Airbag device

The disclosed airbag device may protect a vehicle occupant in a vehicle seat of a motor vehicle. The airbag device may comprise an airbag cushion that functions as a side airbag and as a curtain airbag so as to cover an area of a portion of an interior side wall of the vehicle, a portion of a window glass, or a combination thereof upon deployment. The airbag cushion may have a width in fore and aft directions and a height which result in the portion of window glass, the portion of the interior side wall, or the combination thereof being covered in a vicinity of the vehicle occupant such that a thorax, a pelvis, a shoulder and a head of the vehicle occupant are protected from directly contacting adjacent interior side surfaces of the motor vehicle during a crash event.

BACKGROUND

Buses and motor coaches today use the “compartmentalization” approach to occupant safety which provides effective protection to passengers when the bus or motor coach is involved in a frontal- or rear-impact collision. “Compartmentalization” was not designed or intended to protect occupants during lateral impact events.

There are no known effective applications of seat-mounted side-curtain airbags in buses or motor coaches.

SUMMARY OF THE INVENTION

According to one embodiment of the present invention, an airbag device for protecting a vehicle occupant in a vehicle seat of a motor vehicle may comprise an airbag cushion that functions as a side airbag and as a curtain airbag so as to cover an area of a portion of an interior side wall of the vehicle, a portion of a window glass, or a combination thereof upon deployment. The airbag cushion may have a width in fore and aft directions and a height which result in the portion of window glass, the portion of the interior side wall, or the combination thereof being covered in a vicinity of the vehicle occupant such that a thorax, a pelvis, a shoulder and a head of the vehicle occupant are protected from directly contacting adjacent interior side surfaces of the motor vehicle during a crash event.

According to another embodiment of the present invention, a vehicle may comprise a vehicle seat comprising a back support and a sitting pad; and an airbag device for protecting a vehicle occupant in the vehicle seat. The airbag device may comprise an airbag cushion that functions as a side airbag and as a curtain airbag so as to cover an area of a portion of window glass, a portion of an interior side wall of the vehicle, or a combination thereof upon deployment. The airbag cushion may have a width in fore and aft directions and a height which result in the portion of window glass, the portion of the interior side wall, or the combination thereof being covered in a vicinity of the vehicle occupant such that a thorax, a pelvis, a shoulder and a head of the vehicle occupant are protected from directly contacting adjacent interior side surfaces of the vehicle during a crash event.

DETAILED DESCRIPTION

The designed airbag device according to various embodiments of the present invention is designed especially for use in buses and motor coaches, especially, for example, in school buses designed to comply with the Federal Motor Vehicle Safety Standard (FMVSS) 222. The disclosed airbag module provides protection over a larger coverage area than any known seat-mounted side airbag as the airbag cushion is wider and taller than that known in the art. The airbag cushion may cover window glass and side walls of a bus or motor coach to fulfill the requirements of a side airbag and a curtain airbag in one package; thus providing curtain protection with side impact protection. As a result, during a “rollover” crash event, unrestrained vehicle occupants will not be ejected from the vehicle (i.e., bus or motor coach), thus preventing potentially serious injury or death.

The disclosed seat-mounted, side-curtain airbag device is designed for use in buses (such as school buses), motor coaches, or similar vehicles. It is noted, however, that the airbag device may be used in other appropriate vehicles.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.FIG. 1discloses the general environment in which the airbag device may be used. As can be seen, a row of vehicle seats12are disposed in an interior compartment of a motor vehicle10, such as a bus or motor coach. The vehicle seats12may comprise a back support14, a sitting pad16, and a support structure18that may be fixed or slidably attached to the floor20and/or wall of the interior compartment of the motor vehicle10. An airbag device22for protecting a vehicle occupant in the vehicle seat12fits inside an interior compartment24located in the back support14of the seat12.

