The invention relates generally to a sports helmet providing protection against rotational impacts.
Helmets are worn in sports and other activities to protect their wearers against head injuries. To that end, helmets typically comprise a rigid outer shell and inner padding to absorb energy when impacted.
Various types of impacts are possible. For example, a helmet may be subjected to a radial impact in which an impact force is normal to the helmet and thus tends to impart a translational movement to the helmet. A helmet may also be subjected to a rotational impact which tends to impart an angular movement to the helmet. The rotational impact can be a tangential impact in which an impact force is tangential to the helmet or, more commonly, an oblique impact in which an impact force is oblique to the helmet and has both a radial impact force component and a tangential impact force component.
A rotational impact results in angular acceleration of the wearer's brain within his/her skull. This can cause serious injuries such as concussions, subdural hemorrhage, or nerve damage. Linear acceleration also results if the rotational impact is oblique.
Although helmets typically provide decent protection against radial impacts, their protection against rotational impacts is usually deficient. This is clearly problematic given the severity of head injuries caused by rotational impacts.
For these and other reasons, there is a need for improvements directed to providing a sports helmet providing protection against rotational impacts.
According to an aspect of the invention, there is provided a sports helmet for protecting a head of a wearer and comprising a rotational impact protection device.
According to one aspect, the invention provides a sports helmet for protecting a head of a wearer, the sports helmet defining a cavity for receiving the wearer's head, the sports helmet comprising: (a) an outer shell comprising an external surface of the sport helmet; (b) inner padding disposed between the outer shell and the wearer's head when the sports helmet is worn; (c) an adjustment mechanism operable by the wearer to vary an internal volume of the cavity to adjust a fit of the sports helmet on the wearer's head; and (d) a rotational impact protection device disposed between the external surface of the sport helmet and the wearer's head when the sport helmet is worn, the rotational impact protection device comprising a surface movable relative to the external surface of the sport helmet in response to a rotational impact on the outer shell to absorb rotational energy from the rotational impact, the surface of the rotational impact protection device undergoing displacement when the adjustment mechanism is operated by the wearer to vary the internal volume of the cavity.
According to another aspect, the invention provides a sports helmet for protecting a head of a wearer, the sports helmet defining a cavity for receiving the wearer's head, the sports helmet comprising: (a) an outer shell comprising an external surface of the sports helmet; (b) inner padding disposed between the outer shell and the wearer's head when the sports helmet is worn; (c) an adjustment mechanism for adjusting an internal volume of the cavity to adjust a fit of the sports helmet on the wearer's head; and (d) a floating liner disposed between the inner padding and the wearer's head when the sports helmet is worn, the floating liner being movable relative to the outer shell in response to a rotational impact on the outer shell to absorb rotational energy from the rotational impact, the floating liner being configured to accommodate adjustment of the internal volume of the cavity when the adjustment mechanism is operated by the wearer.
According to another aspect, the invention provides a sports helmet for protecting a head of a wearer, the sports helmet defining a cavity for receiving the wearer's head, the sports helmet comprising: (a) an outer shell comprising an external surface of the sports helmet; (b) inner padding disposed between the outer shell and the wearer's head when the sports helmet is worn; and (c) a floating liner disposed between the inner padding and the wearer's head when the sports helmet is worn, the floating liner being movable relative to the outer shell in response to a rotational impact on the outer shell to absorb rotational energy from the rotational impact, the floating liner comprising stretchable material such that at least part of the rotational energy is absorbed by stretching of the stretchable material.
According to a further aspect, the invention provides a sports helmet for protecting a head of a wearer, the sports helmet defining a cavity for receiving the wearer's head, the sports helmet comprising: (a) an outer shell comprising an external surface of the sports helmet; (b) inner padding disposed between the outer shell and the wearer's head when the sports helmet is worn; and (c) a floating liner disposed between the inner padding and the wearer's head when the sports helmet is worn, the floating liner being movable relative to the outer shell and the inner padding in response to a rotational impact on the outer shell to absorb rotational energy from the rotational impact, the floating liner comprising an inner surface for contacting the wearer's head and an outer surface facing the inner padding, the outer surface of the floating liner being in frictional engagement with the inner padding in response to the rotational impact such that at least part of the rotational energy is dissipated by friction between the inner padding and the outer surface of the floating liner, the outer surface of the floating liner having a coefficient of friction with the inner padding of at least 0.2 measured according to ASTM G115-10.
According to another aspect, the invention provides a sports helmet for protecting a head of a wearer, the sports helmet defining a cavity for receiving the wearer's head, the sports helmet comprising: (a) an outer shell comprising an external surface of the sports helmet; (b) inner padding disposed between the outer shell and the wearer's head when the sports helmet is worn; (c) a floating liner disposed between the inner padding and the wearer's head when the sports helmet is worn, the floating liner being movable relative to the outer shell in response to a rotational impact on the outer shell to absorb rotational energy from the rotational impact; and (d) an occipital pad for engaging an occipital region of the wearer's head, the occipital pad being selectively movable relative to the outer shell, the floating liner being movable with the occipital pad during adjustment of the occipital pad.
