AIRBAG-HELMET AND AIRBAG ADAPTED FOR BEING USED AS A PART OF SUCH AN AIRBAG-HELMET

Abstract

An airbag-helmet having a protective main body (10) having an inner surface pointing towards the head of the user when the helmet is worn, and an outer surface pointing away from the head of the user when the helmet is worn. Further, an inflator (40) and an airbag (30) being attached to the protective main body (10) at least indirectly and being in fluid communication to the inflator (40) are provided. The airbag (30) includes at least one tubular protection section (30a, 30b, 30c) extending from the outer surface of the protective main body (10) when the airbag (30) is filled with gas by the inflator (40).

Claims

1. An airbag-helmet comprising: a protective main body having an inner surface facing towards the head of the user when the helmet is worn, and an outer surface facing away from the head of the user when the helmet is worn, an inflator and an airbag attached to the protective main body at least indirectly and being in fluid communication with the inflator, said airbag comprising at least one tubular protection section, the tubular protection section extending from the outer surface of the protective main body when the airbag is filled with gas by the inflator.

2. The airbag-helmet according to claim 1, further comprising at least two, tubular protection sections.

3. The airbag-helmet according to claim 2, further comprising all the tubular protection sections are filled by the same inflator.

4. The airbag-helmet according to claim 1, further comprising in that the tubular protection section(s) extend substantially in the longitudinal direction of the airbag-helmet.

5. The airbag-helmet according to claim 4, further comprising wherein three of the tubular protection sections are provided, the three tubular protection sections forming a T.

6. The airbag-helmet according to claim 1, further comprising the protective main body consists of one of a rigid foamed material, a foamed plastic material, and an expanded polystyrene.

7. The airbag-helmet according to claim 1, further comprising the minimum thickness of the protective main body between the inner surface and the outer surface is at least 5 mm.

8. The airbag-helmet according to claim 1, wherein the protective main body comprises through-openings extending from the outer surface to the inner surface.

9. The airbag-helmet according to claim 1, further comprising the protective main body has a groove at the outer surface of the protective main body, wherein at least a part of the un-deployed airbag is located inside the groove, wherein the groove has a depth between 1 and 10 mm.

10. The airbag-helmet according to claim 1, further comprising an actuation mechanism triggering the inflator or opening a passageway between the inflator and the airbag, the actuation mechanism comprising an acceleration sensor.

11. The airbag-helmet according to claim 1, further comprising the airbag is attached to the protective main body at least two attachment means being remote from each other, wherein each of the tubular protection section is attached to the protective main body via a plurality of attachment points.

12. The airbag-helmet according to claim 1 wherein the airbag comprises a flexible, inelastic airbag a woven plastic material.

13. The airbag-helmet according to claim 12, wherein the airbag comprises two layers of the flexible, inelastic airbag material which are connected to one another.

14. The airbag-helmet according to claim 13, further comprising in that two layers of flexible, inelastic airbag material are provided.

15. The airbag-helmet according to claim 12, wherein the airbag further comprises a coating covering at least a section of the flexible, inelastic airbag material.

16. The airbag-helmet according to claim 1, further comprising in that each tubular protection section has a cross-section between 5 and 60 cm.sup.2 when fully deployed.

17. The airbag-helmet according to claim 1, further comprising in that each tubular protection section has a length between 30 and 45 cm.

18. The airbag-helmet according to claim 1, further comprising in that the at least one of the tubular protection section extend at least 5 mm, preferably at least 10 mm from the outer surface of the protective main body, when the airbag is deployed.

19. The airbag according to claim 1, adapted for being used as a part of the airbag helmet.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0030] FIG. 1 a schematic plan view onto a main body of a first embodiment of the inventive airbag-helmet,

[0031] FIG. 1a a sectional view taken along plane A-A in FIG. 1,

[0032] FIG. 1b a sectional view taken along plane B-B in FIG. 1,

[0033] FIG. 1c a sectional view taken along plane C-C in FIG. 1,

[0034] FIG. 2 a cover being adapted for being attached to the protective main body of FIG. 1 in a plan view according to FIG. 1,

[0035] FIG. 2a a sectional view taken along plane D-D in FIG. 2,

[0036] FIG. 3 the protective main body shown in FIG. 1 after attaching an airbag device to it,

[0037] FIG. 3a a sectional view taken along plane E-E in FIG. 3,

[0038] FIG. 4 the items shown in FIG. 3a and the cover of FIG. 2a being attached to the protective main body, such that a bicycle helmet according to a first embodiment of the invention is formed,