The airbag device22may comprise an airbag cushion102as seen inFIGS. 2,3(A), and3(B). The airbag cushion is formed from two or more panels that are attached together using stitching, adhesive, or other forms of attachment known in the art. For example,FIGS. 3(A) and 3(B)show an airbag cushion102formed by a plurality of seam lines108created by stitching the panels104and106together. The seam lines108may be used to attach the panels104and106along the outer periphery thereof, thus creating outer seams110to form an enclosure which captures gas from an inflator so that the airbag cushion may be inflated. Optionally, seams lines108may be made within the outer periphery, thus creating inner seams112to form a plurality of inflation chambers114. The airbag cushion is in fluid communication with an inflator116via a fill tube118, as seen inFIG. 2. The details of the inflator and fill tube will be described later. Any suitable material may be used for the panels104and106, such as Nylon or other suitable polymer. The airbag cushion (i.e., the two panels104and106) may be preferably sealed so as to maintain an extended “inflation time” of 3-8 seconds at >50% peak pressure to provide protection during long-duration impacts and rollover conditions experienced by buses or motor coaches. Also, note that the panels104and106may be, in one embodiment, formed from a single sheet of fabric (or other suitable material) folded back on itself and sewn around at least three sides of the perimeter to create an enclosed volume.

The size of the airbag cushion102is dimensioned such that the cushion may function as a side airbag and as a curtain airbag so as to cover an area of an interior wall of the motor vehicle upon deployment. The area covered by the airbag will be described in terms of width W and height H. The width W is the maximum distance of the deployed airbag running in the front to rear (or horizontal) direction X of the vehicle. The height H is the maximum distance of the deployed airbag running in the top to bottom (or vertical) direction Y of the vehicle.

FIG. 13shows an embodiment of the deployed airbag cushion which shows the relation between the deployed airbag cushion102and a vehicle occupant50, such as a child or an adult. The airbag cushion102ofFIG. 13functions as a side airbag and as a curtain airbag so as to cover an area of a portion of an interior side wall52, a portion of a window glass54, or a combination thereof of the vehicle upon deployment. The airbag cushion102may have a width in fore and aft directions and a height which result in the portion of window glass54, the portion of the interior side wall52, or the combination thereof being covered in a vicinity of the vehicle occupant50such that a thorax56, a pelvis58, a shoulder60and a head62of the vehicle occupant50are protected from directly contacting adjacent interior side surfaces of the motor vehicle during a crash event. The airbag cushion ofFIG. 13may have the same, similar, or different dimensions from the embodiments of the airbag cushion described in reference toFIG. 4and the following discussion.

For the embodiment of the airbag cushion inFIG. 4, the area covered by the deployed airbag cushion102may have a width W greater than a distance DW spanning from a substantially vertical rear surface28of a back support14of the vehicle seat12to a front edge26of the sitting pad16of the vehicle seat. Additionally, the area covered by the deployed airbag cushion102may have a height H greater than a distance DH spanning from a top surface30of the sitting pad16to the top edge32of the back support14. This configuration may be advantageous because of government legislation requiring taller seat backs in school buses.

The size of the airbag cushion may be any suitable size such that its function as a side airbag and a curtain airbag may be performed. For example, the width W of the airbag cushion102may be a distance greater than a distance spanning from the substantially vertical rear surface28of the back support14to a point in front of a second substantially vertical rear surface34of a second back support36of a second vehicle seat38located in front the vehicle seat12, as seen inFIG. 4. Other embodiments of the present invention may include different starting and/or ending points in the determination of the distance DW (the distance from which the width W of the airbag is judged to be greater than).

Examples of suitable starting points for DW may include the substantially vertical rear surface28of the back support14, the substantially vertical front surface29of the back support (seeFIG. 1), a vertical plane intersecting either the front surface29or the rear surface28of the back support14, a vertical plane located behind the rear surface28of the back support. Examples of suitable ending points for DW may include the front edge26of the sitting pad16of the vehicle seat, a point in front of a second substantially vertical rear surface34of a second back support36of a second vehicle seat38located in front of the vehicle seat12, a point in front of a second substantially vertical front surface35of the second back support36of the second vehicle seat38located in front of the vehicle seat12, a vertical plane that intersects the second substantially vertical rear surface34or the second substantially vertical front surface35of the second back support36of the second vehicle seat38located in front of the vehicle seat12. In this context, substantially vertical is a direction in which an object is at an angle of less than 30° or less from the vertical direction Y, such less than 25°, 20°, 15°, 10°, 5°, or 0° from the vertical direction Y.

