Patent Description:
One or more embodiments of the present invention generally relate to safety equipment, and more particularly for example, to protective helmets that protect the human head against repetitive impacts, moderate impacts and severe impacts so as to significantly reduce the likelihood of both translational and rotational brain injury and concussions.

Action sports (e.g., skateboarding, snowboarding, bicycle motocross (BMX), downhill mountain biking, and the like), motorsports (e.g., off-road and on-road motorcycle riding and racing) and traditional contact sports (e.g., football and hockey) continue to grow at a significant pace throughout the world as each of these sports expands into wider participant demographics. While technology and sophisticated training regimes continue to improve the performance capabilities for such athletes/participants, the risk of injury attendant to these activities also increases. Current "state of the art" helmets are not keeping pace with the evolution of sports and the capabilities of athletes. At the same time, science is providing alarming data related to the traumatic effects of both repetitive but moderate, and severe impacts to the head. While concussions are at the forefront of current concerns, rotational brain injuries from the same concussive impacts are no less of a concern, and in fact, are potentially more troublesome.

<CIT> discloses a safety helmet, wherein the inner and outer liners thereof are coupled to each other so as to form an internal subassembly by the use of a plurality of resilient structures.

<CIT> discloses a protective helmet. According to an embodiment, a head-side insert comprises an elevation which projects into the region of a shell-side insert. The elevation is surrounded by a damping means which is compressed during a blow from the front, while the head side insert rotates backwards together with the outer shell.

<CIT> discloses a helmet including a shell and a shock absorbing liner that is split into an outer liner and an inner liner. The outer liner and the inner liner have respective dents or recesses, opposite to each other. In each space formed by the corresponding dents is disposed a layer of an absorbent elastic body stuck to the outer liner and the inner liner.

<CIT> discloses a head protection. There is a shell and two layers of liner material. A device is placed therebetween. The device comprises a liquid or gel like material in a bladder that flexible inner and outer walls to float or slide relative to one another.

Omnidirectional impact energy management systems are provided for protective helmets that can significantly reduce both rotational and linear forces generated from impacts to the helmets over a broad spectrum of energy levels.

Embodiments enable the production of hard-shelled safety helmets that can provide a controlled internal omnidirectional relative displacement capability, including relative rotation and translation, between the internal components thereof. The systems enhance modern helmet designs for the improved safety and well-being of athletes and recreational participants in sporting activities in the event of any type of impact to the wearer's head. These designs specifically address, among other things, the management, control, and reduction of angular acceleration forces, while simultaneously reducing linear impact forces acting on the wearer's head during such impacts.

According to the present invention, there is provided a helmet according to claim <NUM>.

In accordance with one or more embodiments of this disclosure, omnidirectional impact energy management systems for helmets are provided that can significantly reduce both rotational and linear forces generated from impacts imparted to the helmets. The systems enable a controlled internal omnidirectional relative displacement capability, including relative rotational and translational movement, between the internal components of a hard shelled safety helmet.

One or more embodiments disclosed herein are particularly well suited to helmets that can provide improved protection from both potentially catastrophic impacts and repetitive impacts of varying force that, while not causing acute brain injury, can cause cumulative harm. The problem of cumulative brain injury, i.e., Second Impact Syndrome (SIS), is increasingly recognized as a serious problem in certain sports, such as American football, where much of the force of non-catastrophic contact is transferred to the head of the wearer. In various example embodiments, helmets are configured with dampers of specific flex and compression characteristics to manage a wide range of repetitive and severe impacts from all directions, thus addressing the multitude of different risks associated with diverse sports, such as football, baseball, bicycle riding, motorcycle riding, skateboarding, rock climbing, hockey, snowboarding, snow skiing, auto racing, and the like.

Head injuries result from two types of mechanical forces - contact and non-contact. Contact injuries arise when the head strikes or is struck by another object. Non-contact injuries are occasioned by cranial accelerations or decelerations caused by forces acting on the head other than through contact with another object, such as whiplash-induced forces. Two types of cranial acceleration are recognized, which can act separately or in combination with each other. "Translational" acceleration occurs when the brain's center of gravity (CG), located approximately at the pineal gland, moves in a generally straight line. "Rotational" or angular acceleration occurs when the head turns about its CG without linear movement of the CG.

Translational accelerations/decelerations can result in so-called "coup" and "contre-coup" head injuries that respectively occur directly under the site of impact with an object and on the side of the head opposite the area that was impacted. By contrast, studies of the biomechanics of brain injury have established that forces applied to the head which result in a rotation of the brain about its CG cause diffuse brain injuries. It is this type of movement that is responsible for subdural hematomas and diffuse axonal injury (DAI), one of the most devastating types of traumatic brain injury.

<FIG> is a cross-sectional view of an example of a helmetuseful for understanding the invention. The helmet of <FIG> includes at least two layers and is designed to absorb both translational and rotational forces. Helmet <NUM> of <FIG> includes an outer liner <NUM>, an inner liner <NUM>, a substrate <NUM>, isolation damper <NUM>, and insert <NUM>.

