The invention relates to an attachment element for fastening an airbag comprising the features of the preamble of claim 1.

Nowadays, various airbags are provided in modern vehicles, which airbags are rapidly inflated during an accident and pro ^¬ tect the passenger or the pedestrian against hitting the areas of the vehicle structure covered by the airbag or the compo ^¬ nents covered by the same like steering wheels, backrests etc. The fastening of the airbags to the vehicle structure is sub ^¬ ject to various legal requirements and additional requirements on the part of the vehicle manufacturer as to the load capaci ^¬ ty under various conditions. Moreover, the fastening shall na ^¬ turally be realized as assembly-friendly and as cost-effective as possible.

The attachment of the airbag can be realized for example by a clamping element with a clamping ring which is fixed via a screw or a bolt to the vehicle structure. For the fixation of the screw, a nut needs to be fixed at the vehicle structure, which is usually realized by a welded nut. The welded nut in ^¬ creases the costs and the design effort at the vehicle manu ^¬ facturer .

From the EP 1 422 112 Al and the WO 2006/108889 Al are known different attachment elements, which comprise a clamping me ^¬ chanism which is widened up after the positioning of the attachment element in the attachment opening of the vehicle by inserting a pin. The pin is designed as a bolt with a diameter greater than the diameter of an opening in the clamping mecha- nism, so that hooks of the clamping mechanism are pressed out ^¬ wardly when the pin bolt is inserted. The fixation of the at ^¬ tachment element and the airbag is realized then by clamping the rim of the opening of the vehicle structure between the hooks and an attachment plate. One disadvantage of these at ^¬ tachment elements is that these attachment elements may also be attached incorrectly when the attachment element is not in ^¬ serted completely and the rim of the vehicle structure is not clamped properly between the hooks and the attachment plate.

In light of this, it is the object of the invention to provide an attachment element, which shall enable an easy handling for the operator during the mounting process of the airbag.

The solution of the object is provided by an attachment ele ^¬ ment comprising the features of claim 1. Preferred develop ^¬ ments of the invention can be learned from the sub claims.

According to claim 1, it is suggested that the hook comprises a thickened head extending at one side of the hook, and the through-hole is running at least in sections in an angle un ^¬ equal to 90 degrees with respect to the attachment plate, and wherein the through-hole ends in an opening, which is located at the side of the hook opposing to the thickened head.

The advantage of the suggested solution can be seen therein, that the attachment screw or bolt is pressing the hook with the thickened head automatically into the clamping position because of the angled through-hole and the location of the opening, where the through-hole ends. The angle of the

through-hole obliges the attachment element to a side movement when the attachment bolt or screw is inserted and abuts at a vehicle-fixed part (for example by abutting at the rim of the attachment opening in the vehicle structure) . The movement of the hook into the clamping position is realized in this case by a pure pivoting movement of the hook without deforming the attachment element in itself. Therefore, the suggested attach ^¬ ment element does not need to be flexible or elastic in itself and it can be used a material with a high strength like metal or the like for the attachment element. The further advantage of the suggested solution can be seen therein, that no welded nut is needed at the vehicle structure as the suggested at ^¬ tachment element comprises already the through-hole with a thread to fix the screw. The attachment element combines the advantages of a clip element with the advantages of a screw, wherein both fixation elements are acting together in this design to improve the attachment with using only one element.

Furthermore, it is suggested that the hook comprises an abut ^¬ ment surface which is shaped at least in sections correspon ^¬ ding to the outer surface of the attachment screw or bolt. The attachment screw or bolt presses the hook into the clamping position by getting into contact with the rim of the attachment opening of the vehicle and abutting at the same time at the hook. As the hook comprises the suggested abutment surface having at least in sections a corresponding surface, it is possible to guide the attachment screw or bolt during the in ^¬ sertion movement and to assure that the whole attachment ele ^¬ ment is pivoted and not only the attachment screw or bolt.

The guidance can be further improved when the abutment surface at the hook is designed as a prolongation of a part of the side wall of the through-hole in the attachment element. The attachment screw or bolt is inserted in a first step into the through-hole which obliges the attachment element in a prede ^¬ fined orientation. As the abutment surface at the hook is de- signed as a prolongation of the through-hole, the attachment element gets automatically into contact with the abutment sur ^¬ face and is guided during the further movement especially while pressing the hook into the clamping position.

It has shown in various tests that the angle should be pre ^¬ ferably between 70 and 85 degrees to enable an easy handling with providing the necessary forces to move the hook into the clamping position.

Furthermore, it is suggested that the hook is designed with dimensions enabling the insertion of the attachment element with the hook into the attachment opening only when the at ^¬ tachment screw or bolt is not inserted into the through-hole. The suggested dimensioning of the hook prevents an incorrect attachment of the attachment element, since the attachment process is clearly differenced into two separated steps, with an insertion of the attachment element with the hook into the attachment opening in a first step and an insertion of the at ^¬ tachment screw or bolt into the attachment element with urging the hook into the clamping position in a second step.

Furthermore, it is suggested that the hook is shaped with a pointed head, which is inserted first into the attachment opening of the vehicle for fastening the attachment element. The suggested shape of the head of the hook enables an easy mounting and especially the insertion in a first step with a part of the hook together with the attachment screw or bolt into the attachment opening. In a second step, the attachment element is pivoted into a predetermined position, where the attachment element is fixed finally. The pivoting movement is enabled in a first step by the shape of the pointed head with an angled surface at one side and, in a second step, by in- - b -

serting the screw or bolt further into the through-hole. The pointed head can be designed with one or two angled surfaces, where the term angled relates to an angle with respect to the length axis of the hook. The angle is an acute angle between the length axis and the surface.