Alternatively or additionally, the height H of the airbag cushion102may span a distance DHH spanning from the top surface30of the sitting pad16to a point substantially near a roof40of the vehicle10. Other embodiments of the present invention may include different starting and/or ending points in the determination of the distance DH (the distance from which the height H is judged to be greater than). Examples of suitable starting points for DH may include the top surface30of the sitting pad16, the bottom surface31of the sitting pad16, or a horizontal plane intersecting either the top or bottom surfaces of the sitting pad. Examples of suitable ending points for DH may include the top edge32of the back support14, a point substantially near a roof40of the vehicle10, the roof40of the vehicle10, or a point substantially midway between the top edge32of the back support14and the roof40of the vehicle.

As previously mentioned in relation toFIG. 2, the airbag device may have an inflator116and a fill tube118fluidly connecting the inflator116and the airbag cushion102, wherein the fill tube118is typically disposed along a length of the back support14of the vehicle seat12. The fill tube118and inflator116may take many different forms. For example, inFIGS. 1-2, the inflator may be attached at one end of the fill tube118while the other end of the fill tube118is inserted into an inflow passage120of the airbag cushion102. In this embodiment, the fill tube118may have a bend122such that the open end124of the fill tube118reaches into at least one of the inflation chambers114. The bend122may be curved and may form a 90° angle; however, other possible angles may be used, such as 10°, 30°, 45°, 60°, 120°, 135°, 150°, or any angle therebetween. Also, the open end124may have a welded or crimped cap with pierced, drilled, or similarly formed holes in the fill tube118to allow gas to exit the tube118in a direction substantially perpendicular to the axis of the tube.

According to another embodiment, as shown inFIG. 5, a fill tube201may have a plurality of apertures202along a circumferential surface of the fill tube201. The plurality of circumferential apertures202may comprise an aperture204on one end of the fill tube201having a larger diameter than an aperture206located at the other end of the fill tube201. Alternatively or additionally, the aperture204may have a larger diameter than all the other circumferential apertures202. The larger hole204may be placed at the upper portion of the deployed airbag cushion102(seeFIGS. 11(A) and 11(B)) where there may be a plurality of inflation chambers114′ that are not in direct fluid contact with an aperture of the fill tube118.

Also, the inflator116′ may be integral with the fill tube201at a midpoint of the fill tube. In this embodiment, the airbag cushion102can be rolled up so as to fit into the interior compartment of the back support14of the seat12. The fill tube201and inflator116are inserted into the airbag cushion102at a receiving portion212so that the fill tube201runs along a length of the airbag cushion102. In this embodiment, the receiving portion212may be formed between the seams110at the outer periphery of the airbag cushion102and a series of internal seams208running substantially parallel to the outer periphery. The spaces210between the internal seams208are used as flow passages so that the gas flowing through the apertures202enter through the inflatable chambers114via these spaces210. Optionally, the airbag cushion may then be inserted into a sleeve302with tearable seams304before the assembly is inserted into the back support14of the seat12. According to one embodiment of the present invention, a short fill tube (<350 mm) may be included to ensure the cushion integrity and address inflation efficiency challenges associated with remotely-mounting an inflator. The inclusion of the inflator within the seat itself may decrease the cost of manufacture while maintaining functionality.

According to another embodiment, shown inFIG. 6, the fill tube401has a plurality of apertures402along a circumferential surface of the fill tube401. The plurality of circumferential apertures402may comprise an aperture404on one end of the fill tube401having a larger diameter than an aperture406located at the other end of the fill tube401. Alternatively or additionally, the aperture404may have a larger diameter than all the other circumferential apertures402. The larger hole404may be placed at the upper portion of the deployed airbag cushion102(seeFIGS. 11(A) and 11(B)) where there may be a plurality of inflation chambers114′ that are not in direct fluid contact with an aperture of the fill tube118.