The outer liner <NUM> may be disposed of or contained within an outer shell (not shown) of the helmet <NUM>. The outer shell may be a relatively hard outer shell (i.e., harder than the liners of the helmet <NUM>) and may be made from, for example, polycarbonate, ABS plastic, PVC plastic, nylon, fiberglass, carbon fiber, carbon fiber reinforced plastic, other plastics, wood, metals, or other suitable materials. The outer shell may contain the various components highlighted in <FIG>. The outer liner <NUM> may be bonded to the outer shell, attached to the outer shell through mechanical fasteners such as screws, rivets, and mechanical attachment features on one or both of the outer shell and the outer liner <NUM>, and/or placed inside the outer shell and allowed to translate and/or rotate.

The outer liner <NUM> may be disposed between the outer shell and any inner liners, dampers, or other components. The outer liner <NUM> may be formed of any suitable material, including energy absorbing materials of the types commonly used in the industry, such as expanded polystyrene (EPS) or expanded polypropylene (EPP).

In addition to the properties of the material of the outer liner <NUM>, the outer liner <NUM> may also include various features that may absorb force. For example the outer liner <NUM> may include the lug <NUM>. The lug <NUM> may be a protrusion from a side of the outer liner <NUM>. The lug <NUM> may be on the outside (i.e., the side closer to the outer shell) or may be on the inside (i.e., the side closer to the inner liner <NUM>) of the outer liner <NUM>. The lug <NUM> may deform when subjected to a force. The force may be an axial force, a lateral force, a rotational motion, another type of force, or a combination of such forces. The lug <NUM> may be molded from the same material as the outer liner <NUM> and may be a part of the outer liner <NUM> (that is, for example, manufactured from the same mold). In <FIG>, the inner liner <NUM> may include a surface for the lug <NUM> to contact. The lug <NUM> may contact the inner liner <NUM> or there may be, when the helmet <NUM> is in a normal operating condition or a resting position (i.e., not absorbing a force), a space separating the lug <NUM> from the inner liner <NUM>. The helmet may smoothly ramp up resistance force of the liners by allowing the lug <NUM> to contact or engage the inner liner <NUM> at certain stages of deformation of the inner liner <NUM>. Accordingly, the outer liner <NUM> or the inner liner <NUM> may include a plurality of lugs, such as more than <NUM>, more than <NUM>, more than <NUM>, more than <NUM>, or more than <NUM> lugs. The lugs may all be the same height, or the various lugs may be a plurality of different heights. When the lugs may be one of a plurality of different heights, the height, the material, and the quantity of lugs at any specific height may be selected to allow the resistance force of the liners to smoothly ramp. Additionally, while the inner liner <NUM> of <FIG> may not include detents or cup-like features to contact and/or locate the lug <NUM>, the inner liner <NUM> may include such features or there may be a separate layer with such features.

The inner liner <NUM> may be disposed of or contained within the outer liner <NUM>. The inner liner <NUM> may, similar to the outer liner <NUM>, be formed of any suitable material, including energy absorbing materials of the types commonly used in the industry, such as expanded polystyrene (EPS) or expanded polypropylene (EPP). The inner liner <NUM> may also be bonded, attached via mechanical fasteners such as screws, rivets, and mechanical attachment features, and/or placed inside the outer liner <NUM> and allowed to translate and/or rotate. The inner liner <NUM> may also be attached to the outer shell.

The inner liner <NUM> may include a lug or a plurality of lugs. The lugs may be similar to the lug <NUM>. When the inner liner <NUM> includes a lug or a plurality of lugs, a component the lug <NUM> may be configured to contact, such as the outer liner <NUM>, the outer shell, or an intermediate liner, may not include detents or cup-like features to contact and/or locate the lug. Such components may include such features or there may be a separate layer with such features.

The substrate <NUM> may be an intermediate layer between the outer liner <NUM> and the inner liner <NUM>. The substrate <NUM> may be a support for the isolation damper <NUM> or a plurality of isolation dampers. The isolation damper <NUM> may be an elastomeric structure and be designed to absorb shock and/or allow controlled movement of the inner liner <NUM> relative to the outer liner <NUM>. The isolation damper <NUM> may allow the inner liner <NUM> to translate and/or rotate relative to the outer liner <NUM>. Thus, the isolation damper <NUM> may allow omnidirectional movement of the inner liner <NUM> relative to the outer liner <NUM>, or vice versa. Such allowed movement may better absorb translation and/or rotational movement of a helmet wearer's head and thus offer improved protection. The isolation damper <NUM> may be formed of a wide variety of elastomeric materials, including MCU (micro-cellular urethane), EPU, natural rubber, synthetic rubbers, foamed elastomers of various chemical constituents, solid cast elastomers of various chemical constituents, encased liquids, gels or gasses providing flexible structures, and any flexible assembly of any other kind that will provide the desired degree of omnidirectional movement.

Additionally, the isolation damper <NUM> may include one or more protrusions. The protrusions may be optional features. The protrusions may include features to, for example, absorb shock or couple various components together. Accordingly, the isolation damper <NUM> may also include conical, spherical, partially spherical or conical, rectangular, or other such geometric features. Features and/or with corresponding geometries (e.g., configured to receive a conical or spherical shape) may be fitted into the corresponding liners or other components that may receive the isolation damper <NUM>. The isolation damper <NUM> may not include protrusions and/or may be substantially cylindrical in profile.

