WO2023007475A1

WO2023007475A1 - Vehicle seat backrest equipped with an airbag device and vehicle seat comprising such a backrest

Info

Publication number: WO2023007475A1
Application number: PCT/IB2022/059250
Authority: WO
Inventors: David GOETHALS; Jérôme PLANSON; Fabrice Charras; Dominique Acker
Original assignee: Faurecia Sieges D'automobile; Zf Automotive Germany Gmbh
Priority date: 2021-07-29
Filing date: 2022-09-28
Publication date: 2023-02-02
Also published as: CN115675221A; FR3125769B1; FR3125769A1

Abstract

The invention relates to a backrest (16) of a seat of a vehicle (10), which backrest comprises a backrest frame (17) having a post (171), the post (171) preferably being intended to be located near the centre of the vehicle (10), and an airbag device (36). The airbag device (36) comprises an airbag (44) and a strap (56) attached to the airbag (44). The airbag device (36) is attached to the post (171) of the backrest frame (17) at at least one first attachment point (48), by means of an attachment device (50) having a pin (52) passing through the post (171). The strap (56) is attached to the pin (52) of the attachment device (50).

Description

Vehicle seat back provided with an airbag device and vehicle seat comprising such a back

Technical area

This description relates to a vehicle seat back, including motor vehicle. A vehicle seat comprising such a backrest is also described.

Prior technique

In the automotive field, in particular, it is known to provide a seat back with a side airbag device - hereinafter side airbag device. Such a device is conventionally attached to an upright of the backrest frame, in particular to the upright of the backrest frame arranged closest to the center of the motor vehicle. Such a side airbag device thus aims to limit the risk of head-to-head impact of the occupants of two seats arranged transversely one beside the other in the motor vehicle, in particular in the event of a side impact.

[0003] However, the manufacture of such a seat, comprising in particular the placement of padding to be covered with a cover, makes it difficult to access the highest part of the backrest frame, in particular the highest part of the uprights of the backrest frame. In these conditions, the side airbag device is often fixed relatively low on the upright of the backrest frame.

[0004] It appeared that because of this relatively low attachment of the side airbag device, the deployment of the airbag (or airbag) is not completely satisfactory. Indeed, the airbag tends to deploy with a movement having a transverse component, relative to the motor vehicle equipped with the vehicle seat. The air bag then deploys too far inboard of the vehicle, moving away from the normal occupant position in the vehicle seat. As a result, the head of the seat occupant can be moved transversely relatively significantly, before coming into contact with the deployed airbag. Summary

[0005] This description improves the situation.

[0006] To this end, a vehicle seat backrest is described comprising a backrest frame with an upright, the upright preferably being intended to be placed in the vicinity of the center of the vehicle, and an airbag device, the airbag device comprising at least one airbag and a strap attached to the airbag, the airbag device being attached to the post of the backrest frame at at least a first attachment point , by means of a fixing device with a rod passing through the upright, the strap being fixed to the rod of the fixing device.

[0007] Thus, advantageously, the strap makes it possible to force a more vertical deployment of the airbag, without requiring full access to the highest part of the backrest frame in order to install a new attachment point for the device there. airbag on the backrest frame. [0008] According to preferred embodiments, the backrest according to the invention comprises one or more of the following characteristics, taken alone or in combination:

- the upright has a through opening, the strap passing through the through opening; - the first fixing point is placed high up on the upright, below the through opening;

- the strap has a length allowing attachment to the rod, only when the strap passes through the through opening;

- the strap is made of nylon; - the strap has a tensile strength of at least 100 DaN, preferably 150 DaN, more preferably at least 170 DaN, and even more preferably greater than 200 DaN;

- the fixing device comprises a threaded rod and a nut, or a rivet;

- the airbag device comprises an inflation cartridge of the airbag, fixed on the pillar, the inflation cartridge of the airbag security being preferably directly fixed on the pillar, the airbag being preferably further folded into a pocket holding the airbag in position relative to the cartridge;

- the airbag device comprises a housing receiving the airbag and an inflation cartridge for the airbag, the housing being fixed to the upright of the backrest;

- the case forms a chute receiving the strap, the chute passing through the through opening in the upright of the backrest;

- the amount forms a flange on at least a portion of the edge of the through opening;

- a sleeve surrounds the strap, at least at the level of the through opening;

- the strap has an opening through which the rod of the fastening device passes, two washers crimped onto the strap being interposed between the rod of the fastening device and the strap, in the opening of the strap; And

- the airbag device is attached to the upright at at least one second attachment point, the second attachment point being positioned on the upright, such that the first attachment point is located high up on the upright, between the second fixing point and the through opening in the upright.