According to a further aspect, the invention provides a sports helmet for protecting a head of a wearer, the sports helmet defining a cavity for receiving the wearer's head, the sports helmet comprising: (a) an outer shell comprising an external surface of the sports helmet; (b) inner padding disposed between the outer shell and the wearer's head when the sports helmet is worn; and (c) a floating liner disposed between the inner padding and the wearer's head when the sports helmet is worn, the floating liner being movable relative to the outer shell in response to a rotational impact on the outer shell to absorb rotational energy from the rotational impact, the floating liner comprising a top portion for contacting a top region of the wearer's head and a plurality of branches extending downwardly from the top portion of the floating liner and arranged for contacting the wearer's head.
According to another aspect, the invention provides a sports helmet for protecting a head of a wearer, the sports helmet defining a cavity for receiving the wearer's head, the sports helmet comprising: (a) an outer shell comprising an external surface of the sports helmet; (b) inner padding disposed between the outer shell and the wearer's head when the sports helmet is worn; and (c) a floating liner disposed between the inner padding and the wearer's head when the sports helmet is worn, the floating liner being movable relative to the outer shell in response to a rotational impact on the outer shell to absorb rotational energy from the rotational impact, wherein an interface between the floating liner and the inner padding is fastener-free at an apex of the interface between the floating liner and the inner padding.
According to a further aspect, the invention provides a hockey or lacrosse helmet for protecting a head of a hockey or lacrosse player, the helmet defining a cavity for receiving the player's head, the helmet comprising: (a) an outer shell comprising an external surface of the helmet, the outer shell comprising a first shell member and a second shell member moveable relative to one another for adjusting an internal volume of the cavity to adjust a fit of the helmet on the player's head; (b) inner padding disposed between the outer shell and the player's head when the helmet is worn; and (c) a floating liner disposed between the inner padding and the player's head when the helmet is worn, the floating liner being movable relative to the outer shell in response to a rotational impact on the outer shell to absorb rotational energy from the rotational impact, the floating liner being configured to accommodate adjustments of the internal volume of the cavity when the first shell member and the second shell member are moved relative to one another.
These and other aspects of the invention will now become apparent to those of ordinary skill in the art upon review of the following description of embodiments of the invention in conjunction with the accompanying drawings.
A detailed description of embodiments of the invention is provided below, by way of example only, with reference to the accompanying drawings, in which:
It is to be expressly understood that the description and drawings are only for the purpose of illustrating certain embodiments of the invention and are an aid for understanding. They are not intended to be a definition of the limits of the invention.
To facilitate the description, any reference numeral designating an element in one figure will designate the same element if used in any other figures. In describing the embodiments, specific terminology is resorted to for the sake of clarity but the invention is not intended to be limited to the specific terms so selected, and it is understood that each specific term comprises all equivalents.
Unless otherwise indicated, the drawings are intended to be read together with the specification, and are to be considered a portion of the entire written description of this invention. As used in the following description, the terms “horizontal”, “vertical”, “left”, “right”, “up”, “down” and the like, as well as adjectival and adverbial derivatives thereof (e.g., “horizontally”, “rightwardly”, “upwardly”, “radially”, etc.), simply refer to the orientation of the illustrated structure. Similarly, the terms “inwardly,” “outwardly” and “radially” generally refer to the orientation of a surface relative to its axis of elongation, or axis of rotation, as appropriate.
The sports helmet 10 defines a cavity 13 for receiving the wearer's head 11 to protect the wearer's head 11 when the sports helmet 10 is impacted (e.g., when the sports helmet 10 hits a board or an ice or other playing surface or is struck by a puck, ball, a lacrosse stick or a hockey stick or when the player is receiving a hit (body check) by another player and the head of the player is hit directly or indirectly). More particularly, in this embodiment, the sports helmet 10 is designed to provide protection against a radial impact in which an impact force is normal to the sports helmet 10 and thus tends to impart a translational movement to the sports helmet 10 (“radial” is used herein in a general sense to mean that the radial impact is along a direction which is perpendicular to a plane that is tangential to the helmet's external surface and, since a helmet is generally round, such impact will extend along a radial direction). In addition, the sports helmet 10 is designed to provide protection against a rotational impact which tends to impart an angular movement to the sports helmet 10. A rotational impact can be a tangential impact in which an impact force is tangential to the sports helmet 10 or, more commonly, an oblique impact in which an impact force is oblique to the sports helmet 10 and has a radial impact force component and a tangential impact force component. A rotational impact thus exerts a rotational force on the sports helmet 10, i.e., the tangential impact force in the case of a tangential impact and the tangential impact force component in the case of an oblique impact.
The sports helmet 10 protects various regions of the wearer's head 11. As shown in
The sports helmet 10 has an external surface 18 and an internal surface 20 that contacts the wearer's head 11 when the sports helmet 10 is worn. The sports helmet 10 has a front-back axis FBA, a left-right axis LRA, and a vertical axis VA which are respectively generally parallel to a dorsoventral axis, a dextrosinistral axis, and a cephalocaudal axis of the wearer when the sports helmet 10 is worn and which respectively define a front-back direction, a left-right direction, and a vertical direction of the sports helmet 10. Since they are generally oriented longitudinally and transversally of the sports helmet 10, the front-back axis FBA and the left-right axis LRA can also be referred to as a longitudinal axis and a transversal axis, respectively, while the front-back direction and the left-right direction can also be referred to a longitudinal direction and a transversal direction.
In response to an impact, the sports helmet 10 absorbs energy from the impact to protect the wearer's head 11. In particular, in this embodiment, as further discussed below, the sports helmet 10 comprises a rotational impact protection device for causing an angular movement of its external surface 18 relative to its internal surface 20 in response to a rotational impact to absorb rotational energy from the rotational impact. This reduces rotational energy transmitted to the wearer's head 11 and therefore reduces angular acceleration of the wearer's brain within his/her skull.
