Airbag module and vehicle safety system

Abstract

The invention relates to an airbag module (10) for a vehicle safety system (100), comprising a holding device (24) and an airbag (14) having an airbag wall (18) surrounding an inflatable chamber (16) and a first traction mechanism (31) and a second traction mechanism (32), the pulling mechanism limits the maximum volume of the chamber (16) and / or affects the profile of the airbag. The holding device (24) has a holding position, in which the pulling means (31, 32) are fixed to the holding element (26) and the airbag (14) is inflated in the case of restraint into a first state having a first maximum volume and / or a first airbag profile, and a release position, in which the pulling means (31, 32) are released from the holding element (26). In the release position, the pulling mechanism (31, 32) is released and the airbag (14) is inflated into a second state with a second maximum volume and / or a second airbag profile in the case of restraint. The invention further relates to a vehicle safety system (100) comprising such an airbag module (10).

Description

Technical Field

[0001] The invention relates to an airbag module for a vehicle safety system, the airbag module comprising an airbag and a holding device for a tensioning mechanism. In addition, the invention relates to a vehicle safety system having such an airbag module. Background Art

[0002] Airbags are components of vehicle safety systems. Usually, a tension mechanism is attached to the airbag. The deployment of the airbag can be controlled by means of the tension mechanism, for example by releasing the tension mechanism after the airbag has been at least partially filled with gas. In this way, the desired deployment characteristics of the airbag can be achieved.

[0003] Furthermore, the tensioning mechanism can prevent the airbag from deploying too far in a certain direction when in the inflated state. This function is used, for example, in adaptive airbag concepts or for active airbag venting. In the context of autonomous driving, which is becoming increasingly important, the vehicle occupant can adopt different postures, for example a sitting position when driving himself or a lying position when the vehicle is driving autonomously. If the vehicle occupant is in a lying position, the airbag must deploy significantly further towards the vehicle occupant when necessary than if the vehicle occupant is in a sitting position and is therefore closer to the steering wheel. The tensioning mechanism therefore limits the extent to which the airbag can be deployed towards the driver when the vehicle occupant is in a sitting position. Since the airbag strives to deploy completely, high forces act on the tensioning mechanism in this case. Summary of the invention

[0004] The object of the present invention is to provide an airbag module for a vehicle safety system, the airbag of which can be reliably inflated into different states in a restraint situation.

[0005] This object is achieved by an airbag module for a vehicle safety system, which comprises an airbag and a retaining device. The airbag has an airbag wall surrounding an inflatable chamber and a first tensioning mechanism and a second tensioning mechanism, which limit the maximum volume of the chamber and / or influence the airbag contour. The chamber can have at least two different maximum volumes and / or at least two different airbag contours. The first tensioning mechanism and the second tensioning mechanism each have a fixed end fixed to the airbag wall and a retaining end arranged opposite to the fixed end. The retaining device has a retaining element and is further provided for adjusting the retaining element between a retaining position and a release position. The positions are assigned to different maximum volumes and / or airbag contours, so that the maximum volume and / or airbag contour in the retaining position is different from the maximum volume and / or airbag contour in the release position. In the retaining position, the first tensioning mechanism and the second tensioning mechanism are respectively fixed to the retaining element by means of the retaining ends, and the airbag is inflated to a first state with a first maximum volume and / or a first airbag contour under restraint. In the release position, the first tensioning means and the second tensioning means are each decoupled from the retaining element and the airbag is inflated in the restrained situation to a second state having a second maximum volume and / or a second airbag contour.

[0006] According to the invention, it has been recognized that in this way, in the case of a restraint, i.e. when the airbag module is triggered in an accident and the airbag is thus inflated, the load can be distributed to the two tensioning means, whereby the tensioning means can reliably restrain the airbag wall even when high pressure is present in the chamber. This ensures that the airbag can be reliably inflated into different states in the case of a restraint. Furthermore, the distribution of the load to the two tensioning means makes it possible to use thinner tensioning means or other tensioning means materials. Furthermore, the use of two tensioning means also has the advantage of reliably and stably positioning the airbag.

[0007] In one embodiment, in the holding position, the first tensioning means and the second tensioning means are coupled to the holding element by means of the holding ends in such a way that the tensile forces exerted on the holding element by the holding ends when the airbag is inflated in the restraining situation at least partially compensate for one another. In this way, the loads to which the holding element is subjected in the holding position are reduced, so that the tensioning means are reliably restrained by the holding element.

