Patent Publication Number: US-2023159110-A1

Title: Vehicle Center Pillar Structure

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of Korean Patent Application No. 10-2021-0160554, filed on Nov. 19, 2021, which application is hereby incorporated herein by reference. 
     TECHNICAL FIELD 
     The present disclosure relates to a vehicle center pillar structure. 
     BACKGROUND 
     A side impact test introduced by the Insurance Institute for Highway Safety (IIHS) is designed to simulate an actual car in side crashes and reproduce real field accidents. In the IIHS side impact test, which is scheduled to be revised in 2022, the weight and strength of a moving deformable barrier (MDB) striking a vehicle body will be further increased. Accordingly, it is necessary to improve the overall stiffness and strength of the vehicle to sufficiently respond to the IIHS side impact test revisions. 
     A vehicle center pillar is designed to provide structural stiffness of the vehicle body and to improve crash performance and roof strength, thereby protecting a passenger compartment. 
     A lower portion of the center pillar may be joined to a side sill using fasteners, welding, and/or the like. During a side collision of the vehicle, an impact load may concentrate on a joint portion between the lower portion of the center pillar and the side sill, and the joint portion between the lower portion of the center pillar and the side sill may be excessively deformed (bent) by the impact load. Some overlapping portions between the lower portion of the center pillar and the side sill may be joined by spot welding. In order to increase stiffness and strength with respect to the joint portion between the lower portion of the center pillar and the side sill, a pillar reinforcement may be mounted in the lower portion of the center pillar, and a plurality of bulkheads may be mounted in a cavity of the side sill. 
     In the event of a side collision, however, the joint portion between the lower portion of the center pillar and the side sill may be easily deformed, and the lower portion of the center pillar may be easily pushed into the passenger compartment. Accordingly, a battery and the passenger compartment may not be safely protected during the side collision of the vehicle. In particular, the weight and strength of the MDB in the IIHS side impact test to be revised in 2022 will be increased, and thus it is necessary to improve stiffness and strength with respect to the joint portion between the lower portion of the center pillar and the side sill. 
     The above information described in this background section is provided to assist in understanding the background of the inventive concept, and may include any technical concept which is not considered as the prior art that is already known to those skilled in the art. 
     SUMMARY 
     The present disclosure relates to a vehicle center pillar structure. Particular embodiments relate to a vehicle center pillar structure significantly improving side crash performance (crashworthiness). 
     Embodiments of the present disclosure can solve problems occurring in the prior art while advantages achieved by the prior art are maintained intact. 
     [ooio] An embodiment of the present disclosure provides a vehicle center pillar structure designed to increase stiffness and strength with respect to a joint portion between a lower portion of the center pillar and a side sill, thereby improving side crash performance (crashworthiness) of the vehicle. 
     According to an embodiment of the present disclosure, a vehicle center pillar structure may include a center pillar having a lower connection portion, a side sill having an intermediate connection portion to which the lower connection portion of the center pillar is joined, a pillar reinforcement joined to an inboard surface of the center pillar, and a side sill reinforcement joined to an inboard surface of the side sill. The pillar reinforcement and the side sill reinforcement may be joined to the intermediate connection portion of the side sill. Specifically, at least a portion of the intermediate connection portion of the side sill may be sandwiched between the pillar reinforcement and the side sill reinforcement. 
     The pillar reinforcement and the side sill reinforcement may be individually joined to the intermediate connection portion of the side sill, and the pillar reinforcement and the side sill reinforcement may be provided with at least a portion of the intermediate connection portion of the side sill sandwiched therebetween so that the pillar reinforcement and the side sill reinforcement may more firmly join the lower connection portion of the center pillar to the intermediate connection portion of the side sill. Thus, joint stiffness between the lower connection portion of the center pillar and the intermediate connection portion of the side sill may be significantly improved. 
     The pillar reinforcement may include a side wall joined to the lower connection portion of the center pillar, and a bottom flange joined to a top wall of the intermediate connection portion of the side sill. 
     The side wall of the pillar reinforcement may be joined to the lower connection portion of the center pillar, and the bottom flange of the pillar reinforcement may be joined to the top wall of the intermediate connection portion of the side sill so that the lower connection portion of the center pillar may be more firmly connected to the intermediate connection portion of the side sill through the pillar reinforcement. That is, the pillar reinforcement may increase connection stiffness between the lower connection portion of the center pillar and the intermediate connection portion of the side sill through the bottom flange. 
