FR3100500A1 - VEHICLE SAFETY DEVICE - Google Patents

Abstract

A safety device (24) for a vehicle adapted to be arranged opposite an airbag, comprises a firing channel (26) delimiting an opening (28) for deploying the airbag, a movable flap (36 , 38) between a closed position of the opening (28), in which the shutter (36, 38) covers the opening (28), and an open position, in which the shutter (36, 38) allows deployment of the airbag through the opening (28). The firing channel (26) also has four leaves (40) extending into the firing channel (26). The four leaves (40) are shaped to concentrate the pressure exerted by the deploying airbag, substantially towards a preferential center of pressure on the at least one movable flap (36, 38). Figure for the abstract: Figure 6

Description

SAFETY DEVICE FOR VEHICLE

The present invention relates to vehicle safety devices adapted to face an airbag.

A safety device is already known, adapted to face an airbag, comprising a firing channel with an opening for deploying the airbag. An airbag module comprising a compacted airbag can be attached to the firing channel, at the end of the firing channel, opposite the deployment opening. The deployment opening of the airbag is closed by one or more movable flaps in the absence of impact, the flaps being opened by the deployment of the airbag in the event of an impact.

Application FR2902727A describes an example of such a safety device adapted to face an airbag and arranged within a vehicle dashboard.

However, with such a device, the folding of the airbag in the airbag module is generally carried out in a non-precautionary manner. Thus, the deployment of the cushion results in a pushing force on the movable flap or flaps which may vary from one device to another, with deployment times which may also vary. Such variations can be dangerous. In particular, when the device is inserted into a dashboard, pieces of this dashboard can then break and be thrown into the passenger compartment. Also, the deployment of the airbag may be delayed. It can also happen that the airbag tears.

Summary of the presentation

The object of the present invention is in particular to propose a safety device limiting the risks mentioned above.

To this end, the invention proposes a safety device for a vehicle adapted to be arranged opposite an airbag, comprising:
- a firing channel delimiting a deployment opening of the airbag,
- at least one shutter movable between a closed position of the opening, in which said at least one shutter at least partly covers the opening, and an open position, in which said at least one shutter allows the deployment of the airbag through the opening,
the firing channel also having at least four flaps extending into the firing channel, the at least four flaps being shaped to concentrate the pressure exerted by the deploying airbag, substantially towards a preferential center of pressure of the at least one flap mobile.

Thus, advantageously, the leaves make it possible to direct the airbag towards a preferential center of thrust of the movable flap or flaps, by compensating for the variations in production of the airbag module and the folding of the airbag inside the latter. It is thus possible to optimize the thrust of the airbag on the movable flap or flaps closing the firing channel, at the level of the part of the dashboard or any other interior trim, designed to open under the thrust of the airbag deploying.

According to preferred embodiments, the security device has one or more of the following characteristics, taken alone or in combination:
- the firing channel has four side walls, at least one leaf extending from each of the four side walls;
- Said at least four leaves partly overlap, two by two;
- the at least four vents have come together with the firing channel;
- the at least four leaves are attached to the side wall(s) of the channel;
- the at least four leaves are shaped to deform in contact with the deploying airbag;
- the at least four leaves are shaped to pivot relative to the walls of the firing channel, in contact with the deploying airbag;
- the at least four leaves close off the firing channel section;
- the at least four leaves are distributed over at least two heights in the firing channel;
- the distance between the opening and the at least four leaves is between 5 mm and 70 mm, preferably between 5 mm and 25 mm; And
- the safety device comprises at least two movable flaps, mounted facing each other, the at least two flaps being preferably connected by a strip of material intended to break in the event of deployment of the airbag.

According to another aspect, a security system is proposed comprising:
- a safety device as described above in all its combinations, and
- an interior trim element comprising:
-- a coating, and
-- a rigid support covered by the coating,
wherein the coating at least partially covers the at least one flap of the security device.

According to another aspect, a vehicle dashboard is proposed comprising:
- a safety device as described above in all its combinations,
- an interior trim element forming a board body, the safety device being fixed to the board body, and
- an airbag arranged in a housing, facing the firing channel of the safety device.

According to yet another aspect, there is proposed a method of manufacturing a security device as described above in all its combinations, comprising the production in a substantially flat single piece, of an insert forming the at least four leaves, the folding of the insert and the fixing of the insert in a firing channel.

