초록 ▼

An improved cold formed, sheet metal profiled building unit and method of making the same are disclosed. The building unit incorporates at least one longitudinal stiffening rib in a longitudinal flat region of the type having a tendency to buckle when subjected to compressive forces. The longitudina

An improved cold formed, sheet metal profiled building unit and method of making the same are disclosed. The building unit incorporates at least one longitudinal stiffening rib in a longitudinal flat region of the type having a tendency to buckle when subjected to compressive forces. The longitudinal stiffening rib is formed not by drawing-in sheet metal as in current roll forming practices, but, instead, by stretching a segment of the sheet metal. Each longitudinal rib has a profile width, as measured along the centerline of the rib, which is greater than the linear of the sheet metal segment from which it was stretched-in. Roll forming machines incorporating the principles of this invention utilize fewer roll stands than do roll forming machines incorporating the principles of current roll forming practices.

대표청구항 ▼

In a profiled building unit formed from sheet metal having a substantially uniform sheet thickness and presenting alternating crests and valleys, and sloped webs connecting adjacent ones of said crests and said valleys, the improvement comprising: first and second stiffening ribs formed, respectivel

In a profiled building unit formed from sheet metal having a substantially uniform sheet thickness and presenting alternating crests and valleys, and sloped webs connecting adjacent ones of said crests and said valleys, the improvement comprising: first and second stiffening ribs formed, respectively, in said crests and said valleys, said stiffening ribs extending longitudinally along substantially the entire length of said building unit and each having a substantially uniform rib thickness that is less than said uniform sheet thickness of said metal sheet.