Vehicle seat occupant restraint device

Abstract

The invention relates to a restraint device (10) for an occupant (20) of a vehicle seat (30), comprising at least one inflation device (190) and at least two safety airbags (100, 200) which, when inflated by the inflation device, are adapted to deploy on either side of the occupant. According to the invention: - when both safety airbags are inflated, one of the safety airbags forms at least one inflatable tethering element (150) adapted to attach to a complementary tethering element (250) of a second safety airbag, and - the first safety airbag has a rapid inflation channel (140) that connects at least a portion of the inflatable tethering element to the inflation device. Figure for the abstract: Fig. 1

Description

Title of the invention: Vehicle seat occupant restraint device Technical field of the invention

[0001] The present invention relates generally to the safety of vehicle passengers, and in particular to the safety of automobile passengers (cars, buses, trucks, vans...).

[0002] It relates more particularly to a restraint device for an occupant of a vehicle seat, comprising two safety inflatable cushions (better known by the English name "airbags") which are adapted to be housed in the seat and which, when inflated, are adapted to deploy on either side of the occupant until they come into contact with each other.

[0003] It also relates to a seat equipped with such a restraint device. State of the art

[0004] Currently, some airbags are housed in the steering wheel of the vehicle and near the windows, so that they can deploy around the passenger in the event of a collision.

[0005] In the context of the autonomization of motor vehicles, it is necessary to review this arrangement, to take into account, for example, the fact that the driver will no longer necessarily be facing the road, steering wheel in hand, but that he may adopt different attitudes.

[0006] In this perspective, a new category of airbags called "cocoon" airbags has begun to be developed.

[0007] Thus, a seat equipped with an airbag in each of the two sides of its backrest is known from document DE102017131140. These two airbags are designed to inflate in the event of a collision so that they deploy on either side of the seat occupant and then in front of them. Once deployed, the end edges of the two airbags overlap in front of the occupant.

[0008] This document explains that the contact surfaces between the two cushions are then coated with a material having a high coefficient of friction. In this way, when, under the effect of inertia, the occupant comes to rest against these two cushions, the latter remain in contact with each other as much as possible in order to prevent the occupant from passing between them and striking the dashboard of the vehicle.

[0009] Unfortunately, this solution does not offer sufficient reliability since it is not guaranteed that the occupant will never pass between the two cushions.

[0010] This problem is all the more pressing given that, in parallel, a motorization solution Safety belts have been developed. This solution consists, in the event of an accident, of tightening the safety belt before the impact to bring the passenger back to the back of their seat, then allowing a (limited) extension of the safety belt during the impact in order to prevent the belt itself from causing injury to the passenger. This solution tends to increase the problem of the passenger passing between the two cushions when the seat belt is released. Presentation of the invention

[0011] In order to remedy the aforementioned drawback of the prior art, the present invention proposes to provide additional attachment means between the two cushions.

[0012] More specifically, the invention proposes a restraint device for an occupant of a vehicle seat, comprising: - at least one inflation device, and - at least two airbags which, when inflated by the inflation device, are adapted to deploy on either side of the occupant in such a way that one of the airbags forms at least one inflatable attachment element which is adapted to attach to a complementary attachment element of a second airbag, in which the first safety airbag comprises a main chamber and a rapid inflation channel which is separate from the main chamber and which connects at least a part of the inflatable anchoring element to the inflation device.

[0013] Thus, thanks to the invention, the rapid inflation channel allows for an inflation sequence of the different parts of the cushions that differs from that which would occur without this channel. This channel ensures that the attachment elements inflate and position themselves correctly before the rest of the cushions are fully inflated.

[0014] It is therefore possible to provide very reliable fastening elements in that they can have shapes designed to fix the edges of the two cushions together regardless of the passenger's attitude, in order to prevent the latter from passing between the two cushions.

