Seat mounting structure for mitigating injury in side impacts

A seat mounting structure is disclosed for reducing injury to vehicle occupants in side impact collisions. The seat mounting structure may include an inflation module, a linkage system, a sensor system, and a side airbag. The inflation module may include an inflatable structure and inflator or a piston device. The linkage system attaches the seat mounting structure to a seat and may help guide the movement of the seat. The sensor system may include a radar sensor and an optical sensor to help the sensor system anticipate an impending side impact. The seat mounting structure mitigates injury to the occupant by moving the occupant vertically up and laterally toward a centerline of the vehicle, thus increasing the space between the sidewall of the vehicle and the occupant. Additionally, the inflation module may comprise an inflatable structure that stiffens a floor structure of the vehicle upon inflation.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to systems and methods for reducing injury to occupants during a side impact collision. More specifically, the present invention relates to displacing vehicle occupants away from and reinforcing the vehicle against intrusion in side impacts.

2. Description of Related Art

The inclusion of inflatable safety restraint devices, or airbags, is now a legal requirement for many new vehicles. Airbags are typically installed in the steering wheel and in the dashboard on the passenger side of a car. Additionally, airbags may be installed to inflate beside the passenger to provide side impact protection, in front of the knees to protect the knees from impact, or at other strategic locations.

Despite the development of side airbags, problems still remain in the area of side impact protection. For instance, insufficient space for side airbags to decelerate and cushion vehicle occupants is a continuing problem. Additional problems with side impact protection include the lack of strength in the vehicle sidewall, the close proximity of an occupant to the impact zone, and the higher likelihood of intrusion by the impacting vehicle into the occupant compartment of the vehicle.

These problems are compounded by differences in vehicle characteristics between the impacting vehicle and the target vehicle. Some of these characteristics include weight differences, geometry differences, differences in stiffness, and particularly differences in height off the ground. Vehicle compatibility becomes a concern when the impacting vehicle and the target vehicle are mismatched, for instance, when a larger SUV (sport utility vehicle, light truck, or van) impacts a smaller compact car.

In a mismatched collision, the smaller target vehicle undergoes a higher velocity change, and has less structure to absorb the impact energy. In a mismatched side impact, the larger striking vehicle is elevated with respect to the smaller target vehicle causing the brunt of the impact to be absorbed by the passenger compartment of the target vehicle, rather than striking the target vehicle's horizontal base member, or sill.

Since the side of the passenger compartment is often less stiff than the striking car's front, the side of the target vehicle is deformed into the passenger compartment. The smaller target vehicle potentially has less interior space to mitigate this effect of intrusion into the passenger compartment and the impact of the striking vehicle can hit the occupant of the target vehicle at speeds approximating the initial speed of the striking vehicle. The occupants of the target vehicle are severely endangered thereby.

A recent analysis of crash data reveals that larger SUV-to-car collisions produce a significantly higher rate of fatalities than car-to-car collisions. For example, when SUVs strike passenger cars on the left side, the risk of death to the car driver is five times higher than the risk associated with a car-to-car left side impact collision. The recent increase in the percentage and number of larger vehicles, such as SUVs, currently operating has exacerbated this problem.

To counteract these problems, some vehicle protection systems have been developed to move the occupant and increase the distance between the occupant and the vehicle sidewall. These systems include moving the occupant laterally or tilting the seat away from the impact area.

However, these methods have not fully solved the problems described above. For instance, many vehicles have a hump in the middle of the vehicle that prohibits lateral motion. Tilting the seat accelerates the occupant's head toward the middle of the vehicle, which acceleration may injure the occupant. In addition, neither method protects the occupant against intrusion into the occupant compartment of the vehicle. Neither method provides an answer to the increased risks associated with a high profile vehicle impacting a low profile vehicle.

SUMMARY OF THE INVENTION

The apparatus and method of the present invention have been developed in response to the present state of the art, and in particular, in response to the problems and needs in the art that have not yet been fully solved by currently available occupant protection devices. In accordance with the invention as embodied and broadly described herein in the preferred embodiment, a novel side impact protection system is provided. The side impact protection system is a seat mounting system that comprises an anticipatory sensor system, an inflation module, and a linkage system.

