Abstract:
A vehicle system for aiding in the protection of a vehicle occupant is disclosed. The system includes a seat assembly having a seat base and a seat back and a pelvic bolster rotatably attached to the seat back of the seat assembly. The pelvic bolster is rotatably movable between a first stowed position and a second deployed position. A reversible motor drives the pelvic bolster between its stowed position and its deployed position. The system further includes a threat condition sensor operatively associated with the reversible motor.

Description:
TECHNICAL FIELD 
       [0001]    The disclosed invention relates generally to pelvic bolsters for vehicle seats. More particularly, the disclosed invention relates to a seat mounted reversible pelvic bolster which is movable between a stowed position and a deployed position in response to a detected threat condition. 
       BACKGROUND OF THE INVENTION 
       [0002]    Side impact events in vehicles have been identified as one of the top priorities for both research and regulation with government requirements continuing to become more stringent. Continued development and progress in side impact systems has significant real world benefit. Current systems primarily use airbags and static door bolsters to promote early occupant contact and to limit forces transmitted to the occupant. Early engagement of the pelvis has been shown to be an effective side impact strategy. Traditional pelvis side impact airbags design for this purpose have limitations in achieving optimal stiffness, coverage and positioning due to challenges associated with deployment in very narrow spaces (&lt;3-4 inches) and within extreme timing constraints (&lt;5-10 ms). Conversely, static pelvic door bolsters are limited in their effectiveness to provide early engagement of the pelvis because they rely on door intrusion to bring the surface of the bolster in contact with the pelvis. 
         [0003]    The introduction of pre-crash sensor systems poses opportunities for improvement to deploy traditional side airbags. However, in order to take full advantage of the additional time afforded by pre-crash sensors, a decision to deploy may need to be made with less than 100% confidence of an event. In this situation, traditional airbags again have limitations as they are not reversible or resettable in the event they are deployed pre-crash for an impact that does not actually occur. 
         [0004]    Accordingly, as in so many areas of vehicle technology, there is room in the art of pelvic bolster design for an alternative configuration to known pelvic bolster structures which provides effective protection that can be adapted to a variety of shapes while maintaining relatively low manufacturing and assembly costs. 
       SUMMARY OF THE INVENTION 
       [0005]    The disclosed invention represents advancement in the art of vehicle safety systems. The disclosed invention provides a system for aiding in the protection of a vehicle occupant. The system includes a seat assembly having a seat base and a seat back and a pelvic bolster rotatably attached to the seat back of the seat assembly. The pelvic bolster is rotatably movable between a first stowed position and a second deployed position. A reversible motor drives the pelvic bolster between its stowed position and its deployed position. The system further includes a threat condition sensor operatively associated with the reversible motor. The seat back includes a recessed region for substantially receiving the pelvic bolster when in its stowed position. 
         [0006]    The pelvic bolster includes a first end pivotably attached to the seat back and a second end. When the pelvic bolster is in its stowed position the second end of the bolster generally points toward the roof of the vehicle. When the pelvic bolster is in its deployed position the second end of the bolster generally points vehicle forward, thus providing protection between the vehicle seat and the vehicle door trim. 
         [0007]    Other advantages and features of the invention will become apparent when viewed in light of the detailed description of the preferred embodiment when taken in conjunction with the attached drawings and the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    For a more complete understanding of this invention, reference should now be made to the embodiment illustrated in greater detail in the accompanying drawings and described below by way of examples of the invention wherein: 
           [0009]      FIG. 1  illustrates a side view of a an embodiment of the seat mounted movable pelvic bolster according to the disclosed invention illustrating the bolster in its deployed position; 
           [0010]      FIG. 2  illustrates a side view of another embodiment of the seat mounted movable pelvic bolster according to the disclosed invention illustrating the bolster in its stowed position; 
           [0011]      FIG. 3  illustrates the same view as that shown in  FIG. 2  but shows instead the pelvic bolster in its deployed position; 
           [0012]      FIG. 4  is a perspective view of the view shown in  FIG. 3 ; and 
           [0013]      FIG. 5  is a diagrammatic front view of the reversible pelvic bolster of the disclosed invention in relation to a vehicle door trim and an impacting force. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0014]    In the following figures, the same reference numerals are used to refer to the same components. In the following description, various operating parameters and components are described for one constructed embodiment. These specific parameters and components are included as examples and are not meant to be limiting. 
         [0015]    Several technologies exist to provide the same general function of provided early pelvis engagement in side impacts. Many of these existing technologies are mounted in the door trim and structure. Door mounted side impact technologies have limitations on the position and coverage of the countermeasure to the occupant due to the multitude of occupant sizes and seating positions along the seat track. In general, the solution presented by the disclosed invention as shown in the various figures and as discussed in relation thereto offers advantages over other technologies because it is resettable and because it maintains the same position and coverage relationship to the occupant, being mounted to the seat and not the door trim. 
         [0016]    With particular reference to  FIGS. 1 through 4 , a reversible pelvic bolster seating system, generally illustrated as  10 , is shown. The system  10  includes a vehicle seat  12  which includes a vehicle seat back  14  and a vehicle seat base  16 . It is to be understood that the vehicle seat  12  is only provided for illustrative purposes and is thus not intended as being limiting. The system  10  of the disclosed invention may find multiple applications, such as use in conjunction with vehicle bench seats (not shown). 
