A HELMET FOR IMPACT PROTECTION

Abstract

A helmet for protecting a wearer's head has a protective layer configured to, when the helmet is impacted by a force, absorb the normal component thereof by compression and rupture when the tangential component of the force exceeds a predefined threshold.

Claims

1.-15. (canceled)

16. A helmet for protecting a wearer's head comprising: a protective layer configured to, when the helmet is impacted by a force, absorb the normal component thereof by compression and rupture when the tangential component of the force exceeds a predefined threshold.

17. The helmet according to claim 16 wherein the protective layer comprises closed-cell foam configured to perform said absorbing and said rupturing.

18. The helmet according to claim 17 wherein the closed-cell foam comprises expanded beads.

19. The helmet according to claim 16, wherein the protective layer comprises: a first layer; and protuberances extending from the first layer; and wherein the protuberances are configured to rupture from the first layer when exceeding the predefined threshold.

20. The helmet according to claim 19, wherein the protective layer further comprises: a second layer covering the protuberances.

21. The helmet according to claim 20, wherein the second layer also comprises protuberances configured to rupture from the second layer when exceeding the predefined threshold.

22. The helmet according to claim 21 wherein the protuberances of the first layer and the protuberances of the second layer face towards each other.

23. The helmet according to claim 20 wherein the first and second layer are connected with each other by the protuberances.

24. The helmet according to claim 22 wherein the protuberances of the first layer are interlinked with the protuberances of the second layer.

25. The helmet according to claim 20, wherein the protuberances comprise at least one of the group of: a tubular protuberance; a beam-shaped protuberance; a conical protuberance with an elliptic or polygonal base.

26. The helmet according to claim 18, wherein the protective layer comprises a mixture of the beads and second granules.

27. The helmet according to claim 26 wherein the protective layer is further arranged such that the rupturing initiates at a border between the beads and the granules.

28. The helmet according to claim 26 wherein the beads and granules have a diameter of around 0.5 mm to around 5 mm.

29. The helmet according to claim 26, wherein the beads have a first density between 50 and 70 m.sup.−3.Math.kg; and the granules correspond to second beads having a second density between 90 and 110 m.sup.−3.Math.kg.

30. The helmet according to claim 26, wherein the mixture comprises between 25 and 75 weight percent of the beads with the first density.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Some example embodiments will now be described with reference to the accompanying drawings.

[0057] FIG. 1A illustrates a helmet according to an illustrative embodiment of the invention; and

[0058] FIG. 1B illustrates the helmet of FIG. 1A with a cross-sectional view; and

[0059] FIG. 2A illustrates a protective layer according to a first illustrative embodiment of the invention comprising a first and second layer and protuberances; and

[0060] FIG. 2B illustrates the protective layer of FIG. 2B comprising ruptured protuberances; and

[0061] FIG. 3A illustrates a protective layer according to a second illustrative embodiment of the invention comprising a first and second layer and protuberances; and

[0062] FIG. 3B illustrates a protective layer similar to the illustrative embodiment of FIG. 3A comprising protuberances that are reversely oriented; and

[0063] FIG. 4A illustrates a protective layer according to a third illustrative embodiment of the invention comprising a first and second layer and protuberances; and

[0064] FIG. 4B illustrates a protective layer according to a fourth illustrative embodiment of the invention comprising a first and second layer and protuberances; and

[0065] FIG. 5A illustrates a protective layer according to a fifth illustrative embodiment of the invention comprising a first layer and protuberances; and

[0066] FIG. 5B illustrates the protective layer of FIG. 5A comprising ruptured protuberances; and

[0067] FIG. 6 illustrates a protective layer according to a sixth illustrative embodiment of the invention.

DETAILED DESCRIPTION OF EMBODIMENT(S)

[0068] FIG. 1A illustrates a helmet according to an illustrative embodiment of the invention and FIG. 1B illustrates the same helmet with a cross-sectional view. The helmet 100 is suitable to be worn during sporting activities like, for example, cycling or skiing. When the helmet 100 is worn, the wearer's head is in the position 107.

[0069] The helmet 100 may comprise a clasp or buckle 110 which can be wrapped around the wearer's chin when worn to secure a safe wearing of the helmet 100 on the head during activities. The helmet 100 may further comprise an outer shell 101, and ventilation holes 111. The outer shell 101 may function as a protective layer against external conditions, such as wind or rain, and the ventilation holes may function to manage a heat regulation of the wearer's head, and/or for reasons of aerodynamics, and/or aesthetics. It should be further understood that these functionalities 110 and 111 are illustrative and may vary on the type of activity for which the helmet is designed for, or even may be absent.

