FR3122623A1 - Vehicle security system - Google Patents

Abstract

A vehicle safety device (11) includes a guide portion (12) for guiding deployment of an air bag (26), a flap (36) adapted to move between a closed position of a opening of the guide part (12), and an opening position and an articulation (38). The articulation (38) connects the flap (36) to the guide part (12). The joint (38) comprises three joint tongues (1; 2; 3) each formed by a flexible net. Each hinge tongue (1; 2; 3) comprises a free portion (501; 502; 503). The length (Ll1) of the free portion (501) of a first hinge tongue (1), located between the other two (2; 3), is greater than the length (Ll2; Ll3) of the free portion ( 502; 503) of these two other hinge tabs (2; 3). Abstract Figure: Figure 2

Description

Vehicle security system

The present disclosure relates to the field of airbag safety systems, in particular for vehicle interiors. Such a system is conventionally used in a motor vehicle to improve the safety of the occupants.

Usually, a vehicle includes at least one safety system intended to protect the users of the vehicle in the event of an accident. The security system is for example part of a dashboard of the vehicle.

The safety system includes a safety device and an airbag module attached to the safety device. The airbag module includes a folded airbag and an airbag inflator. The safety device includes a guide portion for guiding deployment of the airbag during inflation. The guide part comprises an opening through which the airbag is intended to deploy in a passenger compartment of the vehicle, to protect the occupants.

Generally, the opening of the guide part is covered by a plastic flap. The flap can be overmoulded by a support or form a part fixed to the support. The support is generally a dashboard or part of the dashboard. The carrier may include, for example, one hatch portion (usually referred to as a "U" configuration) or two hatch portions (usually referred to as an "H" configuration, "I" configuration). The hatch portion is configured to open upon deployment of the airbag, in the event of a crash, a weakening line or the like surrounding the flap to allow for breakage of the support around the hatch portion to release the hatch.

The deployment of the airbag also causes the rotation of this hatch around a hinge pin.

Despite efforts to make this rupture straightforward, elements can be thrown into the passenger compartment of the vehicle and cause damage to its occupants. In addition, the movement of the hatch part must be controlled to prevent the hatch from colliding with the rest of the wall that has remained in place or the windscreen creating debris that could also be thrown into the passenger compartment of the vehicle.

Summary

This disclosure aims to improve the situation.

To this end, a security device for a vehicle is described, comprising:
- a guide part for guiding the deployment of an airbag in a direction of deployment, the guide part comprising a frame delimiting an opening through which the airbag is intended to deploy,
- at least one flap adapted to move between a closed position, in which the at least one flap at least partially covers the opening, and an open position, in which the at least one flap at least partially releases the opening, to allow deployment of the airbag through the opening, and
- at least one articulation, each articulation connecting a flap to the frame of the guide part, in a direction of articulation, each articulation comprising at least three articulation tongues each formed by a flexible net, each articulation tongue comprising a first portion fixed to the guide part, a second portion fixed to said flap, and a third portion, free, between the first and second portions, a first hinge tongue being located between a second and a third hinge tongue in the hinge direction, the length of the free portion of the first hinge tongue being greater than the length of the free portion of the second hinge tongue and the length of the free portion of the third hinge tongue .

Thus, advantageously, it is possible to better control the kinematics of the opening of the flaps of the safety device, so as to limit or even avoid the drawbacks of known airbag safety devices.

