Airbag module and vehicle steering unit having such an airbag module

Abstract

The invention relates to an airbag module (22) for assembly on a steering device (10) that is rotatable about an axis (A) of a motor vehicle, having a module housing (24) for receiving a folded airbag (26), which module housing has a module base (30), and a metal spring (28) for latching the airbag module (22) on the steering device (10), which metal spring is preassembled on the module base (30) and has a latching section (32) that is elastically deflectable transversely to the axis (A), wherein a spacing holder (34) is provided on the module base (30), which spacing holder axially adjoins the latching section (32) of the metal spring (28) on a side of the metal spring facing the folded airbag (26) and is elastically deflectable together with the latching section (32) of the metal spring (28) in a deflection direction (x) extending transversely to the axis (A). Furthermore, the invention relates to a vehicle steering unit (12) having such an airbag module (22).

Description

[0001] This invention relates to an airbag module for mounting on a steering mechanism rotatable about axis A of a motor vehicle. The airbag module includes: a module housing for receiving a folded airbag, the module housing having a module bottom; and a metal spring for engaging the airbag module on the steering mechanism, the metal spring being pre-assembled on the module bottom and having a locking section resiliently deflectable laterally to the axis. Furthermore, the invention also includes a vehicle steering unit having such an airbag module.

[0002] The driver-side front airbag module is currently mostly positioned in the center of the steering mechanism, which is designed as a steering wheel, and particularly engages with the steering wheel hub. Such a locking connection has a certain axial clearance, for example, due to dimensional tolerances and to ensure reliable engagement, and / or due to material aging. Furthermore, the locking connection can limit the desired axial clearance to allow for relative movement and to trigger the vehicle horn when the airbag module is pressed downwards.

[0003] During operation, axial play in the locking mechanism can lead to unwanted noise generation on rough roads, during steering wheel vibrations, or when related locking components collide with each other. This noise can be audible / disturbing to vehicle occupants, especially when the relevant locking components are metal. Such noise is often due to safety requirements and the forces generated when the airbag module is deployed.

[0004] As in Figure 8 and Figure 9 As shown, it is known from the prior art that the locking element 20', designed as a locking pin, may have a (noise-reducing) plastic bushing 100 in the area of ​​its locking lug 40' to prevent direct contact between the locking pin and the metal spring 28'. However, the plastic bushing 100 must be manufactured separately and subsequently assembled onto the locking element 20', thereby undesirably increasing the manufacturing cost and expense of the vehicle steering unit 12'.

[0005] Therefore, the object of the present invention is to create an airbag module that, after being mounted on the steering control of a motor vehicle, reliably prevents or minimizes the generation of unwanted noise between the airbag module and the steering control during driving operation at a low cost.

[0006] According to the present invention, this objective is achieved by an airbag module of the type described at the outset, in which a spacer is provided at the bottom of the module. This spacer is axially adjacent to the locking section of the metal spring on the side of the metal spring facing the folded airbag and can elastically deflect together with the locking section in a deflection direction x extending transversely to axis A. The spacer provided at the bottom of the module serves to reduce noise when the airbag module is engaged, thereby eliminating the need for more costly noise reduction measures (such as the plastic bushings mentioned above).

[0007] In a preferred embodiment of the airbag module, the spacer retainer is integrally implemented with the bottom of the module, thus eliminating the need for manufacturing or assembly steps for a separate muffler.

[0008] Particularly preferably, the bottom of the module is a plastic component, especially an injection-molded part made of plastic. Plastic materials are generally well-suited for noise reduction, especially in preventing direct metal-to-metal contact between the metal spring and the (in most cases, also metallic) locking elements of the steering mechanism. By manufacturing it as an injection-molded part, a geometric fit to the bottom of the module, particularly for molding the spacer retainer, can be achieved at a negligible additional cost.