The isolation damper <NUM> may be a part of an assembly to couple together the outer liner <NUM> and the inner liner <NUM>. The isolation damper <NUM> may, for example, mechanically couple to one or both of the outer liner <NUM> or the inner liner <NUM>. The isolation damper <NUM> may also, alternatively or in addition to, be coupled to the substrate <NUM>. The substrate <NUM> may then be coupled to one or both of the outer liner <NUM> and the inner liner <NUM>. In the helmet <NUM>, the isolation damper <NUM> may be coupled to the substrate <NUM> on one end and the outer liner <NUM> on another end. The substrate <NUM> may then be coupled to the inner liner <NUM>.

The outer liner <NUM> may include the insert <NUM> to receive the isolation damper <NUM>. The insert <NUM> may be a recess or aperture within the inner liner <NUM> and/or outer liner <NUM>. The recess or aperture may be fitted with inserts or cup-like inserts that locate and retain the isolation dampers <NUM> in place, provide additional support for the isolation dampers <NUM> within the liners, and/or help to manage and disburse impact forces acting on the helmet <NUM>. The insert <NUM> may be configured with any suitable geometry and can include flanges of appropriate sizes and/or shapes to distribute forces over a larger area of a corresponding one of the liners.

The insert(s) respectively disposed on the inner and/or outer liners <NUM> and/or <NUM> may be over-molded into the associated liner for attachment purposes, and may utilize a circumferential flange or multiple circumferential flanges in various sizes and configurations to help retain and distribute forces within the material of the associated liner.

The insert <NUM> may be held in the associated liner by, for example, friction, or alternatively, by any other suitable means, including adhesives, heat bonding and/or welding, and similarly, the respective ends of the isolation damper <NUM> may be held in the corresponding insert <NUM> by friction, or alternatively, be fixed in the insert <NUM> by any other suitable method or means. The insert <NUM> may be made of any suitable material, including thermosetting or thermoforming plastics, such as acrylonitrile butadiene styrene (ABS), polyvinylchloride (PVC), polyurethane (PU), polycarbonates, nylon, various alloys of metals, and the like.

In addition to impact absorbing features, the helmet <NUM> may also include features to improve comfort. For example, the inner liner <NUM> may include a vent <NUM> to improve ventilation within the helmet <NUM>. The vent <NUM> may be a cutout of various geometries within the inner liner <NUM> to allow air to flow through the inner liner <NUM>. Vents may also be present on the outer liner, on intermediate liners, or on other components within the helmet <NUM>.

Referring back to the substrate <NUM>, the substrate <NUM> may be coupled to the inner liner <NUM> through various different methods and components. <FIG> illustrates one such method. <FIG> is another view of the example helmet of <FIG>. The helmet <NUM> in <FIG> includes the outer liner <NUM>, the inner liner <NUM>, the substrate <NUM>, isolation damper <NUM>, and attachment feature <NUM>. The various components in <FIG> may be similar to their respective components in <FIG>.

In <FIG>, the outer liner <NUM> may be shown in an unfolded configuration. The unfolded configuration may be similar to or the same as how the outer liner <NUM> is manufactured. The outer liner <NUM> may be manufactured in a substantially flat pattern. The outer liner <NUM>, as well as other components described herein, may include cutouts to allow the outer liner <NUM> and other components to fold into a cup-like shape that would substantially conform to a wearer's head.

In addition to the components of <FIG> that is also included in <FIG>, the helmet <NUM> in <FIG> also includes the attachment feature <NUM>. The attachment feature <NUM> may be a pin, a bolt, a nut configured to engage a bolt, a stand-off, an adhesive, welding, tape or Velcro, or other suitable fastener. In <FIG>, the attachment feature <NUM> may be a pin that may be inserted into the inner liner <NUM> to couple the substrate <NUM> to the inner liner <NUM>. The portion of the inner liner <NUM> that may receive the pin may include features to prevent the pin from easily backing out. For example, the inner liner <NUM> may include a hole configured to receive the pin and the hole may include a raised surface around at least a portion of the circumference of the hole. The raised surface may then contact the pin or features on the pin designed to receive the raised surface and may prevent the pin from backing out of the hole. The pin may instead include such features instead of the hole or the hole and pin may both include such features.

The attachment feature <NUM> may also be other features. For example, the attachment features <NUM> may be a stand-off or pin rising from the inner liner <NUM>. The substrate <NUM> may include a feature, such as a hole, that may receive the stand-off or pin. The stand-off or pin may then be inserted into the hole. The substrate <NUM> may include multiple holes and the inner liner <NUM> may include a corresponding number of stand-offs or pins. The substrate <NUM> may be stretched over the stand-offs or pins of the inner liner <NUM> during assembly. Once assembled, the substrate <NUM> may then be contained on the inner liner <NUM> through the shape of the substrate <NUM> alone, through fasteners such as screws, bolts, adhesives, or Velcro, or through a combination of multiple different methods of securing the substrate <NUM> to the inner liner <NUM>.

In addition to the liner and isolation damper configuration shown in <FIG> and <FIG>, various other configurations are possible to absorb impact. <FIG> show examples of such possible configurations. <FIG> are isometric and cross-sectional views of an impact absorbing system of a helmet useful for understanding the invention.