[0039] FIG. 5 the airbag-helmet of FIG. 4 after the airbag has been filled with gas such that it is in its deployed state,

[0040] FIG. 6 what is shown in FIG. 5 in a sectional representation according to FIG. 1c,

[0041] FIG. 7 a second embodiment in a representation according to FIG. 3,

[0042] FIG. 8 a third embodiment of the invention in a representation according to FIG. 4,

[0043] FIG. 9 two cuttings of an airbag,

[0044] FIG. 10 the airbag being sewn from the cuttings shown in FIG. 9, and

[0045] FIG. 11 a variation to the first cutting of FIG. 9.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0046] FIGS. 1 to 1c show a protective main body. This protective main body 10 has the typical half shell-shape of a protective main body of a bicycle helmet. This protective main body 10 has a substantially concave inner surface 11 and a substantially convex outer surface 12. The minimum distance of the inner surface 11 and the outer surface 12 is typically at least five millimeters, but can be substantially larger. The protective main body 10 is usually made of a lightweight foamed plastic material, like expanded polystyrene (EPS). As is known in the prior art, through openings 16 can extend through the protective main body.

[0047] According to the shown embodiment of the invention, the outer surface 12 of the protective main body 10 shows a groove 14. This groove 14 has a central section 14a extending in the longitudinal direction of the helmet along a substantial length of the helmet, two lateral sections 14b, 14c extending from the front end of the central section 14a, and an inflator section 14d extending from the rear end of central section 14a.

[0048] The central section 14a and the lateral sections 14b, 14c typically have a depth of several millimeters, wherein the depth is far less than the thickness of the protective main body 10. The depth of the inflator section 14d usually exceeds the depth of the central section and the lateral sections.

[0049] FIGS. 2 and 2a show a cover 20 being adapted for being attached to the outer surface 12 of the protective main body 10. This cover 20 is substantially thinner than the protective main body 10 and typically consists of a non-foamed plastic material like polypropylene, polycarbonate or acrylonitrile butadiene styrene (ABS). This cover is of course also of a concave-convex shape and the inner surface 21 of the cover 20 conforms (except the grooves) to the outer surface of the protective main body 10. In the embodiment shown the cover 20 comprises a breaking line 23 which divides the cover 20 into an upper part 24 and an annular lower part 25. As for the protective main body 10, through openings 26 extend through the cover 20. These through openings 26 are basically congruent with the through openings 16 in the protective main body 10.

[0050] FIG. 3 shows the protective main body 10 shown in FIG. 1 and an airbag device attached to it. This airbag device comprises an airbag 30, an inflator 40 and an actuation mechanism 42. The airbag has three tubular protection sections 30a to 30c which extend essentially in a longitudinal direction DL from a rear end area of the protective main body 10 to a front end area of the protective main body 10. These three tubular protection sections 30a to 30c form a T whose junction is located at the front end area of the protective main body 10, such that the airbag 30 comprises a middle tubular protection section 30a, a right tubular protection section 30b and a left tubular protection section 30c. The airbag 30 is filled from the rear end of the middle tubular protection section 30a. The airbag 30 is folded into the central section 14a and the lateral sections 14b, 14c of the groove 14.

[0051] The inflator 40 is located in the inflator section of the groove 14 and is attached to the protective main body 10 as well as to the airbag 30 at least indirectly. This inflator 40 can be any type of known inflator, especially a pyrotechnic gas generator or an inflator comprising compressed gas.

[0052] The actuation mechanism 42 actuates the inflator and/or opens a fluid conduit between the inflator 40 and the airbag 30. In case that the inflator 40 is a pyrotechnic gas generator, the actuation mechanism 42 usually needs a battery or another electrical storage means such that it can ignite a pyrotechnic load of the inflator. In case that the inflator contains compressed gas, the actuation mechanism 42 might only need a valve. The latter case is schematically shown in FIG. 2 as an example, but is of course not limiting. Further, the actuation mechanism 42 comprises an acceleration sensor (also called inertia sensor) like it is known from automotive airbag devices. This acceleration sensor can work purely mechanical, especially with an inertia mass, or electronically, as is also known in the art.

[0053] FIG. 4 shows what is shown in FIG. 3a after the cover 20 has been attached to the protective main body 10; thus the complete bicycle helmet is shown. Usually an adhesive is used for attachment purposes. In order to allow an unhindered deployment of the airbag 13, the cover 20 is attached to the protective main body only via the lower part 25 of the cover 20 (between the breaking line 23 and the edge). Straps that extend from the protective main body for securing the helmet to the user's head are not shown in this representation.

