MONOTONOUS FABRIC OF FILAMENTS DRAWN FROM MELT, METHODS AND APPARATUSES FOR MANUFACTURING THE SAME Russian patent published in 2003 - IPC

FIELD: textile industry. SUBSTANCE: apparatus has collector with substantially cylindrical forming surface, source capable of directing filaments drawn from melt onto forming surface, said forming surface being mounted for rotation about longitudinal axis and simultaneously for displacement in parallel with said longitudinal axis, so point defined on forming surface may move in helical spiral path from one end of collector to other end. Said helicoid spiral path is defined by helicoid spiral angle with respect to longitudinal axis. Apparatus is further equipped with separator for separating nonwoven sleeve made on forming surface in direction substantially corresponding to helicoid spiral angle so as to transform sleeve into flat sliver. Method involves using collector with substantially cylindrical forming surface adapted for rotation about longitudinal axis and simultaneously for displacement in parallel with longitudinal axis so that any selected point on forming surface is movable in helicoid spiral path around and along collector, from one end thereof to other end, said helicoid spiral path defining helicoid spiral angle with respect to longitudinal axis; directing filaments drawn from melt onto forming surface for forming sleeve; separating sleeve in direction substantially corresponding to helicoid spiral angle for transforming said sleeve into flat sliver. Methods for manufacture of filters and masks are described. First method involves placing electrically charged fabric manufactured by above method into supporting structure. Second method involves placing said fabric into supporting structure made in the form of bowl. Multilayer fabric comprises plurality of mutually connected layers composed of filaments drawn from melt. At least one layer has one untied edge and two separated edges. Untied edge is positioned between two separated edges, said edges being arranged in parallel with one another. Fabric is designed for manufacture of filters for masks or respirators. EFFECT: improved quality of fabric with stable weight and stable density of edges and reduced wastes. 17 cl, 16 dwg