Abstract: The present invention relates generally to a helmet safety liner. More particularly, the invention encompasses a liquid-gel impact reaction liner for a motorcycle helmet. The present invention is also directed to a novel liquid-gel impact reaction liner for a half-shell motorcycle helmet. The inventive helmet could also have at least one cushion or intermediate layer which could be secured by one or more securing means.

Abstract: A concussion indicator that may easily be applied to a helmet is provided. The concussion indicator may visually or audibly provide indicators relating to impacts creating accelerations of the helmet that likely cause a concussion. In some embodiments, three separate indicators may be used within a single base; each indicator is configured to indicate at impacts relating to different concussion grades. A rear of the base is attachable to a surface such as an interior or exterior of a helmet. Upon a concussion triggering acceleration, the concussion indicator will indicate that a concussion is likely. This display may be seen or heard by observers if the indicator is on an exterior of the helmet, and by the user or someone who removes the user's helmet if it is on the inside of the helmet.

Abstract: Protective gear includes an outer shell layer connected to a middle shell layer through an outer energy and impact transformer layer. The middle shell layer is connected to an inner shell layer through an inner energy and impact transformer layer. The outer and inner energy and impact transformer layers flexibly connect the shell layers to absorb impact forces, rotational forces, shear forces, etc., and allow the various shell layers to move and slide relative to the other shell layers. The outer and inner energy and impact transformer layers may be constructed using gels, fluids, electro-rheological elements, magneto-rheological elements, etc. The protective gear may be formed as helmets or body protection for various activities and protect users from not only impact and penetrative forces, but rotational and shear forces as well.

Abstract: A helmet having blunt force trauma protection includes a prior art helmet and a replaceable impact layer. The replaceable impact layer preferably includes at least one air bubble layer, a removable attachment system and an outer layer of sheet material. The at least one air bubble layer includes a plurality of air bubbles created between two plastic sheets. Each bubble will burst upon a pre-determined impact. The plurality of bubbles preferably have a hexagon shape, but other shapes may also be used, such as round or square. The removable attachment system is preferably hook and loop fasteners, but other suitable removable attachment systems may also be used. At least one first pad of hook and loop fasteners is attached to an exterior surface of a prior art helmet and at least one second pad of hook and loop fasteners is attached to a bottom surface of the replaceable impact layer.

Abstract: Provided is a protective insert to be received into a pocket of a protective athletic headwear. The protective insert includes an outer layer, at least one pliable middle layer, and a pliable inner layer. The outer layer includes an arrangement of first openings that extend at least partially through the outer layer. The at least one pliable middle layer has at least one arrangement of openings that extend at least partially through the at least one pliable middle layer. The outer layer, the at least one pliable middle layer and the pliable inner layer are sealed such that the openings form sealed air pockets in the at least one first pliable middle layer between the outer layer and the pliable inner layer.

Abstract: Some embodiments described herein relate to an athletic helmet. The athletic helmet can include a shell, a suspension chassis, and several impact-absorbing pads. The suspension chassis can be disposed within the shell and configured to couple the pads to the shell. Each pad can include a membrane defining an interior volume. A valve can place the interior volume in fluid communication with the exterior of the membrane. In some embodiments, two or more structural members can be disposed within the interior volume. One structural member can be at least partially deformed when the athletic helmet is worn by a user.

Abstract: The present invention relates generally to a helmet safety liner. More particularly, the invention encompasses a liquid-gel impact reaction liner for a motorcycle helmet. The present invention is also directed to a novel liquid-gel impact reaction liner for a half-shell motorcycle helmet. The inventive helmet could also have at least one cushion or intermediate layer which could be secured by one or more securing means.

Abstract: An energy management system comprising a helmet shell, at least one pocket situated on an inside surface of the helmet shell and having an outer surface, and a bladder positioned inside of the at least one pocket. The outer surface of the at least one pocket is configured to allow the bladder to extend beyond the outside surface of the pocket upon impact.

Abstract: An energy management system having a helmet shell, at least one pocket situated on an inside surface of the helmet shell and having an outer surface, and a bladder positioned inside of the at least one pocket. The outer surface of the at least one pocket allows the bladder to extend beyond the outside surface of the pocket upon impact.