In this embodiment, the sports helmet 10 comprises an outer shell 12, inner padding 15, and a floating liner 50, which implements the rotational impact protection device.
As further discussed later, the floating liner 50 is allowed a certain degree of freedom of movement (for that reason it is referred to as “floating”) and constitutes an energy-absorbing structure that takes up a certain amount of energy during a rotational impact. The sports helmet 10 also comprises ear loops 14 and a chinstrap 16 for securing the sports helmet 10 to the wearer's head 11. The sports helmet 10 further comprises ear protectors 32 for protecting the left and right ears of the wearer.
The outer shell 12 provides strength and rigidity to the sports helmet 10. To that end, the outer shell 12 is made of rigid material. For example, in various embodiments, the outer shell 12 may be made of thermoplastic material such as polyethylene, polyamide (nylon), or polycarbonate, of thermosetting resin, or of any other suitable material. The outer shell 12 has an inner surface 17 facing the inner padding 15 and an outer surface 19 opposite the inner surface 17. In this example of implementation, the outer surface 19 of the outer shell 12 constitutes the external surface 18 of the sports helmet 10.
The outer shell 12 comprises a front outer shell member 22 and a rear outer shell member 24 that are connected to one another. The front outer shell member 22 comprises a top portion 21 for facing at least part of the top region TR of the wearer's head 11, a front portion 23 for facing at least part of the front region FR of the wearer's head 11, and left and right side portions 25, 27 extending rearwardly from the front portion 23 for facing at least part of the left and right side regions LS, RS of the wearer's head 11. The rear outer shell member 24 comprises a top portion 29 for facing at least part of the top region TR of the wearer's head 11, a back portion 31 for facing at least part of the back region BR of the wearer's head 11, an occipital portion 37 for facing at least part of the occipital region OR of the wearer's head 11, and left and right side portions 33, 35 extending forwardly from the back portion 31 for facing at least part of the left and right side regions LS, RS of the wearer's head 11.
The sports helmet 10 may be adjustable in order to adjust how it fits on the wearer's head 11. To that end, the sports helmet 10 comprises an adjustment mechanism 40 for adjusting a fit of the sports helmet 10 on the wearer's head 11. The adjustment mechanism 40 allows the fit of the sports helmet 10 to be adjusted by being operable by the wearer to vary the internal volume of the cavity 13 of the sports helmet 10. This can be done by adjusting one or more internal dimensions of the cavity 13 of the sports helmet 10, such as a front-back internal dimension FBD of the cavity 13 in the front-back direction of the sports helmet 10 and/or a left-right internal dimension LRD of the cavity 13 in the left-right direction of the sports helmet 10, as shown in
More particularly, in this embodiment, the outer shell 12 and the inner padding 15 are adjustable to adjust the fit of the sports helmet 10 on the wearer's head 11. To that end, in this case, the front outer shell member 22 and the rear outer shell member 24 are movable relative to one another to adjust the fit of the sports helmet 10 on the wearer's head 11. The adjustment mechanism 40 is connected between the front outer shell member 22 and the rear outer shell member 24 to enable adjustment of the fit of the sports helmet 10 by moving the outer shell members 22, 24 relative to one another. In this example, relative movement of the outer shell members 22, 24 for adjustment purposes is in the front-back direction of the sports helmet 10 such that the front-back internal dimension FBD of the cavity 13 of the sports helmet 10 is adjusted. This is shown in
As best shown in
For example, the actuator 41 may comprise first and second pairs of teeth 42, 43 extending generally transversely relative to the longitudinal axis FBA. The actuator 41 can be moved (in this case pivoted) by the wearer between a locked position, in which the first and second pairs of teeth 42, 43 engage in first and second plurality of pairs of apertures 44, 45 provided on the front outer shell member 22 (as best shown in
As shown in
The outer shell 12 may be implemented in various other ways in other embodiments. For example, in other embodiments, the outer shell 12 may be a single-piece shell. In such embodiments, the adjustment mechanism 40 may comprise an internal adjustment device located within the sports helmet 10 and having a head-facing surface movable relative to the wearer's head 11 in order to adjust the fit of the sports helmet 10. For instance, in some cases, the internal adjustment device may comprise an internal pad member movable relative to the wearer's head 11 or an inflatable member which can be inflated so that its surface can be moved closer to or further from the wearer's head 11 to adjust the fit.
The inner padding 15 is disposed on the inner surface 17 of the outer shell 12 such that, in use, it is disposed between the outer shell 12 and the wearer's head 11 to absorb impact energy when the sports helmet 10 is impacted. As best seen in
As best shown in
Each of the inner pad members 15A, 15B, 15C, 15D, 15E of the inner padding 15 comprises shock-absorbing material to absorb impact energy when the sports helmet 10 is impacted. For example, in this embodiment, each of the inner pad members 15A, 15B, 15C, 15D, 15E comprises polymeric cellular material. For instance, the polymeric cellular material may comprise polymeric foam such as expanded polypropylene (EPP) foam, expanded polyethylene (EPE) foam, or any other suitable polymeric foam material and/or may comprise expanded polymeric microspheres (e.g., Expancel™ microspheres commercialized by Akzo Nobel). Any other material with suitable impact energy absorption may be used for the inner padding 15 in other embodiments.
