WO2021122047A1

WO2021122047A1 - Airbag cover, airbag module having the airbag cover, vehicle having the airbag module and method for manufacturing an airbag cover

Info

Publication number: WO2021122047A1
Application number: PCT/EP2020/084553
Authority: WO
Inventors: Jürgen Maier
Original assignee: Psa Automobiles Sa
Priority date: 2019-12-17
Filing date: 2020-12-03
Publication date: 2021-06-24
Also published as: DE102019219787A1; EP4077064A1

Abstract

The invention relates to an airbag cover (1) for an airbag module of a vehicle, said airbag cover (1) comprising a supporting device (2), wherein a tear line (5) is integrated into the supporting device (2), along which the supporting device (2) can tear at the moment of and/or during an impact of the vehicle and can clear the way for the airbag of the airbag module to expand. The supporting device (2) with the integrated tear line (5) is formed from an injection-moulded base material (3), the airbag cover (1) comprises a cover film (8), a weakening line (11) is introduced into the cover film (8) and the cover film (8) is back-moulded with the base material (3).

Description

AIRBAG COVER, AIRBAG MODULE WITH THE AIRBAG COVER, VEHICLE WITH THE AIRBAG MODULE AND METHOD FOR MANUFACTURING A

AIRBAG COVER

Technical area:

The invention relates to an airbag cover for an airbag module of a vehicle with the features of claim 1 and an airbag module with the airbag cover. The invention further relates to a vehicle with the airbag module and a method for producing an airbag cover for an airbag module of a vehicle.

Background:

An airbag cover is often designed as a plastic component, on the rear side of which a tear line is made, along which the airbag cover can tear open in the event of a collision with the vehicle in order to enable an airbag to be deployed to protect an occupant. A visible side of the airbag cover is usually formed from a grained plastic material, which is not visually appealing. For this reason, options are being sought to make the visible side more valuable. It is already known to provide a decorative film for the airbag cover, in which an invisible line of weakness is introduced in order to enable it to be torn open.

For example, the publication DE 10 055 546 C2, which probably forms the closest prior art, describes an airbag cover with weakening structures and a method for their production. The airbag lining consists of a decorative film with weakening structures on the inside, the weakening structures not being visible on the outside. The weakening lines are made with an embossing tool, e.g. a knife blade.

Description:

The invention is based on the object of providing a functional, visually appealing and easy-to-manufacture airbag cover. This object is achieved by an airbag cover for an airbag module of a vehicle with the features of claim 1, by an airbag module with the airbag cover according to claim 8 Vehicle with the airbag module according to claim 10 and achieved by a method for producing an airbag cover for an airbag module of a vehicle with the features of claim 11. Preferred or advantageous embodiments of the invention emerge from the subclaims of the following description and / or the attached figures.

An airbag cover for an airbag module of a vehicle is proposed. For example, the vehicle is a car or a truck. The airbag module can be accommodated in a receiving space in an interior of the vehicle. To protect a driver of the vehicle, the airbag module can be integrated in a steering wheel, to protect a passenger of the vehicle in a dashboard or to protect the driver, the passenger and / or at least one other occupant in a ceiling, door or wall paneling.

The airbag cover preferably covers the airbag module when the airbag module is accommodated in the accommodation space of the interior equipment. The interior is designed as the steering wheel or the dashboard, for example. It can also be designed as an instrument panel, as a door inside, roof inside or wall inside. For example, the airbag cover is designed as a lining component for lining the interior fittings. In particular, the airbag cover can be arranged as the lining component between further lining components for lining the interior fittings.

The airbag cover comprises a carrier device. The carrier device is preferably a plastic component. The plastic component can, for example, comprise polyolefins, in particular polypropylene, or be formed from these. A tear line is integrated into the carrier device. During and / or during a collision of the vehicle, the carrier device can tear open along the tear line and clear a path for an inflating airbag of the airbag module. The carrier device and the tear line integrated therein are formed from an injection-molded base material. The base material is, in particular, a granulate or a powder. The granules or the powder preferably comprise plastic components or are formed from these.

