EP3050449A1

EP3050449A1 - Helmet comprising energy-absorbing layer

Info

Publication number: EP3050449A1
Application number: EP16000174.9A
Authority: EP
Inventors: Alojz Hanuliak
Original assignee: Smid Petr
Current assignee: Smid Petr
Priority date: 2015-01-30
Filing date: 2016-01-26
Publication date: 2016-08-03
Also published as: CZ28115U1

Abstract

Helmet comprising an energy-absorbing layer is made of a firm external skeleton (1) and an internal energy-absorbing layer (2). The internal energy-absorbing layer (2) is made of a moulded foam liner (21), where a plastic strip (22) is attached to its external surface being oriented in the direction towards the internal part of the firm outer skeleton (1) in a fixed or sliding method that is equipped with a bristle material or bristles (23).

Description

Field of the invention

The invention generally relates to protective means of the head, especially a helmet with a firm, but a breakable outer shell, comprising an energy-absorbing layer arranged under such external shell in a sliding way.

Background of the invention

Using a helmet is required for the most sports and working activities to avoid or to reduce the possibility of a skull or brain injury. Such protective means mostly consist of a firm outer shell, made often of plastic or a composite material, and of an energy-absorbing layer called liner. In the most cases, the liner is made of a softer plastic or a similar lining. At the present time, the protective helmets or crash helmets are to be designed to meet requirements stipulated by the law that relate to, besides other things, the maximum acceleration that may occur in the brain at the defined load. Typically tests are performed in which a skull mock-up equipped with a helmet is subject to a radial impact towards the head. Modern helmets have good abilities to absorb energy in the case when the impacts are led in radial direction towards the skull. Energy absorption for other directions is not always optimal.
In case of a radial impact the head motion is accelerated into a translational motion and that results in a linear acceleration of the head. The translational acceleration may cause a fracture of the skull and/or a pressure on the brain tissue or directly a brain tissue injury. Nevertheless, according to statistics are any mere radial impacts rather rare. On the other hand, a mere tangential impact resulting in an angle acceleration of the head is also rare.
Thus the most usual type of impact is an inclined impact which is a combination of radial and tangential forces affecting the head simultaneously which causes e.g. a brain concussion. Rotational acceleration of the skull causes an injury of body elements connecting the brain with the skull and also an injury of the brain.
Example of rotational injuries are subdural hematomas, SDH, bleeding as a consequence of a rupture of a vessel on one side, and on the other side diffuse axonal injury, DAI, that could be summarized as elongation of nerve fibres as a consequence of a high deformation shearing in the brain tissue. Depending on the properties of the rotational force, such as e.g. length of the amplitude and growth rate, either SDH or DAI or their combination occur. Generally, SDH occur in the case of a short duration and with large amplitude, whereas DAI occur when the acceleration load is longer and wider.
The head has natural protective systems that try to damp any deformation forces by means of a hard skull and the spinal fluid below it. During an impact on the skull, the spinal fluid acts as a rotary shock absorber.
The most helmets used presently do not provide any or only a minimum protection against rotational head injuries.
One of solutions that partly protect the head against a rotational injury is provided under pat. US 8578520 , wherein a helmet with a rigid shell is disclosed comprising an energy-absorbing layer and sliding elements. These sliding elements are attached to the internal side of the energy-absorbing layer, so that during an inclined impact only these sliding elements are in motion but not the entire internal energy-absorbing layers.
Another known solution of protective helmets is the solution provided under pat. WO2006005143 wherein a helmet is disclosed with an external layer and an internal layer for the contact with the user's head, comprising further a middle layer consisting of an anisotropic cellular material that has a relatively low resistance to deformation resulting from tangential forces on the helmet.
The anisotropic material may be a foam type or a honeycomb material, the foam is preferably a foam type with closed cells. The helmet allows a partial disturbance of tangential impacts on the helmet that are causing a lower rotational acceleration or a slowdown of the user's head in comparison with using a helmet made from an isotropic foam, and it allows to absorb a huge volume of rotational energy.
Known is also a solution disclosed in pat. EP2428129 where the protective helmet contains an external shell which is made of a hard material. The impact on the head is received through the internal part that is arranged on the internal side of the external shell. The internal part is split into a liner and a double-faced head pad.
A solution which is near to a good solution of this problem is, e.g. the solution provided under pat. US2004250340 , wherein internal and external layers of the protective helmet are disclosed that are overlapping and attached to allow a friction sliding of at least one zone of the external layer over the internal layer. Such friction is reduced by means of randomly arranged ball-shaped surfaces on the outer side of one of internal parts.
All here mentioned solutions are not fully effective during an impact coming from any side.

Summary of the invention

The said drawbacks of the above mentioned solutions that have been used up to now are eliminated to a considerable extent by a helmet comprising an energy-absorbing layer, consisting of a firm external skeleton and an internal energy-absorbing layer, the essence of the invention lies in the fact that the internal energy-absorbing layer consists of a liner made of a moulded foam to which external surface being directed towards the internal part of the firm external skeleton a plastic strip is attached firmly or slidingly that is equipped with a bristle material or bristles, wherein this internal moulded foam liner, skeleton, is together with the attached plastic strip with a bristle material or bristles preferably arranged in a textile casing and/or between textile interlays arranged between the firm external skeleton and the bristle material or bristles to guarantee the minimum adhesion with the external skeleton, wherein in one of further preferable solutions such internal moulded foam liner with the attached plastic strip with the bristle material or bristles is further equipped with a tiltable joint shackle allowing tilting in all directions (3D), and simultaneously forming a flexible connection of the internal moulded foam liner with the external skeleton, wherein the internal moulded foam liner is preferably made of viscoelastic polymer to achieve a higher efficiency of the impact damping. The tiltable joint shackle is in a preferred embodiment made of plastic and/or rubber, where it is tilting at the moment of an impact together with the entire internal moulded foam liner equipped with a plastic strip with bristles that especially at an inclined impact are tilting their whole height smoothly and after this motion has finished, they allow returning of the whole internal moulded foam liner into the original position.

