CA3097730A1 - Shock-absorbing headgear for athletic and other uses - Google Patents

Abstract

A novel shock-absorbing headgear design. A non-newtonian fluid is sandwiched between two outer containment layers of bubbled material. The bubbled nature of the outer containment layers maximizes the surface area exposed to the non-newtonian fluid. On impact, the non-newtonian fluid stiffens, acting as a shock absorber and mitigating impact on the helmet. Headgear of this nature could be used in many applications including sports.

Description

F
SHOCK-ABSORBING HEADGEAR FOR ATHLETIC AND OTHER USES
Obayan L __________________________________________________________________________ This invention is in the field of protective athletic headgear, and more particularly comprises a helmet design with enhanced shock-absorbing abilities to protect the head of the wearer from concussive impact.
Background:
Helmets are used by athletes in many sports as well as people in other applications to protect the head of the wearer from concussive impacts and the like. They protect the brain by reducing impact loading and accelerations experienced by the head.
Particularly in sports such as hockey, football and the like, significant concussive impacts can be encountered during gameplay, and any type of a helmet design that was capable of assisting in ameliorating potential impact injury to the head of the wearer would it is believed to be widely embraced in industry.
A helmet needs to withstand an impact. Impacts comprise high forces accompanying rapid deceleration for a short duration of time.

2 Date Recue/Date Received 2020-11-02 Helmet designs intended to enhance protection from these types of neck, brain and head injuries are based around an understanding of the engineering mechanics of catastrophic damage to the head or the neck. Shock reducing designs and materials, intended to mitigate or negate to the largest degree possible, shock-based injuries, concussions or the like, are well known in the art and there are many types of designs which have been tried in the past.
There are a number of variables and approaches which underpin the concepts of helmet design. Materials of construction as well as to a degree the geometry of the various components of a helmet can be adjusted to mitigate concussive injury or impact to the brain and the head. One of the problems with development of helmets that are sufficiently protective to negate injury is that they require substantial quantities of shock absorbing material. Large quantities of shock absorbing material can result in large and unwieldy apparatus which are not practical particularly in sportswear; smaller and lighter designs are always the gold standard to which equipment designers would be working. If it were possible to create an enhanced helmet design which allowed for a superior shock absorbing quality without the need for a significant amount of shock absorbing material to be used resulting in a lightweight helmet, this would be a significant benefit over the current state-of-the-art.
Helmets of this nature can be used beneficially in many types of sports and activities including hockey, football, cycling, ski racing, automobile or motorcycle racing and the like. A novel helmet design capable of ameliorating dramatic impact and minimizing the

3 Date Recue/Date Received 2020-11-02 likelihood of brain injury or concussion will be understood to be beneficial in any number of these types of industries or activities and are intended for use in all such approaches and activities.
Summary of the Invention:
In shock isolation applications it is desirable to use materials that will deform by large amounts, taking up energy as they do so. To achieve this, the chosen material must include a large degree of damping and non-newtonian foam or liquid could be used for this purpose in the mid-layer of a helmet. "Non-newtonian" is used in reference to the strain response of the material to shear. A Newtonian material has a linear response, while non-newtonian materials do not. Two non-newtonian responses are possible ¨
shear-thickening and shear-thinning. For shock isolation a shear thinning material is desirable.
The general concept of the present invention is to create a helmet design which uses a non-newtonian fluid sandwiched between two "bubbled" layers of very stiff and light material. The key design concept being employed here is that the non-newtonian quality of the fluid sandwiched therein means that the fluid stiffens on the impact, with the bubbles increasing the surface area exposed to the fluid and thereby further diffusing the force through the helmet. The concept of the present invention is that a headwear impact

4 Date Recue/Date Received 2020-11-02 isolation system such as outlined will reduce the impact forces that are experienced on the interior surface of the helmet.
A non-newtonian foam could also be used rather than a non-newtonian fluid ¨
both such approaches are contemplated within the scope of the present invention.
Dependent upon the nature of the ultimate outcome and the shock absorbing quality desired in the product, the size of the bubbles in the outer sandwiching layers could be adjusted to maximize concussive impact.
The invention, shock absorbing headgear for athletic and other uses, comprises a helmet consisting of two helmet shell layers, an interior shell layer and exterior shell layer comprising the interior and exterior surfaces of a protective helmet for wearing on the hand of a wearer. The interior shell layer would be shaped and sized to fit the head of a wearer, either in a custom size or in one of a number of predetermined sizes that could be adapted for use by multiple wearers. Inside of the interior shell layer, the helmet could also be fitted with pieces or layers of additional foam material or other positioning elements used to position or hold the helmet in an appropriate position on the head of the wearer.
The helmet shell layers, namely the interior shell layer and the exterior shell layer, would be joined together around their circumferential edges or in other positions, to position them to define a mid-space therebetween, the mid-space comprising a space in which a

5 Date Recue/Date Received 2020-11-02 mid-layer of a non-newtonian foam or liquid will be disposed. As outlined above, the non-newtonian foam or liquid material used in the mid-layer will stiffen upon the application of shock or pressure.
The outward facing surface of the exterior shell layer, which would face the environment, and the outward facing surface of the interior shell layer which would face the head of the wearer could be smooth or have multiple surface profiles. The interior or inward facing surface of each of the interior shell layer and the exterior shell layer, namely the respective surfaces facing the mid-layer of non-newtonian foam or liquid, would be bubbled. The bubbled interior surface of these shell layers will enhance the force transmitted stability of the surfaces, to maximize the shock absorption quality of the complete sandwich of the two shell layers and the mid-layer of the non-newtonian foam or liquid.
Bubbles of various sizes or geometries could be used on those inward facing surfaces of the shell layers. Size, geometry and reproducibility of the bubbles are variables which could be tested and used in different embodiments of helmets or headgear in accordance with the remainder of the present invention.
The following figure demonstrates one cross-sectional example of layers which could be used in a helmet design in accordance with the present invention. From the top, down to the bottom, the layers comprise interior and exterior shell layers comprised of bubbled polycarbonate, for example, with a non-newtonian D30 foam layer therebetween.
Also