The airbag cover comprises a cover sheet. The cover film preferably covers the airbag cover. The carrier device preferably carries the cover film. Especially the cover film is a decorative film. The decorative film preferably has a visually appealing, for example high-gloss, visible side. A line of weakness is introduced into the cover film. The line of weakness advantageously enables the airbag cover to be torn open in the event of a vehicle impact. For this purpose, the line of weakness in the cover film preferably interacts with the tear line in the carrier device.

According to the invention, the cover film is back-injected with the base material. The cover film is preferably materially connected to the carrier device injection-molded from the base material. In particular, the carrier device can be injection-molded from the base material, the cover film being attached to the carrier device in the same manufacturing step. In particular, for this purpose the cover film is inserted into a tool of the injection molding machine and back-injected therein with the base material of the carrier device.

It is advantageous that the airbag cover can be produced simply and inexpensively in the injection molding machine. In particular, a secure, clean and visually appealing connection between the cover film and the carrier device can thereby be achieved.

In one possible embodiment of the invention, the cover film is designed as a single layer. The preferably single-layer cover film preferably has a rear side and a visible side. The base material is preferably back-molded on the back of the cover film. In particular, the rear side of the cover film is arranged on the carrier device and / or connected to the carrier device on the rear side. In particular, only the visible side of a vehicle interior is thus visible when the airbag cover covers the airbag module integrated in the interior of the vehicle.

In a possible structural embodiment of the invention, the line of weakness is introduced into the rear side of the cover film. For example, the weakening line is a laser cut, needling, a milling line, a stamp line or a cutting line in the back of the cover film. The line of weakness can be continuous and uninterrupted. Alternatively, the line of weakness can be designed as a raster line.

It is also preferred within the scope of the invention that the line of weakness is not visible on the visible side. Preferably the line of weakness is in the back introduced that it cannot be seen from the visible side. In particular, the cover film has a sufficient thickness that allows the line of weakness to be introduced into the rear side and at the same time not be recognizable on the visible side. For example, this can be achieved in that the weakening line has a depth which is a maximum of 50 percent of the thickness of the cover film, preferably a maximum of 75 percent of the thickness of the cover film.

Alternatively or optionally in addition, the tear line integrated in the carrier device cannot be seen and / or invisible from the visible side of the cover film. The thickness of the cover film is preferably selected so that the tear line does not leave an imprint on the visible side.

It is advantageous that the visible side is continuously smooth despite the weakening line on the back and / or despite the tear line in the carrier device underneath and does not have any optical disruptive factors caused by the weakening line and / or the tear line. Thus, an airbag cover can be provided which has a visually appealing and high-quality visible side.

In a possible structural implementation of the invention, the cover film is arranged on the carrier device and / or back-injected with the base material in such a way that the weakening line is at least overlapping, preferably congruent with the tear line. As a result, a protective function of the airbag integrated in the airbag module can be reliably ensured in an advantageous manner. Because if the airbag cover tears open along the tear line in the event of a collision with the vehicle, the forces acting in the process also tear the cover sheet along the line of weakness, so that the way is cleared for the inflating airbag.

Another object of the invention is an airbag module for a vehicle. The airbag module comprises the airbag cover according to the previous description and / or according to one of claims 1 to 7. The airbag module preferably has an airbag, the airbag being accommodated, for example, in a module housing of the airbag module. In particular, the module housing of the airbag module is covered with the airbag cover. Optionally in addition, the airbag module comprises at least one gas generator for releasing gas in the event of a collision with the vehicle. The airbag is preferably filled with the gas in such a way that it expands like an explosion in the module housing, with the airbag cover along the tear line and the cover film along the Line of weakness are torn.

