FIELD OF INVENTION

The present invention relates to airbag systems and more particularly to a progressive airbag system in which at least one semi-rigid, resilient force distribution plate is positioned proximate a pair of thin, flat inflatable airbags. Once inflated, the airbags retain the gas/fluid provided thereto, while the plate or plates serve to redistribute a point of impact on the system across the entirety of the air bags (and, when employed, additional plates) so as to significantly reduce impact forces that otherwise would have been sustained by the object/person causing the initial point of impact. The airbags and plates are specifically engineered with features to distribute and dissipate force across their entire surface area, resulting in distributed deceleration of point load forces.

BACKGROUND

Currently, the two most familiar means of providing vehicle interior surface impact injury protection to the occupants of moving vehicles are the seat belt and airbag. While both devices are installed in every new commercial car and truck manufactured today, each plays a unique role in preventing impact and crash related injuries and when used together by vehicle occupants this combination saves thousands of lives each day. Modern vehicle seat belts protect occupants in several ways:seat belts increase the time it takes occupants to come to a complete stop within the vehicle during a collision;seat belts spread impact force over a greater area of the body, particularly the waist, chest, abdomen and shoulder;seat belts minimize occupant contact with the interior of the vehicle upon collision momentum transfer; andseat belts aid prevention of occupant ejection from the vehicle.

When combined with seat belt restraints, vehicle airbags provide enhanced occupant protection in cases where high speed collisions result in rapid bodily deceleration that would otherwise occur against rigid structures of the vehicle interior i.e. dashboard, windshield, door panels and roof. In these instances airbag deployment and inflation occurs only milliseconds after impact and prolongs the rate of bodily deceleration by carrying the occupant on its pressurized surface as it deflates under impact forces. Importantly, such airbags are configured so that the large surface area of the occupant's moving head, neck, and torso distributes those impact forces over a large area of the bag surface.

While the combination of vehicle seat belt restraints and inflatable airbags works well for characteristic front, rear, and side impact collisions, there are currently no commercial vehicles equipped with airbags that protect the head and neck from acute injury related to impact with the vehicle roof, door panels, headrest or other surfaces. These types of head and neck impacts, which include post impact whiplash, secondary collision impacts i.e. multiple vehicle collisions, and vehicle rollover events among others, is unique in that the head is a distinctive point load that will not distribute impact forces across large areas of an inflated airbag. Additionally, these vehicle interior surfaces of interest provide little space claim on which to mount characteristically large airbag restraints.

Further, conventional airbag systems are typically engineered to operate within a pressure gradient. That is, the system quickly inflates but includes valves or structures to allow the bag to deflate as impact is made. In this manner, the system absorbs energy and provides for constant deceleration. However, this approach means that the bag is only useful in absorbing an initial impact and, because the bag deflates thereafter, it offers little to no protection for repeated impacts (as may be expected in a rollover crash).

Accordingly, there is a need in the art for a compact airbag system that can be utilized to provide additional protection from a wide range of impacts including, but not limited to, head and neck impacts, secondary collision impacts (e.g., multiple vehicle collisions), vehicle rollover events, etc. These protections would be particularly useful in a low-profile airbag system installed in the rooftop of a vehicle along its passenger-facing sides.

SUMMARY OF INVENTION

The present invention relates to airbag systems and more particularly to progressive airbag system. In one embodiment, the present invention relates to an airbag system that comprises at least two airbag structures separated by a semi-rigid force distribution plate, where such a plate is located between a first and second airbags of the airbag system. Additional semi-rigid force distribution plates (e.g., where the arrangement of the at least two airbag structures and the at least two semi-rigid force distribution plates are arranged in an alternating cross-sectionally stacked pattern) and/or airbags are possible. Notably, the plates are semi-rigid, resilient, and elastically deformable so as to distribute point of contact loads across a broader surface area, while the airbags remain sealed after inflation and can be provided with structures to better accommodate deformation.

In another embodiment, the present invention relates to an airbag enclosure, the airbag enclosure designed to encompass an airbag system comprising: a first airbag structure, wherein the first airbag structure when deflated has a top surface and a bottom surface; a second airbag structure, wherein the second airbag structure when deflated has a top surface and a bottom surface; and a semi-rigid force distribution plate, wherein the first semi-rigid force distribution plate is located between the top of the first airbag structure and the bottom of the second airbag structure, wherein the airbag system is designed to be mounted on the bottom, or inside, surface of a vehicle roof. Such mounting may be accomplished by any conventional means, including hook-and-loop connectors, fasteners, cooperating fittings, adhesives, and other similar means.

In another embodiment, the present invention relates to an airbag system comprising: a first airbag structure, wherein the first airbag structure when deflated has a top surface and a bottom surface; a second airbag structure, wherein the second airbag structure when deflated has a top surface and a bottom surface; a semi-rigid force distribution plate, wherein the first semi-rigid force distribution plate is located between the top of the first airbag structure and the bottom of the second airbag structure; and an optional mounting plate, wherein the mounting plate is located on the top surface of the second airbag structure, wherein the airbag system is designed to be mounted on the bottom, or inside, surface of a vehicle roof or other rigid structure.

In other embodiments (complimentary to or distinct from those disclosed above), the airbag system includes manifolds to allow for quick inflation based upon information received from the vehicle communication bus and/or other sensors positioned at key contact points on the vehicle or its exterior. The manifold may connect to a rapidly deploying gas/fluid generator, possibly by means of energetic or chemical combustion modules or through the use of pressurized cartridges or cylinders. To the extent the generator is external to the airbag(s) and/or manifold, check valve or other appropriate structure are provided to ensure the airbags remain inflated. Still other aspects and embodiments are possible, as described herein.

