(57) Draw tape equipment (14), and methods for incorporating draw tapes (52, 54) into
plastic and like bags. A continuous plastic web (10) is slit at a slitting station
(16) to form layers (18, 20), and respective free edges (22, 24). The web (10) then
passes to a hole forming station (26) where holes (28) are formed in the top and bottom
layers adjacent the free edges. After the holes (28) are punched, edge regions (34,
36) of the top and bottom layers (18, 20) are separated from each other, followed
by the forming of hems (40, 42) in the separated layers at hem forming stations (44,
46) arranged in parallel with each other. Concurrent with forming of the hems (40,
42), continuous draw tapes (52, 54) are fed to the hem forming stations (44, 46) and
the hems are formed about the draw tapes. The formed hems, (40, 42) with the draw
tapes incorporated therein, optionally pass through transverse stretching apparatus
(152) and/or through electrostatic pinning apparatus (154) and/or through first temperature
control stations (60) where the temperature of the plastic web (10) is controlled
to a desired temperature before hem sealing. The formed hems are then sealed to the
main bodies of the respective top and bottom layers. The sealed hems (40, 42) optionally
pass through second temperature control stations (76) to cool the web. The edge regions
(34, 36) of the layers (18, 20) are then rejoined, in face-to-face relationship with
each other.
|
|
