US 7,441,819 B2 · Tubular structural joint for automotive front end

Abstract

A structural joint is formed between the upper frame rail, which bends downwardly to define a generally vertically extending portion, and a generally fore-and-aft extending lower frame rail that can be tuned to manage the flow of crash energy during an impact situation. The upper frame rail is formed as a conventional four-sided tube, but is reformed at the intersection with the lower frame rail into a multiple-sided configuration that defines a mating surface for connection to the lower frame rail. The size of the mating surface has a fore-and-aft width dimension of between 20 and 40 millimeters and can be tuned to selectively control the management of crash forces encountered during an impact. The welded connection between the upper and lower frame rails forming this structural joint provides adequate stiffness and rigidity for the function of an automotive frame, yet presents a reduced shear strength in the fore-and-aft direction.

Claims19

Dependent claims

A structural joint in an automotive frame, comprising:

a first frame tubular member having a vertically extending portion;
a second frame member having a longitudinally extending portion located adjacent to the vertically extending portion of the first frame member;
the first frame member being configured into a multiple sided cross-sectional shape that defines a mating surface for welding to the second frame member and multiple non-mating surfaces, the mating surface having a longitudinally extending width dimension of between 20 and 40 millimeters, at least two of the non-mating surfaces having a width dimension corresponding to the longitudinally extending width dimension that is larger than the longitudinally extending width dimension of the mating surface to provide a breakaway connection in a longitudinal direction between said first and second frame member so that said structural joint is tuned to direct crash forces in a predetermined manner.

In an automotive frame having a tubular upper frame rail including a horizontally extending portion, a vertically extending portion and a bend portion interconnecting the horizontally and vertically extending portions;

a longitudinally extending lower frame rail spaced vertically below the upper frame rail, the vertically extending portion of the upper frame rail being located adjacent to the lower frame rail, an improved structural joint between the vertically extending upper frame rail and the lower frame rail comprising:
the horizontally extending portion being formed into a first cross-sectional configuration, the vertically extending portion of the upper frame rail being formed into a second cross-sectional configuration different from the first cross-sectional configuration that defines a mating surface for engagement with the lower frame rail, the mating surface having a longitudinally extending width dimension in the range of 20 to 40 millimeters, the mating surface being welded to the lower frame rail by longitudinally spaced, vertically extending weld lines having a predetermined length to provide a breakaway connection in a longitudinal direction between said first and second frame member so that said structural joint is tuned to direct crash forces in a predetermined manner.

Dependencies are inferred from the claim text.

Tubular structural joint for automotive front end

Life of this patent

Tubular structural joint for automotive front end

Life of this patent

Abstract

Claims19