[0008] The first and second traction means can each have a connecting section which connects the fixing end to the holding end. In the holding position, the connecting section of the first traction means at least partially extends away from the holding element in the opposite direction to the connecting section of the second traction means. In particular, in the holding position, the connecting section of the first traction means extends away from the holding element completely in the opposite direction (i.e. in the top view at an angle of 180°) to the connecting section of the second traction means. This design can minimize the loads acting on the holding element.

[0009] In another embodiment, the holding element is a component that can be changed by the existing pyrotechnic charge under constraint, which releases the pulling mechanism after the charge is ignited. In this way, the holding element can be quickly and reliably adjusted to the release position under constraint.

[0010] It can be provided that the retaining element is a pin-shaped body which can be destroyed by the pyrotechnic charge. This ensures that the tension mechanism is released. In particular, the tension mechanism cannot accidentally remain hooked on the retaining element in this way, because the retaining element is destroyed and therefore no longer exists. Alternatively, the retaining element can also be moved by the pyrotechnic charge in order to release the tension mechanism. It is also conceivable that the retaining element does not release the tension mechanism by pyrotechnic activation, but by other means, for example electromagnetically.

[0011] According to one embodiment, the holding device has a rear side and an opposite front side, which faces the main deployment direction of the airbag. The holding element is arranged on the rear side and extends away from the rear side, in particular opposite to the main deployment direction. This design has the advantage that the tensioning means in the holding position partially extends around the holding device and is thus restrained by the holding device, whereby the loads acting on the holding element can be reduced, in particular when the tensioning means rests against a housing or a similar element (non-holding element) of the holding device.

[0012] According to another embodiment, the holding ends each form a loop. In this case, the holding element extends through the two loops in the holding position, whereby the tensioning mechanism is effectively and reliably fixed on the holding element.

[0013] It can be provided that the holding ends are coupled to one another, in particular are wrapped around one another, in such a way that when the airbag is inflated in the restraint situation, the first and second tensioning means remain connected to one another via the holding ends in the released position. In this way, the second state, into which the airbag is inflated, can be different from a second state in which the two tensioning means are released but not connected to one another.

[0014] Furthermore, when the airbag is inflated in the restrained situation, the mutually connected tensioning means can be fixed or held on the retaining device in the release position. The tensioning means are thus restrained / held by the retaining device both in the retaining position and in the release position. However, the first and second states into which the airbag is inflated are different, since the relative position of the tensioning means to one another is changed due to the removed retaining element and thus the effective length of the two mutually connected tensioning means is increased relative to the retaining position.

[0015] Additionally or alternatively, the first and second traction means may be limiting straps, ie the traction means extend at least partially through the chamber.

[0016] According to the present invention, in order to solve the above-mentioned object, a vehicle safety system is also provided, which includes the airbag module according to the present invention having the above-mentioned advantages and a control unit connected to the holding device in a signal transmission manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Other advantages and features are apparent from the following description and the accompanying drawings. The accompanying drawings are as follows:

[0018] Figure 1 A schematic diagram shows a vehicle safety system according to the invention, comprising an airbag module according to the invention with an airbag in a first inflation state;

[0019] Figure 2 Shown in schematic diagram Figure 1 The vehicle safety system of claim 1, wherein the airbag is in a second inflation state;

[0020] Figure 3 A schematic detail illustration shows a holding device for an airbag module according to the invention according to a further embodiment, the holding element of which is in a holding position; and

[0021] Figure 4 Schematic detail diagram Figure 3 A retaining device in which the retaining element is in a released position. DETAILED DESCRIPTION

[0022] exist Figure 1 2 shows a vehicle safety system 100 for a motor vehicle, which comprises an airbag module 10 and a control unit 12 .

[0023] The airbag module 10 includes an airbag 14 having an inflatable chamber 16 and an airbag wall 18 surrounding the chamber 16 .

[0024] In the present embodiment, the airbag 14 is a front airbag disposed in a steering wheel 20 or steering wheel of the motor vehicle.

[0025] In principle, the airbag 14 can be any airbag and / or can be fixed on any element of the motor vehicle, such as the dashboard or steering column of the motor vehicle. However, the airbag 14 is in particular a front airbag that protects in the event of a frontal collision.

[0026] Furthermore, the vehicle safety system 100 includes an inflator 22 by means of which the airbag 14 can be inflated in a restraint situation in order to provide protection for one or more vehicle occupants.