As best shown in
The inner padding 15 may be implemented in various other ways in other embodiments. For example, in other embodiments, the inner padding 15 may comprise any number of pad members (e.g.: two pad members such as one pad member that faces at least part of the front region FR, top region TR, and left and right side regions LS, RS of the wearer's head 11 and another pad member that faces at least part of the back region BR, top region TR, and left and right side regions LS, RS of the wearer's head 11; a single pad that faces at least part of the front region FR, top region TR, left and right side regions LS, RS, and back region BR of the wearer's head 11; etc.).
The floating liner 50 provides impact protection, including rotational impact protection, when the sports helmet 10 is impacted. The liner 50 is “floating” in that it is movable relative to one or more other components of the helmet 10 in response to a rotational impact on the outer shell 12. This movement allows rotational energy from the rotational impact to be absorbed instead of being transmitted to the wearer's head 11. The floating liner 50 comprises a layer of material located between the external surface 18 and the internal surface 20 of the helmet 10. The layer of material of the floating liner 50 may include a single material constituent or different material constituents and/or may have a constant thickness or a variable thickness.
As best shown in
An example of how the floating liner 50 provides rotation impact protection in this embodiment is illustrated in
Movement of the outer shell 12 and the inner padding 15 relative to the floating liner 50 creates friction between the floating liner 50 and the inner padding 15. This friction dissipates rotational energy associated with the rotational impact RI. In addition, movement of the outer shell 12 and the inner padding 15 relative to the floating liner 50 induces an elastic deformation of the floating liner 50. More particularly, in this embodiment, the floating liner 50 stretches so as to curve in a direction of the rotational force RF. This stretching of the floating liner 50 absorbs rotational energy associated with the rotational impact RI.
In addition to its rotational impact protection, in this embodiment, the floating liner 50 also provides radial impact protection. More particularly, the floating liner 50 is elastically compressible in response to a linear impact force (i.e., a radial impact force in the case of a radial impact or a radial impact force component in the case of an oblique impact) to absorb energy by elastic compression. The floating liner 50 therefore implements a padding layer.
With reference to
The floating liner 50 may be made of any suitable material to achieve its impact protection function. In this embodiment, in order to absorb energy by elastic deformation, the floating liner 50 comprises elastic material that is elastically stretchable to absorb rotational energy associated with a rotational force when the sports helmet 10 is impacted. Also, in this case, the elastic material of the floating liner 50 is elastically compressible to absorb impact energy associated with a linear force when the sports helmet 10 is impacted. The elastic material of the floating liner 50 may thus be an elastically stretchable compressible impact-absorbing material. For example, in some embodiments, the elastic material of the floating liner 50 may comprise elastomeric material (e.g., elastomeric polyurethane foam such as PORON XRD foam commercialized by Rogers Corporation or any other suitable elastomeric foam).
As shown in
The floating liner 50 may be fastened to a remainder of the sports helmet 10 in various ways. For example, as best shown in
The fastening points 601-605 of the floating liner 50 may comprise respectively fastening members 711-715 which are fastened to the outer shell 12 and to which the floating liner 50 is attached. More particularly, the fastening members 711-715 are fastened to the outer shell 12 via mechanical fasteners (e.g., screws 95) and to the floating liner 50 via stitches. For instance, as shown in
The fastening members 711-755 may be implemented in various other ways in other embodiments. For example, the fastening members 711-715 may be affixed directly to the inner padding 15 such that the floating liner 50 is rather affixed to the inner padding 15 instead to the outer shell 12 or the fastening members 711-715 may be affixed to the outer shell 12 while portions of the padding 15 are located between one or more of the fastening members 711-715 and the outer shell 12 such that the floating liner 50 is affixed to the outer shell 12 through the inner padding 15.
The fastening members 711-755 may be made of any suitable material. For example, in this embodiment, the fastening members 711-755 are made of polymeric material (e.g., polypropylene, polyethylene, nylon, polycarbonate or polyacetal, or any other suitable plastic). In particular, in this example, the polymeric material of the fastening members 711-755 is such that each of these fastening members is more rigid than the floating liner 50 to enable the floating liner 50 to stretch when the helmet 50 is rotationally impacted. The fastening members 711-755 may be made of various other materials in other embodiments (e.g., metallic material).
As best shown in
The occipital pad 36 may be made of any suitable padding material. For example, in some embodiments, the occipital pad 36 may comprise polymeric foam such as expanded polypropylene (EPP) foam, expanded polyethylene (EPE) foam, foam having two or more different densities (e.g., high-density polyethylene (HDPE) foam and low-density polyethylene foam), or any other suitable foam. Other materials may be used for the occipital pad 36 in other embodiments.
The occipital pad 36 is supported by a support 76 which is movable relative to the second shell member 24 in order to move the occipital pad 36. As best shown in
As best shown in
As best shown in
As best shown in
As best shown in
A more detailed description of the floating liner 50 and its method of operation in this embodiment are provided below.
The floating liner 50 is a spider-like structure that includes the top portion 54 and a series of branches which extend downwardly and connect the spider-like structure to the lower portion of the sports helmet 10 near the respective distal ends of the branches. More particularly, the floating liner 50 has an elongated band-like front segment or branch 701, an opposed elongated rear band-like segment or branch 704, lateral front band-like segments or branches 702, 706, lateral rear band-like segments or branches 703, 705, all extending downwardly from the top portion 54. The lateral front band-like segments or branches 702, 706 are provided with side extensions 110 that extend toward and connect with the front band-like segment 701. The extensions 110 run generally along the lower periphery of the helmet when the floating liner 50 is installed in the sports helmet 10.