The impact absorbing system <NUM> includes an outer liner <NUM>, an inner liner <NUM>, a damper array <NUM>, and an outer shell <NUM>. The outer liner <NUM>, the inner liner <NUM>, and the outer shell <NUM> may be similar to their respective components described in <FIG>. The damper array <NUM> may include a first substrate <NUM>, dampers <NUM>, and a second substrate <NUM>. In <FIG>, the outer shell <NUM>, the outer liner <NUM>, and the second substrate <NUM> may be see-through to allow a better view of the dampers <NUM>.

The first substrate <NUM> may be a substrate made from the same material as the damper <NUM> or may be made from a different material. The first substrate may be harder than the damper <NUM> and may be, for example, polycarbonate, nylon, ABS plastic, PVC plastic, graphite, wood, metal, fiberglass, carbon fiber, Kevlar, or other suitable materials. Dampers <NUM> may be bonded or coupled to the first substrate <NUM>. For example, the dampers <NUM> may be bonded through an adhesive such as glue or through mechanical fasteners such as screws and push-pins. The first substrate <NUM> may aid in more evenly distributing force to the dampers <NUM> and/or to a substrate. Additionally, the first substrate <NUM> may also be coupled to the inner liner <NUM> through any appropriate way. For example, the first substrate <NUM> may be bonded to, molded, or fastened to the inner liner <NUM>.

The damper <NUM> may be an impact absorbing damper and may include any or all features of an isolation damper. The damper <NUM> may allow for omnidirectional movement of the inner liner <NUM> relative to the outer liner <NUM> and/or the outer shell <NUM> and may be of any appropriate material or geometry. Examples of suitable materials include MCU (micro-cellular urethane), EPU, natural rubber, synthetic rubbers, foamed elastomers of various chemical constituents, solid cast elastomers of various chemical constituents, encased liquids, gels or gasses providing flexible structures, and any flexible assembly of any other kind that will provide the desired degree of omnidirectional movement. The suitable materials may be isotropic or anisotropic.

The number of dampers <NUM> may be varied depending on the desired deformation characteristics. Including a plurality of dampers may more evenly distribution force across the dampers and, thus, reduce the likelihood of damage, such as tearing, permanent deformation, or other gouges, to the dampers <NUM>, the first substrate <NUM>, the second substrate <NUM>, the inner liner <NUM>, and/or the outer liner <NUM>.

The damper <NUM> may be of a geometry shaped to absorb shock. For example, the damper <NUM> may include a generally circular disk having a concave, e.g., generally spherical, recess disposed in a lower surface thereof, a correspondingly shaped convex protrusion extending from an upper surface thereof, and a flange extending around the circumference thereof. The damper <NUM> may include elongated cylindrical members.

Helmets may have all of the dampers be a certain shape or may include dampers with a plurality of different shapes, sizes, and/or materials. Different dampers designs may be used for specific applications and may be effectively "tuned" to manage the anticipated rotational and translational forces applied. The dampers may be variously configured to control the amount of rotational force that will cause displacement of the various liners of the helmet and may be configured such that they will tend to cause the inner liner <NUM> to return to its original position relative to the outer liner <NUM> after the force of an impact is removed from the helmet.

Limits or "stops" may be designed into and between the liners to prevent over-rotation or over-displacement between the layers during an impact incident. Other helmets may use other features of the helmet to act as stops. There may be dampers of various different heights or geometries. As the inner liner <NUM> compresses further from its normal resting position, relative to the outer shell <NUM>, the dampers may smoothly ramp up resistance force. For example, a certain helmet may only have <NUM>% of the damper engaging and offering resistance to movement at the normal resting position, but as the inner liner <NUM> compresses, additional dampers may engage and offer resistance to movement. The dampers <NUM> may also be of multiple different geometries to allow for the rate that their resistance force ramps up to vary depending on the amount of displacement of the inner liner <NUM>. For example, the dampers <NUM> may include grooves and flares for such purposes.

Additionally, the damper <NUM> may be coupled to the second substrate <NUM>. The second substrate <NUM> may be a substrate made from the same material as the first substrate <NUM> and/or the damper <NUM> or may be made from a different material. The second substrate <NUM> may be bonded or coupled to at least a portion of the dampers <NUM> and/or the outer liner <NUM>.

Certain helmets may not include one or both of the first substrate <NUM> or the second substrate <NUM>. In helmets with only one substrate instead of two substrates, the dampers may be coupled to the one substrate at one end and at least a portion of the dampers may contact or engage the liner at another end. In helmets without substrates, the dampers may be coupled to at least one of the liners or may be molded into at least one of the liners.

Various other impact absorbing systems are possible. <FIG> are isometric and cross-sectional views of another impact absorbing system of a helmet useful for understanding the invention. The impact absorbing system <NUM> of <FIG> includes an outer liner <NUM>, an inner liner <NUM>, and a damper array <NUM>. The damper array <NUM> may include a first substrate <NUM>, ball <NUM>, housings <NUM>, and a second substrate <NUM>. In <FIG>, the outer liner <NUM> and the second substrate <NUM> may be see-through to allow a better view of the balls <NUM> and the housings <NUM>.

The balls <NUM> and the housings <NUM> may allow for movement of the inner liner <NUM> relative to the outer liner <NUM>. The balls <NUM> may allow for movement in all directions. The balls <NUM> may, be made of an elastomeric material and may compress if subjected to a force. While certain helmets may allow the balls <NUM> to roll freely, other helmets may couple the balls <NUM> to one, some or all of the inner liner <NUM>, the outer liner <NUM>, the first substrate <NUM>, and the second substrate <NUM>.

