Patent Publication Number: US-2023144305-A1

Title: Bumper beam for a motor vehicle

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application claims priority to Korean Patent Application No. 10-2021-0154689, filed Nov. 11, 2021, the entire contents of which is incorporated herein for all purposes by this reference. 
     BACKGROUND 
     Field 
     The present disclosure relates to a bumper beam for a motor vehicle. More particularly, the present disclosure relates to a bumper back beam free of mobility-specificity of which collision performance is secured and which may be altered according to design and specification needed in mobility, thereby satisfying various mobilities with minimum molds and allowing flexible applications. 
     Description of the Related Art 
     In general, a motor vehicle is provided with bumpers on the front and rear ends to absorb the impact of a collision or mitigate injuries inflicted upon a pedestrian in the event of a collision with the pedestrian. 
     The bumpers include bumper covers and bumper back beams. Specifically, the bumper covers are mounted at the frontmost and rearmost ends of the vehicle to form the front and rear exterior and to be the first to receive the impact applied from the outside in the event of a collision. The bumper covers have built-in buffer materials so that the impact applied from outside is more easily absorbed. 
     On the other hand, the bumper back beams are positioned behind the bumper covers to absorb the impact applied through the bumper covers. 
     Here, the bumper back beam made of a steel material has a problem of increased weight, while the bumper back beam made of a fiber-reinforced thermoplastic has low strength and rigidity. 
     In addition, the bumper back beam is installed in a crash box to obtain high energy absorption in the event of a collision. 
     However, in the case of the conventional bumper back beam, the bumper back beam and a crash box are integrated so that the bumper back beam is not replaceable. 
     That is, the bumper back beam is tailored to a specific vehicle so that the bumper back beam may not be flexibly applied to various vehicle types for replacement purposes. 
     The development of automotive technology has yet to meet the requirements of the bumper back beam according to various sizes and designs so that there still is a problem that every new automotive mobility needs a newly designed mold. 
     The matters described above as a technical background are intended only for a better understanding of the background of the present disclosure and are not to be taken as acknowledgment that they pertain to the conventional art already known to those skilled in the art. 
     SUMMARY 
     The present disclosure is proposed to resolve the issue described above, and an object of the present disclosure is to provide a bumper back beam of which collision performance is secured and which may be altered according to design and specification needed in mobility, thereby satisfying various mobilities with minimum molds and allowing flexible applications. 
     To achieve the object described above, the bumper back beam free of mobility-specificity includes a center portion provided with a coupling end part formed at either end, and a side portion positioned at either end of the center portion and provided with a connecting end part having a section overlapping the coupling end part, wherein the center portion and the side portion are coupled to each other through the coupling end part and the connecting end part which are the overlapping sections. 
     The center portion is made of a continuous fiber-reinforced thermoplastic and the side portion is made of a glass fiber mat plastic. 
     The coupling end part is formed such that a rear surface is recessed in a form matching the connecting end part so that the connecting end part of the side portion is seated in a recessed portion. 
     A plurality of recessed portions recessed rearward are formed in the vertical direction in the coupling end part. 
     A plurality of mounting portions in which the respective recessed portions are seated in a state where the connecting end part matches the coupling end part are formed in the connecting end part. 
     The recessed portion and mounting portion are fastened by the penetration of a fastening member so that the coupling end part and connecting end part are coupled to each other, and the recessed portion is recessed deep enough for a head part of the fastening member not to protrude forward in a state where the fastening member fastens. 
     A bush portion is interposed between the recessed portion and the mounting portion and a fastening member fastens through the bush portion so that the coupling end part and the connecting end part are coupled to each other. 
     The coupling end part and the connecting end part are formed such that the parts facing each other are in linear contact with each other with respect to the front. 
     The side portion is fixedly fastened to a crash box in a state where the side portion is coupled to the center portion. 
     A crash box connecting part to be connected to the crash box is formed and a center extending part is formed between the crash box connecting part and connecting end part in the side portion. 
     The length of the center extension part in the side portion is altered according to the overall width of the mobility. 
     The bumper back beam free of mobility-specificity structured as described above includes the center portion free of mobility-specificity and the side portion that may be altered according to the design and specification of mobility in order to secure collision performance so that the back beam of which collision performance is secured and which satisfies various mobilities may be flexibly applied. 