[0070] The helmet 100 comprises a protective layer 106, which is illustrated in the cross-sectional view 120 in FIG. 1B. The protective layer 106 has a curved surface 112 on the outside and it may further be covered by the outer shell 101. Alternatively, the curved surface 112 of the protective layer 106 may itself comprise the outer layer of the helmet 100, meaning that there is no outer shell 101.

[0071] During activities, the helmet 100 may be impacted by a force, illustrated by the impacted force 105. This force may, for example, originate from a fall on the ground, or from a hit by an object. The magnitude and direction of the impacted force 105 is a prior not known but may be presented by a vector 105 comprising a normal component 102 and a tangential component 103. The vector 105 further points to point 104 which represents the point of impact. It should be however further understood that the point of impact may also comprise an area or zone of impact depending on the surface whereupon the wearer of the helmet 100 falls, or the shape and size of the object that hits the helmet 100.

[0072] The impacted force 105 is further illustrated in FIG. 2A that illustrates the protective layer 106 comprising a first or outer layer 200 and a second or inner layer 201. The protective layer 106 in this first illustrative embodiment further comprises protuberances 202 extending from both layers 200 and 201 and connecting the layers 200 and 201 with each other.

[0073] The force 105 impacts the protective layer 106 at the outside therefrom thus at the curved surface 112, and the tangential component 103 thereof is transferred to the other zones of the protective layer 106. Likewise, the normal component 102 is transferred as well to the other zones of the protective layer 106.

[0074] Alternatively, when the helmet 100 comprises an outer shell 101, the impacted force 105 first impacts the outer shell 101, and the force 105 is subsequently transferred to the protective layer 106.

[0075] The normal component 102 is absorbed by the protective layer 106 through compression. In other words, the protective layer 106 compresses such that the outer layer 200, the protuberances 202 and the inner layer 201 come closer together during compression, and afterwards, when the impacted force 105 is no longer present, the layers 200 and 201 and protuberances 202 may return to their initial shape, or may be deformed plastically, depending on the magnitude of the normal component 102 with respect to the modulus of elasticity of the protective layer 106, yet without breaking or rupturing.

[0076] The tangential component 103 is transferred to the body of the protective layer 106, which is illustrated by arrow 210. Arrow 210 thus illustrates that, due to the tangential component 103 of the impacted force 105, that a relative movement of the outer layer 200 with respect to the protuberances 202 and/or the inner layer 201 occurs.

[0077] When the tangential component 103 exceeds a predefined threshold, the protuberances 202 of the protective layer 106 are configured to rupture. The rupturing is thus initiated by the tangential component 103 of the impacted force 105 and depends on the angle under which the impacted force 105 hits 104 the protective layer 106 and the magnitude thereof.

[0078] The rupturing of the protuberances 202 is illustrated by ruptures 211 and rupture 212. The protuberances 202 in this first illustrative embodiment comprises tubular or beam-shaped protuberances. Because of this the strength characteristics of the protuberances remain equal over their respective longitudinal direction. This means that the protuberances will rupture at a spot where its cross-section is no longer resistant to the predefined threshold. This may, for example, be at the middle of a protuberances, as illustrated by ruptures 211, or at an extremity as illustrated by rupture 212. The position will thus be determined by the location 104 of the impacted force 105 and the way it is transferred 210 to the protuberances 202. Depending on the magnitude and direction of the impacted force 105, a rupturing may also occur at the layer 200, as illustrated by rupture 213.

[0079] As a result of the rupturing, the outer layer 200 is detached 203 from the inner layer 201. It may further occur that only a part of the protuberances is ruptured. In other words, the rotational impact or acceleration originating from the impacted force 105 and more in particular the tangential component 103 thereof is then absorbed by the rupturing of a part of the protuberances, while other protuberances remain intact.

[0080] The protuberances may also comprise other shapes compared to a tubular or beam-shapes. In FIG. 3A and FIG. 3B a second illustrative embodiment of the invention is illustrated comprising conical protuberances 300 such as cone 302. It should be further understood that a cone is a three-dimensional geometric shape tapering smoothly from a base to an apex, wherein the base and the apex may be circular, but may also comprises any other polygonal shape. The protuberances 300 may thus also for example comprise pyramids.

[0081] The conical protuberances 300 are connected to the outer layer 200 by their respective apex, as illustrated by apex 311, and by their respective base to the inner layer 201, such as base 310. The configuration may also be reverse, this is the bases are connected to the outer layer 200 and the apexes to the inner layer 201, as illustrated by protuberances 301 of FIG. 3B.