The housings <NUM> may each enclose a ball or a plurality of balls. The housings <NUM> may provide a limit of movement for the inner liner <NUM> relative to the outer liner <NUM>. The housings <NUM> may be made from an elastomeric material.

The first substrate <NUM> and/or the second substrate <NUM> may be substrates made from a relatively firm material, such as polycarbonate, to allow the balls <NUM> to translate. Alternatively, the material of the first substrate <NUM> and/or the second substrate <NUM> may be tuned to offer a resistance to the translation of the balls <NUM>. The first substrate <NUM> and/or the second substrate <NUM> may be made from an elastomeric material so that, in a resting position, the substrate may deform where the ball <NUM> contacts the substrate and thus offer a resisting force to movement of the ball <NUM>.

Additionally, certain helmets may not include the housings <NUM>. In such helmets, the balls <NUM> may be allowed to freely roll or substrates and/or the liners may include features to contain the balls <NUM> that serve the same function as the housings <NUM>, such as limiting the movement of the balls <NUM> or ramping up resistance force to movement of the balls <NUM> when the balls <NUM> move away from a "center" position.

<FIG> are isometric and cross-sectional views of a further impact absorbing system of a helmet useful for understanding the invention. The impact absorbing system <NUM> of <FIG> includes an outer liner <NUM>, an inner liner <NUM>, compression dampers <NUM>, and cylindrical dampers <NUM>. The compression dampers <NUM> and the cylindrical dampers <NUM> may replace the damper array. In <FIG>, the outer liner <NUM> may be see-through.

The compression damper <NUM> may be an off the shelf vibration compression damper. Alternatively, the compression damper <NUM> may be a custom shape. The cylindrical damper <NUM> may be coupled to the compression damper <NUM> or may be molded as the same part as the compression damper <NUM>. The cylindrical damper <NUM> may be bonded or coupled to the outer liner <NUM> or the inner liner <NUM>. There may be multiple cylindrical dampers coupled to the compression damper <NUM> and the cylindrical dampers may be coupled to both the inner liner and the outer liner.

<FIG> are isometric and cross-sectional views of yet another impact absorbing system of a helmet useful for understanding the invention. The impact absorbing system <NUM> of <FIG> includes an outer liner <NUM>, an inner liner <NUM>, and a damper array <NUM>. In <FIG>, the outer liner <NUM> may be see-through to allow a better view of the damper array <NUM>.

The damper array <NUM> may be a sheet of compressible material with internal void areas. The sheet may be designed to compress and shear when subjected to a force. The damper array <NUM> may shear and/or compress in any direction. The damper array <NUM> may be shaped into thin cross sections. The damper array <NUM> may compress or deform linearly or may be configured to smoothly ramp resistance to compression or deformation in any force curve that may be beneficial. While the damper array <NUM> includes void areas that are rectangular in shape, variations of the damper array <NUM> may include void areas that are of other shapes, such as circular, hexagonal, and other geometric shapes. The percentage of the damper array <NUM> that is made up of the void area may be varied depending on the desired compression characteristics.

While the damper array <NUM> of the helmet <NUM> does not include a substrate, other variations of the damper array <NUM> may include a first substrate and/or a second substrate. The substrates may serve to equalize the distribution of force.

<FIG> are isometric and cross-sectional views of an alternative to the impact absorbing system of <FIG>. The impact absorbing system <NUM> of <FIG> includes only a first substrate <NUM>. Unlike <FIG>, the dampers <NUM> may directly contact the outer liner <NUM> instead of counting a second substrate. Further variations may not include the first substrate <NUM>. Here, the dampers may be bonded, attached, or be molded into or from the same part as either the inner liner <NUM> and/or the outer liner <NUM>. Where the dampers are bonded or attached to a liner or multiple liners, the dampers may be the same material as the liners, or may be a different impact-absorbing material.

<FIG> is a partial cross-sectional view of a helmet with an impact absorbing system in accordance with an embodiment of the invention. <FIG> illustrates a helmet <NUM> with an outer liner <NUM>, an inner liner <NUM>, a substrate <NUM>, an attachment damper <NUM>, an isolation damper <NUM>, and a sliding disc <NUM>. The substrate <NUM> may, in certain embodiments, provide support for one or more of the attachment damper <NUM> and/or isolation damper <NUM>. The substrate <NUM> may be coupled to the inner liner <NUM>, the outer liner <NUM>, and/or another component of the helmet <NUM>.

The attachment damper <NUM> is coupled to the inner liner <NUM>, the outer liner <NUM>, and/or another component of the helmet <NUM> (e.g., the substrate <NUM>). The attachment damper <NUM> couples and positions the inner liner <NUM> relative to the position of the outer liner <NUM>. The attachment damper <NUM> may be coupled to the inner liner <NUM>, the outer liner <NUM>, the substrate <NUM>, and/or other component of the helmet <NUM> through adhesives (e.g., glues), through mechanical fasteners (e.g., pins, bolts, rivets, or other mechanical attachment components), and/or through friction or other attachment techniques (e.g., molded to or within such other components).

