| 摘要 |
An elongate panel of a flexible sheet material which is not heat-sealable is formed into a succession of bags by advancing the panel in the direction of its length between a rectangular shaping tube and a folding box to form the panel into a tubular structure of rectangular cross section, applying a bead of adhesive material along one longitudinal edge of the panel and bringing the other longitudinal edge thereof against the adhesive to form a longitudinal seam, applying a bead of adhesive material to one narrow side and both wide sides of the tubular structure in the region defining the bottom of each bag to cause this bead to have the form of a U in a plane lying perpendicular to the length of the tubular structure, severing the tubular structure just downstream of each U-shaped bead, and forming the bottom of each bag by first folding in successive narrow sides of the tubular structure adjacent the associated line of severance, to give the wide sides the form of triangular ears each composed of two layers of sheet material, and then folding successive ears in against the folded narrow sides, the folded narrow sides being joined together, the layers of each ear being joined together, and the ears being joined to one another and to the folded narrow sides by respective portions of the U-shaped adhesive bead.
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