According to another aspect, there is also described a motor vehicle seat comprising a seat with a seat frame and a backrest as described above in all its combinations, the backrest frame being fixed to the seat frame.

According to yet another aspect, there is described a method for producing a vehicle seat back, in particular a vehicle seat back as described above in all its combinations, comprising the steps consisting to: i) providing at least one backrest frame upright, the upright preferably being intended to be disposed near the center of the vehicle; ii) providing an air bag device, the air bag device comprising at least one air bag and a strap attached to the air bag, iii) attaching the air bag device to the the frame of backrest in at least a first fixing point, by means of a fixing device with a rod passing through the upright, the strap being fixed to the rod of the fixing device.

[0011] The fastening device may comprise a threaded rod and a nut, step iii) consisting in tightening the nut on the threaded rod with a predetermined tightening torque.

Brief description of the drawings

[0012] Other characteristics and advantages will appear during the following description of one of its embodiments, given by way of non-limiting example, with reference to the attached drawings. On the drawings:

[0013] FIG. 1 schematically represents a side view of an example of a vehicle seat;

[0014] FIG. 2 schematically represents in perspective a first example of a backrest frame fitted with a first example of a side airbag device, which can be implemented in the vehicle seat of FIG. 1;

[0015] FIG. 3 schematically represents a detail of the backrest frame equipped with the side airbag device of FIG. 2;

[0016] FIG. 4 schematically represents a sectional view of a detail of the backrest frame equipped with the side airbag device of FIG. 2;

[0017] FIG. 5 schematically represents in perspective a second example of a backrest frame fitted with a second example of a side airbag device, which can be implemented in the vehicle seat of FIG. 1;

[0018] FIG. 6 schematically represents a detail of the backrest frame equipped with the side airbag device of FIG. 5;

[0019] FIG. 7 schematically represents an exploded view of the upright of the backrest frame equipped with the side airbag device of FIG. 5.

Description of embodiments

In the various figures, the same references denote identical or similar elements. For the sake of brevity, only the elements that are useful for the understanding of the described embodiment are shown in the figures and are described in detail below.

[0021] In the following description, when reference is made to qualifiers of absolute position, such as the terms "front", "rear", "top", "bottom", "left", "right", etc., or relative, such as the terms "above", "below", "upper", "lower", etc., or to qualifiers of orientation, such as "horizontal", "vertical", etc., reference is made, unless otherwise specified, to the orientation of the figures or of a vehicle seat in its normal position of use.

[0022] In particular, the longitudinal direction X means the longitudinal direction of the seat. The longitudinal direction of the seat is considered to be the same as the longitudinal direction of the motor vehicle in which the seat is mounted. This longitudinal direction X corresponds to the normal direction of travel of the vehicle. The longitudinal direction X is horizontal. The transverse direction Y of the seat thus corresponds to the transverse or lateral direction of the motor vehicle. This transverse direction corresponds to a direction perpendicular to the normal direction of travel of the vehicle. The transverse direction Y is horizontal. Finally, the vertical direction Z is a vertical direction of the seat, perpendicular to the longitudinal and transverse directions.

[0023] FIG. 1 schematically represents a motor vehicle seat 10 mounted on a slide mechanism 12.

The seat 10 comprises a seat 13, with a seat frame 14 and a seat trim 15, on which a backrest 16, with a backrest frame 17 and a backrest trim 18, is mounted. The backrest frame 17 is here pivotable about a transverse axis A, with respect to the seat frame 14. To do this, a hinge mechanism 20 is arranged between the seat frame 14 and the backrest frame 17.