In certain impact situations, the inner liner <NUM> may move relative to the outer liner <NUM> or vice versa. The attachment damper <NUM> may then, after movement of the inner liner <NUM> relative to the outer liner <NUM>, return the inner liner <NUM> and/or the outer liner <NUM> to the original position or substantially the position before movement. In certain embodiments the attachment damper <NUM> may also be configured to receive forces imparted to the helmet and absorb the forces. Such forces may include oblique angle forces.

The isolation damper <NUM> is coupled to the sliding disc <NUM>. In certain embodiments, the isolation damper <NUM> may be bonded, mechanically fastened, friction fit, or coupled through other techniques to the sliding disc <NUM>. The sliding disc <NUM> is configured to move relative to (e.g., slide on) the inner liner <NUM> and/or the outer liner <NUM>. For example, if the helmet <NUM> is subjected to an oblique force, the inner liner <NUM> may move relative to the outer liner <NUM> and thus the isolation damper <NUM> and the sliding disc <NUM> may move relative to inner liner <NUM> and/or the outer liner <NUM>. Accordingly, in embodiments with some or all of the isolation dampers <NUM> coupled to sliding discs <NUM>, there may be lower resistance to lateral movement of the inner liner <NUM> relative to the outer liner <NUM> and, as such, lower amounts of oblique force may be transferred to the wearer. The helmet <NUM> also includes attachment dampers <NUM> that may then reposition the inner liner <NUM> relative to the outer liner <NUM> after an impact.

<FIG> illustrates certain components of the helmet of <FIG> in accordance with an embodiment. <FIG> illustrates the inner liner <NUM>, the substrate <NUM>, the attachment dampers <NUM>, and the sliding disc <NUM> of the helmet <NUM>. As shown, the substrate <NUM> may be a frame that various components of the helmet <NUM> (e.g., the isolation dampers <NUM> shown in <FIG>) may be coupled to. In certain embodiments, the isolation dampers <NUM> may be coupled to the substrate <NUM>. In certain embodiments, the substrate <NUM> may then be coupled to the inner liner <NUM> and/or the outer liner <NUM> via the attachment dampers <NUM>. In certain such embodiments, the inner liner <NUM>, the outer liner <NUM>, and/or the substrate <NUM> may include an opening that may receive a portion of the attachment damper <NUM>. The attachment damper <NUM> may then be inserted through the opening to couple together the inner liner <NUM>, the outer liner <NUM>, and/or the substrate <NUM>. In certain such embodiments, one or more of the openings may be sized to be a friction fit with the corresponding attachment damper <NUM>. As such, the inner liner <NUM>, the outer liner <NUM>, the substrate <NUM>, and/or the attachment damper <NUM> may then be coupled together without the need for adhesives. For example, in certain embodiments, the attachment damper <NUM>, the isolation damper <NUM>, and/or other components may be molded into one or more of the inner liner <NUM>, the other liner <NUM>, and/or the substrate <NUM>. In other embodiments, the single attachment damper <NUM> shown in <FIG> may be replaced with a plurality of components.

The sliding discs <NUM> may be configured to slide on one or more of the inner liner <NUM> and/or the outer liner <NUM>. The sliding discs <NUM> may include a sliding surface that may be of a greater surface area than that of the isolation dampers <NUM> attached to the sliding discs <NUM>. In certain embodiments, the sliding surface may be low friction, due to the material of the sliding disc <NUM> and/or due to a coating applied to the surface. Additionally, the sliding discs <NUM> may be coupled to the isolation dampers <NUM> through adhesives, mechanical fasteners, and/or through friction or other attachment techniques.

<FIG> is a partial cross-sectional view of an additional impact absorbing system of the helmet of <FIG> in accordance with an embodiment. <FIG> shows the sliding disc <NUM>, the isolation damper <NUM>, the substrate <NUM>, and the inner liner <NUM>. The isolation damper <NUM> may be configured to deflect when subjected to a force (e.g., a force from an impact). In certain embodiments, the isolation damper <NUM> may be configured to primarily receive forces applied in a direction normal to a surface of the inner liner <NUM>. Oblique forces may result in sliding of the isolation damper <NUM> and the sliding disc <NUM>.

In the embodiment shown in <FIG>, the isolation damper <NUM> is coupled to the inner liner <NUM>, and/or the outer liner <NUM> and may be coupled to another component of the helmet <NUM>. Additionally, the isolation damper <NUM> may be coupled to the substrate <NUM>. Additionally, as shown in <FIG>, the sliding disc <NUM> may include features to aid in the coupling of the sliding disc <NUM> to the isolation damper <NUM>. The embodiment shown in <FIG> includes, for example, locating features to aid in positioning the sliding disc <NUM> relative to the isolation damper <NUM> and vice versa.

<FIG> is a partial cross-sectional view illustrating additional embodiments of an impact absorbing system in accordance with an embodiment. While certain embodiments of the isolation damper <NUM> may include one shock absorbing features, the embodiment shown in <FIG> may include a plurality of shock absorbing features.