The inflation module may comprise an inflator and one or more inflatable structures. The inflation module may perform two tasks: displacing the seat and stiffening a floor structure of the vehicle. The first task is performed by mounting the seat on top of an inflatable structure, which displaces the seat vertically and/or laterally when the inflatable structure inflates. Moving the occupant vertically upward is important because this allows the seat to move laterally toward the center of the vehicle without obstruction by the middle hump. This movement also lessens the likelihood of direct contact by the intruding sidewall into the occupant's vital areas. The second task is performed when the inflatable structure is inflated and stiffens the floor structure. A stiffened floor structure inhibits intrusion into the occupant compartment of the vehicle.

The linkage system operates in combination with the inflation module. As the inflatable structure is inflated, the linkage system harnesses the vertically upward motion of the inflating inflatable structure to guide the seat vertically up and laterally toward a centerline of the vehicle. Alternatively, if the inflatable structure moves the seat laterally, then the linkage system may harness the lateral motion and guide the seat vertically upward.

The sensor system may be an anticipatory sensor system such as those known in the art. The sensor system may comprise at least one sensor, an electronic control unit, and electrical connectors that connect components of the sensor system. The sensor system may detect a side impact and/or an impending side impact. When an impending side impact is detected, the sensor system initiates the inflation module. A sensing system may be included to detect an impending collision. Such sensing systems may include optical sensors utilizing lasers, microwaves or infrared sensors. Radar sensors or ultrasonic sound wave sensors may be employed. An accelerometer for measuring heavy deceleration may also be used. When a radar sensor is used, a radar antenna sends out a short, tightly focused, high-power pulse of radio waves at a known frequency. When the waves hit an object, they echo off of it and the speed of the object Doppler shifts the echo. The antenna receives the returning signals and the signals are analyzed by an electronic control unit to determine if there is an impending side impact. If the electronic control unit determines that a side impact is impending, the electronic control unit will actuate the inflation module and possibly a side airbag system.

In one exemplary embodiment, the linkage system comprises two bars, each with one end pivotally fixed in relation to the floor structure. The other end is pivotally attached to a seat mount. The seat mount is also attached to a seat adjustment structure and slidably attached to a track mounted on top of the inflatable structure. The seat adjustment structure may be a standard structure that allows an occupant to adjust their seat for comfortable positioning within the vehicle. The track allows the seat mount to slide laterally on the inflatable structure.

The linkage system maintains the seat mount, and therefore the seat, in place until the inflatable structures are inflated. Once inflation begins, the bars pivot to guide the seat about a circular path, which guides the seat laterally toward the centerline of the vehicle and vertically up. The seat mount, and therefore the seat, has the added advantage of being uniformly displaced in curvilinear translation such that little or no tilting of the seat takes place. In other words, the front, back, and each side is displaced and guided substantially at the same rate by the inflation module and the linkage system so that the seat remains at the same general orientation as before inflation.

Alternative embodiments may be used that vary the linkage system and/or the inflation module. For instance, the linkage system may comprise one bar instead of two, or a plurality of bars. The inflation module may comprise a piston device actuated by a gas generant having a piston that displaces a seat vertically up and laterally toward the centerline of the vehicle. The linkage system may comprise a seat mount slidably attached to a rail that supports the movement of the seat vertically up and laterally toward the centerline of the vehicle.

Some advantages of the invention include moving a vehicle occupant up over obstacles that impede lateral movement and stiffening the floor structure to reduce intrusion in the occupant compartment of the vehicle. Obstacles may include vehicle structures, such as the ridge that extends down the middle of the vehicle. Therefore, the occupant is able to move further away from the impact side of the vehicle. These and other features and advantages of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention utilizes a number of physical principles to enhance the protection of vehicle occupants in a side impact collision. For example, a linkage system converts a portion of vertical motion into lateral motion or a portion of lateral motion into vertical motion. An elongated metal inflatable structure, upon inflation, increases the mass moment of inertia of the inflatable structure, making the inflatable structure stiffer and less likely to fail in buckling or bending. Furthermore, the orientation of an inflatable structure to a side impact affects how the impact energy is applied to the inflatable structure. How the impact energy is applied dictates how much impact energy may be resisted and absorbed by the inflatable structure.

