WO2024165155A1

WO2024165155A1 - Device for retaining an occupant of a vehicle seat

Info

Publication number: WO2024165155A1
Application number: PCT/EP2023/053183
Authority: WO
Inventors: Jean-Baptiste ROY; Philippe Souville
Original assignee: Renault S.A.S; Nissan Motor Co., Ltd.
Priority date: 2023-02-09
Filing date: 2023-02-09
Publication date: 2024-08-15

Abstract

The invention relates to a device (10) for retaining an occupant (20) of a vehicle seat (30), comprising at least one inflation device (190) and at least two airbags (100, 200) which, when they are inflated by the inflation device, are suitable for deploying on either side of the occupant. According to the invention: - when the two airbags are inflated, a first one of the airbags forms at least one inflatable hooking element (150) which is suitable for hooking onto a complementary hooking element (250) of a second one of the airbags; and - the first airbag includes a fast inflation channel (140) which connects at least one portion of the inflatable hooking element to the inflation device.

Description

DEVICE FOR RESTRAINING AN OCCUPANT OF A VEHICLE SEAT

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to the safety of vehicle passengers, and in particular automobile passengers (cars, coaches, trucks, vans, etc.).

It relates more particularly to a device for restraining an occupant of a vehicle seat, comprising two 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.

It also concerns a seat equipped with such a restraint device.

STATE OF THE ART

Currently, some airbags are housed in the vehicle's steering wheel and near the windows, so that they can deploy around the passenger in the event of an impact.

In the context of the autonomy 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, with the steering wheel in his hands, but will be able to adopt different attitudes.

With this in mind, a new category of airbags called "cocoons" has begun to be developed.

Thus, document DE102017131140 discloses in particular a seat equipped, in each of the two sides of its backrest, with an inflatable cushion. These two cushions are designed to inflate in the event of an impact such that they deploy on either side of the occupant of the seat and then in front of him. Once deployed, the end edges of the two cushions come to overlap in front of the occupant.

In this document, it is explained 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 bear against these two cushions, the latter remain as much as possible in contact with each other in order to prevent the occupant from passing between them and hitting the dashboard of the vehicle.

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

This problem is all the more pressing since, in parallel, a solution for motorizing seat belts has been developed. This solution consists, in the event of an accident, of tightening the seat belt before the impact to bring the passenger back to the bottom of his seat. seat, and then to allow a (limited) lengthening of the seat belt during the impact in order to prevent the belt itself from causing injuries 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

In order to overcome the aforementioned drawback of the state of the art, the present invention proposes to provide additional attachment means between the two cushions.

More particularly, the invention provides a device for restraining 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 such that a first of the airbags forms at least one inflatable attachment element which is adapted to attach to a complementary attachment element of a second of the airbags, wherein the first airbag comprises a main chamber and a rapid inflation channel which is distinct from the main chamber and which connects at least part of the inflatable attachment element to the inflation device.

Thus, thanks to the invention, the rapid inflation channel makes it possible to carry out an inflation sequence of the different parts of the cushions which is different from that which would occur without this channel. This channel then makes it possible to ensure that the attachment elements inflate and position themselves correctly, before the rest of the cushions are fully inflated.

It is thus possible to provide very reliable attachment elements in the sense that they can have shapes designed to fix the edges of the two cushions together whatever the passenger's attitude, in order to prevent the latter from passing between the two cushions.

Other advantageous and non-limiting characteristics of the retaining device according to the invention, taken individually or in all technically possible combinations, are as follows:

- the additional attachment element is inflatable;

- the second airbag comprises a main chamber and a rapid inflation channel which connects at least part of the complementary attachment element to the inflation device;

- the first airbag has a primary chamber which is directly connected to the inflation device and in which the quick inflation channel and main chamber;

- 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 complementary attachment element delimits an opening and the inflatable attachment element comprises a main tube which is adapted to engage through said opening and which has a projecting lateral face from which at least one attachment bead extends;

- the rapid inflation channel has one 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 safety airbag delimits said opening;

- the main tube extending axially in a direction of engagement in said opening, at least two attachment beads are provided located at different heights along the direction of engagement;

- at least two straps are provided which, when both airbags are inflated, surround the airbags.