     The side sill reinforcement may be joined to the intermediate connection portion of the side sill. The intermediate connection portion may include an outboard side wall facing the exterior of the vehicle and the top wall facing the top of the vehicle. 
     Accordingly, the intermediate connection portion of the side sill may increase its own stiffness with the side sill reinforcement. 
     The side sill reinforcement may include a side wall joined to the outboard side wall of the intermediate connection portion and a top wall joined to the top wall of the intermediate connection portion. 
     At least a portion of the top wall of the intermediate connection portion may be sandwiched between the bottom flange of the pillar reinforcement and the top wall of the side sill reinforcement. 
     Thus, the bottom flange of the pillar reinforcement and the top wall of the side sill reinforcement may be firmly supported with respect to the top wall of the intermediate connection portion so that connection stiffness between the bottom flange of the pillar reinforcement and the top wall of the intermediate connection portion of the side sill may be improved. 
     The lower connection portion of the center pillar may include a lower outboard side wall joined to an outboard surface of the outboard side wall of the intermediate connection portion. The outboard side wall of the intermediate connection portion may be sandwiched between the lower outboard side wall of the lower connection portion and the side wall of the side sill reinforcement. 
     Thus, the lower connection portion of the center pillar and the side wall of the side sill reinforcement may be firmly supported with respect to the outboard side wall of the intermediate connection portion of the side sill so that connection stiffness between the lower connection portion of the center pillar and the intermediate connection portion of the side sill may be improved. 
     The vehicle center pillar structure may further include a plurality of bulkheads joined to the intermediate connection portion of the side sill and the side sill reinforcement. 
     Accordingly, the side sill reinforcement may connect the plurality of bulkheads in a longitudinal direction of the side sill, and the intermediate connection portion of the side sill may increase its own stiffness and strength with the plurality of bulkheads and the side sill reinforcement. 
     The lower connection portion may include a lower front wall facing the front of the vehicle and a lower rear wall facing the rear of the vehicle. 
     The pillar reinforcement may include a front wall joined to the lower front wall of the lower connection portion and a rear wall joined to the lower rear wall of the lower connection portion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects, features and advantages of embodiments of the present disclosure will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: 
         FIG.  1    illustrates a vehicle center pillar structure according to an exemplary embodiment of the present disclosure; 
         FIG.  2    illustrates an exploded perspective view of a vehicle center pillar structure according to an exemplary embodiment of the present disclosure; 
         FIG.  3    illustrates a perspective view of a state in which a pillar reinforcement is mounted on a center pillar in a vehicle center pillar structure according to an exemplary embodiment of the present disclosure; 
         FIG.  4    illustrates a perspective view of a state in which a side sill reinforcement is mounted on an intermediate connection portion of a side sill in a vehicle center pillar structure according to an exemplary embodiment of the present disclosure; 
         FIG.  5    illustrates a partially cut-away perspective view of a vehicle center pillar structure according to an exemplary embodiment of the present disclosure, which is viewed from the interior of the vehicle; and 
         FIG.  6    illustrates a cross-sectional view, taken along line A-A of  FIG.  1   . 
     
    
    
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals will be used throughout to designate the same or equivalent elements. In addition, a detailed description of well-known techniques associated with the present disclosure will be omitted in order not to unnecessarily obscure the gist of the present disclosure. 
     Terms such as first, second, A, B, (a), and (b) may be used to describe the elements in exemplary embodiments of the present disclosure. These terms are only used to distinguish one element from another element, and the intrinsic features, sequence or order, and the like of the corresponding elements are not limited by the terms. Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meanings as those generally understood by those with ordinary knowledge in the field of art to which the present disclosure belongs. Such terms as those defined in a generally used dictionary are to be interpreted as having meanings equal to the contextual meanings in the relevant field of art, and are not to be interpreted as having ideal or excessively formal meanings unless clearly defined as having such in the present application. 
     Referring to  FIGS.  1  to  3   , a vehicle center pillar structure  10  according to an exemplary embodiment of the present disclosure may include a center pillar  11  and a side sill  5  to which a lower portion of the center pillar  11  is joined. 
     The center pillar  11  may be a pillar which is located between a front seat and a rear seat. The center pillar  11  may extend vertically in the middle of a side opening of a vehicle body, and may be designed to respond to a side collision of the vehicle. 
     The center pillar  11  may include a center pillar outer facing the exterior of the vehicle, and a center pillar inner facing the interior of the vehicle. The center pillar  11  illustrated in  FIGS.  1 ,  2 ,  3 ,  5 , and  6    may be referred to as the center pillar outer, and the center pillar inner may be omitted. 