The seat 13 is mounted on movable sections 22, also called slides or male sections, via feet 24, 26. Each movable section 22 is part of a slide 12 and is associated with a fixed section 28. Profile fixed 28 is also called rail or female section. The fixed profile 28 is fixed to the floor 30 of a motor vehicle.

The seat 10 comprises in this example a manual control element 32, called a lifter, for sliding control of the slides 12. This manual control element 32 makes it possible in particular to lock and unlock the sliding stop systems of the movable profiles 22 with respect to the respective fixed sections 28. Once the stop systems have been unlocked, the manual control element 32 can also be used to cause the movable sections 22 to slide relative to their respective fixed sections 28 of the slide 12 in the longitudinal direction X of the slides 12. The sections fixed 28 and mobile 22 slides 12 are generally metallic.

Alternatively, the movement of the movable sections 22 relative to the fixed sections 28 is controlled by means of an actuator.

According to the example illustrated, the seat 10 may also include a headrest 34. The headrest 34 may also include a headrest frame and a headrest trim.

In the following, examples of backrests 16 that can be implemented in the seat 10 of FIG. 1, facing Figs. 2, Figs. 3 and Figs. 4.

[0030] As illustrated in FIG. 2, the backrest frame 17 essentially comprises a first upright 17i, a second upright 172, a first crosspiece 173, hereinafter referred to as "lower crosspiece 173", and a second crosspiece 174, hereinafter referred to as "high crosspiece 174" . The uprights 17i, 172 and the crosspieces 173, 174 form a back frame 17 in the form of a frame. To do this, the uprights 17i, 172, and the crosspieces 173, 174 can be fixed together, in particular welded together. Alternatively, the back frame 17 is in one piece, the latter being for example molded. The bottom 173 and/or top 174 crosspiece connects the two uprights 17i, 172, each bottom 173 and/or top 174 crosspiece extending mainly in the transverse direction Y of the vehicle seat 10. [0031] For example, the upright 17i and/or the upright 172 is/are a side upright/s/ux. In particular, the first lateral upright 17i may be intended to be arranged most centrally in the motor vehicle, while the second lateral upright 172 may be intended to be arranged on the door side of the vehicle. The first upright 17i is thus intended, according to the example illustrated, to be arranged as close as possible to a longitudinal median plane of the vehicle. In other words again, the first upright 17i is the upright of the backrest frame 17 closest to the neighboring seat, of the same row of seats. The lower crosspiece 173 is intended to be the closest crosspiece to the hinge device 20, the hinge device even being able to be fixed on the lower crosspiece 173. The upper crosspiece 174 is intended to be the closest crosspiece to the headrest 34.

[0032] As illustrated in FIG. 2, a side airbag device - hereinafter side airbag device - 36 is attached to the first upright 17i. The side airbag device 36 shown here is of the "far side" (or "remote side") type in that it is mounted on the first upright 17i of the backrest frame 17, located closest to the center of the motor vehicle.

[0033] Here, the side airbag device 36 comprises a housing 38 with a base 40 and a cover 42 closing the base 40. An airbag 44 (or airbag) and an airbag inflation cartridge 46 44 are housed in housing 38. Cartridge 46 is in fluid communication with airbag 44. Housing 38 is shaped to open upon deployment of airbag 44.

[0034] The housing 38 is fixed to the first upright 17i of the back frame 17.

The housing 38 is fixed to the first upright 17i at a first fixing point 48 by means of a fixing device 50 with rod 52 passing through here the housing 38 and the first upright 17i of the backrest frame 17. Here , the fixing device 50 comprises a threaded rod 52 integral, in particular made in one piece, with the inflation cartridge 46 of the airbag 44. Here, the rod 52 passes through the first upright 17i, and a nut 54 screwed onto a threading of the rod 52. Thus, the housing 38 of the side airbag device 36 and the first upright 17i of the frame of backrest are sandwiched between airbag inflation cartridge 46 44 and nut 54.