The invention also provides a vehicle seat, comprising a seat and a backrest which comprises a retaining device as mentioned above.

Of course, the various features, variants and embodiments of the invention may be combined with each other in various combinations to the extent that they are not incompatible or mutually exclusive.

DETAILED DESCRIPTION OF THE INVENTION

The description which follows with reference to the attached drawings, given as non-limiting examples, will make it clear what the invention consists of and how it can be implemented.

On the attached drawings:

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

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

[Fig. 3] is a front view of a seat equipped with a restraint device according to a third embodiment of the invention; [Fig. 4] is a graph illustrating a sequence of inflation of different chambers of a cushion of a restraint device.

As a preliminary point, it will 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.

Figures 1 to 3 show three embodiments of a seat 30 suitable for installation in a vehicle and capable of accommodating an occupant (here only one at a time).

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

Typically, this seat 30 has a seat 32 and a backrest 31 which supports a headrest.

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

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 released as needed.

In the three embodiments shown, the seat 30 is equipped with a device 10 for restraining the driver 20 in the event of a frontal impact, which is distinct from the seat belt system and which is more specifically the subject of the present invention.

In the remainder of this presentation, we will first jointly describe the components of this retaining device 10 which are common to these three embodiments, then we will successively describe the elements differentiating these three embodiments.

Such a restraint device 10 is designed to restrain the driver and absorb the shock felt by the driver when the car hits an obstacle, in particular in the event of a frontal impact of the car.

As shown in FIGS. 1 to 3, in all modes, this restraint device 10 comprises two safety inflatable cushions (more commonly referred to as airbags), hereinafter simply called cushions 100 and 200.

Here, the retaining device 10 does not further comprise cushions.

The two cushions 100, 200 are fully housed in the seat 30 as long as no shock has been felt (i.e. as long as they are folded and not inflated). They are more precisely housed in the backrest 31 of this seat 30. One of these cushions 200, the right one, is housed in the right side of the backrest 31 when the other cushion 100, the left cushion, is housed in the left side of the backrest 31. These two cushions 100, 200 each have a fabric cover as standard.

101, 201 and an inflation device 190 of the fabric envelope, 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 can simply be specified that it comprises here two separate gas generators 191 each associated with one of the cushions 100, 200. Alternatively, a single gas generator could be used.

When inflated, the cushions 100, 200 are shaped to deploy on either side of the conductor 20, then to fold down in front of the conductor 20 so as to come face to face with each other at their end edges.

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

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

The two cushions 100, 200 each further comprise at least one attachment element 150, 250. The two attachment elements 150, 250 which belong respectively to the two cushions 100, 200 are adapted to attach to each other and together form a “pair of attachment elements”. They make it possible to prevent the driver 20, in the event of a frontal impact, from being able to pass between the two cushions.

At least one of these attachment elements 150 is inflatable. It is inflatable such that it can be placed in position relative to the other attachment element 250 before being fully inflated, and then it can be fully inflated so as to lock onto the other attachment element 250, with no means of detaching itself from the latter as long as the cushions 100, 200 remain inflated.

To enable 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 comprises a rapid inflation channel 140, 240 which connects at least part of the inflatable attachment element 150 to the associated gas generator 191.

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.

The idea here is that the two attachment elements 150, 250 (or a part of each of them) are inflated before the main chambers 120, 220 in order to have shapes which allow their docking and their relative attachment when the main chambers

102, 220 inflate and bring the attachment elements 150, 250 closer together.

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 then understood that the rapid inflation channels 140, 240 are of particular importance for allow the attachment elements 150, 250 to inflate before the main chambers 120, 220. Without these channels, the attachment elements would in fact be the last to be inflated.

In other words, these channels allow to modify the natural inflation sequence of the different parts of the cushions, which sequence generally means that these parts inflate one after the other, starting from the one closest to the gas generator to the one furthest away.