Abstract: An integrated helmet having blunt force trauma protection includes a helmet shell, an inner impact layer and the replaceable impact layer. The helmet shell is preferably fabricated from carbon fiber or a high impact plastic. A plurality of openings are formed through the helmet shell to reduce weight. The inner impact layer is attached to an inside surface of the helmet shell. The inner impact layer includes a plurality of deformable bubbles, which communicate with each other through a plurality of air channels. The inner impact layer will not burst upon impact. The plurality of deformable bubble chambers are filled with air to allow air to be displaced from one area to another area. The replaceable impact layer is attached to an outside surface of the helmet shell. The replaceable impact layer will burst upon impact.

Abstract: A helmet liner and a helmet assembly including a liner. A helmet liner includes a plurality of panels, each of the plurality of panels coupled to and foldable relative to at least one other panel of the plurality of panels at a seam, each of the panels including a gel layer.

Abstract: A helmet includes five layers; and outer shell, an intermediate foam component, a multi-cell bladder component filled with Ringer's Solution, a suspension rig, and a membrane component filed with a settable composition to conform to the wearer's head.

Abstract: Shock absorbers for integration into protective structures generally take the form of hollow, fluid-filled, compressible cells. In various embodiments, the cell enclosure includes one or more orifices, or vents, through which a fluid (such as air or water) can escape from the inner chamber formed by the enclosure.

Abstract: A pad assembly is provided for use with a protective sports helmet in a contact sport, the helmet having an opening. The pad assembly includes a pad member within a pad housing, and a retainer having a projection that fits within the helmet opening. The pad assembly also includes a cap detachably coupled to the retainer, the cap including a base portion that fits within the helmet opening and a flange portion that fits within a countersunk recess disposed around the helmet opening, the cap detachably receiving the projection of the retainer. A protective sports helmet having a pad assembly is also provided.

Abstract: A helmet is provided which is to be worn on the head of a helmet wearer and can be removed from the head with a comparatively small force. Operation for removing the helmet, including preliminary operation for it, can be performed easily and quickly. A recess-projection engaging mechanism to attach a blockish inside pad to a head protecting cap portion side includes an engaging pin on the inside pad side or head protecting cap portion side, and a notched engaging hole on the head protecting cap portion side or inside pad side. When pulling the inside pad outward from inside the head protecting cap portion at least partly, the engaging pin moves relative to outside the engaging hole through a notch of the engaging hole.

Abstract: Provided is protective athletic headwear that includes a body, band and protective inserts. The body has a first opening and a second smaller opening. The pocket band extends about the first opening to the interior of the body and partially toward the second opening. The band is free floating with respect to the body and configured to fit the head of the person. Further, the band includes pockets disposed about a base stitching that secure the band to the body. The protective inserts are configured to be received into pockets to provide a protective function to the head of the person. The protective inserts are disposed adjacently to one another about the band and extend from the base stitching of the band partially toward the second opening such that the body encloses the protective inserts in the band.

Abstract: Some embodiments described herein relate to an athletic helmet. The athletic helmet can include a shell, a suspension chassis, and several impact-absorbing pads. The suspension chassis can be disposed within the shell and configured to couple the pads to the shell. Each pad can include a membrane defining an interior volume. A valve can place the interior volume in fluid communication with the exterior of the membrane. In some embodiments, two or more structural members can be disposed within the interior volume. One structural member can be at least partially deformed when the athletic helmet is worn by a user.

Abstract: The present invention is a protective helmet having multiple zones of protection suitable for use in construction work, athletic endeavors, and similar activities. The helmet includes a hard outer protective that is suspended over a hard anchor zone by elastic cords extending between an elastomeric zone between the outer and inner zones. Fluid filed bladders are positioned in the elastomeric zone and bulge through one or more of a plurality of apertures located in the outer zone. In one embodiment, an additional crumple zone is present. The structure enables the helmet to divert linear and rotational forces away from the user's braincase.

Abstract: A method and apparatus for construction of a protective head covering, such as a helmet, to be worn by individuals engaged in activity that may, without the apparatus, cause concussive brain injury. The helmet, which is comparable in weight and envelope to conventional helmets, can be constructed from commercially available materials. The design features a dual shell concept where outer shell deflection under load triggers the primary attenuation mechanism. A second more rigid inner shell defines a space where one or more compartmentalized sealed elastomer energy absorbing cells are located. These cells contain a gas and/or liquid agent designed to adaptively convert potentially injurious normal impact force energy to energy that is channeled between the shells and therefore harmless to the wearer. A portion of this converted energy will be stored and then utilized to automatically re-set the apparatus for the next impact event.