According to preferred embodiments, the security device comprises one or more of the following characteristics, taken alone or in combination:
- each net is made of aramid or polyester;
- the length of the free portion of the second hinge tongue is equal to the length of the free portion of the third hinge tongue;
- the second and third hinge tongues are spaced from the first hinge tongue at the level of the guide part, in the direction of deployment of the airbag;
- the second and third hinge tongues are below the first hinge tongue, at the level of the guide part, in the direction of deployment of the airbag;
- the guide part forms a channel;
- the guide part forms a collar around the opening, the hinge tabs being preferably fixed to the collar;
- the opening comprises a length and a width, the direction of articulation corresponding to the orientation of the length of the opening;
- the second and third hinge tongues are shaped to break before the first hinge tongue, in the event of deployment of the airbag;
- the thickness and/or the width of the second and third hinge tongues is less than the thickness and/or the width, respectively, of the first hinge tongue;
- the second and third hinge tabs have an incipient fracture;
- the three hinge tongues are integral, the three hinge tongues being connected together by a strip fixed to the guide part and/or by a strip fixed to said flap;
- the three hinge tongues are distinct and separated;
- the safety device comprises two movable flaps, each movable flap being fixed to the guide part by a respective hinge, each hinge comprising three hinge tongues each formed by a flexible net, each hinge tongue comprising a first fixed portion to the guide part, a second portion fixed to at least one flap, and a third portion, free, between the first and second portions, a first articulation tongue of each articulation being located between a second and a third tongues of articulation of said articulation, in the articulation direction, the length of the third portion of the first articulation tongue being greater than the length of the third portion of the second articulation tongue and the length of the third portion of the third hinge tongue.

According to another aspect, there is also described a safety system for a vehicle, in particular for a motor vehicle, comprising a safety device as described above, in all its combinations, and an airbag module comprising at least one airbag and airbag inflator means, wherein the airbag module is attached to the guide portion of the safety device such that the guide portion guides the airbag in the event of inflation, up to at least one flap.

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:

schematically shows in section an example of a security system including a first security device;

schematically represents a top view of part of the first safety device of the ;

schematically shows in section a first detail of the articulation of a flap of the first safety device;

schematically shows in section a second detail of the articulation of a flap of the first safety device;

schematically illustrates a first variant of the joint illustrated in ;

schematically illustrates a second variant of the joint illustrated in ;

schematically illustrates a first example of the configuration of an articulation in the safety device of the ;

schematically illustrates a second example of the configuration of an articulation in the safety device of the ; and

schematically illustrates a third example of configuration of an articulation in the safety device of the .

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

Reference is now made to the , represented in a three-dimensional frame (X,Y,Z), comprising a transverse axisX ,a longitudinal axisY and a substantially vertical axisZ. In practice, the axisZis inclined with respect to the vertical direction. The represents an example of a system10security airbag (or "airbag"), seen in section in a planeXZ. Such a security system10is, in known manner, used in a motor vehicle to improve the safety of the occupants. More particularly, such a security system10is for example provided in a dashboard of the vehicle, in order to protect the passenger of the vehicle in the event of an impact.

The safety system 10 essentially comprises a safety device 11 and an airbag module 24 attached to the safety device 11 .

The safety device 11 firstly comprises a body forming a guide portion 12 for an expanding airbag. The guide part 12 comprises, here consists of a tubular portion 14 , preferably substantially cylindrical, forming a firing channel 16 , and a flange 18 in the vicinity of a first end 20 of the firing channel 16 , forming a frame around an opening 22 at the first end 20 of the firing channel 16 . Here, the guide part 12 is in one piece, the tubular part 14 and the collar 18 being integral. The tubular part 14 and therefore the firing channel 16 extend in a main direction Z.

The tubular part 14 of the guide part 12 here comprises four walls 19 . The four walls 19 are parallel in pairs. The walls 19 are preferably rigid. In particular, the walls 19 are self-supporting.

The guide part 12 is for example made of thermoplastic elastomer (TPE) material.

The guide part 12 , in particular the tubular portion 14 of the guide part 12, is adapted to receive the airbag module 24 . The airbag module 24 comprises an airbag 26 , arranged, in particular folded, in a housing 28 , the airbag 24 not being inflated. The airbag module 24 may further comprise a means 30 for inflating the airbag 24 , in particular an inflation cartridge 31 . Alternatively, the airbag 24 of the airbag module 24 is in fluid communication with such an inflation means 30 , in particular such an inflation cartridge 31 , which is located outside the airbag module of security 24 . The housing 28 of the airbag module 24 is here fixed to the firing channel, in particular by means of hooks 32 received in openings 34 of a wall of the cylindrical portion 14 of the guide part 12 , forming the channel shooting 16 . The airbag module 24 is thus attached to a second end 17 of the firing channel 16, opposite the first end 20 .

The airbag module 24 may also include means for triggering the inflation means 30 of the airbag 24 .

