The present application relates to sport helmets, such as bicycle helmets.
Bicycle helmets have become ubiquitous for cycling activities, and other sports. In road and urban bicycle riding, one specific helmet construction is commonly used, that consisting of the foam inner liner with an outer shell. The inner liner forms the body of the helmet in terms of volume and structural integrity. The inner liner is typically made of a structural foam material such as expanded polystyrene. An outer shell covers the liner and defines the smooth, aerodynamic and/or decorative exposed outer surface of the helmet. The outer shell and liner may commonly be co-molded, and additional structural and attachment components may be present. Other components include the attachment system inside the outer shell, by which the helmet is secured to the user's head. The above-referred configuration is quite convenient in terms of providing suitable head protection, while being lightweight.
However, while protecting the head from some form of traumatic injuries such as skull fractures and skin wounds, helmets may leave the wearer exposed to some other forms of trauma, such as concussions. For example, angled impacts on one's head may result in a concussion, in spite of the presence of a helmet. Moreover, the liner is a stiff component that may be uncomfortable to a wearer. Accordingly, some technologies have been developed to assist in absorbing shocks, such as that described in U.S. Pat. No. 8,578,520. It describes the presence of an attachment device that accommodates the wearer's head. The attachment device is a low-friction layer that creates a relative motion between the inner liner and the skull, at a point of angled contact. Hence, rotational energy is directed away from the brain, so as to reduce the strain in the brain tissue at an impact.
Therefore, it is an aim of the present disclosure to provide a helmet that addresses issues associated with the prior art.
In accordance with an aspect, there is provided a helmet comprising: at least an inner liner forming a body of the helmet, the inner liner having a concave inner surface defining a cavity configured for receiving a wearer's head; a plurality of slippage pads disposed at selected locations on the concave inner surface and connected to the inner liner, the slippage pads having an elongated shape with a length and a width, the length being greater than the width, the slippage pads each defining a number of integrally connected side-by-side tubes each having an opening adapted to be oriented toward the wearer's head, the openings aligned longitudinally along the length of the slippage pads; a plurality of projecting cushioning pads disposed adjacent to the slippage pads, and having a greater height than the slippage pads and exhibiting a greater deformability than the slippage pads; and an attachment system to attach the helmet to the wearer's head.
Referring to the drawings, and more particularly to
The helmet 10 has a generally hemispherical shape formed by an inner liner 12 and an outer shell 13. By its hemispherical shape, the helmet 10 has an inner concave surface and outer convex surface, with the top and side of the wearer's head being received in the inner concavity. The inner liner 12 is typically made of foam (e.g., expanded polystyrene or the like) and constitutes the major component of the helmet 10 in terms of volume and energy absorption capability: it is the structure of the helmet 10. Moreover, the foam is of the type being generally rigid and hence providing the structural integrity to the helmet 10, in terms of maintaining its shape. In other words, the foam liner is not of the resilient type that is supported by a rigid shell, but rather of the type that is the main structural component of the helmet 10. It is by the combination of the attachment system 11 and the inner liner 12 that the helmet 10 remains attached to the wearer's head. The inner liner 12 covers an upper portion of the head, and the attachment system 11 prevents the inner liner 12 from being pulled off (in translation). However, some play may be present between the head of the wearer and the inner liner 12, due to the somewhat complementary spherical shapes. The play may enable absorption of angled impacts on the helmet.
The outer shell 13 is integrally connected to the inner liner 12 and forms the major portion of the exposed convex surface of the helmet 10. The integral connection may be achieved by way of adhesives or co-molding (i.e., molding of the inner liner 12 with the outer shell 13 positioned in the mold cavity beforehand). The outer shell 13 is made of a plastic layer, such as polycarbonate or the like, as a possibility. The outer shell 13 defines the smooth and decorative outer surface of the helmet 10. Other components may be present, such as a cage, as described in U.S. patent application Ser. No. 14/049,375, the contents of which are incorporated herein by reference. Also, the helmet 10 may have an inner liner 12, but no other shell 13, or multiple shell segments, among other possible variants.
Referring to
Moreover, the slippage pads 20 may allow a relative slippage motion between the surface of the inner liner 12 and the head of the wearer, in quasi-translational manner. As the surface of the inner liner 12 is concave, it is not fully flat. Hence, the movement is not purely translational, but close to a translation, explaining the use of the expression quasi-translational, as well as the expression slip plane system, as non-flat planes of the inner liner 12 and of the skull of the wearer may move relative to one another. The movement may also be described as a sliding movement of a part of the slippage pads 20 relative to the concave surface of the inner liner 12. It is the resistance of this sliding movement that allows absorption of angled impacts on the helmet 10.