Brief description of the figures on the drawing

The invention is explained by means of the drawings, where Fig. 1 illustrates a total side view of the protective helmet, Fig. 2 is a cross section of the helmet and Fig. 3 is a partial cross section illustrating the internal comfortable foam skeleton of the helmet with the bristle material or bristles in the casing, Fig. 4 is a cross section of the helmet with the tiltable shackle.

Examples of embodiments

Example 1 Helmet for sports in accordance with Fig. 1 and Fig. 4 consists of a firm external skeleton 1 and an internal, energy-absorbing layer 2. The internal, energy-absorbing layer 2 is made of a moulded foam liner 21, and a plastic strip 22 is attached to its outer surface being oriented in the direction towards the internal part of the firm external skeleton 1 , equipped with bristle material or bristles 23.
The internal moulded foam liner 21 with the attached plastic strip 22 with the attached bristle material or bristles 23 is further equipped with a tiltable joint shackle 3, allowing tilting in all directions and simultaneously forming a flexible connection of the internal moulded foam liner 21 with the external skeleton 1. The internal moulded foam liner 21 is made of viscoelastic polymer to achieve a higher efficiency of the impact damping.
Example 2 Helmet for sports in accordance with Fig. 1 and Fig. 3 consists of a firm external skeleton 1 and an internal, energy-absorbing layer 2. The internal, energy-absorbing layer 2 is made of a moulded foam liner 21, and a plastic strip 22 attached to its external surface being oriented in the direction to the internal part of the firm external skeleton 1 equipped with bristle material or bristles 23.
The moulded foam liner 21, the plastic strip 22 equipped with the bristle material or bristles 23 is arranged in a textile casing 24 made of material with a minimum adhesion to the internal wall of the external skeleton 1. There is a connecting element 4, which is Velcro, on the internal surface of the external skeleton 1 and on the outer upper side of the casing 24 to connect both parts of the helmet. The internal moulded foam liner 21 is made of viscoelastic polymer to achieve a higher efficiency of the impact damping.
Example 3 Safety work helmet in accordance with Fig. 1 to Fig. 3 consists of a firm external skeleton 1 and an internal, energy-absorbing layer. The internal, energy-absorbing layer 2 is made of a moulded foam liner 21, and a plastic strip 22 is attached to its external surface being oriented in the direction to the internal part of the firm external skeleton 1 equipped with bristle material or bristles 23.
The moulded foam liner 21, the plastic strip 22, equipped with the bristle material or bristles 23 is arranged in a textile casing 24 made of material with a minimum adhesion to the internal wall of the external skeleton 1. There is a connecting element 4, which is Velcro, on the internal surface of the external skeleton 1 and on the outer upper side of the casing 24 to connect both parts of the helmet. The internal moulded foam liner 21 is made of viscoelastic polymer to achieve a higher efficiency of the impact damping.

The shape of the helmets derived from the purpose of use is not the subject-matter of this invention.

Industrial applicability

Helmet comprising a slidable energy-absorbing layer, consisting of a firm external skeleton and an internal, energy-absorbing layer in accordance with this technical solution is applicable both for sport helmets and for work safety helmets.

Claims

Helmet comprising an energy-absorbing layer, made of a firm external skeleton (1) and an internal, energy-absorbing layer (2), characterised by the fact, that the internal, energy-absorbing layer (2) consists of a moulded foam liner (21), and a plastic strip (22) attached to its outer surface being oriented in direction towards the internal part of the firm external skeleton (1) equipped with bristle material or bristles (23).
Helmet comprising an energy-absorbing layer according to claim 1, characterised by the fact, that the moulded foam liner (21) and the plastic strip (22), equipped with a bristle material or bristles (23) are arranged in a textile casing (24).
Helmet comprising an energy-absorbing layer according to claim 1, characterised by the fact, that the internal moulded foam liner (21) with the attached plastic strip (22) with the attached bristle material or bristles (23) is equipped with a tiltable joint shackle (3) for tilting in all directions, and simultaneously is forming a flexible connection of the internal moulded foam liner (21) with the external skeleton (1).
Helmet comprising an energy-absorbing layer according to claim 1 and 2, characterised by the fact, that a connecting element (4) is attached to the internal surface of the external skeleton (1) and the outer upper side of the textile casing (24) with the moulded foam liner (21) and the plastic strip (22) equipped with bristle material or bristles (23) to connect both parts of the helmet.
Helmet comprising an energy-absorbing layer according to claim 1 to 4, characterised by the fact, that the internal moulded foam liner (21) is made of viscoelastic polymer to achieve a higher efficiency of impact damping.
Helmet comprising an energy-absorbing layer according to claim 4, characterised by the fact, that the connecting element (4) for the connection of the firm external skeleton (1) and the internal, energy-absorbing layer (2) is so called Velcro.
Helmet comprising an energy-absorbing layer according to claim 3, characterised by the fact, that the tiltable joint shackle (3) is made of plastic or rubber.