Helmet with sliding facilitator

(12) Patent Specification do) SE 534 868 C2

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Sweden (21) Patent application number: 1050458-7 (45) Patent granted: 2012-01-24 (41) Application generally available: 2011-11-08 (22) Patent application submitted: 2010-05-07 (24) Maturity date: 2010- 05-07 (83) Deposit of microorganism: - (30) Priority information: - (51) International class:

A42B3 / 06 (2006.01)

A42B3 / 10 (2006.01)

A42B 3/12 (2006.01)

<td>(73) Patent holders:</td><td>Mips AB, Birger Jarlsgatan 34, 114 29 Stockholm SE</td>

<td>(72) Inventor:</td><td>Peter Halldin, Enskede SE</td>

<td>(74) Agents:</td><td>Bergenstråhle &amp; Lindvall AB, Box 17704,118 93 Stockholm SE</td>

<td>(54) Name:</td><td>Helmet with sliding promoter provided at an energy absorbing bearing</td>

<td>(56) Publications cited:</td><td>SE 518223 C2</td>

(47) Summary:

Helmet including an energy-absorbing bearing (2), a fastener (3) intended to attach the helmet to a user's head, and a sliding promoter (5).

The sliding promoter (5) is located on the inside of the energy absorbing layer (2) and is attached to the fastening device (3) and / or to the inside of the energy absorbing layer (2) to create a slidable between the energy absorbing layer (2) and the fastening device (3). ).

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534 868

SUMMARY

Helmet including an energy-absorbing bearing (2), a fastener (3) intended to attach the helmet to a user's head, and a sliding promoter (5). The sliding promoter (5) is located on the inside of the energy absorbing layer (2) and is attached to the fastening device (3) and / or to the inside of the energy absorbing layer (2) to create a slidable between the energy absorbing layer (2) and the fastening device (3). ).

534 868

HELMET WITH SLIDING PROMOTOR PROVIDED BY AN ENERGY-ABSORBING LAYER

TECHNICAL FIELD The present invention relates to a helmet comprising an energy absorbing layer, with or without an outer shell, and a sliding promoter provided on the inside of the energy absorbing layer.

Background To prevent or reduce skull and brain damage, many activities require a helmet. Most helmets include a hard outer shell, often made of plastic or a composite material, and an energy-absorbing layer called a liner. Nowadays, a protective helmet must be designed to meet certain legal requirements that, among other things, result from the maximum acceleration that can occur in the brain's center of gravity at a certain load. Usually, tests are performed where a so-called dummy skull fitted with a helmet is subjected to a radial blow to the head. This has resulted in modern helmets having a good energy absorption at impact radially directed towards the skull, while the energy absorption for other load directions is not optimized.

In a radially directed stroke, the head will be accelerated in a translational movement resulting in a linear acceleration. The translation movement can result in fractures of the skull and / or pressure or abrasion damage to the brain tissue. According to injury statistics, however, pure radial blows are unusual.

On the other hand, a purely tangential impact resulting in a pure angular acceleration on the head is also uncommon.

The most common type of impact is oblique impact, which is a combination of a radiusil and a tangential force acting simultaneously on the head. The oblique impact results in both translational acceleration and rotational acceleration of

534 868 brain. Rotational acceleration causes a rotation of the brain within the skull, which causes damage to bodily elements that connect the brain with the skull and also to the brain itself.

Examples of rotational injuries are, on the one hand, subdural haematoma SH, bleeding as a consequence of blood vessels rupturing, and, on the other, diffuse axonal damage, DAI, which can be assembled as nerve fibers overstretched as a consequence of large shear deformation in the brain tissue. Depending on the rotational force, such as duration, amplitude and degree of increase, either SH or DAI occurs, or a combination of these occurs. Overall, SH occurs in cases of short duration and high amplitude, while DAI occurs at longer durations and more scattered acceleration loads. It is important that these phenomena are taken into account in order to provide good protection for the skull and brain.