Abstract: A head massager comprises a helmet having a front shell and a rear shell moveable relative to the front shell, a massage device and an adjustment device having a positive rotatable knob, a fixing pole fixed on the rear shell, a winding ring, two pulling ropes and a reverse locking device. The rear shell has a cavity and the front shell has two ends plug-connected with two ends of the rear shell. The knob and the winding ring are loosely sleeved on the fixing pole via holes. The knob has first bulged teeth around a hole, the winding ring has a loop of second bulged teeth around another hole. The first bulged teeth are indented joined to the second bulged teeth. One end of each pulling rope is connected to the end of the front shell, another end of the pulling rope is connected to the winding ring to rotate the knob in positive direction for moving the front shell by the two pulling ropes.

Abstract: A liner adapted to be interposed between the interior surface of a protective headgear and a wearer's head includes a plurality of networked fluid cells adapted to distribute and dissipate an impact force to the liner, and/or headgear with which the liner is used, across a larger area of the wearer's head as compared with the impact location, and also to dampen the tendency of the wearer's head from rebounding back from the impact location by transferring fluid through the network from fluid cells at the impact location to those in an opposed region. Discrete fluid cells interspersed among the networked fluid cells maintain the liner and/or the headgear in a predetermined orientation on the wearer's head. Fluid flow within the liner may be restricted or directed by configuring the fluid passageways. A liner may further include means for moving fluid into or out of the fluid cells.

Abstract: A helmet, especially a cricket or other sports helmet, comprises an outer shell member and, disposed adjacent its inner surface, a layer comprising an inflatable element operatively connected with inflation mechanism. The layer comprising the inflatable element preferably comprises a plurality of individual cells or pockets defined by a fluid-impermeable plastics membrane material, the individual cells or pockets being mutually in communication for pressurization and pressure-release purposes and connected to the inflation mechanism. The cells or pockets may contain impact-absorption or cushioning materials which are preferably porous to allow absorption and desorption of the inflation fluid.

Abstract: A protective helmet includes an outer shell and a controlled air dissipation (CAD) assembly installed within the outer shell. The CAD assembly includes an inner shell liner releasably mounted to the outer shell, a primary bellows unit disposed between an outer surface of the inner shell liner and the inside surface of the outer shell, and a secondary bellows unit disposed between an inner surface of the inner shell liner and the head of a person wearing the protective helmet. The primary bellows unit and the secondary bellows unit are thermally bonded to respective outer and inner surfaces of the inner shell liner.

Abstract: Provided is protective athletic headwear that includes a body, band and protective inserts. The body has a first opening and a second smaller opening. The pocket band extends about the first opening to the interior of the body and partially toward the second opening. The band is free floating with respect to the body and configured to fit the head of the person. Further, the band includes pockets disposed about a base stitching that secure the band to the body. The protective inserts are configured to be received into pockets to provide a protective function to the head of the person. The protective inserts are disposed adjacently to one another about the band and extend from the base stitching of the band partially toward the second opening such that the body encloses the protective inserts in the band.

Abstract: Protective gear such as a helmet includes multiple layers including an outer ball bearing layer and/or one or more energy and impact transformer layers. The ball bearing layer exposes multiple ball bearings on the outer surface of the protective gear to deflect and diminish shear forces and other rotational forces imparted onto the outer surface. In many examples, the ball bearings on the outer surface prevent the transfer of shear and rotational forces from the surface of a helmet onto a skull. The energy and impact transformer layers may also include various structures and materials used to dissipate mechanical energy applied to an outer layer or outer shell layer.

Abstract: Provided is a protective insert to be received into a pocket of a protective headwear. The protective insert includes a hard out plastic, at least one pliable middle layer and a pliable inner layer. The hard outer layer is configured to provide impact-resistance. The least one pliable middle layer has at least one arrangement of openings. Further, the pliable inner layer is configured to provide cushioning. The outer layer, the at least one middle layer and the inner layer are sealed with respect to one another such that the openings form closed air pockets. The air pockets are configured to absorb and distribute an impact to the outer layer about the at least one protective insert.

