| 摘要 |
A method, and an apparatus for carrying out that method, for making roofing from a stretchable and deformable sheet material. The roofing sections are made from sheet material which has a preformed laterally sinu-soidal configuration which is reconfigured with longitudinally spaced steps (or folds). The finished sheet is a roofing section having the configuration of stepped tile roofing which is a substitute for true roofing tile. The sinu-soidal sheet is clamped (or pressed) in a tool between two adjacent pairs of complimentary shape clamping jaws. In that tool apparatus the two pairs of clamps are then moved relative to each in parallel paths normal to longitudinal and lateral planes through the sheet, which movement stretches the sheet to form a step (or fold) between the portions held in the two sets of clamps. More than two sets of pairs of tools can be used to simultaneously form multiple steps and alternatively the sinu-soidal sheet can be periodically shifted and step stretched in a continuous operation. |