     Accordingly, it is possible to configure the back beam satisfying various mobilities based on a standardized model to secure collision performance so that manufacturing cost is reduced by assembling and producing the back beams with minimum molds. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a view of a bumper back beam free of mobility-specificity according to the present disclosure. 
         FIG.  2    is a top view of the bumper back beam free of mobility-specificity shown in  FIG.  1   . 
         FIG.  3    is a cross-sectional view of the bumper back beam free of mobility-specificity shown in  FIG.  1   . 
         FIG.  4    is a view for describing an application example of the bumper back beam free of mobility-specificity according to an embodiment of the present disclosure. 
         FIG.  5    is a view for describing an application example of the bumper back beam free of mobility-specificity according to another embodiment of the present disclosure. 
         FIG.  6    is a view for describing an application example of the bumper back beam free of mobility-specificity according to still another embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, a bumper back beam free of mobility-specificity according to a preferable embodiment of the present disclosure will be described with reference to the accompanying drawings. 
     As shown in  FIGS.  1  to  3   , the bumper back beam free of mobility-specificity according to the present disclosure includes a center portion  100  made of a continuous fiber-reinforced thermoplastic, a first side portion  200  positioned at a first end of the center portion  100 , and a second side portion  202  positioned at a second end of the center portion  100 . The first and second side portions  200 ,  202  are made of glass fiber mat plastic. 
     Here, the center portion  100  may be manufactured by shape-processing continuous fiber-reinforced thermoplastic including glass fiber or carbon fiber by a hot pressing method. 
     Since the center portion  100  is the first to receive the impact and deform in the event of a collision, the center portion  100  may be formed in a skeletal structure based on impact performance and be fixed in a shape optimized for collision performance to be equally applicable to all mobilities. Accordingly, the center portion  100  secures an impact height and collision performance of the geometric conditions. 
     The side portions  200 ,  202  may be manufactured by shape-processing, by a hot pressing method, glass fiber mat thermoplastic of which the degree of freedom in shaping may be maximized compared with the center portion  100 . 
     That is, the secured design freedom allows the side portions  200 ,  202  to be designed into various forms according to design and specification of the mobility while supporting the center portion  100 . 
     The present disclosure standardizes the center portion  100  of which the collision performance is secured and replaces the side portions  200 ,  202  according to the design and specification of the mobility in configuring the bumper back beam so that replacement of the side portions allows flexible application according to the design and specification of the mobility even when the width between the side members of the mobility changes. 
     In particular, the center portion  100  and the side portions  200 ,  202  have overlapping sections, and are coupled to each other over the overlapping sections. 
     The partial overlapping structure of the center portion  100  and each side portion  200 ,  202  ensures that the coupling rigidity between the center portion  100  and the side portion is secured. At this time, the overlapping structure of the center portion  100  and the side portions  200 ,  202  in the front-rear direction leads to an advantage in dispersing the impact in the event of a collision and securing the collision rigidity. 
     In addition, the center portion  100  and the side portions  200 ,  202  are overlapped with each other such that the center portion  100  is disposed in front of the side portions so that the center portion  100  to which impact is first applied in the event of a collision attenuates the impact through deformation. 
     In this way, the present disclosure secures the fastening strength and collision rigidity through the connecting structure between the center portion  100  and the side portions  200 ,  202 . 
     To be specific about the present disclosure described above, as shown in  FIGS.  2  and  3   , coupling end parts  110 ,  112  are formed at either end of the center portion  100 , and the side portions  200 ,  202  extend to the rear of the coupling end parts  110 ,  112  in a state where the side portions  200 ,  202  are disposed at either end of the center portion  100 , such that the connecting end parts  210 ,  212  each have a section overlapping the coupling end parts  110 ,  112  are formed. 
     The coupling end parts  110 ,  112  are formed at either end of the center portion  100 , the side portions  200 ,  202  are respectively disposed at either end of the center portion  100 , and the connecting end parts  210 ,  212  overlap and are connected to the coupling end parts  110 ,  112 . 
     This configuration enhances coupling rigidity, and the collision rigidity is secured by the advantage in dispersing the impact. Here, in the section where the coupling end parts  110 ,  112  and the connecting end parts  210 ,  212  overlap with each other, the length of the overlapping section is to be 50 mm or more and the thickness is to be 10 mm or more in order to secure robust coupling performance. 
