SHOCK ABSORBING SYSTEM FOR PROTECTIVE EQUIPMENT AND DEVICES THEREFOR
A shock absorbing system for use with protective head gear includes a compressible member containing separate chambers that are inflated with a volume of a fluid (gas), and positioned between the skull and shell of the head gear. In one embodiment, the compressible member has at least one orifice that may vent fluid upon impact. The venting of fluid is directed outside of the shell through an expansion reservoir that may assume a bellows structure. This structure acts as a restrictive and temporary compartment for fluids. The expansion reservoir may assume a structure that permits temporary fluid transfer for the duration of impact. The structure will resist the introduction of fluid and actively return fluid to the “donating” chamber. The sealed and autonomous interior of the outermost chamber consists of smaller autonomous chambers that are inflated to higher pressures.
The present invention relates to protective equipment, and in particular to systems and devices for use in head safety.
BACKGROUNDProtective helmets are designed to prevent the human skull from fracturing. They are often not designed to protect the brain. When the head experiences linear or rotational acceleration, the brain moves within the skull and it is this behavior that is believed to cause concussions and other brain injury. It is the change in velocity of the brain within the skull that needs to be controlled. During impact, the skull's momentum stops, but the brain continues to move within the skull. If the time of impact is extended, the brain has the ability move closer to a synchronous motion with the skull thus minimizing the risk of injury.
Athletic helmets can be categorized into two segments: (ii) Single-impact; and (ii) Multiple-impact. Single impact helmets are disposable upon experiencing one impact. They are designed to fracture and cannot be used again. These types of helmets include helmets of the type used for cycling, motorcycling and skiing. They are able to absorb impacts by permanently deforming and thus eliminating the possibility of further use. Multiple-impact helmets, on the other hand, can sustain several impacts and allow the participants to continue to play after an impact event occurs. These types of helmets include helmets used in football, hockey and baseball.
Athletic helmets are typically comprised of a semi-rigid outer shell and interior layer of foam. These foams can be compressible (e.g. vinyl nitrile) as used in sport like hockey and football. Expandable polystyrene (EPS) is harder material and is often used in bicycling helmets.
Foam layers in the helmet have a thickness referred to as the “claim space”, which is defined as the available space between the skull of the wearer and the outer shell. Increasing the claim space by adding additional foam materials results in a larger helmet shell. Larger helmet shells are more susceptible to increased linear and rotational forces. For these reasons, the claim space needs to be designed with a minimum thickness.
For a given thickness of claim space within a helmet shell, there is a theoretical maximum amount of impact absorption. Foams typically can compress to approximately 70% of their original uncompressed thickness. Once full compression occurs in foam, it is deemed to have “bottomed out”. Bottoming out indicates that the foam is fully compressed and no further cushioning potential can be realized. When the foam is fully compressed under impact, the skull stops suddenly and the brain continues to move within the skull. Sudden head movements such as this place the brain at risk for injury.
The present invention moves closer to the maximum impact absorption potential by offering a multi-stage cushioning system that contains a vented outer chamber. The outer chamber contains one or more internal nested compression components. The outermost chamber would not realize a “bottoming out” effect since it contains one or more high-pressure chambers designed as compression devices.
Typically helmets of all types are designed for an upper-level of impact for the desired activity. They are designed to prevent skull fractures but they are not able to address the damage inflicted with the brain. Because of this, helmets often are not effective at providing comfort or safety at lower level impacts. The majority of head injuries occur in the mild-to-moderate range where we see concussions begin to occur. Current head protection testing procedures are designed for upper-level head injuries and do not adequately address linear and rotational forces on the brain.
SUMMARYIn the current environment of helmet safety, it is apparent that all helmet-wearing activities require better protection for the possible spectrum of impacts. In one embodiment, the present invention relates to a vented impact solution for providing comfort and safety at the lower levels of impact as well as providing protection with higher impact forces.
In another embodiment, the present invention relates to a thin-walled elastic or plastic shock absorbing and compressible device for use in head safety.
The present invention provides a solution to impact absorption by uniquely using the laws of thermodynamics and fluid flow.
In one embodiment, the invention is comprised of a single pressurized and vented chamber that contains one or more internal chambers that are sealed and pressurized. Interior chambers are fluid-filled and autonomous and are preferably made from flexible elastomer material and contain higher pressures than the outer chamber. The interior chambers will become engaged with the impact only in event of more severe impacts to the head. The impact absorption capability of the invention is an improvement over conventional foams by venting fluid of the outer chamber through an orifice to an expansion reservoir. This reservoir allows for extension of the outermost chamber through the helmet shell. The entire mechanism of the invention works together to extend the impact period.
By constricting the fluid flow through an orifice and using the impact's energy to extend the bellows structure, the force of the impact is better absorbed. Employing internal compression mechanisms can further extent the time of impact. The impact's time extension mitigates risk of injury by allowing the brain to move with a decreased change of velocity in relation to the skull.