<FIG> illustrates portions of a helmet <NUM> with an outer liner <NUM>, an inner liner <NUM>, and an attachment damper <NUM>. The attachment damper <NUM> may be similar to other attachment dampers described herein. As such, the attachment damper <NUM> may aid in the positioning of the inner liner <NUM> relative to the outer liner <NUM> and/or another component of the helmet <NUM>. The outer liner <NUM> may include a lug <NUM> and a secondary damper <NUM>. The lug <NUM> may extend from a first surface of, for example, the outer liner <NUM> and may be configured to absorb force from an impact. Additionally, the lug <NUM> may also include a sliding surface. The sliding surface may allow the lug <NUM> to slide along a surface of the inner liner <NUM> and/or another component upon contact, thus allowing for greater movement of the inner liner <NUM> relative to the outer liner <NUM>. While the lug <NUM> is shown to be disposed on the outer liner <NUM> in the embodiment in <FIG>, other embodiments may dispose the lug <NUM> on the inner liner <NUM> and/or on both the inner liner <NUM> and the outer liner <NUM>. In certain embodiments, the outer liner <NUM> may include a recess on the side of the outer liner <NUM> opposite that of the lug <NUM>. Other embodiments may not include such a recess or may include isolation dampers (e.g., isolation damper <NUM>) that may include one or more such recesses.

Certain embodiments may include the secondary damper <NUM>. In certain embodiments, the secondary damper <NUM> may be disposed within the recess (e.g., within the recess opposite the lug <NUM> and/or within a recess of the isolation damper <NUM>), but other embodiments may dispose the secondary damper <NUM> elsewhere (e.g., on another portion of the outer liner <NUM> and/or the inner liner <NUM>). For example, certain other embodiments may include a through-hole within the outer liner <NUM> (e.g., at the location of the lug <NUM>) and the secondary damper <NUM> may be disposed within the through-hole or a portion of the through-hole.

In such embodiments, the lug <NUM> and/or the outer liner <NUM> may be made from a material with a first rate (e.g., elasticity or spring rate). The secondary damper <NUM> may be made from a material with a second rate. As such, the lugs <NUM> and the secondary damper <NUM> may each be tuned to provide protection at different forces and/or impact velocities. Accordingly, <FIG> shows an embodiment of a variable spring rate impact absorbing system. In certain embodiments, one or both of the lug <NUM> and the secondary damper <NUM> may be made from a non-Newtonian material. Such non-Newtonian materials may, for example, be different rates at different forces and/or impact velocities. As such, certain embodiments may not include the secondary damper <NUM> and may, instead, only have a non-Newtonian lug <NUM> that may be tuned to respond differently at different forces and/or impact velocities while other embodiments may include the lug <NUM> and the secondary damper <NUM>, as well as possibly other impact absorbing components. In embodiments with, at least, the lug <NUM> and the secondary damper <NUM>, one or more of the lug <NUM> and the secondary damper <NUM> may be made from non-Newtonian materials.

In certain embodiments, the lug <NUM> may be configured to engage before the secondary damper <NUM> and/or vice versa. As such, for the example of <FIG>, an impact may first result in deflection of the inner liner <NUM>. For a portion of the movement, the inner liner <NUM> does not contact the lug <NUM>. After a set amount of deflection, the inner liner <NUM> may contact and/or "engage" the lug <NUM>. As such, the lug <NUM> may then provide additional resistance towards movement of the inner liner <NUM>. When the lug <NUM> is initially engaged, the secondary damper <NUM> may not contact a component of the helmet <NUM> (e.g., an outer shell or another contact). As such, the secondary damper <NUM> may not be resisting movement of the inner liner <NUM>. After additional deflection, the secondary damper <NUM> may then engage and the resistance towards movement of the inner liner <NUM> may then increase due to the engagement of the secondary damper <NUM> (assuming the rates of the lug <NUM> and the secondary damper <NUM> are constant). The combined spring rate of the lug <NUM> and the secondary damper <NUM> may be higher than that of just the lug <NUM> itself.

<FIG> illustrate components of the helmet utilizing the impact absorbing system of <FIG> in accordance with an embodiment. Helmet <NUM> illustrated in <FIG> may be a further embodiment of the helmets <NUM> and <NUM> described herein. Helmet <NUM> may include an outer liner <NUM>, an inner liner <NUM>, a substrate <NUM>, attachment damper 1640A and snap base 1640B, lug <NUM>, and sliding disc <NUM>.

The substrate <NUM> of <FIG> may couple to the outer liner <NUM> and/or the inner liner <NUM> along an edge of the outer liner <NUM> and/or the inner liner <NUM>. The substrate <NUM> may include a plurality of the attachment dampers 1640A and snap base 1640B. In the embodiment shown in <FIG>, no isolation dampers may be coupled to the substrate <NUM>. However, the attachment dampers 1640A may be configured to couple to the outer liner <NUM>. The snap base 1640B may be coupled to the inner liner <NUM>. In certain embodiments, the snap base 1640B may be coupled to the inner liner <NUM> (e.g., molded within the inner liner <NUM> and/or coupled through other adhesive, mechanical, or other techniques). The snap base 1640B may be configured to receive a pin that may also be coupled to the substrate <NUM>. The attachment damper 1640A may be coupled to the substrate <NUM> and thus the attachment dampers <NUM>, the snap base 1640B, the substrate <NUM>, and any pins may position the outer liner <NUM> relative to the inner liner <NUM> (and vice versa).

In the embodiment shown in <FIG>, certain lugs <NUM> may include a sliding disc <NUM> coupled to the lugs <NUM>. Other lugs <NUM> may not include sliding discs <NUM>. Though some lugs <NUM> may include sliding discs <NUM> while others may not, both sliding disc <NUM> equipped lugs <NUM> and non-sliding disc equipped lugs <NUM> may be configured to slide on the inner liner <NUM>.