For example, the airbag is designed as a driver airbag to protect the driver of the vehicle, as a passenger airbag to protect the passenger of the vehicle or as a side airbag to protect the driver, passenger and / or the at least one other occupant.

A vehicle with the airbag module according to the previous description and / or according to one of claims 8 or 9 forms a further subject matter of the invention.

Another object of the invention is a method for producing an airbag cover for an airbag module of a vehicle. A cover sheet is provided as part of the process. A line of weakness is introduced into the cover film. For example, the line of weakness is lasered, needled, milled or stamped into the cover film. Alternatively, the line of weakness is introduced into the cover film with a drawn cold knife.

The cover film is placed in an injection molding machine, for example a plastic injection molding machine, and a base material is back-injected there. A carrier device with an integrated tear line is formed from the base material. The cover film preferably has a rear side and a visible side. The base material is preferably back-injected onto the back of the cover film.

In one possible process step, the line of weakness is introduced into the back of the cover film before the cover film is inserted into the injection molding machine. The weakening line is introduced into the rear side, for example, with a processing tool that is separate from the injection molding machine. For example, the processing tool is a laser, a needle, a milling cutter, a stamp, or a so-called cold knife. The weakening line is preferably introduced into the rear side in such a way that it is invisible on the visible side and / or that it cannot be seen on the visible side.

In the context of the invention, it is particularly preferred that the cover film has a sufficient thickness so that the weakening line can be introduced on the rear side and is nevertheless not visible on the visible side. Alternatively or optionally in addition, the cover film has sufficient thickness for the tear line to be does not push the carrier device through the cover film and / or that the tear line of the carrier device is not visible on the visible side.

In summary, the cover film is made sufficiently strong that the tear line and the weakening line cannot be seen from the visible side. As a result, a visually appealing airbag cover with a high-quality visible side without disruptive contours and unevenness can be provided.

In a further possible method step, the base material is back-injected into the cover film in such a way that the tear line runs at least overlapping, preferably congruently with the weakening line.

Further features, advantages and effects of the invention emerge from the following description of preferred exemplary embodiments of the invention. Show:

Figure 1 is a plan view from above of a carrier device

Airbag cover, a tear line being made in the carrier device;

FIG. 2 shows a perspective top view of a cover film of the airbag cover;

Figure 3 is a longitudinal section through a detail of the airbag cover with the

Carrier device and with the cover sheet;

FIGS. 4a-4d different process steps for producing the airbag cover.

Corresponding or identical parts are provided with the same reference numerals in the figures.

FIG. 1 shows a plan view of an upper side of a carrier device 2 of an airbag cover 1 (FIG. 3) for an airbag module of a vehicle. The airbag module comprises an airbag, which can be designed as a driver airbag, front passenger airbag or side airbag. For this purpose, the airbag module can be integrated in an interior of the vehicle, for example in a steering wheel, a dashboard, an instrument panel or in a door, wall or ceiling paneling of the vehicle. The Airbag cover 1 forms a trim part for covering the interior of the vehicle.

The carrier device 2 is designed as a plastic component, for example made of polyolefins. It has a substantially crest-shaped outer contour. In alternative exemplary embodiments, the carrier device can also have other outer contours. These are particularly dependent on the position and function of the airbag, the airbag module of which comprises the airbag cover 1 with the carrier device 2.

The carrier device 2 is formed from an injection-molded base material 3. The base material 3 is a plastic granulate or a plastic powder which is processed, in particular melted, in a plastic injection molding machine 4 and from which the carrier device 2 can be injected.

The carrier device 2 has a tear line 5. The tear line 5 is integrated into the carrier device 2 in a materially bonded manner. In the plastic injection molding machine 4, the tear line 5 is correspondingly integrated during the injection molding of the carrier device 2. As can be seen in a longitudinal section through the carrier device 2 according to FIG. 3, the tear line 5 is arranged on an underside of the carrier device 2 and is designed as a taper in a base body 6 of the carrier device 2.