The materials for the chambers are preferably made from a durable elastomer material. These are typically non-allergenic, flexible and offer prolonged use over multiple impacts in a wide variety of physical environments. The venting expansion bellows structure is in a contracted state while at rest. While the device is under impact, air flows through the orifice creating friction and thermal energy that offers energy absorption. The fluid from the outer chamber will flow through the orifice and reach the bellows structure extending it fully out through the helmet shell.
Once the fluid reaches the bellows structure it acts as an expansion reservoir to temporarily store the displaced fluid. If the impact has enough force, the head will engage the secondary and tertiary chambers. These chambers are closed and autonomous (non-transfer of fluid) and act as compression-only devices to prevent bottoming out of the invention.
Once the impact has been cushioned, the expandable bellows returns to its resting position and thus forces the fluid back into the outer chamber. The device is then ready for the next impact.
The bellows structure may be located directly on the outer chamber or may used with a stem so that it may be offset to accommodate the helmet design requirements. By providing an offset stem design, the ejecting bellows from the helmet are less likely to be blocked in the event of direct impact. Using offset stems means that site of impact on the helmet is NOT the site of ejection through the helmet shell.
Venting the outer chamber outside of the helmet functionally provides additional cushioning that would otherwise have to be achieved by increasing the claim space within the confines of the helmet shell.
During the production process, adjustments to the diameter of the venting orifice and pressure of the individual chambers can be made in order to accommodate the expected conditions of the helmet-wearing activity.
The invention structures are intended to be factory sealed units that will retain strength and internal pressures over multiple impacts. They may be replaced in the event of damage or deflation. Other inventions involve the displacement of air within air pockets and are confined within the protective outer shell and have not contained a reservoir vented outside of a helmet shell that actively resists the containment of fluid.
In an example embodiment, the device is a collection of fluid-venting and compressible components that, together, operate as a multi-stage cushioning system. Various components of the compressible member will be engaged as required by the forces of impact. At each stage of engagement, the device will offer additional cushioning capabilities in order to protect the head and extend the duration of impact. The compressible members are preferably produced from elastic and plastic materials (e.g. Thermoplastic Elastomer (TPE)) in order to react rapidly to impact. TPE material contains both elastic and viscous properties that allow it to stretch and rebound at a wide variety of temperatures. It is well suited for sports helmets as it falls well within the operating temperature range of participating indoor and outdoor activities. TPE contains properties to resist becoming permanently deformed under repeated mechanical stresses such as helmet impacts during participation in sport.
The compressible members would be used in a matrix layout and would ensure that each part of the inner surface of the protective headgear can supply sufficient protection to the wearer. The number of compressible members required in a helmet will be defined by the activity by which the helmet is used as well as the size of the outer helmet shell.
In one embodiment, the present invention combines: (i) One or more interior compression chambers; and (ii) An outer chamber used for the release of energy through to a bellows, also known as the expansion reservoir. This bellows structure consists of a series of convolutions (ridges) that permit extension along the longitudinal axis. The extension and compression movement is referred to as an axial movement. The convolutions are the smallest flexible unit contained within the bellows. When fluids are forced into the offset stem and subsequent bellows, they are directed to the convolutions. The convolutions allow for increased pressure strength and axial movement and as such, this design provides more stability than a non-bellows structure.
Volume of fluid can change in the bellows by compression or expansion due to impacts on the helmet. Regardless of the direction of impact to the compressible members, the result is the compression of the outermost chamber. This causes the extension of the bellows with an axial movement outward through the helmet shell. This controlled movement of fluids into the offset stem and bellows can extend the period of time of the impact. The extension of time for a given force of impact will mitigate injury to the wearer.
In the embodiments depicted in
The expandable bellows structure may be situated in various locations in relation to the outermost chamber of the invention. The offset stem mechanism would be used to locate the expansion reservoir and would not affect the functioning mechanism of the invention. The offsetting of the expansion reservoir would be dependent on the helmet shell design and levels of expected impacts sustained during activity.
It will be appreciated by those skilled in the art that other variations of the embodiments described below may also be practiced without departing from the scope of the invention. Further note, these embodiments, and other embodiments of the present invention, will become more fully apparent from a review of the description and claims which follow.
The embodiments herein will be understood from the following description with reference to the drawings, in which:
In the drawings, preferred embodiments of the invention are illustrated by way of example. It is to be expressly understood that the drawings are only for the purpose of illustration and as an aid to understanding, and are not intended as a definition of the limits of the invention. In this regard, the drawings are not to scale and relative dimension but serve to illustrate the principles of the invention in terms of fluid (gas) flow and energy absorption.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTSIn this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. In particular, all terms used herein are used in accordance with their ordinary meanings unless the context or definition clearly indicates otherwise. Also, unless indicated otherwise except within the claims the use of “or” includes “and” and vice-versa. Non-limiting terms are not to be construed as limiting unless expressly stated or the context clearly indicates otherwise (for example, “including”, “having”, “characterized by” and “comprising” typically indicate “including without limitation”). Singular forms included in the claims such as “a”, “an” and “the” include the plural reference unless expressly stated or the context clearly indicates otherwise. Further, the stated features and/or configurations or embodiments thereof the suggested intent may be applied as seen fit to certain operating conditions or environments by one experienced in the field of art.