To illustrate the change in sequence brought about by the rapid inflation channel 140, FIG. 4 shows four successive steps of inflation of a theoretical cushion. In this figure, the cushion comprises three chambers 181, 182, 183 and a rapid inflation channel 184. It can be seen that the rapid inflation channel 184 makes it possible for the chamber 183, the one furthest from the gas generator 191, to theoretically inflate at the same speed as the chamber 191 closest to this generator. The chamber 182 which is located between the two other chambers and which is supplied with gas via the first chamber 181, begins to inflate only when the first two chambers are fully inflated.

The rapid inflation channels 140, 240 may take various forms. For example, they may take the form of rubber hoses housed in the main chambers, or they may take the form of conduits defined by the fabric covers of the cushions, which will then be sewn accordingly.

As shown in Figures 1 and 2, it can be expected that each inflation device

190 has a nozzle with two outlets, one of which opens into the main chamber 120, 220 and the other which opens into the rapid inflation channel 140, 240.

However, as shown in FIG. 3, it will be preferred that each cushion 100, 200 comprises 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, via separate orifices. By “directly”, it is meant that no chamber is located between the two volumes which communicate.

The concept of "chamber" will here refer to a volume delimited by the fabric envelope, which is distinguished from the other chambers in the sense that it is connected to these other chambers by a reduced section area (orifice, channel, etc.).

The primary chamber 110 thus makes it possible to collect all the gases coming from the gas generator.

191 in order to distribute them towards the main chamber 120, 220 and the rapid inflation channel 140, 240.

The outlet orifices of the primary chamber 110 preferably have substantially identical sections. 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 quickly as the main chamber 120, 220. As a result, the attachment elements 150, 250 can quickly have the shapes adapted to their docking.

These attachment elements 150, 250 can take various forms.

However, preferably, the first one of the cushions 100 comprises a male attachment element 150 adapted to be attached to a female attachment element 250 of the other cushion. 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 as a variant, several may be provided as is the case in the third embodiment.

In all three embodiments, the female attachment element 250 has an opening 251 suitable for the male attachment element 150 to pass through.

In the embodiment shown in FIG. 1 , this female attachment element 250 comprises a thick tubular wall which rises from the end edge of the cushion 200 and which is closed at its free end by a thick front wall pierced by the opening 251 . The tubular wall and the front wall are delimited between two sheets of the fabric envelope. The rapid inflation conduit 240 then opens into the space delimited between these two sheets, here by two separate branches.

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

The male attachment element 150 has a similar shape in the three embodiments.

It thus appears in the form of a finger 151 which is adapted to be placed through the aforementioned opening 251.

This male attachment element 150 comprises, 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.

The bead 152 is intended to inflate after the finger 151, or at least after a portion of the finger 151.

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

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 inflation channel rapid 140. This may be a chamber with a larger section than the section of this channel, or a chamber with the same section, in which case this chamber only forms the free end of the rapid inflation channel 140.

The outer chamber 153 also has a shape (at the finger 151) which is substantially cylindrical in revolution and has a larger diameter than that of the inner chamber 141. This shape is of course different at the level of the beads 152.

This outer chamber 152 communicates directly with the main chamber 120 of the cushion 100, so that the beads 152 inflate after the main chamber 120.

In other words, the inflation sequence of the cushion 100 makes it possible to inflate first the inner chamber 141, then the main chamber 120 and finally the outer chamber 153 and its beads 152.

In parallel, the inflation sequence of the cushion 200, which begins at the same time as that of the cushion 100, makes it possible to fully inflate first the female attachment element 200 and then the main chamber 220.

In this way, the attachment elements 150, 250 very quickly take on an adequate shape, then the main chambers 120, 220 inflate. During this inflation, the finger 151 which is stretched thanks to the inner chamber 141 passes through the opening 251 of the female attachment element 250. Finally, the beads 251 inflate which locks the two attachment elements 150, 250 with each other.

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

Providing several pairs of hanging elements can be useful for the following reasons.

The first reason is that it may happen, exceptionally, that a pair of attachment elements does not deploy as expected, 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.

The second reason is that drivers of the car may be of different heights and weights. In particular, their heads may be at different heights. Providing several pairs of attachment elements will ensure that one of these pairs is always approximately at the height of the driver's head.