[0009] According to another embodiment of the airbag module, the spacer retainer has an axial protrusion that abuts a locking section of a metal spring in the deflection direction. During airbag module assembly, the locking section of the metal spring is force-applied and deflected in the deflection direction, for example, by a locking element of a steering mechanism. Here, the spacer retainer is connected via the axial protrusion such that the metal spring "drives" the spacer retainer in the deflection direction. Therefore, the locking section of the metal spring and the spacer retainer first jointly perform a deflection movement in the deflection direction and then perform an opposite locking movement, thus ensuring particularly reliable and reproducible engagement of the airbag module.

[0010] Preferably, the module has an axial bottom opening for receiving the locking elements of the steering mechanism, wherein the locking section of the metal spring and the spacer retainer extend into the opening section of the bottom opening. In this way, the airbag module can be easily, reliably, and with minimal structural space requirements locked onto the steering mechanism via axial assembly movement.

[0011] Furthermore, the present invention also includes a vehicle steering unit having the aforementioned airbag module and a steering operating device rotatable about axis A, wherein a (particularly metallic) locking element is provided on the steering operating device, the locking element having a locking lug for engaging with a metal spring of the airbag module, wherein, in the engaged state of the airbag module, a spacer retainer at the bottom of the module extends axially between the locking lug and the locking section of the metal spring. Therefore, the spacer retainer reliably prevents undesirable contact between the metal spring and (particularly also metallic) the locking lug, as well as the resulting contact noise. In contrast, especially when the spacer retainer is made of plastic, the possible contact noise between the spacer retainer and the locking lug and / or the metal spring is negligible.

[0012] According to one embodiment of the vehicle steering unit, the airbag module can be moved in a restricted axial direction relative to the steering operating device, for example for operating the vehicle horn, wherein a spring element is provided that applies force to the airbag module and the steering operating device to move them axially away from each other.

[0013] In this embodiment, the spring element may in particular be a helical compression spring arranged between the steering control device and the airbag module, the helical compression spring surrounding the locking element of the steering control device.

[0014] The locking element is preferably a separate locking pin fastened to the steering operating device, which extends axially and has a locking lug at the end toward the airbag module.

[0015] However, alternatively, the locking element can also be implemented integrally with the frame of the steering control device, wherein the locking element extends axially toward the airbag module and has a locking lug at its free axial end.

[0016] Other features and advantages of the invention will become apparent from the following description of preferred embodiments with reference to the accompanying drawings. In these drawings:

[0017] - Figure 1 An axial top view of the steering operation device of the vehicle steering unit according to the present invention is shown;

[0018] - Figure 2 An axial bottom view of the bottom of the airbag module according to the present invention is shown;

[0019] - Figure 3 A detailed cross-section of the vehicle steering unit according to the invention is shown before the airbag module engages with the steering operating device.

[0020] - Figure 4 It is shown that at the start of the locking process, according to Figure 3 Detailed cross-section of the vehicle steering unit;

[0021] - Figure 5 Shown at the end of the locking process according to Figure 3 Detailed cross-section of the vehicle steering unit;

[0022] - Figure 6 This is shown after the airbag module engages with the steering control device. Figure 3 Detailed cross-section of the vehicle steering unit;

[0023] - Figure 7 Show Figure 6 The image shows a top view of the locking connection of the vehicle steering unit.

[0024] - Figure 8 This shows a detailed cross-section of a conventional vehicle steering unit before the airbag module engages with the steering control mechanism; and

[0025] - Figure 9 This is shown after the airbag module engages with the steering control device. Figure 8 Detailed cross-section of a conventional vehicle steering unit.

[0026] Figure 1 A portion of the steering operating device 10 of a vehicle steering unit 12 for a motor vehicle is shown in an axial top view, wherein the steering operating device 10 is rotatable about axis A in its installed state. In the illustrated embodiment, the steering operating device 10 is designed as a steering wheel having a central hub 14, a surrounding rim 16, and spokes 18 for connecting the rim 16 to the hub 14.