The airbag module 24 is disposed in the firing channel 16 such that the airbag 24 deploys in the firing channel 16 and passes through the opening 22 at the first end 20 of the firing channel. shooting 16 when the security system 1 0 is activated.

Furthermore, the safety device 11 here comprises two flaps 36 , which are fixed to the guide part 12 , each by means of a respective hinge 38 .

In this case, the flaps 36 are made of the same material as the guide part 12 , for example TPE. However, another material can be envisaged in a variant embodiment.

The guide part 12 and the flaps 36 are fixed to a support wall 40 , for example by welding. In particular, the guide part 12 is fixed to the support wall 40 by the collar 18 extending around the opening 22 at the first end 20 of the firing channel 16 .

The support wall 40 is for example formed by a dashboard, more precisely the cover of a motor vehicle dashboard. The support wall 40 may be covered with a coating forming an external surface visible to a vehicle occupant. A layer of foam can be interposed between the support wall 40 and the covering.

The support wall 40 has, as illustrated, three weakenings 42 , 44 forming initiators of rupture of the support wall 40 . Two weakenings 42 are arranged substantially in line with a respective hinge 38 , in the direction of extension Z of the firing channel 16 . A third weakening 44 is arranged between the two flaps 36 in the extension direction Z of the firing channel 16 . The support 44 thus forms hatch portions between the weakenings 42 , 44 .

In the absence of shocks on the motor vehicle equipped with the security system 11 , the flaps 36 are in the closed position as illustrated in , in which the flaps 36 at least partially cover the deployment opening 22 of the airbag 26 , at the first end 20 of the firing channel 16 . When an impact occurs, the airbag 26 deploying, comes into contact with the flaps 36 and causes the opening of the flaps 36 , each flap 36 being moved along the connection formed by the respective joint 38 .

In the following, an articulation 38 is described in more detail, it being understood that the two articulations 38 can be identical or symmetrical with respect to a median plane YZ of the safety device 10 .

As is particularly visible on the , each joint 38 comprises, here consists of, three hinge tabs 1 , 2 , 3 . In the present disclosure, the identical or similar elements of the three tongues 1 , 2 , 3 bear the same reference sign, followed by an index corresponding to the reference of the hinge tongue 1 , 2 , 3 . Each joint 38 extends along a joint direction A , here substantially parallel to the longitudinal direction Y. Advantageously, the direction of articulation A corresponds to the direction of extension of one side of the flap 36 associated with the articulation 38 considered. Preferably, the direction of articulation A corresponds to the direction of extension of one of the two largest sides, more preferably of the largest side, of the flap 36 associated with the joint 38 considered. In other words, the direction of articulation A advantageously corresponds to the direction in which the length of the associated flap 36 is measured.

The hinge tabs 1 , 2 , 3 are arranged at a distance from each other, in the direction of articulation A. Here, a first hinge tongue 1 is arranged between, in particular equidistant between, second and third hinge tongues 2 , 3 . In the example shown, the second and third hinge tongue 2 , 3 are identical.

Each hinge tongue 1 , 2 , 3 extends mainly in a direction perpendicular to the hinge direction A. Here, each hinge tongue 1 , 2 , 3 has the shape of a rectangular strip of net. The net is for example made of aramid (or aromatic polyamide) or polyester. Each hinge tongue has a length L1 , L2 , L3 and a width l1 , l2 , l3 . Here, the width l1 of the first tongue 1 is greater than the width l2 , l3 , of the second and third hinge tongues 2 , 3 . The length L1 , L2 , L3 of the three hinge tongues 1 , 2 , 3 is for example equal. The length L1 , L2 , L3 of each hinge tongue 1 , 2 , 3 is measured in a direction substantially perpendicular to the hinge direction A. The width l1 , l2 , l3 of each hinge tongue 1 , 2 , 3 is measured parallel to the hinge direction A.