Abstract: A helmet structure without any hard outer shell has axially compressible cell units contained in a hemispheric frame by a thin fabric covering stretched over cup shaped cell retainers that have sidewalls of compressible foam. The frame is supported on the wearer's head on plastic foam posts that space the inner ends of compressible bladders from the wearer's head, and ambient air in the bladders compresses at impact, being vented then through openings for gradually absorbing such impact forces. Each bladder is vented into a space between the cup “bottom” and the outer end of a bladder. At least two cell sizes are provided, and some of these are on depending lobes in the frame, for protecting the wearer's ears and neck.

Abstract: A shock-absorbing helmet for sporting activities, e.g., including at least one damping layer covering a portion of the user's skull and an inner cap adapted to be inserted, at least partially, between the protective layer and the skull, the inner cap comprising at least one bladder. The inner volume of the bladder of the helmet defines an initial inner cap thickness, at least locally, in an initial customization configuration, and the helmet includes a mechanism for adjusting the inner volume of the bladder enabling, upon compression of the bladder, the discharge of a portion of the fluid contained in the bladder, the decrease in the inner volume of the bladder providing a localized reduction in the initial inner cap thickness in order to conform the inner cap to the morphology of the user's skull.

Abstract: Various helmets for protecting a wearer's head are provided that include a shell, at least one pad, and a lower portion coupled to the shell. The shell is configured to receive the wearer's head and can be formed from an elastomeric material. The pad is coupled to an interior of the shell and configured to be positioned between the wearer's head and the shell, where the pad can include one or more fluid filled bladders. The lower portion is configured to limit flexion, extension, and lateral bending of the wearer's head.

Abstract: Impact attenuating liner for headgear and headgear employing the liner, the liner positionable inside the headgear and comprising a cellular layer having an array of individual impact attenuating cells, each individual impact attenuating cells including an impact attenuating medium. The impact attenuating cells can comprise a gas, liquid, visco-elastic gel, foam, fiber or combinations thereof as well other impact attenuating medium. In another aspect, the impact attenuating liner has at least two layers, a cellular layer of and an impact attenuating layer under the cellular. The liner can include a cover. The liner can be removable from the headgear.

Abstract: An energy diffusing helmet assembly includes an outer hard shell and an inner fluid filled bladder. The hard shell defines a head cavity into which a head of a wearer is inserted. The fluid filled bladder is positioned within the outer hard shell. There is further provided a fluid filled impact dispersal field mounted on a torso of the wearer. A connective conduit connects the fluid filled bladder and the impact dispersal field. A force of impact exerted upon the fluid filled bladder increases pressure in the impact dispersal field through fluid via the connective conduit.

Abstract: This improved version of the Hard Hat Cushioning Device is more universal and can be used with virtually any hard hat, construction hat, bump cap, and similar hats designed for protection. The device allows the hat to fit more comfortably and securely and helps to prevent hair breakage while maintaining its decorative style. The cushioning effect reduces the restriction of blood flow to the scalp. The newly added air vents, and specific cotton outer material and inside batting material, improves air flow and circulation, making the hat more comfortable to wear while allowing warm air and perspiration to escape. These new improvements increase the ability of the cushioning device to act as a sweat band. Allowing air flow from inside the hat to the outside allowing for decreased temperature of the overall hat itself.

Abstract: A concussion indicator that may easily be applied to a helmet is provided. The concussion indicator may visually or audibly provide indicators relating to impacts creating accelerations of the helmet that likely cause a concussion. In some embodiments, three separate indicators may be used within a single base; each indicator is configured to indicate at impacts relating to different concussion grades. A rear of the base is attachable to a surface such as an interior or exterior of a helmet. Upon a concussion triggering acceleration, the concussion indicator will indicate that a concussion is likely. This display may be seen or heard by observers if the indicator is on an exterior of the helmet, and by the user or someone who removes the user's helmet if it is on the inside of the helmet.

Abstract: A helmet contains impact attenuating fluid (e.g., CO2, Air or Water) containing cells, sensors and electrically actuated exhaust valves for cushioning impact and decelerating a wearer's head after an impact. Accelerometers and a pressure sensor supply signals to a microcontroller, which opens an exhaust valve if accelerations (or pressure) exceed a threshold. Expelling fluid provides a cushioning and damping effect, decelerating the wearer's head. Acceleration data, fluid pressure data and GPS position data may be wirelessly communicated to a monitor computer system.