     In addition, each connecting end part  210 ,  212  extends to the rear of the each coupling end part  110 ,  112  so that the center portion  100  may first deform by the collision to absorb the impact and the impact may be dispersed as the side portions  200 ,  202  stably support the center portion  100 . 
     On the other hand, as shown in  FIG.  2   , the coupling end parts  110 ,  112  are formed such that a rear surface is recessed in a form matching the connecting end parts  210 ,  212  so that the connecting end part of each side portion  200 ,  202  is seated in a recessed portion. 
     In this way, the connecting end part  210  of the side portion  200  overlaps, and is coupled to, the coupling end part  110  of the center portion  100  from the rear, and the coupling end part  110  is formed such that the rear surface is recessed in a form matching the connecting end part  210  so that the connecting end part  210  is seated in the coupling end part  110 . 
     This allows regulation of the coupling position of the coupling end parts  110 ,  112  and the connecting end parts  210 ,  212  by seating each connecting end part  210 ,  212  in the respective coupling end part  110 ,  112  at the time of coupling with each other. 
     In addition, since each connecting end part  210 ,  212  is seated in the respective coupling end part  110 ,  112 , the coupling rigidity between each coupling end part and each connecting end part increases. 
     On the other hand, as shown in  FIG.  3   , a plurality of recessed portions  120  recessed rearward are formed in the vertical direction in the coupling end part  110  and mounting portions  220 , on the front surfaces of which the respective recessed portions  120  are seated in a state where the connecting end parts  210 ,  212  match the coupling end parts  110 ,  112 , are formed in the connecting end parts. 
     The present disclosure illustrates the center portion  100  and the side portions  200 ,  202  in a ‘C’ shape, but various shapes may be applied to the center portion  100  and the side portions depending on the layout that considers the bumper back beam rigidity, design, and the like. 
     Here, recessed portions  120 ,  122  recessed from the front to the rear are formed in the coupling end parts  110 ,  112  of the center portion  100 , and mounting portion  220 ,  222  is formed in the connecting end parts  210 ,  212  such that the mounting portions may match the recessed portions  120 ,  122 . The recessed portions  120 ,  122  may be inserted into the mounting portions  220 ,  222  so that the recessed portions are inserted into the mounting portions  220 ,  222  when the coupling end parts  110 ,  112  and the connecting end parts  210 ,  212  are matched. 
     This allows the coupling end parts  110 ,  112  and the connecting end parts  210 ,  212  to be in a temporarily fixed state by the recessed portions  120 ,  122  and the mounting portions  220 ,  222  so that coupling through the fastening of fastening members  300 ,  302  is made easy. The fastening member  300  may be a bolt. 
     The recessed portions  120 ,  122  and the mounting portions  220 ,  222  are parts that the fastening members  300 ,  302  fastens, and the number of formations may be determined according to the coupling rigidity between the center portion  100  and the side portions  200 ,  202 . 
     The recessed portions  120 ,  122  and the mounting portions  220 ,  222  may be fastened by the penetration of the fastening members  300 ,  302  so that the coupling end parts  110 ,  112  and the connecting end parts  210 ,  212  may be coupled to each other, and the recessed portions  120 ,  122  may be recessed deep enough for the head parts  310 ,  312  of the fastening members  300 ,  302  not to protrude forward in a state where fastening members  300 ,  302  fasten. 
     That is, the recessed portions  120 ,  122  are recessed deeper than the head parts  310 ,  312  of the fastening members  300 ,  302  so that the head parts do not protrude forward of the center portion  100  when the recessed portions  120 ,  122  and the mounting portions  220 ,  222  are fastened by the penetration of the fastening members  300 ,  302 . This allows the fastening members  300 ,  302  to avoid the firsthand impact in the event of a collision so that separation between the center portion  100  and the side portions  200 ,  202  caused by the damage to the fastening member is prevented. 
     On the other hand, bush portions  400 ,  402  are interposed between the recessed portions  120 ,  122  and the mounting portions  220 ,  222 , and the fastening members  300 ,  302  fastens through the bush portions  400 ,  402  so that the coupling end parts  110 ,  112  and the connecting end parts  210 ,  212  may be coupled to each other. 
