Method of roll-forming an automotive bumper
AssigneeShape Corp.
InventorsPeter Sturrus, Richard Heinz
Life of this patent
Estimating the term…
Abstract
A bumper bar for vehicles formed from rolled sheet steel having a closed tubular profile designed to have a high impact resistance, high strength-to-weight ratio, and a low cost of manufacture. The bar is preferably swept along its longitudinal axis to create a curvature consistent with modern automotive designs.
Claims11
A method for forming a bumper bar for a vehicle comprising the steps of continuously roll-forming a sheet of high tensile strength steel having side edges to cause said side edges to abut one another;
- welding said side edges together to form an integral tube;
- providing a sweep forming means having curvilinear external mandrel means and curvilinear internal mandrel means spaced from each other to provide a passageway therebetween for receiving said integral tube therebetween;
- passing said integral tube through said passageway while said roll-forming step upstream of said external and internal mandrel means takes place and said upstream sheet connected to the integral tube is being roll-formed, and during said passing step continuously supporting the external and internal mandrel means in stationary positions, the internal means being supported by support means having an elongated member extending from said internal mandrel means to a support member, said support member being located upstream of said sweep forming means where the side edges of said strip are not abutting thereby providing an opening through which said support member extends for attachment to said elongated member;
- said step of passing said tube through said passageway producing a predetermined sweep in said tube as determined by the shape of said passageway;
- and
- cutting said swept integral tube at predetermined lengths after the sweeping of the tube has been completed to continuously form in succession a series of bumper bars during the roll-forming of said sheet upstream of said sweep forming means.
The method of claim wherein said bar is given a sweep of greater than #30 sweep.
A method of forming a bumper bar for a vehicle comprising the steps of providing a first roller means adapted to form a tube with an irregular surface;
- providing a sheet of high tensile strength steel having side edges and continuously passing said sheet through said first roller means to cause a tube to be formed with side edges abutting one another;
- welding said edges together to form an integral tube;
- providing a sweep forming means for forming a sweep in said tube;
- and
- providing a second roller means upstream of said sweep forming means, said second roller means shaped to extend into and engage at least portions of said irregular surfaces in the tube formed by said second roller means, causing said second roller means to engage said irregular surface of said tube;
- and
- driving said second roller means to cause said tube to be forced through said sweep forming means thereby forming a sweep in said integral tube.
Dependencies are inferred from the claim text.