[0168] In general, even when a backup airbag 36b is used as backup member 36, it is applicable that said backup airbag 36b in the inflated state abuts on the restraint airbag 30 at a position where the shape of the restraint airbag 30 tends to yield to the action of a force in the direction away from the vehicle occupant, and therefore the restraint airbag 30 must be backed. This backing effect is achieved, for example, exclusively by the backup member 36 or a combination of plural backup members 36. Consequently, the necessity of a backing surface affixed to the vehicle in the area of the restraint airbag 30 is dropped.

[0169] As an alternative, FIG. 51 illustrates an embodiment in which the backup airbag 36b additionally bears against a component 72 affixed to the vehicle, such as a wall that delimits the vehicle interior.

[0170] FIGS. 52 and 53 show embodiments in each of which plural backup airbags 36b are arranged in series, wherein adjacent central backup airbags 36b mutually back each other.

[0171] As a rule, the backup airbag(s) 36b equally exit(s) through the exit opening 42 out of the airbag module 12 where it is/they are accommodated in the initial state together with the folded restraint airbag 30.

[0172] Basically, each of the individual backup members 36, 36a, 36b can be transferred from its initial state to its restraining state irrespective of other backup members 36, 36a, 36b. However, it is equally possible to couple backup members 36, 36a, 36b to each other or to the restraint airbag 30 so that said components are jointly moved.

[0173] FIGS. 54 to 67 illustrate further embodiments in which both a dimensionally stable backup member 36a and a backup airbag 36b are provided as backup members 36. In this example, in the restraining state the backup airbag 36b is always interposed between the restraint airbag 30 and the dimensionally stable backup member 36a. FIG. 54 illustrates this concept.

[0174] In the initial state, the restraint airbag 30 and the two backup members 36a, 36b are jointly accommodated in the airbag module 12.

[0175] On principle, all concepts for dimensionally stable backup members 36a and backup airbags 36b described in the entire application can be freely combined in any number with each other and with other types of described backup members 36. The concretely described embodiments are merely examples.

[0176] FIGS. 55 to 57 show an embodiment in which the dimensionally stable backup member 36a rolls up, when it exits the exit opening 42, to the outside, i.e., directed away from the contact area 14. This behavior can be achieved by a suitable material, such as a thin flat material having a specific folding or a different specific structure. What is important is the fact that a pretension toward one side is produced. A known example hereof are snap bracelets.

[0177] FIGS. 58 and 59 show an embodiment in which the dimensionally stable backup member 36a is made from an auxetic material. When the backup member 36a exits the exit opening 42, its thickness is increased perpendicularly to the direction of extension, whereby in turn the backing action is increased.

[0178] FIG. 60 shows an embodiment in which the backup airbag 36b includes plural chambers telescoped into each other which fill when they are transferred to the restraining state. The dimensionally stable backup member 36a may be selected at will.

[0179] FIG. 61 illustrates an embodiment in which the dimensionally stable backup member 36a and the backup airbag 36b are coupled via a gear unit 74. For this purpose, the sides of the backup members 36a, 36b facing the gear unit 74 have appropriate structures in which the gearwheels can engage.

[0180] FIGS. 62 to 64 show embodiments in which the dimensionally stable backup member 36a is pivotally fixed on the vehicle seat 10. In the initial state (in broken lines in the Figures) the dimensionally stable backup member 36a is located in a suitable holder inside the vehicle seat 10 so that it is not visible from outside. For transferring it to the restraining state, it is pivoted about an axis 76 so that its free end 54 comes to lie outboard of the vehicle seat and constitutes a reaction surface to the backup airbag 36b.

[0181] Irrespective of the pivotable arrangement of the dimensionally stable backup member 36a, FIG. 62 illustrates a variant in which each of the backup airbag 36b and the restraint airbag 30 is assigned to a separate gas generator 32, 46 (or a separate stage of a multi-stage gas generator).

[0182] The gas supply to the backup airbag 36b is activated first, before the gas supply to the restraint airbag 30 is activated. As a result, the backup airbag 36b opens a cover (not shown) of the module housing 28 of the airbag module 12.

[0183] The restraint airbag 30 is optionally fastened to the backup airbag 36b and, when the backup airbag 36b is deployed, is also pulled out of the module housing 28.

[0184] This step takes place especially before the gas supply to the restraint airbag 30 is activated.

[0185] In an alternative variant, the backup airbag 36b and the restraint airbag 30 are filled by the same gas generator 32 which to this end has two different outlets.