The various components of the floating liner 50 are attached to one another by stitching. In this example of implementation, stitches 1201-120S connect the various components of the floating liner 50 into its dome shape. Other forms of attachment may be used in other embodiments. For example, the various components can be glued to one another or the floating liner 50 can be formed as a single piece, such as by die-cutting it from a blank of material.
Upon assembly, the floating liner 50 thus has the front and rear segments or branches 701, 704 that are elongated and extend along the longitudinal axis FBA of the sports helmet 10. The front and rear segments or branches 701, 704 connect with the top portion 54 such as to define openings, slots or slits 1221, 1222 with the front and rear segments 701, 704. The openings, slots or slits 1221, 1222 make the floating liner 50 somewhat stretchable in the longitudinal direction (further to the inherent stretchability of the material from which the floating liner 50 is made) such as to accommodate changes in the internal volume defined by the sports helmet 10. To provide a better fit, the sports helmet 10 can be designed to be adjustable, as described in greater detail earlier. The adjustability is such that the internal volume of the sports helmet 10 changes to make it larger or smaller according to the particular size of the wearer's head 11. The openings, slots or slits 1221, 1222 can allow the floating liner 50 to expand or contract within the helmet's cavity 13 when an adjustment is made and thus prevent the floating liner 50 from bunching.
The lateral front and rear segments or branches 702, 703, 705, 706 extend along the transversal axis LRA of the sports helmet 10. Between the lateral front and rear segments or branches 702, 703 and 705, 706, left and right spaces 124, 126 are defined and these left and right spaces 124, 126 register with the respective left and right ears of the wearer. The spaces 124, 126 provide clearance to receive various components of the sports helmet 10 that protect the ears.
This arrangement is such that the floating liner 50 is retained to the outer shell 12 at a plurality of spaced apart locations that are adjacent the lower edge of the outer shell 12. It is understood that the floating liner 50 may be retained directly to the inner padding 15 via the fastening members 711-755 or be retained to the outer shell 12 while portions of the inner padding 15 are located between the fastening members 711-755 and outer shell 12. The floating liner 50 is retained at the front and at two locations on each side, one being in front the ear and near the temple region and the other behind the ear. At the back, the floating liner 50 connects with the occipital pad 36, which moves with relation to the outer shell 12, as described earlier.
The various components of the floating liner 50 may be made from material that has a constant thickness or the thickness may vary. In the example shown in the drawings, a variable thickness material is being used to provide, in addition to the rotational impact protection, protection against radial impacts.
To avoid the floating liner 50 from projecting too far inwardly in the sports helmet 10 with relation to the inner surface of the inner padding 15 on which the floating liner 50 rests, the inner padding 15 can be provided with one or more recesses in which one or more parts of the floating liner 50 can fit. With reference to
The floating liner 50 is a component of the sports helmet 10 that contributes to protect the head 11 of the wearer during an impact that has a rotational force component and which imparts an angular movement to the head 11. As briefly discussed earlier, several energy absorption mechanisms operate in conjunction with one another to take up at least a component of the energy in the impact and thus limit the residual energy that is transmitted to the wearer's head 11.
Without intent of being bound by any particular theory, the inventors have identified four primary energy absorption mechanisms. The first is the ability of the floating liner 50 to stretch during a relative movement between the floating liner 50 and the remainder of the helmet's structure which is rigid and moves in unison during the impact. Typically, the main components of the helmet structure that move in relation to the floating liner 50 are the outer shell 12 and the inner padding 15. Conceptually speaking, the sports helmet 10 thus provides two elements that can move one with relation to the other during a rotational impact. One of the elements is the outer shell/inner padding combination. The other element is the floating liner 50 which constitutes the interface between the outer shell/inner padding combination and the wearer's head 11. The floating liner 50 is designed to closely fit on the head 11 and at the same time is attached to the outer shell 12 of the sports helmet 10 via rigid mounting points that include the fastening members 711 to 715 and the occipital pad 36. Thus, in the course of an impact that tends to impart an angular movement to the sports helmet 10, the outer shell/inner pad combination will tend to move with relation to the floating liner 50 that is in contact with the head 11. The rigid mounting points will thus distort the floating liner 50 and stretch various parts of the floating liner 50. As the material of the floating liner 50 is being stretched, it absorbs energy.
The ability of the floating liner 50 to absorb energy can be enhanced by proper selection of the material from which the floating liner 50 is made and also by the structure of the floating liner 50. From a structural point of view, the floating liner 50 is constructed as a series of elongated segments or branches (the front segment or branch 701, rear segment or branch 704, and lateral front and rear segments or branches 702, 703, 705, 706) that extend downwardly from the top portion 54 of the floating liner 50 and thus run from the top of the head 11 downwardly (when taking the head 11 of the wearer as a reference). When an angular movement occurs, the extremities of those segments or branches, which are affixed to the outer shell/inner pad combination, are pulled as the outer shell/inner pad combination angularly moves, stretching the material from which the segments are made.
From a material point of view, the material of the floating liner 50 may be such that, when stretched, at least some degree of energy is absorbed in the material. In a specific example of implementation the material can be characterized by using the ASTM D2632-01 Standard Test method for rubber property-Resilience by Vertical rebound. The material of the floating liner 50 that manifests energy absorption may have, according to this test a resilience of less than 30%, preferably less than 20%, even more preferably less than 15% and most advantageously less than 10%. A specific material that has been found to provide energy absorption in a helmet for use in hockey is sold under the trademark PORON XRD.