The head has a natural protection system that attempts to dampen these forces by using the scalp, hard skull and cerebrospinal fluid beneath it. During an impact, the scalp and cerebrospinal fluid act as a rotational shock absorber by both compressing and sliding over the skull. Most helmets of today do not provide protection against rotational injuries.

Important details of, for example, bicycle, riding and ski helmets are that they are well ventilated and have an aerodynamic shape. Modern bicycle helmets are usually of the type of injection molded so-called shell molds made by inserting a thin, rigid shell during the casting process. This technology allows for more complex shapes than hard shell helmets and also allows for the creation of larger ventilation holes.

Summary A helmet comprising an energy absorbing layer and a sliding promoter on the inside of the energy absorbing layer is described.

534 868 The helmet includes a fastener for attaching the helmet to a user's head. The sliding promoter may be attached to the fastener or to the inside of the energy absorbing layer to create slidability between the energy absorbing layer and the fastener.

Preferably, an outer shell is provided on the outside of the energy absorbing layer. A helmet designed in this way can be manufactured using in-mold technology, although it is possible to use the idea shown in all types of helmets.

In a further embodiment, the fastener is attached to the energy absorbing layer and / or to the outer shell by at least one fastener, which may be arranged to absorb energy and forces through an elastic, semi-elastic or plastic deformation. During an impact, the energy-absorbing layer acts as an energy absorber by compressing the energy-absorbing layer and if an outer shell is used it will distribute the impact energy over the shell. The sliding promoter will allow sliding between the fastener and the energy-absorbing layer, which provides a controllable way of absorbing the rotational energy that is otherwise transmitted to the brain. Rotational energy can be absorbed by frictional heat, deformation of the energy absorbing layer or deformation or displacement of the at least one fastener. The absorbed rotational energy will reduce the amount of rotational acceleration affecting the brain and thus reduce the rotation of the brain within the skull.

The fastener may comprise at least one suspension member having a first and a second portion. The first portion of the suspension means may be adapted to be attached to the energy absorbing layer and the second portion of the suspension means may be adapted to be attached to the fastener.

534 868

The sliding promoter gives the helmet a Function (slidability) and can be arranged in many different ways. For example, it may be a low friction material disposed on or integrated with the fastener on its surface facing the energy absorbing layer and / or disposed on or integrated with the inside surface of the energy absorbing layer facing the fastener.

The sliding promoter provides the possibility of sliding motion in all directions. It is not limited to movements around a particular axis.

Note that all embodiments or parts of embodiments as well as all methods or parts of methods can be combined in all different ways.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described, by way of example, with reference to the accompanying drawings, in which:

Fig. 1 shows a helmet, according to one embodiment, in a sectional view; Fig. 2 shows a helmet, according to one embodiment, in a sectional view, when placed on a user's head; Fig. 3 shows a helmet placed on a user's head during a front impact, Fig. 4 shows the helmet placed on a user's head under a front impact, Fig. 5 shows a detail view of a fastener, Fig. 6 shows an alternative embodiment of a fastener; Fig. 7 shows an alternative embodiment of a fastener;

534 Fig. 8 shows an alternative embodiment of a fastener, Fig. 9 shows an alternative embodiment of a fastener, Fig. 10 shows an alternative embodiment of a fastener, Fig. 1 1 shows an alternative embodiment of a fastener, Fig. 12 shows an alternative embodiment of a fastener, Fig. 13 shows an alternative embodiment of a fastener, Fig. 14 shows an alternative embodiment of a fastener. FIG. 15 shows an alternative embodiment of a fastener, Fig. 16 shows a test result table, Fig. 17 shows a test result graph, and Fig. 18 shows a test result graph.

DESCRIPTION OF EMBODIMENTS In the following, a detailed description of embodiments will be given. It should be understood that the figures are for illustration only and thus do not limit the scope in any way. Sold, references to directions such as up or down refer only to directions shown in the figures.