During and / or during a collision of the vehicle, the carrier device 2 tears open along the tear line 5, so that the airbag can inflate in the direction of the driver, the front passenger or the at least one other occupant for protection.

FIG. 2 shows a perspective top view from above onto a visible side 9 of a cover film 8 of the airbag cover 1. The cover sheet 8 is a single-layer sheet cut. It has the visible side 9 and a rear side 10. The cover film 8 is designed as a decorative film, the visible side 9 being designed in a visually appealing manner. The visible side 9 is, for example, high-gloss.

FIG. 3 shows a longitudinal section along the section line A-A through the carrier device 2 and through the cover film 8 fastened on the carrier device 2, which together form the airbag cover 1.

A line of weakness 11 is introduced into the cover film 8. The line of weakness 11 is With a processing tool 12 (FIG. 4 a), for example with a laser, a stamp, a needle, a milling cutter or a so-called cold knife, introduced into the rear side 10 of the cover film 8.

The cover film 8 covers the carrier device 2, in particular the base body 6 formed by the base material 3. For this purpose, the cover film 8 is arranged with the rear side 10 on the upper side of the carrier device 2. On the back, the cover film 8 is back-molded with the base material 3, so that the cover film 8 is connected to the carrier device 2, in particular to the base body 6, in a materially bonded manner.

The cover film 8 is back-injected with the base material 3 in such a way that the weakening line 11 and the tear line 5 are arranged at the same height in the longitudinal section of FIG. 3 and are arranged congruently in a top view of the cover 1. As a result, a tear-open function of the airbag cover 1 during and / or during the impact of the vehicle can be reliably ensured.

The cover film 8 has a thickness which enables the weakening line 11 to be invisible on the visible side 9. For this purpose, the weakening line 11 has a depth which is a maximum of 50 percent of the thickness of the cover film 8, preferably a maximum of 75 percent of the thickness of the cover film 8.

The cover film 8 is also designed to be sufficiently strong that the tear line 5 cannot push through the cover film 8 and become visible on the visible side. The cover film 8 is thus continuously smooth on the visible side 9, in particular without disruptive contours, which are caused in particular by the weakening line 11 or by the tear line 5.

Several method steps of a method for producing the airbag cover 2 are shown in FIGS. 4a to 4d.

According to FIG. 4a, the cover sheet 8 is provided with the rear side 10 facing up. With the processing tool 12, the line of weakness 11 is introduced into the rear side 10 of the cover film 8. The weakening line 11 is introduced into the rear side 10 in such a way that its course corresponds to and / or follows the later course of the tear line 5 of the airbag cover 2 and that it cannot be seen on the visible side 9. The line of weakness 11 is introduced with the machining tool 12 in such a way that it has a maximum depth of 50 percent, preferably 75 percent of the thickness of the cover sheet 8.

According to FIG. 4b, the cover film 8 provided with the line of weakness 11 is provided for back-injection molding with the base material 3 in the plastic injection molding machine 4. The cover film 8 is placed in an open mold 13 of the plastic injection molding machine 4. The base material 3 is provided as the granulate or powder and fed to a heating and injection device 14 of the plastic injection molding machine 4.

As shown in Figure 4d, the base material 3 is heated and liquefied and injected into the now closed mold 13, so that the cover sheet 8 is back-injected with the base material 3 and at the same time the carrier device 2, in particular its base body 6, with the integrated tear line 6 through the Base material 3 is formed.

The molding tool is designed in such a way that the integrated tear line 6 is injected overlapping, preferably congruent, with the weakening line 11 in the cover film 8. The cover film 8 is materially connected to the base body 6 during the back injection.

As shown in FIG. 4d, the carrier device 2 and the cover film 8 connected to it in a materially bonded manner form the airbag cover 1 which, after cooling, is ejected from the tool and removed from the plastic injection molding machine.