[0027] According to Figure 1 The steering control device 10, specifically the hub 14, is provided with locking elements 20, which are used to secure the airbag module 22 to the central area of ​​the steering control device 10.

[0028] The airbag module 22, for mounting on the steering control device 10 rotatable about axis A, includes a means of receiving a folded airbag 26 (see [link]). Figure 3 and Figure 6 The module housing 24 and at least one metal spring 28 for engaging the airbag module 22 onto the steering control device 10. The module housing 24 has a module bottom 30, which is located on... Figure 2The hub 14 of the steering control device 10 is shown in an axial bottom view with the airbag module 22 already assembled. In this embodiment, three metal springs 28 are provided, which are pre-assembled on the bottom 30 of the module and each has a locking section 32 that can elastically deflect in a deflection direction x extending transversely to axis A.

[0029] As in Figure 2 As can be vaguely seen, a spacer retainer 34 is provided on the bottom 30 of the module, which axially abuts the locking section 32 of the designated metal spring 28 on the side facing the folded airbag 26 (see also...). Figures 3 to 6 It can also be elastically deflected together with the locking section 32 in a deflection direction x extending laterally to axis A. Specifically, in this embodiment, three spacer retainers 34 are provided, each of which is equipped with a metal spring 28.

[0030] according to Figure 2 The module bottom 30 has at least one axial bottom opening 36 for receiving the locking element 20 of the steering operating device 10, wherein the locking section 32 of the assigned metal spring 28 and the assigned spacer retainer 34 extend into the opening section of the at least one bottom opening 36. In this embodiment, specifically three axial bottom openings 36 are provided, each of which is assigned to either the metal spring 28 or the spacer retainer 34.

[0031] In the illustrated embodiment of the airbag module 22, the spacer retainer 34 is integrally formed with the bottom 30 of the module (see also...). Figures 3 to 6 The bottom 30 of the module is a plastic component, particularly an injection-molded part made of plastic.

[0032] Figure 3 A detailed cross-section of the vehicle steering unit 12 is shown in the area where the airbag module 22 and the steering operating device 10 are locked together (however, before they engage).

[0033] With the help of Figure 3 As can be clearly seen in the magnified image, a section of the spacer retainer 34 axially abuts the locking section 32 of the metal spring 28 on the side facing the folded airbag 26. Furthermore, it becomes apparent that the spacer retainer 34 has an axial protrusion 38 that abuts the locking section 32 of the metal spring 28 in the deflection direction x.

[0034] In the illustrated embodiment of the vehicle steering unit 12, the locking element 20 is a separate locking pin fastened to the steering operating device 10. This locking pin extends axially and has a locking lug 40 at its axial end toward the airbag module 22 for engaging with the metal spring 28 of the airbag module 22. At the opposite axial end, the locking pin is fastened in the region of the hub 14 to the steering operating device 10, and more particularly to the frame 42 of the steering operating device 10.

[0035] However, alternatively, it is conceivable that the locking element 20 is implemented integrally with the frame 42 of the steering operating device 10, wherein the locking element 20 extends axially toward the airbag module 22 and has a locking lug 40 at its axial end.

[0036] Due to the force generated when the airbag module 22 is triggered and the associated safety requirements, the locking element 20 and the locking lug 40 are made of metal, in particular, regardless of whether they are implemented separately as locking pins or integrated into the frame 42.

[0037] As in Figure 4 and Figure 5 As shown, by applying an axial assembly force F to the airbag module 22, the spacer retainer 34 and the locking section 32 of the metal spring 28 elastically deflect in the deflection direction x until the spacer retainer 34 and the locking section 32 of the metal spring 28 spring back in the opposite deflection direction x and according to... Figure 6 and Figure 7 The locking lug 40 engages with the locking element 20 at the rear.