Remarkably, here, a strap 56 is also clamped between the cartridge 46, via the housing 38 of the side airbag device 36 and the first upright 17i, and the nut 54, in the vicinity of a first end. longitudinal of the strap 56. Here, strap is called a strip of flexible material. The strip is for example rectangular, such that the length of the strip is much greater than the width of the strip, the width of the strip being itself much greater than the thickness of the strip. Here, the strap 56 has a hole in the vicinity of the first longitudinal end, through which the rod 52 passes. Two washers 58 are here crimped on the strap 56, at the level of the hole passing through the strap 56, in the vicinity of the first end. The two washers 58 are thus interposed between the rod 52 and the strap 56, in the hole. This prevents the threaded rod 52 from damaging the strap 56.

[0037] At its second end, opposite the first end, the strap 56 is attached to the airbag 44. For example, the strap 56 is sewn onto the airbag 44.

Between its two ends, the strap 56 extends through an opening in the housing 38 of the side airbag device 36, not visible in the figures, and an opening 60 passing through the first upright 17i of the frame of backrest 17. Here, the opening 60 passes through the first upright 17i in a transverse direction, relative to the motor vehicle equipped with the vehicle seat 10. Thus, the opening 60 opens onto two inner and outer side faces of the first upright 17i of the back frame 17.

To prevent the strap 56 from being damaged by contact with the edge of the through opening 60, the housing 38 of the side airbag device 36 here forms a chute 62 receiving at least part of the strap 56. The chute 62 is adapted to maintain the strap 56 at a distance from the edge of the through opening 60. To do this, the chute 62 extends here through the opening 60 and, preferably, protrudes from the opening 60, from the side of the first upright 17i of the back frame 17, opposite to that where the airbag 44 is arranged. [0040] Alternatively or additionally, the first upright 17i forms a dropped edge or folded edge over at least a portion of the edge of the through-opening 60, capable of being in contact with the strap 56. Thus, the strap 56 n is not in contact with a sharp edge of the first amount 17i.

The strap 56 is for example nylon. Other materials are however accessible to those skilled in the art which are sufficiently resistant for the application targeted here.

[0042] The strap 56 can be stretched when the side airbag device 36 is fixed on the first upright 17i and the first end of the strap 56 is fixed at the level of the first attachment point 48 of the side airbag device 36 on the first amount 17i. Alternatively, the strap 56 is loose so as to facilitate the manipulation of the strap 56 during the installation of the side airbag device 36 on the first upright 17i. However, it is preferable that the strap 56 is not too loose, in order to be tensioned quickly during the deployment of the airbag 44.

[0043] During deployment of the airbag 44, the strap 56 stretching or being already stretched, the point of contact between the strap 56, on the one hand, and the chute 62 or the edge of the through opening 60, on the other hand, performs the function of an additional attachment point, which is located closer to the top of the backrest frame 17, in particular the upper crosspiece 174 than the first attachment point 48. The deployment of the airbag 44 is thereby better guided, in a substantially vertical direction. The proposed assembly thus improves the deployment of the airbag 44, making it more quickly effective.

[0044] In addition, this assembly does not require full access to the highest part of the backrest frame 17, this access often being limited when the side airbag device 36 is attached to the backrest frame 17 , during manufacture of the vehicle seat 10. Access to pass the strap 56 through the through opening 60 is sufficient. The strap 56 being fixed at a fixing point 48 located lower than the through opening 60, the fixing of the strap can be precisely controlled. In particular, the tightening torque of the nut 58 makes it possible to ensure that the attachment of the strap 56 to the first attachment point 48 is satisfactory. In other words, the opening 60 may already be covered with padding when the side airbag device 36 is in place. It then suffices to pass the strap 56 through the opening 60, under the padding already in place, then to fix this strap at the level of the first attachment point 48, which may not be covered with padding at this stage of the manufacture of the file 16.

[0045] Advantageously, also, the strap 56 can be of a length allowing its attachment to the first attachment point 48 only when the strap 56 passes through the opening 60. Thus, the impossibility of attaching the strap 56 at the level of the first attachment point 48 alerts the fitter of the seat back that the strap 56 has not been passed correctly through the opening 60 in the first amount 17i.