One embodiment of a protective helmet comprises an energy absorbing layer and a sliding promoter provided on the inside of the energy absorbing layer. In one embodiment, an in-mold helmet is intended for cycling. The helmet includes an outer preferably thin, rigid shell made of polymeric materials such as polycarbonate, ABS, PVC, fiberglass, Aramid, Twaron, carbon fiber or Kevlar. It is also possible to omit the outer shell. On the inside of the shell is arranged one

534 868 energy absorbing layers which may be a polymer foam material such as EPS (expanded polystyrene) or other structures such as, for example, honeycomb. A sliding promoter is provided on the inside of the energy-absorbing layer and is arranged to slide against the energy-absorbing layer or to a fastener intended to attach the helmet to a user's head. The fastener is attached to the energy absorbing layer and / or to the shell by means of fasteners intended to absorb impact energy and forces.

The sliding promoter may be a material having a low coefficient of friction or may be coated with a low friction material: Examples of possible materials are PTFE, ABS, PVC, PC, fabric material. Furthermore, it is conceivable that sliding is made possible by the structure of the material, for example a material having a fiber structure so that the fibers can slide against each other.

During an impact, the energy absorbing layer acts as an energy absorber by compressing the energy absorbing layer and if an outer shell is used it will distribute the impact energy over the shell. The sliding promoter will allow sliding between the fastener and the energy-absorbing layer, which provides a controllable way of absorbing the rotational energy that is otherwise transmitted to the brain. Rotational energy can be absorbed by frictional heat, deformation of the energy absorbing layer or deformation or displacement of the at least one fastener. The absorbed rotational energy will reduce the amount of rotational acceleration affecting the brain and thus reduce the rotation of the brain within the skull. The risk of rotational damage such as subdural haematoma, SH, blood vessel rupture and DAI is therefore reduced.

Fig. 1 shows a helmet according to an embodiment in which the helmet comprises an energy absorbing layer 2. The outer surface 1 of the energy absorbing layer 2 may be of the same material as the energy absorbing layer 2 or it is

534 868 it is possible that the outer surface 1 is a rigid shell 1 made of a material other than the energy-absorbing layer 2. A sliding promoter 5 is located on the inside of the energy-absorbing layer 2 in relation to a fastening device 3 for attaching the helmet to a user's head. According to the embodiment shown in FIG. 1 For example, the sliding promoter 5 is attached to or integrated into the energy absorbing layer 2, but it is equally conceivable that the sliding promoter 5 is arranged on or integrated with the fastener 3, for the same reason that is to provide a slidability between the energy absorber layer 2 and the fastener 3. The helmet of Fig. 1 has a plurality of air holes 17 which allow air flow through the helmet.

The fastener 3 is attached to the energy absorbing layer 2 and / or the outer shell 1 by means of four fasteners 4a, 4b, 4c, 4d intended to absorb energy through an elastic, semi-elastic or plastic deformation. Energy can also be absorbed through friction which creates heat and / or deformation of the fastener, or any other part of the helmet. In the embodiment shown in Figure 1, the four fasteners 4a, 4b, 4c and 4d are suspension means 4a, 4b, 4c, 4d, which have a first and a second portion 8, 9, the first portion 8 of the suspension means 4a, 4b, 4c , 4d is intended to be attached to the fastener 3, and the second portion 9 of the suspension means 4a, 4b, 4c, 4d is intended to be attached to the energy absorbing layer 2.

The sliding promoter 5 may be a low friction material which, in the illustrated embodiment, is arranged on the outside of the fastener 3 facing the energy absorbing layer 2, but in other embodiments it is equally possible that the sliding promoter is arranged on the inside of the energy absorbing layer 2. a wax polymer such as PTFE, PFA, FEP, PE and UHMWPE, or a powder material which may be permeated by a lubricant. This low friction material can be applied to either one or both of sliding promoters and the energy absorbing layer, in some embodiments, the energy absorbing layer is itself arranged to be a sliding promoter and can be

534 868 include a low friction material. The fastener may be made of an elastic or semi-elastic material such as PC, ABS, PVC or PTFE, or natural fiber material such as cotton fabric. Fig. 1 also shows an adjusting device 6 for adjusting the diameter of the headband for a specific user. In other embodiments, the headband may be an elastic band, in which case the adjusting device 6 may be excluded.