<FIG> illustrate various features of certain embodiments of an impact absorbing system in accordance with an embodiment. <FIG> illustrates two different embodiments of band <NUM>. The band <NUM> may be, for example, an elastic cord. In the first embodiment, the band <NUM> may be inserted into a receptacle of the inner liner at one end. The receptacle may hold the band <NUM> via a friction fit or features of the inner liner (e.g., openings that may encase the band <NUM>). The other end of the band <NUM> may be coupled to the outer liner via a mechanical cap. In the other embodiment, the first end of the band <NUM> may be received by a feature of the inner liner so that a portion of the band <NUM> is flush or below a surface of the inner liner. In embodiments where the band <NUM> is an elastic cord, elasticity of the band <NUM> may allow for movement of the inner liner 1904A relative to the outer liner 1902A from a first position while still returning the inner liner 1904A and the outer liner 1902A to the first position. As such, the band <NUM> may allow for greater deflection of the inner liner 1904A relative to the outer liner 1902A during an impact while still retaining the ability to return the liners 1902A and 1904B back to their original positions.

<FIG> illustrates additional embodiments of the isolation damper <NUM>. The isolation damper 1442A may include a cone <NUM>-<NUM>, a recess <NUM>-<NUM>, and a sliding disc <NUM>. The cone <NUM>-<NUM> may be configured to contact an inner liner and/or an outer liner. The geometry of the cone <NUM>-<NUM> may be determined according to the rate desired for the isolation damper 1442A. In certain embodiments, the cone <NUM>-<NUM> may allow for the isolation damper 1442A to be variable rate. In various embodiments, the recess <NUM>-<NUM> may or may not be filled with an additional material. Certain such materials may include impact absorbing properties that are different from that of the isolation damper <NUM>.

The isolation damper 1442B may include a first recess <NUM>-<NUM>, a second recess <NUM>-<NUM>, and a sliding disc <NUM>. One or both of the first recess <NUM>-<NUM> and the second recess <NUM>-<NUM> may be filled or partially filled with an additional material. The additional material may include properties similar to or different from that of the main portion of the isolation damper 1442B. Certain embodiments may include additional recesses that may also be filled with materials of different properties. Additionally, while <FIG> illustrates isolation dampers with cones and recesses, other embodiments may include, for example, lugs and/or liners with such cones and recesses.

<FIG> is a flowchart detailing an assembly process of a helmet. In block <NUM>, an outer liner is disposed within an outer shell. The outer liner is then coupled to the outer shell via, for example, bonding, adhesives, mechanical fasteners, mold-in, or other techniques. In certain embodiments, the outer liner may be molded within the outer shell and thus disposing and coupling the outer liner to the outer shell may occur substantially simultaneously.

In block <NUM>, an aligner is disposed within and coupled to the outer liner. The aligner may be coupled to the outer liner via, for example, bonding, adhesives, mechanical fasteners, mold-in, or other techniques described herein. In certain embodiments the aligner may be molded into the outer liner.

In block <NUM>, an inner liner is disposed within the outer liner. The inner liner is then coupled to the aligner in block <NUM> so that the outer liner, the aligner, and the inner liner may be coupled. Coupling may be via, for example, bonding, adhesives, mechanical fasteners, mold-in, or other techniques described herein. In certain such embodiments, the aligner may control the distance between portions of the outer liner and portions of the inner liner and may be configured to allow the distance to change upon receiving an impact. In certain embodiments, the inner liner, the outer liner, the aligner, and/or another components may include one or more isolation dampers and/or lugs. In embodiments where another component includes one or more isolation dampers and/or lugs, such a component may also be disposed within and/or coupled to the outer shell, the outer liner, and/or the inner liner.

Other embodiments of the impact absorbing system may include any of the impact absorbing system configurations detailed herein in various safety helmets (e.g., sports helmets, construction helmets, racing helmets, helmets worn by armed forces personnel, helmets for the protection of people such as toddlers, bicycle helmets, pilot helmets, and other helmets) as well as in various other safety equipment designed to protect a wearer. Non-limiting examples of such other safety equipment may include body armor such as vests, jackets, and full body suits, gloves, elbow pads, shin pads, hip pads, shoes, helmet protection equipment, and knee pads.

Claim 1:
A helmet (<NUM>, <NUM>) comprising:
an outer shell;
an outer liner (<NUM>; <NUM>) disposed within and coupled to the outer shell;
an inner liner (<NUM>; <NUM>) disposed within and coupled to the outer liner;
an aligner (<NUM>; <NUM>) coupled to the outer liner and the inner liner and configured to position the outer liner relative to the inner liner; and
a damper (<NUM>) disposed between the outer liner (<NUM>; <NUM>) and the inner liner (<NUM>; <NUM>) and configured to allow omnidirectional movement of the inner liner relative to the outer liner and the outer shell,
characterized in that:
the damper (<NUM>) comprises an isolation damper (<NUM>) coupled to one of the inner liner (<NUM>) or the outer liner (<NUM>), and
a sliding disc (<NUM>) is coupled to the isolation damper (<NUM>), wherein the sliding disc (<NUM>) is configured to move relative to the other one of the inner liner (<NUM>) or the outer liner (<NUM>).