To avoid any risk of tearing of the strap 56 during deployment of the airbag 44, the strap 56 may have a tensile strength of at least 100 daN, preferably at least 150 daN, more preferably at least 170 DaN and even more preferably at least 200 DaN.

According to the example illustrated, the housing 38 is also fixed at a second fixing point 64. Here, the second fixing point 64 is located below the first fixing point 48, along the first upright 17i of the seat frame 17. In other words, the second attachment point 64 is closer to the lower crosspiece 173 than the first attachment point 48. In other words again, the first attachment point 48 is closer to the upper crosspiece 174 than the second attachment point 56. Thus, according to the example illustrated, the first attachment point 48 is arranged along the first upright 17i, between the through opening 60 and the second attachment point 64.

Here, at the second attachment point 64, the housing 38 of the side airbag device 36 is fixed to the first upright 17i by means of a second rod 66, here a second threaded rod 66. The second rod 66 is for example integral, in particular made in one piece, with the inflation cartridge 46 of the airbag 44. The second rod 66 passes through the housing 38 and the first upright 17i of the backrest frame 17. A second nut 68, screwed onto the second threaded rod 66, encloses with the cartridge 46, the housing 38 and the first upright 17i.

[0049] Note that here the cartridge 46 of the side airbag device is directly attached to the first upright 17i of the backrest frame 17, here by means of threaded rods integrated into the cartridge 46.

Finally, as shown, an elastic interlocking relief 70 of the housing 38 is received in a window of the first upright 17i. Here, the window in the first upright 17i is through, arranged between the first and second attachment points 48, 64. The elastic fitting relief 70 here takes the form of a stud having anti-return notches 72 in the vicinity of its free end, which rest on the edge of the window passing through the first upright 17i, once the stud 70 has been inserted into the first upright 17i through the window. This elastic interlocking relief 70 can facilitate the positioning of the box 38 on the first upright 17i and thus facilitate its fixing on the first upright by means of the rods 52, 66 and the nuts 54, 68. The elastic interlocking relief 70 makes it possible, for example, to hold the box 38 in position on the first upright 17i, the time to fix the box 38 by means of the threaded rods 52, 66 and the nuts 54, 68.

[0051] Figs. 5 to 7 illustrate a second example of mounting a side airbag device 36 on the first upright 17i of a backrest frame 17, more particularly suited to the case where the side airbag device 36 has no housing 38. Here again, the side airbag device 36 is of the “farside” type, since it is mounted on the first upright 17i intended to be closest to the center of the motor vehicle.

Indeed, the side airbag device 36 may consist of an airbag 44, an inflation cartridge 46 of the airbag 44, in fluid communication with the airbag 44, and, optionally, a concentrator 47 of the deployment force of the airbag 44. The assembly can be covered in whole or in part, in particular the airbag 44, with a flexible pocket contributing to maintaining the airbag in position 44 on the inflation cartridge 46 before deployment of the airbag 44. The flexible pocket, for textile example, keeps the airbag 44 folded around the cartridge 46, in the absence of housing 38. The flexible bag can be fragile enough to tear in the event of inflation of the airbag 44. The airbag security 44 can be fixed on the back frame 17, in particular on the first upright 17i, in particular near the lower end of the first upright 17i.

The inflation cartridge 46 is here directly attached to the first upright 17i of the back frame 17, by means of the threaded rods 52, 66 and the associated nuts 54, 68. A guide piece 74 can however be interposed between the inflation cartridge 46 and the first upright 17i of the seat frame 17. The guide piece 74 has no fixing function, but facilitates the assembly of the inflation cartridge 46 on the first upright 17i of the backrest frame 17. Thus, the guide piece 74 forms the elastic interlocking relief 70 allowing it to be fixed on the first upright 17i. The guide piece 70 also forms two holes 76 adapted to be placed opposite holes in the first upright 17i, corresponding to the first and second attachment points 48, 64.

In addition, here, to protect the strap 56 and prevent it from deteriorating in contact with the edge of the opening 60 passing through the first upright 17i, a protective sleeve 78 surrounds a portion of the length of the strap 56. The protective sleeve 78 is for example made of thick textile and/or comprises a sewn plastic reinforcement. To prevent the protective sleeve 78 from moving, it can be sewn onto the strap 56.