[0082] Due to the tapered configuration of the protuberances 300 and 301, the strength characteristics vary because of the varying cross-sections. For example, when the tangential component 103 is transferred, stresses originating therefrom may be concentrated at the apex of the conical protuberances, such that the rupturing is initiated at these apexes. This is illustrated by rupture 312 at the outer layer 200, and by rupture 313 at the inner layer 201. Depending on the magnitude and direction of the impacted force 105, a rupturing may also occur at the outer layer 200, as illustrated by rupture 314.

[0083] Besides a uniform directional arrangement of the conical protuberances, such as configuration 300 where the bases are all located at the inner layer 201, or configuration 301 where all the apexes are located at the inner layer 201, the conical protuberances may also be arranged in an alternating pattern as illustrated in FIG. 4A by protuberances 400. In this third illustrative embodiment, the direction of the tapered configuration may be altered, and the embodiment may further comprise beam-shaped and/or tubular protuberances. In other words, the pattern of the protuberances may be adapted such that it comprises a variety of shapes, cross-sections and/or arrangement.

[0084] A part of the protuberances 400 may also extend from the outer layer 200, while the other part extends from the inner layer 201, whereby the outer 200 and inner 201 layer are connected to each other by the protuberances. The protuberances of both layers 200 and 201 may also be interlinked as illustrated in FIG. 4B by a fourth illustrative embodiment of the protective layer 106. The protuberances 401 are shaped in such a way that they interlink or clasp with opposite protuberances. For example, protuberance 403 extending from the outer layer 200 clasps with protuberance 402 extending from the inner layer 201. As a result, a pattern of interlinked protuberances 401 together with the inner 201 and outer 200 layer forms the protective layer 106.

[0085] According to a fifth illustrative embodiment, the protective layer 106 may comprise one layer with protuberances extending therefrom, as illustrated in FIG. 5A and FIG. 5B. The layer 500 from where the protuberances 502 extend may be the outer layer of the helmet 100, or may be the inner layer, thus where the wearer's head 107 is located when worn.

[0086] The impacted force 105 is then either transferred 503 to the protuberances 502, or the protuberances 502 are directly impacted by the force. The protuberances 502 are likewise configured to rupture when the tangential component 103 of the impacted force 105 exceeds the predefined threshold. This is illustrated by ruptures 510 in FIG. 5B.

[0087] The protective layer 106 may also, according to a sixth embodiment, comprise one whole shape 600, for example, an in-mold expanded polystyrene comprising expanded beads and granules 602. The granules 602 are arranged such that the rupturing, when the tangential component 103 exceeds the predefined threshold, is initiated at the borders of the granules 602. The rupturing may then result in a rupture 601 over a whole length of the protective layer 106.

[0088] The protective layer as illustrated in FIG. 6A may also comprises one whole shape without the granules 602 but comprising a mixture of beads with different densities. For example, a first mixture of beads with a density between 50 and 70 m.sup.−3.Math.kg, preferably 60 m.sup.−3.Math.kg, and a second mixture of beads having a density between 90 and 110 m.sup.−3.Math.kg, preferably 100 m.sup.−3.Math.kg. Both mixtures may then equally be divided, thus each 50 weight percent, or the first mixture may have between 25 and 75 weight percent, whereas consequently the second mixture has a weight percentage determined by that of the first mixture.

[0089] Although the present invention has been illustrated by reference to specific embodiments, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied with various changes and modifications without departing from the scope thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. In other words, it is contemplated to cover any and all modifications, variations or equivalents that fall within the scope of the basic underlying principles and whose essential attributes are claimed in this patent application. It will furthermore be understood by the reader of this patent application that the words “comprising” or “comprise” do not exclude other elements or steps, that the words “a” or “an” do not exclude a plurality, and that a single element, such as a computer system, a processor, or another integrated unit may fulfil the functions of several means recited in the claims. Any reference signs in the claims shall not be construed as limiting the respective claims concerned. The terms “first”, “second”, third”, “a”, “b”, “c”, and the like, when used in the description or in the claims are introduced to distinguish between similar elements or steps and are not necessarily describing a sequential or chronological order. Similarly, the terms “top”, “bottom”, “over”, “under”, and the like are introduced for descriptive purposes and not necessarily to denote relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances and embodiments of the invention are capable of operating according to the present invention in other sequences, or in orientations different from the one(s) described or illustrated above.