[0027] In this case, the gas generator 22 is part of the airbag module 10 and is arranged in the chamber 16 , but this is not mandatory.

[0028] In an alternative embodiment, the gas generator 22 may be disposed separately from the airbag module 10 and / or may be disposed at any location in the motor vehicle or in the airbag module 10 .

[0029] In all cases, however, the gas generator 22 is connected to the chamber 16 in such a way that the gas generated by the gas generator 22 in the event of a restraint flows into the chamber 16 in order to inflate the airbag 14 .

[0030] In this context, the airbag 14 is configured to be inflated to a first state (see Figure 1 ) or the second state (see Figure 2 ), in a first state, the chamber 16 has a first maximum volume and the airbag 14 has a first contour, and in a second state, the chamber 16 has a second maximum volume different from the first maximum volume and the airbag 14 has a second contour different from the first contour, in order to provide a protective effect in a restraint situation, which protective effect is especially adapted to the posture of the one or more vehicle occupants in the motor vehicle. The airbag 14 is deployed in a main deployment direction H.

[0031] For this purpose, the airbag module 10 has a holding device 24 , which comprises a holding element 26 which is adjustable between a holding position and a release position, as well as a first tensioning mechanism 31 and a second tensioning mechanism 32 .

[0032] The holding device 24 is fixed to the steering wheel 20 . Specifically, the holding device 24 is usually mounted on a module base or generator support of the airbag module 10 and is fixed to the steering wheel 20 via the airbag module 10 .

[0033] The holding device 24 is controlled here by the control unit 12 , which is connected to the holding device 24 in a signal-transmitting manner and which can also be provided for controlling the gas generator 22 .

[0034] The first tensioning means 31 and the second tensioning means 32 are limiting straps and each have a fixing end 33 , 34 fixing the tensioning means 31 , 32 to the airbag wall 18 , a retaining end 35 , 36 arranged opposite the fixing end 33 , 34 , and a connecting section 37 , 38 connecting the respective fixing end 33 , 34 to the respective retaining end 35 , 36 .

[0035] In this embodiment, the holding ends 35, 36 are respectively configured as rings (see Figure 2 ).

[0036] In one embodiment, the first tensioning means 31 and the second tensioning means 32 are designed identically.

[0037] Furthermore, the holding device 24 has a front side 40 facing the main deployment direction H and an oppositely arranged rear side 42 on which the holding element 26 is arranged.

[0038] In the exemplary embodiment shown, the retaining element 26 is a pin or a pin-shaped body which, in the retaining position, extends counter to the main deployment direction H away from the rear side 42 and passes through the retaining ends 35 , 36 of the tensioning means 31 , 32 which are designed as loops.

[0039] In this way, in the holding position, the tensioning means 31 , 32 are fixed to the holding device 24 via the holding ends 35 , 36 .

[0040] The holding position preferably forms the starting position of the holding device 24 or of the airbag module 10 .

[0041] In order to adjust the holding element 26 from the holding position to the release position (see Figure 2 ), the holding device 24 has a pyrotechnic charge 44 which ignites under restraint and thereby destroys the holding element 26, so that the holding ends 35, 36 are no longer fixed to the holding element 26 and are therefore released. Figure 2 The location where the retaining element 26 was arranged is shown by dashed lines.

[0042] In principle, the holding element 26 can be designed in any desired manner as long as it is ensured that the holding ends 35 , 36 are securely fixed on the holding element 26 in the holding position and are released by the holding element 26 in the release position.

[0043] Additionally or alternatively, the retaining element 26 can be adjusted in any desired manner between the retaining position and the release position.

[0044] In particular, in an alternative embodiment, the retaining element 26 can be adjusted between the retaining position and the release position in a non-destructive manner, for example by displacing or adjusting the retaining element 26 in the main deployment direction H.

[0045] Thus, when the airbag module 10 is triggered in a restraint situation, the airbag 14 may be inflated to a first state (see Figure 1 ), in which the holding element 26 is in the holding position and the tensioning means 31 , 32 are fixed to the holding element 26 via the holding ends 35 , 36 .

[0046] The airbag module 10 is designed in this case such that the tensioning means 31 , 32 are tensioned between the airbag wall 18 and the retaining element 26 and thus limit the contour and the maximum volume of the inflated airbag 14 to a first contour and an associated first maximum volume.

[0047] The connecting section 37 of the tensioned first tensioning means 31 extends away from the holding element 26 in the opposite direction to the connecting section 38 of the tensioned second tensioning means 32, so that the tensile forces in the holding element 26 at least partially compensate each other, which are introduced into the holding element 26 by the tensioning means 31, 32. As a result, the moment load of the holding element 26 at its bearing point is also advantageously reduced.