Also, the inflator116″ is attached at a middle point of the fill tube401by using clamps, attachment bands, straps, or other attachment devices known in the art so that gas generated by or released from the inflator116″ is channeled into the inflow aperture408of the fill tube401. A seal may be desirable at the interface of the inflator116″ and the fill tube401so that there are no leaks as the gas passes from the inflator116″ into the inflow aperture408of the fill tube401. In the embodiment ofFIG. 6, the airbag cushion102can be folded up so as to fit into the interior compartment of the back support14of the seat12. The fill tube401and inflator116″ are inserted into the airbag cushion102at the receiving portion212so that the fill tube401runs along a length of the airbag cushion102. The receiving portion212may be formed between the seams110at the outer periphery of the airbag cushion102and a series of internal seams208running substantially parallel to the outer periphery. The spaces210between the internal seams208are used as flow passages so that the gas flowing through the apertures402enter through the inflatable chambers114via these spaces210.

Optionally, the airbag cushion may then be inserted into a sleeve302with tearable seams304(as seen inFIG. 5); or adhesive strips410(as seen inFIG. 6) or bands with tearable seams may be disposed at various points along the assembly so that the airbag cushion may maintain its folded condition before the assembly is inserted into the back support14of the seat12. The combination of the inflator and fill tube would preferably ensure all chambers of the airbag cushion will be inflated and in position to provide occupant restraint within approximately 22 ms.

The airbag cushion102may be folded or rolled up, as previously mentioned. For example, the use of a rapidly-deploying directional fold, along with a rapid-onset inflator, may be used so as to offset the very fast intrusion rate typically experienced in side impact events.

Once the airbag cushion102, the fill tube, and the inflator116are assembled, this airbag assembly is placed into an interior compartment or void volume24of the back support14. For example, the back support14of the seat12may be a polymeric foam with a cut-out space in which the airbag assembly is placed. An aperture exists in the seat covering that covers the polymeric foam so that the airbag assembly may be inserted in the back support14. The aperture may be along the side of the back support14.

The inflator mounting position or location may be positioned within the vehicle seat so as to optimize for functionality and comfort of the occupant. For example, the airbag device may permit comfortable occupant seating by locating the airbag assembly in the seat12in such a way that the occupant does not come into contact with any “hard points” of the airbag device. As shown inFIG. 7, by packaging the rigid- or semi-rigid components (e.g., metal, injection molded or extruded plastic) of the airbag device in the seat between 0 mm and 500 mm above the seat bight line and/or at least 10 mm behind the A-surface of the seat, the hard points on the airbag device remained below and/or behind the shoulder of the occupant, thus preventing the occupant from feeling the airbag when sitting in the seat.

After the airbag assembly is placed in the back support of the vehicle seat, the aperture in the seat covering is closed or covered. According to one embodiment, seen inFIG. 8, the back support14of the vehicle seat12has a tearable seam501on the seat covering that covers the polymeric foam. The tearable seam501ruptures during the deployment of the airbag cushion. According to another embodiment, as seen inFIG. 9, the back support has a tamper resistant panel502, such as a tamper resistant A-surface cover. The panel502, for example, may be hinged, attached by adhesive, mounted by fasteners, and/or fixed by stitching. After the airbag assembly is installed in the seat, the airbag cushion deploys through the tearable seam or the tamper resistant panel. With the tearable seam or tamper resistant panel, the airbag may still be deployed through these devices while ensuring that the airbag device is not tampered with by vehicle occupants.

The location of the tearable seam501or the tamper resistant panel502along the side of the back support14of the vehicle seat may provide the benefit of preventing any tampering with the airbag assembly because of the limited space between the interior wall of the bus or motor coach and the seat side. In other words, by packaging the airbag device inside the back support of the seat itself, and with the limited distance between the outside edge of the seat and the interior wall of the bus or motor coach, the airbag is protected from unauthorized access. Thus, the airbag is protected from tampering and/or vandalism, which may be a challenge especially in school buses. With such a configuration, the seat12must be removed from the vehicle before the airbag device can be accessed.