The second energy absorption mechanism that works in conjunction with the stretchability of the floating liner 50 is the frictional interface between the floating liner 50 and the inner padding 15. As the floating liner 50 moves with relation to the outer shell/inner padding combination, the presence of friction at the interface dissipates energy during the movement, by generating heat. From a material perspective, the degree of friction that exists between the floating liner 50 and the inner padding 15 is controlled such that enough friction exists in order to enhance energy dissipation and at the same time the friction does not exceed a level at which the movement will be inhibited.
In a specific and non-limiting example of implementation, the degree of friction between the floating liner 50 and the mating surface of the inner pad is characterized by the ASTM G115-10 Standard Guide for Measuring and Reporting Friction Coefficients. The friction coefficient between the floating liner 50 and the inner padding 15 is of at least 0.2, preferably of at least 0.3, more preferably of at least 0.4, even more preferably of at least 0.5 and most advantageously in the range of about 0.5 to about 0.6.
Note that very high coefficients of friction may not be optimal since the amount of effort required to initiate the movement between the floating liner 50 and the inner padding 15 can become too high. In this case, the sports helmet 10 may not respond to low level rotational impacts where the angular acceleration imparted to the outer shell 12 and inner padding 15 is not sufficient to overcome the friction between the floating liner 50 and the inner padding 15. It is thus preferred to keep the coefficient of friction between the floating liner 50 and the inner padding 15 to a level that does not exceed 0.75 and more preferably is at 0.7 or below.
The third energy absorption mechanism is compression of the material of the floating liner 50. This third mechanism may manifest itself when a radial impact force component has the effect of pushing the sports helmet 10 toward the head, in addition to imparting to the sports helmet 10 angular motion. The compression of the material will absorb some quantity of energy that depends on the degree of compression. From that perspective, a thicker floating liner 50 will be able to absorb more energy as a result of compression, than a thinner floating liner 50. Also, while certain areas of the material of the floating liner 50 may stretch, other areas of the floating liner's material may compress tangentially and this may also contribute to energy absorption.
The fourth energy absorption mechanism is the inertia of the outer shell 12/inner padding 15 combination. Since this structure moves with relation to the head 11 of the wearer as a result of a rotational impact, the angular motion imparted to the structure requires some amount of energy. The fourth energy absorption mechanism is independent of the floating liner 50. It should also be noted that the fourth energy absorption mechanism can be maximized by decreasing the degree of friction between the floating liner 50 and the inner padding 15. Such a decrease of friction will increase the range of movement of the outer shell 12/inner padding 15 combination such that the energy intake by the angularly accelerated mass will increase. However, a decrease of the degree of friction between the floating liner 50 and the inner padding 15 will also have the undesirable effect of decreasing the efficacy of the second energy absorption mechanism that relies on friction. The higher the friction, the more energy absorption will occur. On balance, the energy absorption mechanism that works on the basis of friction is preferred over the one that works on the basis of inertia since it is believed to be more effective. Accordingly, an interaction between the floating liner 50 and the inner padding 15 that largely favors slidability at the expense of friction is not desirable.
The various energy absorption mechanisms described above contribute differently to the overall ability of the sports helmet 10 to protect against rotational impacts. Generally, it is believed that, in the helmet structure described herein, the cumulative effect of the first three energy absorption mechanisms (i.e., the stretchability of the floating liner 50, the frictional engagement between the floating liner 50 and the inner padding 15, and the compression of the material of the floating liner 50) outweigh significantly the effect of the fourth energy absorption mechanism (i.e., the inertia of the outer shell 12/inner padding 15 combination).
The sports helmet may comprise an adjustment mechanism such as a movable inner pad member or an inflatable inner member for adjusting the internal volume of the cavity 13 to adjust the fit of the sports helmet 10 on the wearer's head and the floating liner 50 is movable relative to the outer shell 12 in response to a rotational impact on the outer shell 12 to absorb rotational energy from the rotational impact and the floating liner 50 is configured to accommodate adjustments of the internal volume of the cavity 13 using the adjustment mechanism.
The sports helmet may comprise a rotational impact protection device disposed between the external surface 18 of the sports helmet 10 and the wearer's head when the sport helmet 10 is worn, the rotational impact protection device comprising a surface 59 movable relative to the external surface 18 of the sports helmet 10 in response to a rotational impact on the outer shell 12 to absorb rotational energy from the rotational impact, the surface 59 of the rotational impact protection device undergoing displacement when the adjustment mechanism is operated by the wearer to vary the internal volume of said cavity.
In one variant, the rotational impact protection device is the floating liner 50 that is movable relative to the outer shell 12 in response to a rotational impact on the outer shell 12 to absorb rotational energy from the rotational impact and that is configured to accommodate adjustments of the internal volume of the cavity 13 when the first shell member 22 and the second shell member 24 are moved relative to one another. The floating liner 50 may comprise stretchable material such that at least part of the rotational energy is absorbed by stretching of the stretchable material. The outer surface 59 of the floating liner 50 may be in frictional engagement with the inner padding 15 in response to the rotational impact such that at least part of the rotational energy is dissipated by friction between the inner padding 15 and the outer surface 59 of the floating liner 50, the outer surface 59 of the floating liner 50 having a coefficient of friction with the inner padding 15 of at least 0.2 measured according to ASTM G115-10.