The third reason is that the driver may, at the time of the impact, adopt different attitudes (hands behind the head, hands on the knees to hold a book, etc.). The plurality of means of attachment will ensure good cushioning for the driver whatever his attitude.

In practice, two or three pairs of attachment means will preferably be provided. As clearly shown in Figures 1 and 2, to ensure good deployment of the cushions 100, 200 around the driver 20 and good support of his shoulders during the impact, each cushion 100, 200 is preferably equipped with straps 300, 301. These straps are fixed by their ends to the backrest and surround the cushions 100, 200 from the front.

The straps 300 are intended to ensure the retention of the driver's shoulders during a frontal impact, via the cushions. Thus, during the seat belt release phase which aims to limit bodily injury localized on the driver's shoulders (when the force exerted by the driver on this belt passes beyond a threshold - currently 400 daN but may be lower, typically of the order of 200 daN), a relay occurs in the sense that the restraining force of the seat belt is gradually transmitted to the assembly "cushions 100, 200 and straps 300". It should be noted here that the present invention then makes it possible not only to prevent the two cushions from moving apart but also to keep these straps 300 in front of the driver's shoulders. From then on, the frontal stopping of the driver occurs via the two shoulders of the driver then via the head.

The present invention is in no way limited to the embodiments described and shown, but those skilled in the art will be able to provide any variant in accordance with the invention. Thus, it would be possible to install several restraint devices 10 such as that described above, in a single bench seat adapted to accommodate several occupants simultaneously.

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 allowing it to cooperate with the male attachment element.

According to another variant of the invention not shown in the figures, it could be provided that the male attachment element comprises several beads 152 distributed along the length of the finger 151. In other words, the finger extending in length from the main chamber to the other cushion, at least two separate beads 152 are distributed along the finger. In this variant, the attachment elements will be adapted to attach to each other in a variable position depending on the build and morphology of the driver. Indeed, if the driver is of small build, the bead 152 closest to the base of the finger 151 will be the one that will attach to the female attachment element 250. On the contrary, if the driver is of large build, it will be the bead 152 closest to the free end of the finger 151 which will attach to the female attachment element 250.

Claims

[Claim 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 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 airbags (100) forms at least one inflatable attachment element (150) which is adapted to attach to a complementary attachment element (250) of a second of the airbags (200), characterized in that the first airbag (100) comprises a main chamber (120) and a rapid inflation channel (140) which is distinct from the main chamber (120) and which connects at least part of the inflatable attachment element (150) to the inflation device (190).

[Claim 2] A restraint device (10) according to the preceding claim, wherein the complementary attachment element (250) is inflatable and wherein the second airbag (200) comprises a main chamber (220) and a rapid inflation channel (240) which connects at least part of the complementary attachment element (250) to the inflation device (190).

[Claim 3] A restraint device (10) according to any preceding claim, wherein the first 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.

[Claim 4] A 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).

[Claim 5] A retaining device (10) according to the preceding claim, in which the complementary attachment element (250) delimits an opening (251) and the inflatable attachment 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 at least one attachment bead (152) extends.

[Claim 6] A retaining device (10) according to the preceding claim, wherein the rapid inflation channel (140) has an end (141) which is located inside the main tube (151).

[Claim 7] A retaining device (10) according to the preceding claim, wherein each attachment bead (152) delimits a volume which is directly connected to the main chamber (102).

[Claim 8] Restraint device (10) according to one of the three preceding claims, in which the rapid inflation channel (240) of the second airbag (200) delimits said opening (251).

[Claim 9] Retaining device (10) according to one of the four preceding claims, in which, the main tube (151) extending axially in a direction of engagement in said opening (251), at least two attachment beads (152) are provided located at different heights along the direction of engagement.

[Claim 10] A restraint device (10) according to any preceding claim, wherein at least two straps (300) are provided which, when both airbags (100, 200) are inflated, surround the airbags (100, 200).

[Claim 11] Seat (30) for a vehicle, comprising a seat (32) and a backrest (31), characterized in that the backrest (31) comprises a retaining device (10) according to one of the preceding claims.