Abstract: The present invention provides protective headgear comprising a shell (26) having an inwardly facing surface which in use faces the head (10) of a user of the headgear and an outwardly facing surface which in use faces away from the head (10) of a user. An outer layer (28) overlies at least a portion of the outwardly facing surface of the shell (26) and rupturing means (30) is provided for fixedly attaching the outer layer (28) to the remainder of the headgear at one or more locations. The rupturing means (30) is configured so as to fail when a force greater than a selected threshold is received on an outer surface (28) of the headgear which acts in an at least part tangential direction to rotate the headgear and the head (10) of the user.

Abstract: A new and novel impact energy attenuation material, impact energy attenuation module employing the material and a fit system for optimizing the performance thereof is provided. Non-linear energy attenuating material consisting of a plurality of loose particles is employed for impact energy dissipation. The loose particles are preferably spherical elastomeric balls. An impact energy attenuation module includes a container that holds the loose particles. The impact energy attenuation module can be provided in a wide range of sizes and shapes and the loose particles can be provided in different materials, sizes, density, compaction and hardness to suit with the application at hand. A matrix of impact energy attenuation module are provided about the surface of a shell to provide the required impact energy attenuation. The material, impact energy attenuation module and system of the present invention are well suited for protection of body parts and other cushioning and protection needs.

Abstract: The present application provides a helmet. The helmet includes an energy absorbing layer (2) and a sliding facilitator (5). The sliding facilitator is provided on an inside surface of the energy absorbing layer (2). A method of manufacturing the helmet is further provided. The method includes the steps of: providing an energy absorbing layer in the mold, and providing a sliding facilitator contacting an inside surface of the energy absorbing layer.

Abstract: A protective molded gel headgear for protecting a wearer during an impact to the wearer's head is provided. The molded gel headgear has a shape that approximates the outer periphery of portions of the wearer's head to be protected. The molded gel headgear is made of an energy absorbing gel material to reduce the impact to the wearer's head during a head-impact event. One or more methods for producing the headgear are also provided.

Abstract: An impact attenuating bladder for lining a helmet shell, the bladder having: a top layer and a bottom layer of fluid impermeable material defining a fluid containment chamber; a fluid outlet in flow communication with the fluid containment chamber; and a fluid release control valve in flow communication with the outlet, the control valve having: a sacrificial elastic membrane with an inside surface in flow communication with the fluid containment chamber and an outside surface, where the outside surface is disposed in an initial configuration when the bladder contains fluid at a minimum initial pressure, and in a rupture configuration when the bladder contains fluid at a maximum rupture pressure; and a membrane rupture device with a membrane engaging tip disposed a predetermined initial distance from the membrane in the initial configuration, and engaging the membrane in the rupture configuration.

Abstract: An airbag (20) for protecting the head of a user in case of an accident is hereby presented. The airbag comprises an inflatable inner bag (21, 40, 50, 60) surrounded by an outer bag (22), wherein the structure of the outer bag (22) defines the shape of the airbag (20) when the inner bag (21) is inflated, and wherein said inner bag (21, 40, 50, 60) comprises a plurality of elongate first chambers (28, 29, 210, 211, 41, 42, 43, 44, 45, 46, 47, 48, 65, 66, 69, 610, 611, 612, 613, 614), each of which elongate first chambers forms a head protective part when inflated.

Abstract: A protective helmet and insert for reducing the possibility or severity of a concussion are provided. The insert comprises a shock absorbing portion and a flexible liner portion, the shock absorbing portion to be disposed between a helmet shell and the liner portion. The shock absorbing portion can possess a substantially constant resistive deformation force characteristic for reducing the peak G-force applied to the head during an impact. The insert can comprise a plurality of flexible liner connectors for movably interconnecting the liner portion to a helmet shell to allow for the flexible movement of the liner portion relative the shell. The liner connectors can be in the form of vent shaft walls that each defines a vent shaft for providing fluid communication between a headspace of the liner and an outer side of the shock absorbing portion to ventilate the headspace. A helmet comprising the liner is also provided.

Abstract: A helmet has a ventilated shell, ventilated padding and a ventilated liner of plural cells mounted to the padding for engaging a wearer's head. The liner has top and bottom flexible sheets fused around their perimeter, the bottom sheet having plural round or oval toroidal cells and plural round or oval closed cells, the openings in the toroidal cells extending through the top sheet. Foam at least partly fills each cell. Cells under a crown of the shell are connected in a first circuit with a valve for inflating these cells and a other cells under temporal and occipital portions of the shell are connected in a second inflation circuit with a valve for inflating the second plurality of the cells. Cells under the frontal portion not being inflatable and being substantially filled with foam padding.