Fig. 2 shows an embodiment of a helmet similar to the helmet of Fig. 1, when placed on the head of a user. But in Fig. 2, the fastener 3 is attached to the energy absorbing layer only by two fasteners 4a, b, designed to absorb energy and forces elastically, semi-elastically or plastically. The embodiment of Fig. 2 includes a hard outer shell 1 made of a material other than the energy absorbing layer 2.

Fig. 3 shows the helmet according to the embodiment of Fig. 2 when it is subjected to a frontal oblique impact stroke which gives a rotational force to the helmet which causes the energy-absorbing layer 2 to slide relative to the fastening device 3. The fastening device 3 is attached to it. energy absorbing layer 2 by means of the fastening means 4a, 4b. The fixation absorbs the rotational forces by deforming elastically or semi-elastically.

Fig. 4 shows the helmet according to the embodiment of Fig. 2 when subjected to a frontal impact stroke I, which creates a rotational force which causes the energy-absorbing layer 2 to slide relative to the fastening device 3.

The fastener 3 is attached to the energy absorbing layer by defective fasteners 4a, 4b which absorb the energy by plastic deformation and thus need to be replaced after impact. A combination of the embodiments of FIG.

and Fig. 4 is very conceivable, ie one part of the fasteners breaks and absorbs the plastic plastically while another part of the fasteners deforms and

534 868 absorbs forces elastically. In combined embodiments, it is conceivable that only the plastic deformable portion must be replaced after impact.

The upper part of FIG. 5 shows the outside of a fastener 3 according to an embodiment in which the fastener comprises a headband 3a, intended to enclose the user's head, a dorsoventral band 3b which extends from the user's forehead to the rear of the user's head and is attached to the headband 3a, and lateral band 3c which extends from the lateral · left side of a user's head to the lateral · right side of a user's head and is attached to the headband 3a. Parts or pieces of the fastener 3 may be provided with sliding promoters. In the illustrated embodiment, the material of the fastening means can act as a sliding promoter. It is also conceivable to provide the fastener 3 with an added low friction material.

Fig. 5 also shows four fasteners 4a, 4b, 4c, 4d fixed to the fastener 3. In other embodiments, the fastener 3 may be only one headband 3a or a whole cap intended to completely cover the upper part of the user's head or any other design that acts as a fastener for mounting on a user's head.

The lower part of Fig. 5 shows the inside of the fastener 3 which has an adjusting device 6 for adjusting the diameter of the headband 3a for the specific user. In other embodiments, the headband 3a may be an elastic headband and then the adjusting device may be excluded.

Fig. 6 shows an alternative embodiment of a fastener 4 in which the first portion 8 of the fastener 4 is attached to the fastener 3, and the second portion 9 of the fastener 4 is attached to the energy absorbing layer 2 by means of an adhesive. The fastener 4 is intended to absorb impact energy and forces by deforming elastically, semi-elastically or plastically.

534 868 Figure 7 shows an alternative embodiment of a fastener 4 in which the first portion 8 of the fastener 4 is attached to the fastener 3, and the second portion 9 of the fastener 4 is secured to the energy absorbing layer 2 by a mechanical fastener 10. which extends into the energy absorbing layer 2.

Fig. 8 shows an alternative embodiment of a fastener 4 in which the first portion 8 of the fastener 4 is attached to the fastener 3, and the second portion 9 of the fastener 4 is secured to the inside of the energy absorbing layer 2, e.g. . by casting the fastener on the inside of the energy absorbing layer

2.

Fig. 9 shows a fastener 4 in a sectional view and an AA view. In this embodiment, the fastener 3 is attached to the energy-absorbing layer 2 by the fastener 4 with a second portion 9 located in a female portion 12 for elastic, semi-elastic or plastic deformation, and a first portion 8 coupled to the fastener 3. The female part 12 includes flanges 13 intended to flex or deform elastically, semi-elastically or plastically when subjected to sufficient tension by the fastening means 4 so that the second portion 9 can leave the female part 12.