Several variants of the floating liner 50 are possible in other embodiments. For example, in some embodiments, in order to better manage the energy absorption of the floating liner 50, a hybrid structure can be considered where different components have different functions. For example, it is possible to construct the floating liner 50 from two different materials, one being more energy absorbing that the other when the floating liner 50 is stretched. This could provide a more economical product where the parts of the floating liner 50 that do not stretch during a rotational impact use less expensive material, such as non-stretchable fabric, while the remainder is made up of stretchable and energy absorbing material. In one particular example, the top portion 65 could be made of non-stretchable material.
Instead of using non-stretchable material, other types of materials can be used to provide desirable attributes to the floating liner 50, such as comfort materials that have a high resiliency (those materials are stretchable but do not absorb much energy) and porous materials to absorb perspiration, among others.
In another possible variant, the friction between the floating liner 50 and the inner padding 15 can be selectively controlled by providing between these components a material that has a particular coefficient of friction. That material can be applied as a series of patches to the floating liner 50 or to the inner pad 15 such as to achieve the desired degree of friction.
In another embodiment, the inner surface of the floating liner 50 which faces the inner padding 15 may be provided with a series of projections that fit in corresponding recesses made on the inner padding 15. In this case, the projections are generally semi-spherical and are integrally formed with the remainder of the floating liner 50. The purpose of the projections is to create an interface with the inner padding 15 in which the resistance to movement is increased in order to increase the energy uptake. The mating relationship between the projections and the corresponding mating recesses in the inner padding 15 would require more energy to move the floating liner 50 with relation to the inner padding 15. More energy is required since the projections must be deformed sufficiently to move out of the corresponding recesses. The number, shape and size of the projections can vary to a great extent in various embodiments. A larger number of projections will increase the holding force and thus require a stronger effort to initiate the movement between the floating liner 50 and the inner padding 15. Larger projections will have the same effect since more material compression will be required for the projections to clear their respective recesses.
In order to allow for adjustability of the sports helmet 10, the recesses on the inner padding 15 can be made sufficiently large such that they register with respective projections in a number of different positions of the inner pad segments. In such cases, elongated recesses can be used. Each elongated recess is oriented such that it extends along the direction in which the inner pad segment moves when the helmet size is adjusted. The width of the recess generally matches the diameter of the projection. As the inner pad position changes when adjustments to the helmet size are made, the longitudinal position of the projection in the recess changes.
The reverse arrangement can also be considered, where projections are provided on the inner padding 15 and fit in corresponding recesses on the floating liner 50.
The attachment of the floating liner 50 to the sports helmet 10 is such as to enable the relative motion to occur during a rotational impact. This relative motion is made possible by the ability of the floating liner 50 to move over the inner padding 15 and also by the ability of the floating liner 50 to stretch. As discussed above, the floating liner 50 is connected to the outer shell 12 or the inner padding 15 near the lower edge of the sports helmet 10, leaving the upper part of floating liner 50 freely resting on the inner padding 15. Such a construction thus provides an interface between the floating liner 50 and the inner padding 15 that is fastener-free over a surface area of a desired extent over which the free-floating interaction is desirable.
By “fastener-free” interface is meant an interface that does not contain any mechanical or adhesive fastener that could severely impede the ability of the two opposing surfaces that define the interface to move one with relation to the other.
The fastener-free interface area is also advantageous when the sports helmet 10 is adjustable to better fit the head 11 of the wearer. This fastener-free interface thus allows the segments or branches that make up the inner padding 15 to be moved, such as to provide adjustability to several different positions without impeding the ability of the floating liner 50 to move with relation to the inner padding 15. As indicated earlier, the sports helmet 10 is adjustable along its longitudinal axis FBA by allowing the front and the rear outer shell members 22, 24 to move one relatively to the other. As a result of this movement, the inner pad members of the inner padding 15 also move. Accordingly, each adjustment position of the outer shell 12 corresponds to a particular position of the inner pad members 15A, 15B, 15C, 15D, 15E. As the outer shell members 22, 24 are displaced along the longitudinal axis, the inner pad members 15A, 15B, 15C, 15D, 15E are also moved one with relation to the other such as to alter the void volume of the sports helmet 10.
By using a fastener-less interface between the inner padding 15 and the floating liner 50, the inner pad members 15A, 15B, 15C, 15D, 15E can move during an adjustment operation without interfering with the floating liner 50.
Note that if necessary to use some sort of fastener to retain the floating liner 50 to the upper part of the sports helmet 10, a possible arrangement can be considered where the floating liner 50 is connected to a component other than the inner padding 15. This component can be the outer shell 12. This connection can be independent from the inner padding 15 such as to allow the inner pad members 15A, 15B, 15C, 15D, 15E to move relative to one another without interfering with the floating liner 50. In a specific example (not shown in the drawings) the inner padding 15 is provided with apertures through which the connections can reach the outer shell 12. The apertures are large enough such as to provide a range of motion for the inner pad members 15A, 15B, 15C, 15D, 15E for adjustability purposes. An example of a connection is an elastic strap that connects the floating liner 50 to the outer shell 12. The strap extends to a slot through the inner padding 15 such that the inner pad members 15A, 15B, 15C, 15D, 15E can move without interfering with the strap. Note that in this example of implementation, the interface between the floating liner 50 and the inner padding 15 is still considered to be fastener-less since no fastener exists between the floating liner 50 and the inner padding 15 that fixes the floating liner 50 relative to the inner padding 15.