Other characteristics, details and advantages of the invention will appear on reading the detailed description below, and on analyzing the appended drawings, in which:

is a schematic perspective view of the passenger compartment of a vehicle equipped with a dashboard comprising a safety device;

is a partially cut-away side view of an example of a safety device intended to be fitted to the dashboard of FIG. 1;

is a schematic perspective view of the example of the safety device of FIG. 2;

is a schematic view of an insert intended to be implemented in the safety device of FIGS. 2 and 3;

schematically illustrates a step in a method of manufacturing the safety device of FIGS. 2 to 4;

is a view similar to FIG. 4, of a second example of an insert that can be implemented in the safety device of FIG. 2; And

is a view similar to Figure 4, of a third example of an insert that can be implemented in the safety device of Figure 2.

Description of examples of realization

In the various figures, the same references designate identical elements or identical functions.

Figure 1 schematically shows the passenger compartment of a vehicle 10 equipped with a vehicle interior trim piece.

In this case, the interior trim part is a dashboard 12. However, in variant embodiments, the interior trim part of the vehicle can be a door panel, a roof trim, a seat, a covering of the central part of the steering wheel, or any other type of covering element fitted to the passenger compartment of a vehicle.

The dashboard 12 is here a so-called heat-sheathed board with a dashboard body 14 comprising a rigid support 16, a coating 22 formed of a self-breaking sheet 20 whose back is covered with a layer of laminated foam 18. The foam layer 18 has a relatively small thickness. The sheet 20 and the layer of foam 18 form a coating 22 of the rigid support 16. The sheet 20 is on the side intended to be oriented towards the passenger compartment of the vehicle 10.

The rigid support 16 consists for example of an insert made of a rigid plastic material.

In variant embodiments, the dashboard can be a so-called "injected" dashboard composed of a dashboard body constituting the sole element of the dashboard, or even called "foamed".

A safety device 24 is housed under the board body 14. More specifically, the safety device 24 is arranged between the board body 14 and an airbag (not shown).

As shown, the safety device 24 comprises a firing channel 26 of substantially tubular shape, intended to be placed opposite an airbag module, not shown. The airbag module is separate from the firing channel 26. The airbag module can be attached to the firing channel 26. The airbag module comprises, in a housing, a folded airbag and, preferably, means for inflating the airbag. inflatable and, more preferably, means for triggering the means for inflating the airbag. The firing channel 26 is for example welded by vibration to the body of the dashboard 16. The firing channel 26 thus extends between the airbag module and the dashboard. The firing channel is advantageously rigid.

The firing channel 26 delimits an opening 28 for deployment of the airbag. In a known manner, during the rapid inflation of the airbag following an impact suffered by the vehicle, the airbag deploys through the deployment opening 28 towards the interior of the passenger compartment 10. The deployment opening 28 is surrounded by a flange 29, integral with the firing channel 26, preferably made in one piece with the firing channel 26.

The firing channel 26 here comprises four side walls 30. The side walls 30 are preferably rigid. By "rigid" here is meant that they are at least self-supporting. Preferably, the rigid side walls 30 are not deformed during the deployment of the airbag through the firing channel. The firing channel 26 is thus also rigid. Each side wall 30 comprises an inner surface 32 oriented towards the seat for receiving the airbag, and an outer surface 34 opposite the inner surface 32. The firing channel 26 is for example made of thermoplastic elastomer (or TPE) which has particularly interesting elastic characteristics and reduces the risk of breakage of the shooting channel when it is subjected to significant efforts. However, other materials can be used.

In the example illustrated, at least one side wall 30 has openings 31. The openings 31 can in particular allow the airbag module to be fixed to the firing channel 26, for example by means of hooks. Preferably, two opposite side walls 30 have such openings 31.

The safety device 24 further comprises two flaps 36, 38. The flaps 36, 38 cover at least part of the airbag deployment opening 28. In the absence of shocks, the flaps 36, 38 close the opening 28. When a shock occurs, the airbag deploys, comes into contact with the flaps 36, 38 and causes the opening of the flaps 36, 38 .