     The center pillar  11  may include a front wall  21  facing the front of the vehicle, a rear wall  22  facing the rear of the vehicle, and an outboard side wall  25  facing the exterior of the vehicle. The front wall  21  may be provided on a front edge of the outboard side wall  25 , and the rear wall  22  may be provided on a rear edge of the outboard side wall  25 . A front flange  23  may extend from the front wall  21  toward the front of the vehicle, and a rear flange  24  may extend from the rear wall  22  toward the rear of the vehicle. 
     The center pillar  11  may include a lower connection portion  13  provided on the lower portion thereof. The lower connection portion  13  may extend as one continuous piece from the center pillar  11  along a longitudinal direction of the center pillar  11 . That is, the lower connection portion  13  and the center pillar  11  may form a unitary one piece along the longitudinal direction of the center pillar  11 . Accordingly, an end face of the lower connection portion  13  may be continuous with respect to an end face of the center pillar  11  along the longitudinal direction of the center pillar  11 . A width of the lower connection portion  13  may gradually increase from a top end thereof toward a bottom end thereof. 
     The width of the lower connection portion  13  may be greater than that of a main body of the center pillar  11 , and the lower connection portion  13  may be directly joined to a middle portion of the side sill  5 . In particular, the lower connection portion  13  may include a lower front wall  31  extending from the front wall  21  of the center pillar  11 , a lower rear wall  32  extending from the rear wall  22  of the center pillar  11 , and a lower outboard side wall  35  extending from the outboard side wall  25  of the center pillar  11 . The lower front wall  31  may be provided on a front edge of the lower outboard side wall  35 , and the lower rear wall  32  may be provided on a rear edge of the lower outboard side wall  35 . A lower front flange  33  may extend from the lower front wall  31  toward the front of the vehicle, and a lower rear flange  34  may extend from the lower rear wall  32  toward the rear of the vehicle. 
     The pair of side sills  5  may be disposed on both side edges of the vehicle. Each side sill  5  may extend along a corresponding edge of the vehicle. The side sill  5  may include a side sill outer facing the exterior of the vehicle and a side sill inner facing the interior of the vehicle. The side sill  5  illustrated in  FIGS.  1 ,  2 ,  4 ,  5 , and  6    may be referred to as the side sill outer, and the side sill inner may be omitted. 
     Referring to  FIGS.  1 ,  3 ,  5 , and  6   , a pillar reinforcement  15  may be joined to an inboard surface of the center pillar  11 . 
     Referring to  FIG.  3   , the pillar reinforcement  15  may include a front wall  41  facing the front of the vehicle, a rear wall  42  facing the rear of the vehicle, and a side wall  45  located between the front wall  41  and the rear wall  42 . The front wall  41  may be provided on the front of the side wall  45 , and the rear wall  42  may be provided on the rear of the side wall  45 . 
     The front wall  41  of the pillar reinforcement  15  may have a shape matching the front wall  21  of the center pillar  11  and the lower front wall  31  of the lower connection portion  13 , and the front wall  41  of the pillar reinforcement  15  may be joined to the front wall  21  of the center pillar  11  and the lower front wall  31  of the lower connection portion  13  using fasteners, welding, and/or the like. 
     The rear wall  42  of the pillar reinforcement  15  may have a shape matching the rear wall  22  of the center pillar  11  and the lower rear wall  32  of the lower connection portion  13 , and the rear wall  42  of the pillar reinforcement  15  may be joined to the rear wall  22  of the center pillar  11  and the lower rear wall  32  of the lower connection portion  13  using fasteners, welding, and/or the like. 
     The side wall  45  of the pillar reinforcement  15  may have a shape matching the outboard side wall  25  of the center pillar  11  and the lower outboard side wall  35  of the lower connection portion  13 , and the side wall  45  of the pillar reinforcement  15  may be joined to the outboard side wall  25  of the center pillar  11  and the lower outboard side wall  35  of the lower connection portion  13  using fasteners, welding, and/or the like. Referring to  FIG.  6   , a closed cavity  65  may be defined between the side wall  45  of the pillar reinforcement  15  and the outboard side wall  25  of the center pillar  11 . Thus, stiffness of the center pillar  11  may be improved by the pillar reinforcement  15  and the closed cavity  65 . 
     The pillar reinforcement  15  may include a bottom flange  43  provided on a bottom end of the side wall  45 . The bottom flange  43  of the pillar reinforcement  15  may be joined to an intermediate connection portion  12  of the side sill  5  by spot welding and/or the like. 