[0048] Preferably, the connecting sections 37 , 38 extend diametrically opposite to one another at least in one plane, ie at an angle of 180°, so that the respective components of the moments in this plane completely compensate for one another.

[0049] In order to ensure a corresponding extension of the connecting sections 37 , 38 or of the tensioning means 31 , 32 , the holding device 24 has a correspondingly designed guide 46 in which the connecting sections 37 , 38 are guided.

[0050] Additionally or alternatively, the airbag module 10 may have correspondingly designed guides 46 for the connecting sections 37 , 38 on any element of the airbag module 10 .

[0051] Instead of the first state, the airbag 14 may be inflated to the second state (see Figure 2 ), in which the holding element 26 is in the released position and the pulling means 31 , 32 are separated from the holding element 26 and are therefore not fixed to the holding element.

[0052] exist Figure 2 In the embodiment shown, the airbag module 10 is designed in such a way that the tensioning means 31 , 32 are completely separated from the holding device 24 and do not restrict the expansion of the airbag 14 .

[0053] As a result, airbag 14 has a second contour and an associated second maximum volume in the second state.

[0054] In the illustrated embodiment, according to Figure 1The first state of the airbag 14 is distinguished from the second state of the airbag 14 not only by its maximum volume but also by its contour / geometry. However, variant embodiments are also conceivable in which the airbag 14 has an almost constant maximum volume in the first and second states and essentially only differs by its airbag contour and a possibly changing deployment position.

[0055] exist Figure 3 and 4 In an alternative embodiment shown in FIG. 1 , the annular retaining end 35 of the first pulling mechanism 31 extends through the annular retaining end 36 of the second pulling mechanism 32, so that when the retaining element 26 is in the release position, the annular retaining ends 35, 36 remain linked to each other (see Figure 4 ).

[0056] Of course, the pulling mechanisms 31 , 32 can be connected or coupled to one another via the holding ends 35 , 36 in any desired manner as long as it is ensured that the pulling mechanisms 31 , 32 remain connected to one another when the holding element 26 is adjusted into the release position.

[0057] For example, the retaining ends 35 , 36 can be twisted around one another and / or connected to one another via correspondingly designed connecting elements, such as ties.

[0058] The airbag module 10 is designed in this case such that the tensioning means 31 , 32 connected to one another are held fixed to the holding device 24 in the released position of the holding element 26 , whereby the tensioning means 31 , 32 are similar to Figure 1 The embodiment shown in FIG. 1 is stressful and influences the contour / geometry and the maximum volume of the airbag 14 .

[0059] In contrast to the state in which the retaining element 26 is in the retaining position, the effective length of the connected pulling means 31 , 32 , i.e. the length from the fixing end 33 of the first pulling means 31 along the pulling means 31 , 32 to the fixing end 34 of the second pulling means 32 , is extended by approximately the diameter D of the retaining element 26 .

[0060] Therefore, in this embodiment, the second state differs from the first state in that the effective length of the tensioning mechanisms 31 , 32 in the second state is greater than in the first state and the airbag 14 can therefore further expand in the main deployment direction H by approximately half the diameter D.

[0061] This means that, with Figure 1 and 2 Similar to the illustrated embodiment, the airbag 14 has a first maximum volume and a first contour in the first state and a second maximum volume and a second contour in the second state, the second maximum volume and the second contour being different from the first maximum volume and the first contour.

[0062] In this manner, a vehicle safety system 100 and an airbag module 10 are provided that ensure that the airbag 14 is reliably inflated to the first state or the second state when the airbag module 10 is triggered in a restraint situation.

[0063] By providing two tensioning means 31 , 32 , the load acting on the tensioning means 31 , 32 in the tensioned state is reduced, in particular halved.

[0064] Furthermore, the moment acting on the holding element 26 in the holding position is reduced since the two tensioning means 31 , 32 act on the holding element 26 in opposite directions.

[0065] Furthermore, the tensioning means 31, 32 can be deflected in the region of their holding ends 35, 36 at the deflection obstacle, whereby the cable friction at the deflection obstacle is used in a targeted manner in order to further reduce the load on the holding element 26. The total wrap angle of the tensioning means 31, 32 at the respectively associated deflection obstacle can be selected, for example, so that when the airbag 14 is inflated and the holding element 26 is in the holding position, the frictional forces generated between the tensioning means 31, 32 and the deflection obstacle amount to at least 20% of the tensile forces at the holding ends 35, 36 of the tensioning means 31, 32.