Abstract: Safety head wear for use for example in high risk activities such as sports and industrial purposes where protection from head injuries is required. Components are provided inserted between the liner and outer shell and consists of two parts; a chamber or bladder and a fluid or gel like material. The fluid or gel material is contained in the chamber or bladder and is positioned in such a way to create low friction between the surface of the shell and liner or liner and head. It can also be used on the outer surface of the shell or placed within two layers of the liner. The device provides a method of independently managing both compression and shear force characteristics of the helmet around the head designed to decrease brain trauma resulting from high linear and angular acceleration during impacts to the helmet.

Abstract: The present invention is a protective helmet having multiple zones of protection suitable for use in construction work, athletic endeavors, and similar activities. The helmet includes a hard outer protective that is suspended over a hard anchor zone by elastic cords extending between an elastomeric zone between the outer and inner zones. Fluid filed bladders are positioned in the elastomeric zone and bulge through one or more of a plurality of apertures located in the outer zone. In one embodiment, an additional crumple zone is present. The structure enables the helmet to divert linear and rotational forces away from the user's braincase.

Abstract: A protective impact-absorbing headgear liner for use with various types of helmets and protective gear or clothing. The lining material has unique impact absorbing properties to additionally protect a wearer from impact related injuries. The headgear liner has a band and crown which are variously shaped and positioned to received impact-absorbing pads. The position of the pockets depends on the helmet style. In one example the liner is a stretchable material. Impact absorbing pads as described herein may be used in a variety of clothing and protective gear to protect from impact injury. Examples are football shoulder ads, thigh pads, bicycle helmets and the like. The liner may also be an expanded foam. A preferred pad material is a gel containing a thermoplastic elastomer.

Abstract: Provided is protective athletic headwear that includes a body, band and protective inserts. The body has a first opening and a second smaller opening. The pocket band extends about the first opening to the interior of the body and partially toward the second opening. The band is free floating with respect to the body and configured to fit the head of the person. Further, the band includes pockets disposed about a base stitching that secure the band to the body. The protective inserts are configured to be received into pockets to provide a protective function to the head of the person. The protective inserts are disposed adjacently to one another about the band and extend from the base stitching of the band partially toward the second opening such that the body encloses the protective inserts in the band.

Abstract: The present invention features a helmet 100 for cooling a head of a person. In some embodiments, the helmet comprises a top portion 110 covering the scalp region of the person's head, a neck portion 120 covering the neck region of the person's head, a tube 130 embedded in the helmet 100, wherein a circular portion 132 of the tube is disposed in the top portion to lay over the person's scalp region and a tail portion 134 of the tube runs down the neck region 120. Further, a first end of the tail portion 136 of the tube fluidly connects to the circular portion of the tube, and a second end of the tail portion 138 of the tube comprises a cap 140 that can open for drainage of a content in the tube. In some embodiments, a pressurized refrigerant container 150 fluidly connects to the tail portion 134 of the tube, wherein a pressurized refrigerant can be released into the tube when a first valve is opened.

Abstract: A protective member such as a helmet includes an outer layer and an inner layer interconnected by multiple connectors, such as extension springs, under tension along their longitudinal axis. The connectors absorb energy from an impact force by resisting further tension along their longitudinal axis and allow the outer layer and inner layer to move relative to each other. In the helmet application, the head of a user experiences less impact force, reduced change in momentum or position of the head and neck, reduced head and neck loads and reduced amounts of linear and rotational acceleration. The protective member can be used in numerous applications and environments, including for participants in sports, in applications including bumpers, passenger cabins, car seats and beds.

Abstract: A protective helmet includes an outer shell and a controlled air dissipation (CAD) assembly installed within the outer shell. The CAD assembly includes an inner shell liner releaseably mounted to the outer shell, a primary bellows unit disposed between an outer surface of the inner shell liner and the inside surface of the outer shell, and a secondary bellows unit disposed between an inner surface of the inner shell liner and the head of a person wearing the protective helmet.

Abstract: Devices with one or more internal flexibility sipes, such as slits, to provide improved flexibility, improved cushioning to absorb shock and/or shear forces, and improved stability. An internal sipe is formed by at least a portion of two opposing internal surfaces that can move relative to each other in a sliding sideways motion. Siped devices can be used in most existing products, including helmets and/or helmet liners.