     Referring to  FIG.  1   , the lower connection portion  13  of the center pillar  11  may be joined to the middle portion of the side sill  5  using fasteners, welding, and/or the like so that a joint portion may be formed between the lower connection portion  13  of the center pillar  11  and the middle portion of the side sill  5 . 
     The side sill  5  may include an outboard side wall facing the exterior of the vehicle, a top wall facing the top of the vehicle, and a bottom wall facing the bottom of the vehicle. Referring to  FIGS.  1 ,  2 , and  4   , the side sill  5  may have a top flange  6  and a bottom flange  7 . The side sill  5  may include the intermediate connection portion  12  provided in the middle portion thereof. The lower connection portion  13  of the center pillar  11  may be joined to the intermediate connection portion  12  of the side sill  5  using fasteners, welding, and/or the like. 
     The intermediate connection portion  12  may include an outboard side wall  61  facing the exterior of the vehicle, a top wall  62  facing the top of the vehicle, and a bottom wall  63  facing the bottom of the vehicle. The outboard side wall  61  of the intermediate connection portion  12  may be aligned with the outboard side wall of the side sill  5 , the top wall  62  of the intermediate connection portion  12  may be aligned with the top wall of the side sill  5 , and the bottom wall  63  of the intermediate connection portion  12  may be aligned with the bottom wall of the side sill  5 . 
     The intermediate connection portion  12  may have a pair of projections  12   a  provided on the top thereof, and a recess  12   b  located between the pair of projections  12   a.  The pair of projections  12   a  may have a shape corresponding to the lower front flange  33  and the lower rear flange  34  of the lower connection portion  13  of the center pillar  11 . According to an exemplary embodiment, the lower front flange  33  and the lower rear flange  34  of the lower connection portion  13  may be accurately joined to the intermediate connection portion  12  of the side sill  5  by spot welding and/or the like. 
     The bottom flange  43  of the pillar reinforcement  15  may be directly joined to the top wall  62  of the intermediate connection portion  12  of the side sill  5  using fasteners, welding, and/or the like. Accordingly, the front wall  41 , the rear wall  42 , and the side wall  45  of the pillar reinforcement  15  may be joined to the lower connection portion  13  of the center pillar  11 , and the bottom flange  43  of the pillar reinforcement  15  may be joined to the top wall  62  of the intermediate connection portion  12  of the side sill  5  so that the lower connection portion  13  of the center pillar  11  may be more firmly connected to the intermediate connection portion  12  of the side sill  5  through the pillar reinforcement  15 . That is, the pillar reinforcement  15  may increase connection stiffness between the lower connection portion  13  of the center pillar  11  and the intermediate connection portion  12  of the side sill  5  through the bottom flange  43 . 
     Referring to  FIGS.  4  to  6   , a side sill reinforcement  14  may be joined to an inboard surface of the intermediate connection portion  12  of the side sill  5 . The intermediate connection portion  12  of the side sill  5  may increase its own stiffness with the side sill reinforcement  14 . 
     Referring to  FIGS.  2  and  4   , the side sill reinforcement  14  may include a side wall  51  joined to the outboard side wall  61  of the intermediate connection portion  12 , and a top wall  52  joined to the top wall  62  of the intermediate connection portion  12 . Accordingly, the side sill reinforcement  14  may have an L-shaped cross section. 
     Referring to  FIGS.  1  and  4  to  6   , a plurality of bulkheads  16  may be joined to the inboard surface of the intermediate connection portion  12  of the side sill  5  and the side sill reinforcement  14 . Referring to  FIG.  2   , each bulkhead  16  may have a pair of mounting flanges  66 . Each mounting flange  66  may have a shape corresponding to the outboard side wall  61 , the top wall  62 , and the bottom wall  63  of the intermediate connection portion  12 , and the mounting flanges  66  of each bulkhead  16  may be joined to the inboard surface of the intermediate connection portion  12  using fasteners, welding, and/or the like. In particular, at least a portion of the mounting flanges  66  of the bulkhead  16  may be joined to the side wall  51  and the top wall  52  of the side sill reinforcement  14  using fasteners, welding, and/or the like. Accordingly, the side sill reinforcement  14  may connect the plurality of bulkheads  16  in a longitudinal direction of the side sill  5 , and the intermediate connection portion  12  of the side sill  5  may increase its own stiffness and strength with the plurality of bulkheads  16  and the side sill reinforcement  14 . 