[0015] Other advantageous and non-limiting features of the restraint device according to the invention, taken individually or in all technically possible combinations, are as follows: - the additional attachment element is inflatable; - The second safety airbag comprises a main chamber and a rapid inflation channel that connects at least part of the anchoring element complementary to the inflation device; - the first airbag safety system includes a primary chamber which is directly connected to the inflation device and in which the rapid inflation channel and the main chamber originate; - the main chamber has a volume at least twice that of the primary chamber; - the main chamber has a volume at least twice that of the rapid inflation channel; - the additional attachment element delimits an opening and the inflatable attachment element includes a main tube which is adapted to engage through said opening and which has a protruding lateral face from which extends at least one attachment ridge; - the rapid inflation channel has an end which is located inside the main tube; - each attachment bead delimits a volume which is directly connected to the main chamber; - the rapid inflation channel of the second airbag delimits said opening; - the main tube extending axially along a direction of engagement in said opening, at least two hooking ridges are provided, located at different heights along the direction of engagement; - at least two straps are provided which, when both safety airbags are inflated, surround the safety airbags.

[0016] The invention also proposes a vehicle seat, comprising a seat and a backrest which includes a restraint device as mentioned above.

[0017] Of course, the various features, variants, and embodiments of the invention can be combined with one another in various ways, provided they are not incompatible or mutually exclusive. Detailed description of the invention

[0018] The following description with regard to the attached drawings, given by way of non-limiting examples, will make it clear what the invention consists of and how it can be carried out.

[0019] On the attached drawings:

[0020] [Fig-1] is a top view of a seat equipped with a restraint device conforming to a first embodiment of the invention;

[0021] [Fig.2] is a top view of a seat equipped with a restraint device according to a second embodiment of the invention;

[0022] [Fig.3] is a front view of a seat equipped with a restraint device conforming to a third embodiment of the invention;

[0023] [Fig.4] is a graph illustrating a sequence of inflation of different chambers of a cushion of a restraint device.

[0024] As a preliminary point, it should be noted that identical or similar elements of the different embodiments of the invention shown in the different figures will, as far as possible, be referenced by the same reference signs and will not be described each time.

[0025] Figures 1 to 3 show three embodiments of a seat 30 adapted to be installed in a vehicle and capable of accommodating one occupant (here only one at a time).

[0026] In the examples considered here, it is more precisely a car seat 30 that can accommodate the driver 20 of this car (it could of course be another seat in the car).

[0027] Classically, this seat 30 comprises a seat 32 and a backrest 31 which supports a headrest.

[0028] The backrest 31 has a central support part for the driver's back 20, and two sides located on either side of the driver's torso when the latter is seated in a centered position on the seat 30.

[0029] The seat 30 also includes a seat belt system (not shown). This system is preferably motorized, so that the seat belt strap can be tightened or loosened as needed.

[0030] In the three embodiments shown, the seat 30 is equipped with a driver restraint device 10 20 in case of frontal impact, which is separate from the seat belt system and which is more specifically the subject of the present invention.

[0031] In the remainder of this presentation, we will first describe together the components of this restraint device 10 which are common to these three embodiments, and then we will successively describe the elements differentiating these three embodiments.

[0032] Such a restraint device 10 is designed to restrain the driver and cushion the shock felt by the driver when the car hits an obstacle, particularly in the event of a frontal collision of the car.

[0033] As shown in figures 1 to 3, in all modes, this restraint device 10 includes two safety airbags (more commonly referred to as airbags), hereinafter more simply called airbags 100 and 200.

[0034] Here, the restraint device 10 does not include any more cushions.

[0035] The two cushions 100, 200 are entirely housed in the seat 30 as long as no No shock was felt (that is, as long as they are folded and not inflated). More precisely, they are housed in the backrest 31 of this seat 30. One of these cushions 200, the one on the right, is housed in the right side of the backrest 31, while the other cushion 100, the cushion left, is housed in the left side of file 31.

[0036] These two airbags 100, 200 conventionally each comprise a fabric cover 101, 201 and an inflation device 190 for the fabric cover, adapted to be activated in the event of a frontal impact. This inflation device 190 being well known elsewhere, it will not be described here. It may simply be stated that it comprises two separate gas generators 191, each associated with one of the airbags 100, 200. Alternatively, a single gas generator could be used.

[0037] During inflation, the cushions 100, 200 are shaped to deploy on either side of the driver 20, then to fold down in front of the driver 20 so as to come face to face with each other by their end edges.

[0038] In the following description, these two cushions will be described in the inflated state.

[0039] Each cushion 100, 200 mainly delimits a main chamber 120, 220 of large volume and of shape adapted to folding these cushions on the sides and in front of the driver 20.