As illustrated, the flaps 36, 38 are connected to the firing channel 26 by a hinge connection which allows the pivoting of the flaps 36, 38 relative to the firing channel 26 and limits the projection of the flaps 36, 38 in the passenger compartment. 10. In this case, the flaps 36, 38 are made of the same material as the firing channel 26, for example TPE. However, another material can be envisaged in a variant embodiment.

Each hinge connection is here made by means of a respective hinge 46, 48. The hinges 46, 48 are for example made of elastomeric material. Each hinge 46, 48 is made in a single piece with one of the flaps 36, 38, on the one hand, and with the collar 29 surrounding the deployment opening 28 and/or with a side wall 30 of the firing channel 26, on the other hand.

Alternatively, each hinge connection can be made by a net forming a loop, which net is assembled to a respective flap. In this case, a first net forms a first loop between the first shutter and the collar or a side wall 30 of the firing channel 26 thus producing a hinge with a movable axis between the first shutter and the firing channel. Similarly, the second thread forms a second loop between the second flap and the collar or a side wall 30 of the firing channel 26, thus producing a hinge with a movable axis between the second flap and the firing channel. Preferably, in this case, the first and second flaps are made by overmolding the first and second threads, respectively. Also preferably, the collar is also made by overmolding the first and second threads in this case. Alternatively or additionally, the walls of the firing channel are made by overmolding the first and second threads. The nets can be textile, metal, or any other sufficiently resistant material. The term "net" here refers to any flexible sheet material, for example woven, or even knitted. The nets are for example made of aromatic polyamide (also called “aramid”) which has good mechanical strength. However, other materials may be provided as a replacement and/or in addition. The nets have a thickness of the order of a millimeter.

Furthermore, the flaps 36, 38 are delimited by a line of weakness 50. The line of weakness can be produced by any known means, in particular by milling, by weakening or laser cutting, or by giving a reduced thickness to the flaps 36 , 38 together, at this line of weakness 50, directly to the molding, for example. The flaps 36, 38 are thus kept closed in the absence of impact. However, the rupture of the line of weakness 50 allows the opening of the flaps 36, 38 in the event of deployment of the airbag. According to the embodiment in which a rigid support 16 is arranged, at least in part, opposite the flaps 36,38, the rigid support 16 may also have a line of weakness 52, preferably opposite the line of weakening 50 delimiting the flaps 36.38.

Furthermore, remarkably, four leaves 40 extend into the firing channel 26. The firing channel 26 and the leaves 40 are separate elements. In other words, the leaves 40 do not form part of the firing channel 26 and vice versa. As can be seen in FIG. 4, here the four leaves 40 have a substantially triangular shape, each leaf 40 extending from a respective side wall 30 of the firing channel 26. The leaves 40 are shaped to concentrate the pressure exerted by the airbag being deployed, substantially towards a preferential center of thrust. The preferential center of thrust is for example the center of the opening 28. To do this, here, the free ends of the leaves 40 are arranged substantially at the level of the center of the firing channel 26. Thus, the four leaves 40 substantially close the firing channel 26, prior to airbag deployment. In other words, the four wings 40 "fill" a cross section of the firing channel 26. However, the wings 40 can be shaped to deform upon contact with the airbag deploying in the firing channel 26, to allow the passage of the airbag. Alternatively or additionally, the leaves 40 can pivot relative to a wall 30 of the respective firing channel 26, in contact with the airbag deploying in the firing channel 26, again in order to allow the passage of this airbag. In both cases, however, the presence of the flaps 40 makes it possible to refocus the deploying airbag, towards the center of the opening 28 where the action of the airbag on the flaps 36, 38 is most effective. Thus, the leaves 40 exert a certain resistance during the deployment of the airbag, this in order to ensure their function of deflectors refocusing the airbag towards the center of the opening 28, preferential center of thrust on the movable flaps 36, 38.

It should be noted that here the leaves 40 are not directly connected to each other, in particular by an edge. Here, each leaf 40 is only connected to a wall 35 of an insert 37 fixed inside the firing channel 26. To do this, one or more of the walls 35 of the insert may/may for example have openings 33. The openings 33 of the insert 37 can be placed opposite the openings 31 of the walls 30 of the firing channel 26, to allow the fixing of the insert 37 in the firing channel 26. The fixing can then be carried out by means of hooks.