Fig. 10 shows an alternative embodiment of a fastener 4 in which the first portion 8 of the fastener 4 is attached to the fastener 3, and the second portion 9 of the fastener 4 is attached to the inside of that shell 1, all the way through it. energy absorbing layer 2. This can be done, for example, by fastening the fastener 4 on the inside of the energy absorbing layer material 2. It is also conceivable to arrange the fastener 4 through a hole in the shell 1 from the outside of the helmet (not shown).

534 868 Fig. 11 shows an embodiment in which the fastener 3 is attached to the energy absorbing layer 2 at its outer edge by a membrane or sealing foam 24, which may be elastic or intended for plastic deformation.

Fig. 12 shows an embodiment in which the fastening device 3 is attached to the energy absorbing layer 2 by means of a mechanical fastening element comprising mechanical engagement means 29, with a self-locking function similar to that of a self-locking cable tie 4.

Fig. 13 shows an embodiment in which the fastener 4 is an interconnecting sandwich layer 27, such as a sandwich fabric, which may comprise elastic, semi-elastic or plastic deformable fibers connecting the fastener 3 with the energy-absorbing layer 2 and is intended to be sheared when shear forces are applied. thus absorbing rotational energy or forces.

Fig. 14 shows an embodiment in which the fastening means comprises a magnetic fastening means 30, which may comprise two magnets with attractive forces, such as hypermagnets, or a part comprising a magnet and a part comprising a magnetic material, such as iron.

Fig. 15 shows an embodiment in which the fastening means is retractable by means of an elastic handle 28 and / or an elastic female part 12 which is removably coupled (so-called snap coupling) so that the handle 28 is detached from the female part 12 when a sufficient deformation affects the helmet, in the event of a blow, and the trade 28 may be reintroduced into the female part 12 to regain its functionality.

In the embodiments shown here, the distance between the energy absorbing layer and the fastener can vary from virtually nothing to a substantial distance without departing from the ppf in the η ni ng concept.

534 Furthermore, in the embodiments shown here, it is also conceivable that the fasteners are hyperelastic, so that the material absorbs energy elastically but at the same time partially deforms plastically without completely falling off.

In the embodiments comprising multiple fasteners, it is also more conceivable that one of the fasteners is a head fastener designed to deform plastically when subjected to sufficient deformation, while the further fasteners are intended to be deformed only elastically.

Fig. 16 is a table obtained from a test performed with a helmet with a sliding promoter (MIPS) compared to a regular helmet (Original) without a sliding layer between the fastener and the energy absorbing layer. The tests are performed with a free-falling instrumented dummy head which strikes a steel plate that moves horizontally. The oblique impact results in a combination of translation and rotational acceleration that are more realistic are common test methods where helmets are released to a clean vertical impact in the horizontal impact surface. Speeds up to 10m / s (36km / h) can be achieved in both horizontal and vertical directions. In the dummy head, there is a system of nine accelerometers mounted to measure the translation accelerations and rotational accelerations around all axes. In the current test, helmets are released from 0.7 meters. This results in a vertical velocity of 3.7 m / s. The horizontal velocity was selected at 6.7 m / s, resulting in an impact velocity of 7.7 m / s (27.7 km / h) and an impact angle of 29 degrees.

The test shows a reduction in translation acceleration transmitted to the head and a large decrease in rotational acceleration transmitted to the head and in rotation speed of the head.

Fig. 17 shows a graph of the rotation acceleration over time with helmets having sliding promoters (MIPS_350; MIPS_352) compared to regular helmets

534 868 (Org_349; Org_351) without sliding bearing between the fastener and the dummy head.

Fig. 18 shows a graph of the translation acceleration over time with helmets having sliding promoters (MIPS_350; MIPS_352) compared to regular helmets (Org_349; Org_351) without sliding bearings between the fastener and the dummy head.

Note that all embodiments or parts of embodiments as well as all methods or parts of methods can be combined in all different ways. All examples herein are to be seen as parts of the general description and are therefore generally possible to combine in all different ways.

534 868