     As shown in  FIG.  3   , each bush portion  400 ,  402  may be mounted in a recessed portion  120 ,  122  or a mounting portion  220 ,  222 , and each bush portion  400 ,  402  is interposed between, and firmly fixes, the recessed portion  120 ,  122  and the mounting portion  220 ,  222  when the coupling end part  110 ,  112  and the connecting end part  210 ,  212  are coupled to each other. In addition, the fastening members  300 ,  302  are screwed into the bush portions  400 ,  402  to be firmly mounted through the bush portions so that the coupling end parts  110 ,  112  and the connecting end parts  210 ,  212  may be firmly coupled to each other through the fastening members  300 ,  302 . 
     On the other hand, as shown in  FIG.  2   , the coupling end parts  110 ,  112  and the connecting end parts  210 ,  212  are formed such that the parts facing each other are in linear contact with each other with respect to the front. 
     The coupling end parts  110 ,  112  and the connecting end parts  210 ,  212  are matched in the longitudinal direction and the facing parts are matched on a straight line. This improves the convenience of assembling the coupling end parts  110 ,  112  and the connecting end parts  210 ,  212  when coupled to each other. 
     In addition, the center portion  100  receives the impact first in the event of a collision, and the collision performance is secured by the deformation of the center portion  100  and the transfer of the impact to the side portions  200 ,  202 . 
     On the other hand, the side portions  200 ,  202  are each fixedly fastened to a crash box  500 ,  502  in a state where the side portions  200 ,  202  are coupled to the center portion  100  so that the bumper back beam according to the present disclosure may be mounted in the mobility. The side portions  200 ,  202  and the crash boxes  500 ,  502  may be bolted together, for example. 
     In this way, the present disclosure standardizes the center portion  100  of which the collision performance is secured and replaces the side portions  200 ,  202  according to the design and specification of the mobility in configuring the bumper back beam so that replacement of the side portions  200 ,  202  allow flexible application according to the design and specification of the mobility even when the width between the side members of the mobility changes. 
     That is, crash box connecting parts  230 ,  232  to be connected to the crash boxes  500 ,  502  are formed, and center extending parts  240 ,  242  are formed between the crash box connecting parts  230 ,  232  and the connecting end parts  210 ,  212  in the side portions  200 ,  202 . This allows the side portions  200 ,  202  to be bolted to the crash boxes  500 ,  502  through the crash box connecting parts  230 ,  232 . Vertical extension of the crash box connecting pas  230 ,  232  toward the crash box  500 ,  502  secures support rigidity between the side portions  200 ,  202  and the crash boxes  500 ,  502 . 
     In particular, the length of the center extending parts  240 ,  242  of the side portions  200 ,  202  is altered according to the full length of the mobility so that the side portions  200 ,  202  may be applied to various mobilities by adjusting the length of the center extending parts  240 ,  242  only while maintaining the shapes of the parts to be connected to the center portion  100  and the crash boxes  500 ,  502 . 
     That is, a comparison between  FIGS.  4  and  5    shows that, even when the distance differs between the side members, the same center portion  100  is used and only the side portions  200 ,  202  is replaced so that the distance difference between the side members may be dealt with by changing the length of the side portions  200 ,  202 . 
     In addition, a comparison between  FIGS.  4  and  6    shows that, even when the length differs between the crash boxes  500 ,  502 , the same center portion  100  is used and only the side portion  200  is replaced so that the length difference between the crash boxes  500 ,  502  may be dealt with. 
     The bumper back beam free of mobility-specificity having the structure as described above includes the center portion  100  flee of mobility-specificity and the side portions  200 ,  202  that may be altered according to design and specification of mobility in order to secure collision performance so that the back beam of which collision performance is secured and which satisfies various mobilities may be flexibly applied. 
     Accordingly, it is possible to configure the back beam satisfying various mobilities based on a standardized model to secure collision performance so that manufacturing cost is reduced by assembling and producing the back beams with minimum molds. 
     The specific embodiments of the present disclosure are illustrated and described, but it will be self-evident to those skilled in the art that the present disclosure may be improved upon and modified in various ways within the scope not departing from the technical spirit of the present disclosure provided by the patent claims below.