Patent ID: 6408893
Filing Date: 2002-06-25
Classification: D03D

Abstract:
A method of manufacturing a specialty tubular bag wherein the tubular bag wall has at least one venting band extending along a length of a corresponding tubular sheet, said method comprising the steps of:weaving a tubular sheet of flexible material with a circular loom to form an elongated tube comprising woven warp and weft strands, with said tubular sheet having a longitudinal axis parallel to said warp strands and a transverse axis parallel to said weft strands; adapting, during said weaving step with said circular loom, at least one expansion block disposed with an associated means of fixturing said expansion block around a periphery of a concentration ring of said circular loom whereby said expansion block is used to replace a corresponding group of otherwise normally supplied warp strands to be woven; creating, along the periphery of the woven tubular sheet, a set of said venting bands each corresponding to the location of an expansion block, where each venting band runs parallel to said longitudinal axis, said weft strands and said warp strands surrounding the said expansion block; sectioning off said tubular sheet along a set of lines perpendicular to said longitudinal axis and with a predetermined spacing to form a set of tubular segments, whereby each said tubular segments comprising said set of venting bands extending longitudinally from a first open end to a second open end with the first open end of said tubular sheet named the top opening and the second open end of said tubular sheet named the bottom opening; and sewing said bottom opening of said tubular sheet closed along a direction perpendicular to the said longitudinal axis with said top opening of said tubular sheet left open forming a desired bag opening.