The present disclosure relates to protective, shock-absorbing helmets that contain fluid-filled chambers. The chambers serve to dampen the force of impact and reduce the possibility of trauma to the brain and skull.
Now referring to the drawings,
The use of TPE allows for a wide operating temperature of the materials. The composition of the TPE can be properly selected for the expected range of use; this ensures it can remain in a soft rubbery state for the duration of participation.
The invention's components are comprised of an outer flexible chamber 80 that is pressurized to slightly above atmospheric levels. In this illustration, the ends of the invention 90 are sealed 86, however the manufacturing process may make it possible to have seamless embodiments. The relatively low pressure of the chamber ensures comfort when placed between the helmet shell and participant's head.
There is an orifice 81 located within the outer chamber 80. The orifice is vented through an offset stem 82 and into an expansion reservoir 83. It is capable of expanding and contracting the reservoir with an axial movement (up and down along axis). It permits expansion outside of the helmet shell through an opening in the shell. The size of the orifice can be appropriately selected to produce a rate-sensitive response to expected impacts. The size of the orifice will slow the impact and reduce forces by channeling fluid into the expansion reservoir 83. The process of moving fluid through an orifice will cause friction and produce thermal energy to help alleviate forces of impact.
The interior of the outermost chamber 80 may contain one or more chambers 84, 85. Interior chambers contain higher pressures than the chambers that surround them.
Innermost chambers would preferably contain the highest pressures as they are only engaged during the highest levels of impact.
The two inner chambers 84, 85 depicted in this view are sealed 86. They are autonomous compression devices and may not move fluids between other chambers.
Next, referring to
Each member's expansion reservoirs is forced through an open channel 40 through the helmet shell upon impact. While impact is underway, the participant's head 30 comes in contact with the bottom side of the member and compresses the outermost chamber. This moves fluid from the outermost chamber through an orifice into the offset stem and into the expansion reservoir. Once the fluid enters the reservoir, the additional pressure forces it to expand and open.
Now referring to
Forces 51 from the head push the outermost chamber 80 towards the helmet shell 34. As that outermost material moves closer to the shell, it engages the middle chamber 84 and pushes that towards the helmet shell. The middle chamber is a closed and compressed device and until the middle chamber is compressed from both the head and helmet shell side, it would not offer any significant cushioning protection.
3DD provides an axial view of the compressible member within the helmet shell.
Now referring to
Once impact forces are applied to the outermost chamber 80, fluids move through the orifice 81, into the offset stem 82 and vent the fluids using the expansion reservoir 83.
The members 91 may be placed in various orientations to allow impact locations from linear or shearing forces to cause venting in neighboring locations. In the event of an impact to the rear of the head, expansion reservoirs 83 would breach the helmet shell towards the rear and side of the head rather than directly back towards the forces of impact.
The impact forces may affect any number of the compressible members 91. Members that are not directly affected by the force of impact will remain at rest and the reservoir will remain in a closed position under the surface of the helmet shell 70.
The compressible member is shown in a state of rest in
When the compressible member is impacted, one or more of the expansion reservoirs 83 may inflate and protrude from a helmet shell. In more significant impacts, the interior chambers may be engaged and help provide further compression cushioning protection.
While one or more embodiments of this invention have been described above, it will be evident to those skilled in the art that changes and modifications can be made therein without departing from the essence of this invention. All such modifications are believed to be within the sphere and scope of the invention as defined by the claims appended hereto.
Claims
1. An shock absorbing helmet comprising:
- a plurality of compressible members arranged in accordance with the expected force and direction of impact, each compressible member itself comprising: a pressurized chamber comprising: an at least one orifice; an at least one expansion reservoir in fluid communication with the chamber, the expansion reservoir for facilitating the temporary exchange of fluids from the chamber to the reservoir in response to an impact; and an at least one connecting stem for permitting the movement of fluid between the pressurized chamber and the expansion reservoir; and a shell comprising a plurality of apertures, each aperture for receiving an expansion reservoir of each compressible member, each aperture for allowing each associated expansion reservoir to temporarily accept fluids and vent outside of the shell on impact;
- wherein the plurality of compressible members are positioned on the underside of the shell and secured from direct contact with a user's head.
Type: Application
Filed: Jun 5, 2017
Publication Date: Dec 6, 2018
Inventor: Martin Lachance (Cambridge)
Application Number: 15/614,215