After each seat12in the bus, motor coach, or similar vehicle is installed with an airbag device, the individual inflators will be activated by an occupant safety system. As seen inFIG. 10, the bus or motor coach comprises an airbag control module602, one or more sensors604used to detect impacts which are known in the art, and one or more airbag devices22in the seat(s). The control module602receives signals from the one or more sensors. If the control module determines that a crash event is occurring, it sends a deployment signal to one or more airbag devices22if the crash parameters deem a deployment in one or more airbag devices22is necessary to protect one or more occupants.

Once a signal is sent to the airbag device22, the inflator116is activated causing gas to flow through the fill tube118. As can be seen inFIGS. 11(A) and 11(B), the airbag cushion102inflates by the flow of gas flowing through the plurality of apertures of the fill tubes in which each aperture of the fill tube118may inflate a particular chamber114of the airbag cushion102. The larger hole204may be placed at the upper portion of the deployed airbag cushion102where there may be a plurality of chambers that are not in direct fluid contact with an aperture of the fill tube118. The inflating airbag cushion102eventually breaks through the tearable seams501, or pushes away the tamper resistant panel502so as to exit the back support14of the seat12. As the airbag inflates and covers the interior wall and windows of the bus or motor coach, the airbag cushion102may be able to fold if it contacts the seat in front of the seat in which it is housed so that the airbag cushion is fully deployed along the wall and windows. In addition, the airbag cushion deploys between the seat occupant and the window/wall of the vehicle to push the seat occupant inward and away from the side impact so as to prevent the occupant from being struck from above or being caught between the airbag cushion and the window/wall.

Other embodiments of the disclosed airbag device are also contemplated. For example, instead of a filling tube with a plurality of apertures along its circumferential surface, a filling tube with an axial hole (as seen inFIGS. 1-2) or a filling tube with a combination of axial and circumferential holes may be used. Also, different configurations of inflation chambers114in the airbag cushion102(as seen inFIGS. 12(A) and 12(B)) are contemplated. Furthermore, according to another embodiment, the airbag device may be placed in the sitting pad16in a fashion similar to the embodiment in which the assembly is placed in the back support14(as seen inFIG. 1).

The disclosed airbag is the first to be designed to function as both a curtain and a side airbag in the environment of a bus (such as a school bus) or a motor coach. The airbag module is designed to allow FMVSS 222 seat articulation without interfering with the occupant protection or the energy-absorbing capacity of either the seat or the airbag.

The disclosed airbag device and vehicle may provide one or more of the following benefits: (1) the device may balance employment loading/breakout forces such that a full-sized occupant is protected such that the Insurance Institute for Highway Safety (IIHS) “Technical Working Group” out-of-position occupant test protocols are satisfied; (2) the side deployment of the airbag device applies less force on the head and neck of the vehicle occupant than the traditional curtain airbag; (3) the airbag device is designed in such a way as to allow an occupant to sit comfortably without reducing the effectiveness of either the airbag or the seat structure in a crash event; (4) the airbag cushion is designed to be a taller and wider side airbag which provides protection to the occupant's pelvis/torso as well as head/shoulders in addition to protecting the occupant in a rollover; (5) a rapidly-deployed airbag cushion with a directional fold allows the airbag device to provide restraint quickly even though buses exhibit a smaller distance between a properly-seated occupant and the exterior of the bus than that which exists for passenger cars; (6) by incorporating the fill tube which routes gas into the airbag cushion, and using an inflator with an appropriate size-to-performance ratio, the required airbag cushion pressures and inflation times can be met without comprising the seat design; (7) the number and the severity of injuries in accidents involving buses, especially head and thorax injuries may be reduced; (8) occupant ejection through a bus window by providing a combination of early restraint (absorbing an occupant's energy earlier in a crash event) and at least partially covering the window glass will be effectively reduced; and (9) the airbag being deployed between the occupant and the window to push him or her inward and away from the side impact may prevent an occupant from being struck from above or between caught between the cushion and the window.

Furthermore, in view of the fact that people of a wide variety of sizes currently ride in buses today (such as children and adults of various sizes), and could occupy any seating position, the disclosed airbag device may be robustly designed to comply with the out-of-position (“OOP”) child testing protocols developed by the IIHS-sponsored Technical Working Group (“TWG”) to demonstrate that a minimum risk to smaller seat occupants exists when the disclosed airbag is deployed.