| 摘要 |
1,238,810. Laminates. SWISS ALUMINIUM Ltd. 22 Jan., 1970 [23 Jan., 1969], No. 3205/70. Heading B5N. A method of bending a laminate of a layer 1 of a thermoplastic resin e.g. of polyethylene or polypropylene, with a metal cover sheet 2 e.g. of aluminium or an alloy thereof, on each side thereof comprises removing a strip 3 of the cover sheet 2 on the inner side of the corner to be formed and symmetrical about the bending line, the width of this strip being such that after the bending the free edges of the sheet left by its removal abut, pressing a heated blade into the resin along the bending line to form a groove U-shaped in cross-section with consequent displacement of some of the resin and to heat the resin and bending the laminate, the heated walls of the groove being brought into contact to weld together while the free metal edges abut against one another and shear away the displaced resin. In a preferred method, the corner formed is reinforced by sticking an angle strip of aluminium or aluminium alloy along the inner side of the bend by the interposition of a layer of adhesive or an adhesive foil. |