Referring to
The openings 21A may have an elongated shape with a length of 15 mm±5 mm and a width of 5 mm±3 mm. In the embodiment shown, the common wall 22 between the adjacent openings 21A has a minimum longitudinal dimension (dimension taken along the length of the pad 20, shown as being along axis X) of 4 mm±2 mm. In an embodiment, the minimum longitudinal dimension of the common wall 22 is between 10% to 20%, inclusively of the length of the slippage pad 20 of
There may be more than two openings 21A per slippage pad 20 in other embodiments. The openings 21A may be evenly distributed in said slippage pad 20, although this may be different in other embodiments (non even distribution). The dimensions of the openings 21A may be defined as a ratio of their dimensions with a corresponding dimensions of the slippage pad 20. For instance, in an embodiment, a ratio of the sum of the length of the openings 21A over the length of the slippage pad 20 is 70%±20%. A ratio of the width of the openings 21A over the width of the slippage pad 20 may range between 25% and 40%—the width being along axis Y. Other ratios may be contemplated in other embodiments. As shown in
The slippage pad 20 of
A bottom portion of the slippage pad 20 may be received in a recess defined within the inner liner 12. At least part of the bottom portion of the slippage pad 20 may be adhesively bonded to the inner liner 12 or cushioning pad 15. For instance, bonding zones are located at the bottommost portion of the slippage pad 20 only. This may allow the remainder of the bottom portion of the slippage pad 20—i.e., one that is unattached to the inner liner 12—just as the top portion of the slippage pad 20, to deform “laterally”, stretch, buckle, distort, and/or shear when an angled impact (e.g. angled force or tangential force relative to a longitudinal axis of the slippage pad 20) is made on the helmet 10, even though the bottom portion may be in a recess and surrounded by the material of the inner liner 12. In other words, the peripheral surface of the bottom portion, where it is not adhesively bonded or physically attached to the liner 12, may move toward and away from the recess wall when the slippage pad 20 deforms. Other ways for securing the slippage pads 20 to the inner liner 12 or cushioning pad 15 may also be contemplated, such as mechanical interlock due to interlocking shapes of the slippage pads 20 and a recess, for instance.
The slippage pads 20 may be described as having an elongated shape with a length and a width, the length being greater than the width, the slippage pads 20 each defining a number of integrally connected side-by-side tubes each having an opening adapted to be oriented toward the wearer's head, the openings aligned longitudinally along the length of the slippage pads. In a variant, the slippage pads 20 may also be described as defining blocks of resilient material, the blocks having an elongated shape with a length and a width, the length being greater than the width, the blocks each having a number of integrally connected side-by-side tubes each having an opening adapted to be oriented toward the wearer's head, the openings aligned longitudinally along the length of the blocks, the openings being empty. In a variant, the slippage pads 20 may be described as defining blocks of resilient material, the blocks being monoblock pieces made of a single material, the blocks having an elongated shape with a length and a width, the length being greater than the width, the blocks each having a number of integrally connected side-by-side tubes each having an opening adapted to be oriented toward the wearer's head, the openings aligned longitudinally along the length of the blocks.
Referring to
As observed from
In a variant, a deformability of the cushioning pads 30 is greater than that of the slippage pads 20. More specifically, the cushioning pads 30 may exhibit lesser resistance to compression than the slippage pad 20. In another embodiment, in spite of a compression due to the contact with the head, the height of the cushioning pad 30 may remain greater than that of the slippage pad 20. The cushioning pads 30 are typically made of a closed cell foam, such as expanded polypropylene or polyethylene. Open cell foams may also be used. The cushioning pads 30 may also be made of a combination or materials, with a fabric or felt for the interface with the cranium. In an embodiment, the cushioning pad 15 has greater flexibility than the cushioning pads 30. An exemplary hardness for the cushioning pads 30 is of 10 for a type A durometer.
The cushioning pads 30 may have different shapes. In the embodiment of
The cushioning pads 30 may be removably connected to the inner liner 12, such as, by Velcro™. The cushioning pads 30 may also be connected in other ways or in supplemental ways to the helmet 10 in other embodiments, such as by adhesive bonding or other means for permanently and/or releasably connecting the cushioning pads 30 to the inner liner 12.
In operation, when an angled impact is made on the helmet 10, depending on the magnitude of an impact, the slippage pads 20, in contact with various discrete locations of the wearer's head, allow displacement of the inner liner 12 relative to the wearer's head, by deformation of the slippage pads 20, while the slippage pads 20 remain bonded to the inner liner 12. While the slippage pads 20 are deforming, for instance “laterally”, the slippage pads 20 may compress to absorb energy from the angled impact. In case of a linear impact, the cushioning pads 30 may compress until the cranium contacts the slippage pads 20. This is permissible due to the greater height of the cushioning pads 30 than that of the slippage pads 20. Accordingly, a dual reaction is permissible, based on the nature of the impact.
In another variant of operation, when an angled impact is made on the helmet 10, again depending on the magnitude of an impact, the cushioning pads 30 may first compress until the cranium contacts the slippage pads 20. Then, the slippage pads 20, in contact with various discrete locations of the wearer's head, further allow displacement of the inner liner 12 relative to the wearer's head, by deformation of the slippage pads 20, while the slippage pads 20 remain bonded to the inner liner 12. This sequence is permissible due to the greater height of the cushioning pads 30 than that of the slippage pads 20.