[0040] The two airbags 100, 200 each also include at least one attachment element 150, 250. The two attachment elements 150, 250, which belong respectively to the two airbags 100, 200, are adapted to attach to each other and together form a "pair of attachment elements". They prevent the driver 20 from passing between the two airbags during a frontal collision.

[0041] At least one of these attachment elements 150 is inflatable. It is inflatable in such a way that it can come into position relative to the other attachment element 250 before being fully inflated, and then it can then fully inflate so as to lock onto the other attachment element 250, without any means of detaching itself from the latter as long as the cushions 100, 200 remain inflated.

[0042] To allow this relative positioning of the attachment elements 150, 250 before the complete inflation of the main chambers 120, 220, at least one of the two cushions 100, 200 has a rapid inflation channel 140, 240 which connects at least part of the inflatable attachment element 150 to the associated gas generator 191.

[0043] In this case, the two attachment elements 150, 250 are inflatable and the cushions 100, 200 are each equipped with at least one rapid inflation channel 140, 240 of these two attachment means 150, 250.

[0044] The idea here is that the two hooking elements 150, 250 (or a part of each of them) are inflated before the main chambers 120, 220 in order to present shapes which allow their docking and relative hooking when the main chambers 102, 220 inflate and bring the hooking elements 150, 250 closer together.

[0045] These attachment elements 150, 250 are preferably located on the end edges of the cushions 100, 200, that is to say opposite the gas generators 191. It is therefore understood that the rapid inflation channels 140, 240 are of particular importance in allowing the attachment elements 150, 250 to inflate before the main chambers 120, 220. Without these channels, the attachment elements would indeed be the last to be inflated.

[0046] In other words, these channels make it possible to modify the natural inflation sequence of the different parts of the cushions, which sequence generally requires these parts to inflate one after the other, starting from the one closest to the gas generator to the furthest one.

[0047] To illustrate the change in sequence brought about by the rapid inflation channel 140, four successive stages of inflation of a theoretical cushion are shown in [Fig. 4]. In this figure, the cushion has three chambers 181, 182, 183 and a rapid inflation channel 184. It can be seen that the rapid inflation channel 184 allows chamber 183, the one furthest from the gas generator 191, to theoretically inflate at the same rate as chamber 191, the one closest to this generator. Chamber 182, which is located between the other two chambers and is supplied with gas via the first chamber 181, begins to inflate only when the first two chambers are fully inflated.

[0048] The rapid inflation channels 140, 240 can take various forms. For example, they can take the form of rubber tubes housed in the main chambers, or the form of conduits delimited by the fabric covers of the cushions, which will then be sewn accordingly.

[0049] As shown in Figures 1 and 2, it can be foreseen that each inflation device 190 has a two-outlet nozzle, one of which opens into the main chamber 120, 220 and the other into the rapid inflation channel 140, 240.

[0050] However, as shown in [Fig.3], it is preferable that each cushion 100, 200 has a primary chamber 110 into which the gases emitted by the inflation device 190 flow directly and which itself flows directly into the main chamber 120, 220 and into the rapid inflation channel 140, 240, through separate orifices.

[0051] By "directly", it is meant that no room is located between the two communicating volumes.

[0052] The notion of "chamber" here will refer to a volume delimited by the fabric envelope, which is distinguished from other chambers in that it is connected to these other chambers by an area of ​​reduced cross-section (orifice, channel...).

[0053] The primary chamber 110 thus makes it possible to collect all the gases from the gas generator 191 in order to distribute them to the main chamber 120, 220 and the rapid inflation channel 140, 240.

[0054] The outlet ports of the primary chamber 110 preferably have substantially identical cross-sections.

[0055] Thus, due to the difference in volume between the main chamber 120, 220 and the rapid inflation channel 140, 240, the latter inflates completely at least twice as fast as the main chamber 120, 220. As a result, the attachment elements 150, 250 can quickly present the shapes adapted to their docking.

[0056] These attachment elements 150, 250 can be in various forms.

[0057] However, preferably, one of the first of the cushions 100 comprises an element 150 male hook adapted to hook into a 250 female hook element of the other cushion.