Each of the files described above can in particular be produced by implementing the method for producing a following file.

[0056] Initially, at least a first upright 17i of the backrest frame 17 is provided. As described above, the first upright 17i is preferably intended to be placed near the center of the vehicle.

[0057] In a second step, an airbag device 36 is provided, with or without a housing 38. The airbag device 36 comprises at least one airbag 44 and a strap 56 attached to the airbag 44. The airbag device 36 may also include an air bag 44 inflation cartridge 46 in fluid communication with the air bag 44. A concentrator 47 of the air bag 44 deployment force may also be provided.

Then, the airbag device 36 is fixed on the first upright 17i of the backrest frame 17 at at least one first fixing point 48, by means of a first fixing device 50 with rod 52 Rod 52 passes through first upright 17i. Advantageously, the strap 56 is of such a length that it allows the insertion of the rod 52 into a suitable hole of the strap 56 only if the strap has actually passed through the opening 60 in the first upright 17i. Thus, although the opening 60 is difficult to see if the backrest upholstery is already in place, in particular on the upper part of the backrest, it is possible to check that the strap 56 is correctly positioned, in particular that the strap actually crosses the opening 60.

The strap 56 is fixed to the rod 52 of the fastening device 50, for example by means of a nut 58 when the rod 52 is threaded. Here, a tightening torque can be applied to the nut 58, which again allows the fitter of the backrest to ensure that the strap 56 is correctly mounted, in particular that the strap 56 is correctly fixed at the level of the first point of fixing 48.

[0060] The airbag device 36 can also be fixed on the first upright 17i of the back frame 17 at a second fixing point 64, for example by means of a second fixing device. The second fixing device comprises for example a second rod 66. The second rod 66 crosses the first upright 17i. In the case where the second rod 66 is threaded, a second nut 54 can be screwed onto the second rod 66.

As described previously, the first and/or the second threaded rod/s 52, 66 can be formed/s by the inflation cartridge 46 of the airbag 44. Alternatively, the first and/or the second threaded rod/s 52, 66 can in particular be formed/s by the casing 38, if necessary, or be attached/s to the cartridge 46 or to the casing 38. The assembly of the airbag device 44 can be facilitated by the implementation of a guide piece 74. This guide piece can be separate from the airbag device 44. Alternatively, the piece of guide may be formed by a part of the airbag device 44, in particular by the housing 38, if applicable. The guide piece 74 may in particular comprise a relief 70 for fixing on the first upright 17i of the backrest frame 17 and openings guiding the fixing rods 52, 66 through the first upright 17i, once the guide piece 74 establishment.

The present invention is not limited to the examples described above. On the contrary, the invention is susceptible of numerous variants accessible to those skilled in the art.

Thus, according to the examples described, the rod fastener 50 comprises a threaded rod 52 and a nut 54, screwed onto the threaded rod 52. In these examples, the threaded rod 52 is integral with the cartridge. inflation 46. Alternatively, the threaded rod may be formed by the housing 38 of the side airbag device 36. Also alternatively, the rod fastening device 50 may comprise a threaded rod 52 attached to the housing 38 or to the air bag cartridge. inflation 46 of the side airbag device 36. In both cases, a nut 54 can cooperate with the threaded rod 52.

According to another variant, the rod fastener 50 comprises, preferably consists of, a rivet. A rivet can also be implemented at the level of the second attachment point 64.

[0066] Also, a protective sleeve 78 as described in the context of the second example, can be implemented in the first example, in addition to or instead of the chute 62 and/or the flange. Likewise, a flanged edge can be made on all or part of the edge of the through opening 60, and a protective sleeve 78 can surround the strap 56, preferably by being sewn to the strap 56.