However, as is more clearly visible on the and , each hinge tongue 1 , 2 , 3 comprises a first portion 4 6 ₁ , 4 6 ₂ , 4 6 ₃ fixed to the guide part 12 , a second portion 4 8 ₁ , 4 8 ₂ , 4 8 ₃ , fixed to the associated flap 36 , and a third portion 50 ₁ , 50 ₂ , 50 ₃ , between the first portion 4 6 ₁ , 4 6 ₂ , 4 6 ₃ and the second portion 4 8 ₁ , 4 8 ₂ , 4 8 ₃ respectively, extending freely between the guide part 12 and the associated flap 36 . In particular, the first portion 4 6 ₁ , 4 6 ₂ , 4 6 ₃ can be molded over by the guide part 12 , in particular by the flange 18 . The _second portion 481 , 482 , ₄₈₃ can be molded over by the associated flap 36 _.

The length L l ₁ , called hereinafter free length, of the third portion 50 ₁ of the first hinge tongue 1 is greater than the length Ll ₂ of the third portion 50 ₂ of the second tongue 2 and the length L l ₃ of the third portion 50 ₃ of the third tongue 3 . The free length L1 ₂ of the second hinge tongue 2 is here equal to the free length L1 ₃ of the third hinge tongue 3 . Advantageously, the free length L1 ₂ , L1 ₃ of the second and third hinge tongues 2 , 3 is less than half the free length L11 of the first hinge tongue 1 . The free length L11 , L12 , L13 of each hinge tongue 1 , 2 , 3 is measured in a plane normal to the hinge direction A.

When the safety system 10 is activated, the airbag 26 deploys substantially along the direction Z of extension of the firing channel 26 . The walls 19 surrounding the firing channel 16 then guide the deployment of the airbag 26 in the direction Z of extension of the firing channel 16 . The guide part 12 , in particular its tubular part 14 thus forms a guide part of the airbag 26 .

The airbag26then comes into contact with the shutters3 6, close to the attenuation44in the support wall40. The airbag26pushing on the shutters36causes the support wall to break40, at the level of the weakenings42,44, shutters36undergoing a displacement essentially in the directionZextension of the firing channel16 to begin with.

The movement in direction Z of the flaps 36 then tends to stretch the free portions 50 ₂ , 50 ₃ of the second and third hinge tongues 2 , 3 , shorter than the free portion 50 ₁ of the first hinge tongues 1 .

Once the free portions 50 ₂ , 50 ₃ of the second and third hinge tongues 2 , 3 have been stretched, the thrust of the airbag 26 on the flaps 36 causes the flaps 36 to pivot essentially about an axis parallel to the transverse direction Y .

Advantageously, the second and third hinge tongues 2 , 3 of each hinge 38 are shaped to break during the movement of the flaps 36 , in particular before the first hinge tongue 1 , the latter preferably being shaped so as not to break. . There are many means for the second and third hinge tongues 2 , 3 to break, in particular before the first hinge tongue 1 , which are known to those skilled in the art. Here, by way of example, the width l2 , l3 and/or the thickness of the threads of the second and third tongues 2 , 3 of each articulation 38 are chosen so that they break. To do so, for example, the width l2 , l3 of the second and third hinge tongues 2 , 3 is significantly less, in particular three times lower, than the width l1 of the first hinge tongue 1 .

Alternatively or additionally, the second and third hinge tabs 2 , 3 may have an incipient break.

It should be noted that the breakage of the second and third hinge tabs 2 , 3 also makes it possible to absorb energy from the flaps 36 , which are thereby slowed down. This limits the risk of projections in the passenger compartment of the motor vehicle.

Once the second and third hinge tabs 2 , 3 are broken, the thrust of the airbag 26 on the flaps 36 induces, initially, a movement of each flap 36 in the direction of extension Z of the channel shooting 16 . The flaps 36 however continue a rotational movement around a transverse axis, by inertia.

When the thread forming the first hinge tongue 1 is in turn stretched, the movement of each flap 36 essentially corresponds to a rotation around a respective transverse axis, controlled by the first hinge tongue 1 . Here, advantageously, the first hinge tongue 1 is shaped to retain its integrity in the event of actuation of the safety system 10 . Thus, this first hinge tongue 1 is not intended to break, in order to maintain the associated flap 36 , fixed to the guide part 12 . This avoids a projection of the flap 36 which could be very dangerous for an occupant of the motor vehicle located in the vicinity of the safety device 11 .

