METHOD FOR MANUFACTURING A GAS BAG MODULE OF A VEHICLE OCCUPANT RESTRAINT SYSTEM, AND GAS BAG MODULE

Abstract

It is provided a method for manufacturing a gas bag module of a vehicle occupant restraint system. The method comprising the steps: providing a gas bag; prefolding the gas bag; pressing at least a portion of the prefolded gas bag under the influence of heat; and folding the pressed gas bag to a final dimension.

Claims

1. A method for manufacturing a gas bag module of a vehicle occupant restraint system, comprising: providing a gas bag; prefolding the gas bag; pressing at least a portion of the prefolded gas bag under the influence of heat; and folding the pressed gas bag to a final dimension.

2. The method according to claim 1, wherein prefolding of the gas bag comprises roll-folding of a portion of the gas bag.

3. The method according to claim 1, wherein the prefolded gas bag includes at least one first and one second portion, wherein the first portion is unfolded or has a convolution other than the second portion.

4. The method according to claim 3, the second portion is roll-folded and/or zigzag-folded.

5. The method according to claim 3, wherein pressing of the prefolded gas bag comprises pressing of the second portion, while the first portion is pressed only partly or not at all.

6. The method according to claim 3, wherein pressing of the prefolded gas bag comprises pressing of the entire prefolded gas bag.

7. The method according to claim 3, wherein after pressing the first and the second portion of the prefolded gas bag are at least partly folded onto each other.

8. The method according to claim 2, wherein the first portion forms a receiving region for accommodating a gas generator.

9. The method according to claim 8, wherein the receiving region has an introduction opening into which the gas generator can be introduced.

10. The method according to claim 8, wherein the receiving region is pressed not at all.

11. The method according to claim 8, wherein the first portion includes at least one fastening opening for fastening the gas generator.

12. The method according to claim 3, wherein after the pressing, a gas generator is introduced into an introduction opening and thereafter the gas bag is folded into its final dimension by folding the first and the second portion of the gas bag at least partly onto each other.

13. The method according to claim 1, wherein the gas bag folded to the final dimension is provided with at least one fixing element which counteracts folding apart of the gas bag.

14. The method according to claim 13, wherein the fixing element is a fixing strap.

15. The method according to claim 1, wherein the gas bag folded to the final dimension is arranged in a housing.

16. The method according to claim 15, wherein the housing is a softcover or a hardcover.

17. The method according to claim 1, wherein pressing of the portion of the prefolded gas bag is effected under the influence of moisture.

18. A gas bag module for a vehicle occupant restraint system, which in particular is manufactured by the method according to claim 1, comprising a folded gas bag which includes a portion pressed under the influence of heat and an unpressed portion.

19. The gas bag module according to claim 18, wherein in the unpressed portion a gas generator for inflating the gas bag is arranged.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The invention will be explained in detail below with reference to exemplary embodiments.

[0023] FIGS. 1 to 3 show views of a gas bag from above at different times during the execution of the method according to the invention.

[0024] FIGS. 4 to 6 show the gas bag of FIGS. 1 to 3 in a perspective view.

DETAILED DESCRIPTION

[0025] FIG. 1 (FIG. 4) shows a gas bag 1 in a prefolded condition. In this prefolded condition the gas bag 1 comprises a first and a second portion 11, 12, wherein the first portion 11 merely is folded over once (i.e. merely includes a single fold 111), while the second portion 12 is roll-folded. It is also conceivable that the first portion 11 includes more than one fold, or also that the first portion 11 is not folded at all. In addition, the second portion 12 might also include a zigzag fold or a combination of a roll fold and a zigzag fold.

[0026] The first portion 11 of the prefolded gas bag 1 furthermore comprises a receiving region 20 for accommodating a gas generator. The receiving region 20 has an introduction opening 21 into which the gas generator can be introduced (cf. FIG. 3 and FIG. 6). In the receiving region 20 there can also be provided fastening openings for fastening the gas generator, which for example serve to lead through fastening bolts of the gas generator.

[0027] The prefolded gas bag 1 is pressed under the influence of heat and moisture, namely such that pressing of the complete second portion 12, but only of a section 112 of the first portion 11 adjoining the second portion 12 is effected. Another section 113 of the first portion 11, in which the introduction opening 21 is formed, is not pressed however (cf. FIG. 2 and FIG. 5) in order to facilitate the arrangement of the gas generator in the receiving portion 20. Pressing of the gas bag 1 is effected substantially vertically to the main plane of extension of the prefolded gas bag, wherein in particular a correspondingly configured pressing device (not shown) is used.

[0028] After the pressing operation a gas generator 3 is introduced into the introduction opening 21 and the gas bag 1 is folded into its final dimension by the section 112 of the first portion 11 and the second portion 12 of the gas bag 1 being folded onto each other; for example along a folding line adjoining the roll-folded second portion 12. Thus, the entire second section 112 of the first portion 11 substantially comes to abut against the roll-folded portion 12, wherein the first section 113 with the gas generator 3 laterally adjoins the roll-folded portion 12. This condition of the gas bag 1 folded to the final dimension is shown in FIG. 3 (FIG. 6).

[0029] After being folded to its final dimension, the gas bag 1 can be provided with a fixing element in the form of a fixing strap 4 in order to fix the convolution of the gas bag 1.

[0030] It should be noted that the invention is of course not limited to a particular kind of prefolding. Pressing of the gas bag in principle can be effected at any time of the folding process, i.e. with a gas bag present in basically any prefolding condition. It is also quite conceivable that the entire prefolded gas bag 1 (including the section 113) is pressed. In any case, however, the gas bag 1 only is brought to the final dimension by a folding operation carried out after pressing.