         [0017]    The reversible pelvic bolster seating system  10  includes a reversible (and resettable) side impact pelvic bolster  18 . The pelvic bolster  18  includes a first end  20  which is pivotably attached to the vehicle seat  12  (preferably but not necessarily to the vehicle seat back  14 ) and a second end  22  generally opposite the first end  20 . 
         [0018]    The configuration of the reversible pelvic bolster  18  may be generally an elongated oblong shape as shown in  FIG. 1  or may have a more oval shape as shown in  FIGS. 2 ,  3  and  4  as a reversible pelvic bolster  18 ′. In any event, the general oblong shape of the reversible side impact pelvic bolster  18  as illustrated is a preferred shape due to the rotational deployment path and the package space available for this particular embodiment, but it is to be understood that other shapes may be adapted while still providing an effective absorber of pelvic loads under lateral crash conditions. 
         [0019]    With reference to  FIGS. 2 ,  3  and  4 , the pelvic bolster  18 ′ includes a first end  20 ′ attached to the vehicle seat  12  (preferably but not necessarily to the vehicle seat back  14 ) and a second end  22 ′ generally opposite the first end  20 ′. As shown in  FIG. 2 , the pelvic bolster  18 ′ is in its stowed or generally upright position with respect to the vehicle seat back  14 . In the event of a sensed impact, the pelvic bolster  18 ′ is rotated forward to its deployed position as shown in  FIGS. 3 and 4 . In this position the pelvic bolster  18 ′ is positioned generally between the occupant&#39;s pelvic area and the vehicle door (not shown). 
         [0020]    Regardless of the shape of the reversible pelvic bolster as illustrated in the figures, its general function is the same. Particularly, the occupant protection strategy behind side impact tends to promote early engagement combined with load limiting, in order to reduce potentially injurious peak forces. The reversible side impact pelvic bolster  18  (or  18 ′ as the case may be) may enhance occupant performance in side impacts by enabling positioning of a countermeasure prior to impact for improved occupant coverage/positioning and improved control of strength/stiffness characteristics. By nature of its shape, size and location, the reversible side impact pelvic bolster  18  fills the empty space between an occupant&#39;s pelvis and the door trim (as shown in  FIG. 5  and discussed in relation thereto), enabling early engagement of the pelvis. The reversible nature of this technology allows for conservative deployment thresholds for maximum benefit with minimal risk/inconvenience because the reversible side impact pelvic bolster  18  automatically resets itself to the design position once a threat condition has passed. 
         [0021]    Referring to  FIG. 5 , a diagrammatic front view of the reversible pelvic bolster seating system  10  is illustrated in relation to a vehicle door and an impacting force “F.” 
         [0022]    A motor  30  is provided to move the reversible side impact pelvic bolster  18  between the stowed position shown in  FIG. 2  and the deployed position shown in  FIGS. 1 ,  3 ,  4  and  5 . The motor  30  includes a motor drive shaft  32 . Due to the package space and occupant seating comfort, a  4 -bar linkage (not shown) may be used to connect the motor drive shaft  32  with the reversible side impact pelvic bolster  18 . However, it is to be understood that the reversible pelvic bolster seating system  10  may alternatively rely up the seat recline motor located in the same general vicinity as the motor  30  required to power the reversible pelvic bolster  18 . The seat  10  is shown in relation to a vehicle door trim  34  and an outer door sheet metal  36 . A pelvic bolster  38  is provided between the vehicle door trim  34  and the outer door sheet metal  36  as is known in the art. 
         [0023]    Upon a voltage signal from a seat controller ECU  42 , the reversible side impact pelvic bolster  18  will rotate into position so that the bolster  18  will be pre-deployed prior to impact. If an impact occurs, the reversible side impact pelvic bolster  18  will provide early contact to the occupant, providing a more effective pelvic push and reducing peak forces. CAE modeling showed that loading the pelvis early could reduce the peak pelvic loads by ˜39%. 
         [0024]    In addition to its described function to absorb pelvic loads during a side impact event, the reversible side impact pelvic bolster  18  can also serve as an armrest when in its deployed position as shown in  FIGS. 1 ,  3  and  4 . As most clearly illustrated in  FIG. 3 , the top of the reversible side impact pelvic bolster  18  is at an acceptable height for an armrest. This surface can be used by an occupant (not shown) as the armrest. If it is desired that the reversible side impact pelvic bolster  18  be used as an armrest, an arrangement would be required such that the operator could selectively effect movement of the reversible side impact pelvic bolster  18  by such means as a switch which would override the deployment system and specifically the voltage signal from the seat controller ECU  42 . 
         [0025]    The reversible side impact pelvic bolster  18  is intended to deploy when a threat condition is detected. Detection of threat conditions may be made with sensor information from existing technologies (RSC or high yaw) or with future sensor technologies (radar, CV sensors, camera, etc.). The reversible nature of this technology allows for conservative deployment thresholds for maximum benefit. Unlike conventional airbags, the reversible side impact pelvic bolster  18  will retract into its stowed position after the threat passes. Should an occupant be Out-Of-Position (OOP), the reversible side impact pelvic bolster  18  will contact the occupant and retract. 
         [0026]    The reversible pelvic bolster seating system  10  disclosed herein provides an early pelvic push, lowering peak load on the occupant. The reversible pelvic bolster seating system  10  uses available motors and fastening locations, thus minimizing assembly cost and time. 
         [0027]    The foregoing discussion discloses and describes an exemplary embodiment of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the true spirit and fair scope of the invention as defined by the following claims.