The implementation of a first hinge tongue 1 that is longer than the second and third hinge tongues 2 , 3 makes it possible in particular to completely clear the opening 22 at the first end 20 of the firing channel 16 . Thus, the deployment of the airbag 26 is promoted. In particular, the risk of tearing the airbag 26 is limited. However, the second and third hinge tongues 2 , 3 , which are shorter, make it possible to cause the associated flap 36 to pivot, earlier than the first hinge tongue 1 , during the deployment of the airbag 26 .

The illustrates a variant of the articulation 38 described above. According to this variant, the joint 38 is formed of three joint tongues 1 , 2 , 3 made in one piece. Thus, the three hinge tongues 1 , 2 , 3 are here connected together by a strip 52 of net, at the level of the first portion 46 ₁ , 46 ₂ , 46 ₃ of the hinge tongues 1 , 2 , 3 , overmolded by the flange 18 of the guide part 12 . This makes it easier to handle the three hinge tabs 1 , 2 , 3 at the time of manufacture of the safety device 11 . This can also contribute to a better relative positioning of the three hinge tabs 1 , 2 , 3 relative to each other.

In this case, the articulation 38 can in particular be made from a piece of rectangular net, in which cutouts are made in order to delimit the three articulation tabs 1 , 2 , 3 . In this case, the total length of the three hinge tongues L ₁ , L ₂ , L ₃ can be equal. Consequently, the ends of the second portions 48 ₁ , 48 ₂ , 48 ₃ of the three hinge tongues 1 , 2 , 3 are not aligned parallel to the hinge direction A .

The kinematics of the opening of the flaps 36 in the event of deployment of the airbag 26 remains substantially identical, however.

The illustrates a second variant of the joint 38 , in which the joint 38 is also formed of three hinge tongues 1 , 2 , 3 made in one piece. Here, however, the three hinge tongues 1 , 2 , 3 are connected together by a strip 54 of net, at the level of the second portion 48 ₁ , 48 ₂ , 48 ₃ of the hinge tongues 1 , 2 , 3 , overmolded by the associated flap 36 . This makes it easier to handle the three hinge tongues 1 , 2 , 3 at the time of manufacture of the safety device. This can also contribute to a better relative positioning of the three hinge tabs 1 , 2 , 3 relative to each other.

In this case also, the articulation 38 can in particular be made from a piece of rectangular net, in which cutouts are made in order to delimit the three articulation tabs 1 , 2 , 3 . In this case, the total length L ₁ , L ₂ , L ₃ of the three hinge tongues 1 , 2 , 3 can be equal. Consequently, the ends of the first portions 46 ₁ , 46 ₂ , 46 ₃ of the three hinge tabs 1 , 2 , 3 are not aligned parallel to the hinge direction A .

The illustrates a joint38as previously described, molded over by the guide part12so that the first portions46 ₁ ,46 ₂ ,46 ₃ of the three hinge tabs1,2,3are arranged at the same height, along the directionZextension of the firing channel16, substantially corresponding to the direction airbag deployment26 .

Joint 38 of the is also such that the second portions 48 ₁ , 48 ₂ , 48 ₃ of the three hinge tabs 1 , 2 , 3 are arranged at the same height, along the direction Z of extension of the firing channel 16 .

Alternatively, however, as shown in , the first portions 46 ₂ , 46 ₃ of the second and third hinge tongues 2 , 3 can be arranged above the first portion 46 ₁ of the first hinge tongue 1 , in the direction Z of extension of the channel shooting 16 .

Similarly, the second portions ₄₈₂ , 483 of the second and third hinge tongues 2 _, 3 can be arranged above the second portion 481 of the first hinge tongue 1 _, in the direction Z extension of the firing channel 16 , as shown in .

The illustrates yet another variant, in which the first portions 46 ₂ , 46 ₃ of the second and third hinge tongues 2 , 3 are arranged below the first portion 46 ₁ of the first hinge tongue 1 , in the direction Firing Channel Extension Z 16 .

The also illustrates that the second portions ₄₈₂ , 483 of the second and third hinge tongues 2 _, 3 can be arranged below the second portion 481 of the first hinge tongue 1 _, in the direction Z extension of the firing channel 16 .