6 Date Recue/Date Received 2020-11-02 shown is a low density polyethylene foam layer (LDPE) which could be used to enhance the comfort of the helmet on the head of the wearer and appropriately hold it in position.
A steel layer is also shown. Various helmet designs may or may not include the LDPE or steel additional layers - these will be understood to be optional within the overall concept of the present invention:
TOP
PC
riffili ryta DID
PC
LOPE
steel The following figure shows a cross-sectional view of an alternate embodiment in which the size and shape of the bubbles in the shell layers has been changed:
TOP
DID
g Ste&

7 Date Recue/Date Received 2020-11-02 In a further demonstrative embodiment, the positioning of the bubbles on the interior bubbled surfaces of the shell layers could also be staggered in relationship to each other, so that each bubble fits into the space between bubbles and the opposing layer rather than being positioned across from each other. This "shifted" configuration will be understood to also be within the scope of the present invention::
-.411111L¨ -.A11111hibp....
4x,----,1- '-',---- -,';,--:, =-: - , - ,, ' While the bubbles on the surface of the materials used could be spherically shaped, additional variations can also be contemplated and which the bubbles have an elliptic or an elongated profile, such as shown in the following two additional figures:
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'-",..k:z;,., di- ¨

8 Date Recue/Date Received 2020-11-02 P.!
.19.011111.4 ========11 A sample test was conducted with respect to a prototype material sandwich for use in the construction of a helmet of this nature, having 20 mm x 5 mm bubble configuration or .. geometry. The following is the approximate geometry of that particular material sandwich as already shown above:
TaP
IPC

PC
" /7/
LID E
BOTTOM
steel In a computerized drop simulation, the von Mises stress was monitored at six different nodes from the top layer (the exterior shell layer) of the sample, and at six nodes of the interior shell layer. Calculated drop test values at each node are averaged and graphed ¨

9 Date Recue/Date Received 2020-11-02 the difference between the top and bottom responses shown below indicate the force transmitted stability of the layers, including the demonstration of the fact that stress transmitted stability remained reasonably constant and low for the interior shell layer measurements, even where extreme force was exerted upon the exterior shell layer. The bubbled sample performed well at reducing the stress transmitted through the layers and the sandwich in the direction of the head of the wearer.
Von Mises Stress Transmissibility - 20mmx5mm a 2.00E406 flAIT\IP.V \Lewd \o""/
0.00E-40) 50 11X1 150 ZSO ' Iii:
It will be understood that various types of materials with interior surface profiles of the interior and exterior shell layers could be used without departing from the scope and intention of the present invention. Any number of different types of material confining and impact absorbing materials with an interior bubbled surface, whether that doubled surface be formed by injection, machining or otherwise, are all contemplated within the scope of the present invention.
Any type of a piece of headgear comprised of two material confining and impact absorbing shell layers with bubbled interior surfaces facing each other and confining or Date Recue/Date Received 2020-11-02 sandwiching a non-newtonian shear-thinning fluid or foam will be understood to be within the scope of the present invention.
In a further approach, it is also contemplated that while bubbled geometries of the interior facing surfaces of the shell layers would be successful in reducing the transmission of shock from outside to the interior of the helmet, other geometries could also be used for the shell layers. For example, in certain embodiments, it is believed that the interior and exterior shell layers might have interior facing surfaces that simply defined an airgap between those layers and the non-newtonian foam or liquid. Air gaps allow for larger deflections of the non-newtonian foam, absorbing more energy. In such an embodiment, geometries that are easier to manufacture than bubbles of various shapes could be used, to optimize the construction of the helmet for a trade-off between performance and ease of manufacture. For example, it may be desired to contemplate the use of an interior facing square column surface rather than a bubbled surface, defining and supporting the mid-layer of non-newtonian foam or liquid, as follows:
i Date Recue/Date Received 2020-11-02 It will be understood that any number of different types of interior surface profiles could be used to support or engage the mid-layer of non-newtonian foam or liquid in the headgear of the present invention and any such construction approach is contemplated within the scope of the present invention.
In addition to the headgear comprising the material sandwich of the interior and exterior shell layers confining a non-newtonian foam or liquid layer, a pre-manufactured material sandwich comprising the interior and exterior shell layers with the non-newtonian foam or liquid layer fixed therebetween for use in the manufacture of headgear is also explicitly contemplated within the scope of the present invention ¨ for example sheets of this sandwich material could be produced for cutting and moulding into headgear dependent upon the desired method of manufacture and this type of a material will be understood to be within the scope of the present invention along with the finished headgear.
Also encompassed is the method of manufacture of a shock absorbing helmet comprising the fixing of a non-newtonian foam or liquid layer between interior and exterior shell layers as defined.
It will be apparent to those of skill in the art that by routine modification the present invention can be optimized for use in a wide range of conditions and application. It will also be obvious to those of skill in the art that there are various ways and designs with Date Recue/Date Received 2020-11-02 which to produce the apparatus and methods of the present invention. The illustrated embodiments are therefore not intended to limit the scope of the invention, but to provide examples of the apparatus and method to enable those of skill in the art to appreciate the inventive concept.
Those skilled in the art will recognize that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the scope of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context.
The terms "comprises" and "comprising" should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps not expressly referenced.

Date Recue/Date Received 2020-11-02

Claims

Claims:

1. A shock-absorbing helmet for athletic and other uses in accordance with the disclosure outlined herein.