[0066] The invention is not limited to the embodiments shown. In particular, individual features of one embodiment can be combined in any desired manner with features of other embodiments (in particular independently of other features of the respective embodiment).

Claims

1. An airbag module (10) for a vehicle safety system (100), the airbag module comprising an airbag (14) and a retaining device (24), in, The airbag (14) has an airbag wall (18) surrounding an inflatable chamber (16) and has a first tensioning mechanism (31) and a second tensioning mechanism (32), which limit the maximum volume of the chamber (16) and / or influence the contour of the airbag (14), the chamber (16) being able to have at least two different maximum volumes and / or the airbag (14) being able to have at least two different contours, The first pulling mechanism (31) and the second pulling mechanism (32) respectively have fixed ends (33, 34) fixed to the airbag wall (18) and retaining ends (35, 36) arranged opposite to the fixed ends (33, 34). The holding device (24) has a holding element (26) and is provided for adjusting the holding element (26) between a holding position and a release position, and the positions are assigned to the different maximum volumes and / or airbag contours, so that the maximum volume and / or airbag contour in the holding position differs from the maximum volume and / or airbag contour in the release position, In the holding position, the first tensioning means (31) and the second tensioning means (32) are fixed to the holding element (26) by means of holding ends (35, 36) respectively and the airbag (14) is inflated to a first state with a first maximum volume and / or a first airbag contour under restraint conditions, and In the release position, the first tensioning means (31) and the second tensioning means (32) are respectively decoupled from the retaining element (26) and the airbag (14) is inflated to a second state with a second maximum volume and / or a second airbag contour under restraint.

2. The airbag module (10) according to claim 1, It is characterized in that In the holding position, the first tensioning means (31) and the second tensioning means (32) are coupled to the holding element (26) by means of the holding ends (35, 36) in such a way that the tensile forces applied to the holding element (26) by the holding ends (35, 36) at least partially compensate for each other when the airbag (14) is inflated in a restrained situation.

3. The airbag module (10) according to claim 2, It is characterized in that The first pulling mechanism (31) and the second pulling mechanism (32) respectively have a connecting section (37, 38) which connects the fixed end (33, 34) to the holding end (35, 36), and in the holding position, the connecting section (37) of the first pulling mechanism (31) at least partially extends away from the holding element (26) in the opposite direction to the connecting section (38) of the second pulling mechanism (32), in particular: in the holding position, the connecting section (37) of the first pulling mechanism (31) completely extends away from the holding element (26) in the opposite direction to the connecting section (38) of the second pulling mechanism (32).

4. Airbag module (10) according to any one of the preceding claims, It is characterized in that The retaining element (26) is a component which can be modified under restraint by an existing pyrotechnic charge (44) and which releases the pulling mechanism (31, 32) after the charge (44) has been ignited.

5. The airbag module (10) according to claim 4, It is characterized in that The retaining element (26) is a pin-shaped body which can be destroyed or displaced by a pyrotechnic charge (44).

6. Airbag module (10) according to any one of the preceding claims, It is characterized in that The retaining device (24) has a rear side (42) and an opposite front side (40), the front side facing the main deployment direction (H) of the airbag (14), the retaining element (26) being arranged on the rear side (42) and extending away from the rear side (42), in particular opposite to the main deployment direction (H).

7. Airbag module (10) according to any one of the preceding claims, It is characterized in that The holding ends (35, 36) each form a loop, through which the holding element (26) extends in the holding position.

8. Airbag module (10) according to any one of the preceding claims, It is characterized in that The retaining ends (35, 36) are coupled to one another, in particular twisted together, so that when the airbag (14) is inflated in a restrained situation, the first and second tensioning means (31, 32) are held connected to one another via the retaining ends (35, 36) in the release position.

9. The airbag module (10) according to claim 8, It is characterized in that When the airbag (14) is inflated in a restraining situation, the mutually connected tensioning means (31, 32) are fixed to the holding device (24) in the release position.

10. Airbag module (10) according to any one of the preceding claims, It is characterized in that The first and second pulling mechanisms (31, 32) are limiting belts.

11. Vehicle safety system (100) comprising an airbag module (10) according to any one of the preceding claims and comprising a control unit (12) which is connected to a holding device (24) in a signal-transmitting manner.

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