[0054] FIGS. 5 and 6 show the situation after deployment of the airbag 30. One sees, that the tubular protection sections 30a to 30c extend from the outer surface 12 of the protective main body 10 such that in the typical case that the airbag-helmet hits a essentially flat surface, this surface is first hit by the airbag 30. At the rear end, the airbag 30 is attached to the protective main body 10 via the inflator 40. Since one attachment point is usually not sufficient, at least one additional attachment is provided, here at the front region of the helmet. In the shown example, an attachment tether 32 is provided for this purpose. Of course it would also be possible to attach the airbag 30 directly to the protective main body 10. An example of an airbag having several attachment points will be described later.

[0055] The deployed tubular protection section usually has a cross-section of between 5 and 60 cm.sup.2 and a length of between 30 and 45 cm.

[0056] FIG. 7 shows an alternative embodiment. The main difference to the embodiment just described is that the junction of the T of the airbag 30 is located at the rear end, such that all tubular protection sections 30a to 30b are filled from the rear. In this case at least each front end of a tubular protection section should be connected to the protective main body 10.

[0057] Instead of providing the protective main body 10 with grooves in order to create an accommodation for the airbag 30, it is also possible to provide at least one groove in the cover 20 for this purpose. An embodiment with such a cover-side groove 29 is shown in FIG. 8. Since the cover material is usually rather thin, the cover shows protruding regions 28 whose inner sides form the cover-side grooves 29.

[0058] It would also be possible that the accommodation for the airbag has at least one body-side groove and at least one cover-side groove opposite the body-side groove.

[0059] In all shown embodiments, and this is typical for the airbag-helmet according to the invention, the total area of the used airbag material is small. This leads to a little need of storage space. Also, the space to be filled with gas is small, such that only a small and thus lightweight inflator is needed.

[0060] FIG. 9 shows two cuttings 34, 36 from which an airbag as schematically shown in FIG. 2 can be assembled such that each of those cuttings 34, 36 forms a layer of the airbag 30. The two cuttings are congruent and can consist of a woven plastic material. Each cutting typically has an area between 500 and 1200 cm.sup.2. The cuttings usually consist of or comprise a basic material, for example a woven plastic material. This basic material is substantially inelastic and is also referred to as flexible, inelastic airbag material. The two cuttings 34, 36 can be assembled to the airbag 30 by applying a single connection for example a connecting seam 38 (FIG. 10). The airbag shown in FIG. 5 can of course be made in the same type of manufacturing process.

[0061] In contrast to a classic airbag being installed inside a vehicle, it is likely that the deployed airbag hits a rather rough surface. So, it can be preferred to provide a resistant coating or covering of the airbag, for example a protective textile layer which covers at least a part of the outer surface of the basic material, such that the airbag consists ofusually wovenbasic material and the coating or covering layer. The coating itself might have elastic properties, but the airbag as a whole remains substantially inelastic.

[0062] As is shown in FIG. 11, at least one of the layers could comprise mounting ears 34a, such that the airbag can easily be attached to the basic body (for example by means of gluing) at a plurality of positions. This has the advantage that the deployed airbag is securely held in position in all conceivable accident scenarios. Another advantage is that such a plurality of mounting ears can help to shape the deployed tubular protection sections to have substantially oval cross-sections like shown in FIG. 5, instead of a substantially circular cross sections which they would have without additional measures. An oval cross-section has the advantage that the covered surface is enlarged without the need of increasing the volume of the airbag to be filled with gas.

LIST OF REFERENCE NUMBERS

[0063] 10 protective main body [0064] 10a rear end [0065] 10b front end [0066] 11 inner surface [0067] 12 outer surface [0068] 14 groove [0069] 14a central section [0070] 14b, 14c lateral section [0071] 14d inflator section [0072] 16 through opening [0073] 20 cover [0074] 21 inner surface [0075] 22 outer surface [0076] 23 breaking line [0077] 24 upper part of cover [0078] 25 lower part of cover [0079] 26 through opening [0080] 28 protruding region [0081] 29 cover-side groove [0082] 30 airbag [0083] 30a-30c tubular protection section [0084] 32 attachment tether [0085] 34 first cutting of airbag forming first layer of airbag [0086] 34a attachment ear [0087] 36 second cutting of airbag forming second layer of airbag [0088] 38 connecting seam [0089] 40 inflator [0090] 42 actuation mechanism