[0058] As in the first two embodiments, a single pair of attachment elements 150, 250 may be provided to fix the two cushions 100, 200, but alternatively, several may be provided as is the case in the third embodiment.

[0059] In all three embodiments, the female attachment element 250 has an opening 251 adapted to be passed through by the male attachment element 150.

[0060] In the embodiment shown in [Fig. 1], this female attachment element 250 comprises a thick tubular wall extending from the end edge of the cushion 200 and closed at its free end by a thick front wall pierced by the opening 251. The tubular wall and the front wall are separated between two layers of the fabric cover. The rapid inflation conduit 240 then opens into the space separated between these two layers, here by two distinct branches.

[0061] In the two other embodiments shown in Figures 2 and 3, the female attachment element 250 is in the form of a torus that is fixed to the end edge of the cushion 200 and that defines the opening 251. In these two embodiments, the rapid inflation conduit 240 opens into the torus via a single channel. The attachment of the torus to the rest of the cushion is carried out in such a way that, once the cushion 200 is fully inflated, the torus extends orthogonally to the male attachment element 150.

[0062] The male attachment element 150 has a similar shape in all three embodiments.

[0063] It is thus presented in the form of a finger 151 which is adapted to come and be placed through the aforementioned opening 251.

[0064] This male hooking element 150 has, on the side of its end which has passed through the opening 251, at least one bead 152 which is adapted to deploy so as to prevent the finger 151 from coming out of the opening 251.

[0065] The bulge 152 is intended to swell after the finger 151, or at least after a part of the finger 151.

[0066] For this purpose, the finger 151 is formed of two chambers, one of which inflates before the other (this other chamber inflating jointly with the ridge 152).

[0067] In practice, these two chambers are coaxial. The inner chamber 141 has the shape of a cylindrical tube of revolution which is connected to the end of the rapid inflation channel 140. It may be a chamber with a larger cross-section than the cross-section of this channel, or a chamber with the same cross-section, in which case this chamber only forms the free end of the rapid inflation channel 140.

[0068] The outer chamber 153 also has a shape (at the level of the finger 151) substantially cylindrical of revolution with a larger diameter than that of the inner chamber 141. This shape is of course different at the level of the ridges 152.

[0069] This outer chamber 152 communicates directly with the main chamber 120 of the cushion 100, so that the bulges 152 inflate after the main chamber 120.

[0070] In other words, the inflation sequence of the cushion 100 allows the inner chamber 141 to be inflated first, then the main chamber 120 and finally the outer chamber 153 and its ridges 152.

[0071] In parallel, the inflation sequence of the cushion 200, which begins at the same time as that of the cushion 100, allows the female attachment element 200 to be fully inflated first and then the main chamber 220.

[0072] In this way, the latching elements 150, 250 very quickly assume the appropriate shape, and then the main chambers 120, 220 inflate. During this inflation, the finger 151, which is held taut by the inner chamber 141, passes through the opening 251 of the female latching element 250. Finally, the ridges 251 inflate, locking the two latching elements 150, 250 together.

[0073] In the third embodiment of the invention illustrated in [Fig.3], two pairs of attachment elements identical to those in [Fig.2] are provided, located at different heights.

[0074] Providing several pairs of fastening elements can prove useful for the following reasons.

[0075] The first reason is that, exceptionally, a pair of attachment elements may not deploy as intended, in which case these elements may not attach to each other. Providing several pairs of attachment elements will ensure that at least one of the pairs cooperates correctly.

[0076] The second reason is that car drivers can be of different heights and weights. In particular, their heads can be at varying heights. Providing several pairs of attachment points will ensure that one of these pairs are always located approximately at the height of the driver's head.

[0077] The third reason is that the driver may, at the moment of impact, adopt various postures (hands behind head, hands on knees holding a book, etc.). The multiple means of attachment will ensure good shock absorption for the driver regardless of their posture.

[0078] In practice, two or three pairs of fastening means are preferably provided.

[0079] As Figures 1 and 2 clearly show, to ensure proper deployment of the airbags 100, 200 around the driver 20 and good support of his shoulders during the impact, each airbag 100, 200 is preferably equipped with straps 300, 301. These straps are attached at their ends to the backrest and encircle the airbags 100, 200 from the front.