Such principles may be applied to many types of inflatable structures and linkage systems, including airbags, metal inflatable structures, four bar mechanisms, tracks, and rails. An illustrative manner in which the present invention utilizes these principles to provide side impact protection will be shown and described in greater detail with reference toFIGS. 1 through 5.

For this application, the phrases “connected to” and “coupled to” refer to any form of interaction between two or more entities, including mechanical, electrical, magnetic, electromagnetic, and thermal interaction. The phrase “attached to” refers to a form of mechanical coupling that restricts relative translation or rotation between the attached objects. The phrases “pivotally attached to” and “slidably attached to” refer to forms of mechanical coupling that permit relative rotation or relative translation, respectively, while restricting other relative motion. The phrase “attached directly to” refers to a form of attachment by which the attached items are either in direct contact, or are only separated by a single fastener, adhesive, or other attachment mechanism.

FIG. 1illustrates a cutaway, front elevation view of a seat mounting structure for mitigating injury in side impacts within the scope of the invention. As shown, an occupant10is seated in a seat12of the vehicle14and restrained by seat belt16. The seat belt16may be integral with the seat12and is designed to restrain the occupant10on the seat12when the seat12is displaced in accordance with the invention. The seat12also comprises a seat adjustment structure18that allows the seat to be adjusted forward and backward for the comfort of the occupant.

FIG. 1has three directions depicted for clarification of movement related toFIGS. 1,2, and3. The directions depicted are lateral20, vertical22, and transverse24. Additionally, a centerline26is depicted as a line disposed midway between two vehicle sidewalls28. The vehicle sidewalls28also help define an occupant compartment29within the vehicle14.

Also shown inFIG. 1, the seat12is attached to a seat mounting structure30, which is attached to the vehicle14. The seat mounting structure30connects the seat12to a floor structure48. The seat mounting structure30comprises a linkage system32, an inflation module34, and sensor system36. The linkage system32guides the motion of the seat12vertically22up and laterally20toward the centerline26of the vehicle14. The sensor system36detects an impending side impact and initiates the inflation module34. Once initiated, the inflation module34proceeds to displace the seat12vertically22upward.

The linkage system32shown inFIGS. 1 and 2comprises a seat mount38, two tracks40, and two bars42each having a first pivot44on one end and a second pivot46on the other end. The seat mount38is the structure upon which the seat is mounted. The structure of the seat mount38can vary depending on the make and model of the vehicle and the characteristics of a seat. The seat mount may comprise holes in different parts of the seat mounting structure30, parts that are connected to the seat adjustment structure18, or a bracket for attaching the seat adjustment structure18or seat12to the seat mounting structure30.

The seat mount38is attached to the seat adjustment structure18and is slidably attached to the tracks40. Each track40is attached to a top of inflatable structures50and51of the inflation module34. Each track40allows the seat mount38to be slidably attached to seat mounting structure30, thereby allowing lateral20movement of the seat12. Lateral20movement of the seat12is controlled by the bars42. The first pivots44of the bars42are pivotally attached to the seat mount38. The second pivots46of the bars42may be pivotally attached to bottom portion of the inflation module34. The second pivots46may instead be pivotally attached to a floor structure48of the vehicle14. Generally, the second pivots46are disposed in a fixed location with respect to the vehicle14.

The inflation module34comprises a first inflatable structure50, a second inflatable structure51(shown inFIG. 3), connecting tubes52, and an inflator54. The second inflatable structure50sin this embodiment is an elongated metal structure, each having two folded sidewalls56. The top wall58of the inflatable structure50may have a wall thickness of about 0.06 inches. The wall thickness of the inflatable structure50preferably ranges from 0.04 to 0.06 inches, though the wall thickness may be thicker or thinner.