Alternatively, the leaves 40 may be integral with the firing channel 26. According to another a priori preferred alternative, the leaves 40 are each attached to a respective side wall 30. For example, the leaves 40 are welded, glued, screwed or riveted to the side walls 30 of the firing channel 26.

The leaves 40 can for example be made of polyolefin or another thermoplastic or thermosetting material, injected, laminated and/or calendered then folded. The leaves can for example be made of CURV ^TM material.

The distance L between the opening 28 and the four leaves 40, measured along the longitudinal direction of the firing channel 26, is for example between 5 mm and 70 mm of the length of the firing channel 26, preferably between 5 mm and 25 mm, before airbag deployment.

When the airbag is deployed, it is recentered in contact with the leaves 40, before contacting the flaps 36, 38, in this case substantially at the center of the opening 28. Thus, the effect of the airbag makes it possible to tilt the flaps 36, 38 in the passenger compartment 10 of the vehicle due to the presence of the hinges 46, 48. This tilting of the flaps 36, 38 is here optimized because the cushion strikes the flaps 36, 38 substantially at the center of the opening 28.

The safety device 24 can also be fixed by means of the flange 29 surrounding the deployment opening 28 of the firing channel 26. The fixing of the safety device is then carried out for example by welding, in particular by vibration welding. , or by elastic interlocking, on the board body 14. The collar 29 is for example sandwiched between the coating 22 and the rigid support 16, in particular in the case where an opening is provided in the rigid support 16 for the insertion of the firing channel 26. As a variant, the fixing can be carried out by means of a single transverse wall, without this going all the way around the deployment opening 28. This transverse wall can also be provided at another level of the firing channel 26, in the longitudinal direction of the firing channel 26. This transverse wall is not necessarily arranged at the level of the deployment opening.

As a variant, the safety device 24 can be fixed on a board body 14 of a trim element, an airbag being arranged opposite the safety device. It is thus possible to form a dashboard for a motor vehicle.

Figure 5 illustrates a method of making an insert 37, as shown in Figure 4, intended to be fixed in a firing channel 26 and forming the leaves 40. As illustrated in this figure, the four side walls 35 and the four leaves 40 can be made in one piece, substantially planar. Openings 33 can be provided or made in at least one side wall 35. By then folding this single piece and fixing the side walls 35 and/or the leaves 40, an insert 37 can then be formed very easily. The insert 37 can then be fixed inside a firing channel 26, for example by fixing the side walls 35 of the insert 37 on the side walls 30 of the firing channel 26. The openings 33 in the side walls 35 of the insert 37 may also face openings 31 in side walls 30 of firing channel 26 to allow or at least facilitate this attachment of insert 37 in firing channel 26.

Figure 6 illustrates a variant of the insert 37 of Figure 4, in which the leaves 40 partially overlap or overlap in pairs. In other words, each leaf 40 has a part extending below a neighboring leaf 40 and a part extending above another neighboring leaf 40. The leaves 40 thus have a configuration comparable to that of the leaves of a bud. The partial overlapping of the leaves 40 makes it possible to accentuate the refocusing effect exerted by these leaves 40 on the airbag which deploys.

According to an embodiment not illustrated, the leaves 40 can also be curved, with a concavity oriented substantially towards the bottom of the firing channel 26, when the insert is fixed in the firing channel 26, where the cushion comes from. inflatable when it unfolds. Such a curved shape of the leaves 40 is perceived as particularly advantageous for centering the airbag, the leaves then acting even more analogously to the leaves of a bud in the process of hatching. Same curves, the leaves 40 can partially overlap two by two in order to improve the refocusing effect of the deploying airbag.

Figure 7 illustrates another example of insert 37 with another shape of the leaves 40. In this case, the leaves 40 are substantially rectangular. Each leaf 40 is pivotally mounted with respect to a single wall of the respective firing channel 30. In the example illustrated, before the deployment of the airbag, two leaves 40, which together substantially block the section of the insert 37, are located above two other leaves 40, which together also block the section of the insert 37. The two pairs of vents 40 are however pivotable around perpendicular axes.

The invention is not limited to the examples described, but is on the contrary susceptible to numerous variants accessible to those skilled in the art.

In particular, the shutters closing the deployment opening can be mounted pivoting around a fixed axis.