While at least one exemplary embodiment has been disclosed in detail above, it is to be recognized that a large number of variations according to the invention exist. It is also to be recognized that the at least one exemplary embodiment is only an example and does not represent any limitation of the scope of protection, the areas of application or the configuration. Rather, the present disclosure is intended to be a convenient roadmap for implementing at least one exemplary embodiment. Thus, it should be recognized that various variations in the function or arrangement of the elements of the at least one exemplary embodiment can be implemented without departing from the scope defined by the claims and their legal equivalents. List of reference symbols:

1 airbag cover

2 carrier device 3 base material

4 plastic injection molding machine

5 tear line

6 base bodies

7 underside 8 cover sheet

9 visible side

10 back

11 line of weakness

12 Machining tool 13 Forming tool

14 Heating and injection device

Claims

Patent claims:

1. Airbag cover (1) for an airbag module of a vehicle, the airbag cover (1) comprising a carrier device (2), a tear line (5) being integrated into the carrier device (2), along which the carrier device (2) at and / or can tear open during an impact of the vehicle and free a path for an inflating airbag of the airbag module, wherein the carrier device (2) with the integrated tear line (5) is formed from an injection-molded base material (3), the airbag cover (1) being a Cover film (8), a weakening line (11) being introduced into the cover film (8), the cover film (8) being back-molded with the base material (3).

2. Airbag cover (1) according to claim 1, wherein the cover film (8) is formed in one layer, the cover film (8) having a rear side (10) and a visible side (9), the cover film (8) on the rear side (10 ) is back-molded with the base material (3).

3. Airbag cover (1) according to claim 1 or 2, wherein the line of weakness (11) is introduced into the rear side (10).

4. Airbag cover (1) according to one of the preceding claims, wherein the weakening line (11) and / or the tear line (5) on the visible side (9) is invisible and / or not recognizable.

5. Airbag cover (1) according to one of the preceding claims, wherein the cover film (8) is arranged on the carrier device (2) and / or is back-injected with the base material (3) that the weakening line (11) overlaps and / or congruently is arranged with the tear line (5).

6. Airbag cover (1) according to one of the preceding claims, wherein the weakening line (11) is a laser cut, needling, a milling line, a stamp line or a cutting line.

7. Airbag cover (1) according to one of the preceding claims, wherein the carrier device (2) is a plastic component and / or wherein the base material (3) is a granulate or a powder, wherein the granulate or the powder comprises or is formed from plastic components .

8. Airbag module for a vehicle, wherein the airbag module comprises the airbag cover (1) according to one of claims 1 to 7.

9. The airbag module according to claim 13, wherein the airbag module comprises an airbag, the airbag being designed as a driver airbag, passenger airbag or side airbag.

10. Vehicle with the airbag module according to claim 8 or 9.

11. A method for producing an airbag cover (1) for an airbag module of a vehicle, a cover film (8) being provided, a line of weakness (11) being introduced into the cover film (8), the cover film (8) being fed into an injection molding machine ( 4) is inserted, the cover film (8) being back-injected with a base material (3) in the injection molding machine (4), a carrier device (2) with an integrated tear line (5) being formed from the base material (3).

12. The method according to claim 11, wherein the cover film (8) has a rear side (10) and a visible side (9), the weakening line (11) before the cover film (8) is inserted into the injection molding machine (4) in the rear side ( 10) is introduced.

13. The method according to claim 11 or 12, wherein the weakening line (11) is introduced into the rear side (10) that it is not visible and / or invisible on the visible side (9).

14. The method according to any one of claims 11 to 12, wherein the weakening line (11) is lasered, needled, milled or stamped into the cover film (8) or with drawn cold knife is introduced.

15. The method according to any one of claims 11 to 14, wherein the cover film (8) is back-injected with the base material (3) so that the tear line (5) overlaps and / or runs congruently with the weakening line (11).