Patent ID: 8857894

Claim:
A chassis frame side rail of a vehicle, said side rail comprising two opposing section pieces, each section piece having a U-shaped cross section, and a pair of opposing welding longitudinal connecting tabs that extend ends of a pair of opposing branches of the respective section piece substantially perpendicularly, the connecting tabs of the opposing section pieces welded together to attach the section pieces together, wherein each section piece further comprises: a joining area formed between each one of the longitudinal connecting tabs and a respective one of the branches of the respective section piece that the respective connecting tab extends from, each joining area providing two separate longitudinal plastic hinges upon a longitudinal compressive impact to the side rail such that the side rail deforms in an accordion like manner so as to keep the attachment by welding of the longitudinal connecting tabs intact, wherein each joining area comprises a curve having a radius greater than or equal to 12 mm formed between the respective longitudinal connecting tab and the respective branch of the respective section piece.