Claims

[Claim 1] Back (16) of a vehicle seat (10) comprising a back frame (17) with an upright (17i), the upright (17i) preferably being intended to be placed near the center of the vehicle (10 ), and an airbag device (36), the airbag device (36) comprising at least one airbag (44) and a strap (56) attached to the airbag (44) , the airbag device (36) being attached to the upright (17i) of the backrest frame (17) at at least a first attachment point (48), by means of an attachment device (50) with a rod (52) passing through the upright (17i), the strap (56) being fixed to the rod (52) of the fastening device (50).

[Claim 2] A vehicle seat back according to claim 1, wherein the post (17i) has a through opening (60), the strap (56) passing through the through opening (60).

[Claim 3] A vehicle seat back according to claim 2, wherein the first attachment point (48) is disposed high on the post (17i), below the through opening (60).

[Claim 4] A vehicle seat back according to claim 2 or 3, wherein the strap (56) has a length permitting attachment to the post (52), only when the strap (56) passes through the through opening (60). ).

[Claim 5] A vehicle seat back according to any preceding claim, wherein the webbing (56) is nylon.

[Claim 6] A vehicle seat back according to any preceding claim, wherein the strap (56) has a tensile strength of at least 100 DaN, preferably 150 DaN, more preferably at least 170 DaN, and even more preferably greater than 200 DaN.

[Claim 7] A vehicle seat back according to any preceding claim, wherein the securing device (50) comprises a threaded rod (52) and a nut (54), or a rivet.

[Claim 8] A vehicle seat back according to any preceding claim, wherein the airbag device (36) comprises an airbag inflation cartridge (46) (44) secured to the upright (17i), the airbag inflation cartridge (46) preferably being directly attached to the upright (17i), the airbag (44) preferably further being folded into a pocket holding the airbag safety inflatable (44) in position relative to the cartridge (46).

[Claim 9] A vehicle seat back according to any one of claims 1 to 7, wherein the airbag device (36) comprises a housing (38) receiving the airbag (44) and a cartridge (46) inflation of the airbag (44), the housing (38) being fixed on the upright (17i) of the backrest (17).

[Claim 10] A vehicle seat back according to claims 2 and 9, wherein the housing (38) forms a trough (62) receiving the strap (56), the trough (62) passing through the through opening (60) in the amount (17i) of the file (17).

[Claim 11] A vehicle seat back according to any preceding claim in combination with claim 2, wherein the post (17i) forms a flange on at least a portion of the edge of the through opening (60) .

[Claim 12] A vehicle seat back according to any preceding claim in combination with claim 2, wherein a sleeve (78) surrounds the strap (56), at least at the through opening (60) .

[Claim 13] Vehicle seat back according to any one of the preceding claims, in which the strap (56) has an opening through which the rod (52) of the fixing device (50) passes, two washers (58) crimped on the strap (56) being interposed between the rod (52) of the fixing device (50) and the strap (56), in the opening of the strap (56).

[Claim 14] A vehicle seat back according to any preceding claim, wherein the airbag device (36) is attached to the post (17i) at at least a second attachment point (64), the second attachment point (64) being positioned on the upright (17i), such that the first attachment point (48) is located high on the upright (17i), between the second attachment point (64) and the through opening (60) in the amount (17i).

[Claim 15] Motor vehicle seat (10) comprising a seat (14) with a seat frame (15) and a backrest (16) according to any one of the preceding claims, the backrest frame (17) being attached to the seat frame (15).

[Claim 16] A method of making a back (16) of a vehicle seat (10), in particular a vehicle seat back according to any one of claims 1 to 14, comprising the steps of: i ) providing at least one upright (17i) for the backrest frame (17), the upright (17i) preferably being intended to be arranged in the vicinity of the center of the vehicle; ii) providing an airbag device (36), the airbag device (36) comprising at least one airbag (44) and a strap (56) attached to the airbag (44) , iii) attaching the airbag device (36) to the upright (17i) of the backrest frame (17) at at least a first attachment point (48), by means of a device (50) fixing rod (52) passing through the post (17i), the strap (56) being fixed to the rod (52) of the fixing device (50).

[Claim 17] A method according to claim 16, wherein the securing device comprises a threaded rod (52) and a nut (54), the step iii) comprising tightening the nut (54) on the threaded rod (52 ) with a predetermined tightening torque.