The floating liner 50 may be elastic and self-standing. The floating liner 50 is self-standing in that it stands on its own upwardly within the sports helmet 10 and maintains its dome shape for receiving the wearer's head 11 when the sports helmet 10 is not being worn (i.e., when the wearer's head 11 is not received in the sports helmet 10). The dome shape of the floating liner 50 is maintained without the need of suspending the floating liner 50 from the inner padding 15 or from the outer shell 12, such as by using a fastener located near the apex 500 or any other suspension mechanism.
While being elastic, the floating liner 50 has sufficient rigidity to make it self-standing. The rigidity of the floating liner 50 is sufficient to prevent the floating liner 50 from falling down outside of the cavity 13 of the sports helmet 10 under its own weight when the wearer's head 11 is not received in the sports helmet 10.
The rigidity of the floating liner 50 and its ability to be self-standing may be achieved in various ways and is a function of the floating liner's material and structure. For example, in this embodiment, to increase the rigidity of its structure, the segments of the floating liner 50 are provided with a plurality of rigidifying zones 851-85R spaced apart from one another by a plurality of flexing zones 861-86F such that adjacent rigidifying zones 85i, 85j are more rigid than a flexing zone 86i in between them. The rigidifying zones 851-85R contribute to maintain the shape of the floating liner 50 by providing additional support. The combination of the flexing zones 861-86F and the rigidifying zones 851-85R is selected to provide simultaneously flexibility and a degree of rigidity to cause the floating liner 50 to self-support itself.
In this embodiment, the rigidifying zones 85i, 85j are more rigid than the flexing zones 861-86F because they are thicker than the flexing zones 861-86F. More particularly, in this embodiment, the rigidifying zones 851-85R comprise the padded areas 1851-185R and the ridges 142 of the floating liner 50 where additional material is provided. The rigidifying zones 85i, 85j may be made more rigid than the flexing zones 861-86F in other ways in other embodiments (e.g., by being made of material having a greater modulus of elasticity and/or a greater hardness than material of the flexing zones 861-86F).
Although it is sufficiently rigid to self-stand within the cavity 13 of the sports helmet 10, the floating liner 50 may also be sufficiently flexible to be manually pulled away from the inner padding 15. In this example, this may facilitate cleaning of the inner surface of the inner padding 15 and/or the outer surface 61 of the floating liner 50. More particularly, in this embodiment, the floating liner 50 can be manually pulled away from the inner padding 15 such that at least part of the floating liner 50 extends outside of the cavity 13 of the sports helmet 10. In this example, this may allow the floating liner 50 to acquire an inverted dome shape in which its outer surface 61 is generally concave (instead of generally convex when the floating liner 50 has its dome shape within the sports helmet 10) and its inner surface 59 is generally convex (instead of generally concave when the floating liner 50 has its dome shape within the sports helmet 10). In this case, the rigidity of the floating liner 50 allows it to be self-standing even in its inverted dome shape.
While in this embodiment the floating liner 50 is implemented in a particular way, the floating liner 50 may be implemented in various other ways in other embodiments. For example, in other embodiments, the floating liner 50 may be made of materials other than those discussed herein, may have a shape different than that discussed herein, and/or may be located elsewhere between the external surface 18 and the internal surface 20 of the helmet 10 (e.g., between the outer shell 12 and the inner padding 15).
Moreover, although in embodiments considered above the rotational impact protection device is implemented by the floating liner 50, the rotational impact protection device may be implemented in various other ways in other embodiments. For example, in other embodiments, the inner padding 15 may implement the rotational impact protection device by allowing an angular movement of the external surface 18 of the helmet 10 relative to the inner surface 34 of the inner padding 15 in response to a rotational impact to absorb rotational energy from the rotational impact. For instance, in some embodiments, each of the inner pad members 15A, 15B, 15C, 15D, 15E may comprise elastically shearable material which can shear in response to a rotational impact to allow an angular movement of the external surface 18 of the helmet 10 relative to the inner surface 34 of the inner padding 15 (e.g., each of the inner pad members 15A, 15B, 15C, 15D, 15E of the inner padding 15 may comprise a shear pad). In other embodiments, the inner pad members 15A, 15B, 15C, 15D, 15E of the inner padding 15 may not necessarily themselves shear, but may be mounted to an elastically shearable layer disposed between the outer shell 12 and the inner padding 15. For example, the shearable material of the inner padding 15 and/or the shearable layer may be a gel, an elastomer, or any other suitable material that can elastically shear.
Any feature of any embodiment discussed herein may be combined with any feature of any other embodiment discussed herein in some examples of implementation.
Various embodiments and examples have been presented for the purpose of describing, but not limiting, the invention. Various modifications and enhancements will become apparent to those of ordinary skill in the art and are within the scope of the invention, which is defined by the appended claims.
This application claims priority to U.S. Provisional Application No. 61/512,266 filed on Jul. 27, 2011 and U.S. Provisional Application No. 61/587,040 filed on Jan. 16, 2012, the contents of which are incorporated herein by reference in their entirety.
Number | Date | Country | |
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61512266 | Jul 2011 | US | |
61587040 | Jan 2012 | US |
Number | Date | Country | |
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Parent | 13560546 | Jul 2012 | US |
Child | 14139049 | US |