The inflatable structures50and51are oriented laterally20with the first inflatable structure50positioned under a front portion of the seat12. A second inflatable structure51(shown inFIG. 3) is positioned under a rear portion of the seat12. The inflatable structures50and51are directly attached to the floor structure48of the vehicle14. The connecting tubes52connect the inflatable structures50and51to the inflator54. The inflator54may be attached to the floor structure48of the vehicle14. The inflator54may be positioned anywhere in the vehicle14and may actually be positioned to directly inflate the inflatable structures50and51without the need of connecting tubes52.

In addition to the elongated metal inflatable structures50and51, several other types of inflatable structures may also be used. For instance, a single airbag or metal structure may be used in place of both inflatable structures50and51. Additional elongated metal structures may also be used.

The sensor system36may be attached to the inflator54via a first set of wires60. The first set of wires60comprise a first end connected to the inflator54and a second end connected to an electronic control unit62. A second set of wires64comprises a first end connected to the electronic control unit62and a second end connected to the sensors66. It will be appreciated that the inflator54, electronic control unit62, and sensors66may be connected using wireless electronic connectors known in the art.

The sensors66may comprise a radar sensor, an optical sensor, or other sensors capable of detecting an impending side impact or an actual side impact. A radar sensor sends out a short, tightly focused, high-power pulse of radio waves at a known frequency. When the waves hit an object, such as another vehicle, they echo off of it and the speed of the object Doppler shifts the echo. The radar sensor receives the returning signals and determines whether a collision is imminent.

Optical sensing systems may be employed for detecting an impending side impact. A specific example of an optical sensor is lidar (light detection and ranging). With lidar, a very short burst of infrared laser light is emitted and its reflection is detected, thus determining the distance from the approaching vehicle. By taking thousands of samples per second, the change in distance indicates the location and speed of the oncoming vehicle. Other sensing systems such as ultrasonic sound wave sensors, optical microwave sensors, or an accelerometer for measuring heavy deceleration could also be employed.

The electronic control unit62analyzes the signals sent by the sensors66to determine if a side impact has occurred or is likely to occur. Preferably, an anticipatory sensor system is used, wherein the sensors66are able to sense the surrounding environment of the vehicle14and the electronic control unit62is able to determine if a side impact is likely to occur. Once the electronic control unit62determines that a side impact is occurring or is likely to occur, the electronic control unit62actuates the inflator54to inflate the inflatable structure. Being able to anticipate a side impact prior to the actual impact has the benefit of giving the vehicle safety systems more time to prepare the safety measures to better protect the vehicle occupant10.

In addition to the sensor system described above, seat mounting structure30may also be used with in-seat weight sensors and occupant position sensors. These additional sensors can be used to better deploy the safety systems by detecting the size and location of the occupant10in relation to the seat.

The seat mounting structure30described above mitigates injury from side impacts in the following manner. First, the sensors66detect a side impact or an impending side impact, if anticipatory sensors are used. Second, the signal from the sensors66is sent to the electronic control unit62via the second set of wires64. Third, the electronic control unit64determines that an impact has occurred or is likely to occur and sends an initiation signal to the inflator54via the first set of wires60.

Fourth, the inflator54is actuated to inflate the inflatable structures50and51via the connecting tubes52. Fifth, the inflatable structures50and51inflate and raise the seat vertically22upward. Sixth, as the seat mount38is displaced vertically22upward, and the linkage system32moves the seat laterally20toward the centerline26. According to the linkage system32illustrated inFIGS. 1–3, the bars42pivot and pull the seat mount38on the track40laterally20toward a centerline26of the vehicle14. Therefore, the seat12connected to the seat mount38moves both vertically22upward and laterally20toward the centerline26of the vehicle14. This method effectively moves the occupant10away from the side impact and up so that the occupant's10vital organs are less exposed to the force of the impact.