     Referring to  FIG.  6   , the lower outboard side wall  35  of the lower connection portion  13  of the center pillar  11  may be joined to an outboard surface of the outboard side wall  61  of the intermediate connection portion  12  of the side sill  5  by a plurality of spot welds W 1 . Since a joint area between the lower outboard side wall  35  of the lower connection portion  13  and the outboard side wall  61  of the intermediate connection portion  12  is relatively large, the lower connection portion  13  of the center pillar  11  may be firmly joined to the intermediate connection portion  12  of the side sill  5 . The side wall  51  of the side sill reinforcement  14  may be joined to an inboard surface of the outboard side wall  61  of the intermediate connection portion  12  of the side sill  5  by a plurality of spot welds W 2 . Accordingly, the lower outboard side wall  35  of the lower connection portion  13  and the side wall  51  of the side sill reinforcement  14  may partially overlap each other with the outboard side wall  61  of the intermediate connection portion  12  interposed therebetween so that the outboard side wall  61  of the intermediate connection portion  12  may be sandwiched between the lower outboard side wall  35  of the lower connection portion  13  and the side wall  51  of the side sill reinforcement  14 . Thus, the lower connection portion  13  of the center pillar  11  and the side wall  51  of the side sill reinforcement  14  may be firmly supported with respect to the outboard side wall  61  of the intermediate connection portion  12  of the side sill  5  so that the connection stiffness between the lower connection portion  13  of the center pillar  11  and the intermediate connection portion  12  of the side sill  5  may be improved. 
     Referring to  FIG.  6   , the top wall  52  of the side sill reinforcement  14  may be joined to an inboard surface of the top wall  62  of the intermediate connection portion  12  of the side sill  5  by a plurality of spot welds W 3 . The bottom flange  43  of the pillar reinforcement  15  may be joined to an outboard surface of the top wall  62  of the intermediate connection portion  12  of the side sill  5  by a plurality of spot welds W 4 . Accordingly, the bottom flange  43  of the pillar reinforcement  15  and the top wall  52  of the side sill reinforcement  14  may overlap (face) each other with the top wall  62  of the intermediate connection portion  12  interposed therebetween so that a portion of the top wall  62  of the intermediate connection portion  12  may be sandwiched between the bottom flange  43  of the pillar reinforcement  15  and the top wall  52  of the side sill reinforcement  14 . Thus, the bottom flange  43  of the pillar reinforcement  15  and the top wall  52  of the side sill reinforcement  14  may be firmly supported with respect to the top wall  62  of the intermediate connection portion  12  so that the connection stiffness between the bottom flange  43  of the pillar reinforcement  15  and the top wall  62  of the intermediate connection portion  12  of the side sill  5  may be improved. 
     Referring to  FIG.  6   , in a joint portion between the lower connection portion  13  of the center pillar  11  and the intermediate connection portion  12  of the side sill  5 , the bottom flange  43  of the pillar reinforcement  15  may be joined to the outboard surface of the top wall  62  of the intermediate connection portion  12  of the side sill  5 , and the top wall  52  of the side sill reinforcement  14  may be joined to the inboard surface of the top wall  62  of the intermediate connection portion  12  of the side sill  5  so that the lower connection portion  13  of the center pillar  11  and the intermediate connection portion  12  of the side sill  5  may be connected to form a T-shaped structure. Thus, joint stiffness between the lower connection portion  13  of the center pillar  11  and the intermediate connection portion  12  of the side sill  5  may be improved. 
     As set forth above, according to exemplary embodiments of the present disclosure, by increasing stiffness and strength with respect to the joint portion between the lower portion of the center pillar and the side sill, side crash performance (crashworthiness) of the vehicle may be improved. Specifically, in the joint portion between the lower connection portion of the center pillar and the intermediate connection portion of the side sill, the bottom flange of the pillar reinforcement and the outboard surface of the top wall of the intermediate connection portion of the side sill may be joined, and the top wall of the side sill reinforcement and the inboard surface of the top wall of the intermediate connection portion of the side sill may be joined so that the lower connection portion of the center pillar and the intermediate connection portion of the side sill may be joined to form a T-shaped structure, thereby improving the joint stiffness between the lower connection portion of the center pillar and the intermediate connection portion of the side sill. 
     Hereinabove, although the present disclosure has been described with reference to exemplary embodiments and the accompanying drawings, the present disclosure is not limited thereto, but may be variously modified and altered by those skilled in the art to which the present disclosure pertains without departing from the spirit and scope of the present disclosure claimed in the following claims.