Patent ID: 8864198

Claim:
A tubular back beam for a vehicle, comprising: an upper beam and a lower beam spaced apart from each other in a vertical direction, each beam having a tubular structure; a plurality of connecting lugs disposed along a longitudinal direction between the upper and lower beams and interconnecting the upper and lower beams; a center bracket interconnecting central portions of the upper and lower beams in the longitudinal direction thereof to each other; a pair of side brackets interconnecting opposite ends of the upper and lower beams to each other; and a pair of crash boxes coupled to the opposite ends of the upper and lower beams, wherein each respective crash box has one end facing a corresponding side bracket and an other end coupled to a side member such that ends of the upper and lower beams are disposed between the respective crash box and the corresponding side bracket; wherein each of the connecting lugs includes a U-shaped cross-section that is open in a direction towards a side of the beams where the side member is located, and is welded at opposite ends thereof to the upper and lower beams; wherein each of the upper and lower beams include a rectangular cross-section to ensure rigidity; wherein a maximum spacing distance between the upper and lower beams is about 100 mm to 110 mm; and wherein a pitch interval between the connecting lugs is about 1.8 to 2.2 times as long as the maximum spacing distance between the upper and lower beams.