The inflatable structures50and51may also be configured to provide additional protection to the occupant10. This may be accomplished by designing the inflatable structures in a manner such that they stiffen and strengthen the floor structure48. For example, the inflatable structures may comprise an elongated metal structure with folded sidewalls. These inflatable structures50and51may be used alone or in conjunction with other configurations of this invention. When inflated, the inflatable structures50and51stiffen the floor structure48around the seat12of the occupant10and a lower portion of a side of the vehicle14. These inflatable structures50and51may reduce intrusion of an impacting vehicle80into the occupant compartment29of the vehicle14, especially around the seat of the occupant.

The inflatable structures50and51are preferably laterally20oriented and attached to the floor structure48of the vehicle14. Inflation of the inflatable structures50and51increases the mass moment of inertia of the inflatable structures, thus increasing the stiffness of the inflatable structures50and51and the floor structure48. Furthermore, the internal pressure of the inflated structure additionally helps prevent deformation of the inflatable structures50and51. This enhances their ability to reinforce the floor structure48. As explained above, the placement of the inflatable structures50and51under the seat12of the occupant10also provides a means for displacing the seat12. Though the stiffening protection detailed above would not be available with other inflatable structures, such as ordinary airbags, other inflatable structures may be used to displace of the seat12vertically22upward and laterally20toward the centerline26.

Finally, the lateral20positioning of the inflated structures50and51is an improvement over transverse24positioning because lateral20positioning of the inflatable structures allows an area around the occupant10to be better protected against intrusion than just reinforcing a vehicle side wall28transversely24. Additional laterally20oriented inflatable structures designed to stiffen a floor structure of the vehicle14may be positioned in front of or behind the seat12for added protection.

FIG. 2shows a cutaway, front elevation view of the seat mounting structure ofFIG. 1, wherein the inflatable structures50and51are fully inflated. As shown, the bars42of the linkage system32have pivoted such that the seat12has been guided laterally20on the track40as a result of the vertically22upward displacement of the seat12by the inflatable structures50and51. Also, the movement of the seat12approximates curvilinear translation, wherein each corner of the seat12is moving on parallel paths at approximately the same rate such that the orientation of the seat12and occupant10remains substantially unchanged through out the translation of the seat12.FIG. 2shows a side impact is about to occur, with the impacting vehicle80close to the vehicle14.

Referring toFIGS. 3A,3B, and3C, a side elevation cutaway view of the seat mounting structure ofFIG. 1illustrates inflation of the inflatable structures50and51in an original folded state, a half inflated state, and fully inflated state, respectively. As shown inFIG. 3A, the inflatable structures50and51are substantially flat in their folded state.FIG. 3Bshows the inflatable structures50and51half inflated, andFIG. 3Cshows the inflatable structures50and51fully inflated. The folded sidewalls56allow the top wall58of the inflatable structures50and51to support the track40of the linkage system32by providing an area of the inflatable structures50and51that does not deform when the inflatable structures50and51are inflated.

Referring toFIG. 4, an alternative embodiment of the invention is shown in a cutaway, front elevation view. LikeFIGS. 1 through 3, a seat112is shown in a vehicle114. The seat112comprises an integrally formed seat belt116and a seat adjustment structure118that allows an occupant to adjust the seat112for their comfort within the vehicle114.

The directions within the vehicle are laterally120, vertically122, and transverse124and are shown in the Figure. A centerline126of the vehicle114is shown as an imaginary line drawn midway between the vehicle sidewalls128. The vehicle114also comprises a occupant compartment129disposed between the vehicle sidewalls128.

The seat mounting structure130comprises a linkage system132, an inflation module134, and sensor system136. The linkage system132in this embodiment comprises a seat mount138, a rail140, and a slider142. The seat mount138is attached to the seat adjustment structure118. A rail142is attached to a floor structure148of the vehicle114. A slider142is connected to the seat mount138and is slidably attached to the rail140.

The inflation module134comprises a piston device150. The piston device150is preferably a gas generant actuated device, wherein a gas generant is stored within the piston device150. When the piston device is initiated by the sensor system, the gas generant reacts to form a gas that expands and pushes the piston head152out of the piston housing154. The piston head152is connected to the seat mount138so that movement of the piston head152results in displacement of the seat. In this embodiment, the piston device150is mounted on an angle that is substantially identical the angle the rail140is mounted. Therefore, the displacement of the seat112by the piston device150is supported by the rail140.