[0080] The purpose of the straps 300 is to restrain the driver's shoulders during a frontal collision, via the airbags. Thus, during the seatbelt release phase, which aims to limit localized bodily injury to the driver's shoulders (when the force exerted by the driver on this belt exceeds a threshold – currently 400 daN, but potentially lower, typically around 200 daN), a relay occurs in that the restraint force of the seatbelt is progressively transmitted to the assembly of airbags 100, 200, and straps 300. It should be noted here that the present invention thus not only prevents the two airbags from separating but also keeps these straps 300 positioned in front of the driver's shoulders. Consequently, the driver's frontal arrest is achieved first through the driver's shoulders and then through the head.

[0081] The present invention is in no way limited to the embodiments described and represented, but a person skilled in the art will be able to make any variation in accordance with the invention.

[0082] Thus, it would be possible to install several restraint devices 10 such as the one described above, in a single bench seat adapted to accommodate several occupants simultaneously.

[0083] According to another variant of the invention, it could be provided that the female attachment element is not inflatable but that it naturally has a shape enabling it to cooperate with the male attachment element.

[0084] According to another embodiment of the invention not shown in the figures, the male attachment element could be provided to have several ridges 152 distributed along the length of the finger 151. In other words, as the finger extends lengthwise from the main chamber to the other cushion, at least two distinct ridges 152 are distributed along the finger. In this embodiment, the attachment elements will be adapted to hook onto each other in a variable position depending on the size and build of the driver. Indeed, if the driver is of small build, the ridge The 152 closest to the base of the finger 151 will be the one that will attach to the female attachment element 250. Conversely, if the conductor is of large build, it will be the ridge 152 closest to the free end of the finger 151 that will attach to the female attachment element 250.

Claims

Demands

1. A restraint device (10) for an occupant (20) of a vehicle seat (30), comprising at least one inflation device (190) and at least two safety airbags (100, 200) which, when inflated by the inflation device (190), are adapted to deploy on either side of the occupant such that a first of the safety airbags (100) forms at least one inflatable tethering element (150) which is adapted to attach to a supplementary tethering element (250) of a second of the safety airbags (200), characterized in that the first safety airbag (100) has a main chamber (120) and a rapid inflation channel (140) which is separate from the main chamber (120) and which connects at least a portion of the inflatable tethering element (150) to the restraint device. inflation (190).

2. Restraint device (10) according to the preceding claim, wherein the additional attachment element (250) is inflatable and wherein the second safety airbag (200) comprises a main chamber (220) and a rapid inflation channel (240) which connects at least a portion of the additional attachment element (250) to the inflation device (190).

3. Restraint device (10) according to any one of the preceding claims, wherein the first safety airbag (100) comprises a primary chamber (110) which is directly connected to the inflation device (190) and in which the rapid inflation channel (140) and the main chamber (120) originate.

4. Retaining device (10) according to the preceding claim, wherein the main chamber (120) has a volume at least twice that of the primary chamber (110) and that of the rapid inflation channel (140).

5. Retention device (10) according to the preceding claim, wherein the additional hooking element (250) delimits an opening (251) and the inflatable hooking element (150) comprises a main tube (151) which is adapted to engage through said opening (251) and which has a projecting lateral face from which extends at least one hooking bead (152).

6. Retaining device (10) according to the preceding claim, in which the rapid inflation channel (140) has an end (141) which is located inside the main tube (151).

7. Retaining device (10) according to the preceding claim, wherein each hooking bead (152) delimits a volume which is directly connected to the main chamber (102).

8. Restraint device (10) according to any one of the three preceding claims, wherein the rapid inflation channel (240) of the second safety airbag (200) delimits said opening (251).

9. Retaining device (10) according to any one of the four preceding claims, wherein, the main tube (151) extending axially along an engagement direction in said opening (251), at least two hooking ridges (152) are provided, located at different heights along the engagement direction.

10. Restraint device (10) according to any one of the preceding claims, wherein there are provided at least two straps (300) which, when the two safety airbags (100, 200) are inflated, surround the safety airbags (100, 200).

11. Vehicle seat (30), comprising a seat (32) and a backrest (31), characterized in that the backrest (31) comprises a restraint device (10) conforming to one of the preceding claims.

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