IMPROVED METHOD OF EXTENSION OF EXTENSIBLE ZERO-DEFORMATION LAMINATED CANVAS AND DEVICE FOR ITS REALIZATION Russian patent published in 1997 - IPC

FIELD: method of extension and device for extension of laminated zero-deformation canvas assembled in an essentially non-extended state, which becomes elastic as a result of mechanical extension. SUBSTANCE: after initial step extension parts of laminated zero-deformation canvas are subjected to further step extension. This extension is accomplished by engagement of the processed surface of initially extended canvas with the second pair of opposite devices of pressure application. These devices have three-dimensional surfaces, which completely or partially supplement one another and are engaged to a higher degree than the first pair of opposite devices of pressure application. Due to it, the second extensible layer still more extends with a minimum damage of successive extension by these operations. The laminated canvas acquires an ability for elastic extension in the direction of step extension at least to the point of extension by the second pair of opposite devices of pressure application after ceasing of action of step extension forces on laminated canvas. Extensible zero-deformation laminated canvas between the first and second pairs of opposite devices of pressure application is fed continuously. Use is made of opposite devices of pressure application in the form of channeled rolls with axes of rotation perpendicular to the direction of canvas motion and with three-dimensional surfaces having lugs which completely or partially supplement one another. The lugs of the channeled rolls of the second pair of opposite devices of pressure application are engaged with one another to a higher degree than the lugs of the channeled rolls of the first pair. In the improved device for extension of extensible laminated zero-deformation canvas the means for step extension of parts of extensible laminated zero-deformation canvas are furnished with the second pair of opposite devices of pressure application. This pair of devices has three- dimensional surfaces supplementing one another and engaged to a higher degree than the first pair of opposite devices of pressure application for further step extension of the initially extended parts of laminated canvas. EFFECT: facilitated procedure. 10 cl, 10 dwg