Also, a single flap completely covering the deployment opening can be provided. A U-shaped strip of material can then be provided around this single flap, with a break initiator, preferably also U-shaped.

Also, the leaves 40 extend, in the examples illustrated in Figures 2, 4 and 6, substantially at the same level in the firing channel 26 (that is to say at the same distance from the opening 28, measured along the longitudinal direction of the firing channel 26). Alternatively, however, the leaves 40 can be arranged at different levels in the firing channel 26. In particular, two leaves 40 can be at a first longitudinal distance from the opening 28, and two other leaves 40 can be at a second longitudinal distance. of the opening 28, the first and second longitudinal distances being different.

In the examples described, the aim is to refocus the pressure exerted by the airbag towards the center of the opening 28. More generally, the flaps can be configured to concentrate the pressure exerted by the airbag deploying, substantially towards a center of preferential thrust on the mobile flap(s). By preferential center of thrust, we mean the point or the zone of the flap which must be impacted by the airbag to optimize the opening of the mobile flap(s). The optimization may consist in particular of an increased speed of opening of the flaps and/or a greater amplitude of the rotation of the flaps. For example, in the case where a single movable flap blocks the opening of the firing channel, the flaps can be shaped to concentrate the pressure exerted by the airbag, substantially at two-thirds of the length of the movable flap, from the hinge connecting the movable shutter to the firing channel, and substantially at the center of the movable shutter, in its width. In this case, the length of the shutter is called the dimension of the shutter measured between the edge of the shutter connected to the firing channel by one or more hinges and the edge of the opposite shutter. The width of the flap is the distance separating the two other opposite edges.

The number of flaps is not limited to two as shown in Figure 4. In particular, the opening 28 can be closed by four flaps 40, each closing substantially a quarter of the area of the opening 28.

Finally, in the examples described, four leaves 40 are implemented each time. However, more than four leaves 40 can also be implemented.

Also, in the examples illustrated, the leaves 40 are formed by an insert fixed inside a firing channel. Alternatively, however, the wings 40 can be fixed directly in the firing channel. According to yet another variant, the leaves 40 can be integral with the firing channel.

Claims (10)

Safety device (24) for a vehicle adapted to be arranged opposite an airbag, comprising:
- a firing channel (26) delimiting an opening (28) for deployment of the airbag,
- at least one movable flap (36, 38) between a closed position of the opening (28), in which said at least one flap (36, 38) at least partially covers the opening (28), and an open position, in which said at least one flap (36, 38) allows the airbag to deploy through the opening (28),
the firing channel (26) also having at least four leaves (40) extending into the firing channel (26), the at least four leaves (40) being shaped to concentrate the pressure exerted by the deploying airbag, substantially towards a preferential center of thrust on the at least one movable flap (36, 38). A safety device according to claim 1, the firing channel (26) having four side walls (30), at least one leaf (40) extending from each of the four side walls (30). Safety device according to Claim 1 or 2, in which the said at least four leaves (40) partially overlap, two by two. Safety device according to any one of Claims 1 to 3, in which the at least four leaves (40) are attached to the side wall(s) (30) of the channel. A safety device according to any preceding claim, wherein the at least four leaves (40) are shaped to pivot relative to the walls (30) of the firing channel (26), in contact with the deploying airbag. Safety device according to any one of the preceding claims, in which the at least four leaves (40) close off the section of the firing channel (26). A security device according to any preceding claim, wherein the distance between the opening (28) and the at least four leaves (40) is between 5mm and 70mm, preferably between 5mm and 25mm. Security system comprising:
- a safety device (24) according to any one of the preceding claims, and
- an interior trim element comprising:
-- a coating (22), and
-- a rigid support (16) covered by the coating (22),
wherein the coating (22) at least partially covers the at least one flap (36, 38) of the security device (24). Dashboard for vehicle comprising:
- a safety device (24) according to any one of claims 1 to 7,
- an interior trim element forming a board body (14), the safety device being fixed to the board body, and
- an airbag arranged in a housing opposite the firing channel (26) of the safety device (24). A method of manufacturing a safety device (24) according to any one of claims 1 to 7, comprising the production in a substantially flat single piece, of an insert (37) forming the at least four leaves (40), folding the insert (37) and securing the insert (37) in a firing channel (26).