[0186] The backup airbag 36b is inflated at a higher pressure than the restraint airbag 30 and maintains the higher pressure throughout the entire service life. To achieve this, a membrane that maintains the difference in pressure may be provided, for example.

[0187] FIGS. 65 to 67 illustrate embodiments in which the dimensionally stable backup member 36a is configured as a firm part of the vehicle seat 10, for example as a part of a rigid seat frame. In the initial state, too, the dimensionally stable backup member 36a is visible from outside in these embodiments and is part of the side bolster of the backrest 22 or the headrest 26, for example. In the situation of restraint, the inflated backup airbag 36b bears against the inner face 47 of the dimensionally stable backup member 36a.

[0188] FIG. 67 moreover shows a form fit between the dimensionally stable backup member 36a and the backup airbag 36b that is obtained by a complementary shaping of the surfaces of the backup members 36a, 36b adjacent in the contact region 70 and that additionally improves the backing action to the restraint airbag 30.

[0189] As already described in the foregoing, airbag modules 12 may be provided on both sides of the vehicle seat 10. The restraint airbags 30 are designed so that opposite restraint airbags 30 contact each other in front of the vehicle occupant 16.

[0190] FIG. 68 shows an embodiment in which the backup member 36 is in the form of a backup chamber constituting an inflatable portion of the restraint airbag 30. The restraint airbag 30 is in the form of a multi-chamber airbag, the backup chamber 36c and the restraint chamber 30′ being separated by a partition wall 71.

[0191] In the shown filled state, the backup chamber 36c is filled at a higher internal pressure than the restraint chamber 30′ of the restraint airbag 30. The backup chamber 36c and the restraint chamber may be filled with gas by the same gas generator, wherein the latter may include, e.g., two gas outlets to this end so that in the backup chamber 36c that has a smaller volume than the restraint chamber 30′ a higher internal pressure can be reached.

[0192] Alternatively, the partition wall 71 may comprise overflow openings. Those overflow openings may be particularly closable, wherein the overflow openings are closed, for example, in response to the internal pressure of the backup chamber 36c or the restraint chamber 30′ or in response to deployment of the restraint airbag 30, in particular the restraint chamber 30′, or the backup chamber 36c. For example, overflow openings including closure elements can be used, as they are shown, e.g., in DE 10 2019 101 284.8 using the example of a knee airbag.

[0193] FIGS. 69 to 71 illustrate different times of deployment of the restraint airbag 30 and the backup member 36 between an initial state and a restraining state, wherein in this embodiment the backup member 36 has two leg elements 78 between which plural cross struts 80 connecting the leg elements 78 are arranged. In the restraining state (FIG. 71), the leg elements 78 are arranged in portions substantially V-shaped relative to each other. Between the leg elements 78, plural cross struts 80 are arranged in a rung-like manner, the length of the cross struts 78 being reduced toward the joint tip 86 of the leg elements 78.

[0194] The structure of the backup member 36 has a structure based on the two-ray base element of the bone fish fin, whereby the backup member 36, when force is applied by the restraint airbag 30 in the contact region 70 shown by the arrow 82, does not back away in the direction of force (arrow 82), but the tip 86 of the backup member 36 moves in a direction opposite to the direction of force, as shown by the arrow 84, and thus stabilizes the restraint airbag 30.

[0195] The leg elements 78 may be configured particularly as inflatable elements and/or as resiliently flexible elements and the cross struts 80 may be configured particularly as inflatable elements and/or as dimensionally stable elements.

[0196] For example, the leg elements 78 and/or the cross struts 80 can be manufactured from the same fabric as the restraint airbag and can form plural inflatable chambers, for example. As an alternative, the leg elements 78 and/or the cross struts 80 can be made from suitable plastics, such as polyurethanes, for example. As is evident from FIGS. 69 to 71, in such embodiment the leg elements 78 and the cross struts 80 are preferably connected to each other so that in the initial state (FIG. 69) the backup member 36 can be stowed in a compact manner, e.g., in the module housing 28, and deploys to its final shape which it has in the restraining state (FIG. 71) only when the airbag module 12 has been activated.

[0197] In FIGS. 72 and 73, embodiments are shown in which each of the two restraint airbags 30 located on different sides of the vehicle seat 10 has a fixing structure 80 that detachably fixes the two restraint airbags 30 to each other. In the case of FIG. 68, the fixing structures 80 are formed by magnets, whereas in the case of FIG. 69 a form fit is chosen by the complementary design of the adjacent surfaces of the two restraint airbags 30.