Another preferred embodiment can be provided when the hook is located excentrically at the attachment plate, and the thick ^¬ ened head of the hook is directed to the longer side of the attachment plate. The excentric arrangement providing a longer side provides in combination with the thickened head directed to the longer side a further guidance of the movement of the attachment element as the attachment plate abuts with the rim of the longer side at the vehicle structure.

Moreover, it is suggested that the through-hole comprises a first section which is oriented perpendicular to the attachment plate, and a second section which is oriented in the an ^¬ gle. The attachment screw or bolt can be inserted as usual in a first step perpendicular into the attachment element for ex ^¬ ample into a transport position. The pivoting movement will be obliged in the second step when the attachment screw or bolt is screwed or inserted further into the through-hole.

Furthermore, it is suggested that the hook comprises at least in a section a not-round shaped cross-section which corresponds to the shape of the attachment opening. The suggested shape of the hook prevents a not intended turning movement of the attachment element with respect to the attachment opening. The section with the not-round shape is the section close to the attachment plate which will be located in the attachment opening after the fastening. With dimensioning the hook in this section equal or close to the dimensions of the attach- ment openings, rattling noises and other movements can be fur ^¬ ther prevented.

In the following, the invention shall be illustrated on the basis of preferred embodiments with reference to the accompa ^¬ nying drawings, wherein:

Fig. 1 shows an attachment element;

Fig. 2 shows a clamping element;

Fig. 3 shows a cross-section through the attachment element before the hook is pressed into the clamping posi ^¬ tion;

Fig. 4 shows a cross-section through the attachment element when the hook is pressed into the clamping position;

Fig. 5 shows an attachment element without the attachment screw or bolt;

Fig. 6 shows an attachment element with a through-hole hav ^¬ ing two different sections.

In Figure 1, it is shown an attachment element 1 designed ac ^¬ cording to the present invention having an attachment plate 8 with a hook 6 extending from one side and an attachment screw 7 extending from the other side.

In Figure 2, it is shown a clamping element 2 comprising a flexible clamping ring 3 made of plastic, which is formed at the end sections as flat sections 4 and 5. In each of the flat sections 4 and 5 is arranged one opening 13 and 14 which are aligned to one through-hole 15 when the flat sections 4 and 5 are arranged as designated, like shown in Figure 4. The clam ^¬ ping ring 3 is designed to be looped around the tubular-shaped airbag, like for example a rolled or folded curtain airbag or pedestrian airbag.

In Figure 3, it is shown the attachment element 1, which is inserted into a through-hole 15 provided by the aligning open ^¬ ings 13 and 14 in the flat sections 4 and 5. The attachment element 1 may be prefixed at one of the flat sections 4 or 5 of the clamping element 2 as a pre-assembled unit together with the airbag. The clamping element 2 is inserted with the attachment element 1 into an attachment opening 11 in the ve ^¬ hicle structure 10, wherein the attachment element 1 is in ^¬ serted in a first step with the hook 6, until the hook 6 en ^¬ gages with a thickened head 12 completely into the opening 11. In a second step, the attachment screw 7 is screwed into a through-hole 17 of the attachment element 1, until the attach ^¬ ment screw 7 is abutting at a rim 16 at one side of the opening 11. The thickened head 12 of the hook 6 is dimensioned in a size which enables only the insertion of the head 12. The through-hole 17 and the inserted attachment screw 7 are ori ^¬ ented in an angle B with respect to the attachment plate 8 un ^¬ equal to 90 degrees. The angle B is shown in Figure 3 as the angle between the length axis L of the attachment screw 7 and a plane defined by the attachment plate 8.

When the attachment screw 7 is further inserted or screwed in ^¬ to the opening 11, a pivoting movement of the attachment ele ^¬ ment 1 in arrow direction A is obliged by pressing the attachment screw 7 against the rim 16 and urging the hook 7 into the clamping position shown in Figure 4. The pivoting movement of the attachment element 1 is guided by the attachment screw 7 which is abutting with a shaft 7a at a side surface 18 of the hook 6 shown in Figure 1, which is a prolongation of one side of the through-hole 17. If the shaft 7a is provided with a thread, it is reasonable to provide also the side surface 18 with a thread, to increase the connecting surface between the attachment screw 7 and the hook 6.

As the hook 6 is inserted in the first step with the thickened head 12 into the opening, the inserting movement is further supported by the head 12 which is overlapping the rim of the opening 11 at least partially and prevents therefore that the head 12 is pulled out of the opening 11, while screwing the attachment screw 7 into the through-hole 17.

In Figure 5, it is shown an attachment element 1 without the attachment screw or bolt 7. The hook is arranged excentrically dividing the attachment plate 8 into two sides 8a and 8b ha ^¬ ving different lengths. The side 8a with the greater length is directed at the same side like the thickened head 12 extending from the hook 6 at one side. The hook 6 comprises further a pointed head 6a which facilitates the insertion movement of the hook 6 into the attachment opening 11 by providing at least at one side an angled surface which encloses an acute angle with the length axis of the hook 6.

In Figure 6, it is shown the attachment element 1 with an at ^¬ tachment screw 7 in different positions. The through-hole 17 is designed with two sections 17a and 17b, wherein the section 17a is oriented perpendicular to the plane of the attachment plate 8 and the section 17b is oriented in the angle B shown in Figure 3. The attachment screw 7 performs therefore a move ^¬ ment in two different directions, until the complete insertion into the through-hole 17.