If a recess wall is present, a gap may be created between a recess wall and the peripheral surface of the bottom portion of the slippage pad 20. Thus, at least part of the peripheral surface of the bottom portion moves away from the recess wall while an opposite part of the peripheral surface of the bottom portion is compressed against the recess wall as a result of the deformation of the slippage pad 20. The bottom portion of the slippage pad 20 may have a size and shape corresponding to the shape and size of the recess in which it is received, this may be different in other embodiments. For instance, the recess may be larger than the bottom portion of the slippage pad 20, such that only the bottommost portion of the slippage pad 20 that is secured to the inner liner 12 contacts the recess wall, when the slippage pad 20 is in an non-deformed state. This may allow the bottom portion to expand laterally when the slippage pad 20 is compressed longitudinally, which may increase the amount of energy absorption due to angled impact, for instance. In other cases, the recess may be smaller than the bottom portion of the slippage pad 20, such that the bottom portion does not entirely recede within the recess.
Referring to
As shown, the slippage pads 20 and projecting cushioning pads 30 are connected to the inner liner 12. The slippage pads 20 and projecting cushioning pads 30 may be connected to the inner liner 12 by adhesive bonding. Other ways to secure the slippage pads 20 to the inner liner 12 may be contemplated in other embodiments, such as co-molding, mechanical interlocking or via mechanical connectors, such as mechanical fasteners. As shown, the slippage pads 20 and projecting cushioning pads 30 are directly connected to the inner liner 12. In other embodiments, the slippage pads 20 may be connected to an intermediary piece of material, such as a web, or a layer of material such as a layer of woven material, interconnecting the slippage pads 20 and projecting cushioning pads 30 together. This may facilitate handling of the slippage pads 20 and projecting cushioning pads 30 as a cluster of slippage pads 20 and projecting cushioning pads 30 during manufacturing and/or assembly of the helmet 10, amongst other things.
In an embodiment, the slippage pads 20 have a base portion Z1 along axis Z (
The slippage pad 20 has the head contacting portion Z2 that protrudes from the concave inner surface of the inner liner 12, out from the recess if present. The recesses may allow the slippage pads 20 to have a greater overall thickness, which may increase the energy absorption of the slippage pads 20, as opposed to embodiments where the inner liner 12 has no recess receiving the slippage pads 20. The recesses may thus allow the use of thicker slippage pads 20 while concurrently keeping the helmet 10 “compact”, in that the inner liner 12 may still remain close to the wearer's head when the helmet 10 is worn. This may contribute to having a helmet 10 that appears less bulky on the wearer's head without compromising on the thickness of the slippage pads 20 between the wearer's head and the inner liner 12. In embodiments where the recesses are present, a ratio of a recess depth over the thickness of the slippage pads 20 is no more than 1:2, (i.e., dimension of Z1 along axis Z over Z1+Z2). In some cases, such ratio may be no more than 1:3, and in some cases no more than 1:4. Other ratios are possible in other embodiments.
An angled impact on the helmet 10 having such slippage pads 20 projecting cushioning pads 30 may result in geometrical deformation of the tubes 21 relative to the wearer's head. In other words, an angled impact on the helmet 10 may result in a movement resulting from deformation of the tubes 21 and of the projecting cushioning pads 30, and relative movement of the head contacting surface of the slippage pads 20 with respect to the inner liner 12. Some or all of the slippage pads 20 and projecting cushioning pads 30 may be subjected to local deformation independently of how the other slippage pads 20 and projecting cushioning pads 30 react. The common reaction of the slippage pads 20, which may correspond to the sum of deformations of the slippage pads 20 disposed at selected locations on the inner liner 12 of the helmet 10, when an angled impact on the helmet 10 is made, may provide impact energy absorption via geometrical deformation of the slippage pads 20. As such, the amount of impact energy transmitted to the wearer's head may be less than that transmitted to the wearer's head when the slippage pads 20 are absent from the helmet 10, in some embodiments. The deformation of the slippage pads 20, as mentioned previously, may be in the form of flexion, compression, distortion, shearing and/or buckling of the tubes 21.
The helmet 10 defines a frontal portion for covering at least partially a frontal region of the wearer's head, a rear portion for covering a rear region of the head, opposite lateral portions for covering opposite lateral regions of the head, and a top portion for covering a top region of the head. With continued reference to
Additionally, the at least one slippage pad 20 in the opposite lateral portions of the helmet 10 are located on the inner liner 12 at locations that intersect with the frontal plane Y-Y of the helmet 10. The at least two slippage pads 20 located in the rear portion of the helmet 10 are longitudinally oriented such that their respective longitudinal projections are transverse to the longitudinal projections of the slippage pads 20 of the frontal and top portions of the helmet 10. The individual position of the slippage pads 20 and their relative positions may be different in other embodiments.
Referring to
In
The present application claims the priority of U.S. patent application No. 63/219,539, filed on Jul. 8, 2021, and of U.S. patent application No. 63/220,741, filed on Jul. 12, 2021, and of U.S. patent application No. 63/249,059, filed on Sep. 28, 2021, the contents of all of which are incorporated herein by reference.
Number | Date | Country | |
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63219539 | Jul 2021 | US | |
63220741 | Jul 2021 | US | |
63249059 | Sep 2021 | US |