Usg Interiors, Inc.

Donn Incorporated

Patrick M Kelly

Dennis A Alvarez

Gale E Sauer

Joseph A Hocevar

George F Bosl

Paul A Pomeroy

Robert E Howlett

A cold-forming method is disclosed for thinning localized, longitudinally extending portions of sheet metal by lateral shear deformation without any substantial longitudinal deformation. With such method, it is possible to produce elongated members which are thinned in zones of low stress and are thicker in zones of higher stress so as to provide high metal use efficiency. The method is performed by an apparatus including a rotating mandrel providing opposed conical surfaces and pressure rolls operable to apply forces substantially perpendicular to the axis of rotation of the mandrel to cause a portion of the sheet metal to yield in shear to reduce the thickness of longitudinally extending portions of the sheet metal. The forces are applied in a plane normal to the length of the strip in order to avoid longitudinal elongation.

Apparatus for producing cold roll-formed structures

Cold roll-formed structures and method and apparatus for producing same

A drywall corner bead providing a rounded nose and two mounting flanges extending from opposite sides of the nose is formed from a strip of galvanized metal of uniform thickness. The two flanges are provided with three discrete longitudinally extending bands of reduced thickness formed by shear deformation of the material forming the band. The flanges are knurled to emboss the surface thereof and openings are formed in the flanges at intervals along their length. The corner bead is formed by a method in which shear deforming forces are progressively applied to the material forming the thinned bands to produce lateral deformation of such material without any appreciable lengthwise deformation. After the thinned bands are formed, forces are applied to straighten the corner bead. Subsequently, the flanges are knurled to provide an embossed surface and holes are punched in the flanges at intervals along their length. Thereafter, the nose is formed to its final shape and the flanges are positioned at substantially right angles relative to each other.

Corner bead structure

Method for producing cold roll-formed structures

Growing community of inventors

Cleveland, OH, United States of America

Patrick M Kelly