[0038] With the help of Figure 6 As can be clearly seen in the magnified image, in the engaged state of the airbag module 22, a section of the spacer retainer 34 extends axially between the locking lug 40 and the locking section 32 of the metal spring 28. In this way, direct metal-to-metal contact between the metal spring 28 and the metallic locking lug 40 is avoided, and thus contact noise is prevented or at least significantly reduced.

[0039] In order to operate the vehicle horn, in the illustrated embodiment of the vehicle steering unit 12, the airbag module 22 is mounted to be axially movable relative to the steering operating device 10 in a restricted manner. According to... Figures 3 to 6A spring element 44 is provided, which applies force to the airbag module 22 and the steering mechanism 10 to axially move them away from each other. Specifically, the spring element 44 is a helical compression spring arranged between the steering mechanism 10 and the airbag module 22, surrounding the locking element 20. To operate the vehicle horn, the airbag module 22 must move axially toward the steering mechanism 10 against the spring force of the helical compression spring, wherein the locking section 32 of the metal spring 28 slides axially along the locking pin in the region where the cross-section of the locking pin decreases.

Claims

1. An airbag module for mounting on a steering control device (10) rotatable about an axis (A) of a motor vehicle, the airbag module having: A module housing (24) for receiving a folded airbag (26), the module housing having a module bottom (30); and A metal spring (28) for engaging the airbag module (22) with the steering operating device (10) is pre-assembled on the bottom (30) of the module and has a locking section (32) that is elastically deflectable transversely to the axis (A). Its features are, A spacer retainer (34) is provided on the bottom (30) of the module. The spacer retainer is axially adjacent to the locking section (32) of the metal spring (28) on the side facing the folded airbag (26) and is capable of elastically deflecting together with the locking section (32) of the metal spring (28) in a deflection direction (x) extending transversely to the axis (A). The spacer retainer (34) is integrally implemented with the bottom (30) of the module.

2. The airbag module according to claim 1, characterized in that, The bottom (30) of the module is a plastic component.

3. The airbag module according to claim 2, characterized in that, The bottom (30) of the module is an injection-molded part made of plastic.

4. The airbag module according to any one of claims 1 to 3, characterized in that, The spacer retainer (34) has an axial protrusion (38) that is adjacent to the locking section (32) of the metal spring (28) in the deflection direction (x).

5. The airbag module according to any one of claims 1 to 3, characterized in that, The bottom (30) of the module has an axial bottom opening (36) for receiving the locking element (20) of the steering operation device (10), wherein the locking section (32) of the metal spring (28) and the spacer (34) both extend into the opening section of the bottom opening (36).

6. A vehicle steering unit, comprising: The airbag module (22) according to any one of claims 1 to 5; and A steering operating device (10) rotatable about axis (A), on which a locking element (20) is provided, the locking element having a locking lug (40) for engaging with a metal spring (28) of the airbag module (22). In the state where the airbag module (22) is engaged, the spacer retainer (34) at the bottom (30) of the module extends in the axial direction between the locking lug (40) and the locking section (32) of the metal spring (28).

7. The vehicle steering unit according to claim 6, characterized in that, The airbag module (22) is axially restricted relative to the steering control device (10), wherein a spring element (44) is provided, which applies force to the airbag module (22) and the steering control device (10) to move them axially away from each other.

8. The vehicle steering unit according to claim 7, characterized in that, The spring element (44) is a helical pressure spring arranged between the steering operation device (10) and the airbag module (22), the helical pressure spring surrounding the locking element (20).

9. The vehicle steering unit according to any one of claims 6 to 8, characterized in that, The locking element (20) is a separate locking pin fastened to the steering operating device (10), the locking pin extending in the axial direction and having the locking lug (40) at the end toward the airbag module (22).

10. The vehicle steering unit according to any one of claims 6 to 8, characterized in that, The locking element (20) is integrally implemented with the frame (42) of the steering operating device (10), wherein the locking element (20) extends axially toward the airbag module (22) and has the locking lug (40) at its free axial end.

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