Crash box and bumper for a motor vehicle

Abstract

A crash box for placement between a bumper beam and a side rail of a motor vehicle includes a longitudinal profile made of two U-shaped shells having overlapping ends sized to realize a material doubling for increasing side stiffness and to suit the side stiffness to a load level. A flange plate is provided on a side-rail-proximal end of the longitudinal profile and has an opening for passage of the longitudinal profile. The side-rail-proximal end of the longitudinal profile is configured with a collar which is turned outwards. The collar rests against the flange plate and is joined with the flange plate. In the event of a collision, the longitudinal profile of the crash box is moved into the side rail as the longitudinal profile folds into the side rail starting from the flange plate, while the side-rail-proximal end of the longitudinal profile remains secured to the flange plate.

1 . A crash box for placement between a bumper beam and a side rail of a motor vehicle, said crash box comprising:
 a longitudinal profile made of two U-shaped shells having overlapping ends sized to realize a material doubling for increasing a side stiffness and to suit the side stiffness to a load level; and   a flange plate provided on a side-rail-proximal end of the longitudinal profile and having an opening for passage of the longitudinal profile, wherein the side-rail-proximal end of the longitudinal profile is configured with a collar which is turned outwards, said collar resting against and joined with the flange plate.   
   
   
       2 . The crash box of  claim 1 , wherein the shells are identical. 
   
   
       3 . The crash box of  claim 1 , wherein the collar is turned in a direction of the longitudinal profile. 
   
   
       4 . The crash box of  claim 1 , wherein the collar is configured to wrap around a circumference of the longitudinal profile in the form of a ring. 
   
   
       5 . The crash box of  claim 1 , wherein the collar is joined to a longitudinal-profile-distal side of the flange plate. 
   
   
       6 . The crash box of  claim 1 , wherein the collar is joined to a longitudinal-profile-proximal side of the flange plate. 
   
   
       7 . The crash box of  claim 1 , wherein the collar is formed of collar portions, with one of the collar portions formed in one piece with one of the shells, and with the other one of the collar portions formed in one piece with the other one of the shells. 
   
   
       8 . The crash box of  claim 1 , wherein the longitudinal profile has rounded corners. 
   
   
       9 . The crash box of  claim 1 , wherein the longitudinal profile has a bumper-beam-proximal end with a slanted end surface. 
   
   
       10 . The crash box of  claim 1 , wherein the shells are made of different material. 
   
   
       11 . The crash box of  claim 1 , wherein the shells and the flange plate are made of different material. 
   
   
       12 . The crash box of  claim 1 , wherein the longitudinal profile has a varying wall thickness. 
   
   
       13 . The crash box of  claim 1 , wherein the shells are made of different wall thickness. 
   
   
       14 . The crash box of  claim 1 , wherein the shells and the flange plate are made of different wall thickness. 
   
   
       15 . A bumper for a motor vehicle, comprising:
 a bumper beam extending transversely to side rails of a motor vehicle; and   a crash box arranged between the bumper beam and one of the side rails, said crash box including a longitudinal profile made of two U-shaped shells having overlapping ends sized to realize a material doubling for increasing a side stiffness and to suit the side stiffness to a load level, and a flange plate provided on a side-rail-proximal end of the longitudinal profile and having an opening for passage of the longitudinal profile, wherein the side-rail-proximal end of the longitudinal profile is configured with a collar which is turned outwards, said collar resting against and joined with the flange plate, wherein the longitudinal profile of the crash box is constructed for movement into the side rail.   
   
   
       16 . The bumper of  claim 15 , wherein the longitudinal profile is constructed for crumpling into the side rail starting from the flange plate, while the side-rail-proximal end of the longitudinal profile remains secured to the flange plate.