The piston device150may also take many forms and configurations. For instance, the piston device may have a piston head that moves on the outside of the piston housing. Also, the piston device may alternatively be actuated by an internally stored pressurized liquid or an external inflator. The inflator may contain a pressurized liquid, a gas generant, or a combination of both. It should also be apparent from this disclosure that any number of the inflatable structures may be used to displace the seat, including a single inflatable structure.

The piston device150is initiated through a first set of wires160by an electronic control unit162of the sensor system136. The electronic control unit162interprets signals provided through a second set of wires164from the sensors166to determine if there has been a side impact or if there is an impending side impact.

The sensor system136may also be electronically connected to a side airbag system170to enhance the protection of an occupant in side impacts. Combining a conventional side airbag system170with the seat mounting structures30and130detailed above provides more occupant protection by moving the seat112away from the impact and provide added padding that results from use of the side airbag system170.

A side airbag within the meaning of this disclosure includes any inflatable structure that is inflated between a seat and a vehicle sidewall. The term side airbag may include both a side airbag and inflatable curtains. Additionally, a side airbag may be mounted in a variety of locations known in the art. A side airbag may be mounted in the seat or in the roof rail of a vehicle. An advantage provided by this invention is that a side airbag may be bigger to take advantage of the extra available space, after movement of the seat to provide more protection to a vehicle occupant.

FIG. 5shows the seat mounting structure130ofFIG. 4with the piston head152fully extended from the piston housing154. As shown, the seat112has been moved vertically122up and laterally120toward the centerline126of the vehicle114. In addition, the side airbag172has been deployed between the vehicle sidewall128and the seat112.

From this disclosure, it would also be apparent to one skilled in the art that piston devices could be used alone to displace the seat112vertically122up and laterally120toward the centerline126of the vehicle114. In that configuration, the linkage system would only be a seat mount as described above. In addition, inflatable structures that stiffen the floor structure148of the vehicle114may also be used in combination with piston devices to further protect the occupant from injury.

Those skilled in the art will appreciate that other configurations may be used to displace the seat vertically up and laterally toward the centerline. For example, one alternative configuration (not shown) of the invention uses a piston device that is vertically oriented. As the seat is displaced vertically up, a linkage system guides the seat laterally toward the centerline of the vehicle. The linkage system comprises a seat mount, a curved rail, and a track. The curved rail is slidably attached to the seat mount, and connected to a floor structure of the vehicle. The piston head is connected to the track and the track is slidably attached to the seat mount.

Of course, an alternative linkage system comprising a seat mount, bars, and a track may also be used with this configuration to guide the seat laterally toward the centerline of the vehicle. The bars may have one end pivotally connected to the floor structure of the vehicle and the other end connected to the seat mount.

Another alternative configuration orients the piston device laterally. As the piston head moves laterally toward the centerline of the vehicle, the seat mount is forced to slide on a rail vertically up and laterally toward the centerline of the vehicle. The piston head may be connected to a vertically oriented track with the track slidably attached to the seat mount. The track allows the seat to move in curvilinear translation.

The seat mounting structures described above are simply examples. The inflator design, linkage system, and inflation module requirements may be modified as needed to perform the functions described herein. Many other inflator designs, linkage systems, and inflation modules may be created within the scope of the present invention by combining, isolating, or otherwise modifying the features depicted in the figures.

The airbag modules and associated methods of the present invention improve vehicle safety systems related to side impacts. Through the use of inflatable structures, a seat may be displaced up and away from a side impact and a floor structure of a vehicle may be stiffened to help reduce intrusion in the occupant compartment of the vehicle. In addition, the seat may move over obstacles such that the seat may move farther laterally than otherwise possible. Anticipatory sensors allow the occupant to be moved before an impact takes place. The extra time and space allows a side airbag to be deployed that is able to more effectively decelerate and cushion the occupant.