The different configurations of , and can also be combined.

These different configurations make it possible to configure a desired height of the flap 36 , from which the second and third hinge tongues 2 , 3 are stretched, independently of the total length of the net forming these second and third hinge tongues 2 , 3 and/or taking into account a given free length L12 , L13 of the desired second and third hinge tongues 2 , 3 . It is thus possible, for example, to obtain the same height of flap 36 when the second and third hinge tongues 2 , 3 are stretched, either by having a greater free length L12 , L13 , or by arranging the second and third hinge tongues 2 , 3 above, in the direction Z of extension of the firing channel 16 .

Of course, the invention is in no way limited to the embodiments described by way of non-limiting illustration.

For example, the guide part of the safety device and the collar can be made in several separate parts, which are assembled together. The guide part of the safety device can itself be produced in several parts assembled together.

In addition, the net can be attached to other places of the guide part, in particular to one of the walls delimiting the shooting channel, rather than to the collar.

Claims (10)

Security device (11) for a vehicle, comprising:
- a guide part (12) for guiding the deployment of an airbag (26) in a direction of deployment (Z), the guide part (12) comprising a frame (18) delimiting an opening (22) by which the airbag (26) is intended to deploy,
- at least one flap (36) adapted to move between a closed position, in which the at least one flap (36) at least partially covers the opening (22), and an open position, in which the at least at least one flap (36) at least partially releases the opening (22), to allow deployment of the airbag (26) through the opening (22), and
- at least one articulation (38), each articulation (38) connecting a flap (36) to the frame (18) of the guide part (12), in an articulation direction (A), each articulation (38) comprising at least three hinge tongues (1; 2; 3) each formed by a flexible net, each hinge tongue (1; 2; 3) comprising a first portion (46 ₁ ; 46 ₂ ; 46 ₃ ) fixed to the guide part (12), a second portion (48 ₁ ; 48 ₂ ; 48 ₃ ) fixed to said flap (36), and a third portion (50 ₁ ; 50 ₂ ; 50 ₃ ), free, between the first (46 ₁ ; 46 ₂ ; 46 ₃ ) and second (48 ₁ ; 48 ₂ ; 48 ₃ ) portions, a first hinge tongue (1) being located between a second (2) and a third (3) hinge tongues in the direction of articulation (A), the length (Ll ₁ ) of the free portion (50 ₁ ) of the first hinge tongue (1) being greater than the length (Ll ₂ ; Ll ₃ ) of the free portion ( 50 ₂ ) of the second hinge tongue tion (2) and the length (Ll ₃ ) of the free portion (50 ₃ ) of the third hinge tongue (3). A security device according to claim 1, wherein each net is aramid or polyester. Safety device according to claim 1 or 2, in which the length (LL ₂ ) of the free portion (50 ₂ ) of the second hinge tongue (2) is equal to the length (Ll ₃ ) of the free portion ( 50 ₃ ) of the third hinge tongue (3). Safety device according to one of Claims 1 to 3, in which the second and third hinge tongues (2; 3) are spaced apart from the first hinge tongue (1) at the level of the guide part (12) , in the direction (Z) of deployment of the airbag (26). Safety device according to any one of the preceding claims, in which the guide part (12) forms a collar (18) around the opening (22), the hinge tongues (1; 2; 3) being of preferably attached to the collar (18). Safety device according to any one of the preceding claims, in which the second and third hinge tongues (2; 3) are shaped to break before the first hinge tongue (1), in the event of deployment of the airbag security (26). A safety device according to claim 6, wherein the thickness and/or the width of the second and third hinge tongues (2; 3) is less than the thickness and/or the width, respectively, of the first tongue joint (1). Safety device according to Claim 6 or 7, in which the second and third hinge tongues (2; 3) have an incipient break. Safety device according to any one of the preceding claims, in which the three hinge tongues (1; 2; 3) are made in one piece, the three hinge tongues (1; 2; 3) being connected together by a band (52) fixed to the guide part (12) and/or by a band (54) fixed to said flap (36). Safety device according to any one of Claims 1 to 8, in which